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HomeMy WebLinkAboutWPO202000033 Review Comments WPO VSMP 2020-08-21COUNTY 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: Malloy Ford —VSMP Project t"de#: WPO2020-00033 Plan prepares Shimp Engineering, 912 E. High St. Charlottesville, VA 22902 Kendra Patrick, kendra6dnshimo-engineering.com Justin M. Shimp, justin(i�shimy-engineering.com Owner or rep.: Malloy Properties III, c/o Malloy Companies LLC [ gmalloy2@aol.com ] 2070 Seminole Trail, Charlottesville, VA 22901 Plan received date: 10 Jun 2020 (Rev. 1) 19 Aug 2020 Date of comments: 24 Jul 2020 (Rev. 1) 21Aug 2020 Reviewer: John Anderson Cc: Christopher Perez, CDD /Planning 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 ESCP, (3) a SWMP, and (4) any TMDL measures necessary. A SWPPP was apparently not included with the Application. Provide SWPPP using county template. Include reference to WPO202000033 in SWPPP title. Link to template: httD://www.albemarle.ore/UDload/imaRes/fonns center/deoartments/Community Develonment/fonns/Enaineerine and WPO Forms/Stomrwater Pollution Prevention Plan SWPPP temolate.Ddf. Project is subject to VESCPNSMP since LOD =0.91 Ac., but does not require a VAR10 state permit, since LOD <1 Ac. (Rev. 1) Partially addressed. As follow-up: 1. Sec.I /Registration Statements Sec. LA.: List phone number for Geoff Malloy. 2. Sec.I /Registration Statements Sec. IV & Recommend revise estimated start date, now listed as 7/l/20. 3. Sec. 415: Please update these sections with ESC /SWM plans, since prior ESC/SWM-related comments are addressed. 4. Sec. 6.A./PPP Exhibit. Excellent. Please revise to show symbol for vehicle /equipment washing on Exhibit. 5. Sec. 6.E. (Individual with PPP oversight responsibility): Please list a named individual. 6. Sec. 7: Please revise to reference 2019 CGP Part II.G.2.A. inspection frequency; see p. 14, 2019 VPDES CGP Mink, below. (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. 7. Sec. 9: While Certification is signed, an individual is not listed. Please revise to list Malloy Properties III, LLC as company, and provide printed name of the individual who signed the certification. (possibly Geoff Malloy) Engineering Review Comments Page 2 of 5 8. Sec. 11, with next /final submittal, please include the 2019 CGP; link: httl)s://www.deg.virgini& gov/Portals/O/DEQ/ W ater/StorTnwaterManagement/CGP%20ADA/CGP2019. i)df?ver- 2019-05-06-131630-407 B. Stormwater Management Plan (SWMP) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is approved. 1. Revise plan to include reference to WP0202000033, (Rev.1) Addressed. 2. Label pre -development land use map, p. 5 talc. packet, consistent with HydroCad node labels, p. 6, for clarity ( 2S, 3S). (Rev. 1) Addressed. Applicant response (7/30/20 letter): `Drainage areas are shown on a separate map. The landuse information for each drainage area is in a summary table on C9.' 3. Note: Tables 1, 2, 3, included with 1-p. letter d. 6/5/20 addressed to `plan reviewer' are confusing. (Rev. 1) Comment withdrawn per phone conversation (07/28/20). 4. Notwithstanding detail on 08, provide pre -developed land cover (turf /impervious area) tables for areas within and outside LOD that drain to POA 1, 2. Similarly, on C9 (post -development) provide breakdown (Ac. /sq. ft.) of buildings, pavement, walkways, etc. to provide context for 0.08 Ac. decrease in impervious area and equal increase in managed turf in the post -developed condition, to aid evaluation of Tables 1, 2, 3 (6/5/20 letter), Area values are particularly important. It is unclear for the moment how calculations are derived, unclear how 0.08 Ac. transitions from pre -developed impervious to post -developed turf. It is unclear how energy balance values are derived. (Rev. 1) Addressed. Applicant response: `Landscape islands were added in the front of the site as well as within the site, which account for this 0.08 ac transition from pre -developed impervious to post -developed turf.' 5. Revise Calculation Packet for clarity: (Rev. 1) Addressed. a. Provide drainage maps/divides consistent with calculations /HydroCad routings, similar to C8, C9, with clarity the objective. Ensure consistency of graphic /mapped pre- /post -developed ground cover data with impervious /pervious values shown in HydrodCad input /output data values. (Rev. 1) Addressed. Applicant response: `Because of all the different drainage areas (inside LOD/outside LOD/POAI/POA2) it is challenging to also show land use on the same sheet. Separate landuse maps are included in the SWM calculations packet. Sheet C9 does include a table which summarizes the