SW3201003_Response to NCDEQ SW3201003_Add Info Request_20201215_20210305

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
BRIAN WRENN
Acting Director
Vincent G. Keene, PE
Yarbrough -Williams & Houle, Inc.
P.O. Box 1198
Pineville, NC 28134
NORTH CAROLINA
Environmental Quality
December 15, 2020
Subject: Request for Additional Information
Stormwater Permit No. SW3201003
Auto Finance & Car Care Center
Union County
Dear Mr. Keene,
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on October 28, 2020. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
Please revise Page 1 of the SWU-101 form to specify the county in which the project is
located. Revised Per Comments.
2. The receiving stream specified in the table on Page 3 of the SWU-101 application is
incorrect. Please use the Surface Water Classification Map to identify the proper
receiving stream. Revised Per Comments.
Please delineate all wetlands and streams on site or add a note that none exist [15A
NCAC 02H .1042(2)(g)(iii)]. Wetlands are now shown on plans.
4. The entire bottom of the sand chamber must contain sand. The calculations and design
provided are based on the previous version of the Stormwater Management Rules and
Stormwater Design Manual. The project must meet the standards of the current MDC and
Design Manual. Revised Per Comments.
5. Detail "A" on Sheet 11 specifies "3 layer of washed, non -clay sod, pea gravel, or washed
stone." Sod is not acceptable on a sand filter because of the possibility of clogging.
Please remove the reference to sod. Gravel or stone are acceptable on top of the sand
layer. Revised Per Comments.
6. The forebay volume stage -storage calculations are incorrect between El. 686 and 687 and
significantly overcalculate the storage volume of the sediment chamber.
Spreadsheet has been modified to show corrected storage volume.
D North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
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512 North Salisbury Street 1 1612 Mail Service Center I Raleigh, North Carolina 27699-1612
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7. Please show the building downspout connections on the grading and drainage plan.
Downspouts are now shown on Grading and Drainage plans.
8. Please provide calculations that show that the inlet to and outlet from the sand filter are
sufficiently designed to prevent erosion from the peak flow from the 10-year storm event
(General MDC 4). Inlet - RipRap sizing and calculations are provided at end of calc package
Outlet - Outfalls into existing storm drain.
9. Please show a maintenance access and easement that meet the requirements of General
MDC 8 & 9. Added and labeled on plans.
10. Provide pdfs of all revisions, 2 hardcopies of revised plan sheets, and 1 hardcopy of other
documents. Pdfs must be uploaded using the form at:
https://edocs.deg.nc.gov/Forms/SW_Project Submittal
Please note that this request for additional information is in response to a preliminary review.
The requested information should be received by this Office prior to January 14, 2021, or
the application will be returned as incomplete. The return of a project will necessitate
resubmittal of all required items, including the application fee. Please reference the State
assigned project number SW3201003 on all correspondence.
If you need additional time to submit the information, please submit your request for a time
extension to the Division at the contact below. The request must indicate the date by which you
expect to submit the required information. The Division is allowed 90 days from the receipt of
a completed application to issue the permit.
The construction of any impervious surfaces, other than a construction entrance under an
approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and is subject
to enforcement action pursuant to NCGS 143-215.6A.
If you have any questions concerning this matter please feel free to contact me at
Corey.Anengncdenr.gov or [phone]. Please note that due to the ongoing Covid-19
pandemic, I will be teleworking and will be most easily reached by email.
Sincerely,
Corey Anen
Environmental Engineer
Stormwater Program
cc: Mooresville Regional Office