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HomeMy WebLinkAboutWPO202000037 Action Letter 2020-10-07� AI �h �lRGIN�P COUNTY 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: Galaxie Farm VSMP Project file number: WPO202000037 Plan preparer: Keane Rucker, Shimp Engineering [ keane a shimp-en ing eering.com ] Owner or rep.: David S. or Anna Marie Witmer, 444 Rookwood Dr, Charlottesville, VA 22903 NSCROAGALLIFREYENTERPRISES. COM Plan received date: 2 Jul 2020 (Rev. 1) 22 Sep 2020 Date of comments: 17 Aug 2020 (email, August 17, 2020 4:42 PM) 18 Aug 2020 (rev. /edited; this Memo) (Rev. 1) 7 Oct 2020 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 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 ESCP, (3) a SWMP, and (4) any TMDL measures necessary. SWPPP: Provide. Please use SWPPP template, link: httys://www.albemarle.org/home/showdocument?id=166 (Rev.1) Partially addressed. As ollow-up: 1. Sec. 1. Registration Statement: a. Cover: i. Parcels under development appear to be 9, 15, please check /revise as needed. ii. Please include reference to WP0202000037 in SWPPP title. iii. Revise SWPPP title project name to match WPO Plan title. b. Sec. IV.E: List Albemarle County since parcels under development are within Albemarle County MS4. C. Sec. IV.F: Check `yes' since Galaxie Farm is (itself) a common plan of development (vs. single parcel without subdivision). 2. Sec. 4, ESC Plan: Include plan sheets, once review comments addressed. 3. Sec. 5, SWM Plan: Include plan sheets, once review comments addressed. 4. Sec. 6.A., PPP Exhibit — include in I I" x 17" Exhibit in SWPPP. 5. Sec. 6.E., Person: Name individual responsible for PPP prior to permit registration with DEQ. B. Pollution Prevention Plan (PPP) 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) Not addressed. Applicant response (9/21/20 letter): `These items are included in the PPP.' As follow-up: A graphic plan /Exhibit was not included. Please provide an I I" x 17" exhibit at Sec. 6.A. of SWPPP to include: a. Rain gauge b. Portable sanitary facilities c. Covered non -hazardous solid waste dumpster d. Concrete wash -out draining to trapping device Engineering Review Comments Page 2 of 9 e. Paved construction entrance w/ spray wash f. Paint /Stucco /Solvent storage g. Lined (10ml) on -site fuel storage containment sized for fuel volume + 10-yr storm event x 1.1 [ Image immediately below is from county template at: hfti)s://www.albemarle.org/home/showdocument?id=166 Section 6. Pollution Prevention Plan. (reference County Code 17404 and State Regulation 9VAC25-880-70 part 11 section A.4) A. Plan showing pollution activities and prevention practices (Provide a reduced Itall of the following activity locations are clearly marked. Keep this plan up-to-date with ongo' g site changes and inspections.) C. Stormwater Management Plan (SWMP) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is disapproved for relatively few reasons listed, below. The stormwater management plan content requirements can be found in County Code section 17-403. [ Note: Two item # is are an error, but both items are addressed or NA. ] 1. Any Forest and Open Space used in the VRRM worksheet as a Post -Development land cover will need to be shown on the plans and labelled as'SWM Forest and Open Space'. The following note will need to be placed on the plan: "The SWM Forest and Open Space Easement is subject to the guidance set forth by DEQ in the Virginia Stormwater Management Program. The areas will remain undisturbed in a natural, vegetated state, except for activities as approved by the local program authority, such as forest management, control of invasive species, replanting and revegetating, passive recreation (e.g., trails), and limited bush hogging to maintain desired vegetative community (but no more than four times a year)." (Rev. 1) Addressed. 