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HomeMy WebLinkAboutWPO201900061 VSMP - SWPPP WPO VSMP 2020-08-28 GEORGETOWN HYDRAULIC STORMWATER POLLUTION PREVENTION PLAN And POLLUTION PREVENTION PLAN ALBEMARLE COUNTY July 30,2020 Project Name: GEORGETOWN HYDRAULIC Developer: BCM Holdings Group, LLC Reid Murphy 400 Locust Ave, Suite 3 Charlottesville, VA 22902 434-977-6406 Project Location: Latitude 38.071356 Longitude -78.499325' Located at the intersection of Georgetown Rd. and Hydraulic Rd., Off to the east of the intersection, County of Albemarle, Virginia (See USGS General Location Maps on following pages) Description: (Purpose and Type of Soil Disturbing Activities) The project proposes to develop commercial property at the intersection of Georgetown and Hydraulic Roads. Soil disturbing activities will include: installing erosion and sediment control devices, grading, fine excavation for construction of buildings and preparation for final stabilization and seeding. No residential activities are proposed for this site. APPROVED Project Start Date: August 1, 2020 by the Albemarle County Anticipated Project Completion Date: May 31, 2024 Community Development Department Date 'B-i-fit) File 0201°‘00001 1 CONTENTS PAGE General Location Maps 4-6 Contact Information 7 General Site Information 8 Sequence of Major Activities 8-9 Name of Receiving Waters 9 Special Conditions Related to TMDLs 9 Historic Districts 10 Endangered and Threatened Species and Critical Habitat Protection 10 Erosion and Sediment Controls 10 Stabilization Practices 10-14 Structural Practices 14 Vegetative Practices 14 Stormwater Management 14 Waste Materials 14 Hazardous Waste 14 Sanitary Waste 15 Offsite Vehicle Tracking 15 Timing of Controls and Measures 15 Certification of Compliance with Federal, State and Local Requirements 15 Maintenance and Inspection Procedures 15-16 Recordkeeping 16-17 I. Corrective Action and Forms 16 II. Grading and Stabilization Activities Log 17 III. Rainfall Tracking 17 IV. Log of Changes to the SWPPP 17 Comprehensive Site Compliance Evaluation- Post Construction 17 Non-Stormwater Discharges 17-18 Pollution Prevention Plan . 18-23 I. Inventory for Pollution Prevention Plan 18-19 II. Material Management Practices 19 III: Hazardous Products 20 • . IV.Product Specific Practices 20-21 V. Spills and Leaks ... 22 • VI. Spill Control Practices 22 VII. Spill Procedure 22-23 2 - .; ( Pollution Prevention Certification 24 Appendices 25 Appx A- Site Maps/Construction Plans(including ESC, PPP& SWM) Appx B- Copy of Construction General Permit Appx C- VSMP Registration Statement and Notice of Coverage Appx D- Delegation of Authority Appx E- Inspection Reports and Precipitation Log Appx F- Grading and Stabilization Log Appx G- Log of Changes and Update to SWPPP Appx H- Contractor/Subcontractor Certification and Agreements Appx I-Factsheets, Additional Information, Spill Reports Appx J- PPP Training Logs 3 -s -o p 'v 1 Berkmar CO0 (i--- -4,111> cr \`�' 6- m oc co 7' �c aca o° a °, o,, �_ G4 F_4-.ells, O 13 .� e a �a 44e Ada\ 4 Or ya�bsLn o O° ce iii \Q` iD • o - Charlottesville a a Or # u° ��° (eF Fashion Square °A° Westftek1,90, �p�. 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Designer: Jeremy Fox 999 2nd St. SE Suite 201 Charlottesville, VA 22902 434-977-0205 jofx@roudabush.com Responsible for site plan, erosion control and stormwater management plan preparation and design. SWPPP Roudabush, Gale, &Associates Preparer and 999 2nd St. SE Suite 201 Contact: Charlottesville, Virginia 22902 434-977-0205 Responsible for preparation of the SWPPP/PPP Pollution Prevention Team: The pollution prevention team is responsible for assisting the facility in developing, implementing, maintaining, inspecting and revising the facility's SWPPP. Below are the qualified personnel for the site. TBD SWPPP Availability: The Stormwater Pollution Prevention Plan, a copy of the VPDES permit, construction plans, and other materials referenced in this plan shall be retained at the project location. The SWPPP can be found on site near the construction entrance. Contact Roudabush, Gale, and Associates at 434-977-0205 with questions about the SWPPP notebook. 7 General Site Information Purpose: The purpose of the land-disturbing activity is build professional offices with supporting parking and utility infrastructure. Runoff Coefficient: The final coefficient of runoff is provided in the"Stormwater Management Plan" included in this SWPPP in Appendix A. Site Area: The total permitted site area is 1.05 acres and the estimated area to be disturbed is 0.88 acres. Site Map: A site map/vicinity map is provided on pages 4-6. Description of The current conditions of this lot consists of approximately I acre of vacant, gentle to Existing moderately steep sloping wooded land that generally drains downgradient west of the Site Conditions: parcel. Adjacent Areas: The Lot is bound by a mix of commercial and residential properties that run along public right-of-way. Offsite Land All excess material generated as part of the project shall be stored or spread within the Disturbance: approved land disturbance area or in an area approved by the County of Albemarle. Sequence of Major Activities: 1. After obtaining all required permits the contractor shall coordinate a pre-construction meeting, allowing 72 hours for its coordination. 2. Install construction entrance off of Hydraulic Rd. 3. Clearing and grubbing shall first be limited to the areas necessary to install silt fence and other perimeter controls.All perimeter controls must be made functional prior to any upslope land disturbance that takes place. 4. Prior to additional clearing and grubbing, the contractor shall coordinate inspections as required by the County of Albemarle. 5. Clear and grub the remainder of project area. 6. Stockpile topsoil within an area on the property or at a'location approved by Albemarle County Community Development. Install silt fence at the perimeter of stockpile(s) as necessary. 7. Denuded areas shall drain to an approved erosion control measures at all times during construction. 8. Permanent or temporary soil stabilization shall be applied to all denuded areas within seven days after final grade is reached on any portion of the site. Temporary soil stabilization shall be applied within seven days to denuded areas that may not be a final grade but will remain dormant for longer than 30 days. Permanent stabilization shall be applied to areas that are left dormant for more than one year. 9. Lime, fertilize and apply temporary or permanent seeding to all denuded areas immediately after achieving final grades. 10. All permanent slopes steeper than 3:1 shall receive stabilization with landscaping vegetation hardier than grass, which will not require mowing. 8 11. After proposed construction is completed and the site is completely stabilized, permission is to be obtained from the erosion control inspector for the removal of silt fencing and other remaining temporary erosion control measures. Name of Receiving Waters: Ivy Creek-Little Ivy Creek(JR07 (HUCO20802040202)) DEQ staff has determined that the proposed land-disturbing activity will discharge to a surface water identified as impaired or for which a TMDL wasteload allocation has been established and approved prior to the term of the general permit for(i) sediment or a sediment-related parameter or(ii) nutrients. Therefore,the following general permit(Part I.B.4)and SWPPP requirements (Part II.A.5) must be implemented for the land-disturbing activity: • Permanent or temporary soil stabilization shall be applied to denuded areas within seven (7)days after final grade is reached on any portion of the site. • Nutrients (e.g. fertilizers) shall be applied in accordance with manufacturer's recommendations or an approved nutrient 00management plan and shall not be applied during rainfall events. • Inspections shall be conducted at a frequency of(i)at least once every four(4) business days or(ii)at least once every five(5) business days and no later than 24 hours following a measurable storm event. In the event that a measurable storm event occurs when there are more than 24 hours between business days,the inspection shall be conducted on the next business day. • Representative inspections used by utility line installation, pipeline construction, or other similar linear construction activities shall inspect all outfalls. Special Conditions Related to TMDLs: For additional information on TMDLs please visit: 1) https://www.albemarle.org/upload/images/forms center/departments/Water Resources/forms/Albemarle County Local TMDL Action Plan 2016.pdf 2) https://www.albemarle.org/upload/images/forms center/departments/Water Resources/forms/Albemarle Chesapeake Bay TMDL Action Plan.pdf 3) https://www.albemarle.org/upload/images/forms center/departments/Water Resources/forms/Existing and New Sources.pdf 9 Historic Districts ® Identity/Pm , J,0p6 pHHe <an sboeM ,Oe n;,;%. Hydr aullc .,,,, c p +e ,,, E ,s Nn ,a W -1 aI' Po O Ar / •5 L O PO r/ aenAvat J � , o-e rJ,' SOUTHWEST f' ,r0. .q„ °Oj SAJe0 ef° J NOUN THINS RURAL , es� p C N�'MC` HISTORIC DISTR ICT 2 a ea�t'n 0, M,,,,.a/p001a0�� e� .�� �F`c „� : l�s„°.. Eastham , of a�J./e o f! tie t.:2'' r. 1 L /�� �,.. S t' fF� (C‘..,, J� e'; ice` I ^`! e!� Jcrwad"O o c c I `�! �/_ O ad JL / b pn�9�,. f µV 5 / �C 4. /�3 we,� tiol»ero"' i ) ° x The image(above) is compiled from information obtained from the Virginia Department of Historic Resources (DHR). Properties that are located within historic districts may be subject to certain development restrictions which can be found at: http://www.dhr.virginia.gov/. Green shaded regions depict the known historic districts that exist within Albemarle County near the proposed site. There are no known historic districts located within the proposed sites limits of disturbance at this time (outlined in yellow above). Endangered and Threatened Species and Critical Habitat Protection The United States Fish & Wildlife Service has identified species that are believed to or known to occur in Virginia. The list can be found on their Environmental Conservation Online System at: http://ecos.fws.gov/ecp0/reports/spec ies-1 isted-by-state-report?state=VA&status=listed There are no known endangered or threatened species located within the Georgetown Hydraulic proposed site limits of disturbance at this time. Erosion and Sediment Controls: Approved erosion and sediment control plans for Georgetown Hydraulic are incorporated by reference as part of this Stormwater Pollution Prevention Plan. Approved plans are included in this SWPPP binder- see appendix A. Stabilization Practices: 1. The purpose of the erosion control measures shown on these plans shall be to preclude the transport of all waterborne sediments resulting from construction activities from entering onto adjacent properties of state waters. If field inspection reveals the inadequacy of the plan to confine sediment to the project site, appropriate modifications will be made to correct any plan deficiencies. In addition to these notes, all provisions of the Virginia Erosion and Sediment Control Regulations shall apply to this project. 10 2. All erosion and sediment control measures shall be installed and maintained in accordance with the Virginia Erosion and sediment Control Handbook(3rd Edition, 1992) and Virginia Regulations 9VAC25-840 Erosion and Sediment control Regulations. The contractor shall be thoroughly familiar with all applicable measures contained therein which may be pertinent to this project. 3. Where construction vehicle access routes intersect paved public roads, provisions shall be made to minimize the transport of sediment by vehicular tracking onto the paved surface. Where sediment is transported onto a public road surface, the road shall be cleaned thoroughly at the end of each day. Sediment shall be removed from the roads by shoveling or sweeping and transported to a sediment control disposal area. If an excessive amount of soil is found tracked onto the public roadway, then a paved construction entrance, water tanker truck with two pressure washers and a settling area may be required by the erosion and sediment control program administrator. 4. A copy of the approved erosion and sediment control plan shall be maintained on the site at all times. 5. Sediment basins and traps, perimeter dikes, sediment barriers, and other measures intended to trap sediment onsite must be constructed as a first step in grading and be made functional before upslope land disturbance takes place. Sediment traps and basins shall be designed and constructed based upon the total drainage area to be served by the trap or basin. Earthen structures such as dams, dikes, and diversions must be seeded and mulched immediately after installation. Periodic inspections of the erosion control measures shall be made to assess their condition. Any necessary maintenance of the measures shall be accomplished immediately upon notification by the SWPPP Inspector and shall include the repair of measures damaged by any subcontractor including those of the public utility companies. 6. The contractor is responsible for installation of any additional erosion control measures necessary to prevent erosion and sedimentation as determined by the plan approving authority. 7. All disturbed areas are to drain to approved sediment control measures at all times during all land disturbing activities and during site development until final stabilization is achieved. 8. Sediment control measures may require minor field adjustments at time of construction to insure their intended purpose is accomplished. Division of code compliance approval will be required for other deviations from the approved plans. 9. Cut and fill slopes shall be designed and constructed in a manner that will minimize erosion. Slopes that are found to be eroding excessively within one year of permanent stabilization shall be provided with additional slope stabilizing measure until the problem is corrected. Concentrated runoff shall not flow down cut or fill slopes unless contained within an adequate temporary or permanent channel, flume or slope drain structure. 11 10. Whenever water seeps from a slope face, adequate drainage or other protection shall be provided. Contractor to notify engineer and county erosion control inspector. 11. During dewatering operations, water will be pumped into an approved filtering device. 12. The contractor shall place soil stockpiles at the locations shown on the SWPPP plan sheet for each area of construction, or as directed by design engineer. Soil stockpiles shall be stabilized or protected with sediment trapping measures immediately. The applicant is responsible for the temporary protection and permanent stabilization of all soil stockpiles on site as well as borrow areas and soil intentionally transported from the project site. 13. Prior to commencing land disturbing activities in areas other than indicated on these plans (including, but not limited to, offsite borrow or waste areas),the contractor shall submit a supplementary erosion control plan to the owner for review and approval by the plan approving authority. 14. Permanent or temporary soil stabilization must be applied to all denuded areas within 7 days after final grade is reached on any portion of the site. Temporary soil stabilization shall be applied within seven days to denuded areas that may not be at final grade but will remain dormant for longer than 14 days. Permanent stabilization shall be applied to areas that are to be left dormant for more than one year. Soil stabilization measures include vegetative establishment, mulching and the early application of gravel base material on areas to be paved. Contractor shall establish a stabilized site and not allow any sediment to exit the project limits. 15. Soil stabilization refers to measures which protect soil from erosive forces of raindrop impact and flowing water. Applicable practices include vegetative establishment, mulching and the early application of gravel base on areas to be paved. Soil stabilization measures should be selected to be appropriate for the time of year, site conditions and estimated duration of use. 16. When work in a live watercourse is to be performed, precautions shall be taken to minimize encroachment, control sediment transport and stabilize the work area to the greatest extent possible during construction.Non-erodible material shall be used for the construction of causeways and cofferdams. Earthen fill may be used for these structures if armored by non-erodible cover materials. Contractor shall follow the VESCH Chapter 3.25 Utility Stream Crossing requirements for the two intermittent stream crossing. 17. When a live water course must be crossed by construction vehicles more than twice in any six-month period, a temporary vehicular stream crossing constructed of non-erodible material shall be provided. 18. All applicable federal, state and local requirements pertaining to working in or crossing live water courses shall be met. 19. The bed and banks of a watercourse shall be stabilized immediately after work in the watercourse is completed. • 12 20. Underground utility lines shall be installed in accordance with the following standards in addition to other applicable criteria: a. No more than 500 linear feet of trench may be opened at one time. b. Excavated material shall be placed on the uphill side of trenches. c. Effluent from dewatering operations shall be filtered or passed through an approved sediment trapping device, or both, and discharged in a manner that does not adversely affect flowing streams or off-site property. d. Material used for backfilling trenches shall be properly compacted in order to minimize erosion and promote stabilization. e. Re-stabilization shall be accomplished in accordance with standards and specifications of the Virginia Erosion and Sediment Control Handbook f. Applicable safety requirements shall be complied with. 21. If disturbed area stabilization is to be accomplished during the months of November, December, January or February, stabilization shall be accomplished by permanently seeding the area with a seeding mixture that includes the seasonal nurse crop for the Piedmont area, which is Winter Rye. See Table 3.32-D for a list of site specific seeding mixtures for the Piedmont area. This is in accordance with Specification 3.32 from the Virginia Erosion and Sediment Control Handbook(VESCH). The seeding area will also need to be mulched in order to assist the growth of the seeding in the winter months (Specification 3.35 of the VESCH). For temporary seeding stabilization during these months, a 50/50 mix of annual ryegrass and winter ryegrass, as well as a mulching cover should be put down according to Specification 3.31 of the VESCH, Table 3.31-B. 22. The term seeding, final vegetative cover or stabilization, on this plan shall mean the successful germination and establishment of a stable grass cover from a properly prepared seedbed containing the specified amounts of seed, lime, and fertilizing in accordance with Specification 3.32, permanent seeding. Permanent vegetative cover shall not be considered established until a ground cover is achieved that is uniform, mature enough to survive and will inhibit erosion. 23. Inlet protection in accordance with Specification 3.07 shall be provided for all storm drain inlets that are made operable during construction so that sediment-laden water cannot enter the conveyance system without first being filtered or otherwise treated to remove sediment. 24. Before newly constructed stormwater conveyance channels or pipes are made operational, adequate outlet protection and any required temporary or permanent channel lining shall be installed in both the conveyance channel and receiving channel. 25. All temporary erosion and sediment control measures shall be removed within 30 days after final site stabilization or after the temporary measures are no longer needed, unless otherwise authorized by the local program administrator. Trapped sediment and disturbed soil areas resulting from the disposition of temporary measures shall be permanently stabilized to prevent further erosion and sedimentation. 26. If Applicable-As-built drawings must be provided for all detention/BMP facilities. Also upon completion,the construction of all detention/BMP facilities shall be certified by a professional engineer 13 who inspected the structure during construction. The certification shall state that to the best of his/her judgment, knowledge, and belief, the structure was constructed in accordance with the approval plans and specifications. Structural Practices: The following erosion and sediment control structural practices will be incorporated on the project site: 1. Construction Entrance (3.02) 2. Silt Fence/ Super Silt Fence (3.05) 3. Sediment Traps (3.13) 4. Sediment Basins (3.14) 5. Riprap (3.19) 6. Outlet Protection (3.18) 7. Inlet Protection (3.07) Vegetative Practices: 1. Dust Control (3.39) 2. Surface Roughening (3.29) 3. Top soiling/Stockpiling(3.30) 4. Permanent/Temporary Seeding(3.31 & 3.32) 5. Mulch (3.35) 6. Erosion Control Blankets (3.36) 7. Tree Protection (3.38) Stormwater Management: Stormwater runoff collected within the project will be treated by a stormwater detention system. See plan detail in appendix A. Waste Materials: All waste materials will be collected and stored in a proper receptacle in accordance with all local and State solid waste management regulations. All trash and construction debris from the site will be deposited in dumpsters. The trash will be hauled to an appropriate waste disposal site. No construction waste materials will be buried onsite. All project personnel will be instructed regarding the correct procedure for waste disposal. Hazardous Waste: All hazardous waste materials will be disposed of in the manner specified by the manufacturer and as required by local or State regulation. Site personnel will be instructed in these practices. 14 Sanitary Waste: All sanitary waste will be collected from the portable units as required by local and State regulation. Offsite Vehicle Tracking: Stabilized construction entrances will be provided to help reduce vehicle tracking of sediments. The paved street adjacent to the site entrance will be swept as needed to remove any excess mud, dirt or rock tracked from the site. Should the temporary construction entrance off of Hydraulic Rd. not be maintained properly or an excessive amount of silt found tracked onto the public roadway, then a pave construction entrance, water tanker truck with two pressure washers, and a settling area may be required by the erosion and sediment control program administrator. Dump trucks hauling material from the construction site will be covered with a tarpaulin. Timing of Controls and Measures: As indicated in the Stabilization Practices, permanent or temporary soil stabilization must be applied to all denuded areas within 7 days after final grade is reached on any portion of the site. Soil stabilization must also be applied to denuded areas which may not be a final grade but will remain dormant(undisturbed) for longer than 14 days. Soil stabilization measures include vegetative establishment, mulching and the early application of gravel base material on areas to be paved. Certification of Compliance with Federal, State and Local Requirements: The Stormwater Pollution Prevention Plan reflects State requirements for stormwater management and erosion and sediment control, as established in the Virginia Stormwater Management Handbook and Virginia Erosion and Sediment Control Manual. Maintenance and Inspection Procedures: Inspections of the construction site shall be made by the SWPPP Inspector, TBD, or by other qualified members of the Pollution Prevention Team. Erosion and sediment control measures identified in the plan shall be observed to ensure that they are still operating correctly. The contractor shall inspect all erosion control measures at least once every 4 or 5 business days and after each significant rainfall producing event. Any necessary repairs or cleanup to maintain the effectiveness of the erosion control devices shall be made within seven (7) days. Inspections shall be conducted (i) at least once every four(4) business days or(ii)at least once every five(5) business days and no later than 24 hours following a measurable storm event. In the event that a measurable storm event occurs when there are more than 24 hours between business days,the inspection shall be conducted on the next business day. These inspections shall cover disturbed areas that have not been finally stabilized, areas used for storage of materials that are exposed to precipitation, structural control measures, and locations where vehicles enter or exit the site. i 15 Where areas have been finally or temporarily stabilized or,runoff is unlikely due to winter conditions (e.g. site is covered with snow, ice or frozen ground exists) such inspections shall be conducted at least once every month. If weather conditions (such as above freezing temperatures or rain/snow events) make discharges likely, the operator shall immediately resume the regular inspection frequency. Reports summarizing each inspection shall be retained onsite as part of this Stormwater Pollution Prevention Plan. Each inspection report shall include the following items: a) The date and time of the inspection and when applicable, the date and rainfall amount of the last measurable storm event b) Summarized findings of the inspection c) The location(s) of prohibited discharges d) The location(s)of controlled measures that require maintenance e) The location(s) of control measures that failed to operate as designed or proved inadequate or inappropriate for a particular location f) The location(s)where any evidence identified under Park II G3a(7) exists g) The location(s) where any additional control measure is needed that did not exist at the time of inspection h) A list of corrective actions required (including nay changes to the SWPPP that are necessary) as a result of the inspection or to maintain permit compliance i) Documentation of any corrective actions required from a previous inspection that have not been implemented j) The date and signature of the qualified personnel and the operator or its duly authorized representative in accordance with Part III K of the general permit Recordkeeping I. Corrective Action and Forms The operator shall implement the corrective action(s) identified as a result of an inspection as soon as practicable but no later than seven days after discovery or a longer period as approved by the VSMP authority. If approval of a corrective action by a regulatory authority(e.g., VSMP authority, VESCP authority, or the department) is necessary, additional control measures shall be implemented to minimize pollutants in stormwater discharges until such approvals can be obtained. The operator may be required to remove accumulated sediment deposits located outside of the construction activity covered by this general permit as soon as practicable in order to minimize environmental impacts. The operator shall notify the VSMP authority and the department as well as obtain all applicable federal, state, and local authorizations, approvals, and permits prior to the removal of sediments accumulated in surface waters including wetlands. The contractor shall be responsible for the installation and maintenance of all erosion and sediment control practices for corrective actions. Corrective action notes can be found directly on the SWPPP reports. 16 II. Grading and Stabilization Activities Log Information on when major grading activities occur and when construction activities temporarily or permanently ceases on a portion of the site will be provided on the inspection reports for the project provided in the SWPPP updates section or on the grading and stabilization log provided in the appendix. III. Rainfall Tracking A blank rainfall data chart can be found in the appendix. It will be placed in the SWPPP notebook bi- monthly. IV. Log of Changes to the SWPPP The operator shall amend the SWPPP whenever there is a change in the design, construction, operation or maintenance that has a significant effect on the discharge of pollutants to surface waters and that has not been previously addressed in the SWPPP. A log of any changes to the SWPPP is provided in the appendix. Comprehensive Site Compliance Evaluation—Post Construction: Facility inspections will be conducted at least once a year by qualified personnel. The inspections will assess conditions at the facility that could impact stormwater quality and to assess the effectiveness of the BMPs that were constructed to control the quality of the stormwater discharges. Non-Stormwater Discharges: It is expected that the following non-stormwater discharges will occur from the site during the construction period. 1. Waters used to wash vehicles or equipment where soaps, solvents, or detergents have not been used and the wash water has been filtered, settled, or similarly treated prior to discharge. 2. Water used to control dust that has been filtered, settled, or similarly treated prior to discharge. 3. Potable water sources, including uncontaminated waterline flushing's/fire flow analysis. 4. Routine external building wash down where soaps, solvents or detergents have not been used and the wash water has been filtered, settled, or similarly treated prior to discharge. 5. Pavement wash waters where spills or leaks of toxic or hazardous materials have not occurred (or where all spilled or leaked material has been removed prior to washing); where soaps, solvents, or detergents have not been used; and where the wash water has been filtered, settled, or similarly treated prior to discharge. 6. Foundation or footing drains where flows are not contaminated with process materials such as solvents. 7. Uncontaminated excavation dewatering, including dewatering of trenches and excavations that have been filtered, settled, or similarly treated prior to discharge. 8. Landscape irrigation. 17 All non-stormwater discharges will be directed to sediment control measures prior to discharge. Pollution Prevention Plan I. Inventory for Pollution Prevention Plan: The materials or substances, other than sediment, listed below are expected to be present onsite sometime during construction: (a) Staging Area- Small Fueling activities, minor equipment maintenance, sanitary facilities, and hazardous waste storage (b) Materials Storage Area- General building materials, solvents, adhesives, paving materials, paints, aggregates,trash, etc. (c) Construction Activity- Paving, Curb/gutter installation, concrete pouring/mortar/stucco, and building construction (d) Concrete Washout Area Material/Chemical Physical Description Stormwater Location-Area where Pollutants used on site Pesticides (insecticides, Various colored to Chlorinated Herbicides used for fungicides, herbicides, colorless liquid hydrocarbons, noxious weed control rodenticides) powder, pellets or organophosphates, grains carbamates, arsenic Fertilizer Liquid or solid grains Nitrogen, phosphorous Newly seeded area Plaster White granules or Calcium sulphate, Home construction powder calcium carbonate, sulfuric acid Cleaning solvents Colorless, blue or Perchloroethylene, Equipment Cleaning yellow-green liquid methylene chloride, trichloroethylene, petroleum distillates Asphalt Black solid Oil, petroleum Streets and roofing distillates _ Concrete White solid/grey liquid Limestone, sand, pH, Curb and gutter, chromium sidewalk and building construction Glue, Adhesives White or yellow liquid Polymers, epoxies Home Construction Paints Various colored liquid Metal oxides, Stoddard Home Construction solvent, talc, calcium carbonate, arsenic Curing Compounds Creamy white liquid Naphtha Curb and gutter Hydraulic oil/fluids Brown oily petroleum Mineral oil Leaks or broken hoses hydrocarbon from equipment Wood preservatives Clear amber or dark Stoddard solvent, Timber pads and home brown liquid petroleum distillates, construction arsenic, copper, chromium 18 Gasoline Colorless, pale brown Benzene, ethyl Secondary or pink petroleum benzene,toluene, containment/staging hydrocarbon xylene, MTBE area or leaks Diesel Fuel Clear, Glue-green to Petroleum distillate, oil Secondary yellow liquid and grease, containment/staging naphthalene, xylenes area or leaks Antifreeze/coolant Clear green/yellow Ethylene glycol, Leaks or broken hoses liquid propylene, glycol, from equipment heavy metals (copper, lead, zinc) Sanitary Toilets Various colored liquid Bacteria, parasites, and Staging area viruses II. Material Management Practices: The following are the materials management practices that will be used to reduce the risk of spills or other accidental exposure of materials and substances to stormwate runoff. (a) Employee Training: Employee training with regard to material management practices is conducted at the site. Training includes discussions of spill response, good housekeeping, and other material management practices. Employee training generally occurs with each new employee once hired by the site contractor. Weekly tailgate training meetings are advised to ensure that as the site evolves and changes employees are up to date on all PPP practices. A training log to document these meetings can be found in Appendix J. (b) Good Housekeeping: The following good housekeeping practices will be followed onsite during the construction project. 1. All materials stored onsite will be stored in a neat, orderly manner in their appropriate containers. Materials which have the potential for contaminating runoff during storm events will be stored in their appropriate watertight containers, stored under a canopy, tarpaulin, shrink wrapped or otherwise precluded from direct exposure of precipitation. 2. Empty containers that may contain chemical residues shall be disposed of in accordance with State and Local regulations. 3. Products,where possible, will be kept in their original containers with the original manufacture's label. 4. Chemical or petroleum products will not be mixed with one another unless recommended by the manufacturer. 5. Whenever possible, all of a product will be used up before disposing of the container. 6. Manufacturer's recommendations for proper use and disposal will be followed. 19 7. The site superintendent will inspect daily to ensure proper use and disposal of materials onsite. III. Hazardous Products: These practices are used to reduce the risk associated with hazardous materials. Hazardous waste to include oil filters, petroleum products, paint, curing compounds and equipment maintenance fluids. Products will be kept in original containers unless they are not re-sealable. 2. Products will be stored in structurally sound and sealed containers and segregated from other non-waste materials. 3. Original specimen labels and materials safety data sheets will be kept on file; they contain important product information. 4. If surplus product must be disposed of, manufacturers and/or local and State recommended methods for proper disposal will be followed. IV. Product Specific Practices: The following product specific practices will be followed onsite: (a) Petroleum Products: 1. All onsite vehicles will be monitored for fluid leaks and will receive regular preventive maintenance to reduce the chance of leakage. 2. It is recommended that, if practicable, all refueling, repair and changing of equipment and vehicle fluids shall be conducted in a designated area, with the use of either spill buckets and/or fuel spill mats to reduce the potential for contamination. This area will be designed in a manner to reduce the potential for contamination of onsite resources. For refueling, repair and changing of equipment and vehicle fluids outside of the designated areas, care should be taken to avoid activities within+/- 50 feet of wetlands, streams,water bodies, tree preservation areas or any other environmentally sensitive areas. 3. Petroleum products will be stored in tightly sealed containers which are clearly labeled. 4. An area will be designated for the collection and storage of all chemical and storage of all chemical and petroleum based products and containers for those products. The containers shall be protected from rain events. These areas will be identified on the SWPPP/PPP if necessary. 5. Any asphalt substances used onsite will be applied according to the manufacturer's recommendations. 6. The project superintendent will regularly inspect the site to insure proper disposal methods of used antifreeze, oils, filters and other hazardous materials are followed. (b) Fertilizers: 20 Fertilizers used will be applied according to manufacturer's product standards. The contents of any partially used bags of fertilizer will be transferred to a sealable plastic container to avoid spills. (c) Paints, Curing Compounds, Soaps, Solvents, and Detergents: All containers will be tightly sealed and stored when not required for use. Excess paint will be properly disposed of according to manufacturers' instructions or State and local regulations. Discharges of soaps, solvents and detergents are prohibited. (d) Concrete Trucks and Wash Water from Construction Materials and Vehicles: Concrete trucks will only wash out or discharge surplus concrete or drum wash water at approved locations in accordance with State and local regulations. Wash water must be directed into a leak proof container or leak-proof settling basin that is properly designed. The liquid and hardened concrete must then be handled and disposed of properly and is not to be discharged. Washout areas are identified on the SWPPP/PPP Reference Drawing included with the"Final Construction Plans". An EPA concrete washout factsheet is provided in Appendix I. Water from vehicle wash stations (if needed) is to be directed to the nearest trap as shown on the approved erosion and sediment control plan before discharged. (e) Solid Waste: All waste materials will be collected and disposed of into two metal trash dumpsters in the staging area. Dumpsters will have a secure watertight lid, be placed away from stormwater conveyances and drains, and meet all local and state solid-waste management regulations. Only trash and construction debris from the site will be deposited in the dumpsters. All personnel will be instructed, during tailgate training sessions, regarding the correct procedure for disposal of trash and construction debris.Notices that state these practices will be posted in the office trailer and the individual who manages day-to-day site operations will be responsible for seeing that these practices are followed (f) Sanitary Waste: Portable lavatories are located on-site and are serviced on a regular basis by a contractor. They will be located in up-land areas away from direct contact with surface waters. Any spills occurring during servicing will be cleaned up immediately, including any contaminated soils, and disposed of according to all federal, state, and local regulations. (g) Minimization of Exposure to Precipitation and Storm Events In the event that precipitation is predicted onsite, construction activity operator to ensure that all building materials, building products, construction wastes,trash, landscape materials, fertilizers, pesticides, detergents, sanitary waste and other materials present onsite is protected from the runoff by the sure of covering tarps that securely fastened to eliminate blow off. 21 V. Spills and Leaks: This section normally contains a list of significant spills and significant leaks of toxic or hazardous pollutants that occurred at areas that are exposed to precipitation or that otherwise drain to a stormwater conveyance at the facility within the 3 year period immediately prior to the date of submission of a registration statement to be covered under this permit. No significant spills and/or leaks have occurred at the site of toxic or hazardous pollutants at areas that are exposed to precipitation. VI. Spill control Practices: In addition to the good housekeeping and material management practices discussed in the previous sections of this plan, the following practices will be followed for spill prevention and cleanup: 1. Manufacturers' recommended methods for spill cleanup will be clearly posted and site personnel will be made aware of the procedures and the location of the information and cleanup supplies. 2. Materials and equipment necessary for spill cleanup will be kept in the material storage area onsite. Equipment and materials may include but not be limited to brooms, dust pans, mops, rags, gloves, goggles, absorbent material (e.g. kitty litter, sand, sawdust) and plastic and metal trash containers. 3. All spills will be cleaned up immediately after discovery. 4. In the event of a spill of a hazardous substance, the spill will be immediately contained and the spill area will be kept well ventilated. Personnel will wear appropriate protective clothing to prevent injury form contact with a hazardous substance,during cleanup operation. 5. Spills of toxic or hazardous material will be reported to the appropriate State or local government agency, as required by regulatory standards. Call the agencies listed below to report any spills of toxic or hazardous material: Seminole Trail Fire Department: 434-973-1717 Albemarle County Police Department: 434-977-9041 Charlottesville Health Department: 434-972-6200 VA Department of Conservation& Recreation: 1-804-786-2094 VDEQ Valley Regional Office: M-F, 8:30-4:30 540-574-7800 VA Department of Emergency Services: 1-800-468-8892 Local VSMP Authority: M-F, 8:00-5:00 434-296-5832 VII. Spill Procedure 1) Check for hazards (flammable material, noxious fumes, cause of spill) - if flammable liquid, turn off engines and nearby electrical equipment. If serious hazards are present, leave the area and call 911. 2) Make sure the spill area is safe to enter and that it does not pose an immediate threat to health or safety of any person. 3) Stop the spill source. 4) Call co-workers and supervisor for assistance and to make them aware of the spill and potential dangers. 5) If possible, stop spill from entering drains (use absorbent or other material as necessary) 22 6) Stop spill from spreading (use absorbent or other materials necessary) 7) If spill material has entered a storm sewer or public waters; contact locality's storm sewer water department, locality's VSMP inspector, local VDEQ Office and VA Department of emergency services. 8) Clean up spilled material and do not flush area with water. 9) Properly dispose of cleaning materials and used absorbent material according to manufacturer specifications. *Spill report form and procedure can be found in Appendix I r it 23 Pollution Prevention Certification: I certify under penalty of law that I have read and understand that this document and all attachments were prepared in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information,the information submitted is, to the best of my knowledge and belief,true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. OWNER/OPERATOR: ( 4 P• 1 " 4 u COMPANY: 14‘id{C i GeorseireDuk>r1 LL�� TITLE: I aPAC L6— SIGNATURE: DATE: 7/ /ZA ) 22 Appendices APPX A- Site Maps/Construction Plans (Including Erosion and Sediment Control, Pollution Prevention Plan, and Stormwater Management Plan) APPX B-Copy of Construction General Permit APPX C- VSMP Registration Statement, Notice of Coverage Letter,Notice of Termination APPX D- Delegation of Authority APPX E- Inspection Reports and Precipitation Log APPX F- Grading/Stabilization Log APPX G- Log of Changes and Updates to SWPPP Log APPX H- Contractor/Subcontractor Certifications and Agreements APPX I- Factsheets, Additional Information, and Spill Reports APPX J- PPP Training Logs 25 13 m APPX A- Site Maps/Construction Plans (Including Erosion and Sediment Control Plan, Pollution Prevention Plan, and Stormwater Management Plan) 26 SITE DATA \ VS M P FOR OWNER: HYDRAULIC&GEORGETOWNLLC riFLI N 400 LOCUST AVENUE, SUITE 3 -" CHARLOTTESV/LLE, VA 22902 DEVELOPER: BMC HOLDINGS GROUP LLC 0 i o 0 400OLOCUST AVE,L SUITE 3 GEORGETOWN HYDRAULIC CHARLOTTESVILLE, VA 22902 a=' 3 PLAN PREPARE.: ROUDABUSH, GALE, &ASSOCIATES ¢ a,, o ¢Z U o 172 SOUTH PANTOPS DRIVE CNARLOT7ESVlLLE, 22911 m (434)-977-8121 r� Q Z TAX MAP PARCEL No: O60F0-00-00-003 VA JACK JOUETT MAGISTERIAL DISTRICT SHEET INDEX QOI PARCEL AREA: 1.05 ACRES SHEET 1 COVER SHEET �" w a ZONING: NEIGHBORHOOD MODEL DISTRICT. PARCEL IS SUBJECT TO ZMA2006-14 WITH ASSOCIATED PROFFERS il 3- SHEET 2 EXISTING CONDITIONS/SOILS MAP .•7 a Q AND CODE OF DEVELOPMENT; AIRPORT OVERLAY AND ENTRANCE CORRIDOR OVERLAY DISTRICTS ALB E MAR LE CL.JNTY VI RG I N IA a N �"> o PROPOSED USE: PROFESSIONAL OFFICES SHEET 3 EROSION CONTROL PLAN PHASE I Ca , BUILDING AREA: 16,815 GROSS SF, MAXIMUM ALLOWED W P 0201900061 SHEET 4 EROSION CONTROL PLAN PHASE II 0 "'�' 14,289 GROSS SF, PROPOSED(INCL. PARKING LEVEL) �0 n F BUILDING HEIGHT ALLOWED: 2 STORIES: 50'MEASURED FROM FRONT FACADE SHEET 5 EROSION CONTROL NARRATIVE F:•1 1 r U 3 STORIES: 60'MEASURED AT THE BACK TO INCLUDE BASEMENT SHEET 6 EROSION CONTROL NOTES&DETAILS i7 BUILDING HEIGHT PROPOSED: FRONT 32'MEASURED FROM FINISHED FLOOR TO PARAPET !- \Yl \.w \f / N ;:l'''.1477,r � 3 ire `r PARKING SETBACK: ID'MINIMUM r t' 13+ 1.o -��,+^ , lSHEET 7 SLUM NOTES&DETAILS BUILDING SETBACKS (IN ACCORDANCE WITH THE GENERAL DEVELOPMENT PLAN) i(( �/�% c, i'_M�� �� �� SHEET 8 CHANNEL PROTECTION COMPLIANCE (MINIMUM) FRONT SETBACKS FROM BUILDING CORNERS: 9.63'&13.47' _ 8 •�'�FRONT SETBACKS FROM CENTER OF BUILDING: 15.22'&21.85' '� � �"( ��F�" SHEET 9 FLOOD PROTECTION COMPLIANCE BUILDING SETBACKS FROM THE RA ZONING: 47.50' •4m ` �`\ �7 �� F /'Sep o_ AREA SUMMARIES: TOTAL BUILDING COVERAGE=6,765 SF(159,) et. f`%Ste,,1 .+ h>y '. - TOTAL IMPERVIOUS COVERAGE(INCL BUILDING)=20,765 SF(45Z) N"o� `'. ♦ �� �I1/,~� k�` I�/ "itQ A • o TOTAL OPEN SPACE=24,973 SF(55%) D \ 7 4,11���3hitti .- � Fi % CSC?Ottc I 'MAGISTERIAL DIS RICP JACK JOUETT MAGISTER/AL DISTR/CT I 11��f.0 larririra.L,t �y�1.'�'i �3r ►J,... Ar iIliiii -r:0 CONTRACTORS RECORD DRAWING REQUIREMENTS: WATERSHED: IVY CREEK(A WATER SUPPLY PROTECTION AREA) haErJC t r4 NOR• ' ,,, �i � �S+V3Y SSG ; �I A. (�HZ CONTRACTOR SHALL KEEP ACCURATE RECORDS OF ANY CHANGES SUBSTITUTIONS, ALTERATIONS, ""E..... , f - ip(C]y C:���'av��W. ,_, ��`((( \T�/ `,� VARIATIONS OR UNUSUAL CONDITIONS ENCOUNTERED OR IMPLEMENTED WHILE ENGAGED ON THIS o BOUNDARY SOURCE: SUBDIVISION PLAT, LOT I, "GEORGETOWN GREEN"PREPARED BY W.S. ROUDABUSH, DATED JUNE 20, 1967, .":- .0„ �� ��G�,��.d.. ,�, F•,•• p)� .;,d°� `« PROJECT THESE RECORDS SHALL BE IN THE FORM OF 'REDLINES". REDLINES'SHALL REFER TO THE RECORDED AT DB 440 PG 93. ` ♦ I. y `" I lj•• '1�4'14.A {`yiV../ CONTRACTOR'S HAND ANNOTATIONS USING RED COLORED PEN/PENCIL TO DEPICT ACTUAL CHANGE. CO • - � j. i i 4*"..... SUBSTITUTION, OR CONDITION. O z TOPOGRAPHY.' TAKEN FROM GENERAL DEVELOPMENT PLAN BY DOMINION DEVELOPMENT RESOURCES, LLC(2006); TREE ,i �•' r �.{' y� V . `� �'�7� � y SURVEY BY ROUDABUSH, GALE&ASSOCIATES, JANUARY 2019; WATERLINE LOCATION CHECK BY ROUDABUSH, rr�� F� '•, *� y"-4��h7'•e. �L' /�/"�,°/� �Cry��, PRIOR TO CONTRACTOR REQUESTING PARTIAL OR FULL PAYMENT, CONTRACTOR SHALL PROVIDE THE fi� : .1- �. % - • N/ U_ OWNER WITH AN UP-TO-DATE CONTRACTOR'S RECORD DRAWING SPECIFICALLY, THIS SET OF PLANS, GALE&ASSOCIATES, SEPTEMBER 2019. Y T , , �� , i ' IIN s N ,/ A �`y«� j� i;; O��fa^� ISSUED TO THE CONTRACTOR AS FINAL CONSTRUCTION DRAWINGS, SHALL BEAR THE REDLINE" BENCHMARK: TRAFFIC BOX 614.79. TAKEN FROM GENERAL DEVELOPMENT PLAN BY DOMINION DEVELOPMENT RESOURCES LLC . C�X • \ C MARKINGS LISTED BELOW AS WELL AS THE CONTRACTOR (AGENT OR SUPERINTENDENT) SIGNATURE zo (2006) { 4`- '~� �f /� `- ...,..„,4\\ZZZLLL� i; # ' � AND CERTIFICATION BELOW. F 2 2 y'�,•', r K-',-`.c`,///� i 1;• s' •;' ,` ✓, • REDLINES SHOULD ALWAYS BE ACCURATE NEAT, LEGIBLE, DATED AND REASONABLY SCALED 6 0 0 DATUM: HORZ-: NAVD 88 VERT-: NAD83 --1 1 14'J �:i P {/ ,� �� ► '.��,'74'`•V"%� "T\ o`+' • ADD LARGE RED LETTERS TO TITLE SHEET WITH 'CONTRACTOR'S RECORD DRAWING' INCLUDING FLOODPLA/N: THIS PROJECT IS LOCATED WITHIN "ZONE X"AS SHOWN ON FLOOD INSURANCE RATE MAP. COMMUNITY PANEL - Y 4iPawt At. 4,4,4 s ;. T ��* « CONTRACTOR'S NAME, DATE, AND OTHER RELEVANT INFORMATION o 0 ��a� ",r, i� C CEi i �a''•NUMBER 510003C 0279 D. EFFECRVE DATE• FEBRUARY 4. 2005. •CONTRACTOR'S REPRESENTATIVE OR SUPERINTENDENT SHALL INITIAL EACH SHEET. IF A SHEET PARKING REQUIRED: P£R GENERAL DEVELOPMENT PLAN, 1 SPACE PER 200 SF NET LEASABLE AREA = 9,376 200= 47 SPACES r 1 ;Ej ,VW!ra 1N• -;% )e �+s HAS NOT BEEN CHANGED AT ALL OR NO MARK HAS BEEN ADDED, LABEL THE SHEET ONLY 'NO / 1( ` \�±v;- / J'�YJ�I� ��Cf�,`y,��/ � CHANGES' �, PARKING PROVIDED: 50 PARKING SPACES TOTAL /♦T�tr� ���� Q � iy �! tQ;'=: ` o .� fr f _'�rI �' �FIJ�J� yJii,���(S• - ��. �• •IF A SHEET HAS BEEN CHANGED OR MODIFICATIONS HAVE BEEN ADDED, LABEL IT 'REVISED' _ 2 ADA VAN ACCESSIBLE SPACES.. r i I r, ky d 4:+ I¢ � � s •USE WRITTEN EXPLANATION TO DESCRIBE CHANGES. REFER TO SPECIFIC ACTIONS INSTEAD OF m\ •3 SPACES RESERVED FOR IMP 6OF-1 PER OB 1591 PG 160 IV o �R•'•.�, tc•aF'- r�� S"ACCESSIBLE PARKING SPACES AND ACCESS ISLES SHALL NOT HAVE A SURFACE SLOPE GREATER THAN 1:48. I I eeiA 7G uy� g�J r. nia� REFERENCING CHANGE ORDER NUMBERS OR RELATED DOCUMENTS z.,r ACCESS ISLES SHALL BE AT THE SAME LEVEL AS THE PARKING SPACE THEY SERVE A ��b�U61 �1�-c;1 •USE CLEAR LETTERING RETAINING WALLS RETAINING WALLS GREATER THAN 3 FEET IN HEIGHT REQUIRE A SEPARATE BUILDING PERMIT. WALLS CD \\� �I"='-�411 jV 1'r17f0.,,- � • NEVER REMOVE OLD VALUES OR DETAILS, JUST REDLINE OR Ti'THROUGH THEM, IF THERE IS NO 'DESIGNED BY.JLF(VSMP) • EXCEEDING 4 FEET IN HEIGHT REQUIRE AN STAMPED ENGINEERED DESIGN. PLEASE SEE RETAINING WALL z ''_ . 4.!'••: 1,8 44e�'!��' ROOM FOR THE NEW VALUE, YOU CAN GO TO THE SIDE AND REDLINE THE REPLACEMENT VALUE. DRAWN BY: JLFNVN DESIGN BY OTHERS UNDER SEPARATE COVER. ---I I .,, , .(L1-`__.:• �f-�-,g e _Q_HECKED BY: JLT y; _ ` •PROVIDE THE REDLINE DETAILS OF CHANGES DR ADDITIONAL INFORMATION, INCLUDING BUT NOT -< .-;tK 1 ,,, ' ^F-'-.a�,4. • LIMITED TO FABRICATION, ERECTION, INSTALLATION, LOCATION, SIZING, MATERIAL, DIMENSION, !.< •� r 'S-'� It""xJ �1�!. ADDITIONS. RELOCATIONS, SUBSTITUTIONS, ETC NO EVIDENCE OF A BURIAL SITE WAS FOUND ON SUBJECT PARCEL. e •t �;•', ev 'V ' I��,:,«[ lt, 4$PyTB Op `r < � •.� sn��`'�.at��\��.�p r„•�n«� •BE SPECIFIC WHEN MAKING NOTES ; UNDERGROUND UTILITIES, SHOWING EXACT LOCATION, 0 �c NO STREAM BUFFER(S)ARE PRESENT ON THE SUBJECT PARCEL. 'I'° fir• •0 u/r�j. V, ��'' •�42 y 1 DEPTH, AND MATERIAL USED (EXAMPLE: SEWER LATERALS) �� z V ,,�nA`,,y'�r1r,.� V�r? :��Y•r'.. •PROVIDE ALL NECESSARY INFORMATION OF CONTRACTOR'S DESIGNED SYSTEMS OR SUBSTITUTIONS c0, THE SUBJECT PROPERTY IS NOT LOCATED WITHIN AN AGRICULTURAL-FORESTAL DISTRICT. O v�`0 wy. 't■:1�• fit, �+ T/ MAP T7 �� �It�`�,I••'° i�'.�A .13A°- VICINITY 1 MAP •CROSS OUT ANY PLAN REFERENCE TO 'APPROVED EQUAL' AND REPLACE WITH ANY SPECIFIC THE SUBJECT PROPERTY IS LOCATED WITHIN THE JURISDICTIONAL AREA FOR PUBLIC WATER AND SEWER. -I I 4►�'tAe ♦• G, . i) INFORMATION OF VARIANCE USED DURING THE CONSTRUCTION PROCESS Jimmy L.Taggart .. f _ .'.C�ePi j C, SCALE: 1°=1000 FEET • ANY CHANGES IN INVERT ELEVATIONS, GRADE MODIFICATIONS, SLOPES, AND RELATED 'o 22841 ;44, GENERAL NOTES INFORMATION ON PIPING UTILITIES, EARTHWORK, ETC SHALL BE REDLINED ese Y'o' 1. THE CONTRACTOR SHALL BE RESPONSIBLE FOR OBTAINING ALL NECESSARY PERMITS, INSPECTIONS, •RECORD ALL UNEXPECTED OBSTRUCTIONS, COMPLICATING FACTORS. UNSUITABLE CONDITIONS Toxa>.s BONDS AND OTHER APPROVAL RELATED ITEMS IN ACCORDANCE WITH LOCAL AND STATE POLICY. GENERAL EROSION CONTROL NOTES FOUND IN THE PROJECT AREA INCLUDING ROCK, UNUSUAL TOPSOIL CONDITIONS. BURIED DEBRIS, PRIOR TO COMMENCEMENT OF CONNECTION TO ANY EXISTING ROAD, A PERMIT FOR SAID ETC. . WORK AREA PROTECTION&MAINTENANCE CONSTRUCTION SHALL BE OBTAINED FROM THE VIRGINIA DEPARTMENT OF TRANSPORTATION 1.ALL FENCES REQUIRED TO BE REMOVED OR DISTURBED BY CONSTRUCTION SHALL BE SALVAGED.STORED,PROTECTED AND RE-INSTALLED BY CONTRACTOR AT THE DIRECTION OF AND LOCATION DESIGNATED BY ATTACH OR INCLUDE ANY SHOW DRAWINGS OR SUPPLEMENTAL INFORMATION TO THE (HEREAFTER ABBREVIATED VDOT) THE PROJECT MANAGER.IF SUCH FENCE MATERIAL CANNOT BE REUSED DUE TO DAMAGE CAUSED BY CONTRACTOR.CONTRACTOR SHALL INSTALL NEW FENCE OF THE SAME TYPE OF MATERIAL.TEMPORARY CONTRACTOR'S RECORD DRAWING Z 2. ALL PAVING AND DRAINAGE RELATED MATERIALS AND CONSTRUCTION METHODS SHALL CONFORM TO FENCING REQUIRED BY PRIVATE PROPERTY OWNERS SHALL BE PROVIDED BY CONTRACTOR.CONTRACTOR IS ADVISED TO CONTACT PROPERTY OWNERS AT LEAST FORTY-EIGHT(48)HOURS IN ADVANCE OF CHANGES MADE AS A RESULT OF ANY REGULATORY OR OWNER INSPECTION PROCESS CURRENT STANDARDS AND SPECIFICATIONS OF VDOT UNLESS OTHERWISE NOTED REMOVING ANY FENCE IN ORDER TO COORDINATE RELOCATION AND/OR PROTECTION OF ANY ANIMALS.AND TO ESTABLISH AND CONFIRM WITH THE OWNER THE PRE-CONSTRUCTION CONDITION OF ANY FENCE • 3. EROSION AND SEDIMENT CONTROL MEASURES SHALL BE PROVIDED IN ACCORDANCE WITH THE TO BE REMOVED,DISTURBED OR REPLACED. CL U APPROVED EROSION AND SEDIMENT CONTROL PLAN AND SHALL BE INSTALLED PRIOR TO ANY 2.CONTRACTOR IS PERMITTED TO WORK IN THE PUBLIC RIGHT-OF-WAY(FOLLOWING ISSUANCE OF VDOT APPROVAL)AND ANY TEMPORARY OR PERMANENT EASEMENT(FOLLOWING VERIFICATION OF EXISTENCE OF CERTIFICATION STATEMENT: (- CLEARING, GRADING OR OTHER CONSTRUCTION. EASEMENT)SHOWN ON THE PLANS HOWEVER,CONTRACTOR SHALL NOTIFY PROPERTY OWNER(S) FORTY-EIGHT(48)HOURS PRO.TO WORKING ON ANY PRIVATE PROPERTY TO GAIN AND COORDINATE ACCESS z 4. THE CONTRACTOR SHALL VERIFY THE PROPOSED LAYOUT, THE VERTICAL DEPTHS AND LOCATION OF AND TO DETERMINE A STORAGE AREA FOR MATERIALS IF NEEDED.COORDINATION OF ACCESS TO PUBLIC RIGHT-OF-WAY AND STORAGE OF MATERIALS THEREON SHALL BE COORDINATED WITH SOOT AND THE THIS HAND-MARKED SET OF DRAWINGS HAS BEEN "REDLINED" TO PROVIDE ACCURATE DETAILED W D PRIVATE UTILITIES WITH ITS RELATIONSHIP TO THE EXISTING SITE SURVEY. THE CONTRACTOR SHALL PROJECT MANAGER.CONTRACTOR'S FAILURE TO SO NOTIFY AND COORDINATE WITH PROPERTY OWNERS AND/OR THE PROJECT MANAGER MAY RESULT IN DELAYS RECORD OF ANY SUBSTANTIVE CHANGES TO THE APPROVED DESIGN DRAWINGS. ANY ITEM NOT ALSO VERIFY ALL DIMENSIONS, SITE CONDITIONS, AND MATERIAL SPECIFICATIONS AND SHALL NOTIFY 3.CONTRACTOR SHALL.AT HIS EXPENSE.MAINTAIN THE WORK SITE IN A CLEAN AND ORDERLY APPEARANCE AT ALL TIMES.ALL DEBRIS AND SURPLUS MATERIAL COLLECTED SHALL BE DISPOSED OF OFF THE 'REDLINED' ON THIS PLAN SET OR SUBSEQUENT PAGES SHOULD BE CONSIDERED TO BE w Q THE OWNER AND ENGINEER OF ANY ERRORS. OMISSIONS OR DISCREPANCIES BEFORE COMMENCING WORK SITE BY CONTRACTOR,AT HIS EXPENSE 'CONSTRUCTED IN ACCORDANCE WITH THE DESIGN AS SHOWN" CO 4.EXISTING LAWNS,TREES,SHRUBS,FENCES.UTILITIES.CULVERTS,WALLS,WALKS,DRIVEWAYS,POLES.SIGNS,RIGHT-OF-WAY MONUMENTS,MAILBOXES AND THE LIKE SHALL BE PROTECTED FROM DAMAGE DURING Q Q OR PROCEEDING WITH WORK. THE WORK.ANY DAMAGE CAUSED TO SUCH ITEMS SHALL BE REPAIRED OR REPLACED BY CONTRACTOR AT NO ADDITIONAL COST PROPERTY PINS DISTURBED BY CONTRACTOR THAT ARE NOT SHOWN ON THE F, 5. DEVIATIONS FROM OR CHANGES TO THESE PLANS WILL NOT BE ALLOWED UNLESS APPROVED BY PLANS TO BE DISTURBED SHALL BE RESTORED BY A LICENSED SURVEYOR AT CONTRACTOR'S EXPENSE. - z (7 >' THE ENGINEER 5.CONTRACTOR SHALL EMPLOY EROSION CONTROL DEVICES AND METHODS AS REQUIRED TO MEET THE REQUIREMENTS AND INTENT OF THE LOCAL EROSION CONTROL ORDINANCE.CONTRACTOR SHALL PROVIDE > j 6 THIS PLAN DOES NOT GUARANTEE THE EXISTENCE OR NON-EXISTENCE OF UNDERGROUND UTILITIES THE NECESSARY DIVERSION DITCHES,DIKES OR TEMPORARY CULVERTS REQUIRED TO PREVENT MUD AND DEBRIS FROM BEING WASHED ONTO THE STREETS OR PROPERTY CONTRACTOR'S VEHICLES SHALL BE NAME TITLE DATE Q I LU PRIOR TO ANY CONSTRUCTION OR EXCAVATION THE CONTRACTOR SHALL VERIFY THE EXISTENCE KEPT CLEAN TO PREVENT MUD OR DUST FROM BEING DEPOSITED ON STREETS.NO AREA SHALL BE LEFT DENUDED FOR MORE THAN SEVEN(7)CALENDAR DAYS. < I AND LOCATION OF, OR THE NON-EXSITENCE OF. UNDERGROUND UTILITIES. THE CONTRACTOR SHALL ¢Z U) VEGETATION BE RESPONSIBLE FOR NOTIFYING "MISS UTILITY(1-800-552-7001). LLJ /, > m 7. THE CONTRACTOR IS REQUIRED TO TAKE PRECAUTIONARY MEASURES TO PROTECT ANY EXISTING I.PRIOR TO REMOVING ANY VEGETATION,CONTRACTOR SHALL MEET WITH THE PROPERTY OWNERS AND THE PROJECT MANAGER TO REVIEW THE LIMITS OF CONSTRUCTION AND OBTAIN PERMISSION TO REMOVE > W VEGETATION REQUIRED TO DO THE WORK 1- UTILITIES O ' NOT OF RECORD OR NOT SHOWN ON THESE PLANS THE CONTRACTOR SHALL BEFOR' (CONTRACTOR) > Ci O 2.TREE AND PLANTH 0 NOTO OR BRANCHES THAT MAY INTERFERE WITH THE WORK SHALL TOR TRIMMEDIOR CUT ONLY WITH THE APPROVAL OF THE PROJECTLA MANAGER.ONANY TREES OR PLANTS WHICH ARE SHOWN RESPONSIBLE FOR REPAIRING, AT HIS EXPENSE. ANY EXISTING UTILITIES DAMAGED DURING TO REMAIN THAT 00 INTERFERE WITH THE WORK,BUT ARE DAMAGED BY CONTRACTOR OR HIS SUBCONTRACTORS.SHALL BE REPAIRED OR REPLACED BY CONTRACTOR AT NO ADDITIONAL COST. 0 CONSTRUCTION. IF A UTILITY IS DAMAGED DURING CONSTRUCTION, STOP WORK IMMEDIATELY AND 3. CONTRACTOR SHALL CLEAN UP,RESTORE.SEED AND MAINTAIN ALL DISTURBED AREAS IMMEDIATELY UPON COMPLETION OF WORK ON EACH SITE.TOPSOIL.SEED.FERTILIZER AND MULCH SHALL BE PLACED IN 11�I NOTIFY THE ENGINEER. ACCORDANCE WITH ESC AUTHORITY STANDARDS ON ALL DISTURBED AREAS.A PERMANENT STAND OF GRASS ADEQUATE TO PREVENT EROSION SHALL BE ESTABLISHED PRIOR TO FINAL ACCEPTANCE. Li] p 8 CONTRACTOR AGREES THAT HE SHALL ASSUME SOLE AND COMPLETE RESPONSIBLY FOR JOB SITE 4.THE ACT OF RESEEDING SHALL NOT QUALIFY AS'STABILIZED' THE CONTRACTOR SHALL BE RESPONSIBLE TO ESTABLISH VEGETATION.NOT SIMPLY APPLY SEED AND MATERIALS O 0 U CONDITIONS DURING THE COURSE OF CONSTRUCTION OF THIS PROJECT, INCLUDING SAFETY OF ALL PERSONS AND PROPERTY; THAT THIS REQUIREMENT SHALL APPLY CONTINUOUSLY AND NOT BE ~ CC LIMITED TO NORMAL WORKING HOURS: AND THAT THE CONTRACTOR SHALL DEFEND, INDEMNIFY AND SWM COMPLIANCE SUMMARY REGARDING WATER QUANTITY ANALYSIS: 0 HOLD THE OWNER AND THE ENGINEER HARMLESS FROM ANY AND ALL LIABILITY, REAL AND COMPLIANCE OF 9VAC25-870.0.1 B(CHANNEL PROTECTION). Q LL.I ALLEGED, IN CONNECTION WITH THE PERFORMANCE OF WORK ON THIS PROJECT, EXCEPTING FOR z LIABILITY ARISING FROM "THE SOLE NEGLIGENCE OF THE OWNER OR THE ENGINEER". STORMWATER RUNOFF COLLECTED WITHIN THE PROJECT WILL BE CONVEYED THROUGH A STORMWATER PIPE NETWORK TO AN UNDERGROUND IN ACCORDANCE 1WTH CHANNEL PROTECTION SECTION 3.3 A)OF 9VAC25-870-66 OF VIRGINIA LAW; THE MAXIMUM PEAK FLOW RATE FROM THE ONE-YEAR 24-HOURCD 9. ANY DAMAGE TO EXISTING PHYSICAL FEATURES(WALKS, LIGHTS, TREES, SHRUBS, ETC) SHALL BE DETENTION SYSTEM(BY OTHERS) STORM FOLLOWING THE LAND- DISTURBING ACTIVITY APPEARS TO BE IN ACCORDANCE WITH THE ENERGY BALANCE METHODOLOGY 0 ()DEVELOPED 5 IF•(QPRE-DEVELOPED•RVPRE-DEVELOPED)/RVDEVELOPED THE RESPONSIBILITY OF THE CONTRACTOR. REPAIRS OR REPLACEMENT SHALL BE MADE AS CC NECESSARY AT NO COST TO THE OWNER. REGARDING WATER DUALITY ANALYSIS: lYR OOEVELOPEO 5 IF.• (7YR()PRE-DEVELOPED •RVPRE-DEVELOPED)/RVDEVELOPED 10. ALL TURF AREAS THAT ARE IMPACTED OR DISTURBED BY THE CONTRACTOR VEHICLES, EQUIPMENT 9yAC25-870-63. WATER QUALITY DESIGN CRITERIA REQUIREMENTS. 002 5 090• (027 0 OR ACTIVITY SHALL BE REPAIRED, REGRADED, AND RESEEDED. 1.NEW DEVELOPMENT, THE TOTAL PHOSPHORUS LOAD OF NEW DEVELOPMENT PROJECTS SHALL NOT EXCEED 0.41 POUNDS PER ACRE PER 0.02 5 0.04 11 PARKING FOR THE CONTRACTOR'S VEHICLES SHALL BE COORDINATED THROUGH THE OWNER THE YEAR, AS CALCULATED PURSUANT TO 9VAC25-870-65.CALCULATIONS SHOWN ON THIS PLAN WERE DETERMINED FROM ACCEPTABLE OWNER IS NOT RESPONSIBLE FOR THE LOSS OF ANY MATERIAL STORED AT THE SITE. PARKING OF METHODOLOGY"DEO VRRM FROM NEW DEVELOPMENT COMPLIANCE SPREADSHEET-VERSION 3.0 COMPLIANCE OF 9VAC25-870-66.0(FLOOD PROTECTION): DATE' OCTOBER 25,2019 EMPLOYEE VEHICLES WILL BE ACCOMMODATED AT THE SITE. SCALE. N/A 12 THE POSTED SPEED LIMIT SHALL BE 5 MPH BELOW DESIGN SPEED. CONCLUSION: IN REFERENCE TO FLOOD PROTECTION SECTION C 1), THE SITE'S POINT OF DISCHARGE RELEASES CAPTURED STORMWATER INTO A CONVEYANCE SYSTEM THAT,FOLLOWING 13. ALL ROADWAYS WITHIN THIS DEVELOPMENT ARE TO REMAIN PRIVATE AND ARE NOT TO BE THE WATER DUALITY PORTIONS OF THIS PLAN WILL BE SATISFIED WITH PURCHASING 0,81 IB/YR OF OFFSITE NUTRIENT CREDITS IN THE SAME LAND DISTURBING ACTIVITY,CONFINES THE POST-DEVELOPMENT PEAK FLOW RATE FROM THE 10-YEAR 24-HOUR STORM EVENT WITHIN THE STORM WATER CONVEYANCE JOB- GTH MAINTAINED BY MOOT OR LOUISA COUNTY OF ADJACENT HYDROLOGIC UNIT CODE(02080204).COMPLIANCE OF 9VAC25-870-65.F OFFSITE ALTERNATIVE TAW 9VAC25-870-69 SYSTEM O/10POST-DEVELOPED 5 0/10PRE-DEVELOPED FILE- 190125 14. ALL PAVEMENT MARKINGS & SIGNAGE SHALL BE IN ACCORDANCE WITH THE CURRENT VDOT & PURCHASE OF NUTRIENT OFFSET CREDITS IS PROPOSED AND AFFIRMED. ` MUTCD REGULATIONS. O/1GPOST-DEVELOPMENT= 0.09 Os 5 0/10PRE-DEVELOPMENT- 1.23 Os _21 SHEET. 1 OF 9 . - , . / • . 3 , \ , 1 1 i ---/ 1 1 • i , . . , , .. \ \ \ \ \ I \ \ / ‘,./ \/ / // // \\ \ It I \ \\\ \ /‘ \ N ,., \ N _- -__ ---- \ -_ -- \ . N... N c /-...._ . 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FOR 4•6 ....) t.. 0 cf,g 1 3/20/2020 COUNTY COMMENTS GEORGETOWN HYDRAULIC ..,..., E- ,;', T,5. 2 8/12/2020 COUNTY COMMENTS A PROFESSIONAL CORPORATION ._,.,1 po• r '`...,.. ta - r5 SERVING VIRGINIA SINCE 1956 COUNTY OF ALBEMARLE,VIRGINIA 'ti. P64 P ' PHYSICAL MAILING ' i 999 SECOND so SE 435 MERCHANT WALK SO,SUITE 300-159 a- .t, .11.1 LHARLOTIESVILLE VA 22902 CHARLOTIESVILLE,VA 22902 w RI EXISTING CONDITIONS/SOILS MAP `4 v I,' PHONE 434-477-0295 WVVW ROLIDABUSH COM ,/ _ 20 0 20 40 60 ■ _ n _ __ SCALE: I"=20' y w o=, / it \ -/-I III i,1 F> , I 1 y 0O a 1" 1• Q O o a'? o h. 1 1. '11 Q? �= o j -1 1 ,1 WATER TANK WITH (2) W O a o _ - _ I POWER WASHERS SHALL BE /' - _ 1 STORED ONSITE AT THE -1 Z K _ ,1-. 1 CONSTRUCTION ENTRANCE - - Z ONSITE CLEARING OF TREES WITHIN _ 1 1 - ---- m / -THE CONSERVATION AREA SHALL BE _ '-I I _ m RESTRICTED TO THOSE ONLY TMP 60E-1 = 1 Ate+ DYNAMIC INVESTMENT V) 0 REQUIRED FOR PROPOSED SITE CAPITAL ENTERPRISES I I - 'a ¢¢ DEVELOPMENT AND ULTIMATELY ZONED: C-1 I' ..1 1 _ a w .1`' w COINCIDE WITH THE APPROVED USE: OFFICE BUILDING .I 1''' 1 I -- - - - ¢w n ; > o WALL PLAN BY OTHERS FOR LANDSCAPE PLAN. ------ - 1I 1 _ • - ----- SEE CONSTRUCTION DETAILS. - 1 1 • -- - --' F 41, ' I 0 `a'.o _ ..— `"j 1 WASH RACK ("WR') SHALL BE !� .5.--d' �- I INSTALLED IN ACCORDANCE WITH ii�'�n` - I THE CONSTRUCTION ENTRANCE AND SLOPE TO „'si oy s� ' ' I A TEMPORARY DRAIN PIT SHOWN DOWNGRADIENT __,•. /r c.;- I I OF THE ENTRANCE. CONTRACTOR TO ENSURE NO '.I,>8."'