NCC230402_ESC Approval Submitted_20230214

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
DOUGLAS R. ANSEL
Interim Director
NORTH CAROLINA
Environmental Quality
January 31, 2023
LETTER OF APPROVAL WITH MODIFICATIONS
SUM Storage, LLC
ATTN: Mr. John Anthony
518 E Fleming Dr
Morganton, NC 28655
RE: Project Name: SUM Storage
Acres Approved: 5.0
Project ID: BURKE-2023-030
County: Burke
City: Morganton
Address: 131 Stonebridge Dr.
River Basin: Catawba
Stream Classification: WS-IV
Submitted By: Clayton Engineering & Design - Mr. William S. Clayton, P.E.
Date Received by LQS: January 6, 2023
Plan Type. Commercial
Dear Mr. Anthony,
This office has reviewed the subject erosion and sedimentation control plan. We find the
plan to be acceptable with modifications and hereby issue this letter of Approval with
Modifications. The Modifications Required for Approval are listed on the attached page. This
plan approval shall expire three (3) years following the date of approval, if no land -
disturbing activity has been undertaken, as is required by Title 15A NCAC 413.0129.
As of April 1, 2019, all new construction activities are required to complete and submit an
electronic Notice of Intent (eNOI) form requesting a Certificate of Coverage (COC) under the
NCGO10000 Construction General Permit. After the form is reviewed and found to be
complete, you will receive a link with payment instructions for the $100 annual permit
fee. After the fee is processed, you will receive the COC via email. As the Financially
Responsible Party shown on the FRO form submitted for this project, you MUST obtain the
COC prior to commencement of any land disturbing activity. The eNOI form maybe accessed
at,deq.nc.gov/NCG01. Please direct questions about the eNOI form to the Stormwater
North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
Moan, cwouw, Asheville Regional Office 1 2090 U.S. Highway 70 1 Swannanoa, North Carolina 28778
°�a°"°°1p1Erv1onn0 m °°°� 828.296.4500

Letter of Approval with Modifications
SUM Storage, LLC
ATTN: Mr. John Anthony
January 31, 2023
Page 3 of 6
Enclosures: Certificate of Approval
NPDES NCG01 Fact Sheet
ec: Mr. William S. Clayton, P.E. [e-mail]
Regional Office file
MODIFICATIONS
Project Name: SUM Storage
Project ID: BURKE-2023-030
County: Burke
For final plan approval, please provide the requested information below.
1. Please provide on the plans a copy of the operation and maintenance of the
proposed post construction BMP. 115A NCAC 02H 1000}.
2. Because this site is in an MS4, Phase II area, please provide verification that
the MS4 Administrator has been contacted regarding this site. {15A NCAC 02H
1000}.
3. Please direct the discharge of the southern temporary diversion berm (TBD)
to the head of the skimmer basin. The berm is shown on the plan CCN 101 discharging
into the final settling chamber of the basin. {G.S. 113A-57 (3)}.
4. In accordance with Note 6 of the Sequence of Construction Activities, please
show the soil stockpile locations on plans. Locate the earthen -material stockpile
areas at least 50 feet away from storm drain inlets, sediment basins, perimeter
sediment controls and surface waters unless it can be shown no other alternatives

Letter of Approval with Modifications
SUM Storage, LLC
ATTN: Mr. John Anthony
January 31, 2023
Page 5 of 6
10. Please note that Hydrograph Report No. 2 using the SCS 10-year , 24-hour
storm duration shows the predeveloped runoff value to the proposed pond as 16.87
cfs. The peak flow of the 10-year storm runoff value used to size the temporary
sediment basin shows the runoff value as 9 cfs. The value used to size the temporary
sediment basin appears too small. Please review or revise these values and if
necessary adjust the size of the temporary sediment basin. {G.S. 113A-57 (3)}.
11. The online NOAA ATLAS 14 Point Precipitation Frequency Estimate for the 10-
year, 24-hour precipitation depth average is reported as 5.48 inches with a range of
5.09 - 5.89 inches. The value used to compute the pond size using the 10-year storm
was 4.80 inches, as shown in the calculations package. Erosion and sediment control
measures should be sized for the 10-year storm. Please review. {15A NCAC 04B
.01071.
12. Please show on the plans a stabilized outlet, or rip rap energy dissipater at the
discharge of the permanent drainage ditch. Please provide on the plans a
construction detail with dimensions. {G.S. 113A-57 (3)}.
13. Please provide construction detail with dimensions to the rip rap dissipater
on the west end of the bioretention cell forebay. {G.S.113A-57 (3)1.
14. Please provide a copy of the design calculations for the proposed bio-retention
pond. 115A NCAC 02H 10001.
15. Please add to the Sequence of Construction Activities on plan sheet CCN502
the following notes;
a) To file online an Electronic Notice of Intent (e-NOI) to obtain coverage under
the NPDES General Stormwater Permit,
b) To notify the NCDEQ Land Quality Specialist at least 48 hours before the
project starts,

