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HomeMy WebLinkAboutWPO202000058 Review Comments WPO VSMP 2021-03-16V 401 McIntire Road, North Wing County of Albemarle Charlottesville, VA 22902-4579 COMMUNITY DEVELOPMENT DEPARTMENT Telephone:434-296-5832 WWW.ALBEMARLE.ORG VSMP Permit Plan Review Project title: VSMP Plan for Albemarle Business Campus Project Tile number: WPO202000058 Plan preparer: Keane Rucker, Shimp Engineering [ keane(a_shimp-en ing eering.com ] Owner or rep.: Fifth Street Forest, LLC / 250 W. Main St. Suite 201, Charlottesville, VA 22902 KyIe.redmger(d,)9mmI.com Plan received date: 23 Dec 2020 (Rev. 1) 3 Feb 2021 (Rev. 2) 5 Mar 2021 Date of comments: 8 Jan 2021 (Rev. 1) 1Mar 2021 (Rev. 2) 16 Mar 2021 Reviewer: John Anderson 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 outlined in email sent 3/16/2021 11:18 AM. Once 3/16/21 email comments are addressed and SWPPP is received, reviewed, and approved, this WPO plan can be approved. All Sec. C./D. SWMP /ESOP review comments addressed with Rev. 2. Email review comments sent 3/16/2021 11:18 AM comprise new follow-up review comments. 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. Also, please see email sent 2/26/2021 5:24 PM. 1. Submit SWPPP ( please use 12-section county template, link: httos://www.albemarle.org/home/showpublisheddocument?id=166 ). Additional comments possible. (Rev. 1) Partially addressed. Please submit WPO201800044-Amendment 1 Application, with revised SWPPP. Please check Sec. IIC Acreage values. Recommend revise completion date (each WPO) to allow flexibility since VAR10 CGP is valid thru 6/30/2024. (Rev. 2) Addressed. WPO2018-00044 Amendment #1 is under review. WPO2018-00044 Amend # 1 review comments sent as email, 3/16/2021 7:08 PM. 2. Use new DEQ Registration Statement (SWPPP, Sec. 1, Eff. 1/l/21), which requires off -site export (fill volume/type/destination) export be listed, to be tracked by local administrators (county), and reported monthly to DEQ. (Attached.) It appears this site may require net import. (Rev. 1) Addressed. As follow- up: Please ensure each VAR10 CGP registration statement corresponds with WPO201800044-Amendment 1 (ABC Phase 2), or WPO202000058 (ABC, phase 1,3,4,5). (Rev. 2) Persists. 3. Note: Applicant need not furnish fill export data (Registration Statement, SWPPP, Sec. 1), or SWPPP Sec. 6.E. /8. Information until just prior to pre -construction, in other words, plan may be approved without this information, but this information is required to apply for VAR10 /state permit, just prior to preconstruction. [ Sec. 6.E., named individual responsible for PPP measures; Sec. 8., named SWPPP inspector.] (Rev. 1) Addressed, Tim McGuan, Sr. Project Mgr. /EDC, Midlothian VA New 4. Please complete SWPPP Registration Statement Sec. III for WPO201800044, since ABC Phase 2 will export excavated material to ABC Phase 1,3,4,5. (Rev. 2) Persists. Ref. WPO2018-00044 Amend #1 review comments sent as email, 3/16/2021 7:08 PM. See email item 15 and second sentence. Engineering Review Comments Page 2 of 8 5. If Calculation packet is included with SWPPP, please ensure packet for ABC Phase 2 is included with WP0201800044 Amendment 1 SWPPP, and Calc. packet for ABC Phase 1,3,4,5 (p. 30, SWPPP) identifies WP0202000058, makes reference to ABC Phase 1,3,4,5, and clear ref. to ABC Phase 2 as not included. (Rev. 2) Withdrawn. See email sent, 3/16/2021 7:08 PM, review item 4. C 10 of WP02018-00044 provides sufficient SWM plan calculation for Mass Grade site. B. Pollution Prevention Plan (PPP) Also, please see email sent 2/26/2021 5:24 PM. The PPP content requirements can be found in County Code section 17-404. 