SW3191204_Add Info_20200121

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. DANIEL SMITH
Director
Steve Farmartino, PE
1927 South Tryon Street, Suite 310
Charlotte, NC 28203
NORTH CAROLINA
Environmental Quality
January 21, 2020
Subject: Request for Additional Information
Stormwater Permit No. SW3191204
Arka Heights
Union County
Dear Mr. Farmartino:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on December 20, 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. Please provide some form of documentation showing that KP Maganti is the president of
Arka Heights, LLC, or that they may sign on the behalf of Arka Heights, LLC (Section
III, la, Section VI, 11, & Section X). The provided Secretary of State LLC information
does not list KP Maganti.
2. The person listed as the property owner, Beautrice H. Barnette, does not match the person
signing on behalf of Barnette Store, LLC, Dennis W. Moser (Section III, 2a & Section
IX). Please revise for consistency.
3. Please recalculate the project density (Section IV, 8). The project density is the total BUA
in proposed conditions within the project area divided by the total project area.
4. Please correct the following issues with the table in Section IV, 10:
a. Please provide the stream classification for each drainage area.
b. Please provide the stream index number for each drainage area.
c. Please report the total drainage areas and on -site drainage areas in square feet.
d. Please use exact BUA values for this table.
e. The surface area of the wet ponds does not need to be accounted for in the "other
on -site" row.
f. Please include the existing BUA.
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

5. 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).
6. While it is appreciated and helpful to have the SCM drainage areas included in the
stormwater calculations, the drainage areas for the wet ponds must also be shown on the
plans (Section VI, 8o).
7. Please provide the stormwater soil borings, SW-1 and SW-2, that are mentioned in the
geotechnical report (Section VI, 9).
8. Since the wet ponds are connected via a 0% slope equalizing pipe and wet pond 2 does
not have an outlet/riser structure, the two wet ponds should be treated as a single wet
pond in the Application and supporting documents. When providing stage storage tables
for the combined wet pond, please have a column(s) for the west portion of the wet pond
(indicated with a "W" in the table below) and a column(s) for the east portion of the pond
(indicated with an "E" in the table below). Please refer to the illustrative example below.
Essentially, the two stage -storage tables will be added together.
Elev.
(ft)
W. Area
(sf)
W. Inc.
Stor. (cf)
W. Tot.
Stor. (cf)
E. Area
(sf)
E. Inc.
Stor. (cf)
E. Tot.
Stor. (cf)
Tot.
Stor (cf)
100
321
100
100
123
50
50
150
101
654
200
300
456
150
200
500
102
987
400
700
789
350
550
1250
9. Please refer to the Stormwater Design Manual, sections C-0 and C-3 for the Minimum
Design Criteria (MDC) for a wet pond. Please correct the following issues with the
proposed wet ponds (These comments are made assuming two distinct wet ponds, as
submitted. Some of these comments may not be applicable when the wet ponds are
combined):
a. General:
i. Do not use an estimated percent impervious in the wet pond calculations.
The actual percent impervious cover within the proposed drainage area
should be used.
ii. Please provide erosion protection calculations for STM A-0 and the curb
cuts to wet pond 1 (General MDC 4).
iii. Please include the maintenance access and easement for the wet ponds
(General MDC 8 & 9).
iv. The drawdown calculations appear to be calculated incorrectly (Wet Pond
MDC 7). The ponding height used in the calculations does not match the
WQv elevation as shown on the plans and the WQv elevation as shown on
the plans does not correspond to the elevation that the design volume
would fill the wet pond up to. Please refer to the Manual, Part B for
drawdown calculation information.

b. Wet Pond 1:
i. The average main pool depth is less than 3 feet (Wet Pond MDC 2). When
performing these calculations, the sediment storage area is not factored
into the volume of the main pool. The maximum depth of the main pool is
2 feet (659 ft — 657 ft) and the average depth is less than that. Please revise
the design so that the average depth is between 3 ft and 8 ft.
ii. Runoff from STM A-1 and the curb cut that does not flow into the forebay
both short circuit the wet pond (Wet Pond MDC 4). Please revise the
design to avoid this.
iii. The forebay volume is larger than 20% of the main pool volume (Wet
Pond MDC 5a). Don't forget to exclude the sediment storage area of the
main pool and forebay for this calculation.
c. Wet Pond 2:
i. The average main pool depth is less than 3 feet (Wet Pond MDC 2). See
above.
ii. Runoff from the forebay to STM B-EP short circuits the wet pond (Wet
Pond MDC 4). Please revise the design to avoid this.
iii. The forebay volume is smaller than 20% of the main pool volume (Wet
Pond MDC 5a).
10. There are noted discrepancies between the Supplement-EZ Form, Application,
calculations and plans. This list is illustrative as to the nature of the discrepancies and not
a complete list of noted errors and omissions. Please QA/QC the entire submission for
consistency prior to the next submittal:
a. The drainage area for wet pond 1 is shown in the Supplement-EZ as 272,768 sf (_
6.26 ac.) and 5.25 ac. in the Application and calculations.
b. The percent impervious area for the drainage area to wet pond 1 is shown as 63%
in the Supplement-EZ Form, 70% in the Application, and 80% in the calculations.
c. The sediment storage depth is shown on the Supplement-EZ Form as 6 in. and
shown as 1 ft. on the plans.
d. The impervious area breakdown for the wet ponds in the Supplement-EZ Form
does not match the breakdown in the Application.
e. The drawdown orifice for wet pond 1 is shown as 2 in. on the plans and 1.5 in. in
the Supplement-EZ Form.
f. Etc...
11. 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 February 20, 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 SW3191204 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: Mooresville Regional Office