drainage area acreage and curve number, which is consistent with the values used for HydroCAD. Runoff volume data is an output from HydroCAD based on acreage, CN, TOC, and rainfall data. The runoff volume information can be found in the HydroCAD output data in the SWM calculations packet (bottom of page 8, for example).' b. Table 2 is perplexing. It is unclear how pre- /post -developed areas outside the LOD with identical Q1 values = 0.0 are subject to or influence compliance with 9VAC25-870-66. (Rev. 1) Addressed. Applicant response: `The zero "0" values have been changed to dashes "" to avoid confusion. There is no drainage area outside the LOD for POA2. c. It is unclear hoN� ively high impervious area (pre- /post -developed) complies with 9VAC25-870-66 tneig) vuiruice since C5 indicates connection to a manmade storm conveyance system, unless plan means to indicate compliance with 9VAC25-870-66.3 to avoid analysis to Limits of Analysis (9VAC25-870-66.4). Note: This plan proposes no detention. With precisely - drawn LOD, I.F. (energy balance) is 0.9 rather than 0.8, as would be the case with LOD >1 Ac. Additional calculation and graphic details are essential to aid review and understanding of compliance approach. (Rev. 1) Addressed. Applicant response: `Compliance is largely due to the decrease in impervious area from pre to post development, which is shown on the landuse maps in the SWM calculations packet. Additionally, a portion of the building pad draining to POA 1 is to remain undisturbed (gravel & asphalt will be laid on top of it) which allows the disturbed area to remain under 1 acre, requiring a less intensive improvement factor.' d. Show all calculations: (Rev. 1) Comment withdrawn per phone conversation (7/28/20). i. Table 1, 2 Ql [ see image, below] ii. Table 3, Ql Allowable iii. RV calculations Engineering Review Comments Page 3 of 5 6. C& Include VDOT typ. details for MIL inlets, MH steps, pipe bedding, inlet shaping, etc. (Rev. 1) Addressed. CT 7. LD-229 table caption reads Malloy Furniture Store. Plan title retains quality of an auto dealership. Please clarify. (Rev. 1) Addressed. 8. Show existing INV IN for Ex. storm pipe at Str. Al. (Rev.1) Addressed. 9. Provide Y:" steel plate in floor of Str. Al. Label profile to indicate steel plate is provided. (Rev. 1) Addressed. 10. 08, C9: Provide DA summary tables for C8 similar to DA summary tables shown on C9. Also, items 4, 5, above. (Rev. 1) Comment withdrawn. See tables on C9. 11. Additional comments possible. Table 1. Values for DAs Within LOD - Energy Balance Equation PREDEV POSTDEV POA Q1 RV RV 1 2.39 0.115 0.102 2 0.67 0.031 0.027 Table 2. Values for DAs Outside LOD — Energy Balance Equation PREDEV POSTDEV POA Q1 RV RV 1 1.63 0.088 0.088 2 0 0 0 C. 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 anproved. C3 1. Revise to indicate that portions of building shown as existing no longer exist. Ref satellite imagery, 6/26/20 [ next pg.]. Note: Building demolition does not appear to have disturbed areas within building envelope beneath slab. Note: Land disturbance requires a grading permit. (Rev. 1) Addressed. 2. Show existing tree line, if C4 proposed tree line differs. (Rev. 1) Addressed. 3. Provide TMP data for developed and adjacent properties (TMP #, owner name, deed bk.-pg.). (Rev. 1) Addressed. 4. C4: C6 detail for straw wattle does not indicate how this measure can be installed in locations shown, which include pavement. A filter cloth /stone filtering measure (VESCH) may be required for paved locations. Please ensure whatever measure is proposed is resistant to proposed construction activity and construction traffic. [Note: straw wattles do not appear to be a VESCH measure, utilize VESCH measures.] (Rev. 1) Addressed. Applicant response: `Acknowledged. Realistically, any E&SC measure in that location would need to be moved for a period of time for the asphalt to be cut up. Therefore, we are now specifying that silt fence be installed. The construction sequence details that the asphalt in the location of the silt fence be removed first and silt fence be immediately installed before more construction occurs." 5. C4: Show proposed tree line. (Rev. 1) Addressed. 6. C3 C4C4: Label all impervious surfaces: Ex. drive aisles, parking, building slab, etc. Identify curbing, walks, etc. to help visualize proposed ESC measures. Ref. 6/26/20 satellite image, below. (Rev. 1) Addressed. 