1. Pg. 1 and 2 of SWM calculation packet reference design intent to restore degraded sections of Cow Branch to comply with 9VAC25-870-66(B) without submitting design for stream restoration. Plan appears to lack any referential design data for riffle /run sections, sinuosity, stream bed, analysis of existing stream data, or plan /profile information for proposed revised stream centerline or any in -stream structures required to effect natural stream restoration. Albemarle has direct experience contracting with design and construction firms to restore degraded streams, and anticipates revised SWM plan that furnishes requisite natural stream design methodologies. Note: stream bank plantings alone are not natural stream restoration. FES /Water Resources will be invited to review and comment on natural stream restoration elements of design. Note on sheet C5: `Restore channel between culverts B and G per natural design standards in accordance with 9VAC25-870-66-B(2)' is a statement that references, requires and depends on design. (Rev. 1) NA Applicant: `The storm system outfall location has been changed. This is due to several reasons, primarily being that a revised routing which changes the location of POA 1 to be at the current point where local runoff hits Cow Branch is easily achievable without having to perform channel restoration and without major revision to the subdivision design. So for the current design, no restoration is proposed, and all references to this have been removed from the plans.' 2. Additional comments possible, relative to item L, above. (Rev. 1) Acknowledged. 3. Revise per (related) preliminary plat or road plan review comments. (Rev. 1) Addressed. Applicant: `All changes related to Road Plan & Prelim. Plat review comments are included in this submittal.' 4. Remove all portions of Lots 57, 58, 59 from 100' stream buffer (Also: Engineering preliminary plat and road plan review comments). (Rev. 1) Addressed. 5. CS CT Show all portions of property. SSW comer of development does not appear to be visible on these, and perhaps other sheets. A match -line inset of developed areas not yet shown is an acceptable approach. (Rev. 1) Addressed. 6. C19 Engineering Review Comments Page 3 of 9 a. Show multiple inlets to single structure, graphically, for example (Rev. 1) Addressed. i. Str. E6 ii. Str. E7 b. Label MHs with 4' vertical interval between INV IN and MH floor to receive Y2" steel slab. (Rev. 1) Addressed. c. Label Str. requiring VDOT SL-1 (safety slab, In. >12'). (Rev. 1) Addressed. 7. Revise Runoff Quality Narrative (p. 2 calc. packet) to reflect post -developed 2.80 Ac. Forest /Open space land cover condition (p. 84). Also: a. Final plat must include metes and bounds that establish 2.80 Ac. forest /open space easement (Rev. 1) Persists. Applicant: `Noted. We have already hired Roger W. Ray & Associates to complete the final subdivision plat, they will prepare this using our AutoCAD linework as well as Road & VSMP plans.' b. Revise 0.58 Ac. SWM Forest /open space easement to exclude a portion proposed FOS easement immediately east of sidewalk, and Lot 65. Galaxie Farm FICA, owner of Lot 65, and maintenance crews cannot be expected to understand, appreciate or abide limits on maintenance of FOS area proposed to approach within 1' of sidewalk. Engineering cannot approve west boundary of 0.58 Ac. FOS area, until revised to allow reasonable buffer for normal subdivision maintenance of open space. In other words, HOA will bush hog areas adjacent to sidewalk more than 4 times per year; and will likely maintain areas within 25' of sidewalk in lawn or turf condition. Revise, and adjust VRRM and on -site SWM design and nutrient credit purchase proposals, as needed. (Rev. 1) Addressed. Applicant: `Noted. Easement shifted 5' away from both ROW adjacent to sidewalk and from Lot 65. 5' gap between these areas will provide an adequate buffer for regular lawn maintenance —this is plenty of width for an industrial riding lawnmower to pass in a stripe alongside this area. ... A 25' wide buffer area is not necessary ... This revision has reduced the FOS easement by 0.02 acres —this has been updated in the VRRM spreadsheet and throughout the VSMP plans.' 