The URL can be used to link to this page

Home My WebLink AboutWPO202100057 Review Comments WPO VSMP 2021-11-12�$ County of Albemarle m COMMUNITY DEVELOPMENT DEPARTMENT VSMP Permit Plan Review Project title: Pantops Shopping Center - Enterprise Car Wash Project file number: WP0202100057 Plan preparer: Collins Engineering [scott@collins-engineering.com] Owner or rep.: CHARLES ROTGIN JR and Pantops Shopping Center, LLC Plan received date: 12 Oct 2021 Date of comments: 12 Nov 2021 Reviewer: Emily Cox 401 McIntire Road, North Wing Charlottesville, VA 22902-4579 Telephone: 434-296-5832 WWW.ALBEMARLE.ORG 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/disapproved. The rationale is given in the comments 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. 1. Please provide a signed registration statement. 2. Plans in SWPPP will need to be updated with the final, approved plan. 3. Please provide a signed certification (Section 9). 4. There appears to be two TMPs and two owners associated with this project. They will both need to sign all associated documents. 5. Please provide the owners email addresses. B. Pollution Prevention Plan (PPP) The PPP content requirements can be found in County Code section 17-404. 1. Please provide a plan view sheet of the PPP in the SWPPP. 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. A SWM Agreement must be recorded before this plan can be approved. Please contact Ana Kilmer[akilmer@albemarle.org or 434-296-5832 x3246] to complete this process. 2. Nutrient Credits must be purchased before this plan can be approved. Please contact Ana Kilmer[akilmer@albemarle.org or 434-296-5832 x3246] to complete this process. Engineering Review Comments Page 2 of 4 3. Will this area be addressed? It appears to be included in the limits of your project (gets some drainage from the utility installation and some sheet flow): 4. Limits of preserved slopes on this plan do not appear to match those shown on County GIS. To change these, you must submit a signed and sealed survey exhibit per County Code Sec. 30.7.4- b.1.h. 5. Where is the car washing activity going to occur? Please show where the wash water will be collected. 6. Drainage area appears to be different than limits of construction. Please clarify and show the drainage areas used for water quantity calculations. There is some sheet flow from the existing parking lot. It is understood that the VRRM area is only the area that is disturbed. 7. Please show where the existing roof drains from adjacent buildings outlet. 8. Will there be a final site plan for this? If not, the easements must be recorded and the wall designs must be provided before this plan can be approved. Also, an initial site plan or LOR must be submitted/approved before WPO can be approved. 9. Is there an existing easement on this ouffall? 10. Any work to this outfall above would require a floodplain development permit. Also, per your note, you must specify the type/size of rip -rap proposed. 11. Please show the 100-ft stream buffer. 12. Please show the floodplain elevation. 13. Please show that the existing pipe you are connecting to is adequate. You must include the flow through that pipe in your analysis. An example of how to do this with energy balance is attached to this comment letter (from the DEQ plan reviewer class). Engineering Review Comments Page 3 of 4 14. A video of the existing pipe to the outfall should be completed to show that it is currently in good condition. 15. Provide pipe calculations from the SWM to the outfall. Other onsite pipes can be provided with final site plan(if there is one). 16. Please provide a cross section of this area: L=44', S=1.14% � O Ensure the grading meets county code: 18-4.3.3, especially the distance to the property line. 17. Please provide a detail of the proposed retaining wall. 18. It appears guardrail is necessary along the retaining wall and slope. Please provide a detail. 19. Per County Code 18-4.12.17, the minimum one-way drive aisle width is 12ft. Please show this dimension. 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/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. 1. Limits of disturbance are very close to preserved slopes, especially near the retaining wall. Please show cross section and wall tie back locations to show that preserved slopes will not be disturbed. 2. Please specify plantings that can withstand steep slopes for those that are steeper than 3:1. 3. There should be perimeter controls for this area: PU Engineering Review Comments Page 4 of 4 4. Please address the fill in the sequence of construction. Will any measures have to be moved as the site is constructed. Will slope drains be necessary? 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. Process: After approval, erosion and sediment control and stormwater management improvements must be bonded. The bonding process begins when the plan is approved, and the applicant submits a bond estimate request form and fee to the Department of Community Development. A plan reviewer 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 to the County, who will record the agreement. After bonding and agreements are complete, county staff enters project information in a DEQ database for state application processing, if a DEQ permit is required. DEQ reviews 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, which must be posted at the construction site. After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction conference. Applicants must 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; https://www.al bemarle.org/government/commu nity-development/apply-for/engineering-applications 5d. Energy Balance and Run-on \ q,po,t = 1-year post -development peak discharge C RVlpre ` , q,p,e = 1-year pre -development peak discharge Rlpost � Rlpre J (IF) RVlpo RVlp,e =1-year pre -development runoff volume RV,w,t =1-Year post -development runoff volume IF = improvement factor When run-on or drainage from offsite areas is conveyed as concentrated flow through a post - development site, then this offsite Flow would contribute to the discharge from the site and be considered in the calculation of allowable discharge rate from the site outlet. When the Energy Balance equation is being used to determine the allowable discharge, the improvement factor would need only be applied to the "site" as per the regulatory language of 9VAC25-870.66.B.3.a. In this case, the application of Energy Balance to the discharge from the site would be calculated as follows: RVV1pre,site RV1pr ,offsite o glpst < glpresite (IF) + Qlpre,offsite R1pos sire RV1po ,offsite q,p.t- = 1-year allowable post -development peak discharge from site (includes offsite run-on) glpre- = 1-year pre -development peak discharge from site (q,pre,rlte) or offsite area (q,pre,of,;te ) RV,pre- = 1-year pre -development runoff volume from site (RV,po,c,ite) or offsite area (RVj,,t if:;te) RV,po,t- = 1-year post -development runoff volume from site (RV,pre,,;te) or offsite area (RV,pre,offs;te) IF= improvementfactor Module 5: VSMP Water Quantity Requirements Plan Reviewer for Stormwater Management (version 4.1) Page 36 Since �L-.-=!-^.-=r ��f run-on to site from offsite areas are equal, the equation becomes: RlVipre,site glpost < glpre,site (RVpos site (IF) + glpre,offsite , Offsite run-on: / ♦�Concentrated Conveyed through site No improvement �� 1 % 1# Alsite discharge: Include offsite run-on lowable Note: The assumption in the calculation above is that the site* equals the land -disturbing activity (LDA). The definition for "site" is not clearly defined in the regulations but LDAs are defined as regulated. The water quantity criteria are applied to the site as per the regulations. This nuance can be addressed by a VSMP authority on a case by case basis or as standard policy, although more stringent application of water quantity technical criteria should appear in local ordinances for locality VSMP authorities. _z„ Module 5: VSMP Water Quantity Requirements Plan Reviewer for Stormwater Management (version 4.1) Page 37