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HomeMy WebLinkAboutWPO201900039 Review Comments WPO VSMP 2019-10-18COUNTY OF ALBEMARLE Department of Community Development 401 McIntire Road, Room 227 Charlottesville, Virginia 22902-4596 Phone (434) 296-5832 Fax (434) 972-4126 VSMP Permit Plan Review Project title: Hillcrest Vineyard Tasting Room & Venue Project file number: WP02019-00039 Plan preparer: Monteverde Engineering & Design Studio [sroderick(&MonteverdeDesi ne s.coml Owner or rep.: Augusta Professional Park, LLC Plan received date: 21 June 2019 (Rev. 1) 16 August 2019 (Rev. 2) 20 Sep 2019 Date of comments: 17 July 2019 (Rev. 1) 27 August 2019 (Rev. 2) 18 October 2019 Reviewer: (Initial /Rev. 1) WW Associates, Inc. Reviewer: (Rev. 2) J. Anderson Note: If text grayscale, comment was addressed with Rev. 2. Other comments are insufficiently addressed /not addressed, persist, or require follow-up. New comments based on Rev. 2 require design revision. Comment response letter is helpful. Digital submittal is welcome and will be placed in review queue. Engineering will make effort to review revised plans within 15 business days. Alternatively, submit revised print plans (2 copies) for review. Engineering encourages a review meeting, which may be helpful. County Code section 17-410 and Virginia Code §62.1-44.15:34 requires the VSMP authority to act on any VSMP permit by issuing a project approval or denial. This project is denied for reasons listed, below. The VSMP application content requirements can be found in County Code section 17-401. A. Stormwater Pollution Prevention Plan (SWPPP) The SWPPP content requirements can be found in County Code section 17-405. A SWPPP must contain (1) a PPP, (2) an ESOP, (3) a SWMP, and (4) any TMDL measures necessary. 1. Please revise the title to "Hillcrest Vineyard Tasting Room & Venue VSMP" on the cover sheet of the stormwater management calculations. 2. Please add WP02019-00039 to the cover sheet of the stormwater management calculations. 3. Section 2 — Please provide a copy of the DEQ coverage letter when obtained. (Rev. 2) Persists. 4. Section 3 — Please complete the areas indicated for the proposed improvements. 5. Section 4 — Please provide an 11"x17" copy of the latest E&SC Plans 6. Section 5 — Please provide an 11"x17" copy of the latest SWM Plans. 7. Section 9 — Please complete and sign the certification. (Rev. 2) Addressed. Applicant response (9/19/19 letter): `Certification has been completed and signed.' Signed /dated PE -seal is unconventional, but acceptable. 8. Seetion — Per 9VAC25-880-70 Part K, please provide the person with the authority to sign inspection reports or to modify the stormwater pollution prevention plan. (Rev. 2) Addressed. 8-2-2019 SWPPP provides name of individual with authority to sign inspection reports (this is Sec. 8); Sec. 10, Delegation of Authority form, is not required to be complete at this time. 9. Provide a site -specific mitigation plan for the disturbance within the stream buffer. Include the embankment disturbance resulting from road grading. The plan must address native plants, if any, existing Engineering Review Comments Page 2 of 7 within the buffer zone (County Code 17-601D). (Rev. 2) Partially addressed. As follow-up: Ref. email sent 10/18/2019 12:11 PM. 10. Provide a drawing that shows the planting plan, zones and proposed mitigation area(s). (Rev. 2) Partially addressed. Asfollow-up: Ref. email sent 10/18/2019 12:11 PM. 11. Provide calculations for mitigation areas and disturbed areas. 12. Delineate forest and open areas, show them on a drawing and describe them in the narrative. 13. Provide professional's seal on Stream Mitigation Plan. 14. Revise first paragraph of Mitigation Plan to cite Albemarle County Code (currently cites City of Charlottesville Code). (Rev. 1) NA. Applicant response: `Buffer Mitigation document has been removed from submittal package.' 15. Please note that additional comments may be generated based on responses to these comments. 16. New: a. Include 2019 VPDES Registration Statement (ensure form accurate /complete); link: hiip://www.albemarte.orgLupload/ima2es/forms_center/departments/Community Development/forms/Engine erine and _WPO_Forms/CGP_ Registration _ Statement _2019_FINAL _201904.pdf b. Update Secs. 4-5 of SWPPP, once comments addressed. c. Insert PPP at proper location, which is Sec. 6.A. d. Insert copy 2019 VAR10 (this is a 26-pg. template document); link to 2019 DEQ CGP (VAR10): hqp://www.albemarle.org/upload/imai4es/forms center/departments/Community Development/forms/Engine ering and WPO Forms/CGP 2019.pdf e. Include 2019 Notice of Termination in SWPPP (insert at /with VAR10); link to form: hqp://www.albemarte.or¢Lupload/ima2es/forms center/departments/Community Development/forms/Engine ering and _WPO_Forms%CGP Notice of Termination _2019_FINAL _201904.pdf B. Pollution Prevention Plan (PPP) The PPP content requirements can be found in County Code section 17-404. 