8. VSMP Plan SWM Calculation Packet a. Pg. 1 —Revise ref, to PGA A to POA 1, consistent with terminology elsewhere in packet. (Rev. 1) Addressed. b. Pg. 4 — 8 appear to be section dividers. Please align dividers with corresponding packet contents. Relocate divider pages to sections of the calculation packet that follow /present listed information. Otherwise, packet sections are indistinguishable with data difficult to locate, trace, or review. (Rev. 1) Addressed. c. Pg. 12 —Revise POA 2 label text color to black /similar, so readable. (Rev. 1) Addressed. d. Pg. 13 v. Pg. 85: It is difficult to reconcile table values (p. 13) listing on- /offsite turf /impervious areas that rout to BMP 1 (via Str. 172) with VRMM.xIs 4.60 Ac. /1.60 Ac. turf /impervious area values (pg. 85, DA A) that route to Mfr. Treatment. Please clarify. Video -call may be helpful. (Rev. 1) Partially addressed. Applicant: `Noted, this ... has been revisited and clarified. One note —after additional review of upstream areas —we found that the Albemarle Health & Rehabilitation Center (noted in the packet as MFA @Mill Creek) drains into a biofilter, which drains into the Galaxie Stormtech BMP. In —2015, Shimp Engineering had completed the site plan and as-builts for the MFA @Mill Creek design. Thus, to most accurately account for that drainage area, we have imported the old HydroCAD design for MFA which includes this offsite biofilter into our Predev and Postdev SWM analysis. In reviewing this old design, we found that the WA biofilter provides a 65% nutrient removal. So to account for this treatment, we only accounted for the remaining untreated nutrient load in the VRRM spreadsheet. This was the difference in total area (100%-65%=35%): so the equivalent of 35% of the MFA site is untreated area which could be claimed as new treatable area in the VRRM spreadsheet. The physical design of the BMP still incorporates the full MFA site area (refer to HydroCAD modelling) —but we have now ensured this BMP does not "double -dip" nutrient removal. We also confirmed that there are no other upstream BMP's which drain into the Galaxie Stormtech BMP. Thus, the VRMM spreadsheet now accurately represents the treatment provided by the new BMP." Engineering Review Comments Page 4 of 9 As follow-up: From WPO201200087 (MFA @Mill Creek) Calculations /undated -untitled (CV), p. 1: O ACSA Bypass Fire�tion 0--0A Site Dominion Cram ` a Cale BioAlter v a �-o Frazier Galaxie Residue WPO201200087 Calculations (Shimp Engineering), 8/12/13, 64-pg. doc (CV p. 4: -- �• `\ Pre -Development Drainage Map �b Fire_! f trcn .. •• 138 495 SF 1................................................. �• \ J .\. •+•.....\............................. i � 1 i i t l I Fr fi r '• �To�a'c 2D-F ; �6u, 560 WPO201200087, Final Site Development Plan for Albemarle Health & Rehabilitation Center, 09, Landscape Plan (Shimp Engineering) references an existing SWM easement at deed bk.-pg. 4425- 165. Instrument at 4425-165 is power of attorney. This power of attorney references a plat dated August, 2013, revised October 9, 2013, but the plat is not attached, and if recorded, it is unclear where. As follow -up -up: i. Since an upstream/offsite BMP is relied upon in calculations for Galaxie Farm, provide accurate bk.-pg. reference to SWM easement for the biofilter at Albemarle Health & Rehabilitation Center. ii. Images above from MFA project require some clarification, for example: 1. There appear to be three paths for MFA downslope runoff, but this may be in the pre -developed and not post -developed condition. Engineering requests post - developed runoff drainage map downslope of MFA development. 2. HydroCAD schematic above shows Galaxie residue apparently not receiving MFA biofilter discharge; request clarification. iii. With WPO202000037, provide MFA post -developed turf and impervious area values that drain to the biofilter and then to Galaxie Farm so we may compare with VRRM.As for Engineering Review Comments Page 5 of 9 Galaxie Farm. It is unclear without post -developed drainage map for MFA and tabular (sf) data for turf /impervious areas that drain to the biofilter how to allocate additional treatment (phosphorus reduction) to already -treated runoff that reaches Galaxie Farm StormTech Mfr. system. Provide maps, tables, etc. that align with MFA post -developed conditions (p. 17, Cale. packet) for comparison between MFA post -developed condition, including WA BMP, and Galaxie Farm VRRM.xls. iv. Revise EBE (p. 68 /Cale. booklet) reference to pg. 31 to pg. 32 (RVP,e). e. Pg. 81: this table is difficult to evaluate, please: i. POA 3 (Entire site runoff) 10-year Q pre/post <10cfs, while POA 1 and POA 2 onsite runoff 10-year Q pre/post are orders of magnitude higher. Please clarify. (Rev. 1) Addressed. Applicant: `Clarified with narrative.' ii. For every Q 1-yr, 10-yr value in any table on pg.