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HomeMy WebLinkAboutWPO201600074 Review Comments WPO VSMP 2017-03-24COUNTY 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: Woodbrook Elementary School Addition Project file number: WP0201600074 Plan preparer: Timmons Group, Craig Kotarski. [craig.kotarski@timmons.com] Owner or rep.: Albemarle County School Board, Uletteri@kl2albemarle.org] Plan received date: Rev 1 — 30 Nov 2016 Rev 2 — 22 Feb 2017 Date of comments: Rev 1 — 5 Jan 2017 Rev 2 — 23" Mar 2017 Reviewers: Rev 1 — Bobby Jocz - VSMP Geoff Elsie VESCP Rev 2 — Bobby Jocz — VSMP/VESCP 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. The rationale is given in the comments below. The application may be resubmitted for approval if all of the items below are satisfactorily addressed. 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. 1. Provide signatures for the registration statement. Rev 2 — Addressed 2. Provide signatures for the Certification Statement (section 9). Rev 2 — Acknowledged 3. Complete/sign the Delegation of Authority (section 10). Rev 2 — Acknowledged 4. Provide a copy of DEQ coverage letter when obtained. Rev 2 — Acknowledged B. Pollution Prevention Plan (PPP) The PPP content requirements can be found in County Code section 17-404. Provide proposed locations for concrete washout, material delivery and storage, and portable ies as noted in PPP on the plans. Rev 2 — Addressed Engineering Review Comments Page 2 of 5 2. Revise plans for diverting wash waters to sediment basin. No diversion dike is shown adjacent to the construction entrance as stated. Rev 2 - Addressed 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. Remove Sheets C1.1, C1.2, LLO, L2.0. L3.0, U.1, L3.2, C4.0. Not needed for Erosion and Sediment Control or Stormwater Management review or installation. Rev 2 - Partially addressed, Remove sheet C7.0 and correct mislabeling of sheet C8.1. It is currently labeled as "Stormsewer Drainage Areas". Sheet 8.1 as labeled is missing, including the profiles for drainage structures SWM B - 204, 200 - 204, SWM B - 213, and 211- 204. Please correct 2. Re -name cover sheet to identify the submission as a VSMP plan, make sure to include the WPO submission number (WPO201600074). Rev 2 - Addressed 3. Original Signature of professional engineer will be needed for final submittal on both the plan sheets and supporting design calculations. Rev 2 - Acknowledged 4. Remove section of demolished pipe shown extending from SWM facility A to the roadway from the Auxiliary Site Improvements sheet [C6.0]. Verify all sheets are expressing intended information. Rev 2 - Addressed 5. As stated in site plan comments, provide details for proposed storm sewer structures (i.e. Doghouse MH, surface drains, DI-1, DI-3C, MH-I, etc). All structures must meet VDOT standards. Provide details for SWM facilities including, inspection and maintenance access/schedules/procedures, pipe inverts, profile views, cross sections, backfill materials and any other details necessary to properly identify and evaluate SWM facility designs. Rev 2 - Not addressed, SWM facility details and long term maintenance details must be provided as stated above. Details still not provided for Doghouse MH, and DI-1 structures. 6. Provide manufacturer specifications proving pollutant removal efficiencies specified in VRRM spreadsheet. Rev 2 - Addressed 7. Revise storm sewer profile labels to match the structures being represented in the profile. For instance, the profile showing STR 138-SWM A is labeled as STR 100-106, which is not what is represented in the profile. Please correct. Rev 2 - Addressed, however some profiles are missing, including the profiles for drainage structures SWM B - 204, 200 - 204, SWM B - 213, and 211 - 204. Provide all existing and proposed stormsewer in profiles. This includes Ex 16 -148. Please correct. -r-iding on profile for SWM A - STR 100 [sheet C8.0] or indicate no change. Rev 2 - Addressed 9. Yiumu scam uucs not match vertical scale presented in profiles [Sheet C8.0, C8.1]. Please correct. Rev 2 - Addressed 10. The labeling of proposed drainage areas (A and B) in Runoff Reduction Spreadsheet, design calculations, and drainage area maps is inconsistent and needs to be corrected. The labels appear to bP Q-7-n-1 in flip Runoff Reduction Calculations. Rev 2 - Addressed 11. In one vv aver VuaiiLy Analysis section on sheet C10.0, the value provided for Q(10) Pre -developed Engineering Review Comments Page 3 of 5 differs from the one shown calculated for the 10 year pre developed condition in the model. In addition, the elements labeled in RV (1 Year Post) under "Drainage Area A" are mislabeled as Post Developed B detained and Post Developed B Un-detained. Please verify and correct this. Rev 2 — Partially Addressed. The water quantity section corrected; however, Water quality analysis figures on sheet C10.0 now do not match those represented in the VRRM spreadsheet for; disturbed acreage, pre/post-developed conditions, and total load reduction. Please Correct. 