SW3190802_AddInfoRequest_20191015

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. DANIEL SMITH
Director
David Sherrill, PE
Pike Engineering, LLC
123 North White Street
Fort Mill, SC 29715
NORTH CAROLINA
Environmental Quality
October 15, 2019
Subject: Request for Additional Information
Stormwater Permit No. SW3190802
Trinity Electrical Substation
Union County
Dear Mr. Sherrill:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on August 7, 2019. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
The proposed design utilizes a significant amount of piping to drain the site. The low
density regulations at 15A NCAC 02H .1003(2)(c) only allow "a minimal amount of non -
vegetated conveyances for erosion protection or piping for driveways or culverts under a
road." Please revise the design to reduce the amount of piping to comply with this
requirement.
2. Please show the swales in an easement that conforms with General MDC 9 [15A NCAC
02H .1050(8)].
3. Please revise the Supplement EZ form to address the following deficiencies:
a. On the Drainage Areas sheet, please enter three for the amount of drainage areas
(question 2) and complete the form for each swale.
b. Please complete the Low Density sheet with the information for each swale and
calculations to show that they are designed to not erode during the peak flow from
the 10-year storm [15A NCAC 02H .1003(2)(c)(ii)].
4. Please provide calculations to confirm that the swales are designed with a hydraulic
retention time of 8 minutes, as shown in the Supplement EZ form [15A NCAC
02H .1061(3)].
D EQ �� North Carolina Department of Environmental Quality Division of Energy, Mineral and Land Resources
512 North Salisbury Street 1 1612 Mail Service Center Raleigh, North Carolina 27699-1612
NORTH CAROLINA
o.P.nm.morenmonm.maauaz /� 919.707.9200

5. 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:
hqps:Hedocs.deg.nc.gov/Forins/SW ProjectSubmittal
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 November 14, 2019, 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 SW3190802 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.Anen&ncdenr.gov or [phone].
Sincerely,
Corey Anen
Environmental Engineer
Stormwater Program
cc: Mooresville Regional Office