SW3230601_Response To Comments_20231127

November 27, 2023
landscape architect
NCDEQ J.DAVIDLEDFORD, RLA
c/o Brianna Holland 2730 Maiden Highway
512 N. Salisbury Street, Office 640E Lincolnton, NO 28092
Raleigh, NC 27604 Cell 704-530-7880
RE: Denver Fitness Facility- SW3230601 j david fed [e-mail]
N. NO 16 Business
Denver, NO
Brianna,
This is a cover letter for the Request for Additional Information
that we received from your office. The requested information has
been addressed with revised forms, calculations, and plans. In the
following pages is the comment list for requested information along
with a response in red to the items addressed and the location to
find them as needed. I have also enclosed hard copies as requested
in the list for your use in the review of the project.
If you have any additional questions or comments during your
review, feel free to contact me at any time.
Thanks You,
David

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November 27, 2023 ,t,3
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NCDEQ
c/o Brianna Holland-� •,, ,,
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512 N. Salisbury Street, Office 540E landscape architect
Raleigh, NC27604 J,DAVIDLEDFORD, RLA
RE: Denver Fitness Facility 2730 Maiden Highway
Application Review Comments Lincolnton, NC 28092
N. NC 16 Business Cell 704-530--7880
Denver, NC [e-mail]
The Division of Energy, Mineral and Land Resources(DEMLR), received a Stormwater
Management Permit Application for the subject project on August 18, 2023. A review of that
information has determined that the application is not complete.The following information is
needed to continue the stormwater review:
1. Off-site Drainage Area:
a. Per 15A NCAC 02H .1003(3)(b) any off-site areas that drain to the SCM must be
accounted for at their full build-out potential.This can be accomplished by having the
property owners enter into a legal agreement limiting the amount of BUA and
drainage area directed from the off nsite property to the SCM or by assuming that the
off-site area is 100%BUA(Its full build-out potential). Bypassing off-site drainage
area around the SCM is recommended. If the off-site area is not bypassed, or a legal
agreement reached, please revise the calculations, Supplement-EZ, and Application
accounting for the offsite area as 100%BUA.
Off-site Drainage has been considered 100%BUA for the design of the Sand Filter Drainage
Area since the additional imperious area is small compared to the overall drainage area. Sand
Filter size has been adjusted accordingly_ See attached revised Application Project
Information Sheet, Supplement-EZ Drainage Areas&Sand Filter Sheets, Calculations; and
Plans.
2. On-site BUA
a. Per Sheet C5, "Drainage area includes additional on-site impervious area that will not
be able to reach sand filter to allow for additional treatment volume in SCM."
i. The drainage area means the entire area contributing surface runoff to a single
point 15A NCAC 02H .1002 (15).The drainage area delineated on the plans as
required per 15A NCAC 02H .1042 (2) (g) (iv) needs to accurately depict the
drainage area that will reach the sand filter.
All On-site BUA has been directed to the SCM Sand Filter for treatment with the addition of
storm drains(i.e. CS 46-A and Entrance Drive Trench Drain) along with re-grading as needed.
il. If directing the untreated BUA to an SCM is not practicable,you may permit the
portions of the project area that do not drain to the SCMs as low-density areas
(provided that this area meets the low-density requirements). If the bypassed area
does not meet the low-density requirements, a variance can be sought in
accordance with 15A NCAC 02H .1003(6). (NOTE: For a variance to be
approved, you must demonstrate that the variation provides equal or better
stormwater control and equal or better protection of waters of the State than what
the rules require). Please revise as needed.
Ail On-site BUA has been directed to the SCM Sand Filter,
3. Consistency
a. The Supplement-EZ, Sand Filter, Line 18 states that the SHV T elevation is 791.001,
but the Sand Filter Section View on Sheet D6 lists the elevation as 792.00". 15A
NCAC 02H A 056(1).
SHwT elevation has been revised on the Sand Filter Section View on Sheet D6 to 791.00'

