SW6200102_Add Info_20200508

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
BRIAN WRENN
Acting Director
F. Michael Mayer, PE
300 W. Vine Street Suite 1300
Lexington, KY 40507
NORTH CAROLINA
Environmental Quality
May 8, 2020
Subject: Request for Additional Information
Stormwater Permit No. SW6200102
Human Performance Training Center (PN 79443)
Cumberland County
Dear Mr. Mayer:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on April 4, 2020. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
Original Comment 3 — "Please delineate the wetlands on the plans or provide a note
stating that no wetlands exist. Provide documentation of the qualifications and identity of
the individual who made this determination (Section VI, 8m). " It is noted that the wetland
delineation and determination is included in the stormwater management report.
However, this information must be included on a plan sheet (It is possible that I may have
overlooked this information in the plan set during my review. If I did, please let me know
on which plan sheet the information can be found).
2. Original Comment 5 — "The proposed facilities are undersized and do not fully meet the
treatment requirements for this project (General MDC 1). Per the Stormwater Design
Manual (Guidance under Bioretention MDC 2), the minimum bioretention surface area is
determined by dividing the design volume by the ponding depth (i.e. storage in the filter
media is not counted toward the design volume). Please provide sizing calculations for
the design volume for the 1 " storm (Section VI, 7). " There is discrepancy between
information used in the provided design volume calculations and information shown in
the Application/Supplement-EZ Form/Report. One such example is that the Application
and the report (Appendix C) shows proposed drainage area 1 as 2.58 acres while the
calculations (Appendix H) shows the total drainage area as 2.07 acres. Ensure all
calculations and information is consistent.
3. Please correct the following issues with the Supplement-EZ Form:
D E Q2� North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
512 North Salisbury Street 1 1612 Mail Service Center I Raleigh, North Carolina 27699-1612
NORTH CAROUNA -
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a. Cover Page:
i. Provide an original, signed in pen, hard copy of the cover page.
b. Drainage Area Page:
i. Line 15 — There does not appear to be any existing BUA within either of
the drainage areas or project site (Per satellite imagery and plan sheet
CG750). Please either label (with callouts showing the area in sf) existing
BUA on sheet CG750 or revise the submittal information to remove the
existing BUA. It is also recommended to add impervious/pervious
breakdowns under each drainage area note on sheets CG750 & CG751. If
there is existing BUA within the site/drainage area, it should be reported
on Line 13 (even if it will be removed/replaced).
ii. Entire Site Column, Line 16 — This value should coincide with the value
from Section IV, 8.
c. Bioretention Sheet:
i. Line 18 — See earlier comment.
4. Soil borings B 1 — B4 indicate that the SHWT elevation is less than two feet below the
lowest point of the bioretention facilities (The lowest excavated elevation of bioretention
cell 1 is at elevation 252.5 and the SHWT elevation at boring B3 is at elevation 256.35.
The lowest excavated elevation of bioretention cell 2 is at elevation 254.5 and the SHWT
elevation at boring B2 is at elevation 257.0. NOTE: The highest SHWT elevation within
the SCM footprint should be used for these comparisons, not the lowest). Please do one
of the following:
a. If you believe that the SHWT elevation findings presented in Appendix IV of the
April 2, 2019 Report of Subsurface Exploration and Geotechnical Engineering
Evaluation are incorrect (Due to a perched water table or any other reason), you
will need to provide a more recent and more comprehensive SHWT investigation
and report disputing the SHWT elevation claim in the April 2, 2019 report. Part
A-2 of the Manual has more information on SHWT separation.
b. Redesign the SCMs so that at least 2 feet of vertical separation is present between
the lowest excavated point of the bioretention cells and the highest SHWT
elevation reading (Boring B3 for bioretention cell 1 and boring B2 for
bioretention cell 2).
5. NOTE: Per Division policy, the next review of this application will be the final review.
Failure to provide the requested information will result in the project being returned as
incomplete. The return of a project will necessitate resubmittal of all required items,
including the application fee.
6. 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.deq.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 June 8, 2020, 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 SW6200102 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: Fayetteville Regional Office