�.♦SF�/ - - r"+ / "" ,0 1 SEDIMENT IS TRACKED ONTO HYDRAULIC ROAD. . - J �•< / �\♦� !- --_ - K."I--='=-- ( ) I ADDITIONAL MEASURES MAY BE REQUIRED AS - - DEEMED NECESSARY BY ALBEMARLE COUNTY / /' ♦��.�, - 1 . .-\-•;%`,.�..;1" I • 1 I EROSION INSPECTOR. ii•-\/-7-.,./..:'.'/./.:",-.71.-.1r1,-(e \ ‘:,_.1 I : I l ....., g \ ,\ - - /y .g. .14.♦•K 1, !\!�-,`'`'\'4\, - ,-,1(_.^.. i,:^ - -- i\/\\ yIlL,r\L I 11 \ 1 11,1 I/ I \ y/ I `! az .'- .II .�'* /��L< - 1 1 •I-li\+\I X-- V • i. _� \ \\ _ - _ I 'I _nr'+:r`'.';'';f�.;e'..v,1,'r\ 1_Al,c'f '��"I I _�'\' 't''• \�'•\/\ ', \. i i i_ �. i / u, L/ �` `\\� — - r ,,\ x �� `'S. .x- -,.1' \,l/,v �//l• ' I IA-• / (j q" i,i{,i\i\i`± / v ./' y \ �, e1 'PLNE�z •? 3';::`i.•� .,�i/ i•\/1\�`J'i i li' Ir,-1\/\/.\/, i - \ \ \ /�`,\ [ f y:.,y.:.s.`'Y' - ,, U;_{'I r._/• ; ,.,%--•,( , ��'•- \I -r�',I /II I' I / . , (�,. 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'1 , I iJ \:\ / _ - �- DESIGNED BY:JLFNSMP) I KIO CHR, 17:1/1'ram�:1-3, \. 3 —. -i i \ Q \ 4 /'' - - DRAWN BY: JLFNVN \ \ ' TMP 60E-2 \� 24"„HRYI }� .i' SILT FENCE .88 1 is 4:< {'' , W� I 1\ 1 \ \ 1 CHECKED BY: JLT �\ \ ` \ ' GEORGETOWN GREEN ? :.li-TO SILT FENCE= 0.88 AC :ir�'j<`, 'ry,w;;'"- '\,� , 1 I1 ==_ --=_ _ _ - - 1.--'-',,,,.‹. \ ZONED: R-6 ;:LINEAL FOOTAGE OF SILT "` - ro / ,�-I IPHASE I GRADING OF EROSION CONTROL PLAN \ - I _ - - _ - _J_ /'C/ \ \ USE: RESIDENTIAL ) \ "te° FENCE=530 LF `' .'✓"�z' `� t;Lq t \\\ COMMON AREA -'':' G�v� • p \\\ I2'POP r"" (DOES NOT EXCEED ''.....s-' - f$ ,�1 `�� t 1� - _ LTA OF t '•\ 0• •r " I \I." ,\I w ` ' I OPERATIONS SHOULD GENERALLY FOLLOW FINAL 6 D 4 \ \ \ / C�� - ALLOWABLE F_':�_�n.;...a..--,,,7, ,Y7 I 1 - \ PROPOSED GRADING WHILE ALLOWING FOR REASONABLE - - - - - - ; �� \ \ \ EX CHAINUNK FENXE 0';,4`-'-'I}0.25 ACRES PER `00 LF-;- p--sq 'ter-' �Y Il \ wp `�g I, I \ CONSTRUCTION MACHINERY ACCESS TO THE PROPOSED - /' \ _ ..;4_, +---.r ;- -"--"'� ' \ RETAINING WALLS" WALL CONSTRUCTION SHOULD BEGIN _ o /�� '. `\ \ - OP 'f'-"=; 4E;;-.� f i, .- 4•p tI 1 \ FIRST IN ORDER TO BRING STRUCTURAL BACKFILL UP TO \ - \\ \\ \ .', y;iT'.. }• 1 ...:s44 ;r Y'�` ztl/�1 A,\ I BENCHMARK FINAL PROPOSED SITE GRADE. SEE WALL DESIGN PLAN ` ,. ?•�. 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PHYSICAL MAILING.E 929 SEUUND SI,SE 435 MERCHANT WALK SO SUITE 300-1 g,' CHARLOI TLSVILLL,VA 22002 , 29 ? ' CHARM./I IESVILLE.VA 22902 N • 9 .-..2 ...,C '.4. A. 04 . 13, EROSION CONTROL PLAN PHASE II .4 vitt 0 PHONE 434477-0205 WVVW.ROUDABUSH.COM co , EROSION AND SEDIMENT CONTROL NARRATIVE RE-SEEDED AS NEEDED TO ESTABLISH GROWTH. PRIOR TO ANY UPSLOPE LAND DISTURBANCE THAT TAKES PLACE. EXTENT POSSIBLE DURING CONSTRUCTION. NON-ERODIBLE MATERIAL V SHALL BE USED FOR THE CONSTRUCTION OF CAUSEWAYS AND .0 PRIOR TO CONSTRUCTION 7. THE JOB SUPERINTENDENT SHALL BE RESPONSIBLE FOR THE 3.1. SILT FENCE SHALL BE INSTALLED ON THE DOWNHILL SIDE OF COFFERDAMS. EARTHEN FILL MAY BE USED FOR THESE STRUCTURES •. y 1. OWNER SHALL POST SURETY BONDS FOR CONSTRUCTION, EROSION & INSTALLATION AND MAINTENANCE OF ALL EROSION AND SEDIMENT THE ACTIVE GRADING OPERATIONS. IF ARMORED BY NON-ERODIBLE COVER MATERIALS.CONTRACTOR SEDIMENT CONTROL. CONTROL PRACTICES. SHALL FOLLOW THE VESCH CHAPTER 3.25 UTILITY STREAM CROSSING U Z z o 2. CONTRACTOR SHALL OBTAIN PERMITS TO WORK WITHIN STATE 4. PRIOR TO ADDITIONAL CLEARING AND GRUBBING, THE CONTRACTOR REQUIREMENTS FOR THE TWO INTERMITTENT STREAM CROSSINGS. O N a a y RIGHT-OF-WAY(VOOT LAND-USE PERMIT). BONDING FOR WORK 8. DURING FINE GRADING OPERATIONS, MAINTAIN ALL DIVERSION SHALL COORDINATE INSPECTIONS, AS REQUIRED BY THE COUNTY OF 13. WHEN A LIVE WATERCOURSE MUST BE CROSSED BY CONSTRUCTION V) Q a' i 3 L g WITHIN THE VDOT RIGHT-OF-WAY MAY BE REQUIRED TO OBTAIN THE DITCHES TO THE SEDIMENT TRAP. THE SEDIMENT TRAP SHALL ALBEMARLE. VEHICLES MORE THAN TWICE IN ANY SIX-MONTH PERIOD, A Q O'. PERMIT. REMAIN FUNCTIONAL THROUGHOUT CONSTRUCTION. TEMPORARY VEHICULAR STREAM CROSSING CONSTRUCTED OF o ' 3. CONTRACTOR SHALL COORDINATE WITH OWNER TO OBTAIN VSMP 5. CLEAR AND GRUB THE REMAINDER OF PROJECT AREA. NON-ERODIBLE MATERIAL SHALL BE PROVIDED.CONTRACTOR SHALL de O m a:g o PERMITS, AS REQUIRED BY THE STATE DEPARTMENT OF AFTER BEING NOTIFIED BY THE EROSION AND SEDIMENT CONTROL FOLLOW THE VESCH CHAPTER 3.25 UTILITY STREAM CROSSING ADMINISTRATOR, THE TEMPORARY EROSION AND SEDIMENT CONTROLS 5.1. THE LAND DISTURBANCE SHALL BE RESTRICTED TO THE LIMITS REQUIREMENTS FOR THE TWO INTERMITTENT STREAM CROSSINGS. W 0< p, ENVIRONMENTAL SQHALL OBTAINB NELA. -,Z e 4. CONTRACTOR SHALL LAND DISTURBANCE PERMIT FROM THE CAN BE CLEANED UP OR REMOVED, AND THE SEDIMENT TRAP CAN BE OF DISTURBANCE SHOWN IN THE APPROVED EROSION CONTROL 14. ALL APPLICABLE FEDERAL, STATE AND LOCAL REQUIREMENTS W <_ COUNTY OF ALBEMARLE PRIOR TO BEGINNING CONSTRUCTION FILLED IN AND SEEDED FOR SITE STABILIZATION. PLANS. PERTAINING TO WORKING IN OR CROSSING LIVE WATERCOURSES <4 ZO> 5. A PRE-CONSTRUCTION MEETING WITH THE ENGINEER, THE CERTIFIED SHALL BE MET.CONTRACTOR SHALL FOLLOW FOLLOW ALL LAND DISTURBER, AND THE ENVIRONMENTAL INSPECTOR MAY ALSO PERMANENT STABILIZATION 5.2. THESE LIMITS ARE CONFINED TO THE PROPERTY BOUNDARIES APPLICABLE FEDERAL, STATE AND LOCAL REQUIREMENTS FOR THE N BE REQUIRED. ALLOW 72 HOURS FOR COORDINATION AND ALL AREAS DISTURBED BY CONSTRUCTION SHALL BE STABILIZED WITH SHOWN HEREON THIS PLAN. TWO INTERMITTENT STREAM CROSSINGS. � el,'Z SCHEDULING OF PRE-CONSTRUCTION MEETING. STRAW&SEED IMMEDIATELY FOLLOWING FINISHED GRADE. SEEDING 15. THE BED AND BANKS OF A WATERCOURSE SHALL BE STABILIZED V] O j 6. AREA OF FOREST/OPEN SPACE SHALL BE DEMARCATED SHALL BE DONE WITH KENTUCKY 31 TALL FESCUE IN ACCORDANCE TO 6. STOCKPILE TOPSOIL WITHIN AN AREA ON THE PROPERTY OR A IMMEDIATELY AFTER WORK IN THE WATERCOURSE IS � a w (FENCED-OFF) PRIOR TO ANY LAND DISTURBING ACTIVITIES. STANDARD AND SPECIFICATION 3.32, PERMANENT SEEDING, OF THE LOCATION APPROVED BY ALBEMARLE COUNTY. INSTALL SILT FENCE COMPLETED.CONTRACTOR SHALL FOLLOW THE VESCH CHAPTER 3.25 - n< VIRGINIA EROSION AND SEDIMENT CONTROL HANDBOOK. ANY FERTILIZER AT THE PERIMETER OF STOCKPILE(S) AS NECESSARY. UTILITY STREAM CROSSING REQUIREMENTS FOR THE TWO < -.7 Z' °° AND LIME APPLICATIONS SHALL BE IN ACCORDANCE WITH SOIL TEST INTERMITTENT STREAM CROSSINGS. PROJECT DESCRIPTION RESULTS. ALL SEEDED AREAS WILL BE STRAW MULCHED TO PROTECT 7. DENUDED AREAS SHALL DRAIN TO AN APPROVED EROSION CONTROL 16. UNDERGROUND UTILITY LINES SHALL BE INSTALLED IN ACCORDANCE n THIS PROJECT PROPOSES TO DEVELOP COMMERCIAL PROPERTY AT THE AGAINST RILL EROSION AND TO PRESERVE SOIL MOISTURE THAT WILL MEASURE AT ALL TIMES DURING CONSTRUCTION. WITH THE FOLLOWING STANDARDS IN ADDITION TO OTHER n INTERSECTION OF GEORGETOWN AND HYDRAULIC ROAD. THIS PROJECT r PROPOSES TO DISTURB A TOTAL OF 0.88 ACRES. ENHANCE SEED GERMINATION. CRIMPING, PUNCH ROLLER-TYPE ROLLERS, APPLICABLE CRITERIA: Q OR TRACK WALKING MAY BE USED TO INCORPORATE STRAW MULCH INTO 8. PERMANENT OR TEMPORARY SOIL STABILIZATION SHALL BE APPUED A. NO MORE THAN 500 LINEAR FEET OF TRENCH MAY BE OPENED AT Qy EXISTING SITE CONDITIONS THE SOIL ON SLOPES IF STRAW IS TO BE USED. TO ALL DENUDED AREAS WITHIN SEVEN DAYS AFTER FINAL GRADE IS ONE TIME. u THE CURRENT CONDITIONS OF THIS LOT CONSISTS OF APPROXIMATELY 1 REACHED ON ANY PORTION OF THE SITE. TEMPORARY SOIL B. EXCAVATED MATERIAL SHALL BE PLACED ON THE UPHILL SIDE OF ACRE OF VACANT, GENTLE TO MODERATELY STEEP SLOPING WOODED EROSION CONTROL MAINTENANCE STABILIZATION SHALL BE APPLIED WITHIN SEVEN DAYS TO DENUDED TRENCHES LAND THAT GENERALLY DRAINS DOWNGRADIENT WEST OF THE PARCEL 1. IN GENERAL, ALL EROSION AND SEDIMENT CONTROL MEASURES AREAS THAT MAY NOT BE AT FINAL GRADE BUT WILL REMAIN C. EFFLUENT FROM DEWATERING OPERATIONS SHALL BE FILTERED OR SHALL BE CHECKED DAILY AND AFTER EACH SIGNIFICANT RAINFALL. DORMANT FOR LONGER THAN 30 DAYS. PERMANENT STABILIZATION PASSED THROUGH AN APPROVED SEDIMENT TRAPPING DEVICE, OR ADJACENT AREAS THE FOLLOWING ITEMS WILL BE CHECKED IN PARTICULAR: SHALL BE APPLIED TO AREAS THAT ARE TO BE LEFT DORMANT FOR BOTH, AND DISCHARGED IN A MANNER THAT DOES NOT ADVERSELY THE LOT IS BOUND BY A MIX OF COMMERCIAL AND RESIDENTIAL MORE THAN ONE YEAR. AFFECT FLOWING STREAMS OR OFF-SITE PROPERTY. PROPERTIES THAT RUN ALONG PUBLIC RIGHT OF WAY. 2. THE CONSTRUCTION ENTRANCE SHALL BE CHECKED DAILY FOR SOIL D. MATERIAL USED FOR BACKFILLING TRENCHES SHALL BE PROPERLY BUILDUP. IF THE ENTRANCE BECOMES CLOGGED WITH SOIL AND FAILS 9. LIME, FERTILIZE AND APPLY TEMPORARY OR PERMANENT SEEDING TO COMPACTED IN ORDER TO MINIMIZE EROSION AND PROMOTE OFF-SITE AREAS TO PREVENT THE TRANSPORTATION OF SOIL ONTO THE ROADWAY, ALL DENUDED AREAS IMMEDIATELY AFTER ACHIEVING FINAL GRADES. STABILIZATION. ANY EXCESS MATERIAL GENERATED AS PART OF THIS PROJECT SHALL BE ADDITIONAL STONE, REPLACEMENT OF STONE, OR A WASH-RACK E. RE-STABILIZATION SHALL BE ACCOMPLISHED IN ACCORDANCE WITH o STORED OR SPREAD WITHIN THE APPROVED LAND DISTURBANCE AREA OR MAY BE REQUIRED. 10. ALL PERMANENT SLOPES STEEPER THAN 3:1 SHALL RECEIVE THIS CHAPTER.IN AN AREA APPROVED BY THE COUNTY OF ALBEMARLE. STABILIZATION WITH LANDSCAPING VEGETATION HARDIER THAN F. APPLICABLE SAFETY REQUIREMENTS SHALL BE COMPLIED _ 3. SILT FENCE SHALL BE INSPECTED IMMEDIATELY AFTER EACH GRASS, WHICH WILL NOT REQUIRE MOWING. WITH.CONTRACTOR TO ADHERE TO THE APPLICABLE STANDARD FOR . o RAINFALL AND AT LEAST DAILY DURING PROLONGED RAINFALL PRIVATE AND PUBLIC UTILITY INSTALLATION. SOILS SOILS COLET SANDY LOAM - 2 TO 7 PERCENT SLOPES CLOSE ATTENTION SHALL BE PAID TO THE REPAIR OF DAMAGED SILT 11. AFTER PROPOSED CONSTRUCTION IS COMPLETED AND THE SITE IS 17. WHERE CONSTRUCTION VEHICLE ACCESS ROUTES INTERSECT PAVED HYDROLOGIC SOIL GROUP B. DEEP, WELL-DRAINED SOIL. MEDIUM CLASS FENCE RESULTING FROM END RUNS AND UNDERCUTTING. SHOULD COMPLETELY STABILIZED, PERMISSION IS TO BE OBTAINED FROM THE OR PUBLIC ROADS, PROVISIONS SHALL BE MADE TO MINIMIZE THE RUNOFF WITH LAYERS CONSISTING OF SANDY LOAM, CLAY, AND SANDY THE FABRIC ON A SILT FENCE DECOMPOSE OR BECOME INEFFECTIVE EROSION CONTROL INSPECTOR FOR THE REMOVAL OF SILT FENCING TRANSPORT OF SEDIMENT BY VEHICULAR TRACKING ONTO THE PAVED CLAY LOAM. LOW FREQUENCY OF FLOODING AND PONDING WITH MODERATE PRIOR TO THE END OF THE EXPECTED USABLE LIFE AND THE AND OTHER REMAINING TEMPORARY EROSION CONTROL MEASURES. SURFACE. WHERE SEDIMENT IS TRANSPORTED ONTO A PAVED OR EROSION. BARRIER STILL BE NECESSARY, THE FABRIC SHALL BE REPLACED PUBLIC ROAD SURFACE, THE ROAD SURFACE SHALL BE CLEANED "' PROMPTLY. SEDIMENT DEPOSITS SHOULD BE REMOVED AFTER EACH EROSION AND SEDIMENT CONTROL MINIMUM STANDARDS THOROUGHLY AT THE END OF EACH DAY. SEDIMENT SHALL BE o CRITICAL AREAS STORM EVENT. THEY MUST BE REMOVED WHEN DEPOSITS REACH 1. PERMANENT OR TEMPORARY SOIL STABILIZATION SHALL BE APPLIED REMOVED FROM THE ROADS BY SHOVELING OR SWEEPING AND h CRITICAL AREAS WITHIN THE DEVELOPMENT INCLUDE THE APPROXIMATELY ONE-HALF THE HEIGHT OF THE BARRIER. ANY TO DENUDED AREAS WITHIN SEVEN DAYS AFTER FINAL GRADE IS TRANSPORTED TO A SEDIMENT CONTROL DISPOSAL AREA. STREET SEDIMENT DEPOSITS REMAINING IN PLACE AFTER THE SILT FENCE IS REACHED ON ANY PORTION OF THE SITE. TEMPORARY SOIL WASHING SHALL BE ALLOWED ONLY AFTER SEDIMENT IS REMOVED IN O z CRITICAL SLOPES THAT RUN CENTRALIZED THROUGH THE NO LONGER REQUIRED SHALL BE DRESSED TO CONFORM WITH THE STABILIZATION SHALL BE APPLIED WITHIN SEVEN DAYS TO DENUDED THIS MANNER. THIS PROVISION SHALL APPLY TO INDIVIDUAL PARCEL. EXTREME CAUTION SHALL BE USED WHEN GRADING EXISTING GRADE, PREPARED, AND SEEDED. AREAS THAT MAY NOT BE AT FINAL GRADE BUT WILL REMAIN DEVELOPMENT LOTS AS WELL AS TO LARGER LAND-DISTURBING THESEOICRITICAL AREAS TO AVOID EXCESSIVE DOWNSTREAM DORMANT FOR LONGER THAN 14 DAYS. PERMANENT STABILIZATION ACTIVITIES.CONTRACTOR SHALL MAKE PROVISIONS TO KEEP - EROSION. 4. DIVERSION DIKES SHALL BE INSPECTED AFTER EVERY STORM AND SHALL BE APPLIED TO AREAS THAT ARE TO BE LEFT DORMANT FOR ADJACENT ROADS CLEAN FROM SOIL BUILD-UP. z z STRUCTURAL PRACTICES REPAIRS MADE TO THE DIKE, FLOW CHANNEL, OUTLET, OR SEDIMENT MORE THAN ONE YEAR. 18. ALL TEMPORARY EROSION AND SEDIMENT CONTROL MEASURES SHALL 1. TEMPORARY CONSTRUCTION (3.02) -A TRAPPING FACILITY AS NECESSARY. ONCE EVERY TWO WEEKS, CONTRACTOR SHALL ESTABLISH A STABILIZED SITE, AND NOT ALLOW ANY BE REMOVED WITHIN 30 DAYS AFTER FINAL SITE STABILIZATION OR o 0 0 Y ENTRANCE SHALLENTRANCE INSTALLED AT TEMPORARYE ENTRANCE WHETHER A STORM EVENT HAS OCCURRED OR NOT, THE MEASURE SEDIMENT TO EXIT THE PROJECT LIMITS. AFTER THE TEMPORARY MEASURES ARE NO LONGER NEEDED, OFF OF CONSTRUCTIONNY LANETR ROAD. SHALL BE INSPECTED AND REPAIRS MADE IF NEEDED. DAMAGES 2. DURING CONSTRUCTION OF THE PROJECT, SOIL STOCKPILES AND UNLESS OTHERWISE AUTHORIZED BY THE VESCP AUTHORITY. z z CAUSED BY CONSTRUCTION TRAFFIC OR OTHER ACTIVITY MUST BE BORROW AREAS SHALL BE STABILIZED OR PROTECTED WITH TRAPPED SEDIMENT AND THE DISTURBED SOIL AREAS RESULTING REPAIRED BEFORE THE END OF EACH WORKING DAY. SEDIMENT TRAPPING MEASURES. THE APPLICANT IS RESPONSIBLE FROM THE DISPOSITION OF TEMPORARY MEASURES SHALL BE a o o B B 2. ROAD STABILIZATION (3.03) - ACCESS ROADS,PARKING AREAS, AND FOR THE TEMPORARY PROTECTION AND PERMANENT STABILIZATION PERMANENTLY STABILIZED TO PREVENT FURTHER EROSION AND OTHER ON-SITE VEHICLE TRANSPORTATION ROUTES SHALL BE 5. STORMWATER CONVEYANCE CHANNELS(WHERE APPLICABLE): OF ALL SOIL STOCKPILES ON SITE AS WELL AS BORROW AREAS AND SEDIMENTATION.CONTRACTOR SHALL STABILIZE SITE, AND OBTAIN STABILIZED WITH STONE IMMEDIATELY AFTER GRADING. 5.1. GRASS LINED CHANNELS- DURING THE INITIAL ESTABLISHMENT, SOIL INTENTIONALLY TRANSPORTED FROM THE PROJECT SITE. INSPECTOR APPROVAL PRIOR TO REMOVING EC MEASURES. UPON GRASS LINED CHANNELS SHOULD BE REPAIRED IMMEDIATELY CONTRACTOR TO PROTECT STOCKPILE AREAS WITH SILT FENCE. APPROVAL OF THE ENVIRONMENTAL INSPECTOR, INSTALL "' ,��., 3. WIT FENCE BARRIER (3 05) - SILT FENCE BARRIERS WILL BE AND RE-ESTABLISHED IF NECESSARY. AFTER GRASS HAS 3. A PERMANENT VEGETATIVE COVER SHALL BE ESTABLISHED ON INFILTRATION AREAS AND CONNECT ROOF DRAINS. o o r INSTALLED TO FILTER RUNOFF FROM SHEET FLOW AS INDICATED ON BECOME ESTABLISHED, THE CHANNEL SHOULD BE CHECKED DENUDED AREAS NOT OTHERWISE PERMANENTLY STABILIZED. 19. PROPERTIES AND WATERWAYS DOWNSTREAM FROM DEVELOPMENT �.,m THE EROSION AND SEDIMENT CONTROL PLAN. PERIODICALLY TO DETERMINE IF THE GRASS IS WITHSTANDING PERMANENT VEGETATION SHALL NOT BE CONSIDERED ESTABLISHED SITES SHALL BE PROTECTED FROM SEDIMENT DEPOSITION, EROSION FLOW VELOCITIES WITHOUT DAMAGE. IF THE CHANNEL IS TO BE UNTIL A GROUND COVER IS ACHIEVED THAT IS UNIFORM, MATURE AND DAMAGE DUE TO INCREASES IN VOLUME, VELOCITY AND PEAK z"^' MOWED, IT SHOULD BE DONE IN A MANNER THAT IT WILL NOT ENOUGH TO SURVIVE AND WILL INHIBIT EROSION. FLOW RATE OF STORMWATER RUNOFF FOR THE STATED FREQUENCY VEGETATIVE PRACTICES DAMAGE THE GRASS. CONTRACTOR SHALL ESTABLISH A VEGETATIVE COVER ON ALL DENUDED STORM OF 24-HOUR DURATION IN ACCORDANCE WITH THE 1. SURFACE ROUGHENING(3.29) - ALL AREAS WITH A GRADE STEEPER 5.2. RIPRAP-LINED CHANNELS- RIPRAP LINED CHANNELS SHOULD AREAS. FOLLOWING STANDARDS AND CRITERIA. STREAM RESTORATION AND DESIGNED BY-JLF(VSMP) THAN 3:1 SHALL BE STAIR-STEP GRADED OR GROOVED (PLATE BE CHECKED PERIODICALLY TO ENSURE THE SCOUR IS NOT 4. SEDIMENT BASINS AND TRAPS. PERIMETER DIKES, SEDIMENT RELOCATION PROJECTS THAT INCORPORATE NATURAL CHANNEL DRAWN BY: JLFPJVN 3,29-4) TO AID IN GRASS ESTABLISHMENT, INCREASE INFILTRATION;' OCCURRING BENEATH FABRIC UNDERLINING OF THE RIPRAP BARRIERS AND OTHER MEASURES INTENDED TO TRAP SEDIMENT DESIGN CONCEPTS ARE NOT MAN-MADE CHANNELS AND SHALL BE CHECKED BY JLT AND TO SLOW RUNOFF VELOCITIES. LAYER. THE CHANNEL SHOULD ALSO BE CHECKED TO SHALL BE CONSTRUCTED AS A FIRST STEP IN ANY EXEMPT FROM ANY FLOW RATE CAPACITY AND VELOCITY DETERMINE THE STONES ARE NOT DISLODGED BY LARGE LAND-DISTURBING ACTIVITY AND SHALL BE MADE FUNCTIONAL REQUIREMENTS FOR NATURAL OR MAN-MADE CHANNELS:THIS 2. TOPSOIUNG &STOCKPILING(3.30) - TOPSOIL WILL BE STRIPPED FLOWS. BEFORE UPSLOPE LAND DISTURBANCE TAKES PLACE. PROJECT DOES NOT INCLUDE ANY ADDITIONAL IMPERVIOUS SURFACES 4,0,TH Op` FROM AREAS TO BE GRADED AND STOCKPILED FOR LATER USE. 5.3. IF SEDIMENT IS DEPOSITED IN A GRASS-LINED CHANNEL IT CONTRACTOR SHALL ESTABLISH THE PERIMETER CONTROLS OF SUPER SILT AND THE PROJECT AREA WILL BE RESTORED TO ITS EXISTING ... 4,, STOCKPILES ARE TO BE STABILIZED WITH TEMPORARY VEGETATION SHOULD BE REMOVED PROMPTLY TO PREVENT DAMAGE TO THE FENCE AS THE FIRST STEP OF THE LANDS DISTURBANCE FOR THIS CONIDTIONS.THEREFORE WILL NOT PRODUCE ANY ADDITIONAL y OR TO HAVE SILT FENCE INSTALLED ALONG THE LOWER PERIMETER GRASS. SEDIMENT DEPOSITED IN A RIPRAP CHANNEL SHOULD PROJECT. STORMWATER RUNOFF. .o . 7. TO PROTECT DOWNSTREAM AREAS. BE REMOVED WHEN IT REDUCES THE CAPACITY OF THE 5. STABILIZATION MEASURES SHALL BE APPLIED TO EARTHEN A. CONCENTRATED STORMWATER RUNOFF LEAVING A DEVELOPMENT SITE CHANNEL. STRUCTURES SUCH AS DAMS, DIKES AND DIVERSIONS IMMEDIATELY SHALL BE DISCHARGED DIRECTLY INTO AN ADEQUATE NATURAL OR 3. TEMPORARY SEEDING (3.31) - AREAS NOT BROUGHT TO FINAL AFTER INSTALLATION. MAN-MADE RECEIVING CHANNEL, PIPE OR STORM SEWER SYSTEM. FOR Jimmy L.Taggart GRADE FOR A PERIOD OF MORE THAN 14 DAYS SHALL BE 6. CHECK DAMS(WHERE APPLICABLE): SHALL BE CHECKED FOR CONTRACTOR SHALL INSPECT EROSION CONTROL MEASURES AFTER EACH THOSE SITES WHERE RUNOFF IS DISCHARGED INTO A PIPE OR PIPE uc.No. -,. STABILIZED WITH A TEMPORARY SEEDNMIXTURELL ACCEPTABLETYPRO FOR SEDIMENT ACCUMULATION AFTER EVERY RUNOFF PRODUCING STORM RAINFALL EVENT. SYSTEM, DOWNSTREAM STABILITY ANALYSES AT THE OUTFALL OF THE 22861 THAT TIME OF YEAR. CRIMPING, PUNCH ROLLER-TYPE ROLLERS, OR EVENT. SEDIMENT SHOULD BE REMOVED WHEN IT REACHES 6. SEDIMENT TRAPS AND SEDIMENT BASINS SHALL BE DESIGNED AND PIPE OR PIPE SYSTEM SHALL BE PERFORMED. • p`•SS+oxA1.e'O{ TRACK WALKING MAY BE USED TO INCORPORATE STRAW MULCH ONE-HALF OF THE ORIGINAL HEIGHT OF THE MEASURE. REGULAR CONSTRUCTED BASED UPON THE TOTAL DRAINAGE AREA TO BE B. ADEQUACY OF ALL CHANNELS AND PIPES SHALL BE VERIFIED USING INTO THE SOIL ON SLOPES IF STRAW IS TO BE USED. INSPECTIONS SHALL BE MADE TO INSURE THE CENTER OF EACH DAM SERVED BY THE TRAP OR BASIN. THE VSMP CHANNEL PROTECTION CRITERIA. STORMWATER DISCHARGES IS LOWER THAN THE EDGES. EROSION CAUSED BY HIGH FLOWS THERE IS ONE PROPOSED SEDIMENT BASIN ARE CLASSIFIED INTO ONE OF THREE TYPES OF CHANNEL. 4. PERMANENT SEEDING(3.32) - AREAS BROUGHT TO FINAL GRADE OR AROUND THE EDGES OF THE DAM SHOULD BE CORRECTED A. THE MINIMUM STORAGE CAPACITY OF A SEDIMENT TRAP SHALL BE (1) "MANMADE STORMWATER CONVEYANCE SYSTEM" MEANS A THOSE CONSTRUCTION AREAS THAT WILL REMAIN DORMANT FOR IMMEDIATELY. 134 CUBIC YARDS PER ACRE OF DRAINAGE AREA AND THE TRAP PIPE, DITCH, VEGETATED SWALE, OR OTHER STORMWATER Z YEAR OR MORE SHALL BE STABILIZED WITH A PERMANENT SEED SHALL ONLY CONTROL DRAINAGE AREAS LESS THAN THREE ACRES. CONVEYANCE SYSTEM CONSTRUCTED BY MAN EXCEPT FOR z MIXTURE ACCEPTABLE TO THAT TIME OF YEAR.PREPARE SURFACE 7• THE EARTHEN EMBANKMENTS SHALL BE CHECKED REGULARLY TO B. SURFACE RUNOFF FROM DISTURBED AREAS THAT IS COMPRISED OF RESTORED STORMWATER CONVEYANCE SYSTEMS OR, WITH APPROVED TREATMENT AND ADDITIVES PRIOR TO APPLYING ENSURE THAT IT IS STRUCTURALLY SOUND AND HAS NOT BEEN FLOW FROM DRAINAGE AREAS GREATER THAN OR EQUAL TO THREE (A)THE MANMADE STORMWATER CONVEYANCE SYSTEM SHALL EL U SEED. DAMAGED BY EROSION OR CONSTRUCTION EQUIPMENT. ACRES SHALL BE CONTROLLED BY A SEDIMENT BASIN. THE MINIMUM CONVEY THE POST-DEVELOPMENT PEAK FLOW RATE FROM , STORAGE CAPACITY OF A SEDIMENT BASIN SHALL BE 134 CUBIC THE TWO-YEAR EVENT WITHOUT CAUSING EROSION OF THE Z J 5. MULCH (3.35) - PLANT RESIDUES OR OTHER SUITABLE MATERIALS 8. THE STORMWATER MANAGEMENT FACILITIES SHOULD BE CHECKED YARDS PER ACRE OF DRAINAGE AREA. THE OUTFALL SYSTEM SHALL, SYSTEM DETENTION OF THE STORMWATER OR DOWNSTREAM LLI D LU SHALL APPLIED TON DISTURBED SURFACESTHIS PREVENT EROSION REGULARLY BY THE HOMEOWNERS ASSOCIATIONS TO ENSURE THAT AT A MINIMUM. MAINTAIN THE STRUCTURAL INTEGRITY OF THE BASIN IMPROVEMENTS MAY BE INCORPORATED INTO THE APPROVED THEY ARE STRUCTURALLY SOUND AND HAVE NOT BEEN DAMAGED DURING A 25-YEAR STORM OF 24-HOUR DURATION. RUNOFF LAND-DISTURBING ACTIVITY TO MEET THIS CRITERIA AT THE Q AND REDUCE OVERLAND SEEDINGN VELOCITIES.RATIO OTHER PRACTICELANTESHOULD COEFFICIENTS USED IN RUNOFF CALCULATIONS SHALL CORRESPOND TO DISCRETION OF THE STORMWATER PROGRAM ADMINISTRATIVE W = BE APPLIED TO ALL OPERATIONS, PLANTER BY EROSION. 0 CC A BARE EARTH CONDITION OR THOSE CONDITIONS EXPECTED TO EXIST AUTHORITY. z Q THEMSELVES, , H NOT PRO H ADEQUATE O SOIL E EDPROTECTION BY 9. THE EMERGENCY SPILLWAY SHALL BE CHECKED REGULARLY TO WHILE THE SEDIMENT BASIN IS UTILIZED. (B)THE PEAK DISCHARGE REQUIREMENTS FOR CONCENTRATED < r7 2 THE S EASON, ANDBAREWHICH AREAS WHICH PROTECTIONC BE SEEDED DUE SOILL ENSURE THAT ITS LINING IS WELL ESTABLISHED AND EROSION 7. CUT AND FILL SLOPES SHALL BE DESIGNED AND CONSTRUCTED IN A STORMWATER FLOW TO NATURAL STORMWATER CONVEYANCE Z > Q THE SEASON BUT STILL NEED ROLLE TO PREVENT RESISTANT. GRASS SHALL BE KEPT MOWN BELOW A HEIGHT OF 15'. MANNER THAT WILL MINIMIZE EROSION. SLOPES THAT ARE FOUND TO SYSTEMS SHALL BE MET. Q = J Z WALKING CRIMPING,E PUNCHEDINCORPORATECRO ROLLERS, OR TRACK AND THE OUTLET SHOULD BE CHECKED FOR CLOGGING. BE ERODING EXCESSIVELY WITHIN ONE YEAR OF PERMANENT QDEVELOPED <= I.F. •(QPRE-DEV. • RVPRE-DEV.) / 2 s J WALKING MAY BE USED TO STRAW MULCH INTO THE STABILIZATION SHALL BE PROVIDED WITH ADDITIONAL SLOPE RVDEVELOPED 1.1T Tp Q z SOIL ON SLOPES IF STRAW IS TO BE USED. 10. THE DAM SECTION SHALL BE KEPT FREE OF SAPLINGS OR STABILIZING MEASURES UNTIL THE PROBLEM IS CORRECTED. THERE UNDER NO CONDITION SHALL QDEVELOPED >0 PRE-DEV. EROSION&SEDIMEN 1 CON ROL LEGEND w m F_ ARE NO PROPOSED CUT OR FILL SLOPES. HOWEVER, THE TREES.(REFER TO THE ADDITIONAL MAINTENANCE SPECIFICATIONS) NOR SHALL QDEVELOPED BE REQUIRED TO BE LESS THAN f a Z 6. DUST CONTROL(3.391 - DUST CONTROL METHODS MUST BE USED CONTRACTOR IS TO RESTORE THE PROJECT AREA TO EXISTING TO REDUCE THE AMOUNT OF AIRBORNE DUST DURING ALL PHASES 11. ALL SEEDED AREAS WILL BE CHECKED REGULARLY TO ENSURE THAT GRADE. IF THE AREAS WITH NATURALLY STEEP SLOPES ARE FOUND THAT OREST•RVPRE-DEV.)/RVDEVELOPED P C E 3.02 PAVED CONSTRUCTION V O OF CONSTRUCTION WHERE SOIL IS EXPOSED OR DISTURBED. A GOOD STAND IS MAINTAINED. AREAS SHOULD BE FERTILIZED AND TO BE ERODING EXCESSIVELY AFTER ONE YEAR, CONTRACTOR IS TO OR IN ACCORDANCE WITH ANOTHER METHODOLOGY THAT IS /- ENTRANCE H z Z RE-SEEDED AS NEEDED. IN THE EVENT THAT THE APPLIED SEEDING PROVIDE ADDITIONAL SLOPE STABILIZING MEASURES UNTIL THE DEMONSTRATED BY THE VSMP AUTHORITY TO ACHIEVE w p O MANAGEMENT STRATEGIES FAILS TO TAKE HOLD, BLANKET MATTING SHALL BE PLACED IN PROBLEM IS CORRECTED. EQUIVALENT RESULTS AND IS APPROVED BY THE BOARD. SF 3.05 SILT FENCE0 (n CC 1. CONSTRUCTION WILL BE SEQUENCED SO THAT GRADING OPERATIONS 8. CONCENTRATED RUNOFF SHALL NOT FLOW DOWN CUT OR FILL X X X p CD CAN BEGIN AND END AS QUICKLY AS POSSIBLE. APPROPRIATE AREAS DEEMED NECESSARY BY THE ENGINEER OR SLOPES UNLESS CONTAINED WITHIN AN ADEQUATE TEMPORARY OR (2) "NATURAL STORMWATER CONVEYANCE SYSTEM"MEANS THE 0 EROSION CONTROL INSPECTOR. MAIN CHANNEL OF A NATURAL STREAM AND THE 2. THE CONSTRUCTION ENTRANCE AND PERIMETER EROSION CONTROL PERMANENT CHANNEL, FLUME OR SLOPE DRAIN STRUCTURE.MAXIMIZE O (./) UJ MEASURES SUCH AS TREE PROTECTION AND SILT FENCE SHALL BE SEQUENCE OF CONSTRUCTION SHEETFLOW AND GROUNDWATER INFILTRATION FLOOD-PRONE AREA ADJACENT TO THE MAIN CHANNEL OR, QP 3,18 1•�i�1��T`��� OUTLET PROTECTION Q i. AFTER OBTAINING ALL REQUIRED PERMITS THE CONTRACTOR SHALL 9. WHENEVER WATER SEEPS FROM A SLOPE FACE, ADEQUATE DRAINAGE (3) "RESTORED STORMWATER CONVEYANCE SYSTEM" MEANS A INSTALLED AS THE FIRST STEP OF DISTURBANCE. COORDINATE A PRE-CONSTRUCTION MEETING, ALLOWING 72 HOURS OR OTHER PROTECTION SHALL BE PROVIDED.CONTRACTOR TO NOTIFY STORMWATER CONVEYANCE SYSTEM THAT HAS BEEN DESIGNED _ ENGINEER AND COUNTY EROSION CONTROL INSPECTOR. AND CONSTRUCTED USING NEARER CHANNEL DESIGN CD 3. SEDIMENT BASIN MEASURES SHALL BE INSTALLED WITH PERIMETER FOR ITS COORDINATION. TS 3.31 TS TEMPORARY SEEDING CD 10. ALL STORM SEWER INLETS THAT ARE MADE OPERABLE DURING CONCEPTS. RESTORED STORMWATER CONVEYANCE SYSTEMS SILT FENCE PRIOR TO ANY GRADING AND SHALL BE SEEDED AND CONSTRUCTION SHALL BE PROTECTED SO THAT SEDIMENT-LADEN INCLUDE THE MAIN CHANNEL AND THE FLOOD-PRONE AREA CD MULCHED IMMEDIATELY FOLLOWING INSTALLATION. 2. INSTALL CONSTRUCTION ENTRANCE OFF OF MIDWAY LANE ROAD. WATER CANNOT ENTER THE CONVEYANCE SYSTEM WITHOUT FIRST ADJACENT TO THE MAIN CHANNEL. I 2.1. SHOULD THE TEMPORARY CONSTRUCTION ENTRANCE OFF OF BEING FILTERED OR OTHERWISE TREATED TO REMOVE (A)THE DEVELOPMENT SHALL BE CONSISTENT, IN COMBINATION PS 3.32 0 PERMANENT SEEDING 4. THE SEDIMENT BASIN SHALL BE CHECKED FOR SEDIMENT MIDWAY LANE ROAD NOT BE MAINTAINED PROPERLY OR AN SEDIMENT.THERE ARE NO STORM SEWER INLETS PROPOSED. WITH OTHER STORMWATER RUNOFF, WITH THE DESIGN ACCUMULATION AFTER EVERY RUNOFF PRODUCING STORM EVENT. EXCESSIVE AMOUNT OF SOIL FOUND TRACKED ONTO THE PUBLIC THEDESIGN11. BEFORE NEWLY CONSTRUCTED STORMWATER CONVEYANCE CHANNELS PARAMETERS OF THE RESTORED STORMWATER CONVEYANCE • -- SEDIMENT SHOULD BE REMOVED WHEN IT REACHES ONE-HALF OF ROADWAY, THEN A PAVED CONSTRUCTION ENTRANCE, WATER OR PIPES ARE MADE OPERATIONAL, ADEQUATE OUTLET PROTECTION SYSTEM THAT IS FUNCTIONING IN ACCORDANCE WITH THE 03.38 TP Tr TREE PROTECTION DATE- OCTOBER25 2019 THE VOLUME OF THE WET STORAGE. AND ANY REQUIRED TEMPORARY OR PERMANENT CHANNEL LINING DESIGN OBJECTIVES. N/A TANKER TRUCK WITH TWO(2) PRESSURE WASHERS AND A SHALL BE INSTALLED IN BOTH THE CONVEYANCE CHANNEL AND (B)THE PEAK DISCHARGE REQUIREMENTS FOR CONCENTRATED JOB LE OTH 5. TEMPORARY SEEDING OR OTHER STABILIZATION METHODS, SUCH AS SETTLING AREA MAY BE REQUIRED BY THE EROSION AND RECEIVING CHANNEL.THERE ARE NO STORMWATER CONVEYANCE STORM WATER FLOW TO NATURAL STORM WATER CONVEYANCE BASE AGGREGATE WILL FOLLOW IMMEDIATELY AFTER REACHING FINAL SEDIMENT CONTROL PROGRAM ADMINISTRATOR. CHANNELS OR PIPES PROPOSED. SYSTEMS SHALL BE MET. SEE 19(B)(1)(B). C 3.39CD DUST CONTROL FILE 190125 GRADES. 12. WHEN WORK IN A LIVE WATERCOURSE IS PERFORMED, PRECAUTIONS 3. CLEARING AND GRUBBING SHALL FIRST BE LIMITED TO THAT SHALL BE TAKEN TO MINIMIZE ENCROACHMENT, CONTROL SEDIMENT 6. ALL SEEDED AREAS WILL BE CHECKED REGULARLY TO ENSURE THAT NECESSARY TO INSTALL SILT FENCE AND OTHER PERIMETER TRANSPORT AND STABILIZE THE WORK AREA TO THE GREATEST A rnnn CTAAin is.AINTArr.1ED ALE',cuniiLn o€.OEFnOZEB AND CDNTR(IIS All PERIMFTFR CINTRDIS MIIST RF MADE FI IPICTI(1NC1 SHEET OF 9 . 11 / sF SILT FENCE IP INLET PROTECTION cE PAVED CONSTRUCTION ENTRANCE 1CD OUTLET PROTECTION \ u l'ori BLOCK AND GRAVEL DROP INLET PIPE OUTLET CONDITIONS (WITHOUT WIRE SUPPORT) STONE - 70'MIN. -j j c SEDIMENT FILTER CONSTRUCTION A . A z =o-. g 1.SEC THE STAKES. In 2.EXCAVATE A 4'X 4•TRENCH ACCESS 3'SY-2A ASPHALT TOP _ �;y O m - UPSLOPE ALONG THE LINE OF 29 COURSE -R EXISTING ���� Q m 2 3'n Fsi STAKES. PAVEUE T Vet:T�.•-� l In S - a 6 MA%I q WIRE SCREEN CONCRETE BLOCK - ,� ..w: .,.. , •�,/. : Q a I� tr1' �� 6•RUIN.2TA AGGREGATE BASE do I, 1/-IMA '�wiLk:�• p i I / as. `, �/ do �:�.�; � W O¢ Po I)) _I .�� 4 T ®E,'j;�- PROFILE MIMI`���/��r�s!.It PIPE 0T717ET TO FLAT z aU, J �}:y/��/:: ,I 1 I`..:laf\R i\,-J I11..��� AREA W77'II NO OF.FTNED Q- i /ice. III ��� �.a i. h vts: \.4 2.4 1-1 C p ///���%� // ri 161 >� �n®t ��iiii++ PLAN VIEW �:f'1��• HANNEL FLOW . , ' i -��I Ili V : 's f)M1•1 STONE 76'M'N. ��.,1�. ►Iy UJ I, f F)1\4 CONSTRUCTION ASPHALT PAVED �l I:WO%ir:.�lilir Vtakni l a�. ACCESS r'MASHRA(.x L B ,,� a Q -, 'Y�����✓:�r��lr��, �v��jJ�� /^ ti�'ii r Y�r' PAVEMENT' oX ^� QN n: O 3.STAPLE FILTER MATERIAL 4.BACKFILL AND COMPACT 4�tirtgif���1r71�N12•lnfl/r.1 '�T:S�}f.•1Yr1 EXISGQI o' TO STAKES AND EXTEND THE EXCAVATED SOIL ��0'[�J.10616.4.•11���.f1Vr�* 1 f1.Z►�4el ICI- � IT INTO THE TRENCH '�ra�J4�'arr� ��.�!rr: T �1,y,ri'`R =n 9 4 ` ' r� iN:a=.I. Ur% SECTION A-A FLT3R CIOTH KEY Da 6•-9•,REC011DO6n0ED FOR ENTIRE PERMErme 0N T • Vd Res ( }fx GRAVEL OILIER WIRE SCREEN MIST EXTEND FULL WIDTHLo I-. -POSIT,VE ORANAGE W m - 1 Y / /. '� - / OF INGRESS AND EGRESS l TO SE]i IYEM A .I a L 't *h OPERATION 1 TRAPPING DEVICE *..1 •.-,� 1 , rtj `3 / FlLTEPEO WATER �_ I ,O 1 �_ 1 _ ISTets •it01'.11re 1 3d 4 r_ III, III. oVERFLOY PLAN i."'.VEY110�4 A D(MIN.) / .>. T�' RUNOFF �' 1�1 ..�*fir.Ii���.4 -IIIII„`- / I IIII WATER R ,+. -�=1I \ d- ` :Over :ems. t -. SEDIMEM ��`L� f�y��t - 12'MIN. !POSITIVE DRAINAGE ` � f��i�li�l��f�f.• W-1 I-i �� >!�11 TO SEDIMENT V �\e�f\iia..14i PIPE OUTLET TO WELL III-"' =III I' IIIIO .roil_ 2_ -� 11 SHEET FLOW INSTALLATION IIIII 1. � IIIIII-IIIIII GW1f5&IF '\4 X- TRAPPING.-D \�; :•:okaV 1��, DEFINED CHANNEL Z (PERSPECTIVE VIEW) .' ,LOJ�r 1_ •'%•� •• •"• NJ4trC PLAN VIEW �T�,tt� I 1. • II' FILTER CLOT-' L a. 1 SEDIMENT SECTION A-A O 1 SPECIFIC APPLICATION ' o z-• FLOW.- 1.4 -/.:Flow A minimum inter lap of 1 inch umst be installed nit!'a mina'n mn 1 inch baked: d A !�(E`. I THIS METHOD OF INLET PROTECTION IS APPLICABLE WHERE shutoff Take xiaI -� ' i SILT FENCE I p supplying a Nash hose nth a diameter away of 1.5 inches for adequate r�lIIIII� I e .r I HEAVY FLOWS ARE EXPECTED AND WHERE AN OVERFLOW constant pressure.Wash nata mast be earned from the entrance to an SECTION A-A u + I I • • • JJJ ix:' CAPACITY IS NECESSARY TO PREVENT EXCESSIVE PONDING approved settling area to ratios a sedimau.All sediment stall be prevented from F°'�aDTM �'IN*•-e'; oIOmND®FOR MIRE PEROmerER O t 9�1 .e:: :1 A AROUND THE STRUCTURE. entail$storm drains,dicheu Or Rater omrm. NOT S:1.APRON LINING NAY BE 1EPB AP,GROUTED R=RAP,GARTON d1.4 bE"ill. •Y r T T�T AROUND BASKET, CONCRETE. 2.In IS THE LENGTHOR OF THE RB'RAP APRON AS CALCULATED fA ,t ya "` • • • •. 3 y'`{* -'I •GRAVEL SHALL BE VDOT 3, #357 OR#5 COARSE AGGREGATE. PAVED WASH RACK USING PTIRES 3.18-3 AND a rR-9. .7+o III- :• r r• I i`" f 3.G=1.5 TIRES ME KAM M STONE DIamTER,BUT NOT O Z .Y T T_ SO SCALE IFSS THAN 9 INCHES. OOB -111-111-III=_ _• 11-111-111- • Source:Va.DSWC Plate 3.18-1 -1 I H I I-1 I I-1 11I 1 EI I 1-I 11E I I- SOURCE:VA.DSWC PLATE. 3.07-3 c 1 1=111=11 I-1 I Iaj 1=111 I I' i p =11 I-1 11=111-11 I- z n L SF/STONE NOT REQUIRED AFTER SLOPES ARE STABILIZED DOWNSLOPE OF OUTFACE TEMPORARY SEEDING MIXTURES PERMANENT SEEDING MIXTURES PERMANENT SEEDING a 8 3 POINTS A SHOULD BE HIGHER THAN POINT B. TS FOR THE PIEDMONT AREA Ps FOR THE PIEDMONT AREA Ps DRAINAGEWAY INSTALLATION FERTILIZATION &MAINTENANCE a o (FRONT ELEVATION) TABLE 25 TOTAL LBS. PER ACRE soma:Adapted from Installation of OUR,and Fabric ITter Barriers for Sedasent Coatrol,PA D57C PIAMN.305-2 TABLE 26 TABLE 24 Sherwood and pent TEMPORARY SEEOINGS BY RAZES DEPTHS,AND DATES MINIMUM CARE LAWN - COMMERCIAL OR RESIDENTIAL 175-200 LBS. Momtenonee FertSrso0lon for Permanent Sewmgs- Ranting - KENTUCKY 31 OR TURF-TYPE TALL FESCUE %95-100% Um. Soil Test Recommendation or Rates Shown Belo. Seeding _ w s°• •°t° arn ea' anes UZL and Seeding Dale ib[tn 36L - IMPROVED PERENNIAL RYE GRASS 0-5% Seeding Mixture Formulation s.pm Lbs.per Time Mowing o o In 7a speoies3L Pm a/loon and 7b ab all and sin - KENTUCKY BLUEGRASS 0-5% -_ Acre 1000 sf \` ' acre S.It (Inches) 2/1- 5/1-B/15- 3/I- 5/1-B/15- 3/15-6/I- a/1- Tad fesme makes 10-10-10 500 11.5 body,or as needed "Not closer than 3. 101 a0 4/30 e/14 11/30 4/30 8/14 I1/15 5/31 T/51 10/31 aP 70R or mere or If is desired.sets Z.+ry Cnvom me BY cr marring of cover. 3,10-10 400 9.2 fall Barley 2s ea. 2a0 1-2 X - 10/15 X - 10/15 X - 100/1 HIGH MAINTENANCE LAWN 200-250 LBS. Nu, 3 bu z21 1-z x - - X - - - - - KENTUCKY 31 OR TURF-TYPE TALL FESCUE 100% Cron.etch rani•mu'°War Do not mow o g est..- DESIGNED BY:JLF(VSMP) Ryan/ 25 bu. 122 1-2 X - X X - X X - X GENERAL SLOPE 3:1 OR LESS) Service lespedem 0-20-0 400 92 mme,in,ese.r 4-s cro.na. DRAWN BY: JLFNVN Raney« Birtlafoot trefoil years thereafter. Rye m•• Is°ins 5.45 I 10/I5 10/I5 X 10/1 - KENTUCKY 31 FESCUE 128 LBS. CHECKED BY: JLT Fmtaa X XXX XXX X X mlns 10/ - RED TOP GRASS 2 LBS. Fomy uniform Fall Me year Not required'an :of if •••••• a lbs. o09 1/4-1/2 - X - - X - - . - = SEASONAL NURSE CROP. 20 LBS. stone of tall fe1lo.:,g e.tmnn- a�Iaµm o.Ng la p1•TR Or' 'D`°9r 11 r TOTAL 150 LBS. resme s sernm 5-10-I0 500 it, mme and e.«r 4-s l,F' n� Anna w me. 1.1s 1/4_t/z X - 11n x - 11/1 x - e/ts LOW-MAINTENANCE SLOPE (STEEPER THAN 3:1) lespeaex°'° yeare Mmmnm. m°ml one.seed n'0 `' '° �e _ss b'rd•foot treffoa. lures // umea2G so mi. 1la I/2 - X - - X - - a - - KENTUCKY 31 FESCUE 108 LBS. Net regubed.not • 7 1�r s weeping RC Applicable m slopes of 301«natter - RED TOP GRASS 2 LBS. seNc lo.m. /a.�9 esttha:eh- closer Men v u HI Refer to figure A-Adapted Irvin usoA,ARs Mtecalaneaus wbncvtmn 6105,January 1990 &sends lespeaezd dorfuppl ma.mq 15 Jimmy L.Taggart fairly unN«m s-1D-ID soD Its mml ma eKry 1-4 ea d fail �e and sort,seeding dates,um y If ground Is frozen and resew when Mooed - SEASONAL NURSE CROP* 20 LBS. t distribution tie.al Between Ire IWI/earlyy renter permmment see5n9s.add Sa lbs/oc plan ymn Mereanw mat mad. Am G 226a1 �Kaa'' red to Ne pmnanmt sewmq mlXWre late '� e3'S2DNAL 8'0 u«rona state Highway Adminunaum Tampon.Sew 1. - CROWN VETCH** 20 LBS. September, Maw no closer Man usedELL as a nurse« mid-amen Ana 2 lee/ad TOTAL 150 LBS, Rea es.cnewin zo-Io-lo 250 66 2•fee rad fescue May ba crop I« «permanent settlings. 9a S30e toys later AV la permanent seed min fescue,Kentucky and Ky Mumma *USE SEASONAL NURSE CROP IN ACCORDANCE WITH SEEDING DATES AS STATED BELOW:May be new ne nurse fee midmmm«permanent aesdn9 Add to ens/a. i itur December. and closer Men 3• ALLa Na permanent sassing mix. eiaemxre 20-10-10 100 23 May 20-.mne-30, 144 Ie,a,e. FEBRUARY 16TH THROUGH APRIL 30TH ANNUAL RYE If needed. MAY 1ST THROUGH AUGUST 15TH FOXTAIL MILLET Z AUGUST 16TH THROUGH OCTOBER 31ST ANNUAL RYE NOVEMBER 1ST THROUGH FEBRUARY 15TH ANNUAL RYE INFORMATION FROM TABLE 3.32-C OF THE VA ESC HANDBOOK EL _U iS PROVIDED BELOW FOR SEEDING SELECTION ** SUBSTITUTE SERICEA LESPEDEZA FOR CROWNVETCH EAST OF FARMVILLE, VA (MAY TOTAL IRS PFR ACRE THROUGH SEPTEMBER USE HULLED SERICEA, ALL OTHER PERIODS, USE UNHULLED Z J co MINIMUM CARF'AWN 200-250 LBS SERICEA.) Lii D Q -COMMERCIAL OR RESIDENTIAL IF FLATPEA IS USED IN LIEU OF CROWNVETCH, INCREASE RATE TO 30 LBS./ACRE. ALL W Q W 90-100% LEGUME SEED MUST BE PROPERLY INNOCULATED. WEEPING LOVEGRASS MAY BE ADDED LU KENTUCKY 31 OR TURF-TYPE TALL FESCUE 0-10% TO ANY SLOPE OR LOW MAINTENANCE MIX DURING WARMER SEEDING PERIODS; ADD 10- 0 IMPROVED PERENNIAL RYEGRASS 0-10% 20 LBS./ACRE IN MIXES. Z KENTUCKY BLUEGRASS GENERAL SI OPE(j1 OR I FEB 128 LBS Q ui H KENTUCKY 31 FESCUE 2 LBS < 0 RED TOP GRASS 20 LBS CC C_ Z < J SAFASONAL NURSE CROP ee al LLO m •USE SEASONAL NURSE CROP IN ACCORDANCE WITH SEEDING DATES AS STATED BELOW: I- a CC MARCH,APRIL THROUGH MAY 15TH ANNUAL RYE < O H 0 O MAY 16TH THROUGH AUGUST 15TH FOXTAIL MILLET AUGUST 16TH THROUGH SEPTEMBER,OCTOBER ANNUAL RYE z 0NOVEMBER THROUGH FEBRUARY WINTER RYE LJ J /� O FERTUZER(1D-20-10 OR ES)SHALL BE APPLIED AT THE RATE OF 1000 LBS/ACRE. I- V O O - AGRICULTURAL UME SHA BE APPUED TO SEEDBEDS AT TTHE RATE OF 90 LBS/1000 SO.FT. Cr,LL 0 SUGGESTED TEMPORARY SEEDING MIXTURE . Q O W FERRUZER: 10-20-10 1,000 ISO/ACRE Z /TS SEPTEMBER-FEBRUARY 15: 50%ANNUAL RYE&50%WINTER RYE 100 LBS/ACRE (.� �J FEBRUARY 16-APRIL 30: ANNUAL RYE 100 LBS/ACRE CC MAY-AUGUST: GERMAN MILLET 50 LBS/ACRE OTHER OPTIONS EXIST,SEE VA EROSION AND SEDIMENT CONTROL HANDBOOK. SUGGESTED PERMANENT SEEDING MIXTURE UME: 2 TONS/ACRE • DATE OCTOBER 25 2019 FERTILIZER: 10-20-10 1,000 LBS/ACRE SCALE N/A JOB MARCH-MAY 15: KENTUCKY 31 FESCUE 200 LBS/ACRE,ANNUAL RYE 20 LBS/ACRE FILE 1 0 125 9 MAY 16-AUGUST 15: KENTUCKY 31 FESCUE 200 LBS/ACRE,FOXTAIL MILLET 20 LBS/ACRE AUGUST 16-OCTOBER: KENTUCKY 31 FESCUE 200 LBS/ACRE,ANNUAL RYE 20 LBS ACRE NOVEMBER-FEBRUARY: KENTUCKY 31 FESCUE 200 LBS/ACRE.WINTER RYE 20 LBS/ACRE \,\ J � ,,SHEET' OF 9 Drainage AreaA STORMWATER DETENTION ST71EM AND LAYOUT SHOWN ` m Drain.Atm•Land Career 1=.e0 IS BASED ON DESIGN/DETAILS VERIFIED AND PROVIDED y o --- - - .b. of ,,. a.. BY ADVANCED DRAINAGE SYSTEMS (ADS) UNDER GI .n a.,k r .. 000 000 SEPARATE PACKET. THE PROPOSED MC-3500 CHAMBER r o'i< Yampa 1 - - _ -- o o.m _ SYSTEM CURRENTLY CONTAINS A DEO APPROVED c�•' rar axw,>,.w,n,.eta.,ro,=.,r.ow t d. t f° D I-3 B PHOSPHORUS REMOVAL RATE OF 40%. THE CURRENT 8 ,§1 1 r 31 1 ,...re„am.,o.x o.es Total o.n Past[Mammam 'mamarea Vaunt..o. I REMOVAL RATE HAS BEEN APPLIED TO THE VRRM V2 I-a, n r_„s Curb Inlet Calculations SPREADSHEET AND OFFSITE NUTRIENT CREDITS WILL BE YJ] aS m Stormwater Best Management Practices(RR Runoff Reduction) ...., -.k+. Location =On grade Compute by: Known Q PURCHASED TO SATISFY THE REMAINING PHOSPHORUS Q Q V i-E eN.. .,...era.Impena. enRemaining Total,IMP x w..,,,.,. Untreated w=,� m%Y w „ ,,,rearLow „� ,r,e*. Curb Length(ft) =8.00 Q(cfs) 1.64 LOAD REDUCTION REQUIREMENT OF 0.81 Q_ a La,.. c.der Wawa... `E„p,reedk` x sea By,0..0en Throat Height(in) =6.00 ad O Z a Pratte ...MI leeal e.e..mil,Area Cc*,UNIX n...motel ei°x`10"'"I mmm,n'. ao.m.WI Peer "' r _e.,. road.P1 ercrceisi en. r.cm 1 uf,.). ow (oft) Um ..,a n.r rel on °i Grate Areas =-0- Highlighted Q � Treatment Re...al Efficiency ,r. rank r.en O Total cfs1.64 0 Grate Width(ft) _-0. T I <Z ., e...,.D. .. t 0 D L m Dx 0. Grate Length O =-0- Q Capt(cfs) = 1.59 Z om e o -_- -__ _.1 _ _ _..__. _.__.f --_- ____. .°'_°_ 0 B (cfs) =0.05 ,.D w.w.m�freemen -__ on o ,.,,, ,.,ne Pa o.x I Lae _... I _ = am raw re - 7. Gutter e ftDepth nlet(in) =4.84 m> _ _.__- .-__ - a I ,rer vm,..D._7._mre d .o ono I Dx ow o.w ' 0 000 0<0 ra Slope.Sw(ft/ft) =0.080 Guter Efficiency(%) =97 w t7 t Slope,Sx(fUft) =0.025 Gutter Spread(ft) =5.06 0; 'b r ®...^.e'..ff.d,^-.rr.d"-o^".,....,.^'ss•...a..01.•"30 sae Resales(Water[bulky earnpsancel Local Depr(in) 2.00 Gutter Vel(Ns) 3.81 '� aW n i w Gutter Width ft =2.00 Bypass Spread(ft) =0.83 -ae......r.�.r..... ,:m.,D......,.a...awe.,,... Gutter (% =2.50 BypassIn =0.80 I .a" n nre,aw. a.. �m Slope( 1 YP Depth( ) o w-.: rt<•', Gutter n-value =0.016 0 �.a. . ..r.7eq...e�,. a..,DN � DI-3C I o' LG t>o 2 n Site lMormatmn m.e.ec.00ot.. oic Site Treatmeeoeoaneln'I1'F"" Curbinlet Calculations �` = , Post-Development Project(Treatment Volume and toads) L - P Y Ru,.e..e.mo.vdrm....Ener er r.er.a_ Curb Lenngth =Sag.0Compute - =KnownQ n.abcte p1 e d °;` '; °Y Throat Heghtft(n) =6.00 0(cfs) =0.70 •"" ..,o...e...w 0 ow a __ . Grate Area(soft) =-0- Highlighted •� ado 7., +• ,I __ ___ ew • Grate Width(ft) _-0- Q Total(cfs) =0.70 --, ,. ,. ,...red....,.r.r .0 0. • ono) o. Grate Length(ft) _-0- Q Capt(cfs) =0.70 .rr.�,..k.rc , wo " .,rem.,o.D m,k7o..mv,n.e..a a. I D. Dw I ow Q Bypass(cfs) _-0- 1 na Gutter Depth at Inlet(in) =4.52 ..wr.e.re..l 1 =d'•o„ 'o^aw n Slope.Sw ft/ft) =0.080 Efficiency(%) =100 \ a --. 1 t,., e,. _1 .,D.o.mrrr.x.mD=0.M S Sz(Mt) =0.025 Gutter Spread RI =4.00 g ▪ _ - _ ,.,De..Fm..r..r,Dry JJ lope. ) ,..0.=w,..,D rv,... Local Deer(in) =2.00 Gutter Vel(Ws) =3.81 - a .._.._,... am o.. ow aw ,a Gutter Width(ft) =2.00 Bypass Spread(ft) _-0- �_ • � W..n . rsr x10-..,lr>Ira,.ra.n....v1 Gutter Slope(%) =-0- Bypass Depth(in) _ Lid ) o M Gutter n-value =0.120 \ _ l/ Post Development Requirement for She Area „dw.wnavn0..wm.naax,m u • 1. -�y ,mu.u.reOrD,un d.mare .. .ore, n. • " _- _ rn row re,11“.. , y. yy v,... era. .e...,,. F i Pe ..._...�. --ww.,.,r...,,.. <: m7..mwosm..�kor,om„wr..d.re.ay..e nor- .s - - .ram* .+w..r..... u_ rem..re.,,m.w,5..,..,we.m..,.,,.....,00.arrnu.o,e _.__ �(f v.v. urwerrequunemepnrmraeroo«.rrgmnrurrr<,ru,..nu. ; I ( za ...x__...-, ,-, --- .,.,,,e...,o,.Omu,Du , ..r - I.. J W w«.x.r D.D..,ae_ ,73 • © a j M... G - 1111111115 \----T.::,__,,',•‘,,.....:,j,.",,.,. ''.--.I.L,-.1:•._,-, .,\,, .,...L.' , . •C o Milli I\_.I , • r/ i 1 % DESIGNED BY,JLF AMP) -- \� ( DRAY/N BY, JLFNVN OUTLET STRUCTURE DETAIL STD. MANHOLE LID 1 �' t _CHECKEC BY: JL7 NOT TO SCALE FOR ACCESS �' �1 i i / 1 4 `�T- S.O. 1 i i i 1 1 .`sLTH py p` 4 P STD. MANHOLE \.T�� �1tfr. f• z Its t11r `J. / °y STEPS % ..Ill��� INV/' �, 1 �1g� (� o T / X U MI \�\\ ./ 4%�_ I s�1�11j1�%;Uipy Jimmy L. Taggart Multiple Outlet Design 602.0' 111' b 411 e�. ua Ro. r Outflow 5.0' ii/ ,.. .i• 0�� 1' ll nit °p.. neAt 4ti4i �� . .,� �4elpaA4Total Discharge: 646.0193 cfs r ./+ ih- .,,iWater Surface Elevation: 610.00 ft -' �� /l:' t a Tailwater Elevation: 0.00 ft Detention Base Elevation 0.00 ft ---- - ` , --_ -_ OUTLET JUNCTION BOX WV our If*I • `er 4. �.• �/'' Z Outlet ke TMH,op Drop Pipe r- �\ Riser Top Elev: 602.00 k 9.0' H % 5.0' W �e r� t �' '�. EEE: Riser Base Elev: 593.00 ft ----- �'� - !, Riser Diameter: 60.00 in .•��` / - v l d U Orifice Coefficient: 0.60 ems'♦ i r• Z Weir Coefficient 3.33 V e -`-'�- - li '''y - W D Culvert Length: 20.00 ft Culvert Diameter: 18.00 in '•= / W Q Culvert Invert Out: 594.00 ft n (� g to Culvert Friction Coefficient: 0.01 _ •v �L`'' Culvert Entrance Loss Coefficient: 0.10 ' h.'• : 'r Q 0 0 J 3e•ORIFICE O 597.10 I ,' ,S4 \ Z E I- Discharge: 37.74 cfs 2 Cl � s45 599.0' - - - INTERNAL WEIR PLATE 4.0' H x 5.0'W (+,' 0 S o, cc p Z w W Outlet �f2: 01. Orifice FOR OUTLET FLOW CONTROL. INV 0 599.00 > Fa Shape: Circular - - _ - - - - _ - - - 10 YEAR WSE =598.85 ---_ ,. Le a> O Diameter: 3.00 in - re• e' Q O c1 Z Invert Elevation: 597.10 ft 15` INFLOW HDPE PIPE FROM DETENTION CHAMBERS 20 0 20 40 60 Coefficient: 0.60 Number of Openings: 1 - - - - - - - - - _ - 1 YEAR VISE =597.46 SCALE: I"=20• M w VT Discharge: 0.88 cfs 597.1'- - 0 CD 0 Velocity: 17.20 ft/s i . CC Outlet g3: PLATE. Weir Q OW Shape: Rectangular w/o Contracted End Z Crest Length: 5.00 ft v Invert Elevation: 599.00 ft . 0 Coefficient: 3.33 - CC Number of Openings: 1 -- 595.0' Detention Chambers Stage-Storage Report > Discharge: 607.44 cfs Velocity' 11.04 ft/s Elev(Ft) Storage(CF) Storage(CY) Storage(Acre-Ft) 595.000 0.000 0.000 0.000 t 596.000 2080.679 77.062 0.048 DATE OCTOBER 25 2019 - - - 597.000 5271.845 195.254 0.121 SCALE: 1'=20 598.000 8335.483 308.722 0.191 JOB GTH 20 LF OF 18�HF 593.0' FILE 190125 OUTLET BARREL O 5.0% 598.750 9719.302 359.974 0.223 INV. IN=595.00 INV. 0Uf=594.00 - \\ 24.DETENTION SUMP CHAMBER SHEET OF 9 • • 1 . , .rr PRE-DEVELOPMENT 7;.....7.:0,..1,,-,; _- ---'.•So.Ils. o.0sc.. POST-DEVELOPMENT 7,.., CNO NACCLCUOSRIODANN' CE WITH CHANNEL PROTECTION SECTION SITE AREA-0.88 AC R "'":"' ,Imme:.:9m•E NoW-Zom-.m`yfoin5 im?-:-Iwo : 24-HOUR STORM FOLLOWING THE LAND-DISTURBING ci .'? /°----- "---' .e..i..9A-..i.,,a.—r,-.-. , , . ) SITE AREA=0.88 AC ----,:::, ,, --:, .4",,,,,_. .41i..".,1 7,.......a. TR55 Tc= 6.0 MIN ‘__ __,,..._ , 1 ACTIVITY APPEARS TO BE IN ACCORDANCE WfTH THE mB A.3x.Ai m)u Om F p9E AVAKC 2F5L-0 w8713R A-T6E6 FORE°mV I prGHI EN I AoNL AE W_y;EAT H E O 6. '- ',.il A -ENERGY BALANCE METHODOLOGY: TR55 Tc= 8.0 MIN ..... . . ... ,,,_1--e------",, . \ CN-90 , "',-."..:t7.=:,1'..7,== r:, i ':. I ::: I •< 6L6' i 9 T0 . CN=59 swo„ maw.,retivro(WWI 11.1.31an't2"7" ."..:.:7"I : I'; il . . , errywnece L ...___: 9. i ..----J )- - - -- \ °- '4 P, • 411,-,is, IMPERVIOUS : : , .'. QR VD PE VR EE 1---% ::0 02 5 0.90.(0.27.0.32)/2.02 OR 0.02 5 0.04 PEVEDELOPELDF). ...? 6. E5,, r0 I ,1' " " • ' •., '___v:-.- --; • • _---- ..,-, ' I I--, -- CIOUINEL PROTECTION COMPLIANCE SIJIMPIW TAB. C (P ./(ROvPDRE vE—DEVELOPED 0E;EELDO P E D I . " EXISTING _ ,---— If ' _L-4:\ L' , , ' 0173DZ • „. c6.n.c I' 1'Hi Z c V§ 2 . ..„,•,, - „. , , I, 1--,,--?- .41 kw.wa,, ,,, ,;,_„ ,,, v.._.=::::',H o.......re•--. w vt.-, °,,,=,,,%.- ---"I i-11,11______-80"PROPOSED , , 1 1 ' '',... ' I 1----'.„, RIGHT TURN TAPER • \_-- ""-"' , I i,,.:s.3. '":1---:3,23-':"::-,Zi #1 ='''''''''' ' 0.078 i----,P.."'l ¢W rn '2 ''.3.,"...., '" 44.‘1, EXISTING v ,........IMPERVIOUS ''....• ..1'..L.Gr.. 0.07AC rn . • .., _!4•;,!-Ai -- ,--1'-•-_.-±Ff,..,-,i.1.1 --,:,-.=---,-1---,-,... 0.18AC --41-',. .'':- ',.,:=7:::: , ' '"',37".2'.'";7'''n=v''':.,.............. • ‘- - _-±Tr- i- I ,1_1.. , 7,8.6: L TMP 60E-1 DYNAMIC INVESTMENTil' :KV.i_--',A • ____,....._ .,_ ,,,, •. CAPITAL ENTERPRISES 4'4•:--:. ' t•4::,:..4,44.s.n."-....'''''''''''''' .. . - USEZONED: C-1 I r:'I,NA, • - - .--=1,..,.,,..„..,=-1-, 1- ,?...A.r , fx •,••:. OFFICE BUILDING I'' _‘4':`,411 °9::::::..: 9,4i.m.nn.i....9....,:xmnn.:,..., EXISTING _-_-:--- ' 1 ,..,.4.1 F BLIT- '04 , . ,-,---'''---- — — - - - '---'- I ..... .r,".!"-"-- '13:741' ... IeljiWT7i-fI • TURF .,....--= ""- ... ''''....--,,....:--_,..0,--—, ;-.... 4 1. .0. ..".6..0-MIN•••• . 1 0.08AC ' . ..->-' ... rr..„.- ••,.„=„:-,-_----_...--_-••••,.- ,_ T. _ , ' 1, • 1' .•- , -, ...._ .,.-..._,' ,--r''''" '.: .,,, 1 -- — • ' • -"--1,,,,,,ki \..;,*.. ------ - • • - , . , -- ,,•;=-.•-•-•-•," ,„,- - -...!_•.--,-•,--7 . •• ---, - ..:•••- \ \ -,_ .,-...tr_. . .•;-.v.:,..-,.-:-,..„-- -1- e,„ 0, ____,..-...... -.-- , , . , c, -,40_, ,--' 1., „, ill - :661,"o".‘1, ..!-!•T'I'L--:: — .1....7---tv..,,---. ---; —l.r.)S1 \ . \\ I,\ - - -717-7 ,...,,.z,„.,.. .,. ..., . r-,..,.._.•:-.4 —_,--. ..; : , \ 44 w't \\ g 4,'",,,%. 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(min) (min) . i, „Name Subareas "ere) _ - C0a.88 90 6.00 6.00 IMAM Filet: , , CN Te it ' I ' DATE OCTOBER 25,2019_, , Subarea Downstream Area REV-17R_POST.hyd • Name Subareas (acre) (min) (m,n) Inflow Hydrograph Curve: DET PIPES.cop - - -- - SCALE 1-20 'SITE-PRE 0.88 59 800 8.00 1 I I ' , , Computed Ran It Stage-Storage Curve: Stage-Discharge Curve: DET PIPES.stg . / / ,„._ ,, 2.807 tIn < JOB GTH Computed Results, .. , Peak Discharge(Qp): / °-, .--I: Results: •:,/ 12.10 hen FILE 190125 lime to Peak: 2.81 cfs ,4E1 - -IL 60 Inflow Peak now: ),- 20 0.272 cfs u'r / / 0.09 acre-ft Peak Discharge Op): Runoff Volume: 12.10 hr \ 12.10 hrs / -SO_ 0 ..-- 20 4-0- 'sp , Inflow Peak Time: 0.02 efs Time to Peak: , • ' Routed Peak Floe,: Me6S1571 . 23.50 hr 0.01 acre-ft ' / MMEM-11.M.M.NIMEiliil I\ \ Routed Peak Time: SCALE: •7=20: ,, Runoff Volume: , io ' ' 0.1328 acre-feet . -'-'• , \A SHEET: 8 OF 9 / - ... . Maximum Storage. ,. , SCALE: 1; S0', ,:: ' --\ .. 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'`Crr r '� ° J C i \G'�� w v A .A I ' + 1\ '1a / �..i // '�'2-- I 1'• 1� 0 �Q� A ] I 7`� _^ a o �..�� 1 t 1 I a e �. •I i, _.,.'''''-\ \ 0 1 o a U_ r o''rPLel I ' i I I 6 s�o?' rr�t."- 11 ey ff 1 , / v I I v \\• a � �i 1 t- ::41:1:L:11...,.....1)1, Q �. m -� 2a"P�hF �dPo= V I w _ - I ."J to"PDP 12a PINE y i 10'itPL; I ' I 1 N N , 1 z It. pmpa \ 11 I `'\x 1 Q�m PRESERVATION 1 i !•"' e I 1,\} !L-�\ \ 'e+D'POP i 1 �I Iztoc i� �7� r �, x lo'Poa �� a A I ( 1 s_ 4: : v `i C�0 lot I h 1 P I I ,- t 1 GQ ' �. I �v i 1 1 P I �a��1� S : o� , ,f� I i 1'\ Q DRAWN BY: JLFNVN I \ " I \ 1,' 12"SASS " , .Q r 20'�.Id, I, \ tl DESIGNED BY:JLF SMP ` 1, K ll 1 I x'' % 1 \ 1 �, 1 I I ,'., Q O 'CHECKED BY: JLT f , a l !� \,`, `. .I� �` 1 I`.t ,`\ �91 I c a a�' u k , II �' O CHRY /�. /r^ / J 18 Po?�0'MP I 1 za'CnR r �0'r^iR1 1,. � la'MPL (�' } Yn 1� -1\� It '1 .\ rf JT ttt ` 2 1 r `�' I�. 1 n c \ t too ,6EEN \ 2a'CHR>4 "T '` IB•Mat15 r ",,,,•✓ ,\ 1 I , (/ ;{''E 1 \-�\ ;KEEN \ FT• } /1, 'wY \ `\\\ 2 xl �� , 11 1 . ,G �p1. F F t t' kY+`'-KJ 3"1.1?`'�l (, t+-% j \•\\, I 7 I'�..{ B"TAPE'-i i t P 11' �' e--e= 9 ., 11 l 1 ` rF l� \ I ' 0'cH I 1 -6 \ J�, / 1o'.cH I 1 11 Ai,��_ ��y1�-_� 1L`4 1 /' TIAL ) .1� 1 � ' I I 1 I l .'C IT1AL ) "a ! w.✓I I I) I I I I I,K \� if �t�' •u 1/1 1 1;� ( ''1 ' EA r lie R it'4'' EA / J '�/+�(JI�� ll' I r I 1 11 1 �� t?'POP I �(, t0"L1PL ,i �V , \ I �y f f 12"POP 0 R 1 7 / i I b' �, V , ] J 9•A7P�r / I I 1 tl' , 1 1 , \ / /� 113"'!P 10"VPL. 1 I \ / b / / / I I , % 1 1t i :L'NH FEr:G-� o•o.I I .„1 1 vuNK FEN2E PPI ( l I' I 2DTP, r �::, tic.No.99 + \ O'J Y / \ {7 Y \ \ \ \ Jimmy L.Taggart - CHOP O'pDP ! /r""�� ' 8"SIPI' +f. 20"u0P I \ +C P'J? C'a0p I d'MPI: „et., 1.,E .\\ I \ uAq '4:, \ 0 22841 q4a` ` K•j'LY : i I .•'i', \\ ° t BENCHMARK \ �^G/ I B^OAK I i 1 1/ 'I I IV 4 .�. •^ r '1 I �V es 04 \\ yCA �e BENCHNARH A l ? �,`� 8"6 C 1 ,K '� 1 � '¢I CP ,�r" 4 •+ `ELEVATION=614.19 " •[ Y' > rOF �20'POP , TRAFFIC BOX Tg p `. fi'S C 1 IB'?Oft i ='T!f �� I. �, I ,_ •IiRAFFIC Bl1X 9 4� • ,IY`'� ' •. 1 I DP 1 ELEVATION=61<.19 \ f��/''l I 'lp /q y;� fOAA1 / l r; 1,:]1I1L5 �,, I 1 , ( x 1 OP W.- a ._I P _ ��',�I)� `J_" I\ 'i ' 1 r 20^POP Y r d,11 .4, + + DISCHARGE 1z'po 6,..,,vpoqf;;Coy' is ,zuPOPti• f- DISCHARGE Po 4 2� 1 1 Aq l 1 12•Loc I / \ `Y 0 //f_n"'ji' / (xIGG�v' #1 ' I w 'I , w •� I r Po1Nr`.#z `�+ I11 A � ,r // JP, I,�_'"1 ..� '^ 1 2'i.\ (nEAD o � P ` Itfi'D .�� a, - z•. a • 9? 12'P�'�,IQI_ `l�_ \ • \, \ ,tr'I \\ !V W s ! .-�i' '` _U• 1 \ - 12'P�P'IC] • 1 ^-"' \ `', •��..'t.`\\`'' __''�, ^�A'.-�o Uvv` .1 rV " 1 V IP\,/.`02"TJC a,S „o+^; v �^'J` 1 •I / !yam x /rPDP " I ) �r I�. 1 I \ ,\�\ , �,:' �• n_ !, ' a2"DAK%2 S • 2 R " . " i' / 42"OaKr2 2"\ tea.., -/ A x / t ? /, I ` ` is"POr•• • . " L4/ 1 j I { ; `2 1 `} ,`1\\� . •>�..,. .:zaer A!^!�� Z _1 W " Y/ I= I p� i' , i �i�T�Ow v,L° . A \` ,fir'•, ' _:..0; •O `� �1, , Y� / III Y:, .12, "-he < Z / 78"OAK ¢-- \\ / - f /� b,. ^L l %8*�K YR'�OP p P 3 " W �.a'OaliRi + Z C •`�„f ' / / �. / ( IB h1-1.1' I in l\ /L`/ e /. i�1 I.E d.E, - �'` w Q Q / � ' �_h % i1V r�. 6'POPO• tW • �/ +--� �• `�ti/ f / �/ 7 i / 1® \\z91 /� • 4., ;j tI(I �/, ma z d /T / 1 I "'y,' �'•�,✓ a1W '"'� o'Y . " .. `•" r � / I ,1r •F9 \/v.,�/ -� 1``\, / _ / V_ '^ x� �...:.M, QQ9" \ - 1 o, I • 9 ° "?a\,:z'PD - Jo"�c� ` ,, " - ?,;. -1/- p eo i. j „,, \ \, Y �� r� 1 i'm• a`4`o� ^4" ,.rl%!v ® + +9., ^ ^ :; Q �- -> O % / - 12"?u1E 9q NL e MPL7 , �' JL\ `�_ „1-,,A,,,,„„, \ . �-„c,' TI. y, / I�71NE , -I \a r' ':ac _ - -Q// / kidIif rf m l g gip+ �o '/\\ _ '�Q,• 1 rid- / 36'OAKx2 \ V %r,' /� 4,' 4'; ;-pO° IPP = ' " , ,','''''\-..-'-' I/�'• "3' f •OAKX2 \ 41 \ %��/ -I r ,..a.- ,a.. / .I ��+ p '• ¢ ¢ O / 1 / " '' _ '1`WJe r;'� ry �, yes: /� I °`I r , ,R JP Z 1 10'`,PL ( • " ;,r/CRY =,YC' 1I1" (OEaO)!��-- �.✓ Q" / / .:e' 10NFL / ;^�yC� I /�I-1I yes' 4°. y �A I� _-_ � .0 ., O L0 / h ‘'." AP,•l W %. " PL 12.dAK• "1wa`, 9`'.j.5▪`'' \`T / / ti, % (6 '�i►- i,d" T -I 1- 9 ¢ O Z PRE-DEVELOPMENT- t �� • ! "_ (�`. '°o 'd PftEPA�+ -POST-DEVELOPMENT ' • - I _4'30.V•III 11, ,/,1-I tl rR' � yea o Runoff Hydrograph:TR-55 Tabular Hydrograph Method- -- --- " I� y'� Co Q M)N Runoft TR-55 TaDutar H tlro h Method" -�;�)r� I Yin dp S/f �/� (n C- In I' `b'(i ,E11 Hydrograph: Y graP I,I_� s �l O Input Data. • Inlet' �='�" P w�- Vim' v Input Data: I I \ f" � / Q �7 \0^. - I Q u. I Rainfall Distr+bubon Type: Type 11 n \, q } /' ^C. O Ra'ntall D+str buf on Type: Type II 1• / // Rainfall Depth: 5.57 \„ I{y / ` Ra'ntall Depth: 5.57 i \ TB�� `\ � <r % `6164��1�,, �/ 1 �1 w Base Flow: 0.000 cfs \ "-"'1 Q�Up ••,v13,�/ v Base Flow: O.ODO cfs I '� =f/j V' -aka/ Interpolation: On 1 I la/P Interpolation: On I / J' '\ / /}� I / 1, I ' /_ / /`__.•_' �' ,/ / '3AA�. > Subarea Downstream Area CN Tc Tt Subarea Downstream Area CN re it Name Subareas (acre) (min) ( 'n) 1 Name Subareas (acre) (ruin) (min) Reservoir Routing:Storage Indication Method 'DO-PRE 0.37 71 8.00 8.00 \ r / 1 DA-POST 0.72 92 6.00 6.00 Input Files: Inflow Hydrograph Curve: REV-IOYR-POST.hyd Computed Results: \ _ Computed Results: Stage-Storage Curve: DET PIPES.cap DATE' OCTOBER 25,2019 Peak Discharge(Op): 1.229 cfs �' / \ Peak Discharge(Op): Stage-Discharge Cr,ue: DET PIPES.stg SCALE 1'=20' 5.280 cfs �' Time to Peak: 12.10 hrs / .._ Time to Peak: 12.10 hrs Results: / ,- - _ JOB: GTH Runoff Volume: ' Routed Peak Flow: 0.04 acre-ft '-BO _ 0' 20 40 '`60 Runoff Volume: 0.17 acre-ft Inflow Peak Flow: 5.28 cfs -SO D' / 20 MHO FILE 190125 / Inflow Peak Time: 12.f0 hr - ' I' ■■■ •E ill \ Routed Peak Time: 0.09 hr ■■■■o r SCALE: 1�=20% / Maximum Store 0.2058 acre-feet SCALE: I%=201 , /' \ Maximum Devotion: 598.95 ft / / // • . - /� SHEET. OF 9 / SITE DATA U OWNER: 400 LOCUST HYDRAULIC&GEORGETOWN LLC PPP F O R 400 LOCUST AVENUE, SUITE 3 - h CHARLOTTESVILLE, VA 22902 - - DEVELOPER; BMC HOLDINGS GROUP LLC CD 2O 1O z o 400 LOCUST AVE, SUITE 3 °i 3 L n CHUDABU H, GAL VA 22902 GEORGETOWN HYDRAULIC Q o co' U PLAN PREPARER: RO400 LOCUST GALE &ASSOCIATES ctdn .y s s 172 SOUTH PANTOPS DRIVE 3 _ CHARLOTTESVILLE, VA. 22911 W j (43F-00-0021JACK JOUETT MAGISTERIAL DISTRICT TAX MAP PARCEL No: 060FO-00-00-00300SHEET INDEX PARCEL AREA: 1.05 ACRES SHEET 1 COVER SHEET ZONING: NEIGHBORHOOD MODEL DISTRICT. PARCEL IS SUBJECT TO ZMA2006-14 WITH ASSOCIATED PROFFERS O AND CODE OF DEVELOPMENT, AIRPORT OVERLAY AND ENTRANCE CORRIDOR OVERLAY DISTRICTS ALB E MAR LE CC)UNTY, \II RG I N IA SHEET 2 POLLUTION PREVENTION PLAN a 5> o PROPOSED USE: PROFESSIONAL OFFICES SHEET 3 POLLUTION PREVENTION PLAN NOTES&DETAILS <to M n3. BUILDING AREA: 16,815 GROSS SF, MAXIMUM ALLOWED nm 14,289 GROSS SF, PROPOSED(INCL. PARKING LEVEL) OIL / BUILDING HEIGHT ALLOWED: 2 STORIES: 50'MEASURED FROM FRONT FACADE WP0201900061 3 STORIES: 60'MEASURED AT THE BACK TO INCLUDE BASEMENT BUILDING HEIGHT PROPOSED: FRONT 32'MEASURED FROM FINISHED FLOOR TO PARAPET PARKING SETBACK: 10'MINIMUM '_,� '..,4.;,'+.?. . -'.-F,"_1-T-..-t�;. :-. BUILDING SETBACKS: (IN ACCORDANCE WITH THE GENERAL DEVELOPMENT PLAN) -^y — I; m=, w Sp ', e'` �.:�6%)',, MINIMUM FRONT SETBACKS FROM BUILDING CORNERS: 9.63'& 13.47" \fl.i \ 1`. \ � `�~~ , ^, FRONT SETBACKS FROM CENTER OF BUILDING: 15.22'&21.85' - r':' �\�A--/ ''�\"�"^7,' 1 '� /� BUILDING SETBACKS FROM THE RA ZONING: 47.50' ^` '� '- i�1 � r` .\�� ' El AREA SUMMARIES: TOTAL BUILDING COVERAGE=6,765 SF(155) 1 - ,y \o "r�r/r L TOTAL IMPERVIOUS COVERAGE(INCL BUILDING) =20,765 SF(459) .� q��L� f{�� W �.`*�'�'"^�J� E. TOTAL OPEN SPACE=24,973 SF(55%) j 'ma y. � \ i111 / �� _ f � d • MAGISTERIAL DISTRICT.. JACK JOUETT MAGISTERIAL DISTRICT 'I //l/,.� ��t i t,,:2�k�-.. `--_''' ' �-/ WATERSHED: IVY CREEK(A WATER SUPPLY PROTECTION AREA) j SITE / � :�..,, i +, y [,''-yam �t}� ,,. •• o BOUNDARY SOURCE: SUBDIVISION PLAT, LOT I, "GEORGETOWN GREEN"PREPARED BY W.S. ROUDABUSH, DATED JUNE 20, 1967, i \ ��- �h I "4�'/" �� � C7• ~ RECORDED AT DB 440 PG 93. 1i ai a 'C/1�Y�,. z TOPOGRAPHY: TAKEN FROM GENERAL DEVELOPMENT PLAN BY DOMINION DEVELOPMENT RESOURCES, LLC(2006); TREE 4• \� I ��`—'J'•4 �, - /\ :, '� S O z SURVEY BY ROUDABUSH, GALE&ASSOCIATES JANUARY 2019; WATERLINE LOCA DON CHECK BY ROUDABUSH, 1 q ,��,Y/yIC �\ G GALE&ASSOCIATES, SEPTEMBER 2019. 6. `2A' N /� �b'"�• "/ /47 ,'' O rx BENCHMARK: 7RAFF7C BOX 614.79. TAKEN FROM GENERAL DEVELOPMENT PLAN BY DOMINION DEVELOPMENT RESOURCES, LLC � I /� .q�•�� �4 1\ ��`p '�7 �`1�,r�,���;��pi ,1. `� o g g (2006) v /%1A. DATUM: HORZ: NA VD 88 VERT.: NAD83 \y/£ �'' l µ �/ %� �.ti. \�/ i > y FLOODPLA/N: THIS PROJECT IS LOCATED WITHIN ZONE X"AS SHOWN ON FLOOD INSURANCE RATE MAP. COMMUNITY PANEL 1 Iy'��" '''`sJ";- jx �� i� ,J 0 0 NUMBER 510003C 0279 D. EFFECTIVE DATE: FEBRUARY 4. 2005. \/ �o '(�' .TY. _ _ \/// ` •�fl/ \�Ci PARKING REQUIRED: PER GENERAL DEVELOPMENT PLAN, 1 SPACE PER 200 SF NET LEASABLE AREA = 9,376/200= 47 SPACES //15. g'r a' e•� ' ,ff Tom \ ry o PARKING PROVIDED: 50 PARKING SPACES TOTAL OI F' '\\ //_ q g 0 \ �1�`1 \\'i p� o o^' 2 ADA VAN ACCESSIBLE SPACES.. Oja " � Y M m •3 SPACES RESERVED FOR TMP 60E-1 PER DB 1591 PG 160 17,/ j � a � '"' �" /�"� '�° \�rt •x,V ...ACCESSIBLE PARKING SPACES AND ACCESS ISLES SHALL NOT HAVE A SURFACE SLOPE GREATER THAN is 48. /^ ' z""^' 1�r, '��d \C ACCESS ISLES SHALL BE AT THE SAME LEVEL AS THE PARKING SPACE THEY SERVE �f�'�'_'i', >'y�, 'ry,.'' P '�„" , ' s,✓/ RETAINING WALLS: RETAINING WALLS GREATER THAN 3 FEET/N HEIGHT REQUIRE A SEPARATE BUILDING PERMIT. WALLS S �,.•� o S`°I�, 1�1 "^ 'DRA NED BY.JLF(V NEXCEEDING 4 FEET IN HEIGHT REQUIRE AN STAMPED ENGINEERED DESIGN. PLEASE SEE RETAINING WALL C� ,�� fd' 1r-. o E� DRAWN BY: JLFNVNDESIGN BY OTHERS UNDER SEPARATE COVER. z , �'" ",;J?� 447��''. CHECKED BY: JLT NO EVIDENCE OF A BURIAL SITE WAS FOUND ON SUBJECT PARCEL. - ,�i ,i10%e rT '-$ �48P�TH 9 Y`. NO STREAM BUFFER(S)ARE PRESENT ON THE SUBJECT PARCEL. 3 ' `<4' �t4,..-,'AI:\�telo •� "- THE SUBJECT PROPERTY IS NOT LOCATED WITHIN AN AGRICULTURAL-FORESTAL DISTRICT. z `/= � b��S c' v l • "'.i'r" ' l�.—,^ !��3J \ JimmyL.Taggart THE SUBJECT PROPERTY IS LOCATED WITHIN THE JURISDICTIONAL AREA FOR PUBLIC WATER AND SEWER. �1 l <'<y_ 4 s -+'- e.No.99 4 t -----_-,,,<-'''''--- �.•�"=- lt, Ssroxnl.ee VICINITY MAP z SCALE: 1x=1000 FEET U z J w D • Q in < N w Z } w • _ _. U cc w ° m > 1— > a 0 Q o o U D_ ., LUo EL O 0 U I— CC 0 LLJ V C/ ti DATE OCTOBER 25 2019 SCALE N/A _ - JOB _GTH _ FILE. 19 0125 SHEET 1 OF 3 �j / Zo 0 20 40 60 is Li • _ i • SCALE: t'"=20' z 1 17 0 zm zr i.; �' 1 Li I GENERAL NOTE: Ce) gdi 3,1 n ,1 i ' l',':° i I POLLUTION PREVENTION ITEMS SHOWN HEREON MAY Q p U z o a - ' ' 1''•.• 1 NOT BE APPLICABLE TO THIS SITE SPECIFIC �? ul _ f. 1 1 I CONSTRUCTION. ITEMS SHOULD BE USED AND • --- ,. 1�so'PROPOSED REASONABLY LOCATED ONSITE AT THE AGREEABLE W 1' �--iRIGHT TURN TAPE! • DISCRETION OF THE CONTRACTOR AND COUNTY 4,1 ' • j1 'Tl,1 1 j INSPECTOR. ADDITIONAL POLLUTION PREVENTION ___ N C7o� i r = �I I'' I `CONCRETE' MEASURES NOT SHOWN HEREON MAY ALSO BE w TMP INVESTMENT60E-1 - ___I s.. NTi a Z DYNAMIC - 1 WASH=OUT' UTILIZED IF DEEMED NECESSARY. og _ m CAPITAL ENTERPRISES 1 T.4 "il A k'3?';I, 'w • ZONED: C-1 - ,a�1 .ARE'A 1 a N "' USE: OFFICE BUILDING j .f1 - I 1 - - _ ¢ ny o UZ gy• 3� _ yam J --oi'., 1 ` no q -.1 y "... y I PAVING I24 3; - _'.r'. r._������►=�_^ f' I •PERA7ION' `7 __.,_.„ , SF YI ������ • 0' • / • ' • _,,,,„ _ ♦ ���� Bw599: �. r ,x L_E - 1� I ,1 1 11 \ , 1 , . ,. / I ,\ i \ f� :- _ � 1 WASHrRA,C , \,/ j \ . „ \ ,, \� / h•^_•K�♦\ TW60B0 _ ® I �i ` 1 \ \ \ ` •\\ \ \ -., , \ �/ o �� \ \ \��f '? +� -..r-A� RW 5590'. __ ''• i 1 ' 1 ` ` \,1. _ p OAK \ t1 y / ' 1 /' I ----.\----_,_ � OPERATIONS \',11 1^ % I`'`II 1 �.�` \1 \\ 1 \`\ •.\ — � '1 \�et0dnv��\ ;. S ,ao'� I i ���,�% )l \ III '�l 1 1': ' 4'. I 1 \_____,• l'' j r, // /z w )•' • ------ '�.` \ \\ \---�_ \ 11 �'8-P9? 2TOP fo r I• r'60;0 4°,� 1 f•••• I ,% _ • IIC. 1 I , \ ' \ //' I/ z z HE LRNOSCAPE 1 60 jf 1 oF'tHA (0 .ii....ra'a 1, I I �.'• 1 -\ 1 1 \ i 9"JAK i 1 ��_—i'r0�llll �[ �,.1: f N 1 1 \ 'I \ i I ! I + i zz ti �• I �, I ,: 10PO? P5'°i } \ • ] 1.1 / ' 1 I� �, I\ F. •1I 0 0 II /\ �/ �\ I psi,E 1/ 12•`00K !� r r�r'/jI j• r%/ LIMITS OF LAND I +• ����,•:.. I. 1•, \,',, '11.} ' i �' % _— z z \, \ rj i P�~ • 1 �. DISTURBANCE �/ �„ 1 = I. ) 1 I j / o o'o /� \` + �'+ 0'bO+�} j I �/ =0.88 ACRES / 1 < p, ' 1 \ '\,/ art,. - N e0501 CO 1 9 x18' CD'''k I' \I,` / �^\ 6W 50�01 / I --�_�\ ` \\ \ � � I'POP) Ia"uPC I�h,� 1 I �rrP) / ` `t t 1�:;1 1 VN>I N D `` '1 1 I \ \ I w , I \ \ I 124 INE \\ ` HI'ID 1 0i' I TMP 60E-3 } ,4' 1•' m n7 . 1 'I \ \ I o C 1 /° .,,y I CKW2. LLC / 11 1� G 1 / ,� 1 n—� 1v "v loPOP STAGING� / PP 1 ZONED: NMD \�� '� 1d�_ C_� ' 1 �� C� II �1: �, \I \ � M ��--� \ \ \ >\ I : , M `, .+3r I �{ ,I'1 USE: VACANT ��/ I +1. I 1.05 \Q \ '� r `\ ,\ , ti � ', 1 1.05 ACRES 1 1�� \ // �_' \ V 1 1.-.,- _ /� �r^e,� .ems V V A \ V 1{I t �� \ I + 1 �.� �� t � '1 , / - DESIGNED BY:JLF(VSMP) TMP 60E-2 �''• ''7"""'T'OYAL DRNNAGEI ARFP, .--^ ' J I I ....4. 1 ' , \ '1 \ \\ \ �— DRAWN BY: JLFNVN \ \ GEORGETOWN GREEN TO SILT FENCE= 0.88 AC \ 1 ° �� F ( 1 I \ \ \\ ZONED: R-6 \ \ LINEAL FOOTAGE OF SILT 1 I 'I\1 1 I ,l\'�■ 1 ,� i ��} 1 .1 '\ 1, \-- -- - CHECKED BY: JLT \ \ \ ` USE: RESIDENTIAL )) \ FENCE=530 LF I I 1 �1���>! >a1' \ a t1 • ` _ l \ — �-,� ySx op \ COMMON AREA f � /is I \ 6P p \ 12'°'P /�0'•7F (DOES N07 EXCEED ��II I ' oi\\\� , I t __Ij..,P 1� �` '1 - ` �__ @@ fpc �\ \ \ \ ��+ ALLOWABLE yvL ° o\ \ \ EX CHAINUN'R F 0' 0.25 ACRES PER 10.0 LFl) I ( ®I `I�i i �., 1[3�� "„� '_ 0• 'I `\ \ \ "/�; \ \'\\ o Pp' /1 iOLv� / 8'OA {® 81PI' 2a7'�P 11,I I�I'��`. {7•� I�`' ,.-BOx I • / UU�� \ \ ¢•J I J \' -l�' 1\ _ \ Jimmy L.Taggart \\ ~ �� ��� L J Q HENCHMAN( 'I ` \ \ 3"POP , 76"Pu �I .'I I I iRAFFLC ROx \ \ , R p S'1 I + `I O" �. / �J L EL VAiION=fi Id.]9 / I /- Lic•No. �. — tl + I / y, 2 J!}' 1 / \ '11111111� {ppi„0 1' f / �g \ �II 1111 1 ' e o' ` rONAL i! \ 20"'oP % \;' r .. 1.1 'I I ���\\'��� `////'�I /�111111111/ v' 1 / , ` 3g L� \ 1 / ' �-\\ i / .'L 1 F I 1 'I \\T,�� /`\/ 1411111/1111 " •t'' • 1 ` I „ , j \' 12 BC? 0 • 9 ,`z Pa 1 rTy9 11 `I/1 \\� \`\—j' ijII 1{i%yi�e%%4 y . 1 , , 1 . ill/ / / / i �f �� 'Ze.aK ,'7 f' /..L.,,,'N.,, 4,`\\\) �, a/ / L" .j'• .TO?LIGIi POLE I' \-------N , CL` I- v' i // / / / '� Ir ( •/ • -/ /! ''s♦\ourya i' `�\\\\\� \ / 0� r DUMPSITER 1 ;' ^r-� '�. /' 1 W / / r / / n / Or SC %®11 ����� �\ �\ /��,,./41115W ems` , W ¢ d /- / ` sq t / 1 • '' \.�� j PORTA-POTTY \ 1 N / \ co cc< / 1 / / / yi7/ 36'OAKX2 �.\IHF / "� 1� °^%iI �' \1 i �\// % -{•'J I , \ I'1 \ /� z } O / / / /, o'l1PL �, "pAK �♦� i ew i°•ai/��, c • Q = w z / / // % / /� / % \ '1 �.. � �: /By, \. / II��. }�'��� ` / Ill / z > / / /� / //// / /. ao' E%.I2 ACSA EASE!JENT ''1 r ♦��i,Hl�. 'y z.�'.:I�•� \ \\ 11 / // W a S m CC / / / /, / DB 440 Pc 30 a Ia'vRL; �, I `0 1.I `N/ ,/ '1 \ \ / /_�; ¢ 0_ i / / ,i / / ' ♦♦� rw609a� r,.;. '/I �1/ �� X / `�� \ _/ / Q o Z j / / r° r / / / \ \ _ $PILL ♦ ew we s; I / �'l,C/ L' �� j O • /' / / /�z , / 1 ONTAINMEN I I �♦♦ �a i ./j�I�O .,� /, ✓ i �/le i W o / / i 15 TMP 60-768 I • + t t'I(J Q' / / / / / // / MICHAEL&MELINDA - \ ram♦ { / ,\ i [---� / 0 U J / SPRINKEL I .• ! d /I Q sep\j / / i' i' ZONED: RA I . "♦', / //'.'-1):`I Qi H CC 0 /, // // / USE: RESIDENTIAL p ♦ / // `Q i I /- i/ . 47-4 ,,, / 14 , '. s', / / / ' ii / ( ,I4,1 �,♦\ /bvJ.p<�I �� / \ `\ .I -_`I%� �.-/ Q O r {{ h _ I /' I , I 3 / / j�\ j i \\_ \' /11 `; ,l .. , 1 I .,I i / / j \ _I / I �- i 'DATE OCTOBER 25,2019 I' / '�` ` SCALE N/A / /' 1 • .'' , �-� _ I I /�/ I \2,--- JOB• GTH .1 1 \ _ I ! • FILE 19.0//1�/25 / //' I I 'I't / \ SHEET: ` OF 3 PURPOSE VEHICLE FUELING AND MAINTENANCE ,„°ra, DISCHARGES OF SOAPS,DETERGENTS,SOLVENTS,AND SWPPP UPDATES \ WASH WATER FROM CONSTRUCTION ACTIVITIES SUCH AS w ✓Conduct regular maintenance in a dedicated area at is located to maxim¢,the The operators)shall update the SWPPP to mclutle: 0" 4VACSObO-54 o1 me Virginia Stonmrater Management Program (VSMP) Permit distance from storm drain Inlets,ditches,waterbomes or wetlands but no less than t,,01..1 _I.° r„st 11 CLEANUP OF STUCCO,PAINT,FORM RELEASE OILS,AND Regulations requires that Stormonter Pollution Prevention Plan(SWPPP)be developed 50 feet from Nose features. 