-8 1, please list corresponding HydroCAD letter descriptor and pg. 4. Additional comments possible, once correlation provided. Albemarle commends sophistication, elegance, detail, and accuracy of design, but cannot trace it with ease to the point we are able (yet) to confirm compliance with 9VAC25-870-66. (Rev. l) Addressed. Applicant: `Notation has been clarified.' iii. Section of Cow branch between POA 1 and POA 2 proposed to be restored assumes certain channel capacity /ability to absorb additional Q 1-year post -developed flow (12.00cfs). Provide natural method stream design for this section of Cow Branch that proves the point, computationally. (Rev. 1) Addressed. Applicant: `Design has been revised so that this is now not needed.' iv. Storm pipe capacity (LD-229): Ensure flow does not exceed storm pipe capacity. Also, please ref. Engineering preliminary plat and road plan review comments re. pipe capacity. (Rev. 1) Addressed. Applicant: `This has been accomplished with recent revisions.' 9. C5 includes label `slopes surveyed <25%'. Submit survey for Engineering review. (Rev. 1) Addressed. Applicant: `All Preserved Slopes disturbance removed.' 10. Revise grayscale text across all plan sheets to print black, rather than grayscale. It is difficult to review and recognize labels, notes, dimensions, etc. (Rev. 1) Addressed. 11. Revise C8 and C20 , and elsewhere as needed, StormTech stone invert elevations for consistency, for example, bottom of stone is given in labels, notes or table on these sheets as: 474.00, 474,75, 475.00, (Rev. 1) Addressed. 12. C20 a. Revise to resolve weir /stair 2 conflict. (Rev. 1) Addressed. b. Detail 3: show 6" solid PVC underdrain to Str. E6 in plan view (C7) and in pipe profile, C19. (Rev. 1) Addressed. Applicant: `Design revised to route 6" PVC into Str. E6Z after weir. 6" PVC shown in details and profiles. Main BMP outlet profile (E6-E6Z) copied onto C20 for ease of reference.' c. Supplement Stormtech BMP profile with SWM facility overall L x W dimensions in plan views (to aid review, construction inspection, As -built review, and bond estimate -reduction -release). (Rev. 1) Addressed. d. Weir E3 details: i. Label weir plate thickness. If weir plate is precast, indicate with label. (Rev. 1) Addressed. ii. Provide 18" x 30" trash rack detail. (Rev. 1) Withdrawn. Applicant: `Trash rack removed. Rationale: 1. A trash rack is unnecessary for an opening this large as debris large enough to obscure or clog this orifice is unlikely to float, and unlikely to enter the BMP anyway. 2. With the exception of large storms, most debris will be intentionally caught in the Isolator Row (that is its function). Regular debris is not anticipated around the weir/orifice. Engineering Review Comments Page 6 of 9 3. Even with debris, a trash rack would cause more of a maintenance burden, as it could hinder debris such as grass clippings, leaves, small branches from passing through this orifice, and trap it in the manhole whereas without a trash rack it could pass through. The above -mentioned debris would not prevent a downstream nuisance, as the larger downstream storm sewer has more cross - sectional area than the orifice. 4. Additional space for maintenance activity in the manhole will provide better benefit to the function of the BMP than a trash rack. Thus, these considerations dictate that trash rack be removed from this orifice.' iii. Resolve ladder /trash rack conflicts, if any. (Rev. 1) Addressed. Applicant: `Ladder/trash rack conflicts removed. See response to d. ii, above.' iv. Labels ref. E7Z and E7, which is confusing. Revise to reference single structure. (Rev. 1) Addressed. 