SWA000075_Comment Response to July 10,2023 Letter_20240820

IMMI
Engineers,Surveyors,Planners,Scientists
July 10, 2024
Mr. Jim Farkas
State Stormwater Engineer
North Carolina Department of Environmental Quality
217 West Jones Street
Raleigh, North Carolina 27603
Subject: SWA000075 Atlantic & Southern Equipment—Transfer (Cabarrus)
Comment Response Letter
Dear Mr. Farkas,
We have considered and provided responses to the comments from the North Carolina Department of
Environmental Quality's review of the as-built submission for SWA000075 Atlantic & Southern Equipment,
dated May 29, 2024.
Comment Responses
I. "Permittee Certification:
a. Easements 1 — A recorded drainage easement for the SCM is required (per 15A NCAC
02H .1044(3)(j))." It is noted that the easement was recorded and uploaded (but not
provided as a hard copy) on April 5, 2024, however a revised permittee certification
indicating that an easement had been recorded was not provided.
b. Operation and Maintenance Agreement 2 —The O&M Agreement must be recorded with
the County Register of Deed (per 15A NCAC 02H .1044(3)(j))." See prior comment.
Response: The as-built permittee certification has been updated to reflect that the easement and
operation and maintenance agreement have been recorded.
2. "Designer Certification, General MDC:
a. Side Slopes 3 — For this item to be "As-Built Y", calculations showing that the steep slopes
are stable are required (per 15A NCAC 02H .1050(3)). NOTE: Per the requirements of the
Fast-Track Program,the project must be compliant with the rules/requirements upon project
completion (per 15A NCAC 02H .1043(1))." The supporting documentation indicating that
the soil and vegetation on the steep slopes will remain stable was not provided.As currently
shown, the design is not compliant with the rules/requirements and will either not be
approved or approved with conditions during the Final Fast-Track Permit review. If Mr.
Evans understands and accepts this risk,we can process the transfer(he will need to send us
something indicating this). If he does not accept this risk, we will be unable to transfer the
permit until this issue is addressed by the current permittee.
Response: Slopes that were built steeper than 3:1 are located primarily on the east and south
sides of the basin —where only local basin drainage will occur. Slopes have been in place since
2021 with no reports of erosion or bank instabilities.
5500 New Albany Road,Columbus,OH 43054•Phone [phone]• Fax [phone]
emhl.com

SWA000075 Atlantic& Southern Equipment July 10, 2024
Comment Response Letter
I, Steve Evans, understand and accept the risk that if erosion occurs on these steeper slopes that
maintenance will be completed to replant and stabilize the slopes.
Steve Evans, President,Atlantic & Southern Equipment
3. "Designer Certification,Sand Filter:
a. Two-chamber System 2—NOTE: Per the requirements of the Fast-Track Program,the project
must be compliant with the rules/requirements upon project completion (per 15A NCAC
02H .1043(1))." This minimum design criteria applies to all sand filters, whether they are
natural or manufactured. Guidance in our manual does allow for the sediment chamber to
be oversized (so long as at least half of the minimum required treatment volume is provided
in each chamber), but an undersized sediment chamber is not compliant with the
rules/requirements and will either not be approved or approved with conditions during the
Final Fast-Track Permit review.If Mr.Evans understands and accepts this risk,we can process
the transfer (he will need to send us something indicating this). If he does not accept this risk,
we will be unable to transfer the permit until this issue is addressed by the current permittee.
Response: Due to site constraints and layout of the basin,equivalent volumes between the sediment
area and remainder of the basin were not feasible.The minimum sedimentation basin surface area
equation As (ft2) = 0.066WQV (W) from the July 2007 NCDENR Stormwater BMP Manual was
used to ensure that enough area was provided within the sediment basin. Per the equation, the
sediment basin would require an area of 1,288 ft2. The Atlantic & Southern Equipment basin is
providing 6,1115 ft2 within the sediment basin portion of the sand filter,which exceeds the minimum
sizing guidance. j
I, Steve Evans, understand and accept the risk that the sediment chamber is not equivalent in size
to the remainder of the basin. Maintenance will be performed to ensure the sediment chamber is
performing as the design intends and is providing pretreatment to the sand filter.
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Steve Evans, President,Atlantic& Southern Equipment
Should you or your staff have any additional questions during your review of this letter, please contact me
at [phone].
Sincerely,
Brian Rossi, PE
Project Manager, Industrial & Logistics
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