101°eAS1 ' CURING COMPOUNDS ✓A record of dates when 1)major grading activities occur,2)construction eased. V co o for all regulated land disturbing activities.The SWPPP must include,approved but not be limited .c ....10194.trer..l -S MK _ I to, an approved erosion and sediment control plan, an stonmtater If fueling s conducted at a dedicated area,the location must be located to�"pion aMcl _ m,c,tea __ Icanes distance from storm dam inters,, hesl cation r�es or wetlands but == temporarily or permanently cease on a portion of the site,and 3)stabilization Q Oro �_ management plan,and this Pollution Prevention Plan(PPP)for regulated land maxi = ✓Washing activities associated wdh conedrudion activities other than vehmle and measures are iodated, CI) Q m ,w', n no Tess man 50 feet horn those features = - �� disturbing TMactDLes,and a description of any additional control measures necessary a r I_T T u _ i i§.; i equipment wahing,such as dean up of stump,paint,form release ois,and curing ✓ D umerr.hon of modifications and revisions to me SWPPP; t%) o m address a TMDL as appicable. I The dedicated areas must be destined a eliminate the discharge of spilled and .n.w.,x - srmm" ✓mmpoun ds are to be conducted m a dedicated area ✓ havereached final stabilization where no further SWPPP or inspection Q p Z leaked fuels and chemicals from vehicle fueling and maintenance actvldes by s MP.) The dedicated area must be located to maximize the distance from storm drain ��yy The plan for implementing pollution prevention measures during construction activities providing secondary containment(spill bents,decks,spill containment paints, ro'on usx a s since avers inlets,ditches,waterbodies or wetlands but roc less than 50 Feet from muse featuresI All properties that are no longer under the legal control of the operator and the dates �q O m developed on this sheet must be implemented and updated as necessary. Any PPP providing cover where appropriate,and having spill kits readily available) IOQm m EM •nee(99 t __-------- Separations of less man 50 feet may be approved by the Environmental Inspector on which the operator no longer had legal control over each property,and W O a en requirements not included on this sheet must be incorporated into the SWPPP required Each fatuity must have appropnate signage to Inform users where the dedicated ®Je ® 4l rem lie.✓The dedicated areas must be designed to prevent the discharge of soaps, ✓The date, volume, and coriedivelpreventalive actions bnplemente0 for any J 2 by 4VAC50S0-54 that must be developed before land disturbance commences. This area(s)are located �' H :K ' ®,-Tr�=� detergents,solvents,and wash water prohlbdcd discharge Z PPP identifies potential sources of pollutants that may reasonable be expected to affect - k _ The oaetatorts)shall update me SWPPP no Ater flan seven[7)days following any of (� -j y the quality dormwater discharges from the cornehlrptlen site(loom on-and off-site Shown on ORES B T. /I II] Shown on the situations identified above. .M_�_..,1 m activities)and describes control measures that will be used to minimize pollutants in Date Plan Location pilled/cafedArea(s) 1 Ili �� y _- _ r Date Plan lymton(s)of�ted Areas) W LL Z 4 sarmwater discharges from the construction site. Sheet OM 1 --- — 1 1.,�-, Shcetigs) - • OPERATOR INSPECTIONS V] O j A roved luram� ® s_ APPxoved - - - - . . - Q¢ w OTHER REFERENCED PLANS poem r^_-. i —.._�_..�-_�_��. s°sin PArrc'°s .sMc(mea io w.none° - L -=-rroM m aai Pan - - - _ - The apaatogs)identified below shad provide Icr inspections a me pemndted land- p� a m F`> o SWPPP requirements may be fulfilled by incorporating,by reference,other plans All REVISIONS TO LOCATIONS Nam. • REVISIONS TO LOCATIONS disturbing activities by the qualified personnel identified below. The inspections will ore ¢ conducted 19 (select one the following options): ^ Shown On l�•-1 r-J plans incorporated ebye reference become for Discharges under the VSMP Permit Shown on O erator's CONCRETE WASHOUT AREA CONCRETE WASHOUT AREA Date Plan Location(s)of Dedicated Areas) Operator(s) _ _ _ _ _ _ - _ Toy Regulations and General Permit VAR10 for Drencees of Slormwater from Date Plan Location of DedicatedArea(s) Intals ABOVE-GRADE CONTAINMENT AREA W/STRAW BALES BELOW-GRADE CONTAINMENT AREA Sheet di,$) Inca's ❑"at least once every fduf(4)business days;or .I r0 mC Construction Activities. If a plan incorporated by reference does not contain all of the Sheet les) - required elements of the PPP,the operator must develop me missing elements and - - _.p am I D at least once every five(5)business days and no later than 48 Rouen-_.following 0 o 0 y any-measurable storm event �' include them in the SWPPP. B sit mwMsan u �nm^9M vie r..nf ._.._-` __ _ --" .> _ - ( "'A ` t Where areas are in a stabilized condNon or runoff S unlikely due to winter conditions. -------_ Independent Plans Date / i °° '- awn - the inspection frequency may be reduced to once every 30 days while these conditions Incorporated by Reference Approved ' . ir �\, - exist Otherwise,the operator's)Shan resume Ore regular inspection frequency ca'd°a identified above. Sarmwater Management Plans(Regional or Master) _ I If mobile fueling wall be used,the fueling must be done In an area that located a / I% �� ✓ Spit Prevention.Control,and Countermeasure Plans _ - maximize me distance from storm drain inlets,d'Rcnes,waterbodies or wetlands but /j The dedcated area mug be covered(e g,plastic sdeehng,temporary root etc)to prevent canted with must betco The operator(s)shall provide for inspections of the permitted land-disturbing activity to no less man 50 feat from mole features ensure implementation and continued maintenance of all requirements of me SO kits must be readdy available at MI mobile reefing locations. ✓The contaminated wastewater from the dedicated area must be collected for Off-Sole Stankpile WA /`= ..w averStomiwatef Pollution Prevention Pan(Erosion and Sediment Control Pan,S[ormvrater OfSRe Barrow Area WA _ I Onsde storage tanks must have a means of secondary containment(spill berms, MP..10019.0 19 LW fd V. disposal by awaste hauler or discharged to the sanitary sewer. Management Plan,Pollution Prevention Plan,TMDL requirements,etc.). - = decks,spill containment pallets,etc.)and must be covered where approprate. ma.�me"^v""""•1°c +e In situations where these pollutants are or could be generated at lom'Jons other than o 1911.905 44914 BE Ma. _ at the designated area(e.g.,conaete pours,binding washing,etc.),cover(e.g., Records of the required inspections must be maintained and induded in the SWPPP - - - - ✓All vehicles on me must be monitored for leaks and receive regular preventive plastic sheeting,temporary oaf etc.)must be Provided to prevent contact with binder. The qualified personnel are encouraged to use the Operator Inspection form ` - - - maintenance to reduce the chance of leakage. I m. °L'F°'' I stnrnx atef and the contaminated vrasiee,ater from the activity must be collected for provided in the SWPPP binder to document the required inspections d inspections are uxA 311.1 at Wen Ia. disposal by a waste hauler or discharge]to the sanitary sewer. conducted once every five(5)business days and no later than 48 hays following any o ""Im...c amsa,r, 11`II.1 1 I 1 .1-1:1,11 I. ' measureable storm event the location of the rain gauge used to determine the amount olr of ran must be included In the SWPPP and documented in the inspection report DISCHARGE FROM STORAGE,HANDLING,AND DISPOSAL °" „4-� t vri; ?• .� „ POTENTIAL POLLUTANT SOURCES OF CONSTRUCTION PRODUCTS.MATERIALS,AND WASTE w. T EMCE _ LOCALE ON m�Re DOWNHILL SIDE DISCHARGES OF HAZARDOUS,TOXIC, ACKNOWLEDGEMENTS The following sources of potential pollutants must be addressed a me Pollution ,/ WASH RACK OF PORTABLE Prevention Plan. Various controls and/or measures designed to prevent and/or Storagea constructionproducts,materials,and waste is to be conducted SEDIMENT CONTAINMENT AREA TOILET AND SANITARY WASTE minimize pollutants in sc site. er discharges from the project sae must be applied a dedicated areas the sources found on the sine.Additional information concerning the following controls ✓The dedicated area must be located to maximize the distance from stone drain ✓Storage and aspasal of hazardous,toxic and sanitary wastes am a be conducted n 1 certify under penally of raw that the qualified personnel identified below: and/or measures may be found in the SWPPP. Deviations from the location criteria inlets,ditches,wate�es or wetlands but no less than 50 feet horn those featuresN may be approved by the Albemarle CountyInspector. Separations a less than 50 feel may be approved by the Environmental Inspector. Theeiwted areas. a has been designated by the Operator to conduct inspections oldie O z y D ✓ SOLID WASTE COLLECTION CONTAINMENT AREA + ✓ dedicated areas must he located a rrmiint¢e the distance from storm dais permitted sde: The dedicated areas must be designed to rtnnimim the discharge of pollutants from m tiles,ditches,wmerbodies or wetlands but no less than 50 feet front those features. b. is knowledgeable in the principles and practices of erosion and storage,hardomd,and disposal of as don products,materials and wastes LEAKS,SPILLS,AND OTHER RELEASES including(ghesivbuilding products such as asphalt sealants,copper flashing,roofing ro• Separations of less than 50 feet may be approved by the Environmental Inspector sediment control and stonmwater management NN materials,adhesives,concrete admixtures;(ii)pesticides,herbicides,insecticides. ✓The dedicated areas must be designed to prevent the dschage of hazardous,toxic c. possesses the skills to assess conditions at the permitted site for the • W W ✓The operator(s)shag ensure procedures are in place to prevent and respond to MI ferhhzea,and landscape materiaso and(S)construction and domestic wastes such _ _ f and sanitary waste by avoiding contact with precipitation Operator(s)that coubl impact sto mvatef quafty and quantdy, zo leaks,spills and other releases of pollutants, as packaging materials,scrap mr5irodlon materials,masonry products,timber, - a, STD. ✓had,featly must have appropriate sgnage to inform users where the dedicated d. will assess the effectiveness of any erosion and sediment control =f f P Po pipe ram,plastim,Styrofoam,concrete and other trash or build Iran o ter PORTABLE area(s)are located- measures or slormwater management acddies selected to control the g o 0 and electhcal acid rig )` ,a1 ✓The operator's)shall ensure rag leaks,spills and other releases of pollutant are products..a_ TOILET Sarrliwatef discharges from the permitted sole;and contained and clowned immediately upon discovery. Any contaminated materials Shown on'Locabon(s)of Dedicated Area(a)for swage and disposal of' e. wig conduct inspections in accordance with the frequency noted above z z are to be disposed accordance with federal,state,and/or local requirements I Each faddy must have appropnate sgage to inform users whne the defecated posequireme Date Plan i hazardous and toxic wastes I in the OPERATOR INSPECTIONS section of this sheet 0 0 I The operator(s)shall ensure spill containment kits containing appropnate materials areas)are boated ,_., owed Sheet_s _ _ _ (e.g,absorbent material and pads,brooms,gloves,sand,ere)are available at ONT1On Locafion(s)of DedicatedArea(s)for storage of construction Approved Pp -• QUALIFIED PERSONNEL appropnate locations,Including,but not Ilmrted to designated areas for vehicle and Date Pan Sheet —9, 9 products and materials FUELING AREA �� NgRe • (Ptbe) I: egmpmem maintenance;vehicle and equipment fueling;storage and disposal of tt(sl REVISIONS TO LOCATIONS - - _ ,,, construction materials,products,and waste;and swage and tlsDosal of hazardous APProvetl( - - - - - "- - BELOW-GRADE CONTAINMENT AREA i -- ------ o o _ _ _ shown on - andtoxicnaterals;and Sanitary waste Noddies. Plan j - -. _ - - - y� Date Plan Location(s)o/Dedicated Amok)for cootie Opeamr(s)i i Phone .- ' . m-- ✓The locations of the spit containment kits are identified as described below. REVISIONS TO LOCATIONS io me n,usnc U. Sheet••s I and disposal of hazardous and toxic wastes I Instals . Sham on Dale I Plan Smtreet_Lora0°n(s)of DedrcatedArea(s)for storage Operator(s) r r Mn. 00%°e •• - - - I Adddana)indomation is located in Tab 6 of SWPPP Binder, If z `v Date Plan Sheet Location I 0(s) of construction products and natenals Initiate I r I [ �s) -- _ Avm rvtvxe AREA -L. `^ __..�.,- . ___._,_ _.__I DESIGNED BY:JLF(VSMP) As the O aster's)or Delegated AimDRAWN BY: JLFNVN -Approved • - - - - _ M - pe Authority,Ihwe understand that prior to initiating land Plan _ - - - -"� - �� disturbance,the potential pollutant sources,appropriate control measures and all "CHECKED BY: JLT <- - REVISIONS TO LOCATIONS---- - I - • roc nor DIVERSION cob ¢one 5o1e responsible parties(operator,qualified inspection personnel,contactors,etc.)required as e condition of the General Construction Permit(GCP)and the Sanrnvater Pollution Shown on Operator(s) I - - . v rs A unuu(ns.l Sham on' Prevention Ran(SWPPP)must be identified. I also understand this infomration must A1,pLTB Op p✓ Date Plan Sheet Location Initials - < ® .--.,, s Date Plan Location(s)of Dedicated Aeea()ar portable toilets be updated as necessary throughout all phases of corstnrWan until the GCP is do �`•�.r, Sheet e[s) temninated. Cs) - .',.i_:.`s"Ff`.J�r''.:.mac,;"`.:' _ _ _ • Shown on Location(s)of DedeatedArea(s)for waste from k,°.,,1; ;.'i;,:?,+• Approve0 _ Date Plan Sheet construction products and materials T ® ' 'r ;+:;:'.,!, y�;v>�� Pan - - - -• • - Furthermore, - - 1' y� y Yqs) // Approved _ - •v :PAVED ti¢�c�u+rw:?�;A�; I/we ceNfy under penalty of law that I/we have read and undersand all requirements of - Plan _ - - • - ® ' REVISIONS TO LOCATIONS the SWPPP(erosion and sediment control plan,stormwater management plan,pollution Jimmy L.Taggart - - _ Shown on i prevention pan,TMDL provisions,administrative requirements,eta.)and GCP and that tic."o. y. REVISIONS TO LOCATIONS 1 V/ -\' ' Location(s)a Dedicated Area(a)for portable Opeatogs) 22aat o Date Pan the information herein is,to the best of my knowledge and belief,true,accurate,and o ,fw toilets Initials Quality of leaks,spills, Shown on oar s IN !!` .. Shed e(s) complete. I am aware that there are significant penaNes for submitting false 4'erox t quo I The operator(s)shall notify the Department of Environmental O typLocation s of Dedcaed Area(s)for waste Operator(s) - A and other releases that discharge to or have the potential a discharge a surface Date Plan Sheet' () I m uL vtAsne iron .m,from construction products and materials Indials hoe ci emnu'' _ information,including possibility of fine or imprisonment knowing violations. wales immetletely upon discovery of the discharge but m no case oar than 24 - �_-_,�YHsI-__ _ roe or saes - Y I Owe understand that I/we are ultimately responsible for compliance wrth all conditions - aRerthediscovery. - and requirements of the SWPPP and GCP and for ensuring all contactors and ✓The operator(s)shall natty the Department of Environmental Quality(DEO)of leaks, - - DISCHARGES FROM CONCRETE RELATED subcontractors on the permitted site are aware of the mcoitiars and requirements of spills,and Omer releases that discharge a or have me potential a discharge to - - WASH ACTIVITIES - - the SWPPP and GCP. z surface waters immediately upon discovery of hethe discharge but in e no case later than dove shag comply with all conditions and requirements of the SWPPP and shall at all 24 after the discovery. Written notice of the discharge must be sent to DEO and • ✓Consult with local waste management authonhes or private firms about the Hen rico CountyDepartment of Public Works within five(5)days s of the discovery. 9e limes properly operate and Nair u maintain all measures and control (and related �1 ( Y ry• Concrete trucks site not allowed to wash cut or dischargeea( surplus concrete In a drum requirements for deposing of hazardous materials and/or soils that may be appurtenances)which are installed or used to achieve compliance with the condfloes of V Virginia Department of Environmental I Albemarle County ✓Follow all federal,state,and local requirements that apply to the use,handling and wash water on except in a dedicated area(a)that is located to prevent contaminated wdh hazardous materials. the GCP. Proper epradon and maintenance also includes adequate funding and I- Quality Community Development disposal of pesticides,herbicides,and fertilizers. discharge to storm drain Inlets,ddches,watenbodies or wetlands but no less than 50 ✓Never remove the original product Jabal from the container. Follow the adequate stating Z J NEED ADDRESS Engineering Department ✓Keep chemicals on-site in small quantities an in closed,well marked containers. feet from those features. manufacturers recommended method of disposal al (804)786-3998(phone) 401 McIntire Road ✓Clean up solid waste,including building materials,garbage,and debris on a daily ✓ Each fadfity must have a stabiliized access to prevent mud tack(ng into the sheet. ✓Schedule:periodic punt In of portable toilets and d' a of Uwe shall eke all reasonable steps to minimize or prevent any discharge m violation of (804)786-1798(fax) Chadodes2lle,VA 22007 basis and deposit into covered tlumpsters that are periodically emptied. ✓Dispose Pe pumping P dispose the SWPPP and/or GCP. (800)468-8892(outside normal working (434)298-5832 Each facility must have appropriate siting,to inform users where the dedicated pose of all solid waste at an authorized disposal site. LB hours) ✓Schedule waste collection to prevent exceeding the capacity of posit,containers. areas)are located. I/we understand that if it determined by the Department of Environmental OualW(DEO) (D CC z co Adddonal containers may be necessarydepending on the phase of construction m consultation with me Sate Water Control Board at any time that stormwater J_ P 9 P SWPPP MODIFICATIONS AND REVISIONS < discharges are cousin have reasonable potential to muse or coninbme to and (i g.,se of all so eta.) Shown on g g, p Z >- ¢ Q ✓Dispose of all solid waste at an author¢etl disposal site. Date Plan Location of Dedicated Area(s) excursion above any applicable water quaiy mstandard,taction the d re may,in consultation > The operator(s)shall ensure the SWPPP s modified and/or rewsed to reflectQ - EQUIPMENT)VEHICLE WASHING ✓Ensure mat containers have lids or are otherwise protected horn exposure to Sheet It(s)i wash me Administrator,lake appropnate enforcement action and require: = w Approved _I - _ _ •- _ ♦ Changes In quaified personnel;delegated amhor0ies or other personnel required as a Modification of control measures to adequately address water qml a od precipitation. Pan - __ RY z ✓Washbg must be conducted Ina dedicated area that is located to maximize the - - - a condrtmn of the General Construction Permit; concerns; p w op distance from storm drain inlets,dddtes,vraterbodies a wetlands but no less than DISCHARGES FROM OTHER POTENTIAL POLLUTANT REVISIONS TO LOCATIONS ✓ •Changes in site conditions, b Subm'ssion of valid and verifiable data and Information that are H 0- a 50 feet from those features. SOURCES ✓ Changes in the design,construction,operation,or maintenance of the construction representative of ambient conditions and indicate that the receiving water is site that affect the potential for discharges of pollutants that are not addressed in the attaining water quality standards;or < O o O I- I All wash water used in vehicle wheel washing must be directed to a sediment Shown onI— Z Z basin/trap. ✓Discharges from other pollutant sources(e.g.,wear Inc flushing,storm sewer Date Plan I Location of Dedrmtedgrea(s) Opeater's normal implementation of the plan;and c Cessation of discharges a pollutants horn construction activity and submd an Z � I All vehiainm a washing acivities other than wheel washingmust have secondaryPushing,above ground storage tanks,dc)not mentioned elsewhere must be I Sheet#(s)' Inifias I Ineffective control measures identified during inspections o investigations individual permit application according to 4VAC25-870-410. containment addressed. - conducted by the operator's qualified personnel or local,state or federal offices. w o d ✓ Each raality mud have appropnate ssgnage to inform users where the dedicated Other Potential Pollutant Sources I Locations)of Potential Pollutant Sources - Modifications/revisions to the SWPPP shall include additional or modified control IIJJ area(s)are located. - - _ - • _ measures to address the identsfied deficlancies. OPERATOR(S)/DELEGATED AUTHORITY j I- O Shown on • I . i • Name(print) Signature Date r Ac[rvty Location of Water Source - ' If me necessary modlficatlons/revsions require approval by the Administrator or DEO, - _ - Q w Dedicated Area(s) Sheet s Location I ✓ Facilities must be cleaned,en new facilities constructed,once the washout areas the modficatiorslrevisions must be implemented no later than seven(7)calendar days • • e(s) - following approval. CD Wheel Wash I _ - _ . - two-thids(2!3)full. - CO Other Wash [ If the necessary modifications/revisions do not require approval by the Atlminlstrator, Areas I" - - - dsfi the mocatons/revislos must be implemented prior to the next anticipated storm - . - -- event or as soon as practicable. - REVISIONS TO LOCATIONS Ad di ground oil storage tanks with a storage copacrty exceeding 1,320 gallons and ditional contact information can be found in the SWPPP Binder. Shown on have a reasonable expectation of a discharge into or upon Waters of the United I Location ofPlan Water Source Operator's Sates are required to have a Spill Prevention Control and Counameasure(SPCC) DATE OCTOBER 25.2D19 ActivityDedicated Area(s) Sheet Ns) Location Initials Plan. I . ✓The discharge of contaminated flush water and material removed during flushing SCALE N/A operations must be collected and disposed of in accordance with appropriate JOB GTH I federal.state,and local requirements. _19 0125 ,\ / SHEET 3 OF 3 APPX B- Copy of Construction General Permit 27 F7 COMMONWEALTH of VIRGINIA DEPARTMENT OF ENVIRONMENTAL QUALITY General Permit No.: VAR10 Effective Date: July 1, 2019 Expiration Date: June 30, 2024 GENERAL VPDES PERMIT FOR DISCHARGES OF STORMWATER FROM CONSTRUCTION ACTIVITIES AUTHORIZATION TO DISCHARGE UNDER THE VIRGINIA STORMWATER MANAGEMENT PROGRAM AND THE VIRGINIA STORMWATER MANAGEMENT ACT In compliance with the provisions of the Clean Water Act, as amended, and pursuant to the Virginia Stormwater Management Act and regulations adopted pursuant thereto, operators of construction activities are authorized to discharge to surface waters within the boundaries of the Commonwealth of Virginia, except those specifically named in State Water Control Board regulations that prohibit such discharges. The authorized discharge shall be in accordance with the registration statement filed with the Department of Environmental Quality, this cover page, Part I - Discharge Authorization and Special Conditions, Part II - Stormwater Pollution Prevention Plan, and Part III - Conditions Applicable to All VPDES Permits as set forth in this general permit. Construction General Permit Effective July 1, 2019 Page 2 of 26 PART I DISCHARGE AUTHORIZATION AND SPECIAL CONDITIONS A. Coverage under this general permit. 1. During the period beginning with the date of coverage under this general permit and lasting until the general permit's expiration date, the operator is authorized to discharge stormwater from construction activities. 2. This general permit also authorizes stormwater discharges from support activities (e.g., concrete or asphalt batch plants, equipment staging yards, material storage areas, excavated material disposal areas, borrow areas) located on-site or off-site provided that: a. The support activity is directly related to the construction activity that is required to have general permit coverage for discharges of stormwater from construction activities; b. The support activity is not a commercial operation, nor does it serve multiple unrelated construction activities by different operators; c. The support activity does not operate beyond the completion of the last construction activity it supports; d. The support activity is identified in the registration statement at the time of general permit coverage; e. Appropriate control measures are identified in a stormwater pollution prevention plan and implemented to address the discharges from the support activity areas; and f. All applicable state, federal, and local approvals are obtained for the support activity. B. Limitations on coverage. 1. Post-construction discharges. This general permit does not authorize stormwater discharges that originate from the site after construction activities have been completed and the site, including any support activity sites covered under the general permit registration, has undergone final stabilization. Post-construction industrial stormwater discharges may need to be covered by a separate VPDES permit. 2. Discharges mixed with nonstormwater.This general permit does not authorize discharges that are mixed with sources of nonstormwater, other than those discharges that are identified in Part I E (Authorized nonstormwater discharges) and are in compliance with this general permit. 3. Discharges covered by another state permit. This general permit does not authorize discharges of stormwater from construction activities that have been covered under an individual permit or required to obtain coverage under an alternative general permit. Page 3 of 26 4. Impaired waters and total maximum daily load (TMDL) limitation. a. Nutrient and sediment impaired waters. Discharges of stormwater from construction activities to surface waters identified as impaired in the 2016 § 305(b)/303(d) Water Quality Assessment Integrated Report or for which a TMDL wasteload allocation has been established and approved prior to the term of this general permit for (i) sediment or a sediment-related parameter (i.e., total suspended solids or turbidity) or (ii) nutrients (i.e., nitrogen or phosphorus) are not eligible for coverage under this general permit unless the operator develops, implements, and maintains a stormwater pollution prevention plan (SWPPP) in accordance with Part II B 5 of this permit that minimizes the pollutants of concern and, when applicable, is consistent with the assumptions and requirements of the approved TMDL wasteload allocations and implements an inspection frequency consistent with Part II G 2 a. b. Polychlorinated biphenyl (PCB) impaired waters. Discharges of stormwater from construction activities that include the demolition of any structure with at least 10,000 square feet of floor space built or renovated before January 1, 1980, to surface waters identified as impaired in the 2016 § 305(b)/303(d) Water Quality Assessment Integrated Report or for which a TMDL wasteload allocation has been established and approved prior to the term of this general permit for PCB are not eligible for coverage under this general permit unless the operator develops, implements, and maintains a SWPPP in accordance with Part II B 6 of this permit that minimizes the pollutants of concern and, when applicable, is consistent with the assumptions and requirements of the approved TMDL wasteload allocations, and implements an inspection frequency consistent with Part II G 2 a. 5. Exceptional waters limitation. Discharges of stormwater from construction activities not previously covered under the general permit effective on July 1, 2014, to exceptional waters identified in 9VAC25-260-30 A 3 c are not eligible for coverage under this general permit unless the operator develops, implements, and maintains a SWPPP in accordance with Part II B 7 of this permit and implements an inspection frequency consistent with Part II G 2 a. 6. There shall be no discharge of floating solids or visible foam in other than trace amounts. C. Commingled discharges. Discharges authorized by this general permit may be commingled with other sources of stormwater that are not required to be covered under a state permit, so long as the commingled discharge is in compliance with this general permit. Discharges authorized by a separate state or VPDES permit may be commingled with discharges authorized by this general permit so long as all such discharges comply with all applicable state and VPDES permit requirements. D. Prohibition of nonstormwater discharges. Except as provided in Parts I A 2, I C, and I E, all discharges covered by this general permit shall be composed entirely of stormwater associated with construction activities. All other discharges including the following are prohibited: 1. Wastewater from washout of concrete; 2. Wastewater from the washout and cleanout of stucco, paint, form release oils, curing compounds, and other construction materials; Page 4 of 26 3. Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance; 4. Oils, toxic substances, or hazardous substances from spills or other releases; and 5. Soaps, solvents, or detergents used in equipment and vehicle washing. E. Authorized nonstormwater discharges. The following nonstormwater discharges from construction activities are authorized by this general permit when discharged in compliance with this general permit: 1. Discharges from firefighting activities; 2. Fire hydrant flushings; 3. Waters used to wash vehicles or equipment where soaps, solvents, or detergents have not been used and the wash water has been filtered, settled, or similarly treated prior to discharge; 4. Water used to control dust that has been filtered, settled, or similarly treated prior to discharge; 5. Potable water sources, including uncontaminated waterline flushings, managed in a manner to avoid an instream impact; 6. Routine external building wash down where soaps, solvents or detergents have not been used and the wash water has been filtered, settled, or similarly treated prior to discharge; 7. Pavement wash waters where spills or leaks of toxic or hazardous materials have not occurred (or where all spilled or leaked material has been removed prior to washing); where soaps, solvents, or detergents have not been used; and where the wash water has been filtered, settled, or similarly treated prior to discharge; 8. Uncontaminated air conditioning or compressor condensate; 9. Uncontaminated ground water or spring water; 10. Foundation or footing drains where flows are not contaminated with process materials such as solvents; 11. Uncontaminated excavation dewatering, including dewatering of trenches and excavations that have been filtered, settled, or similarly treated prior to discharge; and 12. Landscape irrigation. F. Termination of general permit coverage. 1. The operator of the construction activity shall submit a notice of termination in accordance with 9VAC25-880-60, unless a registration statement was not required to be submitted in accordance with 9VAC25-880-50 A 1 c or A 2 b for single-family detached residential structures,to the VSMP authority after one or more of the following conditions have been met: Page 5of26 a. Necessary permanent control measures included in the SWPPP for the site are in place and functioning effectively and final stabilization has been achieved on all portions of the site for which the operator has operational control. When applicable, long term responsibility and maintenance requirements for permanent control measures shall be recorded in the local land records prior to the submission of a complete and accurate notice of termination and the construction record drawing prepared; b. Another operator has assumed control over all areas of the site that have not been finally stabilized and obtained coverage for the ongoing discharge; c. Coverage under an alternative VPDES or state permit has been obtained; or d. For individual lots in residential construction only, final stabilization as defined in 9VAC25- 880-1 has been completed, including providing written notification to the homeowner and incorporating a copy of the notification and signed certification statement into the SWPPP, and the residence has been transferred to the homeowner. 2. The notice of termination shall be submitted no later than 30 days after one of the above conditions in subdivision 1 of this subsection is met. 3. Termination of authorization to discharge for the conditions set forth in subdivision 1 a of this subsection shall be effective upon notification from the department that the provisions of subdivision 1 a of this subsection have been met or 60 days after submittal of a complete and accurate notice of termination in accordance with 9VAC25-880-60 C, whichever occurs first. 4. Authorization to discharge terminates at midnight on the date that the notice of termination is submitted for the conditions set forth in subdivisions 1 b through 1 d of this subsection unless otherwise notified by the VSMP authority or department. 5. The notice of termination shall be signed in accordance with Part III K of this general permit. G. Water quality protection. 1. The operator shall select, install, implement, and maintain control measures as identified in the SWPPP at the construction site that minimize pollutants in the discharge as necessary to ensure that the operator's discharge does not cause or contribute to an excursion above any applicable water quality standard. 2. If it is determined by the department that the operator's discharges are causing, have reasonable potential to cause, or are contributing to an excursion above any applicable water quality standard, the department, in consultation with the VSMP authority, may take appropriate enforcement action and require the operator to: a. Modify or implement additional control measures in accordance with Part II C to adequately address the identified water quality concerns; b. Submit valid and verifiable data and information that are representative of ambient conditions and indicate that the receiving water is attaining water quality standards; or Page 6 of 26 c. Submit an individual permit application in accordance with 9VAC25-870-410 B 3. All written responses required under this chapter shall include a signed certification consistent with Part III K. PART II STORMWATER POLLUTION PREVENTION PLAN A. Stormwater pollution prevent plan. 1. A stormwater pollution prevention plan (SWPPP) shall be developed prior to the submission of a registration statement and implemented for the construction activity, including any support activity, covered by this general permit. SWPPPs shall be prepared in accordance with good engineering practices. Construction activities that are part of a larger common plan of development or sale and disturb less than one acre may utilize a SWPPP template provided by the department and need not provide a separate stormwater management plan if one has been prepared and implemented for the larger common plan of development or sale. 2. The SWPPP requirements of this general permit may be fulfilled by incorporating by reference other plans such as a spill prevention control and countermeasure (SPCC) plan developed for the site under § 311 of the federal Clean Water Act or best management practices (BMP) programs otherwise required for the facility provided that the incorporated plan meets or exceeds the SWPPP requirements of Part II B. All plans incorporated by reference into the SWPPP become enforceable under this general permit. If a plan incorporated by reference does not contain all of the required elements of the SWPPP, the operator shall develop the missing elements and include them in the SWPPP. 3. Any operator that was authorized to discharge under the general permit effective July 1, 2014, and that intends to continue coverage under this general permit, shall update its stormwater pollution prevention plan to comply with the requirements of this general permit no later than 60 days after the date of coverage under this general permit. B. Contents. The SWPPP shall include the following items: 1. General information. a. A signed copy of the registration statement, if required, for coverage under the general VPDES permit for discharges of stormwater from construction activities; b. Upon receipt, a copy of the notice of coverage under the general VPDES permit for discharges of stormwater from construction activities (i.e., notice of coverage letter); c. Upon receipt, a copy of the general VPDES permit for discharges of stormwater from construction activities; d. A narrative description of the nature of the construction activity, including the function of the project (e.g., low density residential, shopping mall, highway, etc.); e. A legible site plan identifying: Page 7 of 26 (1) Directions of stormwater flow and approximate slopes anticipated after major grading activities; (2) Limits of land disturbance including steep slopes and natural buffers around surface waters that will not be disturbed; (3) Locations of major structural and nonstructural control measures, including sediment basins and traps, perimeter dikes, sediment barriers, and other measures intended to filter, settle, or similarly treat sediment, that will be installed between disturbed areas and the undisturbed vegetated areas in order to increase sediment removal and maximize stormwater infiltration; (4) Locations of surface waters; (5) Locations where concentrated stormwater is discharged; (6) Locations of any support activities, including (i) areas where equipment and vehicle washing, wheel wash water, and other wash water is to occur; (ii) storage areas for chemicals such as acids,fuels, fertilizers, and other lawn care chemicals; (iii) concrete wash out areas; (iv) vehicle fueling and maintenance areas; (v) sanitary waste facilities, including those temporarily placed on the construction site; and (vi) construction waste storage; and (7) When applicable,the location of the on-site rain gauge or the methodology established in consultation with the VSMP authority used to identify measurable storm events for inspection as allowed by Part II G 2 a (1) (ii) or Part II G 2 b (2). 2. Erosion and sediment control plan. a. An erosion and sediment control plan designed and approved in accordance with the Virginia Erosion and Sediment Control Regulations (9VAC25-840), an "agreement in lieu of a plan" as defined in 9VAC25-840-10 from the VESCP authority, or an erosion and sediment control plan prepared in accordance with annual standards and specifications approved by the department. b. All erosion and sediment control plans shall include a statement describing the maintenance responsibilities required for the erosion and sediment controls used. c. An approved erosion and sediment control plan, "agreement in lieu of a plan," or erosion and sediment control plan prepared in accordance with department-approved annual standards and specifications, implemented to: (1) Control the volume and velocity of stormwater runoff within the site to minimize soil erosion; (2) Control stormwater discharges, including peak flow rates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and stream bank erosion; Page 8 of 26 (3) Minimize the amount of soil exposed during the construction activity; (4) Minimize the disturbance of steep slopes; (5) Minimize sediment discharges from the site in a manner that addresses (i)the amount, frequency, intensity, and duration of precipitation; (ii)the nature of resulting stormwater runoff; and (iii) soil characteristics, including the range of soil particle sizes present on the site; (6) Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal, and maximize stormwater infiltration, unless infeasible; (7) Minimize soil compaction and, unless infeasible, preserve topsoil; (8) Ensure initiation of stabilization activities, as defined in 9VAC25-880-1, of disturbed areas immediately whenever any clearing, grading, excavating, or other land- disturbing activities have permanently ceased on any portion of the site, or temporarily ceased on any portion of the site and will not resume for a period exceeding 14 days; and (9) Utilize outlet structures that withdraw stormwater from the surface (i.e., above the permanent pool or wet storage water surface elevation), unless infeasible, when discharging from sediment basins or sediment traps. 3. Stormwater management plan. a. Except for those projects identified in Part II B 3 b, a stormwater management plan approved by the VSMP authority as authorized under the Virginia Stormwater Management Program (VSMP) Regulation (9VAC25-870), or an "agreement in lieu of a stormwater management plan" as defined in 9VAC25-870-10 from the VSMP authority, or a stormwater management plan prepared in accordance with annual standards and specifications approved by the department. b. For any operator meeting the conditions of 9VAC25-870-47 B of the VSMP regulation, an approved stormwater management plan is not required. In lieu of an approved stormwater management plan, the SWPPP shall include a description of, and all necessary calculations supporting, all post-construction stormwater management measures that will be installed prior to the completion of the construction process to control pollutants in stormwater discharges after construction operations have been completed. Structural measures should be placed on upland soils to the degree possible. Such measures must be designed and installed in accordance with applicable VESCP authority, VSMP authority, state, and federal requirements, and any necessary permits must be obtained. 4. Pollution prevention plan. A pollution prevention plan that addresses potential pollutant- generating activities that may reasonably be expected to affect the quality of stormwater discharges from the construction activity, including any support activity. The pollution prevention plan shall: a. Identify the potential pollutant-generating activities and the pollutant that is expected to be exposed to stormwater; Page 9 of 26 b. Describe the location where the potential pollutant-generating activities will occur, or if identified on the site plan, reference the site plan; c. Identify all nonstormwater discharges, as authorized in Part I E of this general permit, that are or will be commingled with stormwater discharges from the construction activity, including any applicable support activity; d. Identify the person responsible for implementing the pollution prevention practice or practices for each pollutant-generating activity (if other than the person listed as the qualified personnel); e. Describe the pollution prevention practices and procedures that will be implemented to: (1) Prevent and respond to leaks, spills, and other releases including (i) procedures for expeditiously stopping, containing, and cleaning up spills, leaks, and other releases; and (ii) procedures for reporting leaks, spills, and other releases in accordance with Part III G; (2) Prevent the discharge of spilled and leaked fuels and chemicals from vehicle fueling and maintenance activities (e.g., providing secondary containment such as spill berms, decks, spill containment pallets, providing cover where appropriate, and having spill kits readily available); (3) Prevent the discharge of soaps, solvents, detergents, and wash water from construction materials, including the clean-up of stucco, paint, form release oils, and curing compounds (e.g., providing (i) cover (e.g., plastic sheeting or temporary roofs) to prevent contact with stormwater; (ii) collection and proper disposal in a manner to prevent contact with stormwater; and (iii) a similarly effective means designed to prevent discharge of these pollutants); (4) Minimize the discharge of pollutants from vehicle and equipment washing, wheel wash water, and other types of washing (e.g., locating activities away from surface waters and stormwater inlets or conveyance and directing wash waters to sediment basins or traps, using filtration devices such as filter bags or sand filters, or using similarly effective controls); (5) Direct concrete wash water into a leak-proof container or leak-proof settling basin. The container or basin shall be designed so that no overflows can occur due to inadequate sizing or precipitation. Hardened concrete wastes shall be removed and disposed of in a manner consistent with the handling of other construction wastes. Liquid concrete wastes shall be removed and disposed of in a manner consistent with the handling of other construction wash waters and shall not be discharged to surface waters; (6) Minimize the discharge of pollutants from storage, handling, and disposal of construction products, materials, and wastes including (i) building products such as asphalt sealants, copper flashing, roofing materials, adhesives, and concrete admixtures; (ii) pesticides, herbicides, insecticides, fertilizers, and landscape Page 10 of 26 materials; and (iii) construction and domestic wastes such as packaging materials, scrap construction materials, masonry products, timber, pipe and electrical cuttings, plastics, Styrofoam, concrete, and other trash or building materials; (7) Prevent the discharge of fuels, oils, and other petroleum products, hazardous or toxic wastes, waste concrete, and sanitary wastes; (8) Address any other discharge from the potential pollutant-generating activities not addressed above; (9) Minimize the exposure of waste materials to precipitation by closing or covering waste containers during precipitation events and at the end of the business day, or implementing other similarly effective practices. Minimization of exposure is not required in cases where the exposure to precipitation will not result in a discharge of pollutants; and f. Describe procedures for providing pollution prevention awareness of all applicable wastes, including any wash water, disposal practices, and applicable disposal locations of such wastes, to personnel in order to comply with the conditions of this general permit. The operator shall implement the procedures described in the SWPPP. 5. SWPPP requirements for discharges to nutrient and sediment impaired waters. For discharges to surface waters (i) identified as impaired in the 2016 § 305(b)/303(d) Water Quality Assessment Integrated Report or (ii) with an applicable TMDL wasteload allocation established and approved prior to the term of this general permit for sediment for a sediment- related parameter (i.e., total suspended solids or turbidity) or nutrients (i.e., nitrogen or phosphorus), the operator shall: a. Identify the impaired waters, approved TMDLs, and pollutants of concern in the SWPPP; and b. Provide clear direction in the SWPPP that: (1) Permanent or temporary soil stabilization shall be applied to denuded areas within seven days after final grade is reached on any portion of the site; (2) Nutrients shall be applied in accordance with manufacturer's recommendations or an approved nutrient management plan and shall not be applied during rainfall events; and (3) A modified inspection schedule shall be implemented in accordance with Part II G 2 a. 6. SWPPP requirements for discharges to polychlorinated biphenyl (PCB) impaired waters. For discharges from construction activities that include the demolition of any structure with at least 10,000 square feet of floor space built or renovated before January 1, 1980, to surface waters (i) identified as impaired in the 2016 § 305(b)/303(d) Water Quality Assessment Integrated Report or(ii)with an applicable TMDL wasteload allocation established and approved prior to the term of this general permit for PCB, the operator shall: - Page 11 of 26 a. Identify the impaired waters, approved TMDLs, and pollutant of concern in the SWPPP; b. Implement the approved erosion and sediment control plan in accordance with Part II B 2; c. Dispose of waste materials in compliance with applicable state, federal, and local requirements; and d. Implement a modified inspection schedule in accordance with Part II G 2 a. 7. SWPPP requirements for discharges to exceptional waters. For discharges to surface waters identified in 9VAC25-260-30 A 3 c as an exceptional water, the operator shall: a. Identify the exceptional,surface waters in the SWPPP; and b. Provide clear direction in the SWPPP that: (1) Permanent or temporary soil stabilization shall be applied to denuded areas within seven days after final grade is reached on any portion of the site; (2) Nutrients shall be applied in accordance with manufacturer's recommendations or an approved nutrient management plan and shall not be applied during rainfall events; and (3) A modified inspection schedule shall be implemented in accordance with Part II G 2 a. 8. Identification of qualified personnel. The name, phone number, and qualifications of the qualified personnel conducting inspections required by this general permit. 9. Delegation of authority. The individuals or positions with delegated authority, in accordance with Part III K, to sign inspection reports or modify the SWPPP. 10. SWPPP signature. The SWPPP shall be signed and dated in accordance with Part III K. C. SWPPP amendments, modification, and updates. 1. The operator shall amend the SWPPP whenever there is a change in the design, construction, operation, or maintenance that has a significant effect on the discharge of pollutants to surface waters and that has not been previously addressed in the SWPPP. 2. The SWPPP shall be amended if, during inspections or investigations by the operator's qualified personnel, or by local, state, or federal officials, it is determined that the existing control measures are ineffective in minimizing pollutants in discharges from the construction activity. Revisions to the SWPPP shall include additional or modified control measures designed and implemented to correct problems identified. If approval by the VESCP authority, VSMP authority, or department is necessary for the control measure, revisions to the SWPPP shall be completed no later than seven calendar days following approval. Implementation of these additional or modified control measures shall be accomplished as described in Part II H. Page 12 of 26 3. The SWPPP shall clearly identify the contractors that will implement and maintain each control measure identified in the SWPPP. The SWPPP shall be amended to identify any new contractor that will implement and maintain a control measure. 4. The operator shall update the SWPPP as soon as possible but no later than seven days following any modification to its implementation. All modifications or updates to the SWPPP shall be noted and shall include the following items: a. A record of dates when: (1) Major grading activities occur; (2) Construction activities temporarily or permanently cease on a portion of the site; and (3) Stabilization measures are initiated; b. Documentation of replaced or modified controls where periodic inspections or other information have indicated that the controls have been used inappropriately or incorrectly and were modified; c. Areas that have reached final stabilization and where no further SWPPP or inspection requirements apply; d. All properties that are no longer under the legal control of the operator and the dates on which the operator no longer had legal control over each property; e. The date of any prohibited discharges, the discharge volume released, and what actions were taken to minimize the impact of the release; f. Measures taken to prevent the reoccurrence of any prohibited discharge; and g. Measures taken to address any evidence identified as a result of an inspection required under Part II G. 5. Amendments, modifications, or updates to the SWPPP shall be signed in accordance with Part III K. D. Public notification. Upon commencement of land disturbance, the operator shall post conspicuously a copy of the notice of coverage letter near the main entrance of the construction activity. For linear projects, the operator shall post the notice of coverage letter at a publicly accessible location near an active part of the construction project (e.g., where a pipeline crosses a public road). The operator shall maintain the posted information until termination of general permit coverage as specified in Part I F. E. SWPPP availability. 1. Operators with day-to-day operational control over SWPPP implementation shall have a copy of the SWPPP available at a central location on-site for use by those identified as having responsibilities under the SWPPP whenever they are on the construction site. Page 13 of 26 2. The operator shall make the SWPPP and all amendments, modifications, and updates available upon request to the department, the VSMP authority, the EPA, the VESCP authority, local government officials, or the operator of a municipal separate storm sewer system receiving discharges from the construction activity. If an on-site location is unavailable to store the SWPPP when no personnel are present, notice of the SWPPP's location shall be posted near the main entrance of the construction site. 3. The operator shall make the SWPPP available for public review in an electronic format or in hard copy. Information for public access to the SWPPP shall be posted and maintained in accordance with Part II D. If not provided electronically, public access to the SWPPP may be arranged upon request at a time and at a publicly accessible location convenient to the operator or his designee but shall be no less than once per month and shall be during normal business hours. Information not required to be contained within the SWPPP by this general permit is not required to be released. F. SWPPP implementation. The operator shall implement the SWPPP and subsequent amendments, modifications, and updates from commencement of land disturbance until termination of general permit coverage as specified in Part I F. 1. All control measures shall be properly maintained in effective operating condition in accordance with good engineering practices and, where applicable, manufacturer specifications. If a site inspection required by Part II G identifies a control measure that is not operating effectively, corrective actions shall be completed as soon as practicable, but no later than seven days after discovery or a longer period as established by the VSMP authority, to maintain the continued effectiveness of the control measures. 2. If site inspections required by Part II G identify an existing control measure that needs to be modified or if an additional or alternative control measure is necessary for any reason, implementation shall be completed prior to the next anticipated measurable storm event. If implementation prior to the next anticipated measurable storm event is impracticable, then additional or alternative control measures shall be implemented as soon as practicable, but no later than seven days after discovery or a longer period as established by the VSMP authority. G. SWPPP Inspections. 1. Personnel responsible for on-site and off-site inspections. Inspections required by this general permit shall be conducted by the qualified personnel identified by the operator in the SWPPP. The operator is responsible for ensuring that the qualified personnel conduct the inspection. 2. Inspection schedule. a. For construction activities that discharge to a surface water identified in Part II B 5 and B 6 as impaired or having an approved TMDL or Part I B 7 as exceptional, the following inspection schedule requirements apply: (1) Inspections shall be conducted at a frequency of (i) at least once every four business days or(ii) at least once every five business days and no later than 24 hours following a measurable storm event. In the event that a measurable storm event occurs when Page 14 of 26 there are more than 24 hours between business days, the inspection shall be conducted on the next business day; and (2) Representative inspections as authorized in Part II G 2 d shall not be allowed. b. Except as specified in Part II G 2 a, inspections shall be conducted at a frequency of: (1) At least once every five business days; or (2) At least once every 10 business days and no later than 24 hours following a measurable storm event. In the event that a measurable storm event occurs when there are more than 24 hours between business days, the inspection shall be conducted on the next business day. c. Where areas have been temporarily stabilized or land-disturbing activities will be suspended due to continuous frozen ground conditions and stormwater discharges are unlikely, the inspection frequency described in Part II G 2 a and 2 b may be reduced to once per month. If weather conditions (such as above freezing temperatures or rain or snow events) make discharges likely, the operator shall immediately resume the regular inspection frequency. d. Except as prohibited in Part II G 2 a (2), representative inspections may be utilized for utility line installation, pipeline construction, or other similar linear construction activities provided that: (1) Temporary or permanent soil stabilization has been installed and vehicle access may compromise the temporary or permanent soil stabilization and potentially cause additional land disturbance increasing the potential for erosion; (2) Inspections occur on the same frequency as other construction activities; (3) Control measures are inspected along the construction site 0.25 miles above and below each access point (i.e., where a roadway, undisturbed right-of-way, or other similar feature intersects the construction activity and access does not compromise temporary or permanent soil stabilization); and (4) Inspection locations are provided in the inspection report required by Part II G. e. If adverse weather causes the safety of the inspection personnel to be in jeopardy, the inspection may be delayed until the next business day on which it is safe to perform the inspection.Any time inspections are delayed due to adverse weather conditions, evidence of the adverse weather conditions shall be included in the SWPPP with the dates of occurrence. 3. Inspection requirements. a. As part of the inspection, the qualified personnel shall: (1) Record the date and time of the inspection and, when applicable, the date and rainfall amount of the last measurable storm event; Page 15 of 26 (2) Record the information and a description of any discharges occurring at the time of the inspection or evidence of discharges occurring prior to the inspection; (3) Record any land-disturbing activities that have occurred outside of the approved erosion and sediment control plan; (4) Inspect the following for installation in accordance with the approved erosion and sediment control plan, identification of any maintenance needs, and evaluation of effectiveness in minimizing sediment discharge, including whether the control has been inappropriately or incorrectly used: (a) All perimeter erosion and sediment controls, such as silt fence; (b) Soil stockpiles, when applicable, and borrow areas for stabilization or sediment trapping measures; (c) Completed earthen structures, such as dams, dikes, ditches, and diversions for stabilization and effective impoundment or flow control; (d) Cut and fill slopes; (e) Sediment basins and traps, sediment barriers, and other measures installed to control sediment discharge from stormwater; (f) Temporary or permanent channels, flumes, or other slope drain structures installed to convey concentrated runoff down cut and fill slopes; (g) Storm inlets that have been made operational to ensure that sediment laden stormwater does not enter without first being filtered or similarly treated; and (h) Construction vehicle access routes that intersect or access paved or public roads for minimizing sediment tracking; (5) Inspect areas that have reached final grade or that will remain dormant for more than 14 days to ensure: (a) Initiation of stabilization activities have occurred immediately, as defined in 9VAC25-880-1; and (b) Stabilization activities have been completed within seven days of reaching grade or stopping work; (6) Inspect for evidence that the approved erosion and sediment control plan, "agreement in lieu of a plan," or erosion and sediment control plan prepared in accordance with department-approved annual standards and specifications has not been properly implemented. This includes: Page 16 of 26 (a) Concentrated flows of stormwater in conveyances such as rills, rivulets, or channels that have not been filtered, settled, or similarly treated prior to discharge, or evidence thereof; (b) Sediment laden or turbid flows of stormwater that have not been filtered or settled to remove sediments prior to discharge; (c) Sediment deposition in areas that drain to unprotected stormwater inlets or catch basins that discharge to surface waters. Inlets and catch basins with failing sediment controls due to improper installation, lack of maintenance, or inadequate design are considered unprotected; (d) Sediment deposition on any property (including public and private streets) outside of the construction activity covered by this general permit; (e) Required stabilization has not been initiated or completed or is not effective on portions of the site; (f) Sediment basins without adequate wet or dry storage volume or sediment basins that allow the discharge of stormwater from below the surface of the wet storage portion of the basin; (g) Sediment traps without adequate wet or dry storage or sediment traps that allow the discharge of stormwater from below the surface of the wet storage portion of the trap; and (h) Land disturbance or sediment deposition outside of the approved area to be _ disturbed; (7) Inspect pollutant generating activities identified in the pollution prevention plan for the proper implementation, maintenance, and effectiveness of the procedures and practices; (8) Identify any pollutant generating activities not identified in the pollution prevention plan; and (9) Identify and document the presence of any evidence of the discharge of pollutants prohibited by this general permit. 4. Inspection report. Each inspection report shall include the following items: a. The date and time of the inspection and, when applicable, the date and rainfall amount of the last measurable storm event; b. Summarized findings of the inspection; c. The locations of prohibited discharges; d. The locations of control measures that require maintenance; Page 17 of 26 e. The locations of control measures that failed to operate as designed or proved inadequate or inappropriate for a particular location; f. The locations where any evidence identified under Part II G 3 a (6) exists; g. The locations where any additional control measure is needed; h. A list of corrective actions required (including any changes to the SWPPP that are necessary) as a result of the inspection or to maintain permit compliance; i. Documentation of any corrective actions required from a previous inspection that have not been implemented; and j. The date and signature of the qualified personnel and the operator or its duly authorized representative. 5. The inspection report shall be included into the SWPPP no later than four business days after the inspection is complete. 