SW8040836_Historical File_20191003

Burd, Tina J
From: Burd, Tina J
Sent: Monday, September 30, 2019 9:57 AM
To: [e-mail]
Subject: SWB 040836 - Wilmington International Airport
The Wilmington Regional Office of the Division of Energy, Mineral and Land Resources (Stormwater Section) accepted
the Stormwater Permit Renewal Application and $505.00 fee for the subject project on September 25, 2019. The project
has been assigned to Garrett Zorda and you will be notified if additional information is needed.
Best Regards,
Tina Burd
Administrative Associate II
Wilmington Regional Office
Division of Environmental Assistance & Customer Service
Phone [phone]
NCDEQ
Wilmington Regional Office
127 Cardinal Drive Ext.
Wilmington, NC 28405
rf:.,rp tea anr:+;' .:.. ;+(YC1 .': is sir,"_�f;,'t to tt]e
...... ;;;:_ k tl ,rcI parties.

] j Application Completeness Review Checklist
Project Name: ( U i - — Date Delivered to W IRO: ,
i?l �Gw -�-I ec_c_, BIMS Received/Accepted Date: ` C
Project County/Location: *BIMS Acknowledged Date:
Rule(s): 1:12017 Coastal 1:32008 Coastal IE:11995 Coastal Phase II Universal ED1988 Coastal
Permit Action: New / Major Mod / Minor Mod 4 Renew / Transfer **New Permit #:
Permit Type HD OLD / LD Overall / HD &LD Combo Asting Permit #. G - � Of 3 l
General Permit / Offsite % ExemlaE / Rescission I IPE Cert on File?
SCM Type(s): �T Offsite to SW8:
Development Type: ommer ; / Residential / Other Master PE Cert on File?
Subdivided?: Subd'Lvhsion or Single Lot
For New or Transferred Permits Permittee is:
Property Owner(s) ElDeveloper IDLessee OFrurchaser 11 HOA
Paperwork
Emailed Engineer on:
FiSupplement(s) (1 original per BIVIP)
Wppli
wiith correct/ original signatures (1 original per BMA' except LSfVFS and swages!
cation with correct/original signatures
Corp or LLC: Sig. Auth. pef SoS or Signature Authorization letter or report
D$505 (within 5mo) Check#(s): (fl S 535 MNo Fee
Soils Report; w/'SHWT or General Report
Calculations (signed/sealed)
Deed Restrictions, if subdivided:
**Signed & Notarized Template
Correct _Tern plate (Comm/Res & HDILd) or Dec. Covenants
Covenants
Recorded Plats F-150%or more Lots Sold list
Project Narrative
EIUSGS Map
Plans
Strecsm Class:
EISA Map DORW Map
Email Address: Design Engineer
Email Address: Property Owner
Deed
Email Address: Lessee
Lease Agreement
Email Address: Purchaser
Purchase Agreement
Email Address: Developer
Email Address: HOA Representative
E-12 Sets Wetlands: Delineated or No Wetlands
Vicinity Map Project Boundaries
01-egand Layout ('proposed HUA diineiisions)
EIDA Maps F-10etails (roads, cul-de-sacs, curbs, sidewalks, BMFs., Buildings, etc)
Existing Conditions Landscape Plan
❑Grading MPE Seal
REVIEWER NAME:
NOTES TO REVIEWER: *Enter BIMS Acknowledged Date on this Sheet
"FOR NEW Projects -Enter New Permit # on
Supplements & Deed Restiction Templates.
ry\Pi ucedures%Cioectfliszs\Cunipleteriess Review Check is:_ 2018 03 13