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November 27, 2023
f r
NCDEQ
r '
c% Brianna Holland
512 N. Salisbury Street, Office 640E _ landscape architect
Raleigh, INC 27604 J.DAVIDLEDFORD, RLA
RE- Denver Fitness Facility 2730 Maiden Highway
Application Review Comments Lincolnton, NC 28092
N. NC 16 Business Cell 704-530-7880
Denver, NC [e-mail]
The Division of Energy, Mineral and Land Resources(DEMLR), received a Stormwater
Management Permit Application for the subject project on August 18, 2023. A review of that
information has determined that the application is not complete. The following information is
needed to continue the stormwater review:
4. Plans
2x signed&sealed hard copies of a plan sheets showing the following (This item is required
per15A NCAC 02H .1042(2)(g) and per Section VI, 8 of the Application):
Enclosed are 2x signed &sealed plan sheets.
a. Please show the bottom contour of the sediment chamber in plan view,
Sand Filter sediment chamber bottom contour has been shown in the plan view detail on
Sheet 06 per your comment clarification response.
b. The stage storage table shows contours 796.50', 797.50', 798.50', and 799.50', but
the contours shown on the plans are in foot increments. Please either show the half
contours on the plans or revise the table to show foot increments so that the areas
shown in the table can be measured in the plans to confirm accuracy. Confirm the
contour areas. Manually measuring the 799.50' contours shown on Sheet D6 gave a
value of approximately 1,763 SF for the sand chamber instead of 1,906 SF and
approximately 1,836 SF for the sediment chamber instead of 1,906 SF. Revise the
package as necessary if the contour areas and volumes need to be updated.
Stage Storage Table Contours have been revised to foot increments on Sheet D6 to match
plan contours based on your comment clarification response. Square Footage Areas&Cubic
Foot Volumes have been adjusted to match the increased Sand Filter Depth.
C. Per the Supplement-EZ, Sand Filter, Line 29, the elevation of top of weir between
chambers is 800 fmsl. Please show this elevation in the plan view as a contour or spot
elevation_
The 800 fmst elevation contour for the weir has been shown on all plan view sheets based on
the revised size of the Sand Fllter,
5. Supplement-EZ
2x hard copy of the complete, original Supplement-EZ Form is required per Sections V&Vi, 3
of the Application
Enclosed are 2x hard copies of the complete, original Supplement-EZ.
a. Sand Filter, Line 27-The physical depth of the sediment chamber is the distance
from the bottom of the sediment chamber(796.50')to the invert of the bypass device
(799.50').
Line 27 has been revised to shore;the physical depth of 42" based on revised Sand Filter.
b. Sand Filter, Line 28-The ponding depth in the sediment chamber is the distance
from the permanent pool surface elevation to the invert of the bypass device. Per Line
24, there is no permanent pool, therefore there is no ponding depth above the
permanent pool. Please revise.
Line 28 has been revised to N/A since there is no permanent ponding depth proposed-
C. Sand Filter, Line 33-The physical depth of the sand chamber Is the distance from
the bottom of the sand chamber(796.501)to the invert of the bypass device(799.50').
Line 33 has been revised to show the physical depth of 42"based on revised Sand Filter.

November 27, 2023
NCDEQ
c/o Brianna Holland
512 N. Salisbury Street, Office 640E landscape architect
Raleigh, NO27604 J.DAVIDLEDFORD, RLA
RE: Denver Fitness Facility 2730 Maiden Highway
Application Review Comments Uncointon, NC 28092
N. NO 16 Business Cell 704-530-7880
Denver, NC [e-mail]
The Division of Energy, Mineral and Land Resources(DE=MLR), received a Stormwater
Management Permit Application for the subject project on August 18, 2023. A review of that
information has determined that the application is not complete.The following information is
needed to continue the stormwater review:
6. Previous Comment: 3 d. "Provide engineering calculations exhibiting that
stormwater outlets are designed so that they do not cause erosion downslope of the discharge
paint during the peak flow from the 10-year storm event per 15A NCAC 02H .1003(5). Show
with the calculations that the flow rate of water does not exceed the maximum
permissible velocity for the condition and type of soil and groundcover over which the
water Is flowing_The proposed Swale and primary overflow system outlet to an existing
headwall and culvert. Please show the outlet of the existing system and demonstrate that
erosion Is not caused.
a. The response Indicated that dissipated volume was achieved prior to the headwall
with the installation of the riprap energy dissipators.This is acceptable for the flow
leaving the SCM. Please provide calculations exhibiting the stability of the Swale that
is directing flow to the receiving headwall. 15A NCAC 02H .1003 (5)
Per comment clarification response.; a Swale analysis has been calculated and enclosed based
on the overall Q10 at the point of the entrance to the existing headwall. Since the velocity is
close to the maximum permissible velocity of established tall fescue groundcover, a"Class B"
permanent rip rap liner has been proposed. See attached supporting velocity and shear stress
calculatlons for the rip rap lined ditchline.
b. There is a Swale south of the pickle bail courts. It is unclear where stormwater from
this Swale will discharge. Please show the outlet and demonstrate that erosion is not
caused downslope of the discharge point during the peak flow from the 10-year storm
event per 15A NCAC 02H .1003(5).
Per comment clarification response, the swale south of the eastern pickleball courts drains to
the relatively flat area to the east of the courts then flows across the parking lot to the northern
swale then to C.B. #9 and directed to the SCM Sand Fitter. An existing spot elevation has
been added to the plans near the 5/8"iron set to confirm a higher grade as requested. In
addition, a Swale analysis and ditchliner calculations are enclosed at the point of entrance to
C_6 #9 to show Swale stability.
"*** Sheets Si Site Plan &S2 Landscape Pian have been included in the revised sheets since
the proposed water and sewer utility locations have been revised per Lincoln County
Review Comments.