1. Provide PPP Exhibit (SWPPP Sec. 6A) that identifies preliminary location of: (Rev. 1) Partially addressed. As follow-ua: Transfer ABC Phase 2 PPP Exhibit to WP0201800044 Amendment 1 SWPPP. Please provide WPO202000058 PPP Exhibit for all phases of ESC plan (IA, 113, 2, 3 [not all PPP measures may be needed for all phases]). Note: All measures are provided for WP0202000058, for a single phase of the ESC plan. Please ensure PPP exhibits are consistent with most recent revisions to ESC plan sheets. (Rev. 2) Persists. Engineering cannot locate SWPPP with Rev. 2 digital submittal. a. Rain gauge b. Portable sanitary facilities c. Covered non -hazardous solid waste dumpster d. Concrete wash -out draining to trapping device e. Paved construction entrance w/ spray wash f. Paint /Stucco /Solvent storage g. Lined (10rd) on -site fuel storage containment sized for fuel volume + 10-yr storm event x 1.1 C. Stormwater Management Plan (SWMP) Also, please see email sent 2/26/2021 5:24 PM. VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is disapproved for relatively minor (or text edit) items listed in email sent 3/16/2021 11:18 AM. Note: Albemarle Business Campus Topographic Pond Drainage Map and SWM Comparison: SDP2001-00129 Pond/Sewer design limits vs. ABC Achieved Conditions (table) talc. packet d. 12/23/20 are adequate to show compliance with 9VAC25-870-96 (water quality) and 9VAC25-870-97 (steam channel erosion). Also: see WP0201800044 (Royal Fern, VSMP) and WP0201800084 (Royal Fern, Phase 2). Note: Calculation packet, 12/23/20, is approved. [As favor. please include ref. to WP0202000058 on packet title pg.] Primary requests: WP02018-00044 Amendment #1 is under review, comments sent as email, 3/16/2021 7:08 PM 1. SWM design for (SDP2020-00066) ABC phase 2: SWM for this area was initially approved for a single- family layout (10 lots, WP0201800044: biofifter + FOS easement, C3, image, lastpg.), that approved WPO design is not shown with current WPO. In fact, WPO titled Albemarle Business Campus excludes ABC Phase 2, altogether, and does not portray any SWM or ESC for ABC Phase 2. Runoff from this area does not reach the SWM pond at Fifth Street Place* nor is Phase 2 included with areas anticipated to route to the SWM pond under C 10 exhibit, Sterling University Housing. This (or subsequent) WPO plan must provide SWM for ABC Phase 2 prior to SDP202000066 conditional initial site plan approval. The approved WPO (WP0201800044, Royal Fern VSMP) presents a different layout for area labeled AC Phase 2 (sheet CT now, apartments, then, single-family). WP0201800044 shows a Level 1 biofilter and several forest /open space easement areas, while the current WPO for ABC does not portray this area at all. Engineering welcomes telecon in interest of expedited revision /review. (Rev. 1) Persists. Applicant response (2/2/21 letter): `SWM design for ABC Phase 2 (Block 1) —since this is mass grading only, and will be allowed to return to natural open space condition, and since grading will not alter the runoff characteristics, no additional SWM design is required at this time. If/when this plan is revised in the future, it will be included in either a VSMP plan Amendment or occur under a separate permit with a different WPO application, depending on the developer's scheduling, which is not set at this point.' Clarification: 1) Phase 2 is new development (with ABC) originally approved as an alternate design for single-family 2) 3) 4) Engineering Review Comments Page 3 of 8 development (10 lots) under WP0201800044, approved 12/13/2018, a plan titled Royal Fern Phase I. Royal Fern Phase I was approved under technical criteria IIB, 9VAC25-870-65 /-66, stormwater quality and stormwater quantity standards that became effective 7/l/2014. Now, ABC Phase 2 replaces the approved Royal Fern Phase I design, while providing response above: Mass grading only, graded space to return to natural open space, no alteration of runoff characteristics, no additional SWM design required at this time. ABC Phase 2 site is currently forest. Clearing forest allowing `return to natural open space condition,' alters runoff characteristics. Grading —4.50 Ac. (WP0201800044), ref. image. 