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HomeMy WebLinkAboutWPO202000042 Approval - County 2020-11-17Phone (4341296-5832 Project: Project file#: Plan preparer: Owner or rep.: Plan received date: (Rev. 1) (Rev. la.) Date of comments: (Rev. 1) (Rev. la) Reviewer: Cif 1T COUNTY OF ALBEMARLE Department of Community Development 401 McIntire Road, Room 227 Charlottesville, Virginia 22902-4596 Fax(4341972-4126 VSMP Permit Plan Review 2435 Gobblers Ridge Pond "PSGI2 VSMP WPO202000042 Jim Taggart, PE, Roudabush, Gale & Associates, Inc. Physical: 999 Second St. SE, Charlottesville, VA 22902 Mailing: 435 Merchant Square, Suite 300-159, Charlottesville, VA 22902 JTagggq@roudabush.com loday@roudabush.com Calvin W. Dabney / Sandra D. Dabney 2435 Gobblers Ridge, Charlottesville, VA 22902 [ dabnevcw(a),,aol.com ] 9 Sep 2020 26 Oct 2020 16 Nov 2020 30 Sep 2020 16 Nov 2020 17 Nov 2020 —Approved 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 approved. A. Stormwater Pollution Prevention Plan (SWPPP) (Rev. 1) Addressed. 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. Submit 2019 VPDES Permit Registration, Sec. 1, SWPPP. Link below. 2. Revise SWPPP (12-section county template). Note: LOD =1.43 Ac. Link, below. a. Revise SWPPP title pg: Identify project, preparer, date, include ref, to plan title (2435 Gobblers Ridge Pond), and WP0202000042. b. Revise SWPPP Sec. 1, 2, 3 of SWPPP. Project is not exempt. Please call if any questions. c. Provide update to Sec. 4 of SWPPP, once all ESC Plan comments addressed. d. Provide Sec. 5, SWM Plan. e. Sec. 6.A.: Provide I I" x 17" PPP Exhibit. f. Sec. 6.E. — provide complete contact information. Only a name is listed. Provide address, tele., email, etc. (Note: Sec. 8 lists tel. # ; if this is tele.# of C. W. Dabney, list this tel.# at 6.E.) g. Sec. 9 /SIGNED CERTIFICATION: Sign certification. h. Sec. 11: Include 2019 VPDES CGP in SWPPP, since CGP applicable. B. Pollution Prevention Plan (PPP) — Also, item 2.e. above. (Rev. 1) Addressed. The PPP content requirements can be found in County Code section 17-404. 3. Provide I I" x 17" PPP Exhibit to include: a. Rain gauge. b. On -site fuel storage for construction grading equipment, if proposed (defer to design judgement). If shown, provide secondary (berm) containment with impermeable liner with volume sufficient to accommodate volume of stored fuel + 10-yr, storm event (vol.) x 1.1. (Rev. 1) Aoolicant: `Please note that there will be no fuel storage for the project on -site.' c. Stone construction entrance. d. Ex. pond dewatering device. Engineering Review Comments Page 2 of 5 e. Porta-john. C. Stormwater Management Plan (SWMP) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is approved. 1. Project does not qualify for any VSMP exemption listed at Sec. 17-303, A.-H., and is subject to the VSMP (Sec. 17-302.A.). This item discussed with and confirmed by County Engineer. 2. Revise sheet 1 plan title to read VSMP plan for 2435 Gobblers Ridge Pond. Include reference to 3. Submit VSMP Application with appropriate fee. The fee for small construction activity or land clearing that is equal to or greater than 1 acre and less than 5 acres is $2,700 (17-208). Note: this land -disturbance occurs on a single-family parcel, but land disturbance does not involve construction of a sole single-family detached dwelling. Project is ineligible for Agreement in lieu of a SWM Plan. 4. $300 received for VESCP may be applied to the VSMP permit fee. 5. Since half the $2,700 fee is due with initial application, balance pending is $1,035, Engineering will notify Intake staff of this circumstance. 