SW6110103_Add Info_20230112

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
DOUGLAS R. ANSEL
Interim Director
AECOM
Attn: Brian Fisher, PE
10 South Jefferson Street, Suite 1600
Roanoke, VA 24011
AND
NORTH CAROLINA
Environmental Quality
January 12, 2023
Fort Bragg Directorate of Public Works Environmental Division
Attn: David Heins, Environmental Division Chief
2175 Reilly Road Stop A
Fort Bragg, NC 28310-5000
Subject: Request for Additional Information
Stormwater Permit No. SW6110103
JSOC, SOF C4 Facility (LI66362) and Microgrid Installation & Integration
Cumberland County
Dear Mr. Fisher and Mr. Heins:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on October 18, 2022. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
1. Please ensure that the proposed SCM is sized/designed based on the actual drainage area
to the SCM. Per 15A NCAC 02H .1003(3)(b), any off -site or existing BUA that is not
bypassed around the SCM must be accounted for in the sizing of the SCM. For example,
based on the provided information for the proposed bioretention cell, the drainage area to
the SCM is approximately 0.54 ac and contains about 16,443 sf of BUA (from DAs A.1
& A.2, including existing BUA). This is different than the drainage area of approximately
0.61 ac and BUA of approximately 0.28 ac for this SCM that is shown in the Application
and Supplement-EZ Form. Please revise as needed.
2. Please clearly delineate the drainage areas to the SCMs in the main set of plans. This item
is required per 15A NCAC 02H .1042(2)(g)(iv). It is noted that the drainage area to the
downstream culvert is shown in the plans, however, the drainage area to each individual
SCM must be shown in the plans. NOTE: An off -site component of an SCM drainage
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area is an area that drains to the SCM but is located outside of the project area. For
example, drainage area A.3 would not be considered an off -site part of the drainage area
to the proposed bioretention cell since it does not drain to it. Any areas like drainage area
A.3 would be accounted for in the "Entire Site" column on the Drainage Areas Page of
the Supplement-EZ Form.
3. Please provide the existing ground surface elevation for the SHWT boring (Bioretention
Cell MDC 1). It is noted that the depth from the existing ground surface elevation to the
SHWT (or in this case, the lack of SHWT indicators) is provided, however, without the
existing ground surface elevation for this boring, we cannot determine the elevation of
the SHWT and cannot verify adequate separation between the bottom of the bioretention
cell and the SHWT.
4. Plan sheet CG501 has callouts indicating the presence of outlet protection for the inlet
into the bioretention cell and outlet out of the bioretention cell but the plans do not
indicate the presence of outlet protection and the sizing calculations for outlet protection
were not provided. If outlet protection is not needed, please remove the references to
outlet protection from the plans and indicate that calculated flows are nonerosive in the
calculations. If outlet protection is needed, please show it on the plans and provide the
sizing calculations. This item is required per General MDC 4.
5. While not required, it is noted that ponding in the bioretention cell will back up into the
grass swale during design storms and will nearly overtop the adjacent roadway during
larger storm events (see attached). It is strongly recommended to either design the SCM
to be off-line (so that larger storm events are bypassed before entering the SCM) or to
include an emergency spillway to prevent structural failure of the roadway and
embankment during large storm events.
6. Please correct the following issues with the Supplement-EZ Form:
a. Cover Page:
i. Line 7 —Please include this item (15A NCAC 02H .1003(4) & .1017(10)). It is
noted that there are no surface waters located on -site, however, we ask that this
information be included. Lines 8 & 9 can be left as "N/a" since there are no surface
waters located on -site.
b. Drainage Areas Page:
i. Entire Site Column:
1. The entire site column is an accounting of the entire project area, not just a
sum of the other columns. Any BUA located within the project area (whether
or not it drains to an SCM) should be accounted for in this column and the
"drainage area" for the entire site column is equal to the project area. While not
required, you can add bypass or "Site 1" & "Site 2" columns to help clarify
things if you wish (The information provided in the calculations was very
through and well put together, unlike our forms). If the form is unclear, please
let me know, we can set up a meeting to discuss.
2. Lines 4, & 19-21 are not required for the entire site column.
ii. Please revise the other columns as needed.

Bioretention Cell Page:
i. Line 2 — Please revise as needed. This value should be calculated based on the
actual drainage area to the SCM.
ii. Line 12 — Please clarify this point in the Additional Information (Line 44).
Typically, projects require this item, but since this project is located at Ft. Bragg, it
is not required.
iii. Line 18 — Revise if needed.
iv. Lines 34 & 35 — There is an error in the Manual with regard to the mix
percentages. Please refer to 15A NCAC 02H .1052(6)(b)&(c). NOTE: The mix
percentages appear to be correct on the plans.
v. Line 36 — Please clarify/elaborate on this in the Additional Information (Line 44).
d. NOTE: The DWQ Supplement Form is not required.
7. Provide PDFs of all revisions, 2 hardcopies of revised plan sheets, 1 hardcopy of other
documents, and a response to comments letter briefly describing how the comments have
been addressed.
a. PDFs must be uploaded using the form at:
https:,[/edocs.deq.nc.gov/Forms/SW-Supplemental-Upload
b. Hard copies must be mailed or delivered to the following address:
i. For FedEx/UPS:
Jim Farkas
512 N. Salisbury Street, Office 640M
Raleigh, NC 27604
ii. For USPS:
Jim Farkas
1612 Mail Service Center
Raleigh, NC 27699-1612
iii. Hand Delivery:
Please reach out to me prior to hand delivering a submission to make sure that I
(or someone else in my group) will be able to receive the submission. Do not
leave the package in the foyer with the security guard.
NOTE: Hard copies should not be sent to a Regional Office. Doing so will delay
the review process and the submission package may be lost while being sent from
the Regional Office to me in the Central Office.
While it is not required, it is recommended that the off -site drainage from upstream properties be
diverted around the SCM since the Applicant cannot maintain control over the development of
property that they do not own. If the Applicant elects to account for off -site drainage, it must
either be accounted for as 100% BUA (its full build out potential), or there must be a recorded
legal agreement in place between the Applicant and the Owner of the upstream property in which
the Owner of the upstream property agrees to record a deed restriction limiting the
minimum/maximum amount of BUA on the upstream property that will be treated in the

Applicant's SCM, the locations and sizes of access and drainage easements, how construction
and/or ongoing maintenance costs will be handled, maintenance responsibility, a list of legal
recourses available to each party should one party fail to hold up their end of the agreement, and
any other related legal issues.
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 February 11, 2023, 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 SW6110103 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,
Jim Farkas
State Stormwater Engineer
DEMLR Post -Construction Stormwater Program
cc: Fayetteville Regional Office