SW5210603_Response To Comments_20210817

RENGINEERING
Designing the Future... Today!
Wednesday July 28th, 2021
Jim Farkas
Environmental Engineer
NCDEQ Stormwater Program
512 N. Salisbury Street, Office 640 K
Raleigh, NC 27604
RE: Request for additional information Stormwater permit No. SW5210603
Duck Thru at Spring Hope, NC
Nash County
This letter is written in response to the comments and recommendations from officials from
Jim Farkas dated July, 21s' 2021. A reply or explanation for each comment issued by your
office is provided below and follows the original format of your memorandum.

NCDEQ Stormwater Program
Jim Farkas Jim. Farkas(a-)_ncdenr.go\� [phone]
There appears to be an overlap between the project area of this project and the
project area of SW5200701 (Bojangles at Spring Hope). Depending on the extent
of the overlap, permit SW5200701 may require a minor modification or a major
modification. Please clarify the extent to which permit SW5200701 will be
impacted. The modification process for permit SW5200701 must be initiated prior
to this permit (SW5210603) being issued.
There is an overlap between the area of SW5200701 and the proposed Duck
Thru. Permit SW 5200701 treats impervious areas on Lots 1, 2 and 3. This
project includes all of lot 1 on that permit as well as an additional 3.1 Acres
of new property. The SW5200701 permit allowed lot 1 to have 1.33 Acres of
impervious area. This project is designed to contribute 0.41 Acres of
impervious of the 1.33 Acres allowed. The proposed design takes the
remaining impervious area from the Duck Thru to a new facility. Therefore,
there is 1.33 - 0.41 = 0.92 Acres of impervious that was allowed under
SW5200701 that has not been used by the development of Lot 1 (Duck
Thru). The pond is constructed as originally designed so the owner would
like to reserve the 0.92 Acres of remaining treatment for future use of the
outparcels. Let us know the best way to proceed with SW5200701 based on
how Lot 1 (Duck Thru) has been designed.
Please see the stormwater narrative and a project area map for SW5200701
allocating impervious area from the Duck Thru project area. The Duck Thru
is in Area 1 on the project area map for SW5200701. The second map,
"IMPACT ON SW5200701 PERMIT AREA" shows the breakdown of the
impervious areas in and around the proposed Duck Thru that will overlap
with the SW5200701 permit.
2. When uploading the electronic files, please ensure that each document is
uploaded under its respective file type. Additional file types can be added to the
form by clicking on the "Add Another Post -Construction File Upload" link
immediately following the file upload section of the form. For example, the way
the files for this submission were uploaded resulted in each file being called
"Plansheet — Misc. Detail" despite the fact that some of these sheets were
grading sheets, cover sheets, etc...
Noted. In the future we will ensure the files are uploaded properly.

3. Please make sure that all of the submittal items are electronically uploaded (it
appears as though only the plansheets were uploaded). Submittal items, such as
the Application, supplement forms, calculations, and other supporting
documents, were not provided electronically. Please ensure that these items get
electronically submitted in the next submittal.
Done. All documents needed for the original submission and re -submittal
will be submitted online.
4. Please provide a pending sales agreement between the Property Owner and the
Applicant (Section 111, 1 c).
NOTE: Permit SW5200701 requires the Property Owner (of that permit) to
submit a permit modification to the Division prior to the sale or subdivision of the
permitted property.
The sales agreement has been provided.
5. Per 15A NCAC 02H .1003(3)(b), any off -site areas that drain to the proposed
SCM must be accounted for at their full build -out potential. This can either be
handled by having the Applicant and the Off -site Property Owner enter into a
legal agreement limiting the amount of BUA that can be built on this off -site area
(there's more information on this following the comments) or by assuming that
the off -site area is at its maximum build -out potential (typically 100% BUA). For
this reason, it is recommended to bypass all off -site areas around the proposed
SCM.
The drainage areas that used to collect run-off from offsite areas with
proposed development now by-pass the pond. The only offsite drainage
that reaches the pond is from the NC 581 ROW which does not have any
future proposed development.
6. Please dimension the project boundary in the main set of plans (Section VI, 8i).
Plan Sheet CE-01 appears to have some of the property boundary labeled in this
manner, however, the entire property boundary is required to be dimensioned.
The project boundaries are now dimensioned. Please see CE-01.
7. Please delineate the on -site wetlands in the main set of plans or place a note on
the plans indicating that there are no on -site wetlands (Section VI, 8m). Please
also indicate the individual that made this determination.
Terracon delineated the wetlands for this site in 2020 for the Bojangles
project. Their findings are included in this submittal. The wetlands are
located to the north and they are not located on the Duck Thru property.
Please see CE-01.