7. Provide site layout sheet consistent with SDP202000039. Note: C5 may suffice if title is revised to: E&SC Plan Ph 2 - Site Layout. (Rev. 1) Addressed. C5: Engineering Review Comments Page 4 of 5 8. Site Layout sheet: (Rev. 1) Addressed. Applicant response: `Most of the existing travelway between Route 29 and the site is sloped towards a DI that exists in the median before Route 29. A small portion of the travelway between the medians is sloped towards Route 29 (note that VDOT built the road this way). However, because of the new landscape island in front of the site (in lieu of existing impervious surface for parking spaces) and the overall reduced drainage area to POA2, the volume of runoff to Route 29 is actually decreased. This is demonstrated by the energy balance equation calculations for POA2. Please let me know if a separate exhibit would be useful to demonstrate this point, I am happy to email /discuss." a. Include linework, notes, labels etc. that indicate limits of disturbance begin /end as shown on C4, C5 (`saw cut' `No soil disturbance' etc.) b. Include spot elevations that indicate direction of sheet or concentrated runoff, west to east, in the vicinity of Rt. 29. No additional storm runoff as surface runoff into U.S. Rt. 29 is permissible. 9. Ensure no site runoff enters U.S. Rt. 29. Provide RWD. (Rev. 1) Addressed. Applicant response: `A diversion dike is now provided on the entrance closest to Route 29 (the other two entrances are pitched to drain almost completely into the site). A DD was specified instead of RWD since this entrance is not supposed to be used as a construction entrance.' 10. Label existing storm pipe (material /DIA) that enters MH Str. Al. (Rev. 1) Addressed. 11. Evaluate condition of existing storm pipe from Str. Al to next downstream MH structure, or property line, whichever is more distant. Conditon of existing pipe must be rated by a qualified engineering professional to be satisfactory, requiring no repair (or repair or replacement must be complete), if it is to be relied upon for stormwater conveyance. Note listing date of visual inspection and identifying name of individual performing pipe evaluation must be included on the plan. (Rev. 1) Addressed. Applicant response (letter, 7/30/20): "Justin and I [ Kendra Patrick] visited the site on July 29, 2020 to inspect the ocndiitons of the existing storm system from Str. Al to the next manhole downstream. It had just rained the night before, so we were able to witness water flowing through both manholes and saw no need for repair. A note has been added to the plans on C5 regarding the date of /individual performing this inspection." Engineering Review Comments Page 5 of 5 D. Pollution Prevention Plan (PPP) The PPP content requirements can be found in County Code section 17-404. This PPP plan is disapproved, for single and minor reason provided below. a. With PPP (Sec. 6, SWPPP), provide 11" x 17" Exhibit that shows the following elements (at a minimum as needed): (Rev. 1) Partially addressed. As follow up: Please revise to show symbol for vehicle /equipment washing on Exhibit. 2. On -site lined containment for fuel, if on -site fuel storage proposed 3. Chemical /solvent storage, including concrete curing compounds 4. Portable sanitary facility (Porta-john) 5. Rain gauge 6. Concrete washout, draining to trapping measure 7. CE /PCE with wash rack, draining to containment (Rev. 1) Included with Legend and CE shown on exhibit, but request symbol for vehicle and equipment washing be shown graphically on the exhibit. 8. Non -hazardous solid waste dumpster ( with cover) 9. Include WP0202000033 on Exhibit The VSMP permit application and all plans may be resubmitted for approval when all comments have been satisfactorily addressed. For re -submittals, given pandemic, we encourage digital plan submittal since print submittals must be quarantined. Due to safety concerns, Engineering has discontinued plan review /comment meetings (24 PM on Thursdays) with the public, but CDD is gradually working toward at least partial re -opening to the public. 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 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 24 weeks to obtain all the correct signatures and forms. Stormwater Management Facilities Maintenance agreements will /may also need to be completed and recorded (if subsequent plan revisions propose stormwater detention, for example). 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 (as needed) are complete, if area of disturbance is less than 1 Acre ( 0.91 Ac. LOD proposed), then the County can hold a pre -construction conference. Applicant 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 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, htti)://www.albemarle.org/dei)tforms.asi)?department--cdengwpo WPO202000033 Malloy Ford VSMP 082120rev1.doc