13. This item does not request revision but notes that USGS StreamStats peak flow (a regression methodology) predicts significantly higher peak flow than the Southern Piedmont Rural Regression Equation methodology referenced in the calculation packet (Link: httl)s:Hstreamstats.usgs.gov/ss/ ) An online pipe capacity calculator appears to indicate dbl. line culverts A and B have capacity for peak flow predicted by USGS StreamStats. Were this not the case, review would request design revision. (Rev. 1) Withdrawn. Applicant: `Noted, the USGS StreamStats website is a useful resource, we appreciate you sharing it. Since Southern Piedmont Rural Regression Method is a standard accepted by VDOT for computing peak runoff, and since it produces similar computation results as the HydroCAD peak flow, (added to packet), we will not replace the contents of the packet, but appreciate the additional redundancy in calculation.' [series of StreamStats or submittal images removed with Rev. 1 comments ] a. Stream stats, Attached, Q25,1, Culvert A (DA, 0.23 Mi.2)=310cfs G_._....__ USGS with eale. felieFt, _ 93 Q25, Culvert A=202.5cfs b. Cale. report, culvert A, 133.2 Ac. ( P. ° C. On-line Manning pipe flow calculator: D=4', n=0.012, slope=0.0533, 0.95 capacity:!* * A single line pipe calc., but dbl. line is proposed —Also: exit _ corresponding with Y2 x Q2,, (or Yz x 57.2cfs) =� ( % of full depth =0.1905) Link: http://www.hawsedc.com/engcalcs/Manning-Pipe-Flow.p_hp d. Stream stats, Attached, Q25-Y,-, Culvert B (DA, 0.51 Mi.2)=512cfs Compare USGS with calc. report, p. 93, Q25, Culvert B=347.9cfs e. Cale. report, culvert B, 338.1 Ac. ( p. ° MOn-line Manning pipe flow calculator: D=5', n=0.012, slope=0.0344, 0.95 capacity: 562.3cfs* * A single line pipe calc., but dbl. line is proposed —Also: exit _ corresponding with Y2 x Q2-r, (or Yz x 83.1cfs) � ( % of full depth =0.1906) g. About Sqe Stat. 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 canbe approved once email with (and plan sent to) USACE are shared with Albemarle (items 8, 9, below). The erosion control plan content requirements can be found in County Code section 17-402. 1. CIO-C13 a. Revise LOD to show no disturbance within stream buffer, except minimal grading needed to construct stream crossings ( x 2) or to install drainage structures, or pipes. Disturbance within stream buffer is constrained by ordinance, and LOD shown appears to exceed minimal required disturbance within the stream buffer. (Rev. 1) Addressed. Applicant: `LOD slightly revised to be as small as possible within the stream buffer area. LOD may appear excessive on some sheets due to the disturbance required to remove the existing Galaxie Farm Lane pavement, as well as to allow enough room to install Cow Branch culverts and riprap. The best graphical description which dictates the LOD required is shown on C 10 — Phase 1B.' Engineering Review Comments Page 7 of 9 2. C5 or CT On either sheet, dimension riprap at all pipe outfalls (L x W x D). Labels are helpful, but additional detail is needed for review, bond estimate, construction inspection, etc. (Rev.1) Addressed. C7 C8C8 3. Provide additional proposed contour labels. (Rev. 1) Addressed. 4. Wherever proposed lot grading falls toward a street (Road Bl or D, for example) provide collection behind curbing (yard inlets, for example) to convey runoff into piped storm conveyance. As -built grading does not admit lot runoff to cross back of curb to gutter. Recall, for example, multiple low areas behind curb during recent bond inspection at Riverside Village. Design is theoretical, but for cross -lot runoff to actually reach in -street storm lines, provision must be made for runoff to cross beneath curb to reach the in -street system. Note: Pg. 13 of Cale. packet makes clear that offsite runoff (via multiple TOC pathways /Str. 172) reaches BMP 1. Design must ensure these runoff pathways exist (as designed) in the post -developed (As -built) condition. (Rev. 1) Withdrawn. Applicant: `We appreciate Engineering's concern for ensuring the goals of the plan translate to effectiveness in the field, however if poor grading or unfinished lot delivery causes issues that prevent runoff from following plan design, these items must be corrected in the field. If as -built inspections require regrading to achieve design objectives, then that must be accomplished.... Additional conveyance will not be provided behind curbs since this would be redundant infrastructure with undue cost burden for both initial construction and long-term maintenance. Also, the VDOT road calculations show that the existing road infrastructure can readily achieve the drainage objectives of this plan.' Engineering accepts and appreciates (these) well -reasoned points. 