5) Application for the single-family subdivision development approved with WP0201800044 included criteria IIB VRRM.xls New Development worksheet post -developed land cover acreage values which calculate a required 1.58 lb. phosphorus reduction requirement. Values shown in image, bele are identical with approved calculations for Royal Fern Phase 1 /ABC Phase 2. [ Image removed with Rev. 2 comments.] 6) Applicant, with SDP202000066, proposes alternate design (ABC, Phase 2) that shows apartment buildings, parking, walks, underground detention for SWM, but abandons approved SWM design sufficient for the 10-lot single-family development. Several options are available to meet SWM requirements for this alternate design: (i) Remove ABC Phase 2 from both WP0202000058 and from FSP, such that no development or alteration of ABC Phase 2 site landscape is proposed with ABC FSP, or with WP0202000058, meaning, show only ABC, Phase 1, 3, 4, 5 with WP0202000058 and the FSP. This is an easier and quicker path to WPO plan approval. Applicant comment response appears to indicate interest in clearing the ABC Phase 2 site, but this is not possible without amending WP02018-00044 to indicate 4.50 Ac. (ABC Phase 2) forest converted to cleared condition. (ii) Retain ABC Phase 2 Mass Grading. Options: 1. Mass grade entire site (4.50 Ac.): a. B Soil /managed turf b. 021 Ib./yr, hos horns reduction (VRRM.xls snippet, below) c. rchase nutrient credits to receive a Grading Permit, more, below. (Rev. 2) Addressed. Nutrient purchase documents approved 3/16/21. 2. Project mix of post -developed land cover similar to that approved with WP0201800044 that anticipates likely mix of impervious /managed /FOS easement. Project into future, amend WP0201800044 based on projection. Meet phosphorus reduction requirement with nutrient purchase, or via combined off -site nutrient purchase /platted FOS easement /on -site BMP SWM control (specific to projected development) strategy. a. Purchase nutrient credits for ABC Phase 2 prior to Mass Grading. b. Coordinate purchase with Ana Kilmer. Ms. Kilmer must review draft bill of sale /Affidavit prior to purchase, for quickest nutrient purchase approval, and Grading Permit issuance (Rev. 2) Addressed. Nutrient purchase documents approved 3/16/21, 0.21 lb. c. Purchase credits prior to receiving a Grading Permit for ABC, any phase (1,2,3,4,5). (Rev. 2) Addressed. 3. Mass grade up to 3.97 Ac. of 4.50 Ac. ABC Phase 2 site. (Rev. 2) NA —FOS easement not required. Applicant purchased 0.21 lb. nutrient credits, purchase documents approved 3/16/21. Engineering Review Comments Page 4 of 8 a. Place 0.53 Ac. of 4.50 Ac. ABC Phase 2 site in forest -open space easement: i. Submit separate Easement Plat application. Easement plat review /approval /recordation required prior to WPO201800044 Amendment 1 approval. WPO202000058/WPO201800044 Amendment 1 approval required prior to ABC Phase 1,2,3,4,5 FSP approval. Note: Easement requires separate application, review fee/s, plat review, deed, deed /easement recordation. ii. 0.53 Ac. in FOS Easement calculates a 0.00 lb./yr, phosphorus reduction requirement for mostly mass -graded (3.97 Ac.) 4.5 Ac. (total) ABC Phase 2 site. Two hypotheticals [ Images removed with Rev. 2 comments.] 0.53 Ac. FOS (ABC, Phase 2 /Amend WPO201800044): 0.0 lb./yr. phosphorus reduction required. 0.00 Ac. FOS/4.50 Ac. managed turf: 0.21 lb./yr. phosphorus reduction required. 7) Engineering supports expedited review. Also, please see email sent 2/26/2021 5:24 PM. 8) Ref. ISP SDP202000066, Albemarle Business Campus, approved 12/18/2020 with conditions, including WPO approval for all phases of development proposed with SDP202000066. 