1. The PPP exhibit must be included in the SWPPP. (Rev. 2) As follow-up: Ref. item 16.c., above. C. Stormwater Management Plan (SWMP) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is disapproved, and the reasons are provided in the comments below. The stormwater management plan content requirements can be found in County Code section 17-403. 1. The plan proposes the use of conserved open space to address the water quality for the proposed improvements. Conserved open space shall be protected by a perpetual easement, deed restriction, or other mechanism enforceable by the VSMP Authority that assigns a responsible party to ensure that no future development, disturbance or clearing may occur within the area, except as stipulated in the vegetation maintenance plan. Please provide documentation to this affect with the final plan. (Rev. 2) Partially addressed. As follow-up: Ref email sent 10/18/2019 12:11 PM. Also, Applicant response: `An easement for conserved forest and open space will be provided upon completion of plan review process. The owner and surveyor will provide the plat for the easement.' Engineering requests easement plat application showing 26.00 Ac. forest /open space easement, consistent with VaRRM.xIs spreadsheet, as soon as possible. An easement plat, if required for compliance (as is the case, here), must be recorded prior to VSMP /WPO plan final approval. A Grading Permit will not be issued prior to final VSMP plan approval. Note: Easement plats require deeds, as well. 2. Provide details and supporting calculations for the measures that will be utilized to convert the concentrated flows leaving the site to sheet flow. (Rev. 2) Partially addressed. Applicant response: `Level spreaders are provided to distribute stormwater runoff into sheet flow. Calculations have been provided for size/length of each level spreader.' As follow-up: a. Please direct /advise reviewer of LS 1 location (plan sheet, and relative to site). b. LS in this application is a stormwater management device used to convert concentrated to sheet Engineering Review Comments Page 3 of 7 flow. It is not a temporary ESC measure. VESCH, 3rd Edit., 1992 includes Level Spreader, Std & Spec 3.21, with text (where practice applies) stating: `Where there is a need to divert stormwater away from disturbed areas to avoid overstressing erosion control measures; where sediment -free storm runoff can be released in sheet flow down a stabilized slope without causing erosion.' This handbook was published prior to existence of 1999 Virginia Stormwater Management Handbook, and well prior to development of 2011 Virginia Stormwater Best Management Practices. These later stormwater design resources are primary. Unless VSMH or DEQ BMPs explicitly reference Std & Spec 3.21 (they do not), Albemarle cannot accept a temporary ESC standard for permanent level spreaders. Use design criteria published at VA DEQ Spec. No. 2, Table 2.2. For SWM plans that rely on level spreader/s (LS) to convert concentrated storm runoff to sheet flow, Table 2_2 specifies LS length requirements. Revise design per Table 2.2 (LS) criteria. Length (LS2) for Qio=8.923cfs, is 116'. c. Provide Calculations Report index or TOC to correlate a specific hydrograph to LS1, LS2. d. Provide calculations for each level spreader: LS1, LS2 —calculations do not appear to be included in Cale. Report. Ref. Table 2.2 when providing calculations. Also, see item b., above. e. Revisiting initial comment (`Provide details and supporting calculations for the measures that will be utilized to convert the concentrated flows leaving the site to sheet flow'): i. Revisit gravel filter diaphragm design for parking lot: 1. At certain locations, runoff is parallel to diaphragm; revise design at these locations 2. Near tasting room /venue building, runoff will likely exit paved surface at a single point, not as sheet flow. Provide level spreader at this location. Note: gravel filter diaphragm /level spreader /parking lot grades /9VAC25-870-66.D. reviewed with County Engineer. We recommend meeting 24-Oct, if possible, to review proposed design, and design approach. ii. Ditches exist wherever existing /proposed grades alongside site access road form a `V' or valley. Ditches concentrate flow. Concentrated flow must be converted to sheet flow, or be discharged to a natural or manmade channel. Concentrated flow may not release to terrain with no defined channel, as concentrated runoff may cause erosion. This is true even if a farm or SWM pond is downslope of proposed ditches /concentrated flow. 3. Provide a gravel diaphragm or other pretreatment measures for areas where sheet flow is discharging to the conserved open space. 