12. Verify throat lengths for inlets are correctly identified and modeled on the LD204 form. Structures are shown to have throat lengths of 2' which contradicts throat lengths identified for those same structures elsewhere in the plans. Rev 2 - Addressed 13. Verify calculations for STR 122 and STR 106 are correct. Carryover is shown through STR 122, but is not modeled entering STR 106. Rev 2 - Addressed Additional Review 2 Comments: 14. Inlet 122, as referenced in the LD204 spreadsheet and storm drainage area map, does not exist as an inlet identified on stormsewer system in plan views or drainage profiles. Please correct or clarify. 15. Some of the drainage areas in sheet C8.1indicate drainage to inlets that do not exist as part of identified stormsewer system in plan views or drainage profiles. For example, the roof of the gym and stage/dining areas are indicated to be draining to structures 123 and 121 respectively on sheet C8.1, but those structures are not identified anywhere else in plans or calculations. Please correct or clarify. 16. Water quality analysis figures on sheet C10.0 do not match those represented in the VRRM spreadsheet for; disturbed acreage, pre/post-developed conditions, and total load reduction required. Please correct. 17. Structure 108 exceeds maximum spread conditions. Inlets in sump conditions must maintains spreads less than 10'. 18. Structure Ex. 12 is modeled to not intercept any flow, as a result a large amount of carryover is shown leading to concerns about flooding. Please correct or clarify. D. Erosion and Sediment Control Plan (ESOP) Virginia Code §62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESCP. This plan is disapproved, and the reasons are provided in the comments below. The erosion control plan content requirements can be found in County Code section 17-402. Remove Sheets C1.1, C1.2, L1.0, L2.0. L3.0, U.1, L3.2, C4.0. Not needed for Erosion and Sediment Control or Stormwater Management review or installation. Rev 2 — Partially addressed, Remove sheet C7.0 and correct mislabeling of sheet C8.1. It is currently labeled as "Stormsewer Drainage Areas". Sheet 8.1 as labeled is missing, including the profiles for drainage structures SWM B — 204, 200 — 204, SWM B — 213, and 211— 204. Please correct 2. Correct title block for Sediment Basin Design, Sheet C3.0, currently refers to Permanent Seeding for the Piedmont. 3. Rev 2 — Addressed 4. Sediment Basin detail elevations do not match those provided on plan sheet C3.1 and C3.2 (for: top of dam elevation, barrel out invert, bottom of basin, principle spillway crest, etc.). In addition, basin volumes provided in the detail do not match those provided in the component breakdown Engineering Review Comments Page 4 of 5 spreadsheet. Please correct and provide updated calculations if necessary. Ensure basin design is compliant with VESCP standards. Also note: Baffles required if L/We is < 2, not greater than 2 as stated in detail spreadsheet. Rev 2 — Addressed, replaced basin with sediment trap 5. Shnxx, ctn, as an Rev 2 — Addressed 6. 'v erny iocaLion of Construction Entrance. It should be located at the entrance to the construction site with wash facility or barricade. Current location appears to be too far inside site. Rev 2 — Addressed, second CE added 7. Add Safety Fence with signage that reads Danger Quicksand around Sediment Basin. Rev 2 — Addressed, basin replaced with trap 8. Show detail for tree protection, temporary slope drain, and culvert inlet protection as specified to be installed in the structural practices and sequence of installation notes presented on sheet C3.0. Also specify where these practices will take place on site. If these practices are not to be used, remove them from the narrative. Rev 2 — Addressed 9. Show Permanent Seeding and Mulching at the CMP pipe from the Basin to the doghouse. Sheets C3.1 and Sheet C3.2 insert. Rev 2 — Addressed 10. E&S measures and limits of clearing and grading must extend to the portion of stormsewer installed from the north portion of the site to Brookemere Drive for Phase II E&S (Sheet C3.4). Rev 2 — Addressed 11. Extend silt fencing across the southern portion of the site along Idlewood Drive. Rev 2 — Addressed Additional Review 2 Comments: 12. Correct deficiencies in E&S narrative: a. Incorrect project area identified in description. b. Stormwater runoff considerations state that nutrient credits will be purchased, however quality will be treated using Bayfilters according to SWM plan. c. Structural practices still include sediment basin description and maintenance practices. Please correct to sediment trap as specified. d. Phase II sequence of construction still includes the conversion of sediment basin to underground facility. Please update to reference current E&S plan measures. 13. Provide detail for paved construction entrance per County Design and Standards Manual Ch. 3. 14. Please confirm drainage area to sediment trap. GIS appears to show the provided trap's drainage area to be larger than 3 ac. Sediment traps are not to be used for drainage areas larger then 3ac. 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. Engineering Review Comments Page 5 of 5 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; httD://www.albemarle.oriz/deDtforms.asD?deDartment--cden2wr)o Bobby Jocz, EIT Civil Engineer 1 (434) 296-5832 ext: 3283 County of Albemarle Department of Community Development 401 McIntire Rd. Charlottesville, VA 22902