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ROY COOPER 5 =
Governor E7
ELIZABETH S.BISER
Secretary *Eaf QUAMNVEw x
BRIAN WRENN NORTH CAROLINA
Director Environmental Quality
November 10, 2022
Thomas &Hutton Engineering Co.
Attn: Matthew S. Kiker, PE
1020 Euclid Avenue
Charlotte, NC 28203
AND
KH Wesley Chapel, LLC
Attn: Mike McLendon, Authorized Signatory
8913 Silver Springs Court
Charlotte, NC 28215
Subject: Request for Additional Information
Stormwater Permit No. SW3220803
Cresswind Phase 4
Union County
Dear Mr. Kiker and Mr. McLendon:
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater
Management Permit Application for the subject project on August 15, 2022. 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 QA/QC the submission. There were a number of issues that prevented a complete
review of the project (I reviewed as much as I could based on what was provided, but
there may be other comments that come up when the submission is corrected). Some
notable examples are provided below:
a. Please clarify the BUA accounting for this project. Below is a summary of the
drainage area information for the proposed wet pond as shown in the Application
(Section IV, 10) and the Supplement-EZ Form (Drainage Areas Page)
Item Application Su lement-EZ Form
Building/Lots/Roof 715,000 sf 1,001,880 sf
Street/Roadway 217,681 sf 284,716 sf
Parking 143,000 sf 290,000 sf
Sidewalk 62,284 sf 84,156 sf
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 _
oepm nt of EnvimnmwUl uwl ry 919.707.9200
Future 0 sf 56,295 sf
Total BUA 1,137,965 sf 1,840,410 sf
%BUA 55% 40%
Please revise as needed so it is clear what the proposed BUA for this project is.
b. The calculations show 23.0 ac (1,001,880 sf) of BUA draining to the SCM while
the Application shows 1,137,965 sf and the Supplement-EZ Form shows
1,840,410 sf.
c. The provided cross-section details on plan sheet C3.29 do not appear to
correspond to the grading plans (for example, the cross-section shows the
permanent pool surface elevation at 567.0' while the other submittal items
indicate 574.5', the drawdown orifice is shown on the plans to be 3" and 4" in the
other submittal materials, etc...).
d. The number of lots associated with this project is shown as 143 in the narrative
and Application (Section IV, 10), however the plans show 144 (Lots 371 to 514
are part of this phase).
e. The plan view of the wet pond does not show the forebay.
2. Please provide calculations showing that the inlet and outlet protection is adequately
sized (General MDC 4).
3. Please exclude the sediment storage zone from the main pool and forebay volume
calculations (Wet Pond MDCs 1, 2, 3, & 5). I can't say for sure if this is an issue since
the provided cross-section view of the pond has the wrong elevations, but it appears to be
the case based on the other provided submittal items. Please revise as needed.
4. As designed, the forebay is too large (Wet Pond MDC 5a). Using the provided forebay
and main pool volumes from the stage-storage tables (see earlier comment, these values
will need to be revised to exclude the sediment storage zone however this issue still
appears to be present when this is taken into account) of 28,375 cf and 134,764 cf
respectively results in a forebay that is 21% the size of the main pool (28,375 cf/ 134,764
cf=21% >20%). Please revise as needed.
5. Please correct the following issues with the Supplement-EZ Form:
a. Cover Page:
i. Line 2—The Project Area value shown (107.1 ac) does not correspond to
the project area value shown in Section IV, 7 of the Application. Please
revise as needed.
b. Drainage Area Page:
i. It is strongly recommended to use the latest version of this form (available
on our website: https:Hdeg.nc.gov/about/divisions/energy-mineral-and-
land-resources/stormwater/stormwater-pro gram/stormwater-desi gn). It
contains some modifications from the version of the form that you used,
such as providing a line for the total drainage area to the SCM.
ii. Revise the values as needed in accordance with the earlier comment. The
entire site column should be an accounting of the entire site, not just a sum
of the other columns. If any portions of the project area are located outside
of the drainage area to the SCM they should be accounted for in this
column.
iii. Lines 17-19 —Please provide these items for the wet pond column.
c. Wet Pond Page:
i. Line 9—The provided detail did not appear to indicate a drawdown orifice
that could be used to dewater the entire pond. Please revise as needed.
ii. Line 26—Per the provided calculations, the surface area of the main pool
is 36,947 sf(39,712 sf is shown).
iii. Lines 27, 28, & 32—These items will need to be recalculated (to exclude
the sediment storage zone).
iv. Line 28 —Per the provided calculations, the average depth is 3.97 ft (4.78
ft is shown). Please revise as needed.
6. Please reupload the plan sheets from the last submission for this project individually
under the appropriate specific file types ("Plansheet—Cover Sheet", "Plansheet—
Grading/Drainage Plan", etc...). Laserfiche does not handle large files (such as an entire
plan set) well. NOTE: We do not require a full plan set (either electronic or hard copy)
you only need to provide the plan sheets needed for us to complete the review.
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:
https://edocs.deq.nc.gov/Forms/SW-Supplemental-Upload
b. Hard copies must be mailed or delivered to the following address:
i. For FedEx/UPS:
Jim Farkas
512 N. Salisbury Street, Office 640E
Raleigh, NC 27604
ii. For LISPS:
Jim Farkas
1612 Mail Service Center
Raleigh, NC 27699-1612
iii. 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 package 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.
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 December 10, 2022, 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 SW3220803 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
Jim.Farkas@ncdenr.gov or(919) 707-3646.
Sincerely,
Jim Farkas
Environmental Engineer
Stormwater Program
cc: Mooresville Regional Office