9) Approved ISP combines areas approved for development under WPO201800044 (ABC phase 2; prior: 10 lots /criteria IIB), and AT0201800084 (phases 1, 3, 4, 5), a criteria IIC grandfathered design. AT0201800084 and now WPO202000058 route storm runoff to Fifth Street Place (wet pond). For the moment, mass grade SWM is not presented. Albemarle requests WPO201800044 Amendment 1 Application at earliest convenience, so that all phases of ABC (1,2,3,4,5) shown on SDP202000066 and with FSP have corresponding /approved SWM and ESC elements. (Rev. 2) Addressed; WPO2018-00044 Amendment #1 is under review. Ref. email sent 3/16/21. 10) Provide design /calculations to accompany SWM design for ABC Phase 2 (Apts. west of Old Lynchburg Road). (Rev. 1) Persists. Applicant: `Noted, this will take place in the future if/when that site is developed.' Asfollow- up: Please see clarification, above. FSP and WPO may not approve clearing forest to create a cleared site with higher runoff without SWM design that meets state SWM requirements, whether Criteria IIC (grandfathered), or IIB. Note: WPO201800044 includes SWM sufficient to meet SWM requirements for 10 SF homes, yet comment response indicates developer instead intends to clear without immediate plans to develop ABC Phase 2, but without SWM to address increased runoff once site transitions from forest to cleared condition. Clearing forest increases runoff. (Rev. 2) Addressed. Ref. sheet C10, WPO2018-00044 Amendment #1. s Ref. ABC Topographic pond drainage map, p. 7, 12/23/20 calculation packet. Review comments C1 1. Revise plan (sub -)title to incl. reference to WPO2020-00058. (Rev. 1) Addressed. Engineering Review Comments Page 5 of 8 2. Include Note to reference WPO2018-00044 for ABC, Phase 2, if this WPO plan is intended to support SDP202000066 approval. ABC Phase 2 must be shown on an approved WPO plan that matches mix of development shown with ABC Phase 2 (SDP2020-00066). For the moment, ABC Phase 2 is not shown with this WPO, and approved SWM for a 10-lot single family subdivision is obsolete, inconsistent with ABC Phase 2 apartment layout. Please consider prior -approved SWM facilities (biofilter, forest -open space easement) or BMP design sufficient to meet 9VAC25-870-65 /-66 for proposed apartment layout, Phase 2. Note: Part IIB criteria apply to areas that do not route to the Fifth Street Place SWM pond. (Rev. 1) Partially addressed. As -follow-up: Please see discussion above, and email sent 2/26/2021 5:24 PM. (Rev. 2) Addressed. As ollow-: SDP202000066 cannot show ABC Phase 2 Apartment layout. 3. Please include title sheet note reference to SDP2020-00066, Albemarle Business Campus Initial Site Plan. (Rev. 1) Addressed. 4. Revise WPO consistent with Engineering review comments for SDP2020-00066 dated 12/3/20. (Rev. 1) Addressed, 5. Source of boundary and topography: provide topographic data obtained within the last 12 months, or, at a minimum, verify that topography depicted on WPO plan is accurate (visually verified within last 12 months). (Rev. 1) Addressed. 6. Floodzone Note: Please revise date from February 4, 2005 to May 16, 2016, consistent with ordinance (text at) 18-30.3.2. (Rev. 1) Addressed, 7. Revise WPO Plan, as needed, to reflect phased construction. SDP2020-00066 proposes phased construction (Phases 1-5). Phase 2 requires SWM and ESC measures not included with WPO2020-00058. (Rev. 1) Partially addressed. As follow-up: Revised plan now includes mass -grade ESC measures for ABC, Phase 2, but as discussed 26-Feb, please transfer ESC measures for Phase 2 to WPO201800044 Amendment 1 Application, and provide SWM plan /calculations required for ABC, Phase 2 with Amendment Application. Also, item 9., below. (Rev. 2) Addressed, WPO2018-00044 Amendment #1 under review. Ref email sent 3/16/21. VRRM.xls included with WPO2018-00044 Amendment, sheet C10. 