T/ f'l LM
September 23, 2019
Airport .yt.thoriv. Georgette Scott
Environmental Program Supervisor II (Stormwater)
Donna Girardot NCDEQ
Chairman
127 Cardinal Drive Ext,
Thomas Wolfe Wilmington, NC 28405
Vice -Chairman
Harry W. Stovall Ref: State Stormwater Permit Renewal
Secretary Wilmington International Airport Mater Plan and EDDB
Permits SW8 040836 and SW8 050547
Carter T. Lambeth
Julia Olson-Boseman
Dear Ms. Scott,
F. Spruill Thompson
W. Lee Williams
Please find attached a permit renewal application for the projects listed above. The
package includes the following items:
• Permit Renewal Application and check for $505 WS O40836
• Permit Renewal Application and check for $505 for SW8 050547
Julie A. Wilsey, AAE • One USB.drive containing:
o Electronic copy of applications for both SW8 040836 and SW8 050547
0 0&M Agreement for SW8 050547
Other items, including recorded documents required by the original permit, designers
certifications and documentation of BUA allocated to date for both permits have
previously been submitted to the Regional Office and have not required modification
since the most recent submittal.
If you have any questions regarding these applications or need any additional
information, please do not hesitate to contact me.
Respectfully,
Granseur Dick, PE
Wilmington Planning & Development Director
International Airport Cc: Eric Stumph, PE, Talbert & Bright (By Email)
1740 Airport Blvd., Ste. 12
Wilmington, NC 28405
910.341.4333

ROY COOPER
Governor
MICHAEL S. RE-GAN
Secretary
Coasta[Mana9ement _ _ _ BRAXTON DAVIS
ENVIRONMENTAL DUALITY
— -- -- - . -
Director
May 25, 2018 c7
FROM: Heather Coats, Assistant Major Permits Coordinator
NCDEQ - Division of Coastal Management
127 Cardinal Drive Ext., Wilm., NC 28405 heather. coats aQncdenr gov
Fax: [phone] (Courier 04-16-33)
SUBJECT: CAMA Application Review
Applicant: Wilmington Airport Authority
Project Location: 1740 Airport Blvd., adjacent to Smith Creek, in Wilmington,
New Hanover County
Proposed Project: to mitigate hazards to wildlife by making upgrades to an existing stormwater
system and by the construction of a riprap outfall area
Please indicate below your agency's position or viewpoint on the proposed project and
return this form to Heather Coats at the address above by June 20, 2018. If you have any
questions regarding the proposed project, contact Brooks Surgan at [phone] when appropriate
in-depth comments with supporting data is requested.
REPLY: This agency has no objection to the project as proposed.
"Additional comments may be attached"*
This agency has no comment on the proposed project.
This agency approves of the project only. if the recommended changes
are incorporated. See attached. Th:s
-Red,-D cam "Tr
T rom0.l -,A ��- 6+0rwX,.0du
Thlis agency objects to the project for reasons described in the attached
comments.
R
SIGNED DATED �V1 10ZO (�
v i
State of North Carolina I Environmental Quality I Coastal Management
127 Cardina! ;hive Ext., -Wilmington, NC 28405
910-796-7215

04033�
TALBERT & BRIGHT, INC. �r>d114
ENGINEERING & PLANNING CONSULTANTS
LETTER OF TRANSMITTAL
To: N.C. Division of Environmental Quality
Land Quality Section
127 Cardinal Drive Ext
Wilmington, NC 28405
Date: 8/5/18 Pro'. No. 3301-1504
Attention: Ms. Linda Lewis
Re: Wilmington International Airport
Wildlife Hazard Mitigation Project for
Wet Detention Basins and Open Ditches — Phase 2
Stormwater Management
WE ARE SENDING YOU:
® Attached
❑ Under Separate Cover via
❑ Shop Drawings
❑ Prints
❑ Plans
❑ Copy of Letter
❑ Change Order
❑ Other
the following items:
❑ Specifications
ITEM
DATE
NO.
DESCRIPTION
1
Project Narrative and Exhibits
RECEIVED/NCDENR/DWR
8
Waiter 0112lity Regi
pal
Operations Section
Wil '
THESE ARE TRANSMITTED, as checked below:
❑
For Approval
❑
®
For your Use
❑
®
For Review and Comment
❑
❑
As Requested
❑
❑
FOR BIDS DUE ON
REMARKS
No Exception taken
Make Corrections Noted
Amend and Resubmit
Rejected — See Remarks
❑ Resubmit Copies for Approval
❑ Submit Copies for Distribution
❑ Return Corrected Prints
❑