SW4200501_Email for Impervious_20200602

Hannah Banks
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Hannah,
Farkas, Jim J <[e-mail]>
Thursday, May 14, 2020 3:16 PM
Hannah Banks
Renee C. Pfeifer
RE: [External] RE: SW4191201 - Lewisville Middle School
Follow up
Completed
Some of the comments that I made in the project return email were minor things that could have been resolved over
email, however the fact that there were multiple repeat comments led me to return the project as incomplete. As for
the new comments, comments can arise at any point in the review process. We try out best to issue every comment in
the earliest stage of the review as possible, but we are human and do occasionally make mistakes or overlook errors
only to find them later. In situations like this (Such as the 6 ft wide 10:1 slope vegetated shelf) I would not return an
application solely for new comments received on the third review, however, as previously stated, there were multiple
repeat comments.
A resubmission of the post -construction stormwater permit application and associated paperwork will be required as we
do not keep the submittal materials from returned projects. In theory, the approval process should not take 3-months as
the issues with this project have already been identified and (hopefully) corrected. It's entirely possible that the
resubmitted project will be approvable or approvable with minor comments addressed via email on the first submission.
We do not issue conditional approvals or offer leniency with regard to placing BUA on a project site. Either a post -
construction stormwater permit or authorization to construct (Part of the Fast -Track process) are required before any
BUA (except construction entrances) is placed.
To answer the questions from your 5/13/2020 email:
1) The stormwater wetland can be oversized (either for peak attenuation, a factor of safety, etc...), but the SCM
needs to be sized and evaluated for compliance with the MDCs using the design volume. The two main concerns
I had in that comment were the drawdown (Stormwater Wetland MDC 10) and the zone allocations (Stormwater
Wetland MDCs 6-9). You just need to show that these MDCs are met using the design volume. It is possible that
the SCM can meet the MDCs without having to be re -graded, it just needs to be shown.
2) This comment about the wet pond was made for similar reasoning to the prior comment. The temporary pool
elevation and drawdown calculations need to be shown for the design volume in order to meet Wet Pond MDC
7.
3) Assuming the off -site portion of the drainage area is 100% impervious and sizing the SCM to take that into
consideration is acceptable. Put a note on the drainage area sheet of the Supplement-EZ Form and in the
narrative stating that this is being done.
I understand that you're in a bit of a pickle. I'll try to get the resubmission turned around quickly. Let me know if you
have any other questions.
Jim Farkas
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Energy, Mineral, & Land Resources — Stormwater Program

512 N. Salisbury Street
1612 Mail Service Center
Raleigh, NC 27699-1612
[phone]
[e-mail]
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Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
Based on the current guidance to minimize the spread of COVID-19, the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working remotely or
are on staggered shifts. To accommodate these staffing changes, all DEQ office locations are limiting public access to
appointments only. Please check with the appropriate staff before visiting our offices, as we may be able to handle your
requests by phone or email. We appreciate your patience as we continue to serve the public during this challenging
time.
From: Hannah Banks <[e-mail]>
Sent: Wednesday, May 13, 2020 7:44 PM
To: Farkas, Jim J <[e-mail]>
Cc: Renee C. Pfeifer <[e-mail]>
Subject: [External] RE: SW4191201 - Lewisville Middle School
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
[e-mail]
Jim,
Thank you again for you reviews and I hope you are staying healthy. I wanted to follow up on the project return status of
this project. From the comments you gave below, I believe these are more so application and calculation issues with a
couple minor construction related comments, either regarding plants or the fine grading of the forebays. I understand
that there are outstanding comments that are currently not following the MDCs, but I believe that they can be
addressed fairly easily and will not change the construction of the ponds or wetlands in any significant manner. I also
understand that there are some repeat comments, however, there appear to be some new comments as well that were
not presented in our previous reviews.
This site is in construction and has erosion control measures in place. My concern is that a 3-month stormwater review
cycle will significantly alter the construction schedule due to the violation of the impervious surfaces being installed
prior to permits being issued. Due to these comments not reflecting significant plan changes, is there any leniency that
can be had in moving forward with construction including impervious surface? Ultimately, I don't feel as though these
comments pose a huge threat to water treatment and pond functionality; additionally, both ponds were oversized as a
result of erosion control design requirements and will not be converted or fine graded into their final SCM designs until
the site is near completion with the site fully stabilized. My hope is that we can move forward with construction as
normal while we sort out these last few comments.