8. C3: Add phase lines that clearly delineate phased construction; items 2. 7., above. (Rev. 1) Addressed, 9. C5: ABC Grading plan (C5) only shows eastern portion of ABC depicted in the initial site plan (SDP2020- 00066, C0; this area is bounded by Region 10 (TMP 76-46F) to the N, Sterling University Place to the E (TMP 76-54A1), Fifth Street to the S, and Old Lynchburg Road to the W. The western portion of ABC shown on the initial site plan is not covered by this WPO plan. While Engineering can consider a WPO plan for a portion of the initial site plan, final site plan and even conditional ISP approval for all phases of Albemarle Business Campus require approved WPOs (SWM/ESC) for both eastern and western portions of the development. See C4, SDP2020-00066. (Rev. 1) Withdrawn. As follow-up: Please see discussion, above, email sent 2/26/2021 5:24 PM, and submit WPO201800044 Amendment 1 Application at earliest convenience. (Rev. 2) Addressed; WPO2018-00044 Amendment #1 under review. Email sent 3/16/21. C7 10. For sections of pipe or inlets in fill sections, request note on profile requiring adequate compaction beneath pipes /inlet/s, to limit risk of deflection, settling, or deformation. For example: (Rev. 1) Addressed. a. Between C4C5; B2 B3B3; B3 B4B4; and B3, 133A b. Beneath Str. B3. 11. Include label at Str. C2 for Y2" steel plate in floor of MH structure. (Rev. 1) Addressed. Applicant: `Structure C2 revised to avoid the requirement for steel plate at invert.' 12. Include label for safety slab for ME ht. >12-ft. (Str. A5, B3, B4, C2, CSA, CSB, for example). (Rev. 1) Addressed. Applicant: `Safety slab specified where needed. Some structures revised to avoid need for slabs.' 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 will be approved once comments sent as email 3/16/2021 11:18 AM are addressed. 1. C9: Include VDOT SL-1 detail (safety slab). (Rev. 1) Addressed. C12 2. Label basin floor (L x W). (Rev. 1) Addressed. Engineering Review Comments Page 6 of 8 3. Label basin riprap (L x W x D). (Rev. 1) Addressed. 4. Revise sediment basin contours to tie to existing contours. SB outfall pipe (proposed) grading ties to existing contours, but not the basin, itself. (Rev. 1) Addressed, 5. Provide grading and downslope ESC measures for staging area, if area is to be graded for trailer, material storage, equipment, etc. (Rev. 1) Addressed, 6. Show depression designed to capture /detain vehicle wash waters at PCE. (Rev. 1) Addressed. 7. Revise sequence to discuss 47.00' and 17.63' Ex. 36" culvert demolition. (Rev. 1) Addressed. 8. Label structures B2, B3, B4. (Rev. 1) Addressed. 9. Without proposed grade, it is unclear how runoff reaching Ex. 36" culvert INV IN=412.74' will convey off -site after sections of 36" culvert are removed, given —16' fill at proposed structure B3. Please clarify design via additional notes, labels, sequence narrative, proposed grade, and/or linework. (Rev. 1) Addressed. 'T [ Image removed with Rev. 1 comments.] 10. Show revised grading above new pipe installed between remaining sections of ex. culvert, near Fifth Street. (Rev. 1) Addressed. 11. Contours near riprap and drainage pipe labels appear to indicate an (existing, relic) on -site SWM facility. Provide note/s for this facility. If an active SWM facility that captures or detains runoff from Rt. 780, then consider effect of removal with ABC development. Ensure any runoff (from Rt. 780, for example) treated by existing on -site even poorly -maintained SWM facilities is treated to an equivalent degree in the ABC post -developed condition (will be, for phases 1, 3, 4, 5, since routed to pond), that performance effects of existing (even poorly -maintained) SWM facilities are reflected in pre- /post -development calculations for