6. This project requires and will receive a 2019 CGP. 7. Provide required VSMP Stormwater quantity and quality compliance calculations. Submit VaRRM.XIs. 8. Note: Engineering has considered Stormwater quality (sample VaRRM.xls, Attached) and quantity. a. SWM water quantity control should be relatively straight -forward: post -developed sheet flow that meets 9VAC25-870-66.D. Engineering accepts this provided plan demonstrates rill erosion unlikely. Also, ESCP review item #7, below. (Rev. 1) Addressed. Applicant: `Acknowledged and thank you for the provided VRRM. Please see analysis on sheet 7 that shows rill erosion unlikely due to intentional grading patterns.' b. SWM water quality phosphorus reduction requirement is _ ( $0) if use re -development worksheet (D soils, accurate for site), and 0.2 Ac. impervious (pre -developed; pond surface); that is, no SWM facility or water quality compliance measures required. Engineering accepts this. c. Recommend include USDA Websoil survey data with plan re -submittal (data attached). (Rev. 1) Addressed. Applicant: `USDA web soil survey data is included within the erosion control narrative. The soils data map is included on existing conditions.' 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 approved. Grayscale indicates a comment is addressed; virtually all comments were addressed with Rev. 1. [ Note: County email, 11/16/2020 1:48 PM requested a single label, and clarification concerning one item. Applicant provided Rev. la). ] Sheet 3 1. Sediment Trap a. ST Calculation table provides dimensions, which is helpful. Please also include ST floor dimension in plan view. b. Revise contours at ST weir, consistent with ST Calc, table. c. Provide dimension label for weir (L x W) and riprap downslope of weir ( L x W x D). (Rev. 1) Partially addressed. Applicant response (10/23/20 letter): `No riprap is proposed downstream of the sediment trap weir.' County email, 11/16/2020 1:48 PM, requests label. (Rev. la) Addressed. 2. Provide TSD (VESCH 3.15, to be abandoned once grading complete) to convey slope runoff since proposed grading eliminates existing permanent drainage channel. During construction, concentrated runoff conveyance, top to toe of slope, is required. This may outlet at the temporary ST and be covered in place with final stage of construction if inlet at top of slope is permanently closed. Albemarle is not Engineering Review Comments Page 3 of 5 directing design, but requests design consider and accommodate loss of existing permanent drainage feature that presently feeds the pond. Post -construction design proposes sheet runoff. It is grading phase operations that require temporary conveyance of storm runoff across and down the site, else periodic storm runoff may erode newly graded slopes. 3. Sheet 3, or 4: Provide topsoil note describing design intent (topsoil limits, depth) such that final graded slopes support permanent vegetation. Import does not need to be entirely topsoil, but suitable fill. Final graded slopes require topsoil to support permanent vegetation, and limit potential for downslope off -site impacts. (Rev. 1) Addressed. Applicant: `A note has been added on Sheet 4 to ensure that the top layer of fill is 2-4" of topsoil to ensure vegetation establishment in accordance with VESCH specification 3.30 Topsoiling.' 4. If pond floor sediment or sediment trap floor sediment is to be wasted on -site, discuss and show areas this saturated material will be wasted, or where and how it will be placed (on native, poor hydric, D soils) to drain sufficiently to support overlying layers of soil, without failure. (Rev. 1) Addressed, Applicant: The pond floor sediment is to be dried and spread with the topsoil layer in order to ensure the soil is not used in a loadbearing manner. A note has been added to sheet 3 to this effect.' a iy �'� T.M • 'P NSF FULLER, '� RNN s 1 '� � I .■ i I Sheet 4 5. Show proposed contours 384' 388'. (Rev. 1) Addressed. Applicant: `There is no proposed 384 contour on the final grading plan. The existing 388' that represents the top of the downslope side of the dam is now shown as proposed in the final grading plan (ESC phase II). The intent is that when the weir is removed the grade is restored to existing in that location.' Engineering Review Comments Page 4 of 5 �W • • DB4 W-NSF x/i imae s�cvw�.wiE rv¢occ ■ '� �„ p.n T.M N/i CIA© ®' DR' • ■ t i.M. 93-2X DB19p0/500 N/F BEpWF, DERER ERRIN \-- DR WINE TALE REDV.T \ 6. Display graphically outlet for water pumped from pond. a. Evaluate natural channel to receive pond pump water. (Rev. 1) Addressed. Applicant: `See flow rate calculation in same inset referenced above. The contractor provided a data sheet from the pump plan he plans to