6. The inspection report and any actions taken in accordance with Part II shall be retained by the operator as part of the SWPPP for at least three years from the date that general permit coverage expires or is terminated. The inspection report shall identify any incidents of noncompliance.Where an inspection report does not identify any incidents of noncompliance, the report shall contain a certification that the construction activity is in compliance with the SWPPP and this general permit. The report shall be signed in accordance with Part III K of this general permit. H. Corrective actions. 1. The operator shall implement the corrective actions identified as a result of an inspection as soon as practicable but no later than seven days after discovery or a longer period as approved by the VSMP authority. If approval of a corrective action by a regulatory authority (e.g., VSMP authority, VESCP authority, or the department) is necessary, additional control measures shall be implemented to minimize pollutants in stormwater discharges until such approvals can be obtained. 2. The operator may be required to remove accumulated sediment deposits located outside of the construction activity covered by this general permit as soon as practicable in order to minimize environmental impacts. The operator shall notify the VSMP authority and the department as well as obtain all applicable federal, state, and local authorizations, approvals, and permits prior to the removal of sediments accumulated in surface waters including wetlands. Page 18 of 26 PART III CONDITIONS APPLICABLE TO ALL VPDES PERMITS • - NOTE: Discharge monitoring is not required for this general permit. If the operator chooses to monitor stormwater discharges or control measures, the operator shall comply with the requirements of subsections A, B, and C, as appropriate. A. Monitoring. 1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitoring activity. 2. Monitoring shall be conducted according to procedures approved under 40 CFR Part 136 or alternative methods approved by the U.S. Environmental Protection Agency, unless other procedures have been specified in this general permit. Analyses performed according to test procedures approved under 40 CFR Part 136 shall be performed by an environmental laboratory certified under regulations adopted by the Department of General Services (1 VAC30-45 or 1 VAC30-46). 3. The operator shall periodically calibrate and perform maintenance procedures on all monitoring and analytical instrumentation at intervals that will ensure accuracy of measurements. B. Records. 1. Monitoring records and reports shall include: a. The date, exact place, and time of sampling or measurements; b. The individuals who performed the sampling or measurements; c. The dates and times analyses were performed; d. The individuals who performed the analyses; e. The analytical techniques or methods used; and f. The results of such analyses. 2. The operator shall retain records of all monitoring information, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this general permit, and records of all data used to complete the registration statement for this general permit, for a period of at least three years from the date of the sample, measurement, report or request for coverage. This period of retention shall be extended automatically during the course of any unresolved litigation regarding the regulated activity or regarding control standards applicable to the operator, or as requested by the board. C. Reporting monitoring results. Page 19 of 26 1. The operator shall update the SWPPP to include the results of the monitoring as may be performed in accordance with this general permit, unless another reporting schedule is specified elsewhere in this general permit. 2. Monitoring results shall be reported on a discharge monitoring report (DMR); on forms provided, approved or specified by the department; or in any format provided that the date, location, parameter, method, and result of the monitoring activity are included. 3. If the operator monitors any pollutant specifically addressed by this general permit more frequently than required by this general permit using test procedures approved under 40 CFR Part 136 or using other test procedures approved by the U.S. Environmental Protection Agency or using procedures specified in this general permit,the results of this monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the department. 4. Calculations for all limitations which require averaging of measurements shall utilize an arithmetic mean unless otherwise specified in this general permit. D. Duty to provide information. The operator shall furnish, within a reasonable time, any information which the board may request to determine whether cause exists for terminating this general permit coverage or to determine compliance with this general permit. The board, department, EPA, or VSMP authority may require the operator to furnish, upon request, such plans, specifications, and other pertinent information as may be necessary to determine the effect of the wastes from his discharge on the quality of surface waters, or such other information as may be necessary to accomplish the purposes of the CWA and the Virginia Stormwater Management Act. The operator shall also furnish to the board, department, EPA, or VSMP authority, upon request, copies of records required to be kept by this general permit. E. Compliance schedule reports. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this general permit shall be submitted no later than 14 days following each schedule date. F. Unauthorized stormwater discharges. Pursuant to § 62.1-44.5 of the Code of Virginia, except in compliance with a state permit issued by the department, it shall be unlawful to cause a stormwater discharge from a construction activity. G. Reports of unauthorized discharges. Any operator who discharges or causes or allows a discharge of sewage, industrial waste, other wastes or any noxious or deleterious substance or a hazardous substance or oil in an amount equal to or in excess of a reportable quantity established under either 40 CFR Part 110, 40 CFR Part 117,40 CFR Part 302, or§62.1-44.34:19 of the Code of Virginia that occurs during a 24-hour period into or upon surface waters or who discharges or causes or allows a discharge that may reasonably be expected to enter surface waters, shall notify the Department of Environmental Quality of the discharge immediately upon discovery of the discharge, but in no case later than within 24 hours after said discovery. A written report of the unauthorized discharge shall be submitted to the department and the VSMP authority within five days of discovery of the discharge. The written report shall contain: 1. A description of the nature and location of the discharge; 2. The cause of the discharge; Page 20 of 26 3. The date on which the discharge occurred; 4. The length of time that the discharge continued; 5. The volume of the discharge; 6. If the discharge is continuing, how long it is expected to continue; 7. If the discharge is continuing, what the expected total volume of the discharge will be; and 8. Any steps planned or taken to reduce, eliminate and prevent a recurrence of the present discharge or any future discharges not authorized by this general permit. Discharges reportable to the department and the VSMP authority under the immediate reporting requirements of other regulations are exempted from this requirement. H. Reports of unusual or extraordinary discharges. If any unusual or extraordinary discharge including a "bypass" or"upset," as defined in this general permit, should occur from a facility and the discharge enters or could be expected to enter surface waters, the operator shall promptly notify, in no case later than within 24 hours, the department and the VSMP authority by telephone after the discovery of the discharge. This notification shall provide all available details of the incident, including any adverse effects on aquatic life and the known number of fish killed. The operator shall reduce the report to writing and shall submit it to the department and the VSMP authority within five days of discovery of the discharge in accordance with Part III 12. Unusual and extraordinary discharges include any discharge resulting from: 1. Unusual spillage of materials resulting directly or indirectly from processing operations; 2. Breakdown of processing or accessory equipment; 3. Failure or taking out of service of some or all of the facilities; and 4. Flooding or other acts of nature. I. Reports of noncompliance. The operator shall report any noncompliance which may adversely affect surface waters or may endanger public health. 1. An oral report to the department and the VSMP authority shall be provided within 24 hours from the time the operator becomes aware of the circumstances. The following shall be included as information that shall be reported within 24 hours under this subdivision: a. Any unanticipated bypass; and b. Any upset that causes a discharge to surface waters. 2. A written report shall be submitted within five days and shall contain: a. A description of the noncompliance and its cause; Page 21 of 26 b. The period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and c. Steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. The department may waive the written report on a case-by-case basis for reports of noncompliance under Part Ill I if the oral report has been received within 24 hours and no adverse impact on surface waters has been reported. 3. The operator shall report all instances of noncompliance not reported under Part III 11 or 2 in writing as part of the SWPPP. The reports shall contain the information listed in Part Ill 12. NOTE: The reports required in Part III G, H and I shall be made to the department and the VSMP authority. Reports may be made by telephone, email, or by fax. For reports outside normal working hours, leaving a recorded message shall fulfill the immediate reporting requirement. For emergencies, the Virginia Department of Emergency Management maintains a 24-hour telephone service at 1-800-468-8892. 4. Where the operator becomes aware of a failure to submit any relevant facts, or submittal of incorrect information in any report, including a registration statement, to the department or the VSMP authority, the operator shall promptly submit such facts or correct information. J. Notice of planned changes. 1. The operator shall give notice to the department and the VSMP authority as soon as possible of any planned physical alterations or additions to the permitted facility or activity. Notice is required only when: a. The operator plans an alteration or addition to any building, structure,facility, or installation that may meet one of the criteria for determining whether a facility is a new source in 9VAC25-870-420; b. The operator plans an alteration or addition that would significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this general permit; or 2. The operator shall give advance notice to the department and VSMP authority of any planned changes in the permitted facility or activity, which may result in noncompliance with state permit requirements. K. Signatory requirements. 1. Registration statement. All registration statements shall be signed as follows: a. For a corporation: by a responsible corporate officer. For the purpose of this chapter, a responsible corporate officer means: (i)a president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy-making or decision-making functions for the corporation; or(ii) the manager of one or more manufacturing, production, or operating facilities, provided the Page 22 of 26 manager is authorized to make management decisions that govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long-term compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for state permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures; b. For a partnership or sole proprietorship: by a general partner or the proprietor, respectively; or c. For a municipality, state, federal, or other public agency: by either a principal executive officer or ranking elected official. For purposes of this chapter, a principal executive officer of a public agency includes (i) the chief executive officer of the agency or (ii) a senior executive officer having responsibility for the overall operations of a principal geographic unit of the agency. 2. Reports and other information. All reports required by this general permit, including SWPPPs, and other information requested by the board or the department shall be signed by a person described in Part Ill K 1 or by a duly authorized representative of that person. A person is a duly authorized representative only if: a. The authorization is made in writing by a person described in Part Ill K 1; b. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the operator. (A duly authorized representative may thus be either a named individual or any individual occupying a named position); and c. The signed and dated written authorization is included in the SWPPP. A copy shall be provided to the department and VSMP authority, if requested. 3. Changes to authorization. If an authorization under Part III K 2 is no longer accurate because a different individual or position has responsibility for the overall operation of the construction activity, a new authorization satisfying the requirements of Part III K 2 shall be submitted to the VSMP authority as the administering entity for the board prior to or together with any reports or information to be signed by an authorized representative. 4. Certification. Any person signing a document under Part III K 1 or 2 shall make the following certification: 5. "I certify under penalty of law that I have read and understand this document and that this document and all attachments were prepared in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant Page 23 of 26 penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." L. Duty to comply. The operator shall comply with all conditions of this general permit. Any state permit noncompliance constitutes a violation of the Virginia Stormwater Management Act and the Clean Water Act, except that noncompliance with certain provisions of this general permit may constitute a violation of the Virginia Stormwater Management Act but not the Clean Water Act. Permit noncompliance is grounds for enforcement action; for state permit coverage, termination, revocation and reissuance, or modification; or denial of a state permit renewal application. The operator shall comply with effluent standards or prohibitions established under § 307(a) of the Clean Water Act for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions or standards for sewage sludge use or disposal, even if this general permit has not yet been modified to incorporate the requirement. M. Duty to reapply. If the operator wishes to continue an activity regulated by this general permit after the expiration date of this general permit, the operator shall submit a new registration statement at least 60 days before the expiration date of the existing general permit, unless permission for a later date has been granted by the board. The board shall not grant permission for registration statements to be submitted later than the expiration date of the existing general permit. N. Effect of a state permit. This general permit does not convey any property rights in either real or personal property or any exclusive privileges, nor does it authorize any injury to private property or invasion of personal rights, or any infringement of federal, state or local law or regulations. O. State law. Nothing in this general permit shall be construed to preclude the institution of any legal action under, or relieve the operator from any responsibilities, liabilities, or penalties established pursuant to any other state law or regulation or under authority preserved by§ 510 of the Clean Water Act. Except as provided in general permit conditions on "bypassing" (Part III U) and "upset" (Part III V), nothing in this general permit shall be construed to relieve the operator from civil and criminal penalties for noncompliance. P. Oil and hazardous substance liability. Nothing in this general permit shall be construed to preclude the institution of any legal action or relieve the operator from any responsibilities, liabilities, or penalties to which the operator is or may be subject under§§ 62.1-44.34:14 through 62.1-44.34:23 of the State Water Control Law or§ 311 of the Clean Water Act. Q. Proper operation and maintenance. The operator shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances), which are installed or used by the operator to achieve compliance with the conditions of this general permit. Proper operation and maintenance also includes effective plant performance, adequate funding, adequate staffing, and adequate laboratory and process controls, including appropriate quality assurance procedures. This provision requires the operation of back-up or auxiliary facilities or similar systems, which are installed by the operator only when the operation is necessary to achieve compliance with the conditions of this general permit. R. Disposal of solids or sludges. Solids, sludges or other pollutants removed in the course of treatment or management of pollutants shall be disposed of in a manner so as to prevent any pollutant from such materials from entering surface waters and in compliance with all applicable state and federal laws and regulations. Page 24 of 26 S. Duty to mitigate. The operator shall take all steps to minimize or prevent any discharge in violation of this general permit that has a reasonable likelihood of adversely affecting human health or the environment. T. Need to halt or reduce activity not a defense. It shall not be a defense for an operator in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this general permit. U. Bypass. 1. "Bypass," as defined in 9VAC25-870-10, means the intentional diversion of waste streams from any portion of a treatment facility. The operator may allow any bypass to occur that does not cause effluent limitations to be exceeded, but only if it also is for essential maintenance to ensure efficient operation. These bypasses are not subject to the provisions of Part Ill U 2 and 3. 2. Notice. a. Anticipated bypass. If the operator knows in advance of the need for a bypass, the operator shall submit prior notice to the department, if possible at least 10 days before the date of the bypass. b. Unanticipated bypass. The operator shall submit notice of an unanticipated bypass as required in Part III I. 3. Prohibition of bypass. a. Except as provided in Part III U 1, bypass is prohibited, and the board or department may take enforcement action against an operator for bypass unless: (1) Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage. Severe property damage means substantial physical damage to property, damage to the treatment facilities that causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production; (2) There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back-up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance; and (3) The operator submitted notices as required under Part III U 2. b. The department may approve an anticipated bypass, after considering its adverse effects, if the department determines that it will meet the three conditions listed in Part III U 3 a. Page 25 of 26 V. Upset. 1. An "upset," as defined in 9VAC25-870-10, means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based state permit effluent limitations because of factors beyond the reasonable control of the operator. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. 2. An upset constitutes an affirmative defense to an action brought for noncompliance with technology-based state permit effluent limitations if the requirements of Part III V 4 are met. A determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is not a final administrative action subject to judicial review. 3. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventative maintenance, or careless or improper operation. 4. An operator who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that: a. An upset occurred and that the operator can identify the cause of the upset; b. The permitted facility was at the time being properly operated; c. The operator submitted notice of the upset as required in Part III I; and d. The operator complied with any remedial measures required under Part III S. 5. In any enforcement proceeding, the operator seeking to establish the occurrence of an upset has the burden of proof. W. Inspection and entry. The operator shall allow the department as the board's designee, the VSMP authority, EPA, or an authorized representative of either entity (including an authorized contractor), upon presentation of credentials and other documents as may be required by law to: 1. Enter upon the operator's premises where a regulated facility or activity is located or conducted, or where records shall be kept under the conditions of this general permit; 2. Have access to and copy, at reasonable times, any records that shall be kept under the conditions of this general permit; 3. Inspect and photograph at reasonable times any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this general permit; and 4. Sample or monitor at reasonable times, for the purposes of ensuring state permit compliance or as otherwise authorized by the Clean Water Act or the Virginia Stormwater Management Act, any substances or parameters at any location. Page 26 of 26 For purposes of this section, the time for inspection shall be deemed reasonable during regular business hours, and whenever the facility is discharging. Nothing contained herein shall make an inspection unreasonable during an emergency. X. State permit actions. State permit coverage may be modified, revoked and reissued, or terminated for cause. The filing of a request by the operator for a state permit modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any state permit condition. Y. Transfer of state permit coverage. 1. State permits are not transferable to any person except after notice to the department. Except as provided in Part III Y 2, a state permit may be transferred by the operator to a new operator only if the state permit has been modified or revoked and reissued, or a minor modification made, to identify the new operator and incorporate such other requirements as may be necessary under the Virginia Stormwater Management Act and the Clean Water Act. 2. As an alternative to transfers under Part III Y 1, this state permit may be automatically transferred to a new operator if: a. The current operator notifies the department at least 30 days in advance of the proposed transfer of the title to the facility or property; b. The notice includes a written agreement between the existing and new operators containing a specific date for transfer of state permit responsibility, coverage, and liability between them; and c. The department does not notify the existing operator and the proposed new operator of its intent to modify or revoke and reissue the state permit. If this notice is not received, the transfer is effective on the date specified in the agreement mentioned in Part III Y 2 b. 3. For ongoing construction activity involving a change of operator,the new operator shall accept and maintain the existing SWPPP, or prepare and implement a new SWPPP prior to taking over operations at the site. Z. Severability. The provisions of this general permit are severable, and if any provision of this general permit or the application of any provision of this state permit to any circumstance, is held invalid, the application of such provision to other circumstances and the remainder of this general permit shall not be affected thereby. APPX C- VSMP Registration Statement, Notice of Coverage Letter, and Notice of Termination (if applicable) 281 — VIRGINIA DEPARTMENT OF ENVIRONMENTAL QUALITY FOR OFFICE USE ONLY GENERAL VPDES PERMIT FOR DISCHARGES OF STORMWATER FROM ID Number: CONSTRUCTION ACTIVITIES (VAR10) Technical Criteria: IIB ❑ IIC ❑ REGISTRATION STATEMENT 2019 NEW ISSUANCE 0 RE-ISSUANCE ❑ MODIFICATION WITH ACREAGE INCREASE ❑ MODIFICATION WITHOUT ACREAGE INCREASE ❑ Existing Permit Coverage Number(if applicable,VAR10####): Section I. Operator/Permittee Information. A. Construction Activity Operator(Permittee). The person or entity that is applying for permit coverage and will have operational control over construction activities to ensure compliance with the general permit. A person with signatory authority for this operator must sign the certification in Section VI. (per Part III. K. of the VAR10 Permit). Construction Activity Operator Name: BMC Holdings Group, LLC Contact person: Reid Murphy Address: 400 Locust Ave.Suite 3 City,State,Zip Code: Charlottesville,VA 22902 Phone Number: (434) 977-6406 - Primary Email: reid@bmcholdingsgroup.com CC Email: riki@roudabush.com B. Billing Information (leave blank if same as the Operator identified in Section I.A.above). This entity will receive Annual Permit Maintenance and Permit Modification Fee invoices (if applicable). Name: Contact Person: Address: City,State Zip Code: Phone Number: Primary Email: CC Email: C. May we transmit correspondence electronically? You must choose YES and include a valid email in order to pay by credit card and to receive your permit coverage approval letter via email: YES ❑x NO ❑ Rev 04/2019 PAGE 1 17 CONSTRUCTION GENERAL PERMIT(VAR10) REGISTRATION STATEMENT 2019 Section II. Construction Activity Location Information. Project site information. -- `I A. Include a site map showing the location of the existing or proposed land-disturbing activities,the limits of land disturbance, construction entrances and all water bodies receiving stormwater discharges from the site. B. Construction Activity Name: Georgetown Hydraulic Address: Intersection of Georgetown Rd. and Hydraulic Rd. City and/or County and Zip Code: Charlottesville,VA Latitude and Longitude (6-digit,decimal degrees format): 38.071356,-78.499325 C. Construction Activity Entrance Location (description,street address and/or latitude/longitude in decimal degrees): 38.071356,-78.499325 Section III. Offsite Support Activity Location Information. List all offsite support activities to be included under this permit registration. Enter additional areas on a separate page. Offsite areas not included on this registration may need to obtain coverage under a separate VPDES permit. A. Offsite Activity Name: Address: City and/or County and Zip Code: Latitude and Longitude (6-digit, decimal degrees format): B. Offsite Activity Entrance Location (description,street address and/or latitude/longitude in decimal degrees): Section IV. Site Information. A. Acreage totals for all land-disturbing activities to be included under this B. Estimated Project Dates permit coverage. Report to the nearest one-hundredth of an acre. (MM/DD/YYYY) Total land area of development(including the entire area to be disturbed as approved in the Stormwater 1.05 acres Start date: 12/1/2019 Management Plan): Primary estimated area to be disturbed (portions with Erosion and Sediment Control Plan approval only): 0.88 acres Completion date: Offsite estimated area to be disturbed (if applicable): 05/31/2024 C. Property Owner Status: FEDERAL ❑ STATE ❑ PUBLIC ❑ PRIVATE ❑x D. Nature of the Construction Activity Description(i.e. commercial, industrial, residential, agricultural, environmental): Commercial E. Municipal Separate Storm Sewer System (MS4) name (if discharging to a MS4): - Rev 04/2019 PAGE 2 17 CONSTRUCTION GENERAL PERMIT(VAR10) REGISTRATION STATEMENT 2019 F. Is this construction activity part of a common plan of development or sale? YES ❑ NO 111 G. 6th Order Hydrologic Unit Code(HUC) and Receiving Water Name(s). Attach a separate list if needed. HUC RECEIVING WATERBODY(S) JR07 (HUCO20802040202 Ivy Creek-Little Ivy Creek Section V. Other Information. A. A stormwater pollution prevention plan (SWPPP) must be prepared in accordance with the requirements of the General VPDES Permit for Discharges of Stormwater from Construction Activities prior to submitting the Registration Statement. By signing the Registration Statement,the operator is certifying that the SWPPP has been prepared. B. Has an Erosion and Sediment Control Plan been submitted to the VESCP Authority for review? YES ® NO ❑ Erosion and Sediment Control Plan Approval Date (for estimated area to be disturbed).: C. Has land disturbance has commenced? YES ❑ NO ❑x D. If this project is using approved Annual Standards and Specifications(AS&S), attach the completed AS&S Entity Form. AS&S Entity Name (if different from the Operator identified in Section II.A.): SEE THE FOLLOWING PAGE FOR SIGNATURE AND CERTIFICATION REQUIREMENTS AND INFORMATION Rev 04/2019 PAGE 3 17 CONSTRUCTION GENERAL PERMIT(VAR10)REGISTRATION STATEMENT 2019 Section VI. Certification. A person representing the operator as identified in Section I.A.and meeting the requirements of 9VAC25-880-70.Part III.K must physically sign this certification. A typed signature is not acceptable. Please note that operator is defined in 9VAC25-870-10 as follows: "Operator"means the owner or operator of any facility or activity subject to the Act and this chapter.In the context of stormwater associated with a large or small construction activity,operator means any person associated with a construction project that meets either of the following two criteria:(i)the person has direct operational control over construction plans and specifications,including the ability to make modifications to those plans and specifications or(ii)the person has day-to-day operational control of those activities at a project that are necessary to ensure compliance with a stormwater pollution prevention plan for the site or other state permit or VSMP authority permit conditions(i.e.,they are authorized to direct workers at a site to carry out activities required by the stormwater pollution prevention plan or comply with other permit conditions).In the context of stormwater discharges from Municipal Separate Storm Sewer Systems(MS4s),operator means the operator of the regulated MS4 system. 9VAC25-880-70.Part III.K.Signatory Requirements.Registration Statement.All Registration Statements shall be signed as follows: a.For a corporation:by a responsible corporate officer.For the purpose of this chapter,a responsible corporate officer means:(I)a president,secretary,treasurer,or vice-president of the corporation in charge of a principal business function,or any other person who performs similar policy-making or decision-making functions for the corporation;or(ii)the manager of one or more manufacturing,production,or operating facilities,provided the manager is authorized to make management decisions that govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations,and initiating and directing other comprehensive measures to assure long-term. compliance with envi►onmental laws and regulations;the manager can ensure that the necessary systems ore established or actions taken to gather complete and accurate information for state permit application requirements;and where authority to sign documents has been assigned or delegated to the manager In accordance with corporate procedures; b.For a partnership or sole proprietorship:by a general partner or the proprietor,respectively;or c.For a municipality,state,federal,or other public agency:by either a principal executive officer or ranking elected official. For purposes of this chapter,a principal executive officer of a public agency includes:(I)the chief executive officer of the agency or(ii)a senior executive officer having responsibility for the overall operations of a principal geographic unit of the agency. Certification: "I certify under penalty of law that I have read and understand this Registration Statement and that this document and all attachments were prepared in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information,the information submitted is to the best- of my knowledge and belief true,accurate,and complete.. I am aware that there are significant penalties for submitting false information including the possibility of fine and imprisonment for knowing violations." Printed Name: '' )\. u (.1./ Signature(signed in ink): .. Date: 7/io/1'z Section VIi.Submittal Instructions. Submit this form to the Virginia Stormwater Management Program(VSMP) Authority. If the locality is the VSMP Authority, please send your Registration Statement submittal directly to the locality;do NOT send this form to DEQ. A list of local VSMP Authorities is available here: VSMP Authorities. If DEQ is the VSMP Authority,please send to: If the locality is the VSMP Authority,please send to: Department of Environmental Quality The Local VSMP Authority(insert address below) Office of Stormwater Management Suite 1400 PO Box 1105 Albemarle County Department of Community Development Richmond VA 23218 401 McIntire Rd. constructiongp@deq.virginia.gov Charlottesville,VA 22902 (434)296-5832 Rev 04/2019 PAGE 4 17 CONSTRUCTION GENERAL PERMIT(VAR10) REGISTRATION STATEMENT 2019 INSTRUCTIONS PLEASE DO NOT PRINT OR SUBMIT This Registration Statement is for coverage under the General VPDES Permit for Discharges of Stormwater from Construction Activities. The following permit actions are covered by this form: new issuance,re-issuance,modification with an increase in acreage and plan modifications that do not result in an increase in acreage. Choose NEW ISSUANCE if this Registration Statement submittal is to obtain a new permit coverage,RE-ISSUANCE to renew an active,expiring permit coverage or MODIFICATION to modify an active permit coverage When modifying permit coverage,indicate if the modification is increasing the amount of acreage previous covered(MODIFICATION WITH ACREAGE INCREASE)or changing the site design with no increase in acreage (MODIFICATION WITHOUT ACREAGE INCREASE). Existing Permit Coverage Number. Provide the permit number for a modification or reissuance(i.e.VAR10####). Section I. Operator/Permittee Information. A.Construction Activity Operator(Permittee). The person or entity that is applying for permit coverage and will have operational control over construction activities to ensure compliance with the general permit.For companies,use the complete,active,legal entity name as registered with a state corporation commission. Entities that are considered operators commonly consist of the property owner,developer of a project(the party with control of project plans and specifications),or general contractor(the party with day-to-day operational control of the activities at the project site that are necessary to ensure compliance with the general permit). If an individual person is named as the operator,that person(or a representative of)must sign the certification in Section VI. An operator can be one of the following: 9VAC25-870-10.Definitions. "Operator"means the owner or operator of any facility or activity subject to the Act and this chapter.In the context of storm water associated with a large or small construction activity,operator means any person associated with a construction project that meets either of the following two criteria:(i)the person has direct operational control over construction plans and specifications,including the ability to make modifications to those plans and specifications or(ii)the person has day-to-day operational control of those activities at a project that are necessary to ensure compliance with a stormwater pollution prevention plan for the site or other state permit or VSMP authority permit conditions(i.e.,they are authorized to direct workers at a site to carry out activities required by the stormwater pollution prevention plan or comply with other permit conditions).In the context of storm water discharges from Municipal Separate Storm Sewer Systems(MS4s),operator means the operator of the regulated MS4 system. "Owner"means the Commonwealth or any of its political subdivisions including,but not limited to,sanitation district commissions and authorities, and any public or private institution,corporation,association,firm or company organized or existing under the laws of this or any other state or country,or any officer or agency of the United States,or any person or group of persons acting individually or as a group that owns,operates, charters,rents,or otherwise exercises control over or is responsible for any actual or potential discharge of sewage,industrial wastes,or other wastes or pollutants to state waters,or any facility or operation that has the capability to alter the physical,chemical,or biological properties of state waters in contravention of§62.1-44.5 of the Code of Virginia,the Act and this chapter. "Person"means any individual,corporation,partnership,association,state,municipality,commission,or political subdivision of a state, governmental body,including a federal,state,or local entity as applicable,any interstate body or any other legal entity. B.Billing information. If the person or entity responsible for billing/invoicing is different from the operator,please complete this section. If they are the same,leave this section blank. C. May we transmit correspondence electronically? If you choose YES to this question and provide an email address in Section I.A.,all correspondence,forms,invoices and notifications will be transmitted by email to the operator. This will also allow the operator to pay by credit card and receive permit coverage approval letters immediately upon approval. Section II.Construction Activity Location Information. Location information related to the project site. A.A site map indicating the location of the existing or proposed land-disturbing activities,the limits of land disturbance,construction entrances and all water bodies receiving stormwater discharges from the site must be included with the submittal of this form.Aerial imagery maps or topographic maps showing the required items are acceptable. Plan sheet sized site maps are not required. Please consult your Virginia Stormwater Management Program(VSMP)authority if you have additional questions regarding site map requirements. B.Provide a descriptive project name(it is helpful to use the same naming convention as listed on the Stormwater plans),911 street address(if available),city/county of the construction activity,6-digit latitude and longitude in decimal degrees format for the centroid,main construction entrance or start and end points for linear projects(i.e.37.1234N/-77.1234W). C.Construction Activity Entrance Location. Provide an address or decimal degrees coordinates and a description of the main construction entrance where the permit coverage letter will be posted. Rev 04/2019 PAGE 5 17 CONSTRUCTION GENERAL PERMIT(VAR10) REGISTRATION STATEMENT 2019 INSTRUCTIONS PLEASE DO NOT PRINT OR SUBMIT Section III. Offsite Support Activity Location Information. This general permit also authorizes stormwater discharges from support activities(e.g.,concrete or asphalt batch plants,equipment staging yards, material storage areas,excavated material disposal areas,borrow areas)located on-site or off-site provided that(I)the support activity is directly related to a construction activity that is required to have general permit coverage;(ii)the support activity is not a commercial operation,nor does it serve multiple unrelated construction activities by different operators;(iii)the support activity does not operate beyond the completion of the construction activity it supports;(iv)the support activity is identified in the Registration Statement at the time of general permit coverage;(v) appropriate control measures are identified in a SWPPP and implemented to address the discharges from the support activity areas;and (vi)all applicable state,federal,and local approvals are obtained for the support activity. If requesting permit coverage for offsite activities,please complete this section. List additional offsite areas to be included under this permit coverage on a separate page. Offsite areas not included on this registration will need to obtain coverage under a separate VPDES permit. A. Offsite activity location information. Provide a descriptive offsite project name,911 street address(if available)and city/county of all off-site support activities.Provide the 6-digit latitude and longitude in decimal degrees(i.e.37.1234N,-77.1234W).Please note that off-site activities not covered under this permit may require separate permit coverage. B. Offsite activity entrance location. Provide an address or decimal degrees coordinates and a description of the main construction entrance. Section IV. Site Information. A.Acreage totals for all land-disturbing activities,on-and off-site,to be included under this permit. Acreages are to be reported to the nearest one-hundredth acre(two decimal places;i.e.1.15 acres). Provide the total acreage of the primary development site as approved on the Stormwater Management Plans and the primary on-site estimated acreage to be disturbed by the construction activity as approved under the Erosion and Sediment Control Plans.The off-site estimated area to be disturbed is the sum of the disturbed acreages for all off-site support activities to be covered under this general permit. Do not include the off-site acreage totals in the primary,on-site total and estimated disturbed acreage totals. Permit fees are calculated based on your disturbed acreage total for all on-and off-site areas being disturbed under this permit coverage(the sum of all on-site and off-site disturbed acreages). B.Estimated Project Dates. Provide the estimated project start date and completion date in Month/Day/Year or MM/DD/YYYY format(i.e. 07/30/2019). C.Property owner status. The status of the construction activity property owner. Any property not owned by a government entity or agency(i.e. federal,state or local governments)is PRIVATE. D.Nature of the construction activity description. Choose the designation that best describes the post-construction use of this project(you may choose more than one). (i.e.Residential,Commercial,Industrial,Agricultural,Environmental,Educational,Oil and Gas,Utility,Transportation, Institutional,etc.). Describe the project(i.e. Commercial—one new office building and associated parking and utilities;Transportation—Roads, sidewalks and utilities;Agricultural—3 Poultry Houses,etc.). E.Municipal Separate Storm Sewer System(MS4)name(s)if discharging to a MS4. If stormwater is discharged through a MS4(either partially or completely),provide the name of the MS4(s)that will be receiving water from this construction activity. The MS4 name is typically the town,city, county,institute or federal facility where the construction activity is located. F.This construction activity is part of a common plan of development or sale. "Common plan of development or sale"means a contiguous area where separate and distinct construction activities may be taking place at different times on different schedules per 9VAC25-870-10.Definitions. I.e.a subdivision,commercial development,business park,etc. G.6th Order Hydrologic Unit Code(HUC)and associated Receiving Water Name(s). Provide all 6th order HUCs and receiving waters for the site and offsite areas that could potentially receive stormwater runoff discharging from this activity. The HUC can be either a 12-digit number(i.e. 0208010101)or 2-letter,2-number code(i.e.JL52). Include additional HUCs or receiving waters on a separate page. You may utilize DEQ's web- based GIS application,VEGIS,to obtain this information. • VEGIS application link: DEQ's VEGIS Mapping Application • Instructions for utilizing DEQ's VEGIS application link: CGP-GIS HUC Instructions Rev 04/2019 PAGE 6 17 APPX D- Delegation of Authority Delegation of Authority I, (name), hereby designate the person or specifically described position below to be a duly authorized representative for the purpose of overseeing compliance with environmental requirements, including the Construction General Permit, at the construction site. The designee is authorized to sign any reports or other documents required by the permit. (name of person or position) (company) (address) (city, state, zip) (phone) By signing this authorization, I confirm that I meet the requirements to make such a designation as set forth in Virginia's General VPDES Permit for Discharges of Stormwater from Construction Activities (CGP), and that the designee above meets the definition of a"duly authorized representative" as set forth in in the CGP. I certify under penalty of law that I have read and understand this document and that this document and all attachments were prepared in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Name: Company: Title: Signature: Date: 29 APPX E- Inspection Reports and Precipitation Log (Blank inspection report included below. Weekly inspection reports are found in different folder in SWPPP box) Stormwater Construction Site Inspection Report General.Information Project Name NPDES Tracking No. Location Date of Inspection Start/End Time Inspector's Name(s) Inspector's Title(s) Inspector's Contact Information Inspector's Qualifications Describe present phase of construction Type of Inspection: ❑Regular ❑ Pre-storm event ❑During storm event ❑Post-storm event Yr tither n prmatidn Has there been a storm event since the last inspection? ❑Yes ❑No If yes,provide: Storm Start Date&Time: Storm Duration(hrs): Approximate Amount of Precipitation(in): Weather at time of this inspection? ❑Clear ❑Cloudy ❑ Rain ❑ Sleet ❑Fog ❑ Snowing ❑ High Winds ❑Other: Temperature: Have any discharges occurred since the last inspection? ❑Yes ❑No If yes,describe: Are there any discharges at the time of inspection? ❑Yes ❑No If yes,describe: Site-specific BMPs • Number the structural and non-structural BMPs identified in your SWPPP on your site map and list them below(add as many BMPs as necessary). Carry a copy of the numbered site map with you during your inspections. This list will ensure that you are inspecting all required BMPs at your site. • Describe corrective actions initiated, date completed, and note the person that completed the work in the Corrective Action Log. -Fit ,:BMPN....;ur-"'; =`�= `Corr'ectiveAction°Needeil.arid�N.otes _ ..BMP;, ,.x,3;. •. s�-.�;-:,;;: N - .r Cotiectiveir� "naac :Installed. `1Vlau►te �K��' ~7't1., i-n e uireil 'Act o - ,,;fir_!e�� - F i • Tak 1 ❑Yes ❑No ❑Yes ❑No 2 UYes ❑No ❑Yes ❑No 3 ❑Yes ❑No ❑Yes ❑No 4 ❑Yes ❑No ❑Yes ❑No 5 ❑Yes ❑No ❑Yes ❑No 6 ❑Yes ❑No ❑Yes ❑No 30 BMP BMP BMP Corrective Action Needed and Notes Date Installed? Maintenance • Corrective Required? Action . Taken 7 ❑Yes UNo UYes UNo 8 UYes UNo UYes UNo 9 ❑Yes UNo UYes UNo 10 ❑Yes No ❑Yes UNo 11 ❑Yes No ❑Yes UNo 12 ❑Yes UNo UYes UNo 13 UYes ❑No UYes No 14 UYes UNo UYes UNo 15 UYes No :Wes UNo 16 UYes No ❑Yes UNo 17 UYes ❑No UYes UNo 18 ❑Yes UNo UYes No 19 ❑Yes UNo UYes No 20 ❑Yes UNo UYes ❑No Overall Site Issues Below are some general site issues that should be assessed during inspections. Customize this list as needed for conditions at your site. BMP/activity Implemented? Maintenance Corrective Action Needed and Notes Required? 1 Are all slopes and UYes UNo UYes UNo disturbed areas not actively being worked properly stabilized? 2 Are natural resource UYes No UYes UNo areas(e.g.,streams, wetlands,mature trees, etc.)protected with barriers or similar BMPs? 3 Are perimeter controls ❑Yes UNo UYes No and sediment barriers adequately installed (keyed into substrate) and maintained? 4 Are discharge points and UYes UNo UYes ❑No receiving waters free of any sediment deposits? 5 Are storm drain inlets UYes No ❑Yes UNo properly protected? 6 Is the construction exit ❑Yes UNo UYes UNo preventing sediment from being tracked into the street? 7 Is trash/litter from work ❑Yes UNo UYes ❑No areas collected and placed in covered dumpsters? 31 BMP/activity Implemented? Maintenance Corrective Action Needed and Notes Required? 8 Are washout facilities ❑Yes ❑No ❑Yes ❑No (e.g.,paint,stucco, concrete)available, clearly marked,and maintained? 9 Are vehicle and ❑Yes No ❑Yes ❑No equipment fueling, cleaning,and maintenance areas free of spills, leaks,or any other deleterious material? 10 Are materials that are ❑Yes ❑No ❑Yes ❑No potential stormwater contaminants stored inside or under cover? 11 Are non-stormwater ❑Yes ❑No ❑Yes ❑No discharges(e.g.,wash water,dewatering) properly controlled? 12 (Other) ❑Yes ❑No ❑Yes ❑No Non-Compliance Describe any incidents of non-compliance not described above: CERTIFICATION STATEMENT "I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted.Based on my inquiry of the person or persons who manage the system,or those persons directly responsible for gathering the information,the information submitted is,to the best of my knowledge and belief,true,accurate,and complete.I am aware that there are significant penalties for submitting false information,including the possibility of fine and imprisonment for knowing violations." Print name and title: Signature: Date: 32 Rainfall Documentation: Project: Georgetown Hydraulic ) Source: www.wunderground.com, Stations near Intersection Date Amount of Precipitation (in.). 33 APPX F- Grading and Stabilization Log Grading and Stabilization Activities Log Project Name: Georgetown Hydraulic SWPPP Contact: Date Location Date;Grading`Activity- Date-When ':Description,of Grading of Grading Ceased (Indicate. Stabilization._ _ Stabilization Activity Temporary or` Measures are Measure and Initiated Permanent) Initiated Location 34 APPX G- Log of Changes and Updates to SWPPP SWPPP Amendment Log Project Name: Georgetown Hydraulic SWPPP Contact: Amendment Description of the Amendment _ Date of Amendment No: Amendment Prepared by[Name(s) and Title] 35 APPX H- Subcontractor and Contractor Certifications/Agreements Subcontractor and Contractor Certifications/Agreements SUB/CONTRACTOR CERTIFICATION STORMWATER POLLUTION PREVENTION PLAN Project Title: Operator(s): As a subcontractor, you are required to comply with the Stormwater Pollution Prevention Plan (SWPPP) for any work that you perform on-site. Any person or group who violates any condition of the SWPPP may be subject to substantial penalties or loss of contract. You are encouraged to advise each of your employees working on this project of the requirements of the SWPPP. A copy of the SWPPP is available for your review at the SWPPP mailbox. Each subcontractor engaged in activities at the construction site that could impact stormwater must be identified and sign the following certification statement: I certify under the penalty of law that I have read and understand the terms and conditions of the SWPPP for the above designated project and agree to follow the BMPs and practices described in the SWPPP. This certification is hereby signed in reference to the above named project: Company: Address: Telephone Number: Type of construction service to be provided: Signature: Title: Date: 36 �=/EPA Stormwater Best Management Practice ,�Sfor ch... United States 4 Agen cy Protection Agency Concrete Washout Construction workers should handle wet concrete and Minimum Measure washout water with care because it may cause skin irritation Construction Site Stormwater Runoff Control and eye damage. If the washwater is dumped on the ground Subcategory (Fig. 1), it can run off the construction site to adjoining roads and enter roadside storm drains, which discharge to surface Good Housekeeping/Materials Management waters such as rivers, lakes, or estuaries. The red arrow in Figure 2 points to a ready mixed truck chute that's being Description of Concrete Washout at washed out into a roll-off bin, which isn't watertight. Leaking washwater, shown in the foreground, will likely follow similar Construction Sites Figure 1.Chute Concrete and its ingredients washwater being dumped , +e�•., on the ground Concrete is a mixture of cement,water, and aggregate material. : '. ° Portland cement is made by heating a mixture of limestone and clay containing oxides of calcium, aluminum, silicon and other „g; , '•• metals in a kiln and then pulverizing the resulting clinker.The fine aggregate articles are usually sand. Coarse aggregate is generally gravel or crushed stone. When cement is mixed ` .- with water, a chemical reaction called hydration occurs,which - " ti ° produces glue that binds the aggregates together to make concrete. T. Concrete washout Figure 2.:;hute washwater leaking from a .• After concrete is poured at a construction site,the chutes of roll-off bin being used as a ready mixed concrete trucks and hoppers of concrete pump washout container trucks must be washed out to remove the remaining concrete before it hardens. Equipment such as wheelbarrows and hand paths to nearby surface waters. Rainfall may cause concrete tools also need to be washed down.At the end of each work washout containers that are uncovered to overflow and also day, the drums of concrete trucks must be washed out.This is transport the washwater to surface waters. Rainwater polluted customarily done at the ready mixed batch plants,which are with concrete washwater can percolate down through the usually off-site facilities, however large or rural construction soil and alter the soil chemistry, inhibit plant growth, and projects may have on-site batch plants. Cementitious (having contaminate the groundwater. Its high pH can increase the properties of cement)washwater and solids also come from the toxicity of other substances in the surface waters and using such construction materials as mortar, plaster, stucco, soils. Figures 1 and 2 illustrate the need for better washout and grout. management practices. Environmental and Human Health Impacts Best Management Practice Objectives Concrete washout water (or washwater) is a slurry containing The best management practice objectives for concrete washout toxic metals. It's also caustic and corrosive, having a pH are to (a) collect and retain all the concrete washout water and near 12. In comparison, Drano liquid drain cleaner has a pH solids in leak proof containers, so that this caustic material of 13.5. Caustic washwater can harm fish gills and eyes and does not reach the soil surface and then migrate to surface interfere with reproduction. The safe pH ranges for aquatic life waters or into the ground water, and (b) recycle 100 percent habitats are 6.5—9 for freshwater and 6.5—8.5 for saltwater. of the collected concrete washout water and solids.Another • Office of Water,4203M EPA 833 F-11-006 www.epa.gov/npdes/pubs/concretewashout.pdf February 2012 www.epa.gov/npdes/stormwater/menuofbmps Stormwater Best Management Practice: Concrete Washout )jective is to support the diversion of recyclable materials from contacted to inquire s 0 landfills. Table 1 shows how concrete washout materials can be about any pretreatment recycled and reused. requirements, i.e., the rr National Pretreatment 14 , .i ,___ - _ y g washout materials Standards for Prohibited Table 1-Recycling concrete ...,diliti— i Concrete Washout Materials Dischargers (40CFR 403.5) -. _ _ before discharging the �. Cu' Cu 3 - - °'" CO y washwater to the POTW.C a QJ p1 C CO y t Cu Cu a' ° _ c The washwater can also Uses of Recycled Materials 5 L ut g c i a '' o o Figure 4.Vacuuming washwater out of a Reused to washout additional mixer be retained in the washout washout container for treatment and reuse truck chutes or drums x container and allowed to Reused as a ready mixed concrete x xb x x evaporate, leaving only the hardened cementitious solids to be ingredient Reused as an ingredient of precast j recycled. concrete products,e.g.,highway x x x x ' x barriers,retaining wall blocks,riprap - Solids recycling j Reused as crushed concrete products,e.g.,road base or fill x x x x The course aggregate materials that are washed off concrete Reused to pave the yards of ready I x truck chutes into a washout container can be either separated mixed concrete plants by a screen and placed in aggregate bins to be reused at Returned back to a surface water, xc the construction site or returned to the ready mixed plant and e.g.,river,lake,or estuary a. Fine particles of cementitious material(e.g.,Portland cement,slag cement,fly ash. washed into a reclaimer(Fig. 5). When washed out into a silica fume) reclaimer,the fine and course aggregates are separated out b. Recyclable,if allowed by the concrete quality specifications and placed in different c. Treated to reduce the pH and remove metals;so it can be delivered to a municipal wastewater treatment plant.where it is treated further and then returned to a natural piles or bins to be reused surface water in making fresh concrete. Washwater recycling, treatment, disposal anks t s Reclaimers with settling tanks separate cement Washwater from concrete truck fines from the washwater . $ chutes, hand mixers, or other and these fines can also 'idigimiarill-,99' equipment can be passed through be used in new concrete a system of weirs or filters to remove am solids and then be reused to wash unless prohibited by the gwashing Figure 5.Readymixed truck down more chutes and equipment user's concrete quality out into a reclaimer specifications. at the construction site or as an ingredient for making additional Hardened concrete recycling concrete.A three chamber washout When the washwater in a construction site concrete washout filter is shown in Figure 3.The first container has been removed or allowed to evaporate,the stage collects the coarse aggregate. hardened concrete that remains can be crushed (Fig. 6) The middle stage filters out the Figure 3.Concrete washout and reused as a construction material. It makes an excellent small grit and sand. The third stage filter aggregate for road base and can be used as fill at the has an array of tablets that filter construction site or out fines and reduces the pH.The filtered washwater is then delivered to a recycler. discharged through a filter sock. An alternative is to pump the Concrete recyclers can washout water out of the washout container (Fig 4) and treat ;., be found at municipal the washwater off site to remove metals and reduce its pH, 1 " p k.. �! ; solid waste disposal so it can be delivered to a publicly owned treatment works facilities, private 'DOTW), also known as a municipal wastewater treatment plant, hichprovides additional treatment allowingthe washwater Figure 6.Crushed concrete stockpile and recycling plants, or large crusher construction sites. to be discharged to a surface water.The POTW should be 2 Stormwater Best Management Practice: Concrete Washout Wet concrete recycling driver then washes down Builders often order a little more ready mixed concrete than the chute into the bucket toRV ,I they actually need, so it is common for concrete trucks to remove any cementitious P14 r material before it hardens. -{" , have wet concrete remaining in their drum after a delivery.This -: ,.•• ` ` ` I unused concrete can be returned to the ready mixed plant and After washing out the chute, _ either (1) used topourprecast concreteproducts (e.g., highwaythe driver pumps (yellow barriers, retaining wall blocks, riprap), (2) used to pave the arrow points to the pump) ready mixed plant's yard, (3)washed into a reclaimer, or the washwater, sand, and other fine solids from the Figure 8.Chute NasnJut bucket and (4) dumped on an impervious surface and allowed to harden, pump so it can be crushed and recycled as aggregate. Unused wet bucket up into the truck's concrete should not be dumped on bare ground to harden at drum to be returned to the construction sites because this can contribute to ground water ready mixed plant, where it can be washed into a reclaimer. and surface water contamination. A removable screen at the bottom of the washout bucket prevents course aggregate from entering the pump.This Washout Containers course aggregate can also be returned to the plant and added to the coarse aggregate pile to be reused.All the materials are Different types of washout containers are available for recycled. collecting, retaining, and recycling the washwater and solids from washing down mixed truck chutes and pump truck Hay bale and plastic washout pit hoppers at construction sites. A washout pit made with hay bales and a plastic lining is shown in Figure 9. Such pits can be dug into the ground or built above Chute washout box grade.The plastic lining should be free of tears or holes that A chute washout box is mounted on the back of the ready would allow the washwater to escape (Fig. 10).After the pit is mixed truck. If the truck has three chutes, the following used to wash down the chutes of multiple ready mixed trucks procedure is used to perform the washout from the top down: and the washwater has evaporated or has been vacuumed off, (1) after the pour is completed, the driver attaches the extension the remaining hardened solids can be broken up and removed chute to the washout box, (2) the driver then rotates the main from the pit.This process may damage the hay bales and chute over the extension chute (Fig. 7) and washes down the plastic lining. If damage occurs, the pit will need to be repaired hopper first then the main chute, (3) finally the driver washes and relined with new plastic.When the hardened solids are down the flop down chute and last the extension chute hanging removed, they may be bound up with the plastic lining and have on the box.All washwater and solids are captured in the box. to be sent to a landfill, rather than recycled. Recyclers usually After the wash down, accept only unmixed material. If the pit is going to be emptied �� , '-N washwater and solids are and repaired more than a few times,the hay bales and plastic I i., returned to the ready mixed will be generating additional solid waste. Ready mixed concrete ' '_ plant for recycling.A filter ��.?41 1' ` R „ .. Figure 9,Hay bale and plastic .y " ' basket near the top of the washout pit .