SW6230102_Response To Comments_20230504

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
DOUGLAS R. ANSEL
Interim Director
Larry King & Associates, PLS, PA
Attn: Jeffery Nobles, PE
1333 Morganton Rd, Ste 201
Fayetteville, NC 28305
WITFE
NORTH CAROLINA
Environmental Quality
April 13, 2023
H&H Investments, Inc.
Attn: D. Ralph Huff, III, Registered Agent
2919 Breezewood Ave
Fayetteville, NC 28303
Subject: Request for Additional Information
Stormwater Permit No. SW6230102
Tranquil Meadows, Phase I
Hoke County
Dear Mr. Nobles and Mr. Huff:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on January 17, 2023. 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 provide a calculation in the calculation booklet showing how the percent B L 1A for
the site is calculated (Section IV, 8 & 10). The percent impervious area for the project
area does not appear to be calculated correctly. Per 15A NCAC 2H .1003(1): (a) Project
density shall be calculated as the total built -upon area divided by the total project area;
Based on the provided information in the Supplement-EZ Form, the site is shown to have
978,799 sf of total BUA and in a project area of 2,785,226 sf. [(978,799 SF/2,785,226
SF)=35%>26%] Please also revise the Supplement-EZ form "Drainage Area Information
Table" Entire Site column.
a. Clarify the number of lots in Phase I of the project. Lots 1-123 and 135 are shown in
this plan. If 124 lots are being proposed with this plan, the BUA would be 396,800 SF
(124 lots* 3,200 SF/lot= 396.800 SF. It is noted that Lot 91 is the location of the mail
kiosks and associated parking and may not be intended to be part of the BUA on
North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
E 512 North Salisbury Street 1 1612 Mail Service Center I Raleigh, North Carolina 27699-1612
"++�'� 919.707.9200

Phasing has been revised from original submittal. Only areas shown as Phase 1 will be
constructed at this time. This will be 75 residential lots plus 2 mailbox kiosk lots. Only Basin 1 is
included. Everything shown in Phase 1 drains to Basin 1, but parts of the overall drainage area
subd for Basin 1 will be constructed with Phase 2.
the calculations, application, Supplement-EZ form.
2. Shrubs are not an acceptable planting for a stormwater wet pond. Please select
appropriate plants in accordance with 15A NCAC 02H .1053 (11). Plants list updated.
3. Please revise the grades from the top of the maintenance shelf to be at least 3:1 and revise
the associated cross section. Per 15A NCAC 02H .1050 (8), maintenance access shall not
include slopes that exceed 3:1. For Basin 1 the cut slopes along the top of the pond were already 3:1. The fill
slopes on the bottom of the pond have been revised to 3:1.
4. The shortest flow path of Stormwater Wet Detention Basin #1 is too short. Incorporate
design changes that would increase the flow path and prevent short circuiting (15A
NCAC 02H .1053 (4)). Baffles, inlet and outlet locations, or a change in dam height
could be utilized. Forebay berm top raised to temp pool elevation (223.70 to force flow
through overflow weir)
5. Please revise the Supplement EZ form for each SCM (Section V). Please note:
a. Cover: Line 7 — While there is no surface water, and therefore no vegetated setbacks
associated with this project, please fill in. Per 15A NCAC 02H . 10 17 (10), the
vegetated setback shall be at least 30 feet in width. 30' width noted on form
b. Wet Pond: Line 7 --- Please ensure, and provide calculations showing that, the inlets
and outlets are stable in accordance with General MDC 4. If protection cannot be
achieved, please provide calculations for appropriate erosion control (such as riprap)
and show on the plans. Wrong answer selected. Rip rap protection is provided at outlets. Calcs
c. Wet Pond: Line 16 — The SCM is required to follow device specific MDC per 15A
NCAC 02H .1050 (13) unless a variance is applied for. If a variance is desired, please
see the requirements in 15A NCAC 02H .1003 (6) and elaborate on the nature of the
variance and justification. Wrong answer selected from pulldown. Has been updated.
d. Wet Pond: Line 27 — In the provided stormwater calculations, there were incorrect
values in the "Elev. Diff' column, resulting in an error in the main pool volume.
Revise in the calculations, as well as the Supplement EZ form. The permanent pool
and main pool will need to be revised. The calculation has been updated. Avg Depth calc updated accordingly
e. Wet Pond: Line 34 — The cleanout depth is listed in the Supplement EZ form as 10
inches. which does not match the plans and calculations. The cleanout depth of the
forebay is the distance from the permanent pool surface elevation to the top of the
sediment storage zone. Depth updated.
f. Wet Pond: Line 52 — The dam and embankment are required to be planted in non -
clumping turf grass per 15A NCAC 02H .1053 (11). That is the intent. Wrong answer selected from
the pulldown options.
6. Please provide signed, sealed, and dated design calculations (Section VI, 7). Calculations
should include, but are not limited to:
a. Provide calculations or explanation of SA/DA value. Tables 10-1, 10-2, and 10-3
reference the 2006 SA/DA table used is Table 1 from the 4-18-1 t version of the manual. The be
found here: https:/, reference under the calculation simply had not been undated
resources/stormwater/stormwater-program/stormwater-design-manual
b. Forebay is oversized for Stormwater Wet Detention Basin #2. Forebay volume shall
be 15 to 20 percent of the volume in the main pool. 15A NCAC 02H .1053 (5) (a).
When the main pool volume is recalculated, it is approximately 54,538 cf based on
Basin 2 in no longer included with this submittal.

the values provided in the stage storage table. Therefore, I I.181 cf/ 54,538 cf=
20.5%>20%.
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:
-.'/edocs.deq.nc.gov/Forms/SW-Supplemental-Upload
b. Hard copies must be mailed or delivered to the following address:
i. For FedEx/UPS:
Brianna Holland
512 N. Salisbury Street, Office 640E
Raleigh, NC 27604
ii. For USPS:
Brianna Holland
1612 Mail Service Center
Raleigh, NC 27699-1612
ii I. 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 nacka2e 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, alternative layouts that would increase the flow path and prevent short
circuiting on Stormwater Wet Detention Basin #2 are recommended as the shortest flow path
was very close to being considered too short (15A NCAC 02H .1053 (4)). Baffles, inlet and
outlet locations, or a change in dam height could be utilized.
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 May 13, 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 SW6230102 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,
66a�� ko4a
Brianna Holland
State Stormwater Engineer
DEMLR Post -Construction Stormwater Program
cc: Fayetteville Regional Office