all portions of ABC development. Since areas routing to possible relic (apparent existing) SWM facilities eventually route to Fifth Street Place SWM pond, a simple label with leader line reference to 12/23/2020 calc. packet ABC topographic pond drainage map is su rcient response to comment, apart from need to provide SWM for ABC, Phase 2. (Rev. 1) Addressed. Applicant: `Note added to retain this relic facility. The facility does drain into proposed SWM system, but this does not alter the destination, treatment, or flow characteristics of the pond.' 12. Provide additional detail for proposed SB outfall pipe connection with existing 36" RCP. Please consider: (Rev. 1) Addressed. a. 25-yr (routed) water surface elevation at point of connection with ex. 36" RCP, and whether depression is adequate to contain Q25 release from SB, without flooding. Provide calculations. Applicant: `The VDOT inlet headwater nomograph is added to the SWM packet to show this. No flooding above downstream ridge of basin embankment occurs from the inlet control conditions from the 36" pipe. (Nomograph included in this submittal as a single loose-leaf sheet).' b. Means of protecting all existing on -site or offsite downstream storm drain pipes between ABC development and Fifth Street Place SWM pond from sedimentation, once existing pipe network is connected with proposed sediment basin that will be receiving construction -phase, sediment -laden runoff from a considerable area, once cleared of existing woods (8.20 Ac. DA). This 8.20 Ac. DA with significant vertical fall, west to east, will transition from best (forest) to worst (cleared /unvegetated, un-stabilized) land cover type during construction, until stabilized with temporary or permanent vegetation, or impervious paved surface leading to SWM conveyance. 13. Revise ESC phase 1 to control runoff during initial grading of existing contours until such time as mass grading allows runoff from the 8.20 Ac. DA to reach the proposed (ESC phase 1) basin. n belew cannot drain to basin in ESC phase 1, as depicted. Provide adequate interim stage ESC detail /measures. (Rev. 1) Addressed. [ Image removed with Rev. 1 comments.] C13 14. Resolve hotel /hotel parking vs. sediment basin conflict. Improvements not in conflict with sediment basin may be shown. Or, via notes, narrative, additional phased ESC (smaller multiple traps, or revised smaller basin), resolve any conflict between proposed ESC measures, and improvements. (Rev. 1) Addressed. 15. Resolve CWD — retaining wall conflict, where CWD is shown crossing the retaining wall. (Rev. 1) Addressed, 16. Label Main Street. (Rev. 1) Addressed. Engineering Review Comments Page 7 of 8 17. Phase 2 includes text reference to mass grading. Show proposed mass grading. Site falls —38' (vertical interval) west to east, yet no grading is shown to transition from existing condition to (phase 2 ESC) condition depicted on C 13. (Rev. 1) Addressed. 18. Additional comments possible, given 38' vertical interval effect on SB grading, once mass grading is shown. A single SB to control runoff from 8.20 Ac. mass -graded site may be unworkable. (Rev. 1) Addressed. Applicant: `Noted, basin should be sufficient to construct all but Building Phase 5 (the hotel), during which point dewatering techniques will be used to control sediment.' 19. Provide existing contour labels along RWD between Wahoo Way and SB, to aid review of diversion dike. (Rev. 1) Addressed. C12, C13 20. Provide phased ESC measures to correspond with improvements spaced (phased) over time. WPO plan should allow construction of SDP phases 1, 2, 3, 4, 5, independent of one another, if site plan presents phases independent of one another. (Rev. 1) Addressed. 21. Label diversions in N comer of site either CWD or DD, since effect on runoff is somewhat ambiguous. (Rev. 1) Addressed. 