> f`lly, ¢ 3 washout box separates out l x 1pthe coarse aggregates so „Y they can be placed in a bin for reuse either at the 0. _ construction site or back at :- ,t ., Figure 7.Chute washout box the cement plant. , Figure 10.Leaking :r ;t' " �r- washout pit that Chute washout bucket and pump ., a,,' has not been well _-� maintained After delivering ready mixed concrete and scraping the last of Iii, � , the customer's concrete down the chute, the driver hangs a _ ._ ' washout bucket shown in Figure 8 (see red arrow) on the end of = the truck's chute and secures the hose to insure no leaks.The 3 Stormwater Best Management Practice: Concrete Washout icks can use hay bale washout pits, but concrete pump subsequent discharge to a surface water. Everything is recycled trucks have a low hanging hopper in the back that may prevent or treated sufficiently to be returned to a natural surface water. their being washed out into bale lined pits. Figure 14.Pump truck using the 1.1111. . ramp to wash out into a roll-off bin Vinyl washout container lit- The _ vinyl washout __ - ' p," - - container(Fig. 11) is . portable, reusable, and easier to install than a ,f t;`�•. Figure 15. hay bale washout pit. Delivering The biodegradable filter hardened Concrete Figure 11.Vinyl washout pit with filter bag _c-'- to a recycler bag (Fig. 12)assists in - ' ,-.:,..;;;: -A - extracting the concrete solids and prolongs the life of the vinyl container.When the bag is lifted, the water is filtered out and r " - ir, the remaining concrete solids and the bag can be disposed of - together in a landfill, or the hardened concrete can be delivered - - 3 to a recycler.After the solids have been removed several times - and the container is full of washwater, the washwater can be allowed to evaporate, so the container can be reused.The Another metal, portable, washout container,which has a washwater can be removed more quickly by placing another rain cover to prevent overflowing, is shown in Figure 16. It is filter bag in the container accompanied by an onsite washwater treatment unit, which and spreading water gelling • reduces the pH and uses a forced weir tank system to remove anules evenly across the the coarse aggregate, fine aggregate, and cement fines. The ater. In about five minutes, •, . ', washwater can the water in the filter bag will then be reused at oitit„ turn into a gel that can be the construction �y removed with the bag.Then (' / site to wash �✓q —�i jar the gel and filter bag can be - , "ct out other mixer - , disposed to together. i truck chutes — ~' ® • ® P 9 Figure 12.Extracting the concrete �� solids or gelled washwater and equipment. Metal washout container Figure 16.Washout container with a rain covet and The solids are onsite washwater treatment The metal roll-off bin (Fig. 13) is designed to securely contain allowed to harden concrete washwater and solids and is portable and reusable. together and can ! i._,,. - It also has a ramp that allows concrete pump trucks to wash be taken to a concrete _ . . _ . out their hoppers (Fig. 14). Roll-off providers offer recycling recycler(Fig. 17)to be _ • services, such as, picking up the roll-off bins after the crushed and used as • t .. ' -- washwater has evaporated and the solids have hardened, road base or aggregate , `a. replacing them with for making precast 1 empty washout bins, and - ._, products, such as delivering the hardened .'=- retaining wall blocks.All Figure 17.Delivering hardened concrete i concrete to a recycler s•4i; :A materials are recycled. to a recycler (Fig. 15), rather than a ,. landfill. Some providers will • • "- : -s- Siting Washout Facilities vacuum off the washwater, f -- 9 _y, 1 i Concrete washout facilities, such as washout pits and vinyl treat it to remove metals and `'tt or metal washout containers, should be placed in locations duce the pH, deliver it to a - that provide convenient access to concrete trucks, preferably ..astewater treatment plant Figure 13.Mixer truck being washed out near the area where concrete is being poured. However they for additional treatment and into a roll-off bin 4 Stormwater Best Management Practice: Concrete Washout should not be placed within 50 feet of storm drains, open Reference ditches, or waterbodies.Appropriate gravel or rock should cover approaches to concrete washout facilities when they are NRMCA 2009. Environmental Management in the Ready located on undeveloped property. On large sites with extensive Mixed Concrete Industry, 2PEMRM, 1st edition. By Gary M. concrete work,washouts should be placed at multiple locations Mullins. Silver Springs, MD: National Ready Mixed Concrete for ease of use by ready mixed truck drivers. If the washout Association. facility is not within view from the pour location, signage will be needed to direct the truck drivers. Websites and Videos Construction Materials Recycling Association Operating and Inspecting Washout www.concreterecycling.org Facilities Concrete washout facilities should be inspected daily and after National Ready Mixed Concrete Association heavy rains to check for leaks, identify any plastic linings and www.nrmca.org sidewalls have been damaged by construction activities, and determine whether they have been filled to over 75 percent National Ready Mixed Concrete Research and Education capacity.When the washout container is filled to over Foundation 75 percent of its capacity,the washwater should be vacuumed www.rmc-foundation.org off or allowed to evaporate to avoid overflows.Then when the Additional information and videos on concrete washout remaining cementitious solids have hardened, they should be containers and systems can be found by a web search for removed and recycled. Damages to the container should be "concrete washout." repaired promptly. Before heavy rains, the washout container's liquid level should be lowered or the container should be covered to avoid an overflow during the rain storm. Photograph Credits Figures 1,2.Mark Jenkins, Concrete Washout Systems,Inc. Educating Concrete Subcontractors Figure 3.Mark Shaw, Ultra Tech International, Inc. Figure 4.Mark Jenkins, Concrete Washout Systems, Inc. The construction site superintendent should make ready mixed Figure 5.Christopher Crouch, CC/Consulting truck drivers aware of washout facility locations and be watchful Figure 6.William Turley, Construction Materials Recycling Association for improper dumping of cementitious material. In addition, Figure 7.Brad Burke, Innovative Concrete Solutions,LLC concrete washout requirements should be included in contracts Figure 8.Ron Lankester, Enviroguard with concrete delivery companies. Figures 9, 10.Mark Jenkins, Concrete Washout Systems,Inc. Figures 11, 12.Tom Card, RTC Supply Figures 13, 14, 15.Mark Jenkins,Concrete Washout Systems,Inc. Figures 16, 17.Rick Abney Sr., Waste Crete Systems, LLP Disclaimer Please note that EPA has provided external links because they provide additional information that may be useful or interesting.EPA cannot attest to the accuracy of non-EPA information provided by these third-party websites and does not endorse any non-government organizations or their products or services. 5 Procedure for Spills of Non-Reportable Quantities Most spills can be cleaned up following manufacturer specifications. Absorbent/oil dry, sealable containers, plastic bag and shovels/brooms are suggested minimum spill response items that should be available at this location. 1) Check for hazards (flammable material, noxious fumes, cause of spill)-if flammable liquid, turn off engines and nearby electrical equipment. If serious hazards are present, leave the area and call 911. 2) Make sure the spill area is safe to enter and that it does not pose an immediate threat to health or safety of any person. 3) Stop the spill source. 4) Call co-workers and supervisor for assistance and to make them aware of the spill and potential dangers. 5) If possible, stop spill from entering drains (use absorbent or other material as necessary) 6) Stop spill from spreading(use absorbent or other material) 7) If spill material has entered a storm sewer; contact locality's storm sewer water department and locality's VSMP inspector. 8) Clean up spilled material and do not flush area with water. 9) Properly dispose of cleaning materials and used absorbent material according to manufacturer specifications. Spill Report Form Project Type and Location: Date/Time of Spill: Time Incident Contained: Spill Location and Events leading to Spill: Material Spilled: Source of Spill: Amount Spilled: Amount Spilled to Waterway: Surface Area of Impacted Media in Sq.ft.: Type of Media (Soil or Pavement): Corrective Action Taken: Action Taken to Prevent Future Spills: Agencies Notified: Modifications of Storm Water Pollution Prevention Plan: "I certify under penalty of law that I have read and understand this document and that this document and all attachments were prepared in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system,or those persons directly responsible for gathering the information,the information submitted is,to the best of my knowledge and belief,true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." Print Name/Title of Reporter: Signature: Date: Company: 1992 3.38 STD & SPEC 3.38 TREE PRESERVATION v , & PROTECTION TP Definition Protection of desirable trees from mechanical and other injury during land disturbing and construction activity. Purpose To ensure the survival of desirable trees where they will be effective for erosion and sediment control,watershed protection,landscape beautification, dust and pollution control, noise reduction, shade and other environmental benefits while the land is being converted from forest to urban-type uses. • Conditions Where Practice Applies Tree-inhabited areas subject to land disturbing activities. , • • < a_ .; = a4r yx"n,-,;- µ d'a '' ' it f4 fir . -a • = 4. � .r,M „ ,• .'' ,.„ ;p y � i . . i, )'r X2. `a 4 i Y T, M� j . f's` ; . P . J '-- ', •` ia. ' 4 a,:: Y ' • \'''', 7,c`'., .., r.� •��.o*, ram;,, „• $ ,I. ,; !''.•x .,,&C4W,t.•;. ,. ' '^a7, ,'�. "fir, w ^.•t, ae'::7-F'^.W+,,.y` .11 -,.,. ",'`�Y'§."s;;f.—' "' 'sue '''' 1f '. h`-:.£..i', ' S .$ $.°."e'%,.., ''' —.7 b. it Fe :4 .. :mow:;.F'}.�\ F- 3 1a' �i �" b+ �;j�'f ,� g. •.}-.y ... .y•. -'a v4 s.C*P�,s+•'� '` x *�, .a+vk .ffi�� � ' �` `".��aR • t` ..* 3^ :'i.. .k'w-' br 1��,N�.-`� 3 f4 ".Y . p , a•. R'Y $ e K�" a. yaw„"' ',Y'„ 4•5.,„ L !} , s...r.- p,'t : 4. 1. � �` :-•r, '- y fF5" ' t,.Ac,P¢'N" ''�'!°'R!^ yam, S'sC °'' r .0 ,... 1_ •k. �"� q `,yae'°f� 'E'n,,�.a., x>::�i x'xe 'x 3 <"�.'7 � . W. .,.+v,,. . .wv-1 C'.aT®S`:- ,ti. x*t ., T^"4;'t r nfi 0 "..y " 19 'cam'."' '� . + :. ''' is c �.'w-..«==«.,+ -.,, ," ,„r";,,,.,.,. .,� ""=7.1* ,-,''"'. as�.,�,.. -"�.rim"''-�'�',.,.1,•,.�.»...z;,•,•.,-::,�:'.::„..„;;..N - j. 76 . :y III - 393 1992 3.38 Planning Considerations New development often takes place on tracts of forested land. In fact, building sites are often selected because of the presence of mature trees. However, unless sufficient care is taken and planning done in the interval between buying the property and completing construction, much of this resource is likely to be destroyed. The property owner is ultimately responsible for protecting as many trees as possible, with their understory and ground cover. This responsibility is usually exercised by agents-the planners, designers and contractors. It takes 20 to 30 years for newly planted trees to provide the benefits for which we value trees so highly. Trees perform the following functions on a site: 1. Assist in stabilizing the soil and preventing erosion. 2. Help to decrease stormwater runoff through canopy interception and root zone absorption. 3. Moderate temperature changes and provide shade. 4. Moderate the effects of sun and wind. 5. Provide buffers and screens against noise. 6. Filter pollutants from the air. 7. Help to remove carbon dioxide from the air and release oxygen. 8. Provide a haven for animals and birds, which help to control insect populations. 9. Conserve and increase property values. 10. Provide psychological and aesthetic counterpoints to the man-made urban setting. Stresses of Construction Trees may appear to be inanimate objects, but they are living organisms that are constantly involved in the process of respiration, food processing, and growth. Construction activities expose trees to a variety of stresses resulting in injury ranging from superficial wounds to death. An understanding of these stresses is helpful in planning for tree protection. 1. Surface Impacts: Natural and man-related forces exerted on the tree above the ground can cause significant damage to trees. a. Wind damage - Removal of some trees from groups will expose those remaining to greater wind velocities. Trees tend to develop anchorage where III - 394 1992 3.38 it is most needed. Isolated trees develop anchorage rather equally all around, with stronger root development on the side of the prevailing winds. The more a tree is protected from the wind, the less secure is its anchorage. The result of improper thinning is often wind-thrown trees. Selective removal in favor of a single tall tree may also create a lightning hazard. b. Excessive pruning-Unprotected trees are often"topped" or carelessly pruned to prevent interference with utility wires or buildings. If too many branches are cut, the tree may not be able to sustain itself. If the pruning is done without considering the growth habit, the tree may lose all visual appeal. If the branches are not pruned correctly, decay may set in. c. Trunk damage - Tree trunks are often nicked or scarred by trucks and construction equipment. Such superficial wounds provide access to insects and disease. 2. Root Zone Impacts: Disturbing and delicate relationship between soil,roots,and the rest of the tree can damage or kill a tree. The roots of an existing tree are established in an area where essential materials (water, oxygen, and nutrients) are present. The mass of the root system is the correct size to balance the intake of water from the soil with the transpiration of water from the leaves. a. Raising the grade as little as 6 inches can retard the normal exchange of air and gases. Roots may suffocate due to lack of oxygen, or be damaged by toxic gases and chemicals released by soil bacteria. - b. Raising the grade may also elevate the water table. This can cause drowning of the deeper roots. c. Lowering the grade is not usually as damaging as raising it. However, even shallow cuts of 6 to 8 inches will remove most of the topsoil, removing some feeder roots and exposing the rest to drying and freezing. d. Deep cuts may sever a large portion of the root system, depriving the tree of water and increasing the chance of wind-throw. e. Lowering the grade may lower the water table, inducing drought. This is a problem in large roadway cuts or underdrain installations. f. Trenching or excavating through a tree's root zone can eliminate as much as 40 percent of the root system. Trees suffering such damage usually die within 2 to 5 years. g. Compaction of the soil within the drip line (even a few feet beyond the drip line) of a tree by equipment operation, materials storage, or paving can block off air and water from roots. III - 395 1992 3.38 h. Construction chemicals or refuse disposed of in the soil can change soil chemistry or be toxic to trees. Most damage to trees from construction activities is due to the invisible root zone stresses. Design Criteria No formal design is required. However, in planning for the development of a wooded site where some trees will be preserved, a number of criteria must be considered. Selecting Trees to be Retained The proper development of a wooded site requires completion of a plan for tree preservation before clearing and construction begins. Trees should be identified by species, and located on a topographical map, either as stands or as individuals, depending on the density and value of the trees. Base decisions on which trees to save on the following considerations: 1. Life expectancy and present age: Preference should be given to trees with a long life span, such as white oak, beech, and maple. Long-lived specimens that are past their prime may succumb to the stresses of construction, so smaller, younger trees of desirable species are preferred; they are more resilient and will last longer. However, if the cost of preservation is greater than the cost of replacement with a specimen of the same age and size, replacement may be preferred. 2. Health and disease susceptibility: Check for scarring caused by fire or lightning, insect or disease damage, and rotted or broken trunks or limbs. Pest- and pollution-resistant trees are preferred. 3. Structure: Check for structural defects that indicate weakness or reduce the aesthetic value of a tree: trees growing from old stumps, large trees with overhanging limbs that endanger property, trees with brittle wood (such as silver maple), misshapen trunks or crowns, and small crowns at the top of tall trunks. Open grown trees often have better form than those grown in the woods. Trees with strong tap or fibrous root systems are preferred to trees with weak rooting habits. 4. Cleanliness: Some trees such as elm and black locust are notoriously "dirty", dropping twigs,bark,fruit, or plant exudates. A clean tree is worth more than a dirty one. Trees which seed prolifically or sucker profusely are generally less desirable in urban areas. Thornless varieties are preferred. 5. Aesthetic values: Handsome bark and leaves, neat growth habit, fine fall color, and attractive flowers and fruit are desirable characteristics. Trees that III - 396 1992 3.38 provide interest during several seasons of the year enhance the value of the site. 6. Comfort: Trees help relieve the heat of summer and buffer strong winds throughout the year. Summer temperatures may be 10 degrees cooler under hardwoods than under conifers. Deciduous trees drop their leaves in winter, allowing the sun to warm buildings and soil. Evergreens are more effective wind buffers. 7. Wildlife: Preference should be given to trees that provide food, cover, and nesting sites for birds and game. 8. Adaptability to the proposed development: a. Consider the mature height and spread of trees; they may interfere with proposed structures and overhead utilities. Roots may interfere with walls,walks, driveways, patios, and other paved surfaces; or water lines, septic tanks, and underground drainage. b. Trees must be appropriate to the proposed use of the development; select trees which are pollution-tolerant for high-traffic and industrial areas, screen and buffer trees for noise or objectionable views, salt- tolerant species for areas exposed to deicing salts or ocean spray. c. Consider location of landfills. Gases generated in them can travel long distances underground,to injure distant trees. Choose species tolerant of anaerobic soil conditions. d. Determine the effect of proposed grading on the water table. Grading should not take place within the drip line of any tree to be saved. 9. Survival needs of the tree: Chosen trees must have enough room to develop naturally. They will be subject to injury from increased exposure to sunlight, heat radiated from buildings and pavement, and wind. It is best to retain groups of trees rather than individuals. As trees mature, they can be thinned gradually. 10. Relationship to other trees: Individual species should be evaluated in relation to other species on the site. A species with low value when growing among hardwoods will increase in value if it is the only species present. Trees standing alone generally have higher landscape value than those in a wooded situation. However, tree groups are much more effective in preventing erosion and excess stormwater runoff. III - 397 1992 3.38 Site Planning for Tree Protection 1. If lot size allows, select trees to be saved before siting the building. No tree should be destroyed or altered until the design of buildings and utility systems is final. 2. Critical areas, such as flood plains, steep slopes, and wetlands, should be left in their natural condition or only partially developed as open space. 3. Locate roadways to cause the least damage to valuable stands. Follow original contours, where feasible, to minimize cuts and fills. 4. Minimize trenching by locating several utilities in the same trench. Excavations for basements and utilities should be kept away from the drip line of trees. 5. Construction material storage areas and worker parking should be noted on the site plan, and located where they will not cause compaction over roots. 6. When retaining existing trees in parking areas, leave enough ground ungraded beyond the drip line of the tree to allow for its survival. 7. Locate erosion and sediment control measures at the limits of clearing and not in wooded areas, to prevent deposition of sediment within the drip line of trees being preserved. Sediment basins should be constructed in the natural terrain, if possible, rather than in locations where extensive grading and tree removal will be required. Specifications 1. Groups of trees and individual trees selected for retention shall be accurately located on the plan and designated as "tree(s) to be saved." Individual specimens that are not part of a tree group shall also have their species and diameter noted on the plan. 2. At a minimum, the limits of clearing shall be located outside the drip line of any tree to be retained and, in no case, closer than 5 feet to the trunk of any tree (Plate 3.38- 1). 3. Marking: Prior to construction and before the preconstruction conference,individual trees and stands of trees to be retained within the limits of clearing shall be marked at a height visible to equipment operators. According to the Virginia Department of Forestry, a diagonal slash of brightly colored paint approximately 8 to 10 inches in length is a common practice in areas where an accidental or purposeful alteration of the proper markings is a concern. In most situations, such as an area which is supposed to receive formal landscaping, a surveyor's ribbon or a similar material applied at a reasonable height encircling the tree will suffice. III - 398 1992 3.38 tettlliVrair"' iiiiifte � Noore i '+" DRIP LINE _� 40 l d[.� j�11 144, lb t10il 4 illy i PROTECTNE DEVICE +^'+�1 •' l �t .4111 MAXIMUM LIMITS OF I 'NIP CLEARING AND GRADING PROPOSED GRADING M Aw Ni r .ors lullr'1 r •r MIN. 5' ,' is �' � WHERE DRIPLINE IS LESS THAN 5' s� CONSTRUCTION OPERATIONS RELATIVE TO THE LOCATION OF PROTECTED TREES Source: Public Facilities Manual, Vol. III, Fairfax Co., Va., 1976 Plate 3.38-1 4. Pre-Construction Conference: During any preconstruction conference, tree preservation and protection measures should be reviewed with the contractor as they apply to that specific project. 5. Equipment Operation and Storage: Heavy equipment,vehicular traffic, or stockpiles of any construction materials (including topsoil) shall not be permitted within the drip line of any tree to be retained. Trees being removed shall not be felled,pushed or pulled into trees being retained. Equipment operators shall not clean any part of their equipment by slamming it against the trunks of trees to be retained. 6. Fires: Fires shall not be permitted within 100 feet from the drip line of any trees to be retained. Fires shall be limited in size to prevent adverse effects on trees, and kept under surveillance. 7. Storage and Disposal of Toxic Materials: No toxic materials shall be stored closer than 100 feet to the drip line of any trees to be retained. Paint, acid, nails, gypsum board, wire, chemicals, fuels, and lubricants shall not be disposed of in such a way as to injure vegetation. III - 399 1992 3.38 8. Fencing and Armoring (Plate 3.38-2): Any device may be used which will effectively protect the roots, trunk and tops of trees retained on the site. However, trees to be retained within 40 feet of a proposed building or excavation shall be protected by fencing. Personnel must be instructed to honor protective devices. The devices described are suggested only, and are not intended to exclude the use of other devices which will protect the trees to be retained. a. Snow Fence - Standard 40-inch high snow fence shall be placed at the limits of clearing on standard steel posts set 6 feet apart. b. Board Fence - Board fencing consisting of 4-inch square posts set securely in the ground and protruding at least 4 feet above the ground shall be placed at the limits of clearing with a minimum of two horizontal boards between posts. If it is not practical to erect a fence at the drip line, construct a triangular fence nearer the trunk. The limits of clearing will still be located at the drip line, since the root zone within the drip line will still require protection. c. Cord Fence - Posts with a minimum size of 2 inches square or 2 inches in diameter set securely in the ground and protruding at least 4 feet above the ground shall be placed at the limits of clearing with two rows of cord 1/4-inch or thicker at least 2 feet apart running between posts with strips of colored surveyor's flagging tied securely to the string at intervals no greater than 3 feet. d. Plastic Fencing-40-inch high"international orange"plastic(polyethylene)web fencing secured to conventional metal "T' or "U" posts driven to a minimum depth of 18 inches on 6-foot minimum centers shall be installed at the limits of clearing. The fence should have the following minimum physical qualities: Tensile yield: Average 2,000 lbs.per 4-foot width(ASTM D638) Ultimate tensile yield: Average 2,900 lbs.per 4-foot width(ASTM D638) Elongation at break (%): Greater than 1000% (ASTM D638) Chemical resistance: Inert to most chemicals and acids e. Earth Berms - Temporary earth berms shall be constructed according to specifications for a TEMPORARY DIVERSION DIKE (Std. & Spec. 3.9) with the base of the berm on the tree side located along the limits of clearing. Earth berms may not be used for this purpose if their presence will conflict with drainage patterns. III - 400 1992 3.38 _ 1 FENCING AND ARMORING c-INF-7 \ N._ „,ic..,, `� I „b.* it DRIP LINE I �� < I yb4.,r4 . I SNOW FENCE 1411111111ftk14-irgelkill I I / III•.11.1 I.,.:�.!,I,!uIII. " j1' '1 .eI 141LIN4LI:'sr' ' , Pg.II '14,%4,, °II I 1 • - eiiti:411iiiiii'— . 1001 ........................:............... ..I•L 114 iii it 1 • BOARDlik, FENCE o..•:::❖::❖:❖:•'iiii•••::•••.:�•'i pH, . 1 r ..... .... ....,. CORD FENCE _ PLASTIC FENCE CORRECT METHODS OF TREE FENCING i\NA,\ 1 I+�,,I lam•--- , r't\i ( Ilrell'Irill . Oat 011f 1 :..4.40,...„,,„„par • ;Doi .,,„,,, .... .....„ r CORRECT TRUNK ARMORING r ivA TRIANGULAR BOARD FENCE Source: Va. DSWC Plate 3.38-2 . III - 401 1992 3.38 f. Additional Trees - Additional trees may be left standing as protection between the trunks of the trees to be retained and the limits of clearing. However,in order for this alternative to be used, the trunks of the trees in the buffer must be no more than 6 feet apart to prevent passage of equipment and material through the buffer. These additional trees shall be reexamined prior to the completion of construction and either be given sufficient treatment to ensure survival or be removed. g. Trunk Armoring - As a last resort, a tree trunk can be armored with burlap wrapping and 2-inch studs wired vertically no more than 2 inches apart to a height of 5 feet encircling the trunk. If this alternative is used, the root zone within the drip line will still require protection. Nothing should ever be nailed to a tree. Fencing and armoring devices shall be in place before any excavation or grading is begun, shall be kept in good repair for the duration of construction activities, and shall be the last items removed during the final cleanup after the completion of the project. - 9. Raising the grade: When the ground level must be raised around an existing tree or tree group,the following considerations shall be made and steps taken to adequately care for the affected tree. a. A well may be created around the tree(s) slightly beyond the drip line to retain the natural soil in the area of the feeder roots (Plate 3.38-3). TREE WELL -► „t 4►; •1 ,4 •A'"=ffu►;40"`1 ``;:;;fi:lt1: a%, \ y f t.44;41.;41 rb), lytkik p41 ORIGINAL ' ! ti '14/ 1♦� • ' A.0 i +1 DRIP LINE GRADE I 1 i v�� RETAINING '�� FINISHED GRADE WALL Source: Va. DSWC Plate 3.38-3 III - 402 1992 3.38 b. In the case of an individual tree, when the above alternative is not practical or desirable, the following method is recommended to ensure survival of the tree (Plate 3.38-4). 1) Before making the fill, remove the green vegetation, sod, leaf litter, and other organic matter from beneath the tree or trees to a distance of 3 feet beyond the drip line and loosen the surface soil to a depth of approximately 3 inches without damaging the roots. 2) Apply fertilizer in the root area of the tree to be retained. Fertilizer formulations and application rates and methods shall conform to the guidelines provided in Table 3.38-A. 3) The dry well shall be constructed so as to allow for tree trunk diameter growth. A space of at least 1 foot between the tree trunk and the well wall is adequate for large, old, slow-growing trees. Clearance for younger trees shall be at least 2 feet. 4) The well shall be high enough to bring the top just above the level of the proposed fill. The well wall shall taper slightly away from the tree trunk at a rate of 1 inch per foot of wall height. 5) The well wall shall be constructed of large stones, brick, building tile, concrete blocks, or cinder blocks with care being taken to ensure that - ample openings are left through the wall of the well to allow for free movement of air and water. Mortar shall only be used near the top of the well and only above the porous fill. 6) Drain lines composed of 4-inch, high-quality drain tiles shall begin at the lowest point inside the well and extend outward from the tree trunk in a wheel-and-spoke pattern with the trunk as the hub. These radial drain lines shall slope away from the well at a rate of 1/8 inch per foot. The circumferential line of tiles should be located beneath the drip line of the tree. Vertical tiles or pipes shall be placed over the intersections of the two tile systems if a fill of more than 2 feet is contemplated. These vertical tiles shall be held in place with stone fill. Tile joints shall be tight. A few radial tiles shall extend beyond each intersection and shall slope sharply downward to ensure good drainage. 7) Tar paper or its approved equivalent shall be placed over the tile and/or pipe joints to prevent clogging, and large stone shall be placed around and over drain tiles and/or pipes for protection. III - 403 1992 3.38 TREE WELL DETAIL �r•- i �k. tlio TILE DRAINS -..-- rrt ara�, 4 4"It 1 1�I�N- VERTICAL DRAIN 001111F Ilak..4040.,.. \ lig: •� . • f . Nils . 46464:46•44, ig rift 40.40/ . 11°'.. 4111e'llboi, lii DRIP UNE \\vie' ��� liIry Not FILL SOIL '► �Ir . STRAW OR 412 .1 FILTER FABRIC FILL WITH SAND & CRUSHED CHARCOAL FILL WITH STONE SMALL STONE 1=li_'-: •+.' g ;_.:...'a t ', ' LARGE STONE • i ii n i r 5; =M .�.__..xsa�:4•.'/y �.L��ri�l•�1.1 as-�:— n i _ )RK Nr� . ,.y.�X► _ ,�=1-1=1 1 =II rill=.11=1-I ��. :� GRADE a•:_- II.=II=II=II=II=II '=11=11=11=11=11=11=1i i=" TAR PAPER =CA1-I1=11=11=--11= - ,II ziII=I1=II=II=II= I1=11--11=11.=11. 1 '"-A_-II.II= TILE DRAIN Source: Adapted from Tree Maintenance, 5th ed., Pirone, 1978. Plate 3.38-4 III - 404 TABLE 3.38-A TREE FERTILIZATION FOR PROTECTION FROM CONSTRUCTION ACTIVITY TREE TYPE SPECIAL CONDITIONS APPLICATION RATE & METHOD FORMULATION Normal 2-4 lbs. per inch dbh; Commercial 10-8-6 or 10- Greater than 6 inches dbh* except American broadcast 6-4 Beeches and Crabapples Broad-Leaf Grade 4-5 lbs. per inch dbh; Commercial 10-6-4 Deciduous Change broadcast Normal 1-2 lbs. per inch dbh; Commercial 10-8-6 or 10- Smaller than 6 inches dbh, including all broadcast 6-4 American Beeches and Crabapples Grade 2-3 lbs. per inch dbh; Commercial 10-6-4 Change broadcast Greater than 6 inches dbh, located in groups 2-4 lbs per 100 sq. ft. of bed area; Commercial 10-6-4 broadcast o Narrow-Leaf Evergreen Greater than 6 inches dbh, single specimens 2 lbs. per inch dbh; broadcast Commercial 10-6-4 in open area Smaller than 6 inches dbh 5 lbs. per 100 sq. ft. of bed area; Tankage or Cottonseed incorporated into soil Meal Where nitrogen in soil is sufficient Liberal quantities incorporated into soil Acid Peat Moss or Rotted Broad-leaf Evergreen and applied as mulch Oak Leaf Mold Where additional nitrogen is necessary Also add 5 lbs. per 100 sq. ft. of bed Tankage or Cottonseed area incorporated into soil Meal * dbh : Diameter at breast height (4.5 feet above ground level). w 00 Source: Information taken from Tree Maintenance, P. P. Pirone, 1978. \ j 1992 3.38 8) A layer of 2- to 6-inches of stone shall be placed over the entire area under the tree from the well outward at least as far as the drip line. For fills up to 2-feet deep, a layer of stone 8- to 12-inches thick should be adequate. A thicker layer of this stone, not to exceed 30 inches, will be needed for deeper fills. 9) A layer of 3/4-inch to 1-inch stone covered by straw, fiber-glass mat or a manufactured filter fabric shall be used to prevent soil from clogging the space between stones. Cinders shall not be used as fill material. 10) Filling shall be completed with porous soil such as topsoil until the desired grade is reached. This soil shall be suitable to sustain specified vegetation. 11) To prevent clogging of the drain lines, crushed stone shall be placed inside the dry well over the openings of the radial tiles. Vertical tiles shall also be filled with crushed rock and may also be covered with a screen. 12) To prevent anyone from falling into the dry well and leaves and debris from accumulating there, the area between the trunk and the well wall shall either be covered by an iron grate or filled with a 50-50 mixture of crushed charcoal and sand. (This will also prevent rodent infestation and mosquito breeding.) c. Where water drainage through the soil is not a problem, coarse gravel in the fill may be substituted for the tile. This material has sufficient porosity to ensure air drainage. Instead of the vertical tiles or pipes in the system, stones, crushed rock, and gravel may be added so that the upper level of these porous materials slants toward the surface in the vicinity below the drip line (Plate 3.38-5). d. Raising the grade on only one side of a tree or group of trees may be accomplished by constructing only half of one of these systems. 10. Lowering the grade: Trees shall be protected from harmful grade cuts by the construction of a tree wall (Plate 3.38-6). a. Following excavation, all tree roots that are exposed and/or damaged shall be trimmed cleanly, painted with tree paint, and covered with moist peat moss, burlap, or other suitable material to keep them from drying out. b. The wall shall be constructed of large stones, brick, building tile, or concrete block or cinder block in accordance with the detail in Plate 3.38-6. III - 406 1992 3.38 TREE WELL WITHOUT DRAIN TILES 3;74l,•— sj .1l4•C' Li I<'+1y f.�6,.e �.e _• ? (-3✓i _oaf t l ��'bn is t• C,s yt,9:�. .+��ywc�t` #�' `• z�;r`.= y> ►jay DRIP UNE 1,1 0 0. • �1 io �4 a � t�ti r ►. • gam'; � yvs, 7 , .•• 4$ a err * 1 tar—; • • NEW GRADE STRAW OR FILTETR FABRIC FILL WITH SAND & FILL SOIL r, +• l� CRUS HED CHARCOAL , • I t,�_`�y�`:^4•7: 4 firer _:`;+,�.��j 7f • •.':•.. COARSE ORIGINAL I1�z :.`�•.-_, ^� 2 r�ri��. !_� GRAVEL GRADE : • IV=%i!_:r . i .y'_. .W�' . a :'..!,t. t'i it^i. `•: .•',•i�:+:.'[w:y..r:4:.:< Y ''r.••• •'1:-•pia: .f •.•':a::' '.-'l:gt` x+ptigt:.q.4�L, i'etsr•:;e:a°;5( 'a. •.: �i 1L:L4 � t i 4- :11,:;�,Fie .0 �;_7 AIN Source: Va. DSWC Plate 3.38-5 c. Backfill with peat moss or other organic material or with topsoil to retain moisture and aid in root development. d. Apply fertilizer and water thoroughly. Fertilizer formulations and application rates and methods shall conform to the guidelines provided in Table 3.38-A. e. Prune the tree crown, reducing the leaf surface in proportion to the amount of root loss. f. Provide drainage through the wall so water will not accumulate behind the wall. g. Lowering the grade on only one side of a tree or group of trees may be accomplished by constructing only half of this system. III - 407 • 1992 3.38 TREE WALL DETAIL 164" ,,4 AAA iI vmt,to*� + a/ fir!: �_ illieeA4*--111111fi Mir ..N '���11;i ,I�rli r 41140,0ill, � 1 , �IIL r� tiltlisu DRIP UNE I tt 1 ' -• — i1W"lit+�liy iti / ORIGINAL I I GRADE RETAINING I WALL -JI.�11=11=11=11=11 IIMIIAIIAII II=II=11=I1=11=11PII*Iti►l NEW !!=11 11 II II 1111=11=11=11=11=11 11tiII 11011=11=11=�+ GRADE ° ! = W vr"-"H= =1WORI=1Ir0If*If=11=71= =71=111=H*P • �11*rt ! 11 II II �1--`III--�II—II�--II�--1I�--I� 1� I� �I �I--mII--III* -rr�r II ll 111E I--II II II II I_L II 11�II—�I�I--III,--II II 11 II II—III—III11101III—il I 1W11=11=11 .11 11 II. 11.,11.- 1.=11=11=11=11 .11 II II. 11.=11=11=11=11=1 UNE OF MINIMUM EXCAVATION FOR 5' MIN. h WALL CONSTRUCTION (DRIP UNE) TOPSOIL BACKFILL I I I -11 III I IIIIII-1 I r_Y n � I GRAVEL FILL ,011:I� I MOWHN_ I 1 III III- I I-_III-III 2'--I I I I I-I 1.104°I-I HIGH Wir TAPER WA L L _I �o I�kip '�' TILE DRAIN k41 ,rI • NOTE: ROOTS PENETRATING BEYOND THE WALL LOCATION SHOULD BE BRIDGED 30" MIN. _ii - Source: Adapted from Trees for Architecture and the Landscape, Zion, 1968. Plate 3.38-6 III - 408 , 1992 3.38 11. Trenching and Tunnelling: a. Trenching shall be done as far away from the trunks of trees as possible, preferably outside the branches or crown spreads of trees, to reduce the amount of root area damaged, or killed by trenching activities. b. Wherever possible, trenches should avoid large roots or root concentrations. This can be.accomplished by curving the trench or by tunnelling under large roots and areas of heavy root concentration. c. Tunnelling is more expensive initially, but it usually causes less soil disturbance and physiological impact on the root system (Plate 3.38-7). The extra cost may offset the potential cost of tree removal and replacement should the tree die. TRENCHING VS. TUNNELING -�~ 18" MIN. vv, s IOW • \kip q ....• ... /41 DESTRUCTION OF FEEDER ROOTS TUNNELING UNDER THE TREE WILL WILL PROBABLY KILL THE TREE PRESERVE IMPORTANT FEEDER ROOTS Source: Tree Maintenance, Pirone, 1979. Plate 3.38-7 - III - 409 1992 3.38 Tunnelling is almost always preferred over the trenching method. The tunnel should be 18 inches or greater below the ground surface and should not be located under the center of the tree (an off-center tunnel has the least impact on the roots). d. Roots shall not be left exposed to the air. They shall be covered with soil as soon as possible or protected and kept moistened with wet burlap or peat moss until the trench or tunnel can be filled. e. The ends of damaged and cut roots shall be cut off smoothly and protected by painting promptly with a tree-wound dressing. f. Trenches and tunnels shall be filled as soon as possible. Air spaces in the soil shall be avoided by careful filling and tamping. g. Peat moss or other suitable material shall be added to the fill material as an aid to inducing and developing new root growth. h. The tree shall be mulched and fertilized to conserve moisture, stimulate new root growth, and enhance general tree vigor. i. If a large amount of the root system has been damaged and killed, the crown leaf surface shall be proportionately reduced to balance the reduced root system. This may be accomplished by pruning 20 to 30 percent of the crown foliage. If roots are cut during the winter, pruning shall be accomplished before the next growing season. If roots are cut during the growing season, pruning shall be done immediately. 12. Removal and Replacement of Damaged Trees: Should a tree intended and marked to be retained be damaged seriously enough that survival and normal growth are not possible, the tree shall be removed. If replacement is desirable and/or required,the replacement tree shall be of the same or similar species, 2-inch to 2 2-inch (minimum) caliper balled and burlapped nursery stock. However,today,with the aid of a "tree spade," the same caliper tree may be required as a replacement. 13. Clean-Up: Clean-up after a construction project can be a critical time for tree damage. Trees protected throughout the development operation are often destroyed by carelessness during the final clean-up and landscaping. Fences and barriers shall be removed last, after everything else is cleaned-up and carried away. 14. Maintenance: In spite of precautions, some damage to protected trees may occur. In such cases, the following maintenance guidelines should be followed: a. Soil Aeration - If the soil has become compacted over the root zone of any tree, the ground shall be aerated by punching holes with an iron bar. The bar shall be driven 1-foot deep and then moved back and forth until the soil is IlI - 410 1992 3.38 loosened. This procedure shall be repeated every 18 inches until all of the compacted soil beneath the crown of the tree has been loosened. b. Repair of Damage 1) Any damage to the crown, trunk, or root system of any tree retained on the site shall be repaired immediately. 2) Whenever major root or bark damage occurs, remove some foliage to reduce the demand for water and nutrients. 3) Damaged roots shall immediately be cut off cleanly inside the exposed or damaged area. Cut surfaces shall be painted with approved tree paint, and moist peat moss, burlap, or top-soil shall be spread over the exposed area. 4) To treat bark damage, carefully cut away all loosened bark back into the undamaged area, taper the cut at the top and bottom, and provide drainage at the base of the wound (Plate 3.38-8). 5) All tree limbs damaged during construction or removed for any other reason shall be cut off above the collar at the preceding branch junction (Plate 3.38-8). 6) Care for serious injuries shall be prescribed by a forester or a tree specialist. c. Fertilization: Broadleaf trees that have been stressed or damaged shall receive a heavy application of fertilizer to aid their recovery. 1) Trees shall be fertilized in the late fall (after October 1) or the early spring (from the time frost is out of the ground until May 1). Fall applications are preferred, as the nutrients will be made available over a longer period of time. 2) Fertilizer shall be applied to the soil over the feeder roots (see Plate 3.38-9). In no case should it be applied closer than 3 feet to the trunk. The root system of conifers extends some distance beyond the drip line. Increase the area to be fertilized by one fourth the area of the crown. 3) Fertilizer shall be applied using approved fertilization methods and equipment. III - 411 1992 3.38 TREE CARE I 1 11 1 , I I yl I , 1I1I `L: I _r i 1 1l i = I 1 I,I I ` + l{'i Nil iuh lii ail ill.& ,I IL TREE WOUND TRIM AND TAPER TREATING BARK WOUNDS 111 i; 2 \\\ 2 i'�/ 1 ' 111111?? , N., 31 I ! 3 / ti ' / !' 1 ► it I ,, :, 1 �t 4.:.-9",1 : I1I ,, :. l 1 : I I 1 I i'l y TREE COLLAR I li I 1 I 1' I, + i f II 1l1� I : II11II� 1I1I� i �I��IYI I I' � i INCORRECT CORRECT CORRECT PRUNING DAMAGED BRANCHES Source: Public Facilities Manual, Vol. III, Fairfax Co., Va., 1976. Plate 3.38-8 4) Formulations and application rates shall conform to the guidelines given in Table 3.38-A. Maintain a ground cover of organic mulch around trees that is adequate to prevent erosion, protect roots, and hold water. III - 412 1992 3.38 TREE FERTILIZATION illfir 4141*-,:da, 41 :0, lirs,-,..4.100.1-- .4*....31i me......__________ *oil, art lk 41141.1 solle IbAlamit "W II ir IIIIP irk- 1411/4..... DO NOT FEED AREA ADJACENT DRIP LINE I TO TRUNK (APPROX. 1/3 OF �I DIAMETER OF TOTAL ROOT AREA) SINCE FEW FEEDER AM ARE IN THIS AREA. 111140. _-o c o .6. Arc c c o O ,{ \•••\o\ (/� IRw.O O O p Liar"- ` -- Ir. to'\O O d O O R�Ir. O Q O 1 OAia.\ O O JIL — MU. o 0 0 .. � \ \-O _ \ O - -_ AAL \- _ O -�� M. .MAW M. ilik EXTEND FEEDING CIRCLE SIGHTLY BEYOND THE DRIP LINE OF THE TREE I I — II-1I III—I11- . _I-III -I�I—I IIIIIIII IIII�IIIII I HOLES SHOULD BE APPROXIMATELY 18" DEEP AND 2' APART, AND THEY SHOULD SLANT TOWARD THE TRUNK. Source: Tree Maintenance, Pirone, 1979. Plate 3.38-9 III - 413 1992 3.07 STD & SPEC 3.07 STORM DRAIN o INLET PROTECTION IP Definition A sediment filter or an excavated impounding area around a storm drain drop inlet or curb inlet. Purpose To prevent sediment from entering storm drainage systems prior to permanent stabilization of the disturbed area. Conditions Where Practice Applies Where storm drain inlets are to be made operational before permanent stabilization of the corresponding disturbed drainage area. Different types of structures are applicable to different conditions (see Plates 3.07-1 through 3.07-8). a . 'tea« "ti.li 'a ° • yW.� .- `-`r.. ». : '`,, ' a.y .= `'•",� "7'. 3.s :1�' ' :i, ,. a. a f ¢ '.y'x =.✓.tom*" . P ar 6 pv '"' �Y �Ma ^� �be�y ' 2 .yr.; , ,<' v'e &«a`g 3ik .�',!°c.�owa. 'ub �u �, "n.v� ' .r, , ``'t •:i r e `<,d is ,,"..it 'S,O+;'4',',4 '7- ••'' lb ^*- t.'''''4" '* -• . O. s*. -*„;.,,,C.,p>,,,'74''f;-..,,,7=7;'::',,,^: ,,:%;,,,,;,,,‘,,„ ,;• '‘,„,,,,,,...,•:;-,,' ,.• ea.,<-7--4., ,.,/,<,-;--;'''''.--,'"-' .- ' ..-``'6t'4°, .,,,i‘'‘'',It':"...,:e h:''''iv.':4,4•"'": 4:-. dnw ey=r , §. 4' 4. i R ,,,,,,.., yy . � "`��fh Y.eY*w. }.S� «..� jr; �$` 4 tr,. ..„,„,,,,, -,, : ,,,,..„ „, ` 8 �° i., .vN. "fir. . ,,,,,i: q�, III - 31 1992 3.07 Planning Considerations Storm sewers which are made operational prior to stabilization of the associated drainage areas can convey large amounts of sediment to natural drainageways. In case of extreme sediment loading, the storm sewer itself may clog and lose a major portion of its capacity. To avoid these problems, it is necessary to prevent sediment from entering the system at the inlets. This practice contains several types of inlet filters and traps which have different applications dependent upon site conditions and type of inlet. Other innovative techniques for accomplishing the same purpose are encouraged,but only after specific plans and details are submitted to and approved by the appropriate Plan-Approving Authority. Care should be taken when choosing a specific type of inlet protection. Field experience has shown that inlet protection which causes excessive ponding in an area of high construction activity may become so inconvenient that it is removed or bypassed, thus transmitting sediment-laden flows unchecked. In such situations, a structure with an adequate overflow mechanism should be utilized. The following inlet protection devices are for drainage areas of one acre or less. Runoff from larger disturbed areas should be routed to a TEMPORARY SEDIMENT TRAP (Std. & Spec. 3.13) or a TEMPORARY SEDIMENT BASIN (Std. & Spec. 3.14). The best way to prevent sediment from entering the storm sewer system is to stabilize the site as quickly as possible, preventing erosion and stopping sediment at its source. Stone is utilized as the chief ponding/filtering agent in most of the inlet protection types described in this specification. The various types of"coarse aggregates"which are depicted are able to filter out sediment mainly through slowing down flows directed to the inlet by creating an increased flow path for the stormwater (through void space in the respective stone). The stone filtering medium by no means slows stormwater flowrate as does filter cloth and therefore cannot provide the same degree of filter efficiency when smaller silt and clay particles are introduced into stormwater flows. However, as mentioned earlier, excessive ponding in busy areas adjacent to stormwater inlets is in many cases unacceptable - that is why stone must be utilized with many installations. Fortunately,in most instances, inlet protection utilizing stone should not be the sole control measure. At the time that storm sewer inlet and associated appurtances become operational, areas adjacent to the structures are most likely at final grade or will not be altered for extended periods;this is the time when TEMPORARY SEEDING (Std.&Spec. 3.31) and other appropriate controls should be implemented to enhance sediment-loss mitigation. In addition, by varying stone sizes used in the construction of inlet protection, a greater degree of sediment removal can be obtained. As an option, filter cloth can be used with the stone in these devices to further enhance sediment removal. Notably, the potential inconvenience of excessive ponding must be examined with these choices, especially the latter. HI - 32 1992 3.07 Design Criteria 1. The drainage area shall be no greater than 1 acre. 2. The inlet protection device shall be constructed in a manner that will facilitate clean- out and disposal of trapped sediment and minimize interference with construction activities. 3. The inlet protection devices shall be constructed in such a manner that any resultant ponding of stormwater will not cause excessive inconvenience or damage to adjacent areas or structures. 4. Design criteria more specific to each particular inlet protection device will be found on Plates 3.07-1 through 3.07-8. 5. For the inlet protection devices which utilize stone as the chief ponding/filtering medium, a range of stone sizes is offered; VDOT#3, #357, or #5 Coarse Aggregate should be used. The designer/plan reviewer should attempt to get the greatest amount of filtering action possible (by using smaller-sized stone), while not creating significant ponding problems. 6. In all designs which utilize stone with a wire-mesh support as a filtering mechanism, the stone can be completely wrapped with the wire mesh to improve stability and provide easier cleaning. 7. Filter Fabric may be added to any of the devices which utilize "coarse aggregate" stone to significantly enhance sediment removal. The fabric, which must meet the physical requirements noted for "extra strength" found in Table 3.05-B, should be secured between the stone and the inlet (on wire-mesh if it is present). As a result of the significant increase in filter efficiency provided by the fabric, a larger range of stone sizes (VDOT #1, #2 or #3 Coarse Aggregate) may be utilized with such a configuration. The larger stone will help keep larger sediment masses from clogging the cloth. Notably, significant ponding may occur at the inlet if filter cloth is utilized in this manner. Construction Specifications 1. Silt Fence Drop Inlet Protection • a. Silt Fence shall conform to the construction specifications for"extra strength" found in Table 3.05-B and shall be cut from a continuous roll to avoid joints. b. For stakes, use 2 x 4-inch wood (preferred) or equivalent metal with a minimum length of 3 feet. III - 33 1992 3.07 c. Space stakes evenly around the perimeter of the inlet a maximum of 3-feet apart, and securely drive them into the ground, approximately 18-inches deep (see Plate 3.07-1). d. To provide needed stability to the installation, frame with 2 x 4-inch wood strips around the crest of the overflow area at a maximum of 1 Z feet above the drop inlet crest. e. Place the bottom 12 inches of the fabric in a trench (see Plate 3.07-1) and backfill the trench with 12 inches of compacted soil. f. Fasten fabric securely by staples or wire to the stakes and frame. Joints must be overlapped to the next stake. g. It may be necessary to build a temporary dike on the downslope side of the structure to prevent bypass flow. 2. Gravel and Wire Mesh Drop Inlet Sediment Filter a. Wire mesh shall be laid over the drop inlet so that the wire extends a minimum of 1 foot beyond each side of the inlet structure. Wire mesh with 1/2-inch openings shall be used. If more than one strip of mesh is necessary, the strips shall be overlapped. b. Coarse aggregate shall be placed over the wire mesh as indicated on Plate 3.07-2. The depth of stone shall be at least 12 inches over the entire inlet opening. The stone shall extend beyond the inlet opening at least 18 inches on all sides. c. If the stone filter becomes clogged with sediment so that it no longer adequately performs its function, the stones must be pulled away from the inlet, cleaned and/or replaced. Note: This filtering device has no overflow mechanism; therefore, ponding is likely especially if sediment is not removed regularly. This type of device must never be used where overflow may endanger an exposed fill slope. Consideration should also be given to the possible effects of ponding on traffic movement, nearby structures, working areas, adjacent property, etc. 3. Block and Gravel Drop Inlet Sediment Filter a. Place concrete blocks lengthwise on their sides in a single row around the perimeter of the inlet, with the ends of adjacent blocks abutting. The height of the barrier can be varied, depending on design needs, by stacking combinations of 4-inch, 8-inch and 12-inch wide blocks. The barrier of blocks shall be at least 12-inches high and no greater than 24-inches high. III - 34 1992 3.07 SILT FENCE DROP INLET PROTECTION 2 X 4' WOOD FRAME DROP INLET WITH GRATE ..... 1 _`�``. FRAME 1.5' MAX. \ 0-0 :.14111111--, 3' MIN. II II , : 4 .. GATHER I' I I I �� ATCCORNERS IJ PERSPECTIVE VIEWS STAKE FABRIC- U I II _ I. �� ;,;11. 111 /� ,,1 1 1 I% TIN . alilll ; ii ELEVATION OF STAKE AND FABRIC ORIENTATION DETAIL A SPECIFIC APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE WHERE THE INLET DRAINS A RELATIVELY FLAT AREA (SLOPE NO GREATER THAN 5%) WHERE THE INLET SHEET OR OVERLAND FLOWS (NOT EXCEEDING 1 C.F.S.) ARE TYPICAL., THE METHOD SHALL NOT APPLY TO INLETS RECEIVING CONCENTRATED FLOWS, SUCH AS IN STREET OR HIGHWAY MEDIANS. Source: N.C. Erosion and Sediment Control Planning and Design Manual, 1988 Plate 3.07-1 III - 35 1992 3.07 GRAVEL AND WIRE MESH DROP INLET SEDIMENT FILTER L 18" MIN. GRAVEL*(1 2"MIN. DEPTH) Nicisilm7qut RUNOFF WATER 1���. `7res`.'iCri'11W4:'/0%4./`r�k WITH SEDIMENT re-=liam% �����mrr+•�� �,ir� 4*�i11 . ice.i �•. • �4 . -st►�is1:r�"'�•tileat -1Mt,1�f,Iy�!�a' aria 11 .1III I _►I nv a SEDIMENT -e. WIRE MESH FILTERED WATER • SPECIFIC APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE WHERE HEAVY CONCENTRATED FLOWS ARE EXPECTED , BUT NOT WHERE PONDING AROUND THE STRUCTURE MIGHT CAUSE EXCESSIVE INCONVENIENCE OR DAMAGE TO ADJACENT STRUCTURES AND UNPROTECTED AREAS. * GRAVEL SHALL BE VD'OT #3, #357 OR #5 COARSE AGGREGATE. Source: Va. DSWC Plate 3.07-2 III - 36 1992 3.07 b. Wire mesh shall be placed over the outside vertical face (webbing) of the concrete blocks to prevent stone from being washed through the holes in the blocks. Wire mesh with 1/2-inch openings shall be used. c. Stone shall be piled against the wire to the top of the block barrier, as shown in Plate 3.07-3. d. If the stone filter becomes clogged with sediment so that it no longer adequately performs its function, the stone must be pulled away from the blocks, cleaned and replaced. 4. Excavated Drop Inlet Sediment Trap a. The excavated trap shall be sized to provide a minimum storage capacity calculated at the rate of 134 cubic yards per acre of drainage area. A trap shall be no less than 1-foot nor more than 2-feet deep measured from the top of the inlet structure. Side slopes shall not be steeper than 2:1 (see Plate 3.07-4). b. The slope of the basin may vary to fit the drainage area and terrain. Observations must be made to check trap efficiency and modifications shall be made as necessary to ensure satisfactory trapping of sediment. Where an inlet is located so as to receive concentrated flows, such as in a highway median, it is recommended that the basin have a rectangular shape in a 2:1 (length/width) ratio, with the length oriented in the direction of the flow. c. Sediment shall be removed and the trap restored to its original dimensions when the sediment has accumulated to one-half the design depth of the trap. Removed sediment shall be deposited in a suitable area and in a manner such that it will not erode. 5. Sod Drop Inlet Sediment Filter a. Soil shall be prepared and sod installed according to the specifications in Std. & Spec. 3.33, SODDING. b. Sod shall be placed to form a turf mat covering the soil for a distance of 4 feet from each side of the inlet structure, as depicted in Plate 3.07-5. 6. Gravel Curb Inlet Sediment Filter a. Wire mesh with 1/2-inch openings shall be placed over the curb inlet opening so that at least 12 inches of wire extends across the inlet cover and at least 12 inches of wire extends across the concrete gutter from the inlet opening, as depicted in Plate 3.07-6. III - 37 1992 3.07 BLOCK AND GRAVEL DROP INLET SEDIMENT FILTER • WIRE SCREEN \ / CONCRETE BLOCK 4,111 ?am. may,/�I11 ❑❑11V ��Ilye`!��� �r.41��: Attell11111111111111111111;t144 .11 4, 411-00j t11 40 ,l +.t414.%".I 4 gistrolfamwefiratifeenislIV - * p-ieei1�t-���i� t,4�lol��o�� GRAVEL* FILTER WIRE SCREEN i FILTERED WATER OVERFLOO . - RUNOFF WATER 44.11 WITH SEDIMENT i�a'i 00 = ail - r �=l Q DROP INLET p' WITH GRATE SEDIMENT ill SPECIFIC APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE WHERE HEAVY FLOWS ARE EXPECTED AND WHERE AN OVERFLOW CAPACITY IS NECESSARY TO PREVENT EXCESSIVE PONDING AROUND THE STRUCTURE. * GRAVEL SHALL BE VDOT #3, #357 OR #5 COARSE AGGREGATE. Source: Va. DSWC Plate 3.07-3 - HI - 38 1992 3.07 EXCAVATED DROP INLET SEDIMENT TRAP FLOW \� �`\ 'li� � FLOW rf \ FLOW_.7 r (C- \ \~ FLOW SEDIMENT-LADEN RUNOFF t �, DEPTH BELOW TOP OF INLET: • • REQUIRED MIN. 1'— MAX. 2' - - ' • • •:u=11=11' • •• • • • •••417I • .11 C=C=C= — I ' ,I � • LJ J I.11=11=1K • y : �. �• - • 11-II: - . 4" II : • I • mI Ii iI i 11=11. 11=n . mil- IL=C MAX. OPE z 11=11=111-1=471.-11.' 11.-1-1�-11. 11-1L-1- =11 IL•==11.11m 1=11.=1 11=1 —'=11-=11= 1.=�1 = -11.=11. 11=11: If.=.11l 4 . •q11=11. STORM WATER WITH ,111! WEEP • 11=11.11 LARGER PARTICLES LARGER PARTICLES =1 II HOLES •.I = SETTLE OUT • REMOVED 11. • FOR • IL; : Ill•1 : DEWATERING I.II.I • . lial DRAIN INLET -�11=°• a I1.1 II---II— n #= =:11.=I:= 4.=II=11:=.I: =II=IW SPECIFIC APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE WHERE HEAVY FLOWS ARE EXPECTED AND WHERE AN OVERFLOW CAPABILITY AND EASE OF MAINTENANCE ARE DESIRABLE. Source: Michigan Soil Erosion and Sediment Control Guidebook, 1975, and USDA-SCS Plate 3.07-4 III - 39 1992 3.07 SOD DROP INLET SEDIMENT FILTER iimmitom 1- iii=matmenua — r- -~ 4' 4' FOUR 1-FOOT WIDE STRIPS OF SOD ON EACH SIDE OF THE DROP INLET RUNOFF SEDIMENT WATER FILTERED WATER WITH 1.�11=11=:11=11=116=11.=11:�11:=1111=11.11.=11.=11: •1-11.-11. 11-11=11=11-11=11=11-11. —11.=11.=11.=11=11=11. ' . 4. 1.=11=11-11.=11 • • -II=.11=11:LIE . •. , . • SPECIFIC APLLICATION THIS METHOD OF INLET PROTECTION IS APPPLICABLE ONLY AT THE TIME OF PERMANENT SEEDING, TO PROTECT THE INLET FROM SEDIMENT AND MULCH MATERIAL UNTIL PERMANENT VEGETATION HAS BECOME ESTABLISHED. Source: Va. DSWC Plate 3.07-5 III - 40 . 1992 3.07 GRAVEL CURB INLET SEDIMENT FILTER GRAVEL FILTER 12" RUNOFF WATER ��� )�ea' WIRE MESH �{`; a'_•�!.� FILTERED WATER Ik -711 ,,,�,, I II ,'III 111E1 • - r� _ - SEDIMENT /1111— II IIII I= e•• Iu►II CONCRETE GUTTER 12" CURB INLET SPECIFIC APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE AT CURB INLETS WHERE PONDING IN FRONT OF THE STRUCTURE IS NOT LIKELY TO CAUSE INCONVENIENCE OR DAMAGE TO ADJACENT STRUCTURES AND UNPROTECTED AREAS. * GRAVEL SHALL BE VDOT #3, #357 OR 5 COARSE AGGREGATE. • Source: Va. DSWC Plate 3.07-6 III - 41 1992 3.07 b. Stone shall be piled against the wire so as to anchor it against the gutter and inlet cover and to cover the inlet opening completely. c. If the stone filter becomes clogged with sediment so that it no longer adequately performs its function, the stone must be pulled away from the block, cleaned and replaced. 7. Curb Inlet Protection with 2-inch x 4-inch Wooden Weir a. Attach a continuous piece of wire mesh(30-inch minimum width x inlet throat length plus 4 feet) to the 2-inch x 4-inch wooden weir (with a total length of throat length plus 2 feet) as shown in Plate 3.07-7. Wood should be "construction grade" lumber. b. Place a piece of approved "extra-strength" filter cloth of the same dimensions as the wire mesh over the wire mesh and securely attach to the 2-inch x 4-inch weir. c. Securely nail the 2-inch x 4-inch weir to the 9-inch long vertical spacers which are to be located between the weir and inlet face at a maximum 6-foot spacing. d. Place the assembly against the inlet throat and nail 2-foot (minimum) lengths of 2-inch x 4-inch board to the top of the weir at spacer locations. These 2- inch x 4-inch anchors shall extend across the inlet tops and be held in place by sandbags or alternate weight. e. The assembly shall be placed so that the end spacers are a minimum 1 foot beyond both ends of the throat opening. f. Form the wire mesh and filter cloth to the concrete gutter and against the face of curb on both sides of the inlet. Place coarse aggregate over the wire mesh and filter fabric in such a manner as to prevent water from entering the inlet under or around the filter cloth. g. This type of protection must be inspected frequently and the filter cloth and stone replaced when clogged with sediment. h. Assure that storm flow does not bypass inlet by installing temporary earth or asphalt dikes directing flow into inlet. 8. Block and Gravel Curb Inlet Sediment Filter a. Two concrete blocks shall be placed on their sides abutting the curb at either side of the inlet opening. III - 42 1992 3.07 CURE INLET PROTECTION WITH 2 -INCH X 4 -INCH WOODEN WEIR GRAVEL* 6' MAXIMUM SPACING OF 2" X4" SPACERS 41*----..4 .04• 2" X 4" ANCHORS EMERGENCY OVERFLOW rizt4kttz. Awl ...4mitk, ..),....... 41a14„ cfaatimeve,, istosimpio. . . .........0,000.4 4 ;%��`�%�/�'• "'"�� / PERSPECTIVE VIEW 2" X 4 WEIR • % 2" X 4" SPACER SAND BAG OR 2' MINIMUM LENGTH ALTERNATE WEIGHT OF 2" X 4" 2" X 4 WEIR GRAVEL «j SIDE ELEVATION ��{ • . / i ~ �i 2" X 4" SPACER fel WIRE MESH - •• ::.%;:: INLET- SPECIFIC APPLICATION -II p_'• >�. ','. TO ' PIPE THIS METHOD OF INLET PROTECTION IS APPLICABLE TO CURB INLETS WHERE A STURDY, COMPACT INSTALLATION �i IS DESIRED. EMERGENCY OVERFLOW CAPABILITIES ARE T MINIMAL, SO EXPECT SIGNIFICANT PONDING WITH THIS T MEASURE. GRAVEL SHALL BE VDOT COARSE AGGREGATE #3, #357 OR #5 Source: 1983 Maryland Standards and Specifications for Soil Erosion and Sediment Control, and USDA-SCS Plate 3.07-7 III - 43 1992 3.07 b. A 2-inch x 4-inch stud shall be cut and placed through the outer holes of each spacer block to help keep the front blocks in place. c. Concrete blocks shall be placed on their sides across the front of the inlet and abutting the spacer blocks as depicted in Plate 3.07-8. d. Wire mesh shall be placed over the outside vertical face (webbing) of the concrete blocks to prevent stone from being washed through the holes in the blocks. Wire mesh with 1/2-inch openings shall be used. e. Coarse aggregate shall be piled against the wire to the top of the barrier as shown in Plate 3.07-8. f. If the stone filter becomes clogged with sediment so that it no longer adequately performs its function, the stone must be pulled away from the blocks, cleaned and/or replaced. Maintenance 1. The structure shall be inspected after each rain and repairs made as needed. 2. Sediment shall be removed and the trap restored to its original dimensions when the sediment has accumulated to one half the design depth of the trap. Removed sediment shall be deposited in a suitable area and in such a manner that it will not erode. 