SW3190803_Add Info_20190913

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. DANIEL SMITH
Director
Matthew I. Grant, PE
2351 Simonton Road
Statesville, NC 28625
NORTH CAROLINA
Environmental Quality
September 13, 2019
Subject: Request for Additional Information
Stormwater Permit No. SW3190803
Salem Leasing Corporation
Iredell County
Dear Mr. Grant:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on August 14, 2019. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
1. Since the applicant is the property owner, Section III, 2a & b are not required.
2. The river basin that this project is located in is the "Yadkin Pee Dee" basin (Section IV,
3). "South Yadkin" is the 8-digit subbasin.
3. Please clarify the total property area calculations (Section IV, 4 - 7). Item 7 (11.7 acres)
should not be larger than item 4 (10.725 acres).
4. Ensure that Section IV, 8 is calculated correctly, reflecting any changes made to item 7
from the prior comment.
5. Based on the provided contours, it appears that there will be some off -site areas draining
onto your site, Delray Street for example. Please include all off -site areas that will drain
to the proposed SCM in the drainage area table (Section IV, 10 & 11).
6. Please provide the original, signed copy of the Supplement-EZ form (Section V &
Section VI, 3).
7. A single signed application was provided with this submittal. We require that the
original application and a copy of the signed application be provided. Please provide a
copy of the signed application with your next submission (Section VI, 1).
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
NORTH CAROLINA _
o.PaWnamofEnvironmental Quality /� 919.707.9200

8. Please provide signed, sealed, and dated design calculations (Section VI, 7). Calculations
should include, but are not limited to:
a. Calculations showing how the design volume for the wet pond was determined
(General MDC 1).
b. Calculations showing that the inlet of the wet pond is sufficient to prevent erosion
during the peak flow from the 10-year storm (General MDC 4).
c. Calculations showing that the wet pond is sufficiently sized, using either the HRT
or SA/DA method (Wet pond MDC 1).
d. Calculations showing that the average depth of the wet pond is between three and
eight feet (Wet pond MDC 2).
e. Calculations showing that the forebay is adequately sized (Wet pond MDC 5). A
stage -storage table for the forebay, like the one provided for the main pool, will
suffice.
f. Calculations showing that the wet pond draws down the design volume between
two and five days (Wet pond MDC 7).
g. Calculations for the anti -flotation block sizing.
9. Please dimension all of the proposed BUA on sheet C3, similarly to how the office and
shop are (Section VI, 8, j). These values should correspond to the values used in the
drainage area table and Supplement-EZ form.
10. 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, 8, m).
11. Please show the drainage area for the SCM on the plans (Section VI, 8, o).
12. Please provide a soils report with the Seasonal High Water Table (SHWT) elevation
indicated as well as an NRCS soils map (Section VI, 9).
13. Property owner authorization is not required since the applicant is the property owner
(Section IX).
14. Please have the applicant sign and notarize the application in Section X.
15. Please correct the following issues with the Supplement-EZ form:
a. Cover Page
i. Line 2 — Ensure this value is correct.

b. Drainage Areas Page
i. Line 16 — Ensure that the "Entire Site" column is for the entire site and the
"1" column is for the area that drains to the wet pond. For example, if
there are sections of pervious property area that do not drain to the wet
pond (Like the section of the site adjacent to the PIN: 4724-87-5616
property) they should not be accounted for in the "1" column.
ii. Line 19 — Design volume is calculated using either the "Simple Method"
or the "Discrete NRCS Method".
c. Wet Pond Page
i. Line 5 — The side slope should be that of the above -water embankment of
the pond.
ii. Line 8 — The riser structure appears to have overflow/bypass features for
storm events larger than 1".
iii. Line 15 — Please indicate "Yes" or "No" for this item.
iv. Line 23 — Permanent pool elevation shown here (898) does not match
plans (899.5). Please revise for consistency.
v. Line 25 — Temporary pool elevation shown here (900) does not match
plans (900.5). Please revise for consistency.
vi. Line 26 — Please use the permanent pool surface area. This value should
match the provided stage -storage table.
vii. Line 27 — This value should match the provided stage -storage table.
viii. Line 33 — The forebay volume (3090 cf) is more than 20% of the main
pool volume (15102 cf). 3090 cf / 15102 cf = 20.46% > 20%
ix. Lines 36, 38, & 39 — The temporary storage volume is drawn down via an
orifice so the weir information does not need to be included.
x. Line 42 — Please indicate the bermsibaffles on the plan sheet.
16. Please include a maintenance access and easement on the plans (General MDC 8 & 9).
17. Sheet C3-1
a. Please indicate the cross -slope and width of the vegetated shelf on the cross-
section.
b. Please label the contours on the wet pond plan view.
18. 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:
hgps://edocs.deq.nc.gov/Forms/SW Project Submittal
While it is not required, it is recommended that:
- An emergency spillway be added to the wet pond. While the wet pond is designed to
handle the 100-year storm event, a more intense storm or a malfunction in the outlet
could cause embankment overtopping and the pond to fail catastrophically.
- The width of the maintenance access be increased to 25 feet as wet ponds generally
require larger maintenance equipment.
- Either the wet pond or existing pipes be relocated to avoid a conflict. Replacing and/or
maintaining these pipes will be much more difficult if they are buried under the
supporting slope of the wet pond.

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 October 13, 2019, 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 SW3190803 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,
V✓vl
Jim Farkas
Environmental Engineer
Stormwater Program
cc: Mooresville Regional Office