5. C9: Project Description Notes: a. Note 1: Owner /developer submits application for and obtains an approved plan, unless contractor is a licensed surveyor, or professional engineer. (Rev. 1) Addressed. b. Note 2: revise to read `Installation of temporary erosion and sediment...' (Rev. 1) Addressed. c. Ref comments for CIO — C 13, and revise C9 sequence notes, as needed. (Rev. 1) Addressed. C10 6. Label STI, ST2 weir outfall dimensions (L x L). (Rev. 1) Addressed. 7. Provide demolition Note/s, Phase IA. (Ex. building, Ex. drive: TBR) (Rev. 1) Addressed. Applicant: "`Demo" leader notes added.' 8. Coordinate with USACE for permit coverage (work in a live stream, cofferdam, structure installation, stream impact /loss of stream reach). Provide evidence of USACE NW permit issuance. (Rev. 1) May persist. Applicant: `Per attached email with Vinny Pero at USAGE, this project falls under nonreporting Nationwide Permit 18.' As ollow-up: Please send email with Vinny Pero to reviewer (was not attached). 9. Estimate /report live stream reach loss (LF). (Rev. 1) Partially addressed. Similar to item not attached, please send plans sent to Vinny Pero to reviewer. Anticipate loss of live stream reach: 1451f. [Applicant: `We have attached the plans that were sent to Vinny which calculates the loss and fill within the stream. Loss of live stream reach: 145sf.'] 10. Provide notes, details re. Ex. well abandonment. Provide copy of coordination with VDOT on topic of well abandonment within future VDOT ROW (Road A). (Rev. 1) Addressed. 11. Provide ESC Legend: Line -type symbols /meaning can be discerned, but legend is needed for clarity, for stream diversion, DD, RWD, SF, tree protection, etc. (Rev.1) Addressed. 12. Provide Note or revise Phase IA sequence to eliminate apparent STI — Ex. driveway conflict. (Rev. 1) Addressed. 13. Revise sequence Note 6 (phase 1B) to reference Road A, rather than Road I. (Rev. 1) Addressed. 14. Revise sequence Note 5 (phase IA) to reference culverts A and B. (Rev. 1) Addressed. 15. Revise sequence Note 6 (phase 1B) to reference culverts A and B. (Rev. 1) Addressed. 16. Remove storm line D from Phase IA AB unless installed with Phase 1. (Rev. 1) Addressed. 17. If storm line D is installed with Phase 1, show ST2 in storm line D profile. (Rev. 1) Addressed. C11 18. Label Rt. 20. (Rev. 1) Addressed. 19. Provide ESC legend. (Rev. 1) Addressed. Engineering Review Comments Page 8 of 9 20. Remove storm line D unless installed with Phase 2. (Rev. 1) Addressed. C12 21. Provide SF (DD, or similar) behind upslope curb to protect surface of roads A, B, C, D from silt /sediment deposition. (Rev. 1) Addressed. 22. PCE at Rt. 20 may be removed, once Road A is paved. (Rev. 1) Addressed. 23. Show relocated stone /paved construction entrances at points construction vehicles may leave paved development road surface and enter graded earth areas. (Rev. 1) Addressed. 24. Label SB riprap outfall dimensions in this, or other view (L x W). (Rev. 1) Addressed. 25. Provide temporary rock -lined SCC upslope of and parallel with FD that receives runoff from DD and DV shown along south edge of parcel, south of Road C. Momentum and volume of sediment -laden runoff exiting DV for FD will likely cause recurrent erosion issues unless rock -lined SCC conveys runoff to SB. (Rev. 1) Addressed. 