3. Structures shall be removed and the area stabilized when the remaining drainage area has been properly stabilized. • III - 44 1992 3.07 BLOCK k GRAVEL CURB INLET SEDIMENT FILTER CURB INLET -------- - O - alltak .11.114 .A*0141.— Wit,fir+atilei .b., xmas vest d i�►.r test it WIRE SCREEN l� CONCRETE BLOCK '� GRAVEL FILTER RUNOFF OVERFLOW WATER WITH FILTERED WATER SEDIMENT �� �i+ialir_ _ =kaII� III= aililliiii I■� I MIIIU um o I 1I1. SEDIMENT I II I `---MITI WIRE SCREEN - . \ 4, 117 2" X 4" WOOD STUD CURB INLET SPECIAL APPLICATION THIS METHOD OF INLET PROTECTION IS APPLICABLE AT CURB INLETS WHERE AN OVERFLOW CAPABILITY IS NECESSARY TO PREVENT EXCESSIVE PONDING IN FRONT OF THE STRUCTURE. * GRAVEL SHALL BE VDOT #3, #357 OR #5 COARSE AGGREGATE Source: Va. DSWC Plate 3.07-8 III - 45 1992 3.30 STD & SPEC 3.30 m TOPSOILING TO Definition Methods of preserving and using the surface layer of undisturbed soil, often enriched in organic matter, in order to obtain a more desirable planting and growth medium. Purpose To provide a suitable growth medium for final site stabilization with vegetation. Conditions Where Practice Applies 1. Where the preservation or importation of topsoil is determined to be the most effective method of providing a suitable growth medium. . -, - - „"' °,:` ,°),: e,,=✓w4*. ,-';xe as { ' -'•-', .. i ,",' 6i; "': W 4'-';6Y:jam `,' : M �a to N� tea a'a i.u".."..' % _y V. i , �eo,az `..,r, i.-=,. ,.,,-....+..A... !„.. . ..., am'^ 4` .r r,„�i+ „ .,af l ate„ -'ti.. .-...• •.. III - 279 1992 3.30 2. Where the subsoil or existing soil presents the following problems: a. The texture, pH, or nutrient balance of the available soil cannot be modified by reasonable means to provide an adequate growth medium. b. The soil material is too shallow to provide an adequate root zone and to supply necessary moisture and nutrients for plant growth. c. The soil contains substances potentially toxic to plant growth. 3. Where high-quality turf is desirable to withstand intense use or meet aesthetic requirements. 4. Where ornamental plants will be established. 5. Only on slopes that are 2:1 or flatter unless other measures are taken to prevent erosion and sloughing. Planning Considerations Topsoil is the surface layer of the soil profile, generally characterized as being darker than the subsoil due to the presence of organic matter. It is the major zone of root development, carrying much of the nutrients available to plants, and supplying a large share of the water used by plants. Although topsoil provides an excellent growth medium, there are disadvantages to its use. Stripping, stockpiling, and reapplying topsoil, or importing topsoil, may not always be cost- effective. Topsoiling can delay seeding or sodding operations, increasing the exposure time of denuded areas. Most topsoil contains weed seeds,and weeds may compete with desirable species. Advantages of topsoil include its high organic matter content and friable consistence,water- holding capacity, and nutrient content. In site planning, the option of topsoiling should be compared with that of preparing a seedbed in subsoil. The clay content of subsoils does provide high moisture availability and deter leaching of nutrients and, when properly limed and fertilized, subsoils may provide a good growth medium which is generally free of weed seeds. In many cases topsoiling may not be required for the establishment of less demanding, lower maintenance plant material. Topsoiling is strongly recommended where ornamental plants or high-maintenance turf will be grown. Topsoiling is a required procedure when establishing vegetation on shallow soils, soils containing potentially toxic materials, and soils of critically low pH (high acid) levels. If topsoiling is to be done, the following items should be considered: t III - 280 1992 3.30 1. Whether an adequate volume of topsoil exists on the site. Topsoil will be spread at a compacted depth of 2 to 4 inches (depths closer to 4 inches are preferred). 2. Location of the topsoil stockpile so that it meets specifications and does not interfere with work on the site. 3. Allow sufficient time in scheduling for topsoil to be spread and bonded prior to seeding, sodding, or planting. 4. Care must be taken not to apply topsoil to subsoil if the two soils have contrasting textures. Clayey topsoil over sandy subsoil is a particularly poor combination, as water may creep along the junction between the soil layers, causing the topsoil to slough. Sandy topsoil over a clay subsoil is equally as likely to fail. 5. If topsoil and subsoil are not properly bonded,water will not infiltrate the soil profile evenly and it will be difficult to establish vegetation. Topsoiling of steep slopes should be discouraged unless good bonding of soils can be achieved. Specifications Materials Field exploration of the site shall be made to determine if there is sufficient surface soil of good quality to justify stripping. Topsoil shall be friable and loamy (loam, sandy loam, silt loam, sandy clay loam, clay loam). It shall be free of debris, trash, stumps, rocks, roots, and noxious weeds, and shall give evidence of being able to support healthy vegetation. It shall contain no substance that is potentially toxic to plant growth. All topsoil shall be tested by a recognized laboratory for the following criteria: Organic matter content shall be not less than 1.5% by weight. pH range shall be from 6.0-7.5. If pH is less than 6.0, lime shall be added in accordance with soil test results or in accordance with the recommendations of the vegetative establishment practice being used. Soluble salts shall not exceed 500 ppm. If additional off-site topsoil is needed, it must meet the standards stated above. Stripping Topsoil operations should not be performed when the soil is wet or frozen. Stripping shall be confined to the immediate construction area. A 4-to 6-inch stripping depth is common, III - 281 1992 3.30 but depth may vary depending on the particular soil. All perimeter dikes,basins, and other sediment controls shall be in place prior to stripping. Stockpiling Topsoil shall be stockpiled in such a manner that natural drainage is not obstructed and no off-site sediment damage shall result. Stabilize or protect stockpiles in accordance with MS #2. Side slopes of the stockpile shall not exceed 2:1. Perimeter controls must be placed around the stockpile immediately; seeding of stockpiles shall be completed within 7 days of the formation of the stockpile, in accordance with Std. & Spec. 3.31, TEMPORARY SEEDING if it is to remain dormant for longer than 30 days (refer to MS #1 and MS #2). Site Preparation Prior to and Maintenance During Topsoiling Before topsoiling, establish needed erosion and sediment control practices such as diversions, grade stabilization structures,berms,dikes, level spreaders,waterways,sediment basins, etc. These practices must be maintained during topsoiling. • Grading: Previously established grades on the areas to be topsoiled shall be maintained according to the approved plan. Liming: Where the pH of the subsoil is 6.0 or less, or the soil is composed of heavy clays, agricultural limestone shall be spread in accordance with the soil test or the vegetative establishment practice being used. Bonding: After the areas to be topsoiled have been brought to grade, and immediately prior to dumping and spreading the topsoil, the subgrade shall be loosened by discing or scarifying to a depth of at least 2 inches to ensure bonding of the topsoil and subsoil. Applying Topsoil Topsoil shall not be placed while in a frozen or muddy condition, when topsoil or subgrade is excessively wet, or in a condition that may otherwise be detrimental to proper grading or proposed sodding or seeding. The topsoil shall be uniformly distributed to a minimum compacted depth of 2 inches on 3:1 or steeper slopes and 4 inches on flatter slopes. (See Table 3.30-A to determine volume of topsoil required for application to various depths). Any irregularities in the surface, resulting from topsoiling or other operations, shall be corrected in order to prevent the formation of depressions or water pockets. It is necessary to compact the topsoil enough to ensure good contact with the underlying soil • and to obtain a level seedbed for the establishment of high maintenance turf. However, undue compaction is to be avoided as it increases runoff velocity and volume, and deters • III - 282 1992 3.30 seed germination. Special consideration should be given to the types of equipment used to place topsoil in areas to receive fine turf. Avoid unnecessary compaction by heavy machinery whenever possible. In areas which are not going to be mowed, the surface should be left rough in accordance with SURFACE ROUGHENING (Std. & Spec. 3.29). Soil Sterilants No sod or seed shall be placed on soil which has been treated with soil sterilants until sufficient time has elapsed to permit dissipation of toxic materials. TABLE 3.30-A CUBIC YARDS OF TOPSOIL REQUIRED FOR APPLICATION TO VARIOUS DEPTHS Depth Per 1,000 (inches) Square Feet Per Acre 1 3.1 134 2 6.2 268 3 9.3 403 4 12.4 537 5 15.5 672 6 18.6 806 Source: Va. DSWC • III - 283 1992 3.35 STD & SPEC 3.35 MULCHING411 Definition Application of plant residues or other suitable materials to the soil surface. Purposes 1. To prevent erosion by protecting the soil surface from raindrop impact and reducing the velocity of overland flow. 2. To foster the growth of vegetation by increasing available moisture and providing insulation against extreme heat and cold. Conditions Where Practice Applies 1. Areas which have been permanently seeded (see Std. & Spec. 3.32, PERMANENT SEEDING) should be mulched immediately following seeding. v wa 1 .r..:w„^, K ••� S�' i :%4 Y."J- .✓, ., A J� TR bfF ., fi.: <Qiy v� .....Y*'..21/4t, • „"cZx._Y\ ,^ ,f III - 349 1992 3.35 2. Areas which cannot be seeded because of the season should be mulched to provide some protection to the soil surface. An organic mulch should be used, and the area then seeded as soon weather or seasonal conditions permit. It is not recommended that fiber mulch be used alone for this practice; at normal application rates it just simply does not provide the protection that is achieved using other types of mulch. 3. Mulch may be used together with plantings of trees, shrubs, or certain ground covers which do not provide adequate soil stabilization by themselves. 4. Mulch shall be used in conjunction with temporary seeding operations as specified in TEMPORARY SEEDING, Std. & Spec. 3.31. Planning Considerations Mulches are applied to the soil surface to conserve a desirable soil property or to promote plant growth. A surface mulch is one of the most effective means of controlling runoff and erosion on disturbed land. Mulches can increase the infiltration rate of the soil, reduce soil moisture loss by evaporation, prevent crusting and sealing of the soil surface, modify soil temperatures, and provide a suitable microclimate for seed germination. Organic mulch materials, such as straw,wood chips, bark, and fiber mulch have been found to be the most effective. Chemical soil stabilizers or soil binders should not be used alone for mulch. These materials are useful to bind organic mulches together to prevent displacement. Avariety of manufactured SOIL STABILIZATION BLANKETS AND MATTING(see Std. & Spec. 3.36) have been developed for erosion control in recent years. Some of these products can be used as mulches,particularly in critical areas such as waterways. They also may be used to hold other mulches to the soil surface. The choice of materials for mulching will be based on the type of soil to be protected, site conditions, season and economics. It is especially important to mulch liberally in mid- summer and prior to winter, and on cut slopes and southern slope exposures. Organic Mulches Straw - The mulch most commonly used in conjunction with seeding. The straw should come from wheat or oats (free of troublesome weed seeds) and may be spread by hand or machine. Straw can be windblown and must be anchored down by an acceptable method. III - 350 1992 3.35 Hay - May be used in lieu of straw where volunteers will not present a problem, and may be spread by hand or machine. Hay can be windblown and must also be anchored or tacked down. Corn Stalks - These should be shredded into 4- to 6-inch lengths. Stalks decompose slowly and are resistant to displacement. Wood Chips - Suitable for areas that will not be closely mowed, and around ornamental plantings. Chips decompose slowly and do not require tacking. They must be treated with 12 pounds of nitrogen per ton to prevent nutrient deficiency in plants; however, can be a very inexpensive mulch if chips are obtained from trees cleared on the site. Bark Chips. Shredded Bark- These are by-products of timber processing which are used in landscaped plantings. Bark is also a suitable mulch for areas planted to grasses and not closely mowed. It may be applied by hand or mechanically and is not usually toxic to grasses or legumes; additional nitrogen fertilizer is not required. Fiber Mulch - Used in hydroseeding operations and applied as part of the slurry. It creates the best seed-soil contact when applied over top of(as a separate operation) newly seeded areas. These fibers do not require tacking, although tacking agents or binders are sometimes used in conjunction with the application of fiber mulch. This form of mulch does not provide sufficient protection to highly erodible soils. Additionally, fiber mulch will not be considered adequate mulch when used during the dry summer months or when used for late fall mulch cover. Use straw mulch during these periods. Fiber mulch may be used to tack (anchor) straw mulch. This treatment is well suited for steep slopes, critical areas, and areas susceptible to displacement. There are other organic materials which make excellent mulches but are only available locally or seasonally. Creative use of these materials can reduce costs. Chemical Mulches and Soil Binders A wide range of synthetic, spray-on materials are marketed to stabilize and protect the soil surface. These are emulsions or dispersions of vinyl compounds, rubber or other substances which are mixed with water and applied to the soil. They may be used alone in some cases as temporary stabilizers, or in conjunction with fiber mulches or straw. When used alone, chemical mulches do not have the capability to insulate the soil or retain soil moisture that organic mulches have. This soil protection is also easily damaged by traffic. Application of these mulches is usually more expensive than organic mulching, and the mulches decompose in 60-90 days. Blankets and Matting Field experience has shown that plastic netting, when used alone, does not retain soil moisture or modify soil temperature. In some cases it may stabilize the soil surface while III - 351 1992 3.35 grasses are being established, but is primarily used in grassed waterways and on slopes to hold straw or similar mulch in place. Jute mesh and other soil stabilization blankets are good choices for mulching on difficult slopes and in minor drainage swales. Most of the soil stabilization mattings (used to create a permanent matrix for root growth within the soil) must receive mulching in order to properly stabilize an area. Notably,some manufacturers have recently developed permanent mattings which include self-contained, temporary mulching materials; however, these measures will have to meet the requirements noted in Std. & Spec. 3.36, SOIL STABILIZATION BLANKETS AND MATTING,before they can be recommended for use on steep slopes and in channel flow situations. The most critical aspect of installing blankets and mats is obtaining firm, continuous contact between the material and the soil. Without such contact, the material may fail and thereby allow erosion to occur. It is important to use an adequate number of staples and make sure the material is installed properly in order to maximize soil protection. These products are discussed in more detail in Std. & Spec. 3.36, SOIL STABILIZATION BLANKETS & MATTING. Specifications Organic.Mulches Organic mulches may be used in any area where mulch is required, subject to the restrictions noted in Table 3.35-A. Materials: Select mulch material based on site requirements, availability of materials, and availability of labor and equipment. Table 3.35-A lists the most commonly used organic mulches. Other materials, such as peanut hulls and cotton burs, may be used with the permission of the local Plan-Approving Authority. Prior to mulching: Complete the required grading and install needed sediment control practices. Lime and fertilizer should be incorporated and surface roughening accomplished as needed. Seed should be applied prior to mulching except in the following cases: a. Where seed is to be applied as part of a hydroseeder slurry containing fiber mulch. b. Where seed is to be applied following a straw mulch spread during winter months. • III - 352 1992 3.35 TABLE 3.35-A ORGANIC MULCH MATERIALS AND APPLICATION RATES RATES: MULCHES: NOTES: Per Acre Per 1000 sq. ft. Straw or Hay 1 Z - 2 tons 70 - 90 lbs. Free from weeds and coarse (Minimum 2 matter. Must be anchored. tons for Spread with mulch blower winter cover) or by hand. Fiber Mulch Minimum 35 lbs. Do not use as mulch for 1500 lbs. winter cover or during hot, dry periods.* Apply as slurry. Corn Stalks 4 - 6 tons 185 - 275 lbs. Cut or shredded in 4-6" lengths. Air-dried. Do not use in fine turf areas. Apply with mulch blower or by hand. Wood Chips 4 - 6 tons 185 - 275 lbs. Free of coarse matter. Air- dried. Treat with 12 lbs nitrogen per ton. Do not use in fine turf areas. Apply with mulch blower, chip handler, or by hand. Bark Chips 50 - 70 cu. 1-2 cu. yds. Free of coarse matter. Air- or yds. dried. Do not use in fine Shredded turf areas. Apply with Bark mulch blower, chip handler, or by hand. * When fiber mulch is the only available mulch during periods when straw should be used, apply at a minimum rate of 2000 lbs./ac. or 45 lbs./1000 sq. ft. Source: Va. DSWC III - 353 1992 3.35 Application: Mulch materials shall be spread uniformly, by hand or machine. When spreading straw mulch by hand, divide the area to be mulched into approximately 1,000 sq. ft. sections and place 70-90 lbs. (1 Z to 2 bales) of straw in each section to facilitate uniform distribution. Mulch Anchoring: Straw mulch must be anchored immediately after spreading to prevent displacement. Other organic mulches listed in Table 3.35-A do not require anchoring. The following methods of anchoring straw may be used: 1. Mulch anchoring tool (often referred to as a Krimper or Krimper Tool): This is a tractor-drawn implement designed to punch mulch into the soil surface. This method provides good erosion control with straw. It is limited to use on slopes no steeper than 3:1, where equipment can operate safely. Machinery shall be operated on the contour. 2. Fiber Mulch: A very common practice with widespread use today. Apply fiber mulch by means of a hydroseeder at a rate of 500-750 lbs./acre over top of straw mulch or hay. It has an added benefit of providing additional mulch to the newly seeded area. 3. Liquid mulch binders: Application of liquid mulch binders and tackifiers should be heaviest at edges of areas and at crests of ridges and banks, to prevent displacement. The remainder of the area should have binder applied uniformly. Binders may be applied after mulch is spread or may be sprayed into the mulch as it is being blown onto the soil. The following types of binders may be used: a. Synthetic binders - Formulated binders or organically formulated products may be used as recommended by the manufacturer to anchor mulch. * b. Asphalt - Any type of asphalt thin enough to be blown from spray equipment is satisfactory. Recommended for use are rapid curing (RC-70, RC-250, RC-800), medium curing (MC-250, MC-800) and emulsified asphalt(SS-1,CSS-1,CMS-2,MS-2,RS-1,RS-2,CRS-1, and CRS-2). Apply asphalt at 0.10 gallon per square yard (10 gal./1000 sq.ft. or 430 gal./acre). Do not use heavier applications as it may cause the straw to "perch" over rills. All asphalt designations are from the Asphalt Institute Specifications. * Note: This particular method is not used as commonly today as it once was in the past. The development of hydraulic seeding equipment promoted the industry III - 354 1992 3.35 to turn to synthetic or organically based binders and tackifiers. When this method is used, environmental concerns should be addressed to ensure that petroleum-based products do not enter valuable water supplies. Avoid applications into waterways or channels. 4. Mulch nettings: Lightweight plastic, cotton, or paper nets may be stapled over the mulch according to manufacturer's recommendations. 5. Peg and twine: Because it is labor-intensive, this method is feasible only in small areas where other methods cannot be used. Drive 8- to 10-inch wooden pegs to within 3 inches of the soil surface, every 4 feet in all directions. Stakes may be driven before or after straw is spread. Secure mulch by stretching twine between pegs in a criss-cross-within-a square pattern. Turn twine 2 or more times around each peg. Chemical Mulches Chemical mulches* may be used alone only in the following situations: a. Where no other mulching material is available. b. In conjunction with temporary seeding during the times when mulch is not required for that practice. c. From March 15 to May 1 and August 15 to September 30, provided that they are used on areas with slopes no steeper than 4:1,which have been roughened in accordance with SURFACE ROUGHENING, Std. & Spec. 3.29. If rill erosion occurs, another mulch material shall be applied immediately. * Note: Chemical mulches may be used to bind other mulches or with fiber mulch in a hydroseeded slurry at any time. Manufacturer's recommendations for application of chemical mulches shall be followed. Maintenance All mulches and soil coverings should be inspected periodically (particularly after rainstorms) to check for erosion. Where erosion is observed in mulched areas, additional mulch should be applied. Nets and mats should be inspected after rainstorms for dislocation or failure. If washouts or breakage occur, re-install netting or matting as necessary after repairing damage to the slope or ditch. Inspections should take place up until grasses are firmly established. Where mulch is used in conjunction with ornamental plantings, inspect periodically throughout the year to determine if mulch is maintaining coverage of the soil surface; repair as needed. III - 355 1992 3.02 STD & SPEC 3.02 TEMPORARY STONE CONSTRUCTION ENTRANCEISO Definition A stabilized stone pad with a filter fabric underliner located at points of vehicular ingress and egress on a construction site. Purpose To reduce the amount of mud transported onto paved public roads by motor vehicles or runoff. Conditions Where Practice Applies Wherever traffic will be leaving a construction site and move directly onto a public road or other paved area. :JS.iKF[*�*',"'.y" wh"'3,-� -- t S" v�' :' xE? ',`. , aye .g w. Y*. 5y a.-3 z .i-a i✓,"ri'. 46., r,Y :: N"' �� ^..,. 5 .z., a,c r l .,...,i".off' :"-,t �—olir IE :'„ < ,n ?�rRYu;z, �v , w .- F�.;`.'.��'«,. ''''r. NL.:o' `-':33 »^"- i � '"; Kra.. '!'4',ik.nr#-»yi :!°^,%,::.gye:w»..a'.R: p''s-mil.cn..z `° a. �„�.:,""`...�.`+- V. ' •:.rid' :. � x„� �`;F'".z,,,.x,kwsa°'^S -_s w .Sw��,, ,,,,,04,'.p yW4*'7,,,:.: 3C«s'.rt,,,''' .i.1 ,,,- ..�.`?Z'^"s.$^, '„Mv.,',,_�+..?,g 'R"+.?y" ! - 'a1- 4 15, •'.pi„' - „..w' ',.,„.r"v n, r''ti , '' vA Ro- ..i+.,ti '�ry +..;:5" % . ,:. - ,+ter . . 1 � a^ar•"..., r ^�, -: ":a ' ,,w" ``-! ,.»%•;°..wm ti "Am .r R. *".+,fife V K g.tackz '1",:z,,,4a^..„..., ,e ter.. 2 z "'- MC. ,rt i �,w „',a _,,tea A ,3. t s'w.'`e.. z ;„.c a q ,, ,,,,k yr w s ...s....,...,:-.:?..,...t.„...4,,..;,,....., .11-‘6"5"...k.- 3, 0-4 WD". . ,,.. .,.^ cg,., ^r,k�'N. 3, ,t.• "- ' *. `. _..._.:.� I.r -,...a.# ..w'�'...}.Y-.,'M„ O. �^ 2, ..` cKti�..W. '- " \" "'Y„' 'v ,i4�,.r n.x.. ..., ` It w :5' i»•"T"''v�,�' III - 6 1992 3.02 Planning Considerations Minimum Standard #17 (MS #17) requires that provisions be made to minimize the transport of sediment by vehicular traffic onto a paved surface. Construction entrances provide an area where a significant amount of mud can be removed from construction vehicle tires before they enter a public road and,just as important, the soil adjacent to the paved surface can be kept intact. A filter fabric liner is used as a "separator" to minimize the dissipation of aggregate into the underlying soil due to construction traffic loads. If the action of the vehicles traveling over the gravel pad is not sufficient to remove the majority of the mud or there exists an especially sensitive traffic situation on the adjacent paved road, the tires must be washed before the vehicle enters the public road. If washing is necessary, provisions must be made to intercept the wash water and trap the sediment so it can be collected and stabilized. Construction entrances should be used in conjunction with the stabilization of construction roads (see Std. & Spec. 3.03, CONSTRUCTION ROAD STABILIZATION) to reduce the amount of mud picked up by construction vehicles and to do a better job of mud removal. Other innovative techniques for accomplishing the same purpose (such as a bituminous entrance) can be utilized, but only after specific plans and details are submitted to and approved by the appropriate Plan-Approving Authority. Design Criteria Aggregate Size VDOT #1 Coarse Aggregate (2- to 3-inch stone) should be used. Entrance Dimensions • The aggregate layer must be at least 6 inches thick; a minimum three inches of aggregate should be placed in a cut section to give the entrance added stability and to help secure filter cloth separator. It must extend the full width of the vehicular ingress and egress area and have a minimum 12-foot width. The length of the entrance must be at least 70 feet(see Plate 3.02-1). Washing . If conditions on the site are such that the majority of the mud is not removed by the vehicles traveling over the stone, then the tires of the vehicles must be washed before entering the public road. Wash water must be carried away from the entrance to a approved settling area to remove sediment. All sediment shall be prevented from entering storm drains, ditches, or watercourses. A wash rack may also be used to make washing more convenient and effective (see Plate 3.02-1). Location The entrance should be located to provide for maximum utilization by all construction vehicles. III - 7 1992 3.02 Construction Specifications The area of the entrance must be excavated a minimum of 3 inches and must be cleared of all vegetation, roots, and other objectionable material. The filter fabric underliner will then be placed the full width and length of the entrance. Following the installation of the filter cloth, the stone shall be placed to the specified dimensions. If wash racks are used, they should be installed according to manufacturer's specifications. Any drainage facilities required because of washing should be constructed according to specifications. Conveyance of surface water under entrance, through culverts, shall be provided as required. If such conveyance is impossible, the construction of a "mountable" berm with 5:1 slopes will be permitted. The filter cloth utilized shall be a woven or nonwoven fabric consisting only of continuous chain polymeric filaments or yarns of polyester. The fabric shall be inert to commonly encountered chemicals and hydrocarbons, be mildew and rot resistant, and conform to the physical properties noted in Table 3.02-A. Maintenance The entrance shall be maintained in a condition which will prevent tracking or flow of mud onto public rights-of-way. This may require periodic top dressing with additional stone or the washing and reworking of existing stone as conditions demand and repair and/or cleanout of any structures used to trap sediment. All materials spilled, dropped, washed, or tracked from vehicles onto roadways or into storm drains must be removed immediately. The use of water trucks to remove materials dropped,washed, or tracked onto roadways will not be permitted under any circumstances. III - 8 1992 3.02 STONE CONSTRUCTION ENTRANCE 70' MIN. EXISTING a A 3. PAVEMENT ;'��:� ..5:1 I. -,Sig= -—r=._1J�i--- ti�i_!:---- -:�.- �,:, �-�, i 11. 11'�11 I 11 7 11r -'.. __:.:: ..-..ce.__.. —.. =.. . -_.. ._ .fir_-'.. _se:.,•,='n / FILTER CLOTH 6" MIN. A MOUNTABLE BERM (OPTIONAL) SIDE ELEVATION EXISTING GROUND 70' MIN. �•' 10' MIN, B WASHRACK .` C (OPTIONAL) '.•,',151.11i , IIt�y4; 10' MIN. n!�'�;:: 12' MIN.* Valk :'; �'.% 14-- EXISTING .��I: 7; ::r';;�;��,,,:: �t� PAVEMENT III ett i4 jr 'an.nl14-'4 .;:jl IIt1..f. �'•' .'•:'•:• :':•�•'c;.. sal.: Ili•.:A.A;; I. ,i..!.lf'.{f, = :L•.:I VDOT I I I t--\ POSITIVE DRAINAGE ' 10' MIN. COURSE AGGREGATE B TO SEDIMENT .4 TRAPPING DEVICE * MUST EXTEND FULL WIDTH OF INGRESS AND EGRESS PLAN VIEW OPERATION 12' MIN. •• a.._-_p4o.'t jm •• +w��.+`,�-`44 3" MIN. 10111111,. ll ar_.�a. 4,a`0141 �� ow`aetisi•'Av,. 3° MIN. FILTER CLOTH SECTION A-A 6'-7' ► Alrip glopar, ... spoor% ....,441 a��� .... . . .:.'.. . . ���. lar IF REINFORCED CONCRETE DRAIN SPACE SECTION B-B Source: Adapted from 1983 Maryland Standards for Soil Plate 3.02-1 Erosion and Sediment Control, and Va. DSWC III - 9 1992 3.02 TABLE 3.02-A CONSTRUCTION SPECIFICATIONS FOR FILTER CLOTH UNDERLINER Light-Duty y Heavy-Duty Fabric Entrance Entrance3 Test Properties1 (Graded Subgrade) (Rough Graded) Method Grab Tensile Strength (lbs.) 200 220 ASTM D1682 Elongation at Failure (%) 50 220 ASTM D1682 Mullen Burst Strength (lbs.) 190 430 ASTM D3786 Puncture Strength ASTM D751 (lbs.) 40 125 (modified) Equivalent Opening U.S. Standard Size (mm) 40-80 40-80 Sieve CW-02215 1 Fabrics not meeting these specifications may be used only when design procedure and supporting documentation are supplied to determine aggregate depth and fabric strength. 2 Light Duty Entrance: Sites that have been graded to subgrade and where most travel would be single axle vehicles and an occasional multi-axle truck. Examples of fabrics which can be used are: Trevira Spunbond 1115, Mirafi 100X, Typar 3401, or equivalent. 3 Heavy Duty Entrance: Sites with only rough grading and where most travel would be multi-axle vehicles. Examples of fabrics which can be used are: Trevira Spunbond 1135, Mirafi 600X, or equivalent. Source: Virginia Highway and Transportation Research Council (VHTRC) ' III - 10 1992 3.36 STD & SPEC 3.36 Treat. - l SOIL STABILIZATION or BLANKETS & MATTING M Treat. Definition The installation of a protective covering (blanket) or a soil stabilization mat on a prepared planting area of a steep slope, channel or shoreline. Purpose To aid in controlling erosion on critical areas by providing a microclimate which protects young vegetation and promotes its establishment. In addition, some types of soil stabilization mats are also used to raise the maximum permissible velocity of turf grass stands in channelized areas by "reinforcing the turf' to resist the forces of erosion during storm events. Conditions Where Practice Applies On short, steep slopes where erosion hazard is high and planting is likely to be too slow in providing adequate protective cover;in vegetated channels where the velocity of design flow exceeds"allowable"velocity; on streambanks or tidal shorelines where moving water is likely to wash out new plantings; or in areas where the forces of wind prevent standard mulching practices from remaining in place until vegetation becomes established. Mil. .+ ' , - �y ^ '-�� y r., • ye„ 4� ,.a ";,,. } •n t wq. - R Y . 1# A .,y"," . geyN °yy 'i • .b.6S�L.'`#``4'r?A. $• _ • �.s , _ • III — 356 1992 3.36 Planning Considerations Soil stabilization blankets and mats can be applied to problem areas to supplement nature's erosion control system (vegetation)in its initial establishment and in providing a safe and "natural" conveyance for high velocity stormwater runoff. They are being used today in many applications were previously a structural lining would have been required. Care must be taken to choose the type of blanket or matting which is most appropriate for the specific needs of a project. Two general types of blankets and mats are discussed within this specification. However, with the abundance of soil stabilization products available today, it is impossible to cover all the advantages, disadvantages and specifications of all manufactured blankets and mats. Therefore, as with many erosion control-type products, there is no substitute for a thorough understanding of the manufacturer's instructions and recommendations and a site visit by a designer or plan reviewer to verify a product's appropriateness. Treatment-1 is a degradable soil stabilization blanket which includes"combination"blankets consisting of a plastic netting which covers and is intertwined with a natural organic or man- made mulch; or, a jute mesh which is typically homogeneous in design and can act alone as a soil stabilization blanket. It should be used to help establish vegetation on previously disturbed slopes - normally problem slopes of 3:1 or greater. Since the materials which compose the soil stabilization blankets will deteriorate over time, they should be used in permanent conveyance channels with the realization that the system's resistance to erosion is based on the type of vegetation planted and the existing soil characteristics. During the establishment of vegetation, Treatment-1 should not be subjected to shallow or deep concentrated flows moving at greater than 4 feet/second. Treatment-1 provides the following benefits in the achievement of vegetative stabilization when properly applied over seed and required amendments: 1. Protection of the seed and soil from raindrop impact and subsequent displacement. 2. Thermal consistency and moisture retention for seedbed area. 3. Stronger and faster germination of grasses and legumes. 4. Planing off excess stormwater runoff. 5. Prevention of sloughing of topsoil added to steeper slopes. Treatment-2 is a soil stabilization matting which consists of a non-degradable,3-dimensional plastic structure which can be filled with soil prior to planting. This configuration provides a matrix for root growth where the matting becomes entangled and penetrated by roots, forming continuous anchorage for surface growth and promoting enhanced energy , III - 357 1992- 3.36 dissipation. Treatment-2 can be used on problem slopes (normally 3:1 or greater), and in stormwater conveyance channels. In addition to those benefits noted for Treatment-1, Treatment-2 provides the following benefits in the achievement of vegetative stabilization and in the replacement of more traditional channel linings such as concrete and riprap: 1. Causes soil to drop out of stormwater and fill matrix with fine soils which become the growth medium for the development of roots. 2. When embedded in the soil within stormwater channels, it acts with the vegetative root system to form an erosion resistant cover which resists hydraulic lift and shear forces. Since Treatment-2 is non-degradable, it can be used in permanent conveyance channels and can withstand higher velocities of flow than the vegetation and soil would normally allow. However, a 10 feet/second velocity of flow should be the maximum allowed in a conveyance system which utilizes Treatment-2. VDOT Nomenclature and Product Information The Virginia Department of Transportation has its own nomenclature for many of the standards and specifications found in this handbook; this is true in the case of soil stabilization blankets and matting. The following relationship exists between the two methods of naming the practice: Va. E&S-C Handbook VDOT Specifications Treatment-1 (is equivalent to) EC-2 Treatment-2 (is equivalent to) EC-3 It is recommended that most current VDOT "Approved Products List" for these products be consulted prior to installation of a particular blanket or mat. Importantly, the list names those products approved for a certain range of flow velocities when Treatment-2 (VDOT's EC-3) installation is contemplated. TREATMENT-1: SOIL STABILIZATION BLANKET (Allowable Velocity Range During Vegetation Establishment: 0 - 4 f.p.s.) Materials 1. Combination Blankets - They shall consist of a photo-degradable plastic netting which covers and is entwined in a natural organic or man-made mulching material. III - 358 1992 3.36 The mulching material shall consist of wood fibers, wood excelsior, straw, coconut fiber, or man-made fibers, or a combination of the same. The blanket shall be of consistent thickness with the mulching material/fibers evenly distributed over its entire length. The mulching material/fibers must interlock or entwine to form a dense layer which not only resists raindrop impact, but will allow vegetation to penetrate the blanket. The blanket shall be nontoxic to vegetation and to the germination of seed and shall not be injurious to the unprotected skin of humans. At a minimum, the plastic netting must cover the top side of the blanket and possess a high web strength. The netting shall be entwined with the mulching material/fiber to maximize strength and provide for ease of handling. 2. Jute Mesh - It shall be of a uniform, open, plain weave, of undyed and unbleached single jute yarn. The yarn shall be of loosely twisted construction and shall not vary in thickness by more than one half of its normal diameter. Jute mesh shall be new and shall conform to the following: a. Length of jute mesh shall be marked on each roll. b. There shall be 0.60-inch openings (± 25%) between strands, lengthwise. c. There shall be 0.90-inch openings (± 25%) between strands, lengthwise. d. Weight shall average 0.90 lbs./square yard with a tolerance of 5%. As previously noted, jute mesh provides such good coverage (large surface area of strands) and contains such small openings that it can be used alone as a blanket. 3. Other Treatment-1 Products - These shall conform to manufacturer's specifications and be approved by the Plan-Approving Authority prior to being specified for a particular application. These products should be installed in accordance with manufacturer's recommendations, provided those recommendations are at least as stringent as this specification. Again, it is recommended that VDOT's "Approved Products List" be consulted. In no case shall these products cover less than 30% of the soil surface. 4. Staples - Staples for anchoring Treatment-1 shall be No. 11-gauge wire or heavier. Their length shall be a minimum of 6 inches. A larger staple with a length of up to 12 inches should be used on loose, sandy, or unstable soils. III - 359 1992 3.36 ' Installation Requirements Site Preparation - After site has been shaped and graded to approved design, prepare a friable seedbed relatively free from clods and rocks more,than 11/2 inches in diameter and any foreign material that will prevent uniform contact of the protective covering with the soil surface. Planting - Lime, fertilize, and seed in accordance with seeding or other type of planting plan. When using jute mesh on a seeded area, apply approximately one-half the seed after laying the mat. The protective covering can be laid over sprigged areas where small grass plants have been inserted into the soil. Where ground covers are to be planted, lay the protective covering first and then plant through the material as per planting design. When open-weave nets are used, lime, fertilizer, seed and mulch should be applied before laying the net. When a combination blanket (such as an "excelsior" blanket) is used, seed and soil amendments must also be applied before the blanket is laid. Orientation - See Plate 3.36-1 for orientation of Treatment-1 for different topographic conditions. Laying and Stapling (see Plate 3.36-2) -If instructions have been followed, all needed check slots will have been installed, and the protective covering will be laid on a friable seedbed free from clods, rocks, roots, etc. that might impede good contact. 1. Start laying the protective covering from the top of the channel or top of slope and unroll down-grade. 2. Allow to lay loosely on soil - do not stretch. 3. Upslope ends of the protective covering should be buried in a anchor slot no less than 6-inches deep. Tamp earth firmly over the material. Staple the material at a minimum of every 12 inches across the top end. 4. Edges of the material shall be stapled every 3 feet. Where multiple widths are laid side by side, the adjacent edges shall be overlapped a minimum of 2 inches and stapled together. 5. Staples shall be placed down the center, staggered with the edges at 3 foot intervals. Check slots - On highly erodible soils and on slopes steeper than 4:1, erosion check slots should be made every 50 feet (see Plate 3.36-2). Insert a fold of the material (separate piece) into a 6-inch trench and tamp firmly. Staple fold to "main" blanket at minimum 12- inch intervals across the upstream and downstream portion of the blanket. III - 360 1992 3.36 TYPICAL ORIENTATION OF TREATMENT - 1 (SOIL STABILIZATION BLANKET) SHALLOW SLOPE - -- • ;;•y•:::_t- •--"-"--<<�- ON SHALLOW SLOPES STRIPS OF • -- -••- +,`�s ••: " L NETTING PROTECTIVE COVERINGS •'"•••' �`' .MAY BE APPLIED ACROSS 1 11= •:� %;•h.';o�:_ " THE SLOPE. III�III�11 BERM u-n-n-_ WHERE THERE IS A BERM AT THE TOP OF THE SLOPE, I 11=1T=. JI. .II71k�'�, BRING THE MATERIAL OVER THE BERM AND ANCHOR IT 1"I�11 .1111=11-11, BEHIND THE BERM. I LI11II�.14.11-'f 11�II ill 11.=JL= =,11I —11=11. 1_I1==I1�= - STEEP SLOPE 1�1•1••�N9. *:• '*N::;y : 5 i STEEP SLOPES, APPLY -- %% �'�� : c''==== - - PROTECTIVE COVERING PARALLEL =11=jwii+•• + � ' i� TO THE DIRECTION OF FLOW =111.0:0.ii++i++i�'"��_„_,�' AND ANCHOR SECURELY. • • 11=0ti+.4,i C�!���++ II 11=11=11=11=111= -11.—,D 11-71 — 4 • BRING MATERIAL DOWN TO A LEVEL AREA BEFORE • `' ` `' "• TERMINATING THE INSTALLATION. TURN THE END UNDER 4" AND STAPLE AT 12" INTERVALS. DITCH iS%4•,fii��/// FLOW 11.4,•ittZ •'�i�1♦I Ir;/�/! 1 1/1iDit4,i' 4/1 Pan . ,•••♦♦♦4'Z' !1 1 1r1f�1�'I .aaa. IN DITCHES, APPLY PROTECTIVE COVERING .`��j1♦ Iq II / r•+4sff17 I'I �Nua•C '"1♦• ♦♦• o II /11 pig 1 au.' PARALLEL TO THE DIRECTION OF FLOW. •�•♦♦ ♦ V4 ! r' �• • ice%♦♦♦�♦♦�•,s,AlIs�I irlfs�;;�`'�l`;li1., USE CHECK SLOTS AS REQUIRED. AVOID �•�••♦!r`, , oret.,'iilil • ' JOINING MATERIAL 1N THE CENTER OF •_ �������41,Vei♦i;jij4 1$141j!',Ijitill""'ll`•l THE DITCH IF AT ALL POSSIBLE. _=1L�AAA���0;,fiiYMMM isssssusf%/0 401, ::.+ 1•;. %��!•"�/ :fluff,�e.1 Aloop 1J II 141. n. issilll J1=ll �J =m=if==H-I1=H]I=1f. 11— -l lh11 11.#11.;Il.JL Source: Adapted from Ludlow Products Brochure Plate 3.36-1 III '- 361 1992 3.36 TYPICAL TREATMENT - (SOIL. STABILIZATION BLANKET) INSTALLATION CRITERIA ,, � ANCHOR SLOT „ ; ?, ;, NOTES %' ,'/ %' . APPROXIMATELY 200 STAPLES REQUIRED ,,," ;;. PER 100 SQ. YDS. OF MATERIAL ROLL. ,e0,, %/i� 4" ANCHOR SLOTS, JUNCTION SLOTS & . '''''. • ' CHECK SLOTS TO BE BURIED 6" TO 12". %� 12" MAX. 4:1 OR FLATTER %^' S MAX. STEEPER THAN 4:1 ,OP, .' '/ ( y" JUNCTION SLOT EDGE AND END JOINTS TO BE SNUGLY ABUTTED I I I CHECK SLOT SW.' �RMI FOLD STAPLED LAP JOINT IN bill I I LIEU OF EDGE JOINT) LAP JOINT 2 MIN. I TAMP FIRMLY (JUTE MESH ONLY) I I I I ANCHOR SLOT 5' MAX. 4:1 OR FLATTER 3' MAX. STEEPER THAN 4:1 I I I II=11lllf-L'll 2" 11 111111=11=11 II'11111 noEn"u=u=a-1-u-1 6" TO 12" II=I1 1.-�=.11=11=11 II I I I I =11=11:II II=11=11=1-II=1 I I I I = - -11 II-1 I I -- lull I I I I *CHECK SLOT I I I I I 1 I I 1 1 I I- F " k- 1" TO 2" I _ TAMP CHECK SLOT I I I 111.111 FIRMLY u•11!- VAR. VAR. 6.1 �1"' 8" To 12- 6" TO 8" MIN. PLAN VIEW 11 11=11 1Lu-II. =111'.11=11 1,L-1r STAPLING DIAGRAM ii---a,kill1,- ii -j u=it �:1=�1=1L=1L II 1=11=11=11=11:_II_11_11=11=I=11=11=11=11 11-11-11-11-1-11=1=11=u -11-u-11=11-11 _i_ STAPLE FORMED FROM NO.11 STEEL WIRE. *CHECK SLOTS AT MIN. 8" STAPLE MIN. LENGTH FOR SANDY SOIL. NO C-C INTERVALS; ALL 6" STAPLE MIN. LENGTH FOR OTHER SOIL NOT REQI'D B WITH "COMBINATION"BLANKETS JUNCTION SLOT ..,4.- TAMP TERMINAL FOLD 2" 12" FIRMLY Ti- 6" TO 12 - TAMP FIRMLY 2" Fos---- 4" --0..-1 i-ii .-1111=1=11=11=11,'11=111�1= = 111=11. 1111. Ir 1=11=II 0=11=:11=11=11=.1=11=11-11= 1J7-11" 11" II=11=11=11=1 II=11=I1-11=11=11r=I1 11=1P p=n—i 1111=111 111h 11=J111T1=11 11=11 11.1111 III IIII111"IiI111nII11'1=11GII�11 111111 =II=11=1 Source: VDOT Road and Bridge Standards Plate 3.36-2 III - 362 1992 3.36 Note: Many combination blankets are designed and manufactured to resist movement and uplift to a point which check slots may not be required. Plan designers and review authorities are urged to study manufacturers' recommendations and site conditions. Joining Protective Coverings - Insert a new roll of material into an anchor slot, as with upslope ends. Overlap the end of the previous roll a minimum of 12 inches, and staple across the end of the roll just below the anchor slot and across the material every 12 inches. Terminal End - At the point at which the material is discontinued, or at which time the protective covering meets a structure of some type, fold 4 inches of the material underneath and staple every 12 inches (minimum). At bottom of slopes - Lead net out onto a level area before anchoring. Turn ends under 4 inches, and staple across end every 12 inches. Final Check - These installation techniques must be adhered to: 1. Protective blanket is in uniform contact with the soil. 2. All lap joints are secure. 3. All staples are driven flush with the ground. 4. All disturbed areas have been seeded. TREATMENT-2: SOIL STABILIZATION MATTING (Allowable velocity range after vegetative establishment: 0 - 10 f.p.s.) Materials Matting - The majority of these products provide a three dimensional geomatrix of nylon, polyethylene, or randomly oriented monofilaments,forming a mat. These products contain ultra violet (UV) inhibiting stabilizers, added to the compounds to ensure endurance and provide "permanent root reinforcement." The three dimensional feature creates an open space which is allowed to fill with soil. The roots of the grass plant become established within the mat itself, forming a synergistic root and mat system. As the grass becomes established, the two actually "reinforce" each other, preventing movement or damage to the soil. Allowable velocities are increased considerably over natural turf stands. Selection of the appropriate matting materials along with proper installation become critical factors in the success of this practice. VDOT's "Approved Products List" can be a real asset in the selection process. Consultation with the supplier or the manufacturer and thorough III - 363 1992 3.36 • evaluation of performance data to ensure proper selection of a soil stabilization matting are also essential. Although many manufacturers claim their products may inhibit erosion associated with channel velocities of up to 20 ft./sec., it is recommended that any velocities that exceed 10 ft./sec. be properly protected with some form of structural lining (see Std. & Spec. 3.17, STORMWATER CONVEYANCE CHANNEL). Staples - Staples or anchoring methods and recommendations vary by manufacturers. The expectation of high velocities should dictate the use of more substantial anchoring. Some of the typically recommended stakes, staples and pins are depicted in Plate 3.36-3 STAKES, STAPLES, & PINS FOR INSTALLATION OF TREATMENT - 2 SOIL STABILIZATION MATTING 3-1/4 WA2"SHEDIA R 18" 10" MIN. 3/16' DIA. 1" STEEL PIN 1) 1x4 TRIANGULAR SURVEY STAKE - MINIMUM 10" IN LENGTH. PLACEMENT OF THE STAKE 6» ACROSS THE FLOW OF THE WATER IS THOUGHT STAKE I PIN TO SLLOWRTTHE VEA LOCITY"PINBALL EFFECT" TO HELP 2) 11 GAUGE STEEL - MINIMUM 1" WIDE BY 6" 11 GAUGE STEEL IN LENGTH STEEL STAPLE - 2"x8" STAPLE 6"x1"x6" STAPLE MAY BE REQUIRED IN CERTAIN SOIL CONDMONS. STAPLE 3) STEEL PINS - 3/16 DIAMETER STEEL PIN BY 18" IN LENGTH WITH A 2" DIAMETER WASHER ON TOP. (SEE ILLUSTRATION) Source: Product literature from Greenstreak, Inc. Plate 3.36-3 Installation Requirements Site Preparation - After site has been shaped and graded to approved design, prepare a friable seedbed relatively free from clods and rocks more than 1 inch in diameter, and any foreign material that will prevent contact of the soil stabilization mat with the soil surface. If necessary, redirect any runoff away from the ditch or slope during installation. III - 364 1992 3.36 Planting- Lime,fertilize and seed in accordance with MS#1 and the approved plan,paying special attention to the plant selection that may have been chosen for the matted area. If the area has been seeded prior to installing the mat, make sure and reseed all areas disturbed during installation. Mulching - Mulch (normally straw) should be applied following installation of Treatment-2 at rates noted in Std. & Spec. 3.35, MULCHING. Laying and Securing-See Plates 3.36-4,3.36-5 and 3.36-6. Similar to installing Treatment-1, but Plan Approving Authority's requirements or manufacturer's recommendations must be followed as detailed. The key to achieving desired performance is dependent upon proper installation. Check Slots - See Plate 3.36-4. Matting manufacturers vary significantly in their check slot requirements. Similar to the installation of Treatment-1,a check slot may be required when laying Treatment-2 to "correct" the flow of water if it has the potential to undermine the matting. Most authorities (including VDOT) require that the sides of the matting also be entrenched,creating a slope shelf for the material to rest on,preventing water from entering under the mat on the sides. Securing the Material and Joining Mats -Again, product specifications vary-upstream and downstream terminal slots, new roll overlaps and multiple width installations differ by various products and manufacturers. Final Check - These installation techniques must be adhered to: 1. Soil stabilization mat is in uniform contact with the soil. 2. All required slots and lapped joints are in place. 3. The material is properly anchored. 4. All disturbed areas are seeded. Maintenance All soil stabilization blankets and matting should be inspected periodically following installation, particularly after rainstorms to check for erosion and undermining. Any dislocation or failure should be repaired immediately. If washouts or breakage occurs, re- install the material after repairing damage to the slope or ditch. Continue to monitor these areas until which time they become permanently stabilized; at that time an annual inspection should be adequate. III - 365 1992 3.36 'TYPICAL TREATMENT-2 SOIL STABILIZATION MATTING INSTALLATION SOIL STABILIZATION MATTING SHALL BE USED IN CONJUNCTION WITH RIP RAP AT OUTLET END OF PIPE. ��W illie .orr •Ve \a 41 l,�1 _.,,,,,,t\—(C3-. ' \ \ \ i la 41* . ..040,e; - - / iiiks. 71.+. - r _t ENTRENCH EDGES \\ / OF MATERIAL .......... //.--"...--• 4•41•1 ,�; CHECK SLOTS TO BE -�I_ r CONSTRUCTED AS PER I � 5' aft.. MANFACTURERS RECOMMENDATIONS. y, 1'-2' IN� 4 TRANSVERSE :. f i' f:. CLOSED CHECK SLOT --•1-: -.'E.-•'--': r.. FLOW . " ;I .• ivi .:.. .-a UPSTREAM AND FLOW 1.-2' �•.-- . .} DOWNSTREAM �::: TERMINAL iepP.-.:;..r.fr:L, �► : �+', OPEN ICHE K SLOT �/.� .�i��� •  V � NO *` ,/ Source: VDOT Road and Bridge Standards Plate 3.36-4 III - 366 1992 3.36 TYPICAL TREATMENT - 2 SOIL STABILIZATION MATTING SLOPE INSTALLATION • FILL SLOPE SECTIONS SOIL STABILIZATION MATS SHOULD �� �QQ� BE INSTALLED VERTICALLY Q NOTE; SLOPE SURFACE DOWNSLOPE FOR BEST RESULTS. /// Q S /r SHALL BE SMOOTH / Xii AND FREE OF /p Q ROCKS, LUMPS OF DIRT, GRASS AND 67 Q / / STICKS. MAT SHALL -� 5' / BE PLACED FLAT / q ON SURFACE FOR 1/` Q-.. PROPER SOIL r,�,;l CONTACT. 0 Q i1j:4 Q S�3v y 4 va. / i OVA @~ Q P�� �!:::.. . 'Mt �� Q DIRT SHALL BE TAMPERED PRIOR = ~� TO LAYING TOP j .11 �� LAP OVER TOE BERM MAINTAIN SLOPE ANGLE TRENCH INTO BERM AND PROGRESS DOWNSLOPE SLOPE LINING SLOPE LINING TOP SF CUT SLOPE (WET SLOPE) „1- (DRY SLOPE) �,��� -R=II 1r.:.R- IL JI u TREATMENT - 2 f�i� - .�i° POLYPROPELYENE All ll 2' NON-WOVEN II- II- (NEEDLE PUNCHED) j R p�OVR TREATMENT - 2 .. GEOTEXi1LE FILTER 11 �L� S Gf�6RlAii CLOTH (BEHIND j_._9 : P8O • LP' -nor TREATMENT - 2) "_ f WAS ,14= 3 1 :� Ir. SOIL 11- BOTTOM OF ALL SLOPE Mill _ = _ —'=u=uI_ I1= -II:-n �� n%-u 1 BOTTOM OF CUT SLOPE I. BOTTOM OF CUT SLOPE 4'OR SHOULDER BREAK POINT Source: VDOT Road and Bridge Standards Plate 3.36-5 III - 367 0 0 _ GENERAL STAPLE PATTERN GUIDE N :� AND RECOMMENDATIONS � G FOR TREATMENT - 2 r. (SOIL STABILIZATION MATTING) CD 1v TX X I CD Nh W X XX0 IX 0 IX 300 u+ w-..' 275 x X {: 250 I X 225 B C X 1, 1 CD A 200C W ti 175 C C X X 00 X 150 B C 125 N 1 STAPLE PER SQ. YD. 100 2 STAPLES PER SQ. YD. n 75 A x x x x{ xT 50 r j 25Fr A B g X �XNX� XTX� o t T " X� Xx x X x X� u 4:1 3:1 2:1 1:1 FLOW MED. / HIGH 1 1/2' r 1 1/2' CHANNEL CHANNEL AND SHORELJNE x B NOTE: FOR OPTIMUM RESULTS, THESE RECOMMENDED D ' , STAPLE PATTERN GUIDES MUST BE FOLLOWED. SUGGESTED ANCHORING METHODS VARY rD x X ACCORDING TO THE MANUFACTURER. THIS 1 1 2 STAPLES PER SQ. YD. CHART SHOWS HOW SLOPE LENGTHS AND W GRADIENTS AFFECT STAPLING PATTERNS. 3 1/2 STAPLES PER SQ. YD. W W 0 W CT 1992 3.31 STD & SPEC 3.31 © - TEMPORARY SEEDING4ID Definition The establishment of a temporary vegetative cover on disturbed areas by seeding with appropriate rapidly growing annual plants. Purposes 1. To reduce erosion and sedimentation by stabilizing disturbed areas that will not be brought to final grade for a period of more than1rdays. fWE• iccY-pr ' "f 13-i.• 2_19 2. To reduce damage from sediment and runoff to downstream or off-site areas, and to provide protection to bare soils exposed during construction until permanent vegetation or other erosion control measures can be established. r‘,---.,,,...,--\.14-:-.:4;;-..,,,-,,...... ,.." , -...1,,,,, ,,,,4-64„1.1$; - 4...4.:,....17";74).:A',- - , erka44-A, - -' ” ..i.i:F, !firt. r.` s.•— „.. 4.0 ,..,..,c„. .,, c� , `a'i..!, <fit fit'* �t �. Q ,es' j!j ei, �•'+, r "�.�'4: '`3.•r ,I a .:- --..?-.7r. t •it,. ,,- n'�4'T"y_"`f.•.;`. 34 -�, G�'K F y `t �,��, ,Y .. ?'`^�"`S.`};°ntj's "Fy�.'rrf - ,^ y4 .0 :a Y';;. '- -i..v",..',11; l'''-"''' "'t-',-; .3'40- Ct.-- :, '-'-`-v,,t-,, „,, ,..,s.,tot::',.,..-..,-.,..i. 1,, r-,5•.,',-,:41,"-..),, :f,,,,i0d;F--,i,gi, , \ „,... -4,..k ; 4,4 cif ast.. ,,, -A.",•.% _-„7 ,.*./ 4:,4*.7.4,kilrf,- ..?,,z_7.-- ,f.i: i , ` ist 1..A .,,,-- n r �?}� n... �y, _.. t • is r ys ,. 4' Yf _%i �7%, Y ��t if ...1 g i `..."2>f ... it,. i'CAA + ~•yp14 •�e. �,_f , 1. a. .g`fti' "fr. , , _Ur? i' '�,+� -":may ,,-R, i "X, It. ask, . 4 .- Agli.4111 **0 Vit',..ri "Pris'. 1AS I, .. d d QA . .r, I 1 c J 5 :ta ,r -t .. s'•r' 'i`. 9 !�.%i SS ,F� •!R. t,- sF „`Q _,,t t jKd V f.�x�y; t R.Y �.� Cam. ,-.4-mii �- Yk :' s:' a .` , •.e. r,,. ,, :S .tiw. fr.. .PI:J ,, ' ` -- ..+ ch 4"ii 4 rF :s*.••=yam . a`� ! 1. e �:, r'( ^+ .„. .{_.air ` ¢iE i e.: r, = ?fit f•' ��c+ , �J.p,..1 ..: r y.f.$ r r c`}, 03, F• f ; ' .a 1D i Kz� ` rr. � ^�}f 1 r':•r i i�' w. 'K Fry sg Y r'� i.Y .'X'.• '. ' ` '... �a Y t'; 4JC' ".i ' 4H "yJi7 r I R.4 J + -iiv ' Ot i stio e'S. I r '• :s. k ,�, s xi. n'r -'. } .qua - C, r a" y,rE". ) T F ajj)) Ay ' -'4- �y w";){ 7 57:At'"i ,44 4,.'rE , ,s,s ,. '.Y ✓ 1:1:2..,,..2 :..,.1' . .,.'Z'I',:i t ,E 7,u,e,;, i= F � ,' III - 284 1992 3.31 Conditions Where Practice Applies tl nor' be a}- Ft rAke more-I-114A ly delS, w'i q flgCr�' A Where exposed soil surfaces b r days. Such areas include denuded areas, soil stockpiles, dikes, dams, sides of sediment basins, temporary roadbanks, etc. (see MS #1 and MS #2). A permanent vegetative cover shall be applied to areas that will be left dormant for a period of more than 1 year. Planning Considerations Sheet erosion, caused by the impact of rain on bare soil,,is the source of most fine particles in sediment. To reduce this sediment load in runoff, the soil surface itself should be protected. The most efficient and economical means of controlling sheet and rill erosion is to establish vegetative cover. Annual plants which sprout rapidly and survive for only one- growing season axe suitable for establishing temporary vegetative cover. Temporary seeding is encouraged whenever possible to aid in"controlling' construction sites. • Temporary seeding also prevents costly maintenance operations on other erosion control - systems. For example,sediment basin clean-outs will be reduced if the drainage area of the basin is seeded where grading and construction are not taking place. Perimeter dikes will be more effective if not choked with sediment. Temporary seeding is essential to preserve the integrity of earthen structures used to control sediment, such as dikes, diversions, and the banks and dams of sediment basins. . Proper seedbed preparation and the use of quality seed are important in this practice just as in permanent seeding. Failure to carefully follow sound agronomic recommendations will often result in an inadequate stand of vegetation that provides little or no erosion control. Specifications Prior to seeding, install necessary erosion control practices such as dikes, waterways, and basins. Plant Selection Select plants appropriate to the season and site conditions from Tables 3.31-B and 331-C. Note that Table 3.31-B presents plants which can be used without extensive evaluation of site conditions; Table 3.31-C presents more in-depth information on the plant materials. Seedbed Preparation -__ __ . . -— _._ _... _. _..._... .____ _. _ To control erosion on bare soil surfaces, plants must be able to germinate and grow: Seedbed preparation is essential. 111 - 285 1992 3.31 1. Liming: An evaluation should be conducted to determine if lime is necessary for temporary seeding. In most soils, it takes up to 6 months for a pH adjustment to occur following the application of lime. Therefore, it may be difficult to justify the cost of liming a temporary site, especially when the soil will later be moved and regraded. The following table may be used to determine the actual need along with suggested application rates. TABLE 3.31-A LIMING REQUIREMENTS FOR TEMPORARY SITES Recommended Application pH Test of Agricultural Limestone • below 4.2 3 tons per acre 4.2 to 5.2 2 tons per acre 5.2 to 6 1 ton per acre • • Source: Va. DSWC 2. Fertilizer: Shall be applied as 600 lbs./acre of 10-20-10 (14 lbs./1,000 sq. ft.) or equivalent nutrients. Lime and fertilizer shall be incorporated into the top 2 to 4 inches of the soil if possible. 3. Surface Roughening: If the area has been recently loosened or disturbed,no further roughening is required. When the area is compacted, crusted, or hardened, the soil surface shall be loosened by discing, raking, harrowing, or other acceptable means (see SURFACE ROUGHENING, Std. & Spec. 3.29). 4. Tracking: Tracking with bulldozer cleats is most effective on sandy soils. This practice often causes undue compaction of the soil surface, especially in clayey soils, and does not aid plant growth as effectively as other methods of surface roughening. Seeding Seed shall be evenly applied with a broadcast seeder, drill, cultipacker seeder or hydroseeder. Small grains shall be planted no more than 12 inches deep. Small seeds,such . as Kentucky Bluegrass, should be planted no more than 1/4 inch deep. Other Grasses and Legumes should be planted from 1/4 inch to 1/2 inch deep: III -286 1992 3.31 Mulching 1. Seedings made in fall for winter cover and during hot and dry summer months shall be mulched according to MULCHING, Std. &Spec.3.35, except that hydromulches (fiber mulch) will not be considered adequate. Straw mulch should be used during these periods. 2. Temporary seedings made under favorable soil and site conditions during optimum spring and fall seeding dates may not require mulch. Re-seeding • Areas which fail to establish vegetative cover adequate to prevent rill erosion will be re- seeded as soon as such areas are identified. • TABLE 3.31-B • ACCEPTABLE TEMPORARY SEEDING PLANT MATERIALS "QUICK REFERENCE FOR ALL REGIONS" • Rate Planting Dates Species (lbs./acre) Sept. 1 - Feb. 15 50/50 Mix of Annual Ryegrass (Lolium multi-forum) & 50 - 100 Cereal (Winter) Rye • (Secale cereale) Feb. 16 - Apr. 30 Annual Ryegrass 60 - 100 (Lolium multi-forum) May 1 - Aug 31 German Millet 50 (Setaria italica) • Source: Va. DSWC III -287 TABLE 3.31-C TEMPORARY SEEDING PLANT MATERIALS, SEEDING RATES, AND DATES • • SEEDING RATE NORTH' SOUTHb i° PLANT SPECIES 3/1 5/1 8/15 2/15 5/1 9/1 CHARACTERISTICS Acre 1000 ft2 to to to to• to to 4/30 8/15 11/1 4/30 9/1 11/15 OATS 3 bu. (up to 100 lbs., 2 lbs. X - - X - - Use spring varieties(e.g., Noble). Avena saliva) not less than 50 lbs.) RYEd 2 bu. (up to 110 lbs., 2.5 lbs. X - X X - X Use for late fall seedings, winter Secale cereale not less than.50 lbs.) cover. Tolerates cold and low moisture. GERMAN MILLET 50 lbs. approx. 1 lb. - X - - X - Warm-season annual. Dies at first E Setaria italics) frost. May be added to summer mixes. ANNUAL RYEGRASS° 60 lbs. 11/2 lbs. X - X X - X May be added in mixes. Will Lolium multi-florum) mow out of most stands. WEEPING 15 lbs. 5'h ozs. - X - - X - Warm-season perennial. May LOVEGRASS bunch. Tolerates hot,dry slopes Era rostis curvula and acid, infertile soils. May be added to mixes. KOREAN 25 lbs. approx. 1'h X X - X X - Warm season annual legume. LESPEDEZA° lbs. Tolerates acid soils. May be (Lespedeza sti ulacea added to mixes. a Northern Piedmont and Mountain region. See Plates 3.22-1 and 3.22-2. b Southern Piedmont and Coastal Plain. e May be used as a cover crop with spring seeding. d May be used as a cover crop with fall seeding. X May be planted between these dates. co - May not be planted between these dates. '-- i 1992 3.13 STD & SPEC3.13 -a-ii - TEMPORARY SEDIMENT TRAPCil Definition A temporary ponding area formed by constructing an earthen embankment with a stone outlet. Purpose To detain sediment-laden runoff from small disturbed areas long enough to allow the majority of the sediment to settle out. Conditions Where Practice Applies 1. Below disturbed areas where the total contributing drainage area is less than 3 acres. • 4` `.A: . . � z; .,. .: ', • [ VOW , . . . ' ' .-. -- �` P47-4-...-- '',— ;�•ew- J:: "4N".s.,-:�.m�9;« ,ids fy` -,ww,. ,w n .� p"P'g(f '`' - f�°�A,�.���,,v as'. Y '� w,� !. r, • • ,b �' ' aL .wi•,., .. ,,�,. b ••,:.u 9%.;ia4.w:,� :.< yam, '4 y�+,`:'F 'rv'x'a x. ro ',,, wY,./�.. ,,,,,,,› 0t1.,. ,..„,X. 7,,,,a, »,,,,,,,,:1'- - C:i4,-4- , zy'x. ' 4 fir' ' Mr � `�» ',� .�'.,•.ac N 4�• '^�"�.,�"" �` " °` r�° ,.u�° ..�.^�.'��kae'-.,�,.ra�.�' '� :6,� »,, : �'� , roz a��� +ate- �q .». , J'''r _.,.. ,.a sr - • . ` r ."' � N ' ,- r-,':wr"te ' sw. tom ",- .� f =,"s , ' <.0. em .;s ,,,,' • 'q}p".✓#., Y'<, f +/'' a*r +M' 'YP• 1 ,,,' YYI.•^a' T:.'.•t-t., .' P' -e-••••• ..y V"i.TM'''' r 4\„a.£ • ^`..- °..- -X"`lyC ,,• g :...r".r'. !0: ..,„,,- .