I'd greatly appreciate a phone call tomorrow at your earliest convenience to talk to through what our options are
moving forward and if there is any leniency you may hold in what is allowed on site while we work to get this permit
approved. You can reach me on my cell 336-358-7756 in which my company is continuing to work from home.
Have a good rest of your evening!
Thanks!
Hannah Banks, El
Civil Designer
CLH design, p.a.
Collaborative Landscape Architecture and Civil Engineering
400 Regency Forest Drive, Suite 120
Cary, NC 27518
919.319.6716, ext. 4024
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From: Farkas, Jim J <[e-mail]>
Sent: Monday, May 4, 2020 9:04 AM
To: Kenneth A. Loring <[e-mail]>
Cc: Hannah Banks <[e-mail]>; Eplin, Tamera <[e-mail]>
Subject: RE: SW4191201 - Lewisville Middle School
Good Morning,
The Division of Energy, Mineral and Land Resources received and accepted a State Stormwater Management Permit
Application for the subject project on December 4, 2019 and requested additional information on January 6, 2020 and
March 10, 2020. A review of the application indicates that comments originally issued on January 6, 2020 have still not
been addressed and the submittal is incomplete. Per the requirements of Title 15A NCAC 02H .1042(3)(a)(ii) of the
Stormwater Management Rules, this Office is hereby returning the subject application as incomplete. The $505.00
application fee has been forfeited and a new fee will need to be provided if you choose to resubmit this application in
the future.
The original signed letter is being mailed to Colon Moore at:
Winston-Salem / Forsyth County Board of Education
475 Corporate Square Drive
Winston-Salem, NC 27105
The following comments were not addressed:
- Original Comment 5 — No note was found on any of the provided plan sheets indicating the presence or absence
of existing, on -site wetlands. Section VI, 8m requires that either a wetland delineation or a note stating no
wetlands are present, in addition to the name and title of the individual that provided this determination, be
included within the plan set.
- Original Comment 7 — The provided stage -storage table for the stormwater wetland indicates that the wetland
will hold approximately 3,800 cf of water at elevation 813. The design volume for this facility is 2,822 cf. The
temporary ponding elevation should be based off of the actual elevation that the design volume will fill the
wetland up to (Stormwater Wetland MDC 1). Since most all of the sizing criteria for a stormwater wetland are

based on the temporary ponding depth (Stormwater Wetland MDC 3), it is important that this be accurately
calculated.
Original Comment 10, Wet Pond Sheet, Line 44 — Line 34 indicates that the forebay cleanout depth (distance
from the permanent pool elevation to the top of the sediment storage elevation) is 54 inches (This also coincides
with the forebay stage -storage table's starting at elevation 822). Line 44 (the distance from the permanent pool
elevation to the excavated bottom of the forebay near the exit) must be at least 6 inches greater than Line 34
(to be compliant with Wet Pond MDC 3) and Line 43 (the distance from the permanent pool elevation to the
excavated bottom of the forebay near the entrance) must be greater than Line 44 (to comply with Wet Pond
MDC 5b). Since the contours are not precise enough to show these half foot elevation differences, please either
clarify the note, provide spot elevations, or clearly show these elevations on the cross-section to ensure it gets
constructed correctly. For example, the plans show that the deepest point of the forebay is the forebay bottom,
at elevation 821.5. The note says that the exit should be 6 inches shallower than the entrance. Assuming that
the entrance is the deepest part of the forebay, the exit elevation would be 822 (821.5 + 0.5) which is the same
elevation as the forebay sediment storage top (Thus violating Wet Pond MDC 3). Clarification is needed.
Original Comment 10, Stormwater Wetland Sheet, Line 28—The provided note presents the same issues as
noted above. The bottom elevations for the forebay and deep pools (Lines 27-29) do not correspond with the
information shown on sheet C07.05. Please either clarify the note, provide spot elevations, or clearly show these
elevations on the cross-section to ensure it gets constructed correctly.
Prior Comment 6, Supplement-EZ, Stormwater Wetland, Line 52 —This value should be the actual number of
plants provided in the shallow water zone per 200 sf of shallow water zone (not just the minimum amount per
the MDC). The issue with the form has been noted.
Prior Comment 7 — The plant quantities on sheet C07.06 still do not add up properly. For example, the shallow
water plant list specifies five different types of plants, four of which are shown to have a quantity of 126 and the
remaining one is shown to have a quantity of 127. Adding these quantities up (126 + 126 + 126 + 126 + 127)
results in 631 total plants. The plan sheet indicates that there are 554 total plants provided for this zone (The
same is true for the shallow land plant list, but the error is not as large, there is only a discrepancy of 1 plant).
The following issues were also noted during review:
- Supplement-EZ Form
o Wet Pond Page
■ Lines 22, 24, 46 and/or 47 — Either the slope (10:1) or the height & width (1 ft & 6 ft) of the
vegetated slope is incorrect. Please either correct the slope (Line 47), bottom of shelf elevation
(Line 22), top of shelf elevation (Line 24), and/or shelf width (Line 46) so that all of this
information is consistent. Please apply these changes throughout the entire submission.
■ Line 25 — The elevation of the temporary pool should be based on the design volume (29,521 cf).
Based on the provided stage -storage table, this volume would be stored below elevation 827.5.
Please ensure that this value and the drawdown equation is recalculated for the temporary pool
volume/elevation associated with the design volume. Please apply these changes throughout
the entire submission as needed.
■ Line 37 —The orifice diameter, as shown in the calculations and in the plans (2.5 in) does not
match the reported value (3 in). Please revise for consistency.
o Stormwater Wetland Page
■ Lines 23 & 39 — These items contradict each other.
■ Lines 27-29 — These values do not correspond with the information shown on sheet C07.05.
■ Lines 24, 30, 35-40, & 48 — See earlier comment about the stormwater wetland temporary
ponding elevation.
■ Line 42 —The distance from the permanent pool elevation to the forebay entrance (30 in) does
not match the difference between Line 25 (812) and Line 27 (810) (812 — 810 = 24 in).
■ Line 43 —The distance from the permanent pool elevation to the forebay exit (24 in) does not
match the difference between Line 25 (812) and Line 28 (810.5) (812 — 810.5 = 18 in). NOTE: 18
in is less than the requisite 24 in (Per Stormwater Wetland MDC 6).