Letter of Approval with Modifications
SUM Storage, LLC
ATTN: Mr. John Anthony
January 31, 2023
Page 6 of 6
c) That no major grading activities or basin construction are to take place during
wet weather or periods of predicted wet weather,
d) That prior to construction of the sediment basin, silt fence shall be installed
below the toe of the proposed embankment of the sediment basin to prevent
sedimentation damage during sediment trap construction,
e) The Sediment basin and bio-retention cell shall be provided with adequate
groundcover immediately upon construction,
f) That the site must be "storm ready" before any extended breaks in
construction activities including weekends,
g) That after receiving a close out inspection report from the NCDEQ Land
Quality Specialist, to file online an electronic Notice of Termination (e-NOT) to
end coverage under the NPDES General Stormwater Permit. {NCG01000}.
Ref: G.S. 113A-54.1 through G.S. 113A-57
Sections 15A NCAC 04A.0101 through 15A NCAC 04E.0504
General Permit NCG 010000 NPDES for Construction Activities

Letter of Approval with Modifications
SUM Storage, LLC
ATTN: Mr. John Anthony
January 31, 2023
Page 4 of 6
are reasonably available. Additionally, add a note to the plans to protect the stockpile
with silt fence installed along toe of slope with a minimum offset of five feet from the
toe of stockpile. Consider providing a stable stone access point if feasible. {G.S.113A-
57 (3)}.
S. To protect the entire embankment, please consider extending the rip rap of
the emergency spillway down the length of the embankment to its toe.{G.S. 113A-57
(3)}.
6. Please provide a construction a detail and method of stabilization of the
permanent drainage ditch to be installed as shown on plan sheets CGN101 and
CCN102. {G.S. 113A-57 (3)1.
7. To prevent the proposed bioretention structure from being contaminated with
sediment, please reword Temporary Skimmer Basin Notes, Note 3 shown on plan
sheet CCN101 to direct the construction crew not to convert Temporary Skimmer
Basin 1(TSB#1) to the Bioretention Structure until the site is permanently stabilized.
{G.S.113A-57 (3)}.
8. It appears that the southern temporary diversion ditch is to remain as a
permanent drainage ditch as shown on plan sheet CCN102 and CGN101. While there
is a construction detail for the temporary diversion ditch (Detail 5 on plan sheet
CCN502), there is not a construction detail for the permanent drainage ditches.
Please review. {G.S. 113A-57 (3)1.
9. Because this site is located in the City of Morganton, please review or revise
Note 2 on plan sheet CGN502 directing that the City of Charlotte Staff inspect the bio
retention cell during construction. {G.S.113A-57 (3)1.

Letter of Approval with Modifications
SUM Storage, LLC
ATTN: Mr. John Anthony
January 31, 2023
Page 2 of 6
Program staff in the Raleigh central office. If the owner/operator of this project changes in
the future, the new responsible party must obtain a new COC.
Title 1SA NCAC 413.0118(a) and the NCG01 permit require that the following documentation
be kept on file at the job site:
1. The approved E&SC plan as well as any approved deviation.
2. The NCG01 permit and the COC, once it is received.
3. Records of inspections made during the previous 12 months.
Also, this letter gives the notice required by G.S. 113A-61.1(a) of our right of periodic
inspection to ensure compliance with the approved plan.
North Carolina's Sedimentation Pollution Control Program is performance -oriented,
requiring protection of existing natural resources and adjoining properties. If, following the
commencement of this project, it is determined that the erosion and sedimentation control
plan is inadequate to meet the requirements of the Sedimentation Pollution Control Act of
1973 (North Carolina General Statute 113A-51 through 66), this office may require revisions
to the plan and implementation of the revisions to ensure compliance with the Act.
Acceptance and approval of this plan is conditioned upon your compliance with Federal and
State water quality laws, regulations, and rules. In addition, local city or county ordinances
or rules may also apply to this land -disturbing activity. This approval does not supersede
any other permit or approval.
Please note that this approval is based in part on the accuracy of the information provided
in the Financial Responsibility Form, which you provided. This permit allows for a land -
disturbance, as called for on the application plan, not to exceed the approved
acres. Exceeding the acreage will be a violation of this permit and would require a revised
plan and additional application fee. You are requested to file an amended form if there is any
change in the information included on the form. In addition, it would be helpful if you notify
this office of the proposed starting date for this project.
Your cooperation is appreciated.
Sincerel
. r
Mic ael Smith
Assist nt Regional Engineer
Land Quality Section