SW6200704_AddInfo_20210129

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
BRIAN WRENN
Director
Jeffrey A. Nobles, PE
1333 Morganton Road, Suite 201
Fayetteville, NC 28305
NORTH CAROLINA
Environmental Quality
January 29, 2021
Subject: Second Request for Additional Information
Stormwater Permit No. SW6200704
Cypress Pointe
Cumberland County
Dear Mr. Nobles:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on December 30, 2020. 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 4 — "Drainage Area I appears to have off -site components. Please
ensure that these off -site areas are accounted for properly (Section IV, 10 & 11). " Per
the "While it is not required" note near the end of the first Request for Additional
Information letter, off -site drainage areas either need to be accounted for at their full
build out potential (100% BUA) or there needs to be an agreement between property
owners limiting the amount of BUA within the off -site drainage area. Currently, the off -
site drainage area is shown to have 0 sf of BUA and was no agreement provided. Please
revise as needed.
2. Prior Comment 5 — "Please provide plan sheet C-01, `Existing Conditions Plan'
(Section VI, 8). Ensure that the project/property boundary is dimensioned (Section VI, 8i)
and that existing drainage conditions (Section VI, 8n) are included. These features can be
added to a new sheet if that is more convenient. " The existing conditions plan was not
provided in this resubmission.
3. Prior Comment 7 — "Do not forget to include the parts of the site that drain into the
proposed SCMs via overland flow in the SCM drainage areas (Section VI, 8o). You can
alternatively divert this area around the proposed SCMs. Either way, the surface areas of
the proposed SCMs should be included in their respective drainage areas as rain falling
onto the SCMs cannot be diverted around them. " Infiltration Basin 2 is undersized. Per
the surface area requirement calculations, the drainage area to Infiltration Basin 2 is
D EQ �� 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
NORh1 CAROIJNA �
919.707.9200

shown to be 18.31 acres while the Application, plans, and the design volume calculations
show the drainage area to this SCM to be 19.02 acres. Please revise as needed to ensure
adequate surface area is provided. You may wish to double check your drawdown/surface
area calculations as they seem off (It's (k*T), not (k+T)).
4. Prior Comment llbiil — "Please correct the following issues with the Supplement-EZ
Form, Drainage Areas Page, Entire Site Column: The information in this column should
be an accounting of the entire project area, not just a sum of the two drainage areas. If
there is any proposed BUA that is located outside of either drainage area (Such as the
connections to the main road), it should be accounted for in this column. " The total BUA
and New BUA values in this column should be larger than the sum of the respective lines
of the drainage area columns. There is some proposed BUA (parts of the entrance roads)
that does not drain to either SCM and would only show up in the entire site accounting.
NOTE: The net increase in BUA is required to be treated in one or more primary SCMs
in order to meet Runoff Treatment.
5. Prior Comment 12 — "Provide pdfs of all revisions, 2 hardcopies of revised plan sheets,
and I hardcopy of other documents. Pdfs must be uploaded using the form at:
https://edocs.deg.nc.gov/Forms/SW Project Submittal" Please make sure to provide two
(2) hard copies of the revised plans as only one was provided.
6. Please correct the following issues with the Supplement-EZ Form:
a. Drainage Areas Page:
i. Drainage Area 2 is not included, and it should be.
ii. Line 4 — The SCM for Drainage Area 1 is listed as a dry pond.
iii. Line 18 — This value (13,426 cf) is different than the value in the
calculations (13,716 cf). Please revise either or as needed for consistency.
b. Infiltration System Page:
i. Line 2, Drainage Area 2 — This value (27,690 cf) does not match the value
from the calculations (27,819 cf). Please revise either or as needed for
consistency.
ii. Line 4 — This item is required since it is an MDC. If the soils are
contaminated, you cannot use an infiltrating SCM to treat the stormwater.
iii. Lines 22 - 24, Drainage Area 1 — Please use the more conservative boring,
Boring #1, for the SHWT estimation at this SCM.
iv. Line 25 — Since the depth to the SHWT is greater than two feet for each
SCM, the detailed hydrogeologic study is not required.
v. Line 26 — These values differ form the infiltration rates as shown in the
soils report, however you can use these infiltration values if you like as
they are more conservative than the values in the soils report.
vi. Line 30 — Please show the temporary ponding surface elevation associated
with the design volume. If these cells do not allow/show the numbers after
the decimal place, please put the actual values in the "Additional
Information" (Line 46).

vii. Line 31 — Similar to the prior comment, make sure that these values are
consistent with the plans, using Line 46 if needed.
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. Off -site areas must either be accounted for in accordance with
15A NCAC 02H .1003 (3)(b) or through 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 28, 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 SW6200704 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
Environmental Engineer
Stormwater Program
cc: Fayetteville Regional Office