use. The max flow rate of 170 gpm is equivalent to 0.38 cfs. The flow rate is expected to be even lower given the flowpath through the dewatering bag, modified straw bale pit, and rip rap outlet. Additionally, the flow rate from the pump is significantly smaller than the existing 1 year peak flow rate to the same location.' b. Ensure volume and velocity of water thru natural receiving channel will not cause damage or exceed drainage capacity or contribute to downstream erosion or flooding. Note: Nearly immediately, pond pump water will discharge to neighboring property. c. Provide downstream and off -site ESC measures, as needed, to ensure even short duration effects of pumping cause no downstream /off -site erosion. (Rev. 1) Addressed. As follow-up: County email, 11/16/2020 1:48 PM, requests clarification /confirmation that all ESC measures intended to be shown on sheet 4 are shown. (Rev. la) Addressed via telecon with Applicant. No plan revision required. d. Show temporary ESC measures, as needed, in conjunction with a, b, c, above. e. Provide detail for dirt bag, or similar pond pump -water filtering device. f Provide detail for dewatering measure, or measures. g. Silt -laden pond pump -water may not be discharged directly to natural receiving stream or drainage feature. Provide narrative and propose measures to aid review, and compliance during construction phase, especially compliance with ESC Min. Std. 19, listed on sheet 5. 7. Evaluate post -development design storm runoff event. Ensure runoff from proposed grading is sheet runoff that will not likely cause or develop rill erosion. 8. Identify off -site borrow area, if borrow area known. (Rev. 1) Addressed. Applicant: `Off -site borrow area is not currently known. The operator is unable to identify a borrow area prior to plan approval.' 9. Provide ESC plan for off -site borrow area, if required. (Rev. 1) Addressed. Applicant: `A note has been added on sheet 1 that any offsite borrow must come from a location covered under an approved ESC plan.' 10. Sheet 5: Provide brief narrative project description. Identify borrow location. Recommend estimate volume of import required. (Rev. 1) Addressed. Applicant: `See the expanded project description on sheet 5. The borrow location is not currently known. An estimated volume of import is provided in the description (15,OOOCY).' Links: d. VSMP Application: httl)s://www.albemarle.org/home/showdocument?id=170 Engineering Review Comments Page 5 of 5 e. SWPPP: https://www.albemarle.org/home/showdocument?id=166 f. 2019 VPDES CGP (include at SWPPP, Sec. 11): https://www.deq.vir ig nia.gov/Portals/0/DEO/Water/StormwaterManagement/CGP%20ADA/CGP 2019.pdf?ver=2019-05-06-131630-407 g. 2019 VPDES Registration Statement (include at SWPPP, Sec. 1): https://www.deg.virginia. gov/Portals/0/DEQ/Water/StormwaterManagement/CGP%20ADA/CGP %20Registration%20Statement%202019 FINAL 201904.pdf?ver=2019-05-01-163955-110 Note: this project will be registered with DEQ Also, county email request for print plans (x 4) /print SWPPP ( x 2), 11/18/2020 8:28 AM. Process: After approval, plans will need to be bonded [ this is in process J. 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 Attomey and County Engineer. This may take 2-4 weeks to obtain all the correct signatures and forms. 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 (SWPPP Registration Statement). 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, the County can hold a pre -construction conference. Applicants must request a pre - construction conference (complete form) and pay any remaining application fee. The form identifies the contractor and responsible land disturber, and 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 under engineering applications at: https: //www.albemarle. oreleovemmenVcommunity-develooment/apoly-for/engineering-applications Please Note: Albemarle County website was redesigned/relaunched 8/10/2020. Certain links may not work —please let us know of any issues with the website. Please feel free to call if any questions. I may be reached at 434.296-5832 -x3069 Thank you. "'P0202000042_2435 Gobblers Ridge Pond VSMP rev l a_Approv 111720