8. Please provide a second copy of the provided pre/post development runoff maps
so that I can add these to the main set of plans (Section VI, 8n & o).
A copy of the Pre and Post Development maps are now included in the plan
set. Please see CE-07 and CE-08. Please note that the offsite run-off
coming from the proposed development area to the west now by-passes
the pond. Therefore, the drainage areas are different from previous
submissions.
9. Since there are off -site components to the proposed SCM drainage area, please
explain how the off -site impervious area was determined (Section IV, 11).
The only off -site drainage to the SCM is from the NC 581 ROW and does not
possess impervious area. Any previously determined impervious area
coming from offsite sources was removed with the addition of the by-
passes of the pond.
10. Please provide a property deed for this property (Section VI, 10).
The property deed is included in this response.
11. Please provide official documentation showing that the Property Owner, It's Farm
Time, LLC, is in good standing with the Secretary of State and that the Signing
Official, Chester H. Brantley, has the authority to sign on their behalf.
We have included an Annual report of It's Farm Time from 2021 filed with
the North Carolina Secretary of State. Brad Mercer has the authority to sign
for It's Farm Time. Please see the Certification of Delegation of Authority
attached. Chester Brantley signs for Brantley et. al.
12. The drainage area used in the calculations (4.7 ac.) does not match the drainage
area information in the Application/Supplement-EZ Form (4.26 ac.), both of which
are different than the information shown on the post -development runoff map
(4.62 ac.). Please revise as needed for consistency. The remaining comments
will be made assuming that the drainage area to the proposed SCM is 4.26 ac
(since it was shown in multiple places).
The drainage area map has been updated to match the current grading plan
(notably the by-pass from offsite runoff). Now the drainage area to the pond
is 4.34 Acres. The impervious area/BUA did not change, it is still 3.6 Acres
.the resulting BUA=82.95%. The calculations, modeling, drawings and
forms have all been updated to be consistent with this new value. Please
note the post development drainage area is larger than the pre -
development area due to 0.13 Acres draining to the SCM from the NC 581
ROW.

13. Please do not include the sediment storage zone (portion of the main
pool/forebay that is above the excavated bottom and below the sediment storage
elevation) in the volume calculations of the forebay and main pool. Please also
clearly show the sediment storage elevation (in both the forebay and main pool)
on the wet pond cross-section.
Done, the change of removing the sediment storage values in the volume
calculations is complete. Please note that the new surface area values are
coming from a change requested in comment #16 of this letter. The
sediment storage in the forebay will be from 255-256. The sediment storage
in the main pond will be from 251-252.
14. The bottom elevation (255) and sediment removal elevation (256) shown in the
O&M Agreement Form appear to be incorrect. Please revise.
The O&M agreement form has been updated to reflect the accurate
conditions. The bottom is at 251 and the sediment removal elevation is 252
in the main pond.
15. Please show the maintenance access and easement on the main set of plans
(General MDCs 8 & 9). Please ensure that this easement extends to the public
right-of-way.
A maintenance and access easement is now shown on the plans. Please
see CE-02.
16. The main pool of the proposed wet pond appears to be too small (Wet Pond
MDC 1b).
NOTE: This assumes that the drainage area is 4.26 ac. which implies that the
%BUA is 84%, which changes the SA/DA ratio and results in the main pool being
too small (you should be able to fix this by using Equation 3 to calculate the
average depth of the main pool which should reduce the SA/DA ratio).
The drainage area map has been updated to match the current grading
plan. Now the drainage area to the pond is 4.34 Acres. The impervious
area/BUA did not change, it is still 3.6 Acres. The resulting BUA=82.95%.
The calculations, drawings and forms have all been updated to be
consistent with this new value.
With the Main Pond Surface area being too small to meet the surface area
requirement (again, changes due to the by-pass request). New grading is
proposed on the eastern side of the pond to meet the surface area
requirements. The pond Calcs and modeling results have been updated to
be consistent with the new grading. The plans sheets show the new
grading plan as well.

17. The incremental storage shown at elevation 262.0 on plan sheet CE-04 (10,015
cf) appears to be incorrect (the incremental storage shown might be the provided
storage between elevation 261.0 & 262.0 however, a cross-section for elevation
261.47 is included in the stage -storage table and should be accounted for).
You are correct the 10,015 CIF was the storage value between the 261.0 and
262.0 elevations. However, the grading of the pond has changed in
accordance with comment 16 of this letter. With this change, the WQV
elevation for the pond is now 261.4 and the subsequent incremental
storage is 4,177 CIF between 261.0 and 261.4. Please see CE-04 for this
change.
18. Since this project is located in a Nutrient Sensitive Watershed (NSW) please
provide something showing that this project uses an SCM that reduces nutrient
loading (as required per 15A NCAC 02H .1017(9)(c)). This requirement does not
mean that all of the NSW design requirements must be met.
We are designing a wet detention pond for the Duck Thru Site per the North
Carolina Stormwater Manual. The total Nitrogen removal rate for a Wet
detention pond is 25%, the total Phosphorous removal rate is 40%.
19. 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.
Done, the re -submittal package has been prepared in the format you
desired.
If there are any further questions, please contact Stocks Engineering at 252.459.8196.
Thanks!
Sincerely,
Stocks Engineering, P.A.
Isaac Hardison