26. If runoff from partially -stabilized graded slopes is meant to sheet across Road A to reach the SB, this cannot be approved. Once Road A curb and gutter is installed, sediment -laden runoff that reaches the base - asphalt surface of Road A will be confined by C&G. Revise ESC Phase 3 so runoff from all areas intended to be controlled by the sediment basin, reaches the SB. Ensure curb inlets, once constructed, are protected adequately during all phases of construction. (Rev. 1) Addressed. Applicant: `Runoff is not intended to flow across street, error in linework has been corrected.' C13 27. Revise proposed permanent DV along south edge of development to underground piped storm conveyance. Also, ref. Engineering review comments on road plan, and preliminary plat. (Rev. 1) Addressed. Applicant: `Noted, DV will be replaced with piped system during phase 4. Shown on C13.' 28. Provide sequence /narrative /symbols /linework for coffered work area required to construct Road F. (Rev. 1) NA. Applicant: `Since Road F was removed this is no longer required.' 29. Provide PCE at Int. Road F and Rt. 20, whether it is intended to be used or not. It will likely be used as a site entrance, despite design intent. Albemarle County inspector may, at his discretion, not require a paved construction entrance at this location, but Road F is to be paved, so a paved CE is appropriate. (Rev. 1) NA. Applicant: `Since Road F was removed this is no longer required. Ex. Avinity fire access road cannot be used for construction (since it is offsite property), so none will be provided for this either.' 30. Provide SF, diversion, etc. to protect surface of road E, once constructed, until upslope DA is stabilized. (Rev. 1) Addressed. Applicant: `Silt fence will be sufficient, and is now provided.' 31. Include narrative sequence (Note 9), symbols, measures that outline/describe stream channel restoration activities in adequate detail, and offer adequate stream protection during this phase of the project. (Rev. 1) Addressed. Applicant: `Stream channel restoration no longer proposed.' E. Mitigation Plan 32. C17, Mitigation Plan: a. Please provide source of Mitigation Option A (channel restoration) requirements. Although used in the past, Crozet Court subdivision, for example, reviewer needs to identify source of this option. (Rev. 1) Addressed. Applicant: `This came from an old Albemarle County E&S guidance document, however channel restoration is no longer proposed.' b. Math: Since only 1.32 Ac. of unforested buffer appears available for mitigation plantings, the proposed 1600 bare root seedlings at 1,210 stems /Ac. ( planted 6' x 6' OC) appears to represent a maximum, but (related to a., above) were this not the case, the 2:1 plantings : area of buffer impact ratio would apply to 1.26 Ac. area disturbed within stream buffer. Table narrative on C 17 credits 1 LF channel restoration as offset for 100sf disturbed buffer. Again, reviewer not familiar with source of channel restoration buffer impact offset credit. Also, please note that 1,210 seedlings option (Option C, Table B, DCR Riparian Buffers Guidance Manual, p. 95) requires applicant to enter into a 5-year maintenance and performance guarantee, which will also stipulate minimal Engineering Review Comments Page 9 of 9 survival required after two growing seasons of 600 plants per Ac. Provide 5-year maintenance and performance guarantee as condition of VSMP /WPO plan approval. (Rev. 1) Partially persists. Applicant: `Math updated to reflect strategy revision. DCR source listed. 5-yr maintenance and performance guarantee noted (guarantee documents will be handled by Nicole Scro). Additional notes added.' c. Provide planting pattern ( 6' OC). (Rev. 1) Addressed. d. Provide list /table of proposed mitigation plant species (type /count) from Albemarle County Approved planting list (to be evaluated by Water Resources staff). (Rev. 1) Addressed. e. Channel Restoration Instructions is inadequate. Also, see comments elsewhere. Natural stream restoration design is required for plan approval to support 9VAC25-870-66 compliance. (Rev. 1) NA. Applicant: `Stream channel restoration no longer proposed.' The VSMP permit application, plans, and calculation packet may be resubmitted for approval when all comments have been satisfactorily addressed. Please submit items digitally with a completed application form. 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 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; hops: //www.albemarle. org[govemment/community-development/aoly-for/engineering—applications WP0202000037 Galasie Farm subdiv 100720rev1