-,-1 w-=,4'r,V, tea' •'n't•- • M•Fs to, ..I'..a.1tJ•^.n„__''''" w? ,4'3 - '§`_Yw. .' , d a 6.'m/` . :'''-1,•7 �.-, .+"'+a,n,;�4.,,,ftg `kj 7;*•., ,,z9., ✓' a. w, .• 16. '«: °,,.w *', � ^n , y�r. :w,Y..'.,$:.. ,e t".V`ya..;• �ti ., ^'..ia ✓ •-„' r<i. •^,s r s..es ..,.,�",-,' ; .mow -«M1..? '''' •"4— Y ,�A ';Z4,4.e.,',. „ ..._ 1, c ..., -bye L`R�•n'4' ".,, .<` ' ,• , w h"�, ell ,, - '4E w, s,tr' .r„i.Y b. ..,, ,s4• 4� i "'•^.. '''' .. t°"kw p,,,, n*t." .s». *. ++ ,�, > 'f.a�*S`i� ,,alb+�r y- *� ,,k'9. °.C•s.. aa�.,sts4 '"',� �o�,`'�wwa,; „'. • ^' rb^��Tw-� ,,,, s ✓r, .,� , ,♦ ? .i,,,e`er. . . ,Are -.;',�: ak, :N: . ,,. J 3...'...., - ig' .: ..._- ., .•',n,. ;..'Shea:�'.' '•�48_'..�""'.a'�'- III - 70 1992 3.13 2. Where the sediment trap will be used no longer than 18 months (the maximum useful life is 18 months). 3. The sediment trap may be constructed either independently or in conjunction with a TEMPORARY DIVERSION DIKE (Std. & Spec. 3.09). Planning Considerations Sediment traps should be used only for small drainage areas. If the contributing drainage area is 3 acres or greater, refer to SEDIMENT BASIN (Std. & Spec. 3.14). Sediment traps, along with other perimeter controls intended to trap sediment, shall be constructed as a first step in any land-disturbing activity and shall be made functional before upslope land disturbance takes place. Recent studies have been conducted on the performance of sediment traps (and basins) which were constructed using the design criteria found in previous editions of this handbook. The studies indicate that the control measures only achieved a 46% removal of sediment which flowed into them during storm events which caused measurable outflow. To achieve a more acceptable removal rate (60%), it was necessary to revise the design of these measures in this handbook. The total initial storage volume for both the sediment trap and the TEMPORARY SEDIMENT BASIN (Std. & Spec. 3.14) has been doubled. There are both a"wet"storage volume and a drawdown or"dry"storage volume which help to enhance sediment fall-out and prevent excessive sediment losses during large storm events which occur during the advanced stages of land disturbance (28). In most cases excavation will be required to attain the necessary storage volume.. Also, sediment must be periodically removed from the trap to maintain the required volume. Plans should detail how excavated sediment is to be disposed of, such as by use in fill areas on site or removal to an approved off-site location. As noted previously in this handbook, there are numerous other acceptable ways to design many of the erosion control practices within. This is certainly true in the case of the sediment trap. However, variations in its design should be considered judiciously by plan reviewers to ensure that the minimum storage requirements and structural integrity noted in this specification are maintained. Design Criteria Trap Capacity The sediment trap must have an initial storage volume of 134 cubic yards per acre of drainage area, half of which shall be in the form of a permanent pool or wet storage to provide a stable settling medium. The remaining half shall be in the form of-a drawdown III - 71 1992 3.13 or dry storage which will provide extended settling time during less frequent, larger storm events. The volume of the wet storage shall be measured from the low point of the excavated area to the base of the stone outlet structure. The volume of the dry storage shall be measured from the base of the stone outlet to the crest of the stone outlet (overflow mechanism). Sediment should be removed from the basin when the volume of the wet storage is reduced by one-half. For a sediment trap, the wet storage volume may be approximated as follows: Vi = 0.85 x AI x Dl where, Vi = the wet storage volume in cubic feet Al = the surface area of the flooded area at the base of the stone outlet in square feet Di = the maximum depth in feet, measured from the low point in the trap to the base of the stone outlet The dry storage volume may be approximated as follows: V = Al + A2 x D z 2 2 where, V2 = the dry storage volume in cubic feet Al = the surface area of the flooded area at the base of the stone outlet in square feet A2 = the surface area of the flooded area at the crest of the stone outlet (overflow mechanism), in square feet D2 = the depth in feet, measured from the base of the stone outlet to the crest of the stone outlet The designer should seek to provide a storage area which has a minimum 2:1 length to width ratio (measured from point of maximum runoff introduction to outlet). III - 72 1992 3.13 Note: Conversion between cubic feet and cubic yards is as follows: number of cubic feet x 0.037 = number of cubic yards Excavation Side slopes of excavated areas should be no steeper than 1:1. The maximum depth of excavation within the wet storage area should be 4 feet to facilitate clean-out and for site safety considerations. Outlet The outlet for the sediment trap shall consist of a stone section of the embankment located at the low point in the basin. A combination of coarse aggregate and riprap shall be used to provide for filtering/detention as well as outlet stability. The smaller stone shall be VDOT#3, #357, or#5 Coarse Aggregate (smaller stone sizes will enhance filter efficiency) and riprap shall be "Class I." Filter cloth which meets the physical requirements noted in Std. & Spec. 3.19, RIPRAP shall be placed at the stone-soil interface to act as a"separator." The minimum length of the outlet shall be 6 feet times the number of acres comprising the total area draining to the trap. The crest of the stone outlet must be at least 1.0 foot below the top of the embankment to ensure that the flow will travel over the stone and not the embankment. The outlet shall be configured as noted in Plate 3.13-2. Embankment Cross-Section The maximum height of the sediment trap embankment shall be 5 feet as measured from the base of the stone outlet. Minimum top widths (W) and outlet heights (Ho) for various embankment heights (H) are shown in Plate 3.13-1. Side slopes of the embankment shall be 2:1 or flatter. Removal Sediment traps must be removed after the contributing drainage area is stabilized. Plans should show how the site of the sediment trap is to be graded and stabilized after removal. Construction Specifications 1. The area under the embankment shall be cleared, grubbed, and stripped of any vegetation and root mat. 2. Fill material for the embankment shall be free of roots or other woody vegetation, organic material, large stones, and other objectionable material. The embankment should be compacted in 6-inch layers by traversing with construction equipment. III - 73 1992 3.13 MINIMUM TOP WIDTH (w) REQUIRED FOR SEDIMENT TRAP EMBANKMENTS ACCORDING ORDING TO HEIGHT OF EMBANKMENT (FEE T) W H H0 W i 1.5 0.5 2.0 2.0 1.0 2.0 2.5 1.5 2.5 3.0 2.0 2.5 ti. 3.5 2.5 3.0 Ho H 4.0 3.0 3.0 i 4.5 3.5 4.0 j 5.0 4.0 4.5 I ICI I IiT1Tf-, EXCAVATED AREA MAX. DEPTH = 4' ORIGINAL GROUND ELEV. Source: Va. DSWC Plate 3.13-1 3. The earthen embankment shall be seeded with temporary or permanent vegetation (see Std. & Spec.'s 3.31 and 3.32) immediately after installation. 4. Construction operations shall be carried out in such a manner that erosion and water pollution are minimized. 5. The structure shall be removed and the area stabilized when the upslope drainage area has been stabilized. 6. All cut and fill slopes shall be 2:1 or flatter (except for excavated, wet storage area which may be at a maximum 1:1.grade). III - 74 1992 3.13 Maintenance 1. Sediment shall be removed and the trap restored to its original dimensions when the sediment has accumulated to one half the design volume of the wet storage. Sediment removal from the basin shall be deposited in a suitable area and in such a manner that it will not erode and cause sedimentation problems. 2. Filter stone shall be regularly checked to ensure that filtration performance is maintained. Stone choked with sediment shall be removed and cleaned or replaced. 3. The structure should be checked regularly to ensure that it is structurally sound and has not been damaged by erosion or construction equipment. The height of the stone outlet should be checked to ensure that its center is at least 1 foot below the top of the embankment. III - 75 1992 3.13 TEMPORARY SEDIMENT TRAP 1'I VARIABLE« ORIGINAL I VARIABLE' GROUND ma { ELEV. 4Si.t./ I 67 CU. YD./ACRE <: �EN VARIABLE Egg 67 CU. YD./ACRE lir r 4 MAX. (EXCAVATED) FILTER CLOTH ORIGINAL GROUND ELEV. 4.4 +SEE PLATE 3.13-1 COARSE AGGREGATE CLASS I RIPRAP CROSS SECTION OF OUTLET CLASS I RIPRAP LENGTH (IN FEET) = � !� � 6 X DRAINAGE AREA (IN AC.) �,_- �`— -, - • DIVERSION''� - • DIKE liP z ti.»ma y, s --, # • -- . ," s ir�la�i.� ��� IThi2 // -mow. - \��`- \ 1 COARSE AGGREGATE / �" ��� EXCAVATED / (7.---- FILTER CLOTH /'�-"•••••• AREA - i rr COARSE AGGREGATE SHALL BE VDOT #3, #357 OR #5 OUTLET (PERSPECTIVE VIEW) Source: Va. DSWC Plate 3.13-2 III - 76 1992 3.18 STD & SPEC 3.18 OUTLET PROTECTION OP Definition Structurally lined aprons or other acceptable energy dissipating devices placed at the outlets of pipes or paved channel sections. Purpose To prevent scour at stormwater outlets, to protect the outlet structure, and to minimize the potential for downstream erosion by reducing the velocity and energy of concentrated stormwater flows. Conditions Where Practice Applies Applicable to the outlets of all pipes and engineered channel sections. x •jj ti ^ ''p`&.a*''§ aJ+ih• . ,t ,tF µ v :{ r t •ti ; 3'. ia'7..: v "r_ , 3.„� v" ', ,w 5. ' a, to. *. , � ,+ "` ,.;;�''' :7 d *,-41, -,,q44 y ..,; n x� �' , K •. ., . , „ftfr +.r am ,`'" ,� 0 , ' i �w ,3... • ' ..� '� r, i c "m��om:v `y (1""„,., " 1 4 ,� i 7`p ' ! '�-e� ,f ,,. �Y '^ Y,,o'--'11;, ''� �. .q i $yY a�GH i '�'.• 'N 4,, fir, ds &t, ku,3 , ,,,1 ,:M ,_• f .r f«`F' '' � '1 a'"rC�w�r 1r , *k.,..x +y am✓ , Vol , •,Ar •clue,$ ',.2,rc id,1--"",'der.4.t 5 Ilf:"r."' �` ''\:4. ...` YIfifr. ' r i �, ; ' _...7'. ..11f1-,ter+-w ' .1/ .r._ "'.� r� ,., , w1 K, x ,..-a„ .ygam ,ate ''�9'y 4^ ^w w+ ,A.. r' .5,..- .; 4,-'' -. ».+_` N.7.': .......4,' .. � r ?4 , , g' + i fps ,..° . *. t,(" — , N 4*3 ` • S Y ` _� aO �p „ 14 . Q^— III — 154 1992 3.18 Planning Considerations The outlets of pipes and structurally lined channels are points of critical erosion potential. Stormwater which is transported through man-made conveyance systems at design capacity generally reaches a velocity which exceeds the capacity of the receiving channel or area to resist erosion. To prevent scour at stormwater outlets, a flow transition structure is needed which will absorb the initial impact of the flow and reduce the flow velocity to a level which will not erode the receiving channel or area. The most commonly used device for outlet protection is a structurally lined apron. These aprons are generally lined with riprap,grouted riprap or concrete. They are constructed at a zero grade for a distance which is related to the outlet flow rate and the tailwater level. Criteria for designing such an apron are contained in this practice. Sample problems of outlet protection design are contained in Appendix 3.18-a. Where flow is excessive for the economical use of an apron, excavated stilling basins may be used. Acceptable designs for stilling basins may be found in the following sources: 1. Hydraulic Design of Energy Dissipators for Culverts and Channels, Hydraulic Engineering Circular No. 14, U. S. Department of Transportation, Federal Highway Administration (83). 2. Hydraulic Design of Stilling Basins and Energy Dissipators. Engineering Monograph No. 25, U.S. Department of the Interior - Bureau of Reclamation, (74). Note: Both of the above are available from the U.S. Government Printing Office. Design Criteria The design of structurally lined aprons at the outlets of pipes and paved channel sections applies to the immediate area or reach below the pipe or channel and does not apply to continuous rock linings of channels or streams (See STORMWATER CONVEYANCE CHANNEL, Std. & Spec. 3.17). Notably, pipe or channel outlets at the top of cut slopes or on slopes steeper than 10% should not be protected using just outlet protection as a result of the reconcentration and large velocity of flow encountered as the flow leaves the structural apron. Outlet protection shall be designed according to the following criteria: Pipe Outlets (See Plate 3.18-1) 1. Tailwater depth: The depth of tailwater immediately below the pipe outlet must be determined for the design capacity of the pipe. Manning's Equation may be used to determine tailwater depth(see Chapter 5,Engineering Calculations). If the tailwater depth is less than half the diameter of the outlet pipe, it shall be classified as a III - 155 1992 3.18 Minimum Tailwater Condition. If the tailwater depth is greater than half the pipe diameter, it shall be classified as a Maximum Tailwater Condition. Pipes which outlet onto flat areas with no defined channel may be assumed to have a Minimum Tailwater Condition. Notably, in most cases where post-development stormwater runoff has been concentrated or increased, MS #19 will be satisfied only by outfall into a defined channel. 2. Apron length: The apron length shall be determined from the curves according to the tailwater condition: • Minimum Tailwater - Use Plate 3.18-3. Maximum Tailwater - Use Plate 3.18-4. 3. Apron width: When the pipe discharges directly into a well-defined channel, the apron shall extend across the channel bottom and up the channel banks to an elevation one foot above the maximum tailwater depth or to the top of the bank (whichever is less). • If the pipe discharges onto a flat area with no defined channel, the width of the apron shall be determined as follows: a. The upstream end of the apron, adjacent to the pipe, shall have a width three times the diameter of the outlet pipe. b. For a Minimum Tailwater Condition, the downstream end of the apron shall have a width equal to the pipe diameter plus the length of the apron. c. For a Maximum Tailwater Condition, the downstream end shall have a width equal to the pipe diameter plus 0.4 times the length of the apron. 4. Bottom grade: The apron shall be constructed with no slope along its length (0.0% grade). The invert elevation of the downstream end of the apron shall be equal to the elevation of the invert of the receiving channel. There shall be no overfall at the end of the apron. 5. Side slopes: If the pipe discharges into a well-defined channel, the side slopes of the channel shall not be steeper than 2:1 (horizontal: vertical). 6. Alignment: The apron shall be located so there are not bends in the horizontal alignment. 7. Materials: The apron may be lined with riprap, grouted riprap, concrete, or gabion baskets. The median sized stone for riprap shall be determined from the curves in Appendix 3.18-a (Plates 3.18-3 and 3.18-4) according to the tailwater condition. The gradation, quality and placement of riprap shall conform to Std. & Spec. 3.19, RIPRAP. • l III - 156 1992 3.18 PIPE OUTLET CONDITIONS A A 3d0 ■ t��rir•Po:ti1 Ntraritnij��� . � � 1 PIPE OUTLET TO FLAT ►`e�e ;�i��1iall AREA WITH NO DEFINED PLAN VIEW ����4����� � CHANNEL ria L a a % I— SECTION A-A FILTER CLOTH KEY IN 6"-9"; RECOMMENDED FOR ENTIRE PERIMETER A . A.. 4 i OPVd.I�j41111 3d (MIN.) d PIPE OUTLET TO WELL -.----""sielleVOA, DEFINED CHANNEL PLAN VIEW ,�4;100±4.�� � .•�•�' L a p �`q i •, ���''t.? 0 % C'; �g': SECTION A-A FILTER CLOTH KEY IN 6"-9"; RECOMMENDED FOR ENTIRE PERIMETER NOTES: 1. APRON LINING MAY BE RIPRAP, GROUTED RIPRAP, GABION BASKET, OR CONCRETE. 2. La IS THE LENGTH OF THE RIPRAP APRON AS CALCULATED USING PLATES 3.18-3 AND 3.18-4. 3. d = 1.5 TIMES THE MAXIMUM STONE DIAMETER. BUT NOT LESS THAN 6 INCHES. Source: Va. DSWC Plate 3.18-1 • III - 157 1992 3.18 8. Filter cloth: In all cases, filter cloth shall be placed between the riprap and the underlying soil to prevent soil movement into and through the riprap. The material must meet or exceed the physical properties for filter cloth found in Std. & Spec. 3.19, RIPRAP. See Plate 3.18-1 for orientation details. Paved Channel Outlets (See Plate 3.18-2) 1. The flow velocity at the outlet of paved channels flowing at design capacity must not exceed the permissible velocity of the receiving channel (see Tables 3.18-A and 3.18- B) 2. The end of the paved channel shall merge smoothly with the receiving channel section. There shall be no overfall at the end of the paved section. Where the bottom width of the paved channel is narrower than the bottom width of the receiving channel, a transition section shall be provided The maximum side divergence of the transition shall be 1 in 3F where; F = V where, F = Froude number V = Velocity at beginning of transition (ft./sec.) d = depth of flow at beginning of transition (ft.) g = 32.2 ft./sec.2 3. Bends or curves in the horizontal alignment at the transition are not allowed unless the Froude number (F) is 1.0 or less, or the section is specifically designed for turbulent flow. III - 158 1992 3.18 PAVED CHANNEL OUTLET ` i`!.tio'�*15k A A • PAVED CHANNEL TRANSITION RIPRAP APRON RECEIVING CHANNEL FILTER FABRIC KEY IN 6"—9" RECOMMENDED FOR ENTIRE PERIMETER NOTES: 1. RIPRAP APRON REDUCES THE FLOW VELOCITY BELOW THE PERMISSIBLE VELOCITY OF THE NATURAL RECEIVING CHANNEL. 2. TRANSITION SIDE DIVERGENCE IS 1 IN 3F, WHERE V F = FROUDE NUMBER = J gd , WHERE V = VELOCITY AT THE BEGINING OF THE TRANSITION d = DEPTH OF FLOW AT THE BEGINING OF THE TRANSITION g = 32.2 ft./sec 2. Source: Va. DSWC Plate 3.18-2 III - 159 1992 3.18 TABLE 3.18-A PERMISSIBLE VELOCITIES FOR GRASS-LINED CHANNELS Channel Slope Lining Velocity* (ft./sec.) Bermudagrass 6 Reed canarygrass Tall fescue 0 - 0.5% Kentucky bluegrass 5 Grass-legume mixture 4 Red fescue Redtop Sericea lespedeza Annual lespedeza Small grains Temporary vegetation 2.5 Bermudagrass 5 Reed canarygrass 5 - 10% Tall fescue Kentucky bluegrass 4 Grass-legume mixture 3 Bermudagrass 4 Greater than 10% Reed canarygrass Tall fescue Kentucky bluegrass 3 * For highly erodible soils, decrease permissible velocities by 25%. Source: Soil and Water Conservation Engineering. Schwab. et. al. and American Society of Civil Engineers III - 160 1992 3.18 TABLE 3.18-B? PERMISSIBLE VELOCITIES FOR EARTH LININGS Permissible Velocities Soil Types (ft./sec.) Fine Sand (noncolloidal) 2.5 Sandy Loam (noncolloidal) 2.5 Silt Loam (noncolloidal) 3.0 Ordinary Firm Loam 3.5 Fine Gravel 5.0 Stiff Clay (very colloidal) 5.0 Graded, Loam to Cobbles (noncolloidal) 5.0 Graded, Silt to Cobbles (colloidal) 5.5 Alluvial Silts (noncolloidal) 5.5 Alluvial Silts (colloidal) 5.0 Coarse Gravel (noncolloidal) 6.0 Cobbles and Shingles 5.5 Shales and Hard Plans 6.0 Source: Soil and Water Conservation Engineering, Schwab, et.al. and American Society of Civil Engineers III - 161 1992 3.18 APPENDIX 3.18-a Sample Problems: Outlet Protection Design Example 1 Given: An 18-inch pipe discharges 24 cfs at design capacity onto a grassy slope (no defined channel). Find: The required length, width and median stone size (d50) for a riprap- lined apron. Solution: 1. Since the pipe discharges onto a grassy slope with no defined channel, a Minimum Tailwater Condition may be assumed. 2. From Plate 3.18-3, an apron length (La) of 20 feet and a median stone size (d50) of 0.8 ft. are determined. 3. The upstream apron width equals three times the pipe diameter; 3 x 1.5ft = 4.5ft. 4. The downstream apron width equals the apron length plus the pipe diameter; 20 ft. + 1.5 ft. = 21.5 ft. Example 2 Given: The pipe in example No. 1 discharges into a channel with a triangular cross-section, 2 feet deep and 2:1 side slopes. The channel has a 2% slope and an "n" factor of .045. Find: The required length,width and the median stone size(d50)for a riprap lining. Solution: 1. Determine the tailwater depth using Manning's Equation. Q = 1.49 RZ3 S12 A III - 162 1992 3.18 2 1 24 = 1.49 2d (.02)2 (2d2) .045 2 22+1 where, d = depth of tailwater d = 1.74 ft. * since d is greater than half the pipe diameter, a Maximum Tailwater Condition exists. 2. From Plate 3.18-4, a median stone size (d50) of 0.5 ft. and an apron length (La) of 41 ft. is determined. 3. The entire channel cross-section should be lined since the maximum tailwater depth is within one foot of the top of the channel. • III - 163 • CA 1--, 0 DESIGN OF OUTLET PROTECTION FROM A ROUND PIPE FLOWING FULL ‘.,0 •-i MINIMUM TAILWATER CONDITION (Tw 0.5 DIAMETER) ‘.0 p. . 90 •• ••• I--- - 1-, ---•!---•-! ,•• C4 ...1: . ;. .:::-:!'ii ;;1.• :' -•,,,• 3 o • • - • '!' '•:' ' - /0 80 I: :: :. ' ::,: -;;•;', '': rl • •• • •,•,,1 • 4 • ••-;.- " '' ';-(041/.11, ai 3' - • •,,. ..!...i Li lc, * #, or ,,, • , n Outlet W = Do + La c,r) Pipe 1 iti 1,1 1 -i--4 , : -r-e- • ,'- 0-- ,-1-1- ',,,,,- ,00, , •, . ;.I ! , '.i . i.:,• ; :. ;::.t:•:,111 Diameter, Do \,.3,kee'L i 'ile III!!! !' ti ..i: .::.!!:• !ro•:,11:0,1Virrj.,.. La —.4 I.). 4. • 1 ; • : , r;.! :' ;:' • - *ao, a 3 water < O.5D0 k '''Cce' !ill 1,dEll • 1; ! ; : ; : ;: •;' 1 1:LI').9,1110.110 ''Oi;t/•'" o - • i • ; , •i •••• *do "\. • i; N.\\ , di II i I HOE I 1 I ' ' /Or.1, „ ,,,' I. . • ., ,-."t Id r•".0_. - , .,a, 5Q • - - 'i !I,1 1-1 --t,--777 -i r;'''-d''• P. 1,1.'„'\.: ;'Fi,'• .f:. 04\ 4-— [I- II. !H J IF 1 / I I 1 ' •+14 I I. [ -..1.11 ,li .11411 tIl 1.1 1 . !il ill 1.1 l' i 41 ' 6 ..1 pity F.,./. 4 1• • rl 4 ,„ • I :,; 11 L I jel ,i. A •' !, - . h itl, 11;• ,IMIR I /-, ... 11/1111/11111 k 11 1 li k. .41110 tir I-.i 1 ' I.: jF014 i' :IF [I' ,:I'.li;:iiiiiIglid Agri All L*'1 i;i• ; !' 4 'i i; • A11112114 "'III' -- 1-._- - --!- 1,, 0 1::1,1'..- 1-;:01#011111111r4- :-.., i i. it" • VI 111110 , 1.. 1111111111111_ 1-- LI[4,,j.1,,,L.,„,,,r,;;;;,140,dil .„11 . • , , I •i'i ! i". 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''' .'1 [III , P. ,, ... mumninimpi li riumurgil 1 0_._ 1. 1 1, ,.., ,iii . .7.1-: i • -.• .!II, . •' •b A i A6j141-4 cu 0 riiiiiIIIIIIIIVIIIr ii""'1 • ,-;;. .-. !..i 1 .4 , '01' .1111,111 .i.: .11...0)— n 2 N 11111111111111111111111111111111111111EM Cilif I i[ 11111174 1 i f[I I: I i 1 1 '1-b,.*.t, i: - :- Pro'4.101111107.1.,i'.ri .,•,-) iiiimisirniiiiimiumhuill enomm-.-1 1 1',.11 w 1 111-1 1,1 LI N' '-' .,110Raludzill'or 11111111111111111111i11111111111111111111111 il': dil H Ill..)'q> i'.. dior- -j3..6* -, L-' ,1"Aiii l•-•,,''', 1.u .'67 iiiiIiiilliiiIiiii101111111111111 HI rid Ir. :.:,,i: .., ,v „ 601141.th, : .AldOr- Air. :., •,.;\'°.di.41.'..dil admia..... i Aim ' .4..dilifil ••• •:0•;• 1 Recommended Min. 11111111111011111 • i. --.. I '::\c) ,:-6...4101PPIPM01011.9" :.. \,?.._..il 6._..;i'd iiillehogdiffao . 0/11111.7 • : . ;.I ,, : I ,i.; ,i, :: ,... . .... .,....:i... -0 ' IlliWillid1WPIIIIPP"--Pr. . . - •.. ":' " ' • ' '.''I-: ;' -:' ''" . :- d5o=6. _.0 • t1+7' 111111111"111111010.1 .....,_ ... II :. , . . : . i ...1 I . . . .. . . I - I 1 • CD ,:,' , ':, II'l i!; .1;1 ill' • • ' • : • — • . ' . il:::!..:iii•::' I:;i 1;:, liii III' • i I . I I C./..) 0 .)--, 3 5 10 20 50 100 200 500 1000 63 ;-- Discharge, ft./sec. oo • • • -,_,_ --;___ _ ' •_,_.- CA Vo o ‘.o 01 DESIGN OF OUTLET:PROTECTION FROM A ROUND PIPE FLOWING FULL 120 - - ,- • N MAXIMUM TAILWATER CONDITION ( T - 0.5 DIAMETER) •` 110 �lii Ii' --- .- tt ,-'-HI' . cn 3D° li 1 I i 1 1 1 I 'HI II I f Er I'; I �III• I � : , I • ,i. II:I;ii II I ' I ! I I '41 4'; IIIIII II I ,, 1 1 I 100 I I I. 'I II Outlet i n Pipe ^ 1 • 1 - D0 + 0.4La 4�i IIII I I I ! I Ill 1 •1II flit 9D ..'. , - _-�. I r . rn Diameter, D° I I La +I �l I I} _ _ ` ° . Il11111 i ; p _ �T_ailw_a er _ 0.5D � 30 � I.°� I i r,' 1.. o�,'c,i; �'� ke FL, N+ nu A.0 I t\ nj1'i Hii,:. .. II i q ' '5 I I . V p } l ilill" 11 I 1 IIIII u co, t. o�P 60 IIII ilk I:' , .,iI .1t1,1 . n -1l , I '111 I,ll 7Ir • ,._, r. n a r r I i l µ l..'' tie�A� •i � ir �I II ii _ ���� �II� I ICI Ulrllf ' :� i '.Id d- n I 50 .K 'HLi I ml I r I• 1 ! n,-- . : .� I, iPIl ' � :I i �f Ill I�III--� f 3 --- �� ai l ! i 1' I I I, I_ 30 �. a,° i ,�1 ,l�l I ill l� ,I to I' [I_,;,;•I�'wii: :Al _ — d1iiIi I I o1 1 pr r ., . _ _ - p ,, ... :....: .. t r—T r. I.' . . I v 20 lit --t -1 •I * 1-I l,,.r•. .w i ; • •' 01.f 2 w II, I. Li 1 ; ,' .I.yl. v _ .— -. I, I II, a II, . I _ ._ • rI j' Iiill,:ilIl I I �O I II I ,� go �n 10 �_- 1 L. : .I. I•II ?tu1 > * ,g�' .b� ,0• 'h•• * „ „ D �., �(8 n DJ .; - • a o -I I 711(//, rd Recommended Min._F d1 a — COI;:; ' . u.1LL li II • I. �O 3 5 10 20 50 100 200 500 1000 f,, o`o Discharge, ft3/sec. 1992 3.14 STD & SPEC 3.14 TEMPORARY SEDIMENT BASIN SB Definition A temporary barrier or dam with a controlled stormwater release structure formed by constructing an embankment of compacted soil across a drainageway. Purpose To detain sediment-laden runoff from disturbed areas in"wet"and"dry" storage long enough for the majority of the sediment to settle out. Conditions Where Practice Applies Below disturbed areas where the total contributing drainage area is equal to or greater than three (3) acres. There must be sufficient space and appropriate topography for the construction of a temporary impoundment. These structures are limited to a useful life of 18 months unless they are designed as permanent impoundments. It is recommended that these measures, by virtue of their potential to impound large volumes of water,be designed by a qualified professional. :I�". .`,•FS+">(' -;••f-i ...,£,.'yJ ".,'p'd.^«^'r-4 .dW, U f e'pOW •.-S" V p i 0. (',&.>Y :.4- 2.f^.•3> ..;1.-�.f^Y£t 3�,4 �, ` .C,::.:'�'.� wii't.:.Cn ,. _ y :@ rx�.E�'^ �..yl+-'d?w.v°S:ws..��.'f` w..� .�sa.�x,,:-..........-0 '�&.rw'wl,. -amr,w-«,w'v,�t;-�vw�.',,:i' !:`.`v._..w-..a.a+•:'£ / •: �� �5� ,�., t�- tw'#< �-' "s.s}•i..� � .J `�`' .raw," ..^<yN � .'Sp;'�da�'+:p� ,}''.'..A- �."'1 `i .�.;yl�„., M X-�� 8-;�$a `:'r . 'q".�+i.< 'nr"-'%�i W-a'•C"...". "'•.''.��.:.-, F*°> *tar, ` 'r ✓<« .aa+..«y..„�, <e��-`..�•S1`w`y ft„r..;rY+./.�YR"t`. ^44 x G, ^tI � r :o -4 .L +H : ''io �Kb`o`'> ; R lam .'..yY� r, k ,;g , 2%00 40, .5f:04) NeV III — 77 1992 3.14 Planning Considerations Effectiveness Sediment basins constructed as per this specification are, at best, 60% effective in trapping sediment which flows into them during large storm events (those which cause flow from the outfall pipe) or during periods of minimal vegetative cover at a construction site (28). Therefore, they should be used in conjunction with erosion control practices such as temporary seeding,mulching,diversion dikes,etc.,to reduce the amount of sediment flowing into the basin. The sediment removal efficiency problems noted for previous designs of the TEMPORARY SEDIMENT TRAP (Std. & Spec. 3.13) are also applicable to the sediment basin. In order to contain the majority of sediment which flows to the structure, the basin should have a permanent pool, or wet storage area and a dry storage area which dewaters over time. The volume of the permanent pool (needed to protect against re-suspension of sediment and promote better settling conditions) must be 67 cubic yards per acre of drainage area and the volume of dry storage above the permanent pool (needed to prevent "short-circuiting" of basin during larger storm events) must be an additional 67 cubic yards per acre of drainage area. The total storage volume of the basin at the principal spillway riser crest will therefore be 134 cubic yards per acre of drainage area (28). Sediment basins, along with other perimeter controls which are intended to trap sediment, shall be constructed as a first step in any land disturbing activity and shall be made functional before upslope land disturbance takes place (MS #4). Location To improve the effectiveness of the basin, it should be located so as to intercept the largest possible amount of runoff from the disturbed area. The best locations are generally low areas and natural drainageways below disturbed areas. Drainage into the basin can be improved by the use of diversion dikes and ditches. The basin must not be located in a live stream but should be located to trap sediment-laden runoff before it enters a stream. The basin should not be located where its failure would result in the loss of life or interruption of the use or service of public utilities or roads. Multiple Use • Sediment basins may remain in place after construction and final site stabilization are completed to serve as permanent stormwater management structures. Because the most practical location for a sediment basin is often the most practical location for a stormwater management basin,it is often desirable to utilize these structures for permanent stormwater management purposes. It should be noted, however,that in most cases, a typical structure's outfall system will vary during the construction and post-construction periods. Care must be taken to avoid constructing an outfall system which will achieve the desired post- construction quantity or quality control but will not provide the necessary medium for the III - 78 1992 3.14 containment and settling of sediment-laden construction runoff. Notably, the design for permanent ponds is beyond the scope of these standards and specifications. Design Criteria Maximum Drainage Area The maximum allowable drainage area into a temporary sediment basin shall be 100 acres. It is recommended that when the drainage area to any one temporary basin exceeds 50 acres, an alternative design procedure which more accurately defines the specific hydrology and hydraulics of the site and the control measure be used. The design procedures in this standard and specification do not generate hydrographs, utilize storage volumes or provide a routing of the design storms; for a large drainage area, this may result in an excessively large diameter riser or an oversized basin. Notably, design considerations which are more accurate and project-specific than those in this specification are acceptable and encouraged with any size basin. Basin Capacity The design storage capacity of the basin must be at least 134 cubic yards per acre of total • contributing drainage area (see Plate 3.14-1). One half of the design volume (or 67 cubic yards) shall be in the form of a permanent pool, and the remaining half as drawdown volume. The volume of the permanent pool shall be measured from the low point of the _ basin to the elevation corresponding to one half the total storage volume. The volume of the drawdown area shall be measured from the elevation of the permanent pool to the crest of the principal spillway (riser pipe). Sediment should be removed from the basin when the volume of the permanent pool has been reduced by one half. In no case shall the sediment cleanout level be higher than one foot below the bottom of the dewatering device. The elevation of the sediment cleanout level should be calculated and clearly marked on the plans and riser (since this part of the riser normally will be under water, a mark should appear above the permanent pool a measured distance above the cleanout elevation). While attempting to attain the desired storage capacities, efforts should be made to keep embankment heights to a minimum. This precaution takes on added significance when the basin will only serve as a temporary measure or will need substantial retrofitting prior to functioning as a permanent measure. When site topography permits, the designer should give strong consideration to the use of excavation to obtain the required capacity and to possibly reduce the height of the embankment. This excavation can be performed in a manner which creates a wet storage forebay area or which increases the storage capacity over the entire length of the basin. Basin Shape To improve sediment trapping efficiency of the basin,the effective flow length must be twice the effective flow width. This basin shape may be attained by properly selecting the site of III - 79 1992 3.14 the basin, by excavation, or by the use of baffles. See Appendix 3.14-a for pertinent design details. MINIMUM STORAGE VOLUME AND SEDIMENT S T ORA. GE 67 C.Y./ AO."DRY"STORAGE ... .. DEWATERING 111[ DEVICE " WET .. STORAGE _ 'si'vxeioiei":e;ieieiaNSI 27410 : . ....._...-arainumanail SEDIMENT CLEANOUT POINT (" WET " STORAGE REDUCED TO 34 C.Y./ ACRE) Source: Va. DSWC Plate 3.14-1 Embankment Cross-Section For embankments of less than 10 feet, the embankment must have a minimum top width of 6 feet, and the side slopes must be 2:1 or flatter. In the case of an embankment 10 to 14 feet in height, the minimum top width shall be 8 feet and the side slopes shall be 2 2:1 or flatter. For 15-foot embankments (maximum allowed under these specifications), the top width must be 10 feet with maximum 2 2:1 side slopes. Spillway Design The outlets for the basin shall consist of a combination of principal and emergency spillways. These outlets must pass the peak runoff expected from the contributing drainage area for a 25-year storm. If, due to site conditions and basin geometry, a separate emergency spillway is not feasible,the principal spillway must pass the entire peak runoff expected from the 25-year storm. However, an attempt to provide a separate emergency spillway should always be made (refer to "Emergency Spillway" later on in this section). Runoff computations shall be based upon the soil cover conditions which are expected to prevail III - 80 1992 3.14 during the life of the basin. Refer to Chapter 5 for calculation of the peak rate of runoff. Notably, the flow through the dewatering orifice cannot be utilized when calculating the 25- year storm elevation because of its potential to become clogged;therefore,available spillway storage must begin at the principal spillway riser crest. The spillways designed by the procedures contained in the standard and specification will not necessarily result in any reduction in the peak rate of runoff. If a reduction in peak runoff is desired,the appropriate hydrographs/storm routings should be generated to choose the basin and outlet sizes. Principal Spillway For maximum effectiveness, the principal spillway should consist of a vertical pipe or box of corrugated metal or reinforced concrete, with a minimum diameter of 15 inches,joined by a watertight connection to a horizontal pipe (barrel) extending through the embankment and outletting beyond the downstream toe of the fill. If the principal spillway is used in conjunction with a separate emergency spillway, the principal spillway must be designed to pass at least the peak flow expected from of 2-year storm. If no emergency spillway is used, the principal spillway must be designed to pass the entire peak flow expected from a 25-year storm (see Appendix 3.14-a for design details). Design Elevations The crest of the principal spillway shall be set at the elevation corresponding to the storage volume required (67 cubic yards/acre wet storage plus 67 cubic yards/acre dry storage = 134 cubic yards/acre). If the principal spillway is used in conjunction with an emergency spillway, this elevation shall be a minimum of 1.0 foot below the crest of the emergency spillway. In addition; a minimum freeboard of 1.0 foot shall be provided between the design high water (25-year) and the top of the embankment (see Plate 3.14-2). If no emergency spillway is used, the crest of the principal spillway shall be a minimum of 3 feet below the top of the embankment; also, a minimum freeboard of 2.0 feet shall be provided between the design high water and the top of the embankment. Anti-Vortex Device and Trash Rack An anti-vortex device and trash rack shall be attached to the top of the principal spillway to improve the flow characteristics of water into the spillway and prevent floating debris from blocking the principal spillway. The anti-vortex device shall be of the concentric type as shown in Plate 3.14-10. See Appendix 3.14-a for design procedures for the anti-vortex device and trash rack. Dewatering Provisions shall be made to dewater the basin down to the permanent pool elevation. Recent studies by the Washington Metropolitan Council of Governments have shown that III - 81 1992 3.14 it is necessary to provide at least a 6-hour drawdown time in the dry storage area in order to achieve up to 60% removal of sediment (28). Dewatering of the dry storage should be done in a manner which removes the "cleaner" water without removing the potentially sediment-laden water found in the wet storage area or any appreciable quantities of floating debris. An economical and efficient device for performing the drawdown is a section of perforated vertical tubing which is connected to the principal spillway at two locations. See Plate 3.14-15 which depicts the orientation of such a device. By virtue of the potential for the dewatering device or orifice becoming clogged, no credit is given for drawdown by the device in the calculation of the principal or emergency spillway locations. The method for sizing the dewatering orifice and the associated flexible conduit is located in Appendix 3.14-a. Base The base of the principal spillway must be firmly anchored to prevent its floating. If the riser of the spillway is greater than 10 feet in height, computations must be made to determine the anchoring requirements. A minimum factor of safety of 1.25 shall be used (downward forces = 1.25 x upward forces). For risers 10 feet or less in height, the anchoring may be done in one of the two following ways: 1. A concrete base 18 inches thick and twice the width of riser diameter shall be used and the riser embedded 6 inches into the concrete. See Plate 3.14-3 and Appendix 3.14-a for design details. 2. A square steel plate, a minimum of 1/4-inch thick and having a width equal to twice the diameter of the riser shall be used; it shall be covered with 2.5 feet of stone, gravel, or compacted soil to prevent flotation. See Plate 3.14-3 and Appendix 3.14-a for design details. Note: If the steel base is used, special attention should be given to compaction so that 95% compaction is achieved over the plate. Also, added precautions should be taken to ensure that material over the plate is not removed accidently during removal of sediment from basin. Barrel The barrel of the principal spillway, which extends through the embankment, shall be designed to carry the flow provided by the riser of the principal spillway with the water level at the crest of the emergency spillway. The connection between the riser and the barrel must be watertight. The outlet of the barrel must be protected to prevent erosion or scour of downstream area. See Appendix 3.14-a for design details. III - 82 1992 3.14 1 SEDIMENT BASIN S CHEMA TI C ELE VA.TIO.NS ' CREST OF EMERGENCY SPILLWAY DESIGN HIGH WATER _____L (25—YR. STORM ELEV.) T MIN. 1.0' 0.5' t MIN. 1.0' \ RISER CREST 67 C ./ AC. DEWATERING " DRY " STORAGE DEVICE 67 C.Y./ AC. :•:::::::•:: ::: " WET " STORAGE . s••"' :f4 WA SEDIMENT CLEANOUT POINT T.- (" WET " STORAGE REDUCED TO 34 C.Y./ ACRE) DESIGN ELEVATIONS WITH EMERGENCY SPILLWAY • DESIGN HIGH WATER : (25—YR. STORM ELEV.) MIN.l2.0 v t T MIN. 3.0' 0.5' MIN. 1.0' i 67 C.Y./ AC. rfr•........'.'.' " DRY " STORAGE --�I :::.:...::................... . RISER CREST 67 C.Y./ AC. :::::1►:::::•::•::• •:.:.:::•::• " WET " STORAGE DEWATERING ::: • . .. .::::r DEVICE TIM ire.Pri 't `fir ii "sos€a SEDIMENT CLEANOUT POINT �1.'. DESIGN ELEVATIONS WITHOUT EMERGENCY SPILLWAY (RISER PASSES 25—YR. EVENT) Source: Va. DSWC Plate 3.14-2 III - 83 • 1992 3.14 RISER PIPE BASE CONDITIONS III—�I pr s" =111111 = IH1 —I -11L-11�111= ,s 3o I I�III. TI�' AII I I 11= I _ ___ II —I �I�III�i I —II I—IIIT I I H — i t ,� I ,tl I I I II— I rf=1T1I I TYPICAL CONCRETE BASE TYPICAL STEEL BASE Source: Va. DSWC Plate 3.14-3 Anti-Seep Collars Anti-seep collars shall be used on the barrel of the principal spillway within the normal saturation zone of the embankment to increase the seepage length by at least 10%, if either of the following two conditions is met: 1. The settled height of the embankment exceeds 10 feet. 2. The embankment has a low silt-clay content (Unified Soil Classes SM or GM) and the barrel is greater than 10 inches in diameter. The anti-seep collars shall be installed within the saturated zone. The maximum spacing between collars shall be 14 times the projection of the collars above the barrel. Collars shall not be closer than 2 feet to a pipe joint. Collars should be placed sufficiently far apart to allow space for hauling and compacting equipment. Precautions should be taken to ensure that 95% compaction is achieved around the collars. Connections between the collars and the barrel shall be watertight. See Plate 3.14-4 and Appendix 3.14-a for details and design procedure. III - 84 1992 3.14 } ANTI-SEEP COLLAR " T*� SATURATED ZONE CONNECTIONS BETWEEN :.:f•:: , THE ANTI-SEEP AND THE BARREL MUST B ::•:::.:.� :.;.: . ................................................... WATERTIGHT ,:.�::P::r: ::;"�;:���;:`.t;::;;>:'•:?:??:t�4irP: : :��:;�::;::•:.......... .. .......... ............................................................................ ............................ ........ .: -1 11 I.� 1711.10:44. " — 1=■-:u.:,._ : s <:::. 1 I.—I_ 11 ILA =11. 11 III —1.=11.= — I .Il►— o —I —C= =11.=1i=11.=11.=1L-�IL 11—' o_ ' II _ 11=11- = ET ��- 11 I =11. _.u=u. Source: Va. DSWC Plate 3.14-4 Alternatives to Anti-Seep Collars Anti-seep collars are designed to control seepage and piping along the barrel by increasing the flow length and thus making any flow along the barrel travel a longer distance. However, due to the constraints that collars impose on embankment fill placement and compaction,collars may sometimes be ineffective or actually result in an increase in seepage and piping. Alternative measures have been developed and are being incorporated into embankment designs. These measures include a structure known as a "filter diaphragm." A filter diaphragm consists of a layer of sand and fine gravel which runs through the dam embankment perpendicular to the barrel. Typically, the structure is 4 to 5 inches in width, approximately one foot in height and is located at the barrel elevation at its intersection with the upper bounds of the seepage zone. The measure controls the transport of embankment fines, which is the major concern with piping and seepage. The diaphragm channels any undesirable flow through the fine-graded material, which traps any embankment material being transported. The flow is then conveyed out of the embankment through a perforated toe drain. The critical design element of the filter diaphragm is the grain-size distribution of the filter material which is determine.d by the grain-size distribution of the embankment fill material. The use and design of these measures should be based on site-specific geotechnical information and should be supervised by a qualified professional. • III - 85 1992 3.14 Emergency Spillway The emergency spillway acts as a safety release for a sediment basin, or any impoundment- type structure, by conveying the larger, less frequent storms through the basin without damage to the embankment. The emergency spillway also acts as its name implies - in case of an emergency such as excessive sedimentation or damage to the riser which prevents flow through the principal spillway. The emergency spillway shall consist of an open channel (earthen and vegetated) constructed adjacent to the embankment over undisturbed material (not fill). Where conditions will not allow the construction of an emergency spillway on undisturbed material, a spillway may be constructed of a non-erodible material such as riprap. The spillway shall have a control section at least 20 feet in length. The control section is a level portion of the spillway channel at the highest elevation in the channel. See Plate 3.14-5 and Appendix 3.14-a for details and design procedure. An evaluation of site and downstream conditions must be made to determine the feasibility and justification for the incorporation of an emergency spillway. In some cases, the site topography does not allow a spillway to be constructed in undisturbed material, and the temporary nature of the facility may not warrant the cost of disturbing more acreage to construct and armor a spillway. The principal spillway should then be sized to convey all the design storms. If the facility is designed as a permanent facility with downstream restrictions, the added expense of constructing and armoring an emergency spillway may be justified. Capacity The emergency spillway shall be designed to carry the portion of the peak rate of runoff expected from a 25-year storm which is not carried by the principal spillway. See Appendix 3.14-a for design procedure and details. Design Elevations The 25-year storm elevation through the emergency spillway shall be at least 1.0 foot below the top of the embankment. The crest of the emergency spillway channel shall be at least 1.0 foot above the crest of the principal spillway. Location The emergency spillway channel shall be located so that it will not be constructed over fill material. The channel shall be located so as to avoid sharp turns or bends. The channel shall return the flow of water to a defined channel downstream from the embankment. Maximum Velocities The maximum allowable velocity in the emergency spillway channel will depend upon the type of lining used. For vegetated linings, allowable velocities are listed in Table 3.17-A (Std. & Spec. 3.17, STORMWATER CONVEYANCE CHANNELS). For non-erodible III - 86 1992 3.14 linings, such zs concrete or riprap, design velocities may be increased. However, the emergency spillway channel shall return the flow to the receiving channel at anon-eroding velocity. See Appendix 3.14-a for design procedure and details. EMERGENCY SPILL WA Y CONTROL SECTION EMERGENCY SPILLWAY SHOULD NOT BE CONSTRUCTED OVER FlLL MATERIALFF- - -"*,:::tall:111:111.1.1.1461..,.::::.:11.1titai: j & Source: Va. DSWC Plate 3.14-5 Stabilization The embankment of the sediment basin shall receive temporary or permanent seeding immediately after installation (see TEMPORARY SEEDING, Std. & Spec. 3.31 or • PERMANENT SEEDING, Std. & Spec. 3.32). If excavation is required in the basin, side slopes should not be steeper than 1 Z:1. Disposal Sediment shall be removed from the basin when the sediment level is no higher than 1 foot below the bottom of the dewatering orifice, or one-half of the permanent pool volume, whichever is lower. Plans for the sediment basin shall indicate the methods for disposing III - 87 1992 3.14 of sediment removed from the basin. Possible alternatives are the use of the material in fill areas on-site or removal to an approved off-site location. Sediment basin plans shall indicate the final disposition of the sediment basin after the upstream drainage area is stabilized. The plans shall include methods for the removal of excess water lying over the sediment, stabilization of the basin site, and the disposal of any excess material. Where the sediment basin has been designed as a permanent stormwater management basin, plans should also address the steps necessary for the conversion from sediment basin to a permanent detention or retention facility. Safety Sediment basins can be attractive to children and can be dangerous. They should, therefore, be fenced or otherwise made inaccessible to persons or animals unless this is deemed unnecessary by the plan approving authority due to the remoteness of the site or other circumstances. Strategically placed signs around the impoundment reading "DANGER- QUICKSAND" should also be installed. In any case, local ordinances and regulations regarding health and safety must be adhered to (see Std. & Spec. 3.01, SAFETY FENCE). Construction Specifications Site Preparation Areas under the embankment or any structural works related to the basin shall be cleared, grubbed, and stripped of topsoil to remove trees, vegetation, roots, or other objectionable material. In order to facilitate cleanout and restoration, the area of most frequent inundation(measured from the top of the principal spillway)will be cleared of all brush and trees. Cutoff Trench For earth-fill embankments, a cutoff trench shall be excavated along the centerline of the dam. The trench must extend at least 1 foot into a stable, impervious layer of soil and have a minimum depth of 2 feet. The cutoff trench shall extend up both abutments to the riser crest elevation. The minimum bottom width shall be 4 feet, but also must be wide enough to permit operation of compaction equipment. The side slopes shall be no steeper than 1:1. Compaction requirements shall be the same as those for the embankment. The trench shall be drained during the backfilling/compacting operations. Embankment The fill material shall be taken from approved borrow areas. It shall be clean mineral soil, free of roots,woody vegetation, stumps, sod, oversized stones, rocks, or other perishable or objectionable material. The material selected must have enough strength for the dam to III - 88 1992 3.14 remain stable and be tight enough, when properly compacted, to prevent excessive percolation of water through the dam. Fill containing particles ranging from small gravel or coarse sand to fine sand and clay in desired proportion is appropriate. Any embankment material should contain approximately 20% clay particles by weight. Using the Unified Soil Classification System, SC (clayey sand), GC (clayey gravel) and CL ("low liquid limit" clay) are among the preferred types of embankment soils. Areas on which fill is to be placed shall be scarified prior to placement of fill. The fill material should contain the proper amount of moisture to ensure that 95% compaction will be achieved. Fill material will be placed in 6-inch continuous layers over the entire length of the fill. Compaction shall be obtained by routing the hauling equipment over the fill so that the entire surface of the fill is transversed by at least one wheel or tread track of the equipment, or by using a compactor. Special care shall be taken in compacting around the anti-seep collars (compact by hand, if necessary) to avoid damage and achieve desired compaction. The embankment shall be constructed to an elevation 10% higher than the design height to allow for settlement if compaction is obtained with hauling equipment. If compactors are used for compaction, the overbuild may be reduced to not less than 5%. Principal Spillway The riser of the principal spillway shall be securely attached to the barrel by a watertight connection. The barrel and riser shall be placed on a firmly compacted soil foundation. The base of the riser shall be firmly anchored according to design criteria to prevent its floating. Pervious materials such as sand, gravel, or crushed stone shall not be used as backfill around the barrel or anti-seep collars. Special care shall be taken in compacting around the anti-seep collars (compact by hand, if necessary). Fill material shall be placed around the pipe in 4-inch layers and compacted until 95% compaction is achieved. A minimum of two feet of fill shall be hand-compacted over the barrel before crossing it with construction equipment. Emergency Spillway Vegetative emergency spillways shall not be constructed over fill material. Design elevations, widths, entrance and exit channel slopes are critical to the successful operation of the spillway and should be adhered to closely during construction. Vegetative Stabilization The embankment and emergency spillway of the sediment basin shall be stabilized with temporary or permanent vegetation immediately after installation of the basin (see TEMPORARY SEEDING, Std. & Spec. 3.31 or PERMANENT SEEDING, Std. & Spec. 3.32). Erosion and Sediment Control The construction of the sediment basin shall be carried out in a manner such that it does not result in sediment problems downstream. III - 89 1992 3.14 Safe All state and local requirements shall be met concerning fencing and signs warning the public of the hazards of soft, saturated sediment and flood waters (refer to Std. & Spec. 3.01, SAFETY FENCE). Maintenance The basin embankment should be checked regularly to ensure that it is structurally sound and has not been damaged by erosion or construction equipment. The emergency spillway should be checked regularly to ensure that its lining is well established and erosion-resistant. The basin should be checked after each runoff-producing rainfall for sediment cleanout. When the sediment reaches the clean-out level, it shall be removed and properly disposed of. III - 90 1992 3.14 APPENDIX 3.14-a Design Procedure for Temporary Sediment Basins The following design procedure provides a step-by-step method for the design of a temporary sediment basin. The data sheet found in the back of this Appendix should be used in the erosion and sediment control plan to outline design values calculated. Basin Volume A. Determine the required basin volume. The design capacity of the basin must be at least 134 cubic yards per acre of total contributing drainage area, half of which shall be in the form of a permanent pool or wet storage, and the remaining half as a "drawdown" area or dry storage. 1. For a natural basin, the wet storage volume may be approximated as follows: Vl = 0.4 x Al x Dl where, Vl = the wet storage volume in cubic feet Ai = the surface area of the flooded area at the invert of the dewatering outlet, in square feet Di = the maximum depth in feet, measured from the low point in the basin to the invert of the • dewatering outlet 2. For a natural basin, the dry storage volume may be approximated as follows: V = Ai + A2 x D 2 2 2 where, V2 = the dry storage volume in cubic feet Al = the surface area of the flooded area at the invert of the dewatering outlet, in square feet (see #1 above) A2 = the surface area of the flooded area at the crest of the principal spillway III - 91 1992 3.14 D2 = the depth, in feet, measured from the invert of the dewatering outlet to the crest of the principal spillway Note 1: The volumes may be computed from more precise contour information or other suitable methods. Note 2: Conversion between cubic feet and cubic yards is as follows: number of cubic feet x 0.037 = number of cubic yards B. If the volume of the basin is inadequate or embankment height becomes excessive, pursue the use of excavation to obtain the required volume. II. Basin Shape A. The shape of the basin must be such that the length-to-width ratio is at least 2 to 1 according to the following equation: Length-to-width Ratio = We where, • We = A/L = the effective width A = the surface area of the normal pool L = the length of the flow path from the inflow to the outflow. If there is more than one inflow point, any inflow which carries more than 30% of the peak rate of inflow must meet these criteria. B. The correct basin shape can be obtained by proper site selection, excavation, or the use of baffles. Baffles increase the flow length by deflecting the flow. The baffles should be placed halfway between the inflow point and the outflow. Plate 3.14-6 shows the detail for baffle construction and three situations where baffles might be used. III. Determine whether the basin will have a separate emergency spillway. III - 92 1992 3.14 IV. Determine the elevation of the crest of the principal spillway for the required volume (dewatering orifice at 67 cubic yards per acre and crest of principal spillway 134 cubic yards per acre). V. Estimate the elevation of the design high water and the required height of the dam. A. If an emergency spillway is included, the crest of the principal spillway must be at least 1.0 foot below the crest of the emergency spillway. B. If an emergency spillway is included, the elevation of the peak flow through the emergency spillway (which will be the design high water for the 25-year storm) must be at least 1.0 foot below the top of embankment. C. If an emergency spillway is not included, the crest of the principal spillway must be at least 3 feet below the top of the embankment. D. If an emergency spillway is not included, the elevation of the design high water for the 25-year storm must be 2.0 feet below the top of the embankment. VI. Using Chapter 5 of this handbook, determine the peak rate of runoff expected from the drainage area of the basin for a 25-year storm. The "C" factor or "CN" value used in the runoff calculations should be derived from analysis of the contributing .- drainage area at the peak of land disturbance (condition which will create greatest peak runoff). VII. Principal Spillway Design A. If an emergency spillway is included, the principal spillway must at least pass the peak rate of runoff from the basin drainage area for a 2-year storm. 1. Qp = the 2-year peak rate of runoff. B. If an emergency spillway is not included, the principal spillway must pass the peak rate of runoff from the basin drainage area for a 25-year storm. 1. Therefore, Qp = the 25-year peak rate of runoff. • III - 93 1992 3.14 EXAMPLE PLAN VIEWS OF BAFFLE L 0 CA TIONS IN SEDIMENT BASINS D L: -I D/2 1.1 NO SCALE INFLOW y---. � ' �T,„ • RISER `- F D/2 010. NORMAL POOL \� L = TOTAL DISTANCE FROM THE POINT OF INFLOW AROUND THE BAFFLE TO THE RISER. I NORMAL POOL \� 0/2 L ! )` RISER - ..-____ +r J NORMAL POOL RISER INFLOW s —� c BAFFLE , \ R �, 0 i��\ --- L N ', D//2 \ 1 N. , L2 ` L - L1 + L2 INFLOW SHEETS OF 4' X 8' X 1/2' EXTERIOR 6" PLYWOOD OR EQUIVALENT r -r n , n r RISER CREST ELEVATION 4' -wit POSTS MIN. SIZE 4 SQUARE 1 OR 5 ROUND. SET AT i LJ _ 8r 0.-I] r LEAST 3' INTO THE GROUND. Source: USDA-SCS Plate 3.14-6 III - 94 1992 3.14 C. Refer to Plate 3.14-7, where h is the difference between the elevation of the crest of the principal spillway and the elevation of the crest of the emergency spillway. D. Enter Plate 3.14-8 with Q P. Choose the smallest riser which will pass the required flow with the available head, h. E. Refer to Plate 3.14-7, where H is the difference in elevation of the centerline of the outlet of the barrel and the crest of the emergency spillway. L is the length of the barrel through the embankment. F. Enter Table 3.14-A or Table 3.14-B with H. Choose the smallest size barrel which will pass the flow provided by the riser. If L is other than 70 feet, make the necessary correction. VIII. Emergency Spillway Design A. The emergency spillway must pass the remainder of the 25-year peak rate of runoff not carried by the principal spillway. B. Compute, Qe = 025 - Qp C. Refer to Plate 3.14-9 and Table 3.14-C. D. Determine approximate permissible values for b, the bottom width; s, the slope of the exit channel; and X, minimum length of the exit channel. E. Enter Table 3.14-C and choose an exit channel cross-section which passes the required flow and meets the other constraints of the site. F. Note: 1. The maximum permissible velocity for vegetated waterways must be considered when designing an exit channel. 2. For a given Hp, a decrease in the exit slope from S as given in the table decreases spillway discharge, but increasing the exit slope from S does not increase discharge. If an exit slope (Se) steeper than S is used, then design procedures found in "Open Channel Flow" in Chapter 5 should be used to verify the adequacy of the exit channel. 3. Data to the right of heavy vertical lines should be used with caution, as the resulting sections will be either poorly proportioned or have excessive velocities. • III - 95 1992 3.14 PRINCIPAL SPILL WA Y DESIGN EMERGENCY SPILLWAY CREST DESIGN HIGH WATER J♦h t r 1 ANTI-VORTEX ANTI-SEEP DEVICE t Dr.••+r- COLLARS RISER BARREL VITT � r-in-DP =1L=1L—.11.=1'=�==11=1��1"tL�, ,. ..` IC=IL.Il`'71: . .IL=.u.=,�.-; _L'=11 IL=1� ?I1�1� 1=11.- m11=1�--I1r-11.=11„ • o mit=2=11.==11 I=1= = :I— _ T('=1 JI. IL= — — CONCRETE BASE N=1-11:IL J-u=11— - - H = HEAD ON PIPE THROUGH EMBANKMENT h = HEAD OVER RISER CREST L = LENGTH OF PIPE THROUGH EMBANKMENT DP- DIAMETER OF PIPE THROUGH EMBANKMENT Dr = DIAMETER OF RISER } Source: Va. DSWC Plate 3.14-7 • III - 96 • 1992 3.14 fl00 r _ 4 , Riser Inflow Curves t ............_.......__....._...:.._......v.._..... . . ..- .--,_ . 1 f i � 6001- - f _ 1' LegendI..-..._.............q..._........._�.-:......... ......... .. .!Or- rrr ) Weir flow. Qw=9,139 DrH3/2 ' • Orifice flow, Qo=3J82 D2H —"_.__.._. � t•. ,• ''` a : i y i � F i ! i 200E __ ...... —t ....4 r j / �iJ t i t { : } J I : • i r• t ,11 .. tT11 i : ( .� f• • `` i S 1 - : .r _ t ! r! ......:.... 1 i f-r � j I. , . , , • i I',44 • ' i 1 i 1 1 1 t t. s t ! )ç1r • Y • }} 30 p__... . . . 1 s o i . . i . I... .. .d :j' .... .. :f::I_. • ; 1 E :.... t ; .. ;r j .. .. ...... _ ... ..i..._. .... . ...:. kk 1 1 .:..._... .. { 1 ! {. ♦.....-n.'.. ...i.. ._s........€...._.... 1. I .-- • 7 �•�.{,., • i .•i1• .. 1 y i,, 1 I . _: . , / ... : , t, ,... : .4.4..... 6 it-- • 1 i — t ` 7 E .. . ...i s ` f 41 elk) I ill ' _1 —_r i is 1 ! i 1 i I . . r.. ; ....e_...,. :._.• • t ,., .: E .P..:.... ..:.. .:... :i.i.. ..... .............: .. ............. i J , "i .i i i. 0.1 0.2 03 0.4 0.5 0.6 0.8 ID 2.0 3.0 4.05.0 6.0 8.0 100 Head in feet, measured from crest of riser • Source: USDA-SCS Plate 3.14-8 III - 97 68' 68' 88' L8' Z6' S8' V8' E8' 28' 08' 6L' LL' SL' VG' EL' IL' 0/_' 69' 69' 89' 09T 06' 16' T6' 06' 68' 98' 88' L8' 98' S8' V8' Z8' 19' 6L' 8L' LL' 9L' SL' VC' EL' ZL' 04T Z6' 46' C6' C6' Z6' 68' T6' 06' 68' 68' L8' 96' G8' E8' E8' Z8' T8' 06' 6L' 6L' 8L' 0ZT V6' 96' 96' 56' S6' 56' V6' 66' E6' C6' Z6' T6' 06' 68' 68' 88' L8' 98' 98' G8' S8' 00T V6' L6' L6' L6' L6' 96' 96' 96' S6' G6' V6' 46' E6' Z6' Z6' T6' T6' 06' 06' 69' 69' 06 66' 66' 66' 86' 86' 86' 86' 86' 86' L6' L6' L6' 96' 96' 96' 56' 56' 56' S6' 76' b6' 08 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00°T 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00'T 00'1 00'T 0L T°'T ZO'T ZO'T ZO'T ZO'T ZO'T ZO'T ZO'T E0'T E0'i E0'1 60'T 40'T 50'T 50'T SO'I 90'I 90'T LO'T LO'T LO'T 09 EO'T EO'I E0't 40'i VO'I VO'i 50'T 50'T 90'T 90'T LO'T 80'T 60'T DI'I IT-T Cr! 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C/) £I0'0 = u `L IVHD MO7,4 HdId g-bi'£ a'IfVZ 1992 3.14 TABLE 3.14-C • DESIGN DATA FOR EARTH SPILLWAYS STAGE SFILIWAY BOTTOM WIDTH (b)IN FEET (Hp) ET VARIABLES 8 10 12 IN FEET 14 16 18 20 22 24 26 28' 30 32 34 36 38 40 0 6 7 8 10 II 13 14 15 17 18 20 21 22 24 25 27 28 C S V 2.7 2.7 2.7 2.7 2.7 ' 2 7 2.7 2 71 2.7 2.7 2.7 2.7 2.7 2 7 2 7 2.7 2.7 S 39 3.9 3.9 3.9 3 8 3.8 3.8 3.8 3.8 3.8 3.8 3.8 3.8 3.8 3.9 3.8 3.8 X 32 ' 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 33 O B 10 1'2 14 ' I 18 20 22 24 26 28 30 32 34 35 37 39 0.6 V 30 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 30 3.0 3.0 3.0 3.0 3.0 3.0 3.0 S 3.7 3.7 3.7 3.7 3 6 3.7 3.6 3.6 3.6 3.6 3 6 3.6 3.6 3.6 3.6 3.6 3.6 ' X 36 36 36 36 36 36 37 37 37 37 37 37 37 37 37 37 37 0 II 13 16 18 20 23 25 28 30 33 35 38 _ 41 43 44 46 48 0 7 V 3.2 3.2 3.3 3.3 3.3 3.3 3.3_ 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 S 3.5 3.5 3.4 3.4 3,4 5.