4. Label and provide drainage area maps and calculations for the proposed stormwater conveyance channels. (Rev. 2) Partially addressed. Applicant response: `Stormwater drainage areas are labeled on sheet C-6.02, capacity calculations are included in the storm calculations package.' As follow-up: Channel Calculations table in Cale. Report list values; for example: slope, width, depth, Qio, Qio Vel. a. Please provide calculations that support these values. b. Show /provide roof leader line point of discharge (downspouts convey stormwater). c. Provide adequate stormwater quantity control measures for roof leader line discharge point/s. 5. Label completely and provide drainage area maps and calculations for all proposed culverts. (Rev. 2) Partially addressed. Applicant response: `Stormwater culvert drainage areas are labeled on sheet C-6.02, and capacity calculations are included in the storm calculations package.' Asefollow-up: Unless mistaken, Cale. Report table titled Existing Storm Drain Analysis 10 yr does not compare proposed Qio volume with Qio capacity of proposed culvert pipes. a. Provide VDOT LD-229, storm sewer design computations, for proposed storm pipes. b. Provide profiles for proposed storm pipes: Label pipe material type, length, DIA, and slope. c. In plan view, C-6.03, recommend remove 15in-SD (within line -type visible only at extreme magnification), and provide labels that identify 15" DIA. d. If structures 1 — 4 are proposed new structures, revise table heading to remove ref. to `Existing.' 6. Please show the drainage divides and associated areas for all drainage areas shown on the drainage area maps. (Rev. 2) Partially addressed. Applicant response: `Drainage areas and divides are shown and Engineering Review Comments Page 4 of 7 labeled on sheet C-6.02.' As follow-up: Revise one of two DA-4s to read DA-3. 7. Include access road and pond embankment areas in the drainage areas. 8. Provide calculations for concentrated flow channels. (Rev. 2) Withdrawn. Covered elsewhere. 9. Show how concentrated flow discharges from road ditches will be addressed. (Rev. 2) Not addressed. Applicant response: `Road ditches removed upon discussion with county staff. Stormwater will sheet across the access road and will not be concentrated. Owner understands the operation and maintenance implications of this design decision.' Asfollow-up: Design concentrates in ditches wherever proposed and existing grades form a `V' or valley. Proposed grading creates roadside ditches. Also: Hillcrest access drive typical section (C-9.01) includes a ditch. 10. The drainage area to the sedimentation basin is shown on Sheet C-301A, but the area (size) is not provided. This area must match the area used in the sedimentation basin calculation. (Rev. 1) Partially addressed. Applicant response: `Sediment basin drainage area and size is shown on sheet C-3.01-A and coordinated with calculations. Sediment basin dimensions added to sheet C-3.01-A.' As follow-up_ a. Revise C-3.01-A Temporary Sediment Basin Sizing Table to include Vol. (yd3) provided. Table lists only required wet and dry volume. b. Label SB floor dimensions in plan view, as this is a critical construction /inspection dimension. c. C-9.02: Sediment Basin Schematic Elevations do not list any elevations. Provide elevations on this profile (basin floor, cleanout elevation, dewatering device invert, rim, emergency spillway, crest). 11. Provide labels on the drainage area maps matching the area labels on the stormwater calculations. (Rev. 2) Not addressed. Applicant response: `Drainage areas are labeled on sheet C-6.02.' As follow-up: Please consider initial comment, and provide and correlate calculations with drainage area maps. 12. Show a total drainage areas to the Phase 2 level spreaders on the plan. 13. Provide time of concentration calculations for the drainage areas and show the flow path on the drainage area maps. If flow path is provided, please label legibly. (Rev. 2) Partially addressed. Applicant response: `Flow paths are shown and labeled on sheet C-6.04. Time of concentration calculations are computed through the watershed lag method included in the Hydroflow Program and are included in the stormwater calculations.' Asfollow-up: Tc included with Calc. Report, but flow paths are not shown or labeled on C-6.04. 14. Grouting solid the 18-inch CMP at the pond dam embankment if it is not to be used, to prevent future collapse. 15. Provide the Albemarle County General Construction Notes on the SMP. (Rev. 2) As follow-up: Ref. New, item 22.1 below. 16. Provide a detail for the gravel filter strip. 17. Label the stormwater ponds on the plans to match the calculations. Applicant response: `Stormwater pond is labeled as "Existing Pond" on all sheets on which it is depicted.' 18. Provide a BMP analysis for pre- and post -development, and show/define the areas on the map to match the VRRM spreadsheet. Applicant response: `This project is developed on a "greenfield" site; no BMPs are present on site. Water quality requirements are being met through dedicating 26.00 Ac. protected forest/open space.' Albemarle accepts this response. 