SW5210202_Add Info_20210507

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
BRIAN WRENN
Director
Blake Hall, PE
5410 Trinity Road, Suite 102
Raleigh, NC 27607
NORTH CAROLINA
Environmental Quality
May 7, 2021
Subject: Second Request for Additional Information
Stormwater Permit No. SW5210202
Franklin County E911
Franklin County
Dear Mr. Hall:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on April 5, 2021. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
Prior Comment 8 — "Please dimension the project boundary with bearings and
distances (Section VI, 8i). This information should be shown in the main set of plans.
Please show the entire extents of the project boundary (You may wish to add this
information to plan sheet C4.4).
2. Prior Comment 16a — "Provide pdfs of all revisions... Pdfs must be uploaded using the
form at: https:Iledocs.deg. nc.;?ov/Forms/SW Project Submittal" We did not receive the
electronic files for this submission. Please ensure that the files from the April 5th
submission and the files for the next submission get uploaded. Occasionally, the file
upload portal will stall (and not register the upload) if the files are very large.
3. There appears to be a discrepancy between the BUA information shown in the
Application/Supplement-EZ Form and as shown in the SIA calculations. In the
Application/Supplement-EZ Form, the drainage area to the wet pond is shown as 1.49
acres (64,812 sf) and the amount of BUA in the drainage area is shown as 0.60 acres
(25,934 sf). The SIA calculations show the drainage area to the wet pond as 1.48 acres
and the amount of BUA in the drainage area as 0.56 acres. Make sure that you are not
double counting Existing BUA.
4. The forebay volume appears to be incorrectly calculated in the SIA calculations. The
sediment storage area (below elevation 247') should not contribute to the volume of the
DNorth Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
EQ
_ 512 North Salisbury Street 11612 Mail Service Center I Raleigh, North Carolina 27699-1612
NORTH CAROLINA
Department oiEnvironmental aum� 0 ` 919.707.9200

forebay (the stage -storage table shows an incremental volume of 106 cf from elevation
246' to 247' ).
5. The provided stage -storage table for the main pool and forebay do not show the cross -
sectional areas or volumes up to the permanent pool (they stop at elevation 250.5'). this
was also mentioned in Prior Comment 12. Since the berm separating the forebay from the
main pool is below the permanent pool elevation an imaginary vertical line that runs
along this berm should be used to divide the main pool from the forebay (See image
below).
(A) (g)
Perm. Pool Elevation
INCORRECT
Perm. Pool Elevation
CORRECT
6. Please correct the following issues with the Supplement-EZ Form:
a. Drainage Areas Page:
i. Please complete the Entire Site Column. This column is an accounting of
all of the BUA for the entire site. The "drainage area" for the entire site
would be the project area and the "design storm" and "design volume" are
not required for this column.
b. Wet Pond Page:
i. Lines 2, 26-29, 32, & 35 may need to be changed, depending on earlier
comments.
ii. Line 34 — The cleanout depth of the forebay is the distance from the
permanent pool elevation (251') to the top of the sediment storage
elevation for the forebay (247'), expressed in inches.
iii. Lines 43 & 44 — The depth of the forebay is the distance from the
permanent pool elevation (251') to the excavated bottom of the forebay
(246'), expressed in inched. Some forebays are designed to have a sump
near the inlet pipe (See Figure 5 of Part C-3 of the Stormwater Design
Manual) in these cases, the two different depths would be recorded, but if
the bottom of the forebay is at a uniform elevation, then these two Lines
would be the same.
iv. Line 48 — Per the provided detail on plan sheet C4.2, the pond draws down
from below the permanent pool surface elevation.
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 June 6, 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 SW5210202 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
[e-mail] or [phone].
Sincerely,
)-6mGW�
Jim Farkas
Environmental Engineer
Stormwater Program
cc: Raleigh Regional Office