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 X 39 40 40 40 41 41 41 41 41 41 41 41 41 41 41 41 41 - O 13 16 19 22 26 29 32 35 38 42 45 46 48 51 54 57 60 0.8 V 3.5 3.5 3.5 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 S 3.3 3.3 3.3 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2 3.2, 3.2 X 44 44 44 44 45 45 45 45 45 45 45 45 45 45 45 45 45 O 17 20 24 28 32 35 39 43 47 51 53 • 57 60 64 68 71 75 09 V 3.7 3.8 3.8 3.8 3.6 3.8 3.8 38 3.8 3.8 3.8 3.8 3.8 3.8 3.8 38 3.8 S 3.2 3.'1 3.1 3.1 3.1 3.1 3.1, 3.1 3 1 3.1 3 1 3.1 3.1 3.1 3.1 3.1 3.1 X 47 47 48 48 48 r 48 48 48 48 48 49 49 49 49 49 49 ' 49 O 20 24 29 33 38 42 47 51 56 61 63 68 72 77 81 86 90 I.0 V 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4,0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 S 3.1 3.0 3.0 3.0 3.0 3.5 3.0 3.0 3.0 3.0 3.0 3 0 3.0 3.0 3.0 3,0 3.0 X 51 51 5 I 5 I 52 52 52 52 52 52 52 52 52 52 52 52 52 O 23 28 34 39 44 49 54 60 _65 70 74 79 84 89 95 100 105 I.I V 42 42 42 4.3 4.3 4.3 4.3 4.3 4.3 43 4.3 4.3 4.3 4.3 4.3 4.3 4.3 S 2.9 2.9 2.9 2.9 2.9 2.9 2.9 2.9 2.9 2.8 2.8 2.8 2.9 2.8 2.8 2.8 2.8 X 55 55 5 5 5 5 55 55 55 56 56 56 5 6 56 56 56 56 56 56 O 28 33 40 45 51 58 64 69 76 80 86 92 98 104 110 116 122 2 V 4.4 4.4 4.4 44 4.4 45 45 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 4.5 S 2.9 2 9 2.8 2 8 2.8 2.8 2 8 2 8 2.8 28 2.8 2.8 2.8 2.8 2 8 2.8 2.8 X 58 58 59 59 59 59 59 59 60 60 60 60 60 60 60 60 60 O 32 38 46 53 58 65 73 80 86 91 99 106 112 119 125 133 140 13 V 4.5 4.6 4.6 46 46 46 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 S 2.8 2.8 2.8 2 7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 2.7 X 62 62 62 63 63 63 63 63 63 63 63 64 64 64 64 64 64 O 37 44 51 59 66 74 82 90 96 103 III 119 127 134 142 150 158 .4 V 4.7 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.9 4.9 4.9 4.9 49 4.9 49 4.9 S 2.8 2.7 2.7 2.7 2.7 2.7 2.7 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 X 65 66 66 66 66 67 67 67 67 67 67 68 68 68 68 68 69 O 41 50 58 66 75 85 92 101 108 116 125 133 142 150 160 169 178 I.5 V 4.8 4.9 4.9 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.1 5.1 5.1 S 2.7 2.7 2.6 2.6 2.6 2.6 26 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.5 25 2.5 X 69 69 70 70 71 71 71 71 71 71 71 72 72 72 72 72 72 O 46 56 65 75 84 94 104 112 122 132 142 149 158 168 178 187 197 .6 V 5.0 5.1 5.1 5.1 5.1 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 5.2 S 2.6 2.6 2.6 2.6 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 X 72 74 74 75 75 76 76 76 76 76 76 , 76 76 76 76 76 76 O 52 62 72 83 94 105 115 126 135 145 156 167 175 187 196 206 217 I 7 V 5.2 5.2 5.2 5.3 5.3 5.3 5.3 5.4 5.4 5.4 5.4 5.4 5.4 5.41 5.4 5.4 5.4 S 2.6 2.6 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 X 76 78 79 80 80 80 80 BO 80 80 80 80 80 BO 80 60 80 0 58 69 81 93 104 I16 127 138 150 160 171 182 194 204 214 226 233 ' 8 V 5.3 5.4 5.4 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.6 5.6 56 5.6 5.6 5.6 S 2.5 2.5 2.5 2.5 2.4 2.4 24 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 X 80 82 83 84 84 84 ' 84 84 84 84 84 84 84 84 84 84 84 O 64 76 88' 102 114 127 140 152 164 1 75 188 201 213 225 235 248 260 1 y V 5.5 5.5 5.5 5.6 5.6 5.6 5.7 5.7 5.7 5.7 57 5.7 5.7 5.7 5.7 5.7 5.7 S 2.5 2.5 25 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 X 84 85 86 87 BB 88 88 88 BB 88 88 88 88 BB 88 88 88 O 71 83 97 III 125 138 153 164 178 193 204 218 232 245 256 /269 283 2 0 V 5.6 5.7 5.7 5.7 5.8 5.8 5.8 5.8 5.8 5.8 5.8 5.9 5.9 5.9 5.9 5.9 5.9 S 2.5 2.4 2.4 2 4 2.4 2 4 2.4 2.4 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 X 88 90 91 91 91 91 92 92 92 92 92 92 92 92 92 92 92 O 77 91 107 122 135 149 162 177 192 207 220 234 250 267 76 291 305 2 I V 5.7 5.8 5.9 5.3 5.9 5.9 59 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 S 2.4 2.4 2.4 24 2.4 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 X 92 93 95 95 95 95 95 95 95 96 96 96. 96 96 96 96 96 0 84 100 116 131 146 163 177 194 210 224 2.38 253 269 288 301 314 330 2 2 V 59 5.9 '6.0 6.0 6.06 6.1 6.1 6.1 6.1 6.1 6.1 6.1 6.1 62 6.2 6.2 6.2 S 2.4 2.4 2.4 2.3 2.31 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 X 96 96 99 99 99 99 99 100 100 100 100 100 100 100 100 100 100 O 90 108 124 140 158 175 193 208 226 243 258 275 292 306 323 34 1 354 2 3 V 6.0 6.1 6.1 6.1 62 62 6.2 6.2 6.3 6.3 6.3 6.3 6.3 6.3 6.3 6.3 6 3 S 2.4 2.4 2.3 23 23 2.3 23 2.3 2.2 2.2 2.2 2.2 22 2.2 2.2 2.2 2.2 X 100 102 102 103 103 103 104 104 104 105 105 105 105 105 105 105 105 0 99 I16 136 152 170 189 206 224 241 260 275 294 312 327 346 364 378 2 4 V 6.1 6.2 62 6 3 6.3 6.3 6 4 6.4 6.4 6.4 6.4 64 6 4 6.4 6.4 6.4 6.4 S 2 3 2 3 2.3 2.3 2.3 22 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.2 X 105 105 106 s.107 107 108 '108 108 `08 109 109 109 109 109 109 109 109 • • Source: USDA-SCS III - 100 1992 3.14 EXCAVATED EARTH SPILLWAY _- LEVEL PORTION q CREST AND CONTROL SECTION 1 _Al ill PIM A7-� FLOW -_�. I APPROACH a i ,...-- ppi ,� CHANNEL EXIT SECTOR I NOTE: NEITHER THE LOCATION I I NOR ALIGNMENT OF THE CONTROL SECTION HAS TO COINCIDE WITH THE CENTERUNE OF THE DAM. EMBANKMENT ► I A V R L - PLAN VIEW WATER SURFACE —\ X- LENGTH OF EXIT CHANNEL '` 1 STAGE (HP) \ CONTROL SECTION MAN• 20' EXIT SECTOR I LEVEL OR GREATER ' APPROACH - CHANNEL S PROFILE ALONG CENTERLINE 200' il I I— . .i I -Ngb 16- CROSS-SECTION AT CONTROL SECTION Source: USDA-SCS Plate 3.14-9 III - 101 1992 3.14 IX. Re-estimate the elevation of the design high water and the top of the dam based upon the design of the principal spillway and the emergency spillway. X. Anti-Vortex Device and Trash Rack A. This design procedure for the anti-vortex device and trash rack refers only to riser pipes of corrugated metal. There are numerous ways to provide protection for concrete pipe;these include various hoods and grates and rebar configurations which should be a part of project-specific design and will frequently be a part of a permanent structure. B. Refer to Plate 3.14-10 and Table 3.14-D. Choose cylinder size, support bars, and top requirements from Table 3.14-D based on the diameter of the riser pipe. XI. Anti-Seep Collars A. Anti-seep collars must be used under the conditions specified in the Design Criteria. B. Anti-seep collars are used to increase the seepage length along the barrel by 10%. C. Determine the length of the barrel within the saturated zone. This may be done graphically as in Plate 3.14-11 or by solving the following equation: Ls = Y (Z + 4) (1 + S 1 l 0.25 - S) where: Ls = length of barrel in the saturated zone, feet Y = the depth of water at the principal spillway crest, feet Z = slope of the upstream face of embankment in Z feet horizontal to one vertical S = slope of the barrel in feet per foot • D. Enter Plate 3.14-12 with Ls. Move horizontally right until one of the lines is intersected. Move vertically until the correct line for barrel diameter is intersected. Move horizontally right to read P,the size of the anti-seep collar. III - 102 ‘o el ANTI- VORTEX DEVICE DESIGN N PRESSURE RELIEF HOLES 1/2' DIA. O Cis A i��".�„ ``�\� A O I%�/� O TOP STIFFENER (IF REQUIRED) � / IS—X—X—ANGLE WELDED ;j TO TOP AND ORIENTED PER— L - - �—_ O / 0 PENDICULAR TO CORRUGATIONS. `\ / / /�� I p //; TOP IS GAGECORRUGATED p ��'.__, : p !/;/ O O METAL OR 1/8" STEEL PLATE. ` PRESSURE RELIEF HOLES MAY ,D BE OMMITTED, IF ENDS OF I CORRUGATIONS ARE LEFT FULLY PLAN VIEW OPEN WHEND THE TOP IS 0-4 �N D 'ED CYLINDER IS GAGE CORRUGATED TACKWELD 1� FABRICATED FROM FA RICA E PIPE OR B AROUND "'i ................................ ...... ....... ....... - METAL ALL [� :r ....................................................................... /411;74: - STEEL PLATE. S NOTES: 411Dio/.::i ;.. 8" MIN 1. THE CYLINDER MUST BE FIRMLY FASTENED TO THE TOP OF THE RISER. iiii .i). SUPPORT BAR SIZE WELDED x 12° 2. SUPPORT BARS ARE (#6 REBAR MIN.) SPACER BAR TO THE TOP OF THE RISER {TYPICAL OR ATTACHED BY STRAPS • •••••••••••••• ••• :: BOLTED TO TOP OF RISER. ' :::: ••••••••••••••••• RISER DIAMETER CD I W SECTION A-A ISOMETRIC W 1992 3.14 r TABLE 3.14-D CONCENTRIC TRASH RACK AND ANTI-VORTEX DEVICE DESIGN TABLE Riser Cylinder Minimum Top Diam., ' Height, Minimum Size in. Diameter, Thickness, inches Support Bar Thickness Stiffener inches gage 12 18 16 6 #6 Rebar or 11/2 x 16 ga. - 1'/z x 3/16 angle (F&C) 15 21 16 7 II ev - 18 27 16 8 - 21 30 16 11 " " 16 ga.(C), 14 - ga.(F) 24 36 16 13 " " " " — • 27 42 16 15 " " It " - 36 54 14 17 #8 Rebar 14 ga.(C), 12 - ga.(F) 42 60 16 19 — w •48 72 16 21 1'/4' pipe or 11/4 x 14 ga.(C), 10 - 1'/4 x' angle ga.(F) 54 78 16 25 " " " " - 60 90 14 29 11/2" pipe or 1' x 12 ga.(C), 8 - 1'/2 x 1/4 angle ga.(F) 66 96 14 33 2" pipe or 2 x 2 x 12 ga.(C), 8 2 x 2 x'/4 3/16 angle ga.(F) angle w/stiffener 72 102 14 36 " " " " 2' x 2' x '/4 angle 78 114 14 39 21/2' pipe or 2 x 2 x " " " " '/4 angle 84 120 12 42 21/2" pipe or 2' x " " 21/2 x 2'/2 x 2'/s x'/4 angle 5/16 angle Notes: The criterion for sizing the cylinder is that the area between the inside of the cylinder and the outside of the riser is equal to or greater than the area inside the riser. Therefore, the above table is invalid for use with concrete pipe risers. Note2: Corrugation for 12"-36" pipe measures 22/s"x'/z"; for 42" -84" the corrugation measures 5"x 1" or 8"x 1 Note3: C = corrugated; F = flat. Source: Adapted from USDA-SCS and Carl M. Henshaw Drainage Products Information. III - 104 1992 3.14 1 A , ,1200 ■MMM■■H■N■■■■■■N■■M■■M■■■HNM . 'y ■ ■■■■■■■■■■■■■■■■■■■■■■I■■■■■■■Ir �. q;• • ■ ► MMN■■N■IN■■■NM■■M■MN■N■M■M■M FA h' ■■ ■■■■■N. ■■■■■■■■■■■MMN■N■■■ .ti ti' O= ■■■ NN■NNM■H■■■MN■NMI■MMNM■N■ .■ N■■■ ■■■■■■MN■■■M■NMM■M■■■■■■■N ^b' .i ►■■■■o■■ IIu11i11IIII1u1111111111 iUiIIIi i 15 0 • 1 111111111111111111111,1111i1 1111 III II 1111111u111111111P /11/111un11 III 1�111111111111 1111112111111111111111 1■■■■■■■■ ■ ■■■■■■■■■H■■■■■■ al HN■ ■■■■■■■■ M Q� IY■ ■■■■M►NN ■■■■H ■■H ■I■■■■■■■■■■■ .FIVAU■■■■■■■I■■■■■■■■■■100 NNN■NNHH■ c) A/N/MNN■H ■N NN■■■NNMMII■ 0 ■■■■■■■■■■■ ■■r,■■■■■■■■■■■■■■■■■■ ■ J ■■N■N■N■■■■ c i■►AMMUM■■P■■■■■■■■ IM■M ■■■■■■■■■M 4P iIMMEMM ■M■■■■M■■■■■H■■■II L E M■■■■■ * //MENU■NNE■■■NNI■■HN■INN■ +3 ■■■■■■■ V II ■■I■■ ■■■■■■■■■■ ■■■■■■H■■ a mom 4,9 i►IIN■■■I■■■■N■N■N■■N■■■■■■M■■urns F. i/IH ■■ ■■■ M ■■■ N■■ ■ mJ MF !N11111iMM /gIi111111u uu50 iiimm 11 Qy. :1111:IIIIIIIIIIIMEMM IIIIIIIIII ro NMI iG■N■■NN■MHN■NM■N■NN■■■N■MN■■ N■ NM +3 111'd 111111111111u111111 1111111111 11 N !idHHllhlHflhlllllHllflhlllllllHll 0 u1111111111 I IIIuuIIIII 11u1 I1I111 Huhillll111f1111I1111111 111111 min ■■■■M■■■■■■N ■M■■■■■■■■■N■■. NN■■MN ■■ z0 nniu!iIHiiiiiNruuuI lPll InillNPiuu 11111111111111111111 ►1r11►111i1!11111I ■M■■■M■■■■■N■■■■ ■I■ o Am ■■■i■■■►.■■■ M■M■MNNMN■■NNNN■MM■M �, ' AMMVN■N►■■■■ ■■■■■■■■■■■■■M■■■■■Mr. iH►■■■!■■■■► MMMNNNNNMNNNMNMNI.w44U..r EMMEMMEMMIKM H■M■■N■■■■■■■■■ ammammmmamm ■■■■■■■■■■■■■■■■■II.N►IMI.■MI tcb i■■■■I■■■ 15 i■ii■iiiiiiiiiii■iginUVA■ n■ °i ii■ii ■■N■H■■■■■■■MM■■ANE i I.■■•I■■MM■ H■NIi ■■■■■MEN■■ ■■■MUMW I. PAII■■O■■■ ■ RAM ■■■■■■■■■■1■■■■■rmmm2ma■Era■■MME g■ ■■■■ MO iiiiiiiiiiii ii a,,/►,ins ■■ ►M■1=.. ■N■ NM■■■■NMMI■ %III ►NNI r4NMNN4■NM■■M■ ■■■■■■■■■■ x, AMOMPAVNNGs1P■■II►M■■■N■■H i11111111 O10101'I' 10 ■■■MEMO■ �_� , , ! ,' 1i1111 111111 y MUM QI►II/AI■O■■I■ PERI■ ■■ ■■MINI■ `� L 111111 11►.'/./"11111111111H■11111111111111 ■■■E■ •.� J4umm.V•P . d■MM ■■MEE■■HEM■M■■ ■E■■■ Q. A./././A►■►M■MNIN■■HN■■■H■■■HEN■ M■N■ k%/%%%I►�iNM� ■ N■ ■MMM■■■■MN■M■■N■■N UM o /���IIiM2■►.A■■■■■■■■■■■N■■■■■■■■■■■ M■■ /�►/IOPA■VAN■■■■■■■■■■■■■■■■■■■■■■■■ o ■■ Q'i'/,/I II EMENMEE■ EMNH■■NNE■■ ■■■■■■EN I.e,,'/: G//1111111111I111111111111IUI1I1 ■ %, 02MIE'M■M■ ■■■MMMM■■N ■■M■■■ME■■■■MOM 1i„` 4 ii111l 11i1i1i1111i1iu1i1111 • i ,r, 0 �' 1 f i 1 PIPE LENGTH IN SATURATED ZONE Source: USDA-SCS Plate 3.14-11 III - 105 . 1992 3.14 , , 11 A A .i A ' .41 .41 ■■■■■■■■■■■■.■■■■■ 6 • 5 ■■ 4 ■■ 3 ■ 2 ■■ 1 ■■■ 10 ■■■■■■■■■■■■■ ■■■ ■ ■■ ■■ II NM ■■■ .■■■■■■■■■■. ■M' ■' Ma ■% ■' .2 .■■ ■■.■■■■■■■■ e,- i■■■..■■■I.■■■I..■■IMIM■.M■■■■.■. ■■■■■..■■■ ke, iM■■■IA ►.■■■ ■■■.►■■■■►■■ ►.■■■■■■■■. c ■■■■■..■ I■■■.i■.■■i■■..G■■■■!■■■■/■.■.■■■.■■ ' ...■■.■ e' ' 4■■■.■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ ..■.■. e�a' i■..IA■■.MM■■■IM■..IM.■■M' ■■■■■■■■■■■ .4-)EMU■■ .i■■■i■■■■M■■.■iM■■.E■.■■►A 2 Collars F 0) II" q.o'�iIII/IIIIIIIIIIIIIIIIIII/III 7.3' x 7.3'll' �- ■ - ./■■■►n■■I%■■■■■■■RIA■■■■■■■■ ■ ■L■■■■ • Q AMPA ■ G'aiii7.GiiGCiGGiiiiGiGGiGGiiGiu ' ., ::. :.':::: :: :: : :: : :IMIMM:: illllli ■■P-■ IKINI ■INIM■■■�i■■■■.■■■■■u■ ■■ I11111luII/111I1111I/1IIIf111111II1111I1111111111I16 a; I/!11 . 11111111111111/111111111II 3 Collars 1i 21111111111111111111111111111111HIII 5.9' x 5.9' ■■5 (.' III 111111111111111111111111111111111111 II s.. 1.111I III IiiiiHIIIIIHUIIHllhhIHUHIHIOhIIIIHOI r C 111111I Collar Projection, V, feet 1111111111 • 2001111 HIIIIIIIIIIIIIIIIII;1®IIUIIIIIIIIIIIIIIIt ■.....■■■■■.■■■■■■■■■�■Y ■■..■�■■■■■■■■■� ■■..■ iliii�'�iiiuiiiiiiiiiiIiiiriiiiiiiiiiiiii�iriii i-). ■■ q ■■■■■■■■ ■II■.■.■/a..■■■■■■■■■■■Id■■■■■■ ■■■■■p■MU■■■■■■■■. t h M ■■.I■.■■■■■■■■■ ■.■■.■■■■■ N ■■■■■■■■■■■■■... Z I1 ■■II.■.■■■■■■■■■Ii■■■■■■■■■ 4— RIII•UEU•EUUUU• ;! A_ " .i=iiiii■•000UP I■■iiiiii•IU ., 150■■■■■■..■.■■■■■ 1 r ""Ei=iiii � ,'a Ui"Iiiii:iioi"i " Ammu ■■ i ■i •U I ..MMpM..■... JN• MM4•IUUUI ••U •I■■ ■■. . ■ A V A HU ■ U qp• ■ MAMEMEMEMMEMMIMMEMME loo :I::.'•U...•'.I:: •I.: ,ti .MOMMIMM ■ ::■:■■:■IIp:=:M■::::I:u�:: MMEMMMEWICA 0 E-J M■■■E■�ppNMuAAM E� ►np::EN■.■E■�■�u••Mr•�■• 0 ■■■■■■■■■■U■■ri■■■■.■A■■■f■.■■■ ■■■■■emr....I=■ "i.I, ►iII i iiiiil; i iiun�iii ■■ 1u�111I■••; V _d■■ ■■■■■■■U ■■■o■■N50r . � • Ap1 _.. , II pI IdI Note: This procedure is I r NIiIIIIIIIII for a 10% increase in the I ' _.iG■■■■■...■■■■ length of flow path. ■ rim;r4-..■ mum ■■■ ■ 0 ,,' i ; i l l , l l l l l l l l l l l l l l l l l l l l l l l NUMBER OF ANTI-SEEP COLLARS REQUIRED Source: USDA-SCS Plate 3.14-12 III - 106 1992 3.14 E. If more than one collar is used, the spacing between collars should be 14 times the projection of the collar above the barrel. F. Collars should not be located closer than 2 feet to a pipe joint. G. See Plate 3.14-13 for details of the anti-seep collar. XII. Anchoring the Principal Spillway A. The principal spillway must be firmly anchored to prevent its floating. B. If the riser is over 10 feet high, the forces acting on the spillway must be calculated. A method of anchoring the spillway which provides a safety factor of 1.25 must be used (downward forces = 1.25 x upward forces). C. If the riser is 10 feet or less in height, choose one of the two methods in Plate 3.14-14 to anchor the principal spillway. XIII. Dewatering A. Refer to Plate 3.14-15 for details and orientation. B. Calculation of the diameter of the dewatering orifice: Use a modified version of the discharge equation for a vertical orifice and a basic equation for the area of a circular orifice. Naming the variables: A = flow area of orifice, in square feet d = diameter of circular orifice;.in feet h = average driving head (maximum possible head measured from radius of orifice to crest of principal spillway divided by 2), in feet Q = volumetric flowrate through orifice needed to achieve approximate 6-hour drawdown, cubic feet per second S = total storage available in dry storage area, cubic feet Q = S / 21,600 seconds III - 107 1992 3.14 Use S for basin and find Q. Then substitute in calculated Q and find A: A = (64.32 x h 12 (0.6) Then, substitute in calculated A and find d: • (—A d* = 2x z 3.14 * Diameter of dewatering orifice should never be less than 3 inches in order to help prevent clogging by soil or debris. Note: Flexible tubing used should be at least 2 inches larger in diameter than the calculated orifice to promote improved flow characteristics. III - 108 1992 3.14 DETAILS OF CORRUGATED METAL ANTI-SEEP COLLAR INSTALL COLLAR WITH CORRUGATIONS VERTICAL rnIAR TO BE OF SAME GAGE AS THE PIPE WITH WHICH 1T IS USED CONTHUOUS WELD 1/T' X Y SLOTTED HOLES FOR El Y MINI 114_ re„ 3/r DIAMETER BOLTS. e e e , 1 B e e iT Y \.BAND / WELD BOTH SIDES SLOTTED HOLES CORRUGATED METAL CONTINUOUS WELD AT 8' C.C. SECTION B—B SHCHEET E DE 1,0 B ELEVATION OF UNASSEMBLED COLLAR 3. UNASSEMBLED COLLARS SHALL BE MARKED BY NOTES FOR COLLARS: PAINTING OR TAGGING TO IDENTIFY MATCHING PAIRS. 1. ALL MATERIALS TO BE IN ACCORDANCE WITH 4. THE LAP BETWEEN THE TWO HALF SECTIONS CONSTRUCTION AND CONSTRUCTION MATERIAL AND BETWEEN THE PIPE AND CONNECTING BAND SPECIFICATIONS. SHALL BE CAULKED WITH ASPHALT MASTIC AT 2. WHEN SPECIFIED ON THE PLANS, COATING OF TIME OF INSTALLATION. COLLARS SHALL BE IN ACCORDANCE WITH 5. EACH COLLAR SHALL BE FURNISHED WITH TWO CONSTRUCTION AND CONSTRUCTION MATERIAL 1/2' DIAMETER RODS WITH STANDARD TANK SPECIFICATIONS. LUGS FOR CONNECTING COLLARS TO PIPE. DETAIL OF HELICAL PIPE ANTI-SEEP COLLAR WELD SIZE AND SPACING OF SLOTTED ANGLE111IA^WIDE/AS SOWN/N ANGLES TO COLLAR OR BEND A 90' OPENINGS SHALL BE THE SAME NOTE FOR BANDS AND COLLARS: AS SHOWN FOR CM COLLAR. 1 1/5' MODIFICATIONS OF THE DETAILS USE RODS AND LUGS TO CLAMP SHOWN MAY BE USED PROVIDING BANDS SECURELY TO PIPE. 1 1�s' EQUAL WATERTIGHTNESS IS MAINTAINED AND DETAILED it MIN. I DRAWINGS ARE SUBMITTED AND APPROVED BY THE ENGINEER PRIOR -N\ TO DELIVERY. /I%414 HELICAL PIPE :rr ISOMETRIC VIEW 0:k BAND F A S ETAL COLLAR SHALL BE CUT TO F T CORRUGATIONS OF HELICALHAND,AND `' 1 ROD AM) LUG WELDED WITH A CONTINUOUS WELD. NOTE: FOR DETAILS OF FABRICATION DIMENSIONS, MINIMUM GAGES, SLOTTED HOLES, AND NOTES, SEE DETAIL ABOVE. METAL COLLAR TO BE NOTE: TWO OTHER TYPES OF ANTI—SEEP COLLARS ARE: WELDED TO CENTER CF I€UCaL PPE BAra 1. CORRUGATED METAL, SIMILAR TO UPPER, EXCEPT SHOP WELDED TO A SHORT (AFT.) SECTION OF THE PIPE AND CONNECTED WITH CONNECTING BANDS TO THE PIPE. PARTIAL ELEVATION 2. CONCRETE, SIX INCHES THICK FORMED AROUND THE PIPE REF: ENGR. FIELD WITH #3 REBAR SPACED 15" HORIZONTALLY AND VERTICALLY. Source: USDA-SCS Plate 3.14-13 III - 109 1992 3.14 RISER PIPE BASE CONDITIONS FOR EMBANKMENTS LESS THAN 10 ' HIGH CONCRETE BASE FOR EMBANKMENT 10' OR LESS IN HEIGHT 10' OR LESS t7 6" TIT : :Q 18" }/2 - .11 1�II I-; 11--7'1. 1II:711,:11=11=11=1h 2D —� CONCRETE STEEL BASE FOR EMBANKMENT 10' OR LESS IN HEIGHT 10' OR LESS D 1011: so" D/2 11=11=11=11-1111.11. . 11= 1.-11-11=11.=117-11=11= 11- 11.. 1_-117.11-1.,�.11. 2D 1/4" STEEL PLATE Source: Va. DSWC Plate 3.14-14 III - 110 1992 3.14 RECOMMENDED DE WA TERING S YS TEM FOR SEDIMENT BASINS PROVIDE ADEQUATE STRAPPING POLYETHYLENE CAP 1 L__7- DEPTHTACK VARIESASPERFORATED POLYETHYLENE* REQUIRED- DRAINAGE TUBING, DIAMETERFOR' DRY " VARIES (SEE CALCULATIONS INSTORAGE r r i �\ APPENDIX 3.14-A) A 1 wEf - " FERNCO-STYLE " COUPLING * STORAGE DEWATERING ORIFICE, 1 SCHEDULE 40 STEEL STUB 1-FOOT MINIMUM, DIAMETER VARIES (SEE CALCULATIONS IN CORRUGATED METAL RISER APPENDIX 3.14-A) NOTE: WITH CONCRETE RISER, USE PVC SCHEDULE 40 STUB FOR DEWATERING ORIFICE *DRAINAGE TUBING SHALL COMPLY WITH ASTM F667 AND AASHTO M294 Source: Va. DSWC Plate 3.14-15 III - 111 1992 3.14 TEMPORARY SEDIMENT BASIN DESIGN DATA SHEET (with or without an emergency spillway) Project Basin # Location Total area draining to basin: acres. Basin Volume Design Wet Storage: 1. Minimum required volume = 67 cu. yds. x Total Drainage Area (acres). 67 cu. yds. x acres = cu. yds. 2. Available basin volume = cu. yds. at elevation . (From storage - elevation curve) 3. Excavate - cu. yds. to obtain required volume*. * Elevation corresponding to required volume = invert of the dewatering orifice. 4. Available volume before cleanout required. 33 cu. yds. x acres = cu. yds. 5. Elevation corresponding to cleanout level = (From Storage - Elevation Curve) 6. Distance from invert of the dewatering orifice to cleanout level = ft. (Min. = 1.0 ft.) Dry Storage: 7. Minimum required volume = 67 cu. yds. x Total Drainage Area (acres). 67 cu. yds. x acres = cu. yds. III - 112 1992 3.14 8. Total available basin volume at crest of riser* = cu. yds. at elevation . (From Storage - Elevation Curve) * Minimum = 134 cu. yds./acre of total drainage area. 9. Diameter of dewatering orifice = in. 10. Diameter of flexible tubing = _ in. (diameter of dewatering orifice plus 2 inches). Preliminary Design Elevations 11. Crest of Riser = Top of Dam = Design High Water = Upstream Toe of Dam = Basin Shape 12. Length of Flow L = Effective Width We If > 2, baffles are not required If < 2, baffles are required Runoff 13. Q2 = cfs (From Chapter 5) 14. Q25 = cfs (From Chapter 5) Principal Spillway Design 15. With emergency spillway, required spillway capacity Qp = Q2 = cfs. (riser and barrel) Without emergency spillway, required spillway capacity Qp = Q25 = cfs. (riser and barrel) III - 113 1992 3.14 16. With emergency spillway: Assumed available head (h) = ft. (Using Q2) h = Crest of Emergency Spillway Elevation - Crest of Riser Elevation Without emergency spillway: Assumed available head (h) = ft. (Using Q25) h = Design High Water Elevation - Crest of Riser Elevation 17. Riser diameter (Dr) = in. Actual head (h) = ft. (From Plate 3.14-8.) Note: Avoid orifice flow conditions. 18. Barrel length (1) = ft. Head (H) on barrel through embankment = ft. (From Plate 3.14-7). 19. Barrel diameter = in. (From Plate 3.14-B [concrete pipe] or Plate 3.14-A [corrugated pipe]). 20. Trash rack and anti-vortex device Diameter = inches. Height = inches. (From Table 3.14-D). Emergency Spillway Design 21. Required spillway capacity Qe = Q25 - Qp = cfs. 22. Bottom width (b) = ft.; the slope of the exit channel (s) = ft./foot; and the minimum length of the exit channel (x) = ft. (From Table 3.14-C). III - 114 1992 3.14 Anti-Seep Collar Design 23. Depth of water at principal spillway crest (Y) = ft. Slope of upstream face of embankment (Z) = :1. Slope of principal spillway barrel (Sb) = Length of barrel in saturated zone (La) = ft. 24. Number of collars required = dimensions = (from Plate 3.14-12). Final Design Elevations 25. Top of Dam = Design High Water = Emergency Spillway Crest = Principal Spillway Crest = Dewatering Orifice Invert = Cleanout Elevation = Elevation of Upstream Toe of Dam or Excavated Bottom of "Wet Storage Area" (if excavation was performed) = III - 115 1992 3.05 STD & SPEC 3.05 x-x--x--x SILT FENCE0 Definition A temporary sediment barrier consisting of a synthetic filter fabric stretched across and attached to supporting posts and entrenched. Purposes 1. To intercept and detain small amounts of sediment from disturbed areas during construction operations in order to prevent sediment from leaving the site. 2. To decrease the velocity of sheet flows and low-to-moderate level channel flows. • i w t., , '4� �',: .. ., � 07'`"-`Ian * a„:.d i .al'" ter'.`^• t 4"z y„ .r '� j aW. .sue III - 19 1992 3.05 Conditions Where Practice Applies 1. Below disturbed areas where erosion would occur in the form of sheet and rill erosion. 2. Where the size of the drainage area is no more than one quarter acre per 100 feet of silt fence length; the maximum slope length behind the barrier is 100 feet; and the maximum gradient behind the barrier is 50 percent (2:1). 3. In minor swales or ditch lines where the maximum contributing drainage area is no greater than 1 acre and flow is no greater than 1 cfs. 4. Silt fence will not be used in areas where rock or some other hard surface prevents the full and uniform depth anchoring of the barrier. Planning Considerations Laboratory work at the Virginia Highway and Transportation Research Council (VHTRC) has shown that silt fences can trap a much higher percentage of suspended sediments than straw bales, though silt fence passes the sediment-laden water slower. Silt fences are preferable to straw barriers in many cases because of their durability and potential cost savings. While the failure rate of silt fences is lower than that of straw barriers, many instances have been observed where silt fences are improperly installed, inviting failure and sediment loss. The installation methods outlined here can improve performance and reduce failures. As noted, flow rate through silt fence is significantly lower than the flow rate for straw bale barriers. This creates more ponding and hence more time for sediment-to fall out. Table 3.05-A demonstrates these relationships. Both woven and non-woven synthetic fabrics are commercially available. The woven fabrics generally display higher strength than the non-woven fabrics and, in most cases, do not require any additional reinforcement. When tested under acid and alkaline water conditions, most of the woven fabrics increase in strength,while the reactions of non-woven fabrics to these conditions are variable. The same is true of testing under extensive ultraviolet radiation. Permeability rates vary regardless of fabric type. While all of the fabrics demonstrate very high filtering efficiencies for sandy sediments, there is considerable variation among both woven and non-woven fabrics when filtering the finer silt and clay particles. Design Criteria 1. No formal design is required. As with straw bale barriers, an effort should be made to locate silt fence at least 5 feet to 7 feet beyond the base of disturbed slopes with grades greater than 7%. - III - 20 1992 3.05 TABLE 3.05-A TYPICAL FLOW RATES AND FILTERING EFFICIENCIES OF PERIMETER CONTROL Flow Rate Filter Material (gal./sq.ft./min) Efficiency(%) Straw 5.6 67 Synthetic Fabric 0.3 97 Source: VHTRC 2. The use of silt fences, because they have such a low permeability, is limited to situations in which only sheet or overland flows are expected and where concentrated flows originate from drainage areas of 1 acre or less. 3. Field experience has demonstrated that, in many instances, silt fence is installed too short (less than 16 inches above ground elevation). The short fence is subject to breaching during even small storm events and will require maintenance "clean outs" more often. Properly supported silt fence which stands 24 to 34 inches above the existing grade tends to promote more effective sediment control. Construction Specifications Materials 1. Synthetic filter fabric shall be a pervious sheet of propylene, nylon, polyester or ethylene yarn and shall be certified by the manufacturer or supplier as conforming to the requirements noted in Table 3.05-B. 2. Synthetic filter fabric shall contain ultraviolet ray inhibitors and stabilizers to provide a minimum of six months of expected usable construction life at a temperature range of 0° F to 120° F. 3. If wooden stakes are utilized for silt fence construction, they must have a diameter of 2 inches when oak is used and 4 inches when pine is used. Wooden stakes must have a minimum length of 5 feet. • III - 21 1992 3.05 TABLE 3.05-B PHYSICAL PROPERTIES OF FILTER FABRIC IN SILT FENCE Physical Property Test Requirements Filtering Efficiency ASTM 5141 75% (minimum) Tensile Strength at VTM-52 Extra Strength - 20% (max.) Elongation* 50 lbs./linear inch (minimum) Standard Strength- 30 lbs./linear inch (minimum) • • Flow Rate ASTM 5141 0.2 gal./sq.ft./ minute(minimum) Ultraviolet Radiation ASTM-G-26 90% (minimum) Stability % * Requirements reduced by 50% after six months of installation. Source: VHTRC 4. If steel posts (standard"U"or"T'section) are utilized for silt fence construction,they must have a minimum weight of 1.33 pounds per linear foot and shall have a minimum length of 5 feet. 5. Wire fence reinforcement for silt fences using standard-strength filter cloth shall be a minimum of 14 gauge and shall have a maximum mesh spacing of 6 inches. Installation 1. The height of a silt fence shall be a minimum of 16 inches above the original ground surface and shall not exceed 34 inches above ground elevation. III - 22 1992 3.05 2. The filter fabric shall be purchased in a continuous roll cut to the length of the barrier to avoid the use of joints. When joints are unavoidable, filter cloth shall be spliced together only at a support post,with a minimum 6-inch overlap, and securely sealed. 3. A trench shall be excavated approximately 4-inches wide and 4-inches deep on the upslope side of the proposed location of the measure. 4. When wire support is used, standard-strength filter cloth may be used. Posts for this type of installation shall be placed a maximum of 10-feet apart (see Plate 3.05-1). The wire mesh fence must be fastened securely to the upslope side of the posts using heavy duty wire staples at least one inch long, tie wires or hog rings. The wire shall extend into the trench a minimum of two inches and shall not extend more than 34 inches above the original ground surface. The standard-strength fabric shall be stapled or wired to the wire fence, and 8 inches of the fabric shall be extended into the trench. The fabric shall not be stapled to existing trees. 5. When wire support is not used, extra-strength filter cloth shall be used. Posts for this type of fabric shall be placed a maximum of 6-feet apart (see Plate 3.05-2). The filter fabric shall be fastened securely to the upslope side of the posts using one inch long (minimum) heavy-duty wire staples or tie wires and eight inches of the fabric shall be extended into the trench. The fabric shall not be stapled to existing trees. This method of installation has been found to be more commonplace than #4. 6. If a silt fence is to be constructed across a ditch line or swale, the measure must be of sufficient length to eliminate endflow, and the plan configuration shall resemble an arc or horseshoe with the ends oriented upslope(see Plate 3.05-2). Extra-strength filter fabric shall be used for this application with a maximum 3-foot spacing of posts. All other installation requirements noted in #5 apply. 7. The 4-inch by 4-inch trench shall be backfilled and the soil compacted over the filter fabric. 8. Silt fences shall be removed when they have served their useful purpose, but not before the upslope area has been permanently stabilized. III - 23 1992 3.05 CONSTRUCTION OF A SILT FENCE (WITH WIRE S UPPOR T) 1. SET POSTS AND EXCAVATE A 4"X4" 2. STAPLE WIRE FENCING TO THE POSTS. TRENCH UPSLOPE ALONG THE LINE OF POSTS. .... '! i 1011111111 1111:111:2.1111E. ‘.1 4 „ ........,... _III _- .___- ,......- ...___.- ,,, i ; ______, 7 ______./ .._ FLOW 1IIIii III 111I1 -1II"7. 4" 3. ATTACH THE FILTER FABRIC TO THE WIRE 4. BACKFILL AND COMPACT THE FENCE AND EXTEND IT INTO THE TRENCH. EXCAVATED SOIL. ' - ' .' i IFfl ' f 'a 1 t ` \ tt s rr , .41P 1 1tl KY\ ' r 4s+i. i k % ,. i 1\. •, '4' / v► , .0 i:�i / �i • 4iii9.. • • II.1 10 %`` . \'R\ ',0,: — 7,7,...... ••"'':f - _ ,,,,. R4 _ - ! ., 1y;;s"\ III 4'04 w0.,,,. fir ,i , _ill i lWLL I�� II FLOW �iill 1.01.,j_ = - IIII Ili _ II'r =11III III''' EXTENSION OF FABRIC AND WIRE INTO THE TRENCH. FILTER FABRIC 71 LI•iI� Ill WIR_I IIIIII . —I Source: Adapted from Installation of Straw and Fabric Filter Barriers for Sediment Control, Sherwood and Wyant Plate 3.05-1 III - 24 1992 3.05 CONSTRUCTION OF A SILT FENCE (WITHOUT WIRE S UPPOR T) 1. SET THE STAKES. 2. EXCAVATE A 4"X 4" TRENCH UPSLOPE ALONG THE LINE OF STAKES. 6'MAX.11;fil [flf II I �! � - -.y,(�i ' III I r7 ---.- ---:;--- —_ FLOW / / — IIII I"• III "" 4" 3. STAPLE FILTER MATERIAL 4. BACKFILL AND COMPACT TO STAKES AND EXTEND THE EXCAVATED SOIL. IT INTO THE TRENCH. 'i, m ir i+ m -.Jr V • �s+ , ,s t ' �\, t i\ yyf((p��►t t 1 \�l t.�7t 51 t11 ' • t', e51.. ` !�;:i;j \ t� f1 t t 1'4 '1 �4`It ;11 tii / I/I - l `tit 1 I t�l l L /J td`�►�:•1 ll 1 tt 4l - ':; / '• •• '`1 v. „+;:?.J.•• III ^ :i:';ir S = IIII = IIII IP I I FLOW --- liIII I Ili _ ''''' - Iu 1=a SHEET FLOW INSTALLATION (PERSPECTIVE VIEW) I A 'l I n r-I. .;.! A ;:>\;,;:1' FLOW `:, / // i / 111111-110 POINTS A SHOULD BE HIGHER THAN POINT B. DRAINAGEWAY INSTALLATION (FRONT ELEVATION) Source: Adapted from Installation of Straw and Fabric Filter Barriers for Sediment Control, Sherwood and Wyant Plate 3.05-2 III - 25 1992 3.05 Maintenance • 1. Silt fences shall be inspected immediately after each rainfall and at least daily during prolonged rainfall. Any required repairs shall be made immediately. 2. Close attention shall be paid to the repair of damaged silt fence resulting from end runs and undercutting. 3. Should the fabric on a silt fence decompose or become ineffective prior to the end of the expected usable life and the barrier still be necessary, the fabric shall be replaced promptly. 4. Sediment deposits should be removed after each storm event. They must be removed when deposits reach approximately one-half the height of the barrier. 5. Any sediment deposits remaining in place after the silt fence is no longer required shall be dressed to conform with the existing grade, prepared and seeded. III - 26 1992 3.19 STD & SPEC 3.19 RIPRAP0 Definition A permanent, erosion-resistant ground cover of large, loose, angular stone with filter fabric or granular underlining. Purposes 1. To protect the soil from the erosive forces of concentrated runoff. 2. To slow the velocity of concentrated runoff while enhancing the potential for infiltration. 3. To stabilize slopes with seepage problems and/or non-cohesive soils. pry, 'q ....,, 4.4.w-s�'. , 1'� p • i� �'`.r yr # S - `., .'/;,� �.y. ,,w r • -, .., & x'.. .,.I.'. «�.- ,r• „,� S .* F ^ .*. l 7"Y + �« K '" k '.. " '"A..'r it .«.R ,3'' • . io, • -WV..' ,'.'` 'i Q�.'a.. `` ...a • ' ,......,'r - .. L w it - ' :r,t:. 2 M.. - ...' ?�( ,w'k .. 4 ilk -, fii?; .*: ... ‘ lit- .,t„*„_-.......:._ ,,,, rr y it F. T . y `'F �M h,*." mow:.r34# ' ...w'R . ,w M ayi� ` ,' f �. III - 166 1992 3.19 Conditions Where Practice Applies Wherever soil and water interface and the soil conditions, water turbulence and velocity, expected vegetative cover, etc., are such that the soil may erode under the design flow conditions. Riprap may be used, as appropriate, at stormdrain outlets, on channel banks and/or bottoms, roadside ditches, drop structures, at the toe of slopes, as transition from concrete channels to vegetated channels, etc. Planning Considerations Graded vs. Uniform Riprap Riprap is classified as either graded or uniform. A sample of graded riprap would contain a mixture of stones which vary in size from small to large. A sample of uniform riprap would contain stones which are all fairly close in size. For most applications, graded riprap is preferred to uniform riprap. Graded riprap forms a flexible self-healing cover, while uniform riprap is more rigid and cannot withstand movement of the stones. Graded riprap is cheaper to install, requiring only that the stones be dumped so that they remain in a well-graded mass. Hand or mechanical placement of - individual stones is limited to that necessary to achieve the proper thickness and line. Uniform riprap requires placement in a more or less uniform pattern, requiring more hand or mechanical labor. Riprap sizes can be designed by either the diameter or the weight of the stones. It is often misleading to think of riprap in terms of diameter, since the stones should be angular instead of spherical. However, it is simpler to specify the diameter of an equivalent size of spherical stone. Table 3.19-A lists some typical stones by weight, spherical diameter and the corresponding rectangular dimensions. These stone sizes are based upon an assumed specific weight of 165 lbs./ft3. Since graded riprap consists of a variety of stone sizes, a method is needed to specify the size range.of the mixture of stone. This is done by specifying a diameter of stone in the mixture for which some percentage, by weight, will be smaller. For example, d85 refers to a mixture of stones in which 85%of the stone by weight would be smaller than the diameter specified. Most designs are based on d50. In other words,the design is based on the average size of stone in the mixture. Table 3.19-B lists VDOT standard graded riprap sizes by diameter the weight of the stone. To ensure that stone of substantial weight is used when implementing riprap structures, specified weight ranges for individual stones and composition requirements should be followed. Such guidelines will help to prevent inadequate stone from being used in construction of the measures and will promote more consistent stone classification statewide. Table 3.19-C notes these requirements. III - 167 1992 3.19 TABLE 3.19-A SIZE OF RIPRAP STONES Mean Spherical Angular Shape: Weight Diameter Length Width, Height (lbs.) (ft.) (ft.) (ft.) 50 0.8 1.4 0.5 100 1.1 1.75 0.6 150 1.3 2.0 0.67 300 1.6 2.6 0.9 500 1.9 3.0 1.0 1,000 2.2 3.7 1.25 1,500 2.6 4.7 1.5 2,000 2.75 5.4 1.8 4,000 3.6 6.0 2.0 6,000 4.0 6.9 2.3 8,000 4.5 7.6 2.5 20,000 6.1 10.0 3.3 Source: VDOT Drainage Manual Sequence of Construction Since riprap is used where erosion potential is high, construction must be sequenced so that the riprap is put in place with the minimum possible delay. Disturbance of areas where riprap is to be placed should be undertaken only when final preparation and placement of the riprap can follow immediately behind the initial disturbance. Where riprap is used for outlet protection, the riprap should be placed before or in conjunction with the construction of the pipe or channel so that it is in place when the pipe or channel begins to operate. Design Criteria Gradation The riprap shall be composed of a well-graded mixture down to the one-inch size particle such that 50% of the mixture by weight shall be larger than the d50 size as determined from the design procedure. A well-graded mixture as used herein is defined as a mixture composed primarily of the larger stone sizes but with a sufficient mixture of other sizes to fill the progressively smaller voids between the stones. The diameter of the largest stone size in such a mixture shall be 12 times the d50 size. III - 168 1992 3.19 TABLE 3.19-B GRADED RIPRAP - DESIGN VALUES Mean Dis Mean D50 D15 Spherical Spherical Riprap Weight Diameter Diameter Class (lbs.) (ft.) (ft.) Class AI 25 0.7 0.9 Class I 50 0.8 1.1 Class II 150 1.3 1.6 Class III 500 1.9 2.2 Type I 1,500 2.6 2.8 Type II 6,000 4.0 4.5 Source: VDOT Drainage Manual The designer, after determining the riprap size that will be stable under the flow conditions, shall consider that size to be a minimum size and then, based on riprap gradations actually available in the area, select the size or sizes that equal or exceed the minimum size. The possibility of damage by children shall be considered in selecting a riprap size, especially if there is nearby water or a gully in which to toss the stones. Thickness The minimum thickness of the riprap layer shall be 2 times the maximum stone diameter, but not less than 6 inches. Quality of Stone Stone for riprap shall consist of field stone or rough unhewn quarry stone of approximately rectangular shape. The stone shall be hard and angular and of such quality that it will not disintegrate on exposure to water or weathering and it shall be suitable in all respects for the purpose intended. The specific gravity of the individual stones shall be at least 2.5. Rubble concrete may be used provided it has a density of at least 150 pounds per cubic foot, and otherwise meets the requirement of this standard and specification. III - 169 1992 3.19 TABLE 3.19-C GRADED RIPRAP - WEIGHT ANALYSIS Riprap Weight Requirements for Class/Type Range* (lbs.) Stone Mixture Class AI 25-75 Max. 10% > 75 lbs. Class I 50-150 60% > 100 lbs. Class II 150-500 50% > 300 lbs. Class III 500-1,500 50% > 900 lbs. Type I 1,500-4,000 Av. wt. = 2,000 lbs. Type II 6,000-20,000 Av. wt. = 8,000 lbs. * In all classes/types of riprap, a maximum 10% of the stone in the mixture may weigh less than the lower end of the range. Source: Adapted from VDOT Road and Bridge Specifications Filter Fabric Underlining A lining of engineering filter fabric (geotextile) shall be placed between the riprap and the underlying soil surface to prevent soil movement into or through the riprap. Table 3.19-D notes the minimum physical properties of the filter fabric. Filter fabric shall not be used on slopes greater than 1 i:1 as slippage may occur and should be used in conjunction with a layer of course aggregate (granular filter blanket is described below) when the riprap to be placed is Class II or larger. Granular Filter Although the filter cloth underlining or bedding is the preferred method of installation, a granular (stone) bedding is a viable option when the following relationship exists: III - 170 1992 3.19 dls filter < 5 < do filter < 40 do base do base and, d5,3 filter < 40 d50 base In these relationships,filter refers to the overlying material and base refers to the underlying material. The relationships must hold between the filter material and the base material and between the riprap and the filter material. In some cases, more than one layer of filter material may be needed. Each layer of filter material should be approximately 6-inches thick. TABLE 3.19-D REQUIREMENTS FOR FILTER FABRIC USED WITH RIPRAP Physical Property Test Method Requirements Equivalent Corps of Engineers Equal or greater than Opening Size CWO 2215-77 U.S. No. 50 sieve Tensile Strength* VTM-52 30 lbs./linear in. @ 20% (maximum) (minimum) Puncture Strength ASTM D751* 80 lbs. (minimum) * Tension testing machine with ring clamp, steel ball replaced with 5/16 diameter solid steel cylinder with hemispherical tip centered within the ring clamp. Seams shall be equal in strength to basic material. Additional fabric material or non-corrosive steel wire may be incorporated into the fabric to increase overall strength. • Source: VDOT Road and Bridge Specifications III - 171 1992 3.19 Riprap at Outlets Design criteria for sizing the stone and determining the dimensions of riprap pads used at the outlet of drainage structure are contained in OUTLET PROTECTION (Std. & Spec. 3.18). A filter fabric underlining is required for riprap used as outlet protection. Riprap for Channel Stabilization Riprap for channel stabilization shall be designed to be stable for the condition of bank-full flow in the reach of channel being stabilized. The design procedure in Appendix 3.19-a, which is extracted from the Federal Highway Administration's Design of Stable Channels with flexible Linings (82), shall be used. This method establishes the stability of the rock material relative to the forces exerted upon it. Riprap shall extend up the banks of the channel to a height equal to the maximum depth of flow or to a point where vegetation can be established to adequately protect the channel. The riprap size to be used in a channel bend shall extend upstream from the point of curvature and downstream from the bottom of the channel to a minimum depth equal to the thickness of the blanket and shall extend across the bottom of the channel the same distance (see Plate 3.19-1). Freeboard and Height of Bank For riprapped and other lined channels,the height of channel lining above the water surface should be based on the size of the channel, the flow velocity, the curvature, inflows, wind action, flow regulation, etc. The height of the bank above the water surface varies in a similar manner, depending on the above factors plus the type of soil. Plate 3.19-2 is based on information developed by the U.S. Bureau of Reclamation for average freeboard and bank height in relation to channel capacity. This chart should be used by the designer to obtain a minimum freeboard for placement of riprap and top of bank. Riprap for Slope Stabilization Riprap for slope stabilization shall be designed so that the natural angle of repose of the stone mixture is greater than the gradient of the slope being stabilized (see Plate 3.19-5). Riprap for Lakes and Ponds Subject to Wave Action Riprap used for shoreline protection on lakes and ponds may be subject to wave action. The waves affecting the shoreline may be wind-driven or created by boat wakes. Consult III - 172 1992 3.19 TOE REQUIREMENTS FOR BANK STABILIZATION FILTER CLOTH UNDERLINER (PREFERRED) XEY IN • 1141‘FILTER CLOTH *eh 406. o1 MIN. &A ry FILTER CLOTH 10, GRANULAR FILTER MIN. l&APOPO 4‘if COARSE AGGREGATE MIN. THICKNESS = 6" Source: Adapted from VDOT Drainage Manual Plate 3.19-1 III - 173 1992 3.19 RECOMMENDED FREEBOARD AND HEIGHT OF BANK OF LINED CHANNELS 5 4 S‘31°PG 3 °s‘ � FS SV0. P 2 ISO \OTC 0 10 20 30 50 100 200 300 500 1000 2000 4000 CAPACITY, CFS. Source: U. S. Bureau of Reclamation Plate 3.19-2 III - 174 1992 3.19 the latest edition of the VDOT Drainage Manual ("Design of Slope Protection to Resist Wave Action") for specific design criteria in determining the required size of stones and the design wave height for such an installation. Use the equations in Appendix 3.19-b to calculate other pertinent design parameters. For more in-depth design criteria concerning these installations, see the U.S. Army Corps of Engineers' Shore Protection Manual (59). Riprap for Abrupt Channel Contractions Refer to latest edition of VDOT Drainage Manual. Riprap for Installations Subject to Tidal and Wave Action The design of riprap structures for tidal areas is beyond the scope of the VESCL and VESCR. The DSWC's Shoreline Programs Bureau provides advice regarding minimum design parameters for these installations. Notably, a riprap design for shoreline protection in tidal areas must meet all applicable state and federal requirements and should be carried out by a qualified professional. Construction Specifications Subgrade Preparation: The subgrade for the riprap or filter shall be prepared to the required lines and grades. Any fill required in the subgrade shall be compacted to a density approximately that of the surrounding undisturbed material. Brush, trees, stumps and other objectionable material shall be removed. Filter Fabric or Granular Filter: Placement of the filter fabric should be done immediately after slope preparation. For granular filters, the stone should be spread in a uniform layer to the specified depth (normally 6 inches). Where more than one layer of filter material is used, the layer should be spread so that there is minimal mixing of the layers. When installing geotextile filter cloths, the cloth should be placed directly on the prepared slope. The edges of the sheets should overlap by at least 12 inches. Anchor pins, 15 inches long, should be spaced every 3 feet along the overlap. The upper and lower ends of the cloth should be buried at least 12 inches. Care should be taken not to damage the cloth when placing the riprap. If damage occurs,that sheet should be removed and replaced. For large stone (Class II or greater), a 6-inch layer of granular filter will be necessary to prevent damage to the cloth. Stone Placement: Placement of riprap should follow immediately after placement of the filter. The riprap should be placed so that it produces a dense well-graded mass of stone with a minimum of voids. The desired distribution of stones throughout the mass may be obtained by selective loading at the quarry, controlled dumping of successive loads during final placing, or by a combination of these methods. The riprap should be placed to its full thickness in one operation. The riprap should not be placed in layers. The riprap should not be placed by dumping into chutes or similar methods which are likely to cause III - 175 1992 3.19 segregation of the various stone sizes. Care should be taken not to dislodge the underlying material when placing the stones. The finished slope should be free of pockets of small stone or clusters of large stones. Hand placing may be necessary to achieve the required grades and a good distribution of stone sizes. Final thickness of the riprap blanket should be within plus or minus 1/4 of the specified thickness. Maintenance Once a riprap installation has been completed, it should require very little maintenance. It should, however, be inspected periodically to determine if high flows have caused scour beneath the riprap or filter fabric or dislodged any of the stone. Care must be taken to properly control sediment-laden construction runoff which may drain to the point of the new installation. If repairs are needed, they should be accomplished immediately. III - 176 1992 3.19 APPENDIX 3.19-a RIPRAP DESIGN IN CHANNEL The design method described below is adapted from Hydraulic Engineering Circular No. 15 of the Federal Highway Administration. It is applicable to both straight and curved sections of channel where the flow is tangent to the bank of the channel. Tangent Flow - Federal Highway Administration Method This design method determines a stable rock size for straight and curved sections of channels. It is assumed that the shape, depth of flow, and slope of the channel are known. A stone size is chosen for the maximum depth of flow. If the sides of the channel are steeper than 3:1, the stone size must be modified accordingly. The final design size will be stable on both sides of the channel and the bottom. 1. Enter Plate 3.19-3 with the maximum depth of flow (feet) and channel slope (feet/foot). Where the two lines intersect, choose the dso size of stone. (Select the d50 for the diagonal line above the point of intersection). 2. If channel side slopes are steeper than 3:1, continue with step 3; if not, the procedure is complete. 3. Enter Plate 3.19-4 with the side slope and the base width to maximum depth ratio (B/d). Where the two lines intersect, move horizontally left to read Kl. 4. Determine from Plate 3.19-5 the angle of repose for the dso size of stone and the side slope of the channel. (Use 42° for dso greater than 1.0. Do not use riprap on slopes steeper than the angle of repose for the size of stone). 5. Enter Plate 3.19-6 with the side slope of the channel and the angle of repose for the dso size of stone. Where the two lines intersect, move vertically down to read k2. 6. Compute dso x Kl/K2 = d'50 to determine the correct size stone for the bottom and side slopes of straight sections of channel. For Curved Sections of Channel 1. Compute the radius of the curve (Ro), measured at the outside edge of the bottom. 2. Compute the ratio of the top width of the water surface (Bs) to the radius of the curve (Ro), Bs/Ro. 3. Enter Plate 3.19-7 with the radio Bs/Ro. Move vertically until the curve is intersected. Move horizontally left to read K3. III - 177 1992 3.19 4. Compute d'50 x K3 = d50c to determine the correct size stone for bottom and side slopes of the curved sections of channel. Example Problem Given: A trapezoidal channel 3 feet deep, 8 foot bottom width, 2:1 side slopes, and a 2% slope. Calculate: A stable riprap size for the bottom and side slopes of the channel. Solution: 1. From Plate 3.19-3, for a 3-foot-deep channel on a 2% grade, d50 = 0.75 feet or 9 inches. 2. Since the side slopes are steeper than 3:1, continue with step 3. 3. From Plate 3.19-4, B/d = 8/3 = 2.67, Z = 2, Kl = 0.82. 4. From Plate 3.19-5, for d50 = 9 inches, = 41°. 5. From Plate 3.19-6, for Z = 2 and = 41°, K2 = 0.73. 6. d50 x Kl/k2 = d'50 = 0.75 x 0.82/0.73 = 0.84 feet. 0.84 feet x 12 inches = 10.08. Use d'50 = 10 inches. 1 foot III - 178 1992 3.19 Given: The preceding channel has a curved section with a radius of 50 feet. Calculate: A stable riprap size for the bottom and side slopes of the curved section of channel. Solution: 1. Ro = 50 feet 2. Bs/Ro = 20/50 = 0.40 3. From Plate 3.19-7, for Bs/Ro = 0.40, K3 = 1.1 4. d'50 x K3 = 0.84 x 1.1 = 0.92 feet 0.92 feet x 12 inches = 11.0. 1 foot III - 179 1992 3.19 20.0 MN:�liiUUuuuuuii iii=iiHUiilI UuiuIiuIIiuIHHhuIIIl• iiiioi . Emir"mm111...MII.1.111II111111111IIIII IIIIIIIII M111 111 l l uiiiiiiiiii.I r..Iuu..luulIuuIIIuuuuIIIuuIII muluR111III1I1IIIIIIIUII. ......ui 1IIIII11111IIIIIIII111IIIIIIIII�IIIUUUII;;; 10.0 ' 1. 1111IIBII 1I 11 IIIIIUI111 1111i' s = -_=_---___-MINE.... _ ==___==_ IffillifigiMal- o. -... .._.-....... ... = EE== Ia�o0 �:: b� �1.::1:.1i7::1 YYN-I.MI.MI I• �\ EZZ= \ a .I.w YYN-=.... �v Y�I�-. Y w.w YY -�=... ' DAL-i�■-I..7..... 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IIMENIMMINEMIN111111111111111111111111111111111111111111111111111111111MMIMIIIMENI IIIIIIM■■■■■■IIIIIIIIIIIIIM1111111111IIIII I1111IINIIIIIII1111III IN■M■\\i■i1 uM■■E■i111111M111111111IIII111111111111111111111111III IIIII IIIIINIMMIENU■11 •■I■■■■I11111111111111111111IIIIIIIIIIII1111111111111111IIIIII1II•■1.11Mi a 0.1 •■••••11111111111111111111III1I111111111111111111111I111......■1SS 0.01 0.02 0.05 0.1 0.2 Channel Slope, feet/foot MAXIMUM DEPTH OF FLOW FOR RIPRAP LINED CHANNELS Source: VDOT Drainage Manual Plate 3.19-3 III - 180 1992 3.19 1.2 1.1 - 1.0 ` Side Slope 4:1 0.9 3:1 0.8 2:1 1.5:1 — 0.7 - 0.6 0.5 0 2 4 6 8 10 B/d DISTRIBUTION OF BOUNDARY SHEAR AROUND WETTED PERIMETER OF TRAPEZOIDAL CHANNEL Source: VDOT Drainage Manual Plate 3.19-4 45 1:1 . a 40 i O) ai 35 N 0 —12:1 aJ 0 30 ai rn --2:1ct 25 0.01 0.1 1.0 10.0 Mean Diameter, inches ANGLE OF REPOSE FOR RIPRAP STONES Source: VDOT Drainage Manual Plate 3.19-5 III - 181 I VJ o -I N n R 45 I I I O 45 Angle of Repose H 40 C7 — P. w 40 � 35 -. . cD —1.5 35 30 --- y ,�30 a a —2 L a a') 2 5 25- ,-4 -a a, — 2.5 00 0 20 N —3 20 a v •r v' 15 — `+- —4 0 a r 0 10 —6 =8 5 —10 ►d 0 0 0.2 0.4 0.6 - 0.8 1.0 0 K2 ,", RATIO OF CRITICAL SHEAR ON SIDES TO CRITICAL SHEAR ON BOTTOM C,, rn 1992 3.19 2.0 Bs = Surface Width Ro = Mean Radius of Bend 1.5 1.0 0 0.2 0.4 0.6 0.8 1.0 Bs/Ro RATIO OF MAXIMUM BOUNDARY SHEAR IN BENDS TO MAXIMUM BOTTOM SHEAR IN STRAIGHT REACHES Source: VDOT Drainage Manual Plate 349-7 III - 183 1992 3.19 APPENDIX 3.19-b RIPRAP DESIGN EQUATIONS FOR LAKES AND PONDS SUBJECT TO WAVE ACTION In many instances, riprap is installed along the shoreline of nontidal ponds and lakes in order to protect them from the continual scour of wind-driven waves. The following methods/equations will produce minimum design parameters for size of stone, depth of buried toe (or width of riprap apron) and height of structure above average water level. I. Size of Riprap Required-See VDOT Drainage Manual ("Design of Slope Protection to Resist Wave Action"). II. DWH (Design Wave Height) - See VDOT Drainage Manual ("Design of Slope Protection to Resist Wave Action") or U.S. Army Corps of Engineers' Shore Protection Manual. III. Depth of Buried Toe = DWH at design wind speed. IV. Width of Riprap Apron (Alternative to Buried Toe) = DWH x 2 V. Height of Structure (Above the Average Water Level) = DWH x 1.5 • III - 184 1992 3.29 STD & SPEC 3.29 o , SURFACE ROUGHENINGCI) Definition Providing a rough soil surface with horizontal depressions created by operating a tillage or other suitable implement on the contour, or by leaving slopes in a roughened condition by not fine-grading them. Purposes 1. To aid in establishment of vegetative cover with seed. 2. To reduce runoff velocity and increase infiltration. 3. To reduce erosion and provide for sediment trapping. '�.�?. ' ' -. ;��ti,. . .a„,4:^;, ,tr:. :w.f; : fir.F.u'"�.� ,,.::.1 OP "F. ;, 'yam.' , N S" ^wt A a" K �.1'77, R ka� •.; 'f '`''''1,;���4 . _ meµ°°.,\�,�;Y � �' �n"d)� ".' . ` Via S ,„ . s`' e r „k. s-. .v : ". ,,,� c-� ;'V M � ' +� s x ` " , ' „ ,t � .:„ N..a -• f . „ ,....a� �„ , # ,* ..:,...... i.,,,,41.1.,..?;.. .,:wrz.„‘,___: ._. „, 46eVt.„,-,,,,,4,,,,,,: , r,,,, ,� ,r �} i x"' �� " „ 7' !,1-" V.- '' fir ^ 3:1. �'' v.. '. ,,,," `�...�'� � ,* e � " Ems. ,�^ '� ° � .y� ' �,°`Y !4; X t, ?✓ .. r'^.,-,. �.. ski`' 1' r " .t T ,w�' '�" n,,:, r. ,i • �,.."` ,� r s"' • t% �+ r .. is r yx 2�`�" ,. �; "� a 1...+ ,,� . t' `�,� ,,x" are' g III - 273 1992 3.29 Conditions Where Practice Applies 1. All slopes steeper than 3:1 require surface roughening, either stair-step grading, grooving, furrowing, or tracking if they are to be stabilized with vegetation. 2. Areas with grades less steep than 3:1 should have the soil surface lightly roughened and loose to a depth of 2 to 4 inches prior to seeding. 3. Areas which have been graded and will not be stabilized immediately may be roughened to reduce runoff velocity until seeding takes place. 4. Slopes with a stable rock face do not require roughening or stabilization. Planning Considerations Graded areas with smooth, hard surfaces give a false impression of "finished grading" and a job well done. It is difficult to establish vegetation on such surfaces due to reduced water infiltration and the potential for erosion. Rough slope surfaces with uneven soil and rocks left in place may appear unattractive or unfinished at first,but encourage water infiltration, speed the establishment of vegetation, and decrease runoff velocity. Rough loose soil surfaces give lime, fertilizer and seed some natural coverage. Niches in the surface provide microclimates which generally provide a cooler and more favorable moisture level than hard flat surfaces; this aids seed germination. There are different methods for achieving a roughened soil surface on a slope, and the selection of an appropriate method depends upon the type of slope. Roughening methods include stair-step grading, grooving, and tracking. Factors to be considered in choosing a method are slope steepness, mowing requirements, and whether the slope is formed by cutting or filling. 1. Disturbed areas which will not require mowing may be stair-step graded, grooved, or left rough after filling. 2. Stair-step grading is particularly appropriate in soils containing large amounts of soft rock. Each "step" catches material which sloughs from above, and provides a level site where vegetation can become established. 3. Areas which will be mowed (these areas should have slopes less steep than 3:1) may have small furrows left by discing, harrowing, raking, or seed-planting machinery operated on the contour. 4. It is important to avoid excessive compacting of the soil surface when scarifying. Tracking with bulldozer treads is preferable to not roughening at all, but is not as III - 274 1992 3.29 effective as other forms of roughening, as the soil surface is severely compacted and runoff is increased. Specifications Cut Slope Applications For Areas Which Will Not Be Mowed Cut slopes with a gradient steeper than 3:1 shall be stair-step graded or grooved (Plates 3.29-1 and 3.29-2). 1. Stair-step grading may be carried out on any material soft enough to be ripped with a bulldozer. Slopes consisting of soft rock with some subsoil are particularly suited to stair-step grading. The ratio of the vertical cut distance to the horizontal distance shall be less than 1:1 and the horizontal portion of the "step" shall slope toward the vertical wall. Individual vertical cuts shall not be more than 30 inches on soft soil materials and not more than 40 inches in rocky materials. 2. Grooving consists of using machinery to create a series of ridges and depressions which run perpendicular to the slope (on the contour). Grooves may be made with any appropriate implement which can be safely operated on the slope and which will not cause undue compaction. Suggested implements include discs, tillers, spring harrows, and the teeth on a front-end loader bucket. Such grooves shall not be less than 3 inches deep nor further than 15 inches apart. Fill Slope Applications For Areas Which Will Not Be Mowed Fill slopes with a gradient steeper than 3:1 shall be grooved or allowed to remain rough as they are constructed. Method (1) or (2) below may be used. 1. Groove according to #2 above. 2. As lifts of the fill are constructed, soil and rock materials may be allowed to fall naturally onto the slope surface (see Plate 3.29-3). Colluvial materials (soil deposits at the base of slopes or from old stream beds) shall not be used in fills as they flow when saturated. At no time shall slopes be bladed or scraped to produce a smooth, hard surface. HI - 275 1992 3.29 Cuts. Fills, and Graded Areas Which Will Be Mowed Mowed slopes should not be steeper than 3:1. Excessive roughness is undesirable where mowing is planned. These areas may be roughened with shallow grooves such as remain after tilling, discing, harrowing, raking, or use of a cultipacker-seeder. The final pass of any such tillage implement shall be on the contour (perpendicular to the slope). Grooves formed by such implements shall be not less than 1-inch deep and not further than 12-inches apart. Fill slopes which are left rough as constructed may be smoothed with a dragline or pickchain to facilitate mowing. Roughening With Tracked Machinery (see Plate 3.29-4) Roughening with tracked machinery on clayey soils is not recommended unless no alternatives are available. Undue compaction of surface soil results from this practice. Sandy soils do not compact severely, and may be tracked. In no case is tracking as effective as the other roughening methods described. When tracking is the chosen surface roughening technique, it shall be done by operating tracked machinery up and down the slope to leave horizontal depressions in the soil. As few passes of the machinery should be made as possible to minimize compaction. Seeding Roughened areas shall be seeded and mulched as soon as possible to obtain optimum seed germination and seedling growth. III - 276 1992 3.29 STAIR STEPPING CUT SLOPES 1 DEBRIS FROM SLOPE ABOVE IS CAUGHT — — 1 11 I = BY STEPS-- 1/4 1=1 I I, 111- I-I 1=' 111= o _ oR�/NACE I=1 I I 0 ,11 ,.,�1111 III= I-1 I hi f_1.i. II 111- 1I 111I- -1 1 III II1 1I1 lI ' III- -III-11 40"-50" �. 11=1 11 I 1 I I,� IIII, 1'ii l 1111111; 1 I-1 1 1- WATER, SOIL AND FERTILIZER I I-1 1 1-1 11-1 1 1-1 1 1- ARE HELD BY STEPS - PLANTS -111—III-111-111_ CAN BECOME ESTABLISHED ON THE STEPS. Source: Va. DSWC Plate 3.29-1 GROOVING SLOPES !ICI H . , I , 1 , iiii iiii i i i i i i i i i I + I i I i—iil I 1 1 1-1 _ _ �tiill .i IIIIIIII1111111-11 1-( I I=1 I I- 4D -111 - III,�11I1=1 y./ „._ '" -111-11 --, - -I I I-I I I- %. ' ' i 11,;III _ GROOVING IS CUTTING FURROWS I-1 1-1 1 1— ALONG THE CONTOUR OF A SLOPE. II—111=IRREGULARITIES IN THE SOIL 111- - 111-1 - - SURFACE CATCH RAINWATER AND ' '—1 11_1 1 1_1 PROVIDE SOME COVERAGE OF LIME, FERTILIZER AND SEED. Source: Va. DSWC Plate 3.29-2 III - 277 1992 3.29 .4.� �.ilf tier' y�. ..,iri:i!' .., "--1, - !, lF" iF..-7,,n._ ...„,,_:......,:.„,,„„,4,.,_..74 ..A„_i.s.,.....,./,.-,.,. .• .4._,,, , ,,,,_ :.,. _ ,...„._. „A, .. ,q, 4 b... ."e`'''"• ---(mr ____________ „....„. ---.. .. ____-- ,...--0—e---...--" , EACH LIFT OF THE FILL IS COMPACTED, BUT THE OUTER FACE OF THE SLOPE IS ALLOWED TO REMAIN LOOSE SO THAT THE ROCKS, CLODS, ETC. REACH THE NATURAL ANGLE OF REPOSE. FILL SLOPE TREATMENT Source: Va. DSWC Plate 3.29-3 ,'0'1'111j \ 410‘1 4,--;-,,...,..,--1: -..„.., ..,....- _____ ,_.0 \:--zie,i::,,--;4,,,t,*.ii-4,,,,,, ,,, • r•i� ;• -�h--. ear\\\\+ / • ee... C ...,_....,,,,,<:;::;r60 libilkl' f.:"(40, ' .4*,-;*',w1,, ,...;-.4.--- JOU --„,,,,..--e-,...,-,:,, . . ram, �� ;,��;f.� a • • ----0A: SO" - __,,---- -•..."--4e-•0 ---‘," \ r. DOZER TREADS CREATE ` ,. '-•--.�� "- .0 '•,1*`�- GROOVES PERPENDICULAR ; , 4lf;* 'r•�* TO THE SLOPE. !' " f'. /, S�OQE � 'tom/ 44 e4�' At /4 TRA CKIN G Source: Michigan Soil Erosion and Sedimentation Guide Plate 3.29-4 III - 278 i APPENDIX J- Pollution Prevention Plan Training Log Date Parties in Attendance Pollution Prevention Items Discussed 38 .^