19. On Sheet C-6.01, remove the drainage area label for "Post South" drainage area 89.26 ac. and make the D.A. labels more legible. Applicant response: `Drainage area Post South note removed from C-6.0L' 20. Please revise sedimentation basin calculations using a CN number for bare earth. The sedimentation basin design may have to be revised accordingly. 21. Please note that additional comments may be generated based on responses to these comments. New: 22. Since enlarged pond is utilized for SWM water quantity control, it is not strictly a farm pond, but requires SWM facility easement as well as geotechnical information and construction reports consistent with General Construction Notes for Stormwater Management Plans (see C-6.03). Please provide relevant documents prior to plan approval. Please provide easement for farm pond and level spreaders. Engineering Review Comments Page 5 of 7 GENERAL CONSTRUCTION NOTES FOR STORMWATER MANAGEMENT PLANS 1. ALL DAMS AND CONSTRUCTED FILL TO BE WITHIN 95% OF MAXIMUM DRY DENSITY AND 2% OF OPTIMUM MOISTURE CONTENT. ALL FILL MATERIAL TO BE APPROVED BY A GEOTECHNICAL ENGINEER. A GEOTECHNICAL ENGINEER IS TO BE PRESENT DURING CONSTRUCTION OF DAMS. 2. PIPE AND RISER JOINTS ARE TO BE WATERTIGHT WITHIN STORMWATER MANAGEMENT FACILITIES. 3. FOR TEMPORARY SEDIMENT TRAPS OR BASINS WHICH ARE TO BE CONVERTED TO PERMANENT STORMWATER MANAGEMENT FACILITIES; CONVERSION IS NOT TO TAKE PLACE UNTIL THE SITE IS STABILIZED, AND PERMISSION HAS BEEN OBTAINED FROM THE COUNTY EROSION CONTROL INSPECTOR. 23. C-6.03: Revise labels to read `Forest /Open Space Easement' rather than `Wooded/Open Space Easement.' 24. C-6.04: Sheet C6.05 Note states: `Existing Conditions: The owner of the parcel has built a new dam to enlarge the pond for agricultural purposes.' Revise text on C-6.04 to remove any reference to ED Pond, since our understanding is that a pond was enlarged for agricultural purposes. This farm pond was not, to our knowledge, constructed to VA DEQ Stormwater Design Specification No. 15. Reference to ED Pond may be misleading. The plan proposes an existing enlarged agricultural pond as SWM facility that will provide quantity control, whatever other agricultural purpose it serves. This pond is not proposed to provide quality /phosphorus reduction. Rather, 26.00 Ac. in forest /open space easement provides required phosphorus reduction. 25. C-9.01: Revise labels on Gravel Diaphragm with Thickened Asphalt Edge detail to reference `site layout /C-4.01,' not `site plan.' There is no site plan for this development. 26. C-605 (Mitigation Plan): a. Label Dick Woods Road. b. Provide additional Ex. contour labels. c. Reduce text pitch of Note -Labels to obscure as little underlying information as possible (Replant Zone 2, Replant Zone 3, All Native Plants, etc). d. All proposed grading downslope of dam must tie to existing contours. At elevations lower than 842', they do not. 27. Energy balance: Although e-mail with revised energy balance values was sent to reviewer 10/18/2019 11:27 AM, items persist. Correlate plans, Calc. Report hydrographs, and energy balance values to one another as clearly as possible. Make explicit correlations that are easy to understand. Items. a. SWM Water Quantity Energy Balance Worksheet included with Calc. Report d. Sept 19, 2019 includes: channel protection tables with apparent incorrect values (difficult to correlate); reasonable RVPost value; no RVPre value; and inaccurate Q values (from prior routings). This worksheet also included a 4-row table comparing Q allowable and Q Post development. Worksheet sent with email on 10/18/19 deletes the 4-row table. Restore 4-row table. b. Revise RVPre /RVPost values on worksheet sent with email 10/18/19, which are incorrect. c. Provide pre -development 1, 2, 10-yr hydrographs, as none appear to be included with Calc. report. d. Flood Control —Provide pre -development Q2no hydrograph routings. e. Present all terms in format that matches 9VAC25-870-66.B.3 (present calculations, or direct reviewer to plan sheet or Calc. Report location of Energy Balance calculations): Engineering Review Comments Page 6 of 7 a. In accordance with the following methodology: QDeveloped�I'F' (Pre -developed RVPre-Developed)/RVDeveloped Under no condition shall ODevelo,ed be greater than Opre-Developed nor shall OD, I,,d be required to be less than that calculated in the equation QForesr * RVForesYRvDeveioPed; where I.F. (Improvement Factor) equals 0.8 for sites > 1 acre or 0.9 for sites < 1 acre. QD,Ie ped - The allowable peak flow rate of runoff from the developed site. RVDeveIoped = The volume of runoff from the site in the developed condition. QPre-Developed - The peak flow rate of runoff from the site in the pre -developed condition. RVPre-Developed - The volume of runoff from the site in pre -developed condition. OForest = The peak flow rate of runoff from the site in a forested condition. RVFOCP,t - The volume of runoff from the site in a forested condition; or D. Erosion and Sediment Control Plan (ESCP) Virginia Code §62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESCP. This plan is disapproved for reasons listed below. The erosion control plan content requirements can be found in County Code section 17-402. 