It is recommended that:
- Deep pool plantings not be planted in the deep pool nearest the outlet as they may cause clogging.
- FYI, since having issued my previous round of comments, I received clarification from within the Department
that all SCMs with off -site drainage need to have either the legal agreement in place between the property
owners limiting the amount of off -site BUA that will drain to the facility or be designed in accordance with 15A
NCAC 02H .1003(3)(b). The Department's preferred option is to have the legal agreement in place as it is the
best method for ensuring long-term compliance with the permit, but 15A NCAC 02H .1003(3)(b) is also
acceptable since it is statute. Diverting the off -site drainage around an SCM is still an option.
Please let me know if you have any further questions.
Jim Farkas
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Energy, Mineral, & Land Resources — Stormwater Program
512 N. Salisbury Street
1612 Mail Service Center
Raleigh, NC 27699-1612
[phone]
Jim. Farkas @ ncdenr.
F�.y3TY. f'MSFk'{IEW
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
Based on the current guidance to minimize the spread of COVID-19, the Department of Environmental Quality has
adjusted operations to protect the health and safety of the staff and public. Many employees are working remotely or
are on staggered shifts. To accommodate these staffing changes, all DEQ office locations are limiting public access to
appointments only. Please check with the appropriate staff before visiting our offices, as we may be able to handle your
requests by phone or email. We appreciate your patience as we continue to serve the public during this challenging
time.
From: Farkas, Jim J
Sent: Tuesday, March 10, 2020 4:42 PM
To: [e-mail]
Cc: Hannah Banks <[e-mail]>; Eplin, Tamera <[e-mail]>
Subject: RE: SW4191201 - Lewisville Middle School
Good Afternoon,
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater Management Permit Application
for the subject project on February 3rd, 2020. A review of that information has determined that the application is not

complete. Attached is a letter describing the items that need to be submitted. If you have any questions, please feel free
to contact me. My contact information is listed below.
Thank you,
Jim Farkas
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Energy, Mineral, & Land Resources — Stormwater Program
512 N. Salisbury Street
1612 Mail Service Center
Raleigh, NC 27699-1612
[phone]
Jim -.Farkas @ ncdenr. gov
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-
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Farkas, Jim J
Sent: Monday, January 6, 2020 8:23 AM
To: [e-mail]
Cc: Wise, Brandon L <[e-mail]>
Subject: SW4191201 - Lewisville Middle School
Good Morning,
The Division of Energy, Mineral and Land Resources (DEMLR), received a Stormwater Management Permit Application
for the subject project on December 4t", 2019. A review of that information has determined that the application is not
complete. Attached is a letter describing the items that need to be submitted. If you have any questions, please feel free
to contact me. My contact information is listed below.
Thank you,
Jim Farkas
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Energy, Mineral, & Land Resources — Stormwater Program

512 N. Salisbury Street
1612 Mail Service Center
Raleigh, NC 27699-1612
[phone]
[e-mail]
e::!::—QI-03'
EAAOP
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.