22. Show /label existing asphalt path parallel with Fifth Street. (Rev. 1) Addressed. 23. SF along or adjacent to Fifth Street appears unnecessary, given that contours appear to fall into the site. Safety fence (SAF), however, is required (and is shown) between Fifth Street and ABC development. (Rev. 1) Addressed, 24. Ensure SAF is positioned between asphalt path and land disturbance (also, Cam. (Rev. 1) Addressed. C14 25. Review phase 2 ESC measures that carryover to phase 3 that may conflict with paved path or paved site construction entrance on Old Lynchburg Road, Phase 3 ESC measures should not be shown installed in paved surfaces. (Rev. 1) Addressed. 26. Relocate phase 3 ESC perimeter measures, if, or as needed. (Rev. 1) Addressed, C16 27. Sediment basin (design table): a. Include DA (8.20 Ac.) treated. (Rev. 1) Addressed. b. Label basin side slopes (3: 1, for example). (Rev. 1) Partially addressed. As follow up: Please see New review item 30.1 below. (Rev. 2) Withdrawn, plan view indicates basin side slopes meet VESCH std. c. Recommend linework clarify baffles are not a single row of plywood, since several rows of plywood are required to construct 10' tall baffles. (Rev. 1) Addressed. d. Recommend min, baffle post size of 6" square given 10' height /weight these posts must support. (Rev. 1) Addressed. e. Provide riser anti -flotation calculations for 18" x60" x 60" concrete base, relative to basin bottom elev. (410') and riser crest elev. (420'). (Rev. 1) Addressed. Applicant: `Anti -flotation calcs included with this submittal as loose-leaf sheet, will be included with the basin calcs in final SWM packet.' f. Include /show anti -seep collar calculations, dimensions, number, and placement, if required. (Rev. 1) Withdrawn. Applicant: `With the use of corrugated pipes, anti -seep collars are not required as the exterior corrugation serves the same purpose as the collars.' New Comments below addressed with Rev. 2 28. C 17: Transfer to WPO201800044 -Amendment 1 Application, also, see email sent 2/26/2021 5:24 PM. 29. C18: Wet /dry volume provided are <volume required, for both traps, wet and dry volume. Please revise. 30. C13, C19: Please ref. VESCH, 1992, Std & Spec 3.14, p. I1I-80, Embankment cross-section, and revise embankment side -slopes to 2%,:1, or flatter, for embankment 10-14-ft. in ht., ensure min. top width>8-ft. From Sterling University Housing SWMPart 2, p. 1, e-attachment, K. Rucker, SE, to J. Anderson, 2/27/2019 5:07 PM [Image removed with Rev. 2 comments.] Engineering Review Comments Page 8 of 8 SDP2020-00066: east /west portions [ county GIS ] [ Image removed with Rev. 2 comments.] C4 [ Image removed with Rev. 2 comments.] SDP202000066, C7 C8C8 (phase 2, Apartment layout) [ Image removed with Rev. 2 comments.] WP02018000441 C3, Approved 12/13/18 Corresponds with ABC Phase 2 (Apartments): includes Level 1 biofilter and several forest /open space easement areas. [Images removed with Rev. 2 comments.] E. Mitigation Plan a. NA, no impact to stream buffers. The VSMP permit application, plans [calc. packet approved] and SWPPP may be resubmitted for approval when 3/16/21 email review comments have been satisfactorily addressed. Please submit items digitally with a completed application form. Process After approval, plans will need to be bonded, bonds are in process and are being coordinated with the county. After bonding is 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 (two applications, in this instance), they will issue permit coverage letters (two letters, in this instance). These should be copied to the county. After DEQ coverage is issued, via the coverage letters, 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, httos: //www.albemarle. orgIgovemment/community-develoi)mentlaooly-for/engineering-anal ications "'P0202000058 ABC 031621 rev2