1. Show the existing topo within the limits of survey indicated on the plans, including the access road and pond embankment. If present, the existing topo lines are faint and illegible. 2. Show the grading for the entire proposed access road on the plans, including the pond dam embankment crossing. 3. Show the proposed site grading on dwg. C3.OIA. See E&S comment #1. (Rev. 2) Withdrawn. Applicant response: `Proposed site grading is shown on ESC plans C-3.02-A, B, C. Please be aware that C-3.O1A (Phase 1) is the ESC plan for work prior to mass cut/fill operations.' We appreciate this clarification. 4. A waiver is required for the proposed disturbance within the critical slope areas. Please provide evidence that a waiver has been obtained for this disturbance. (Rev. 2) Withdrawn. Applicant response: `The minimal grading into critical slopes for this project has been discussed and approved by Albemarle County Department of Community Development for this project per correspondence dated 9-13-19.' 5. Please show E&S protections required for all phases of construction of the pond spillway. 6. Show the tie-in of riprap below the proposed spillway to the existing grade. (Rev. 2) Partially addressed. As follow-up: See SWM Plan comment, New item 26.d., above. 7. The grading provided overlaps/conflicts with the sedimentation basin grading. Please correct. 8. Grade lines do not appear to be connected to existing contours. If present, please make them legible. 9. Please make all details on the detail sheets legible. The prints on many are faint and illegible. 10. Please note that additional comments may be generated based on responses to these comments. The VSMP permit application and all plans may be resubmitted for approval when all comments have been satisfactorily addressed. For re -submittals please provide 2 copies of the complete permit package with a completed application form. Engineering plan review staff are available from 2-4 PM on Thursdays, should you require a meeting to discuss this review. Process: After approval, plans will need to be bonded. The bonding process is begun by submitting a bond estimate request form and fee to the Department of Community Development. One of the plan reviewers will prepare estimates and Engineering Review Comments Page 7 of 7 check parcel and easement information based on the approved plans. The County's Management Analyst will prepare bond agreement forms, which will need to be completed by the owner and submitted along with cash, certificates or sureties for the amounts specified. The agreements will need to be approved and signed by the County Attorney and County Engineer. This may take 2-4 weeks to obtain all the correct signatures and forms. Stormwater Management Facilities Maintenance agreements will also need to be completed and recorded. The County's Management Analyst or other staff will prepare the forms and check for ownership and signature information. The completed forms will need to be submitted along with court recording fees. After bonding and agreements are complete, county staff will need to enter project information in a DEQ database for state application processing. DEQ will review the application information based on local VSMP authority approval. At this time, the DEQ portion of the application fees will need to be paid directly to the state. For fastest processing, this is done electronically with the emails provided on the application. DEQ should notify applicants with instructions on how to pay fees. When DEQ approves the application, they will issue a permit coverage letter. This should be copied to the county. After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction conference. Applicants will need to complete the request for a pre -construction conference form, and pay the remainder of the application fee. The form identifies the contractor and responsible land disturber, and the fee remaining to be paid. This will be checked by county staff, and upon approval, a pre -construction conference will be scheduled with the County inspector. At the pre -construction conference, should everything proceed satisfactorily, a joint VSMP and grading permit will be issued by the County so that work may begin. County forms can be found on the county website forms center under engineering; htt2://www.albemarle.org/deptforms.asp?department--cdengMo WP0201900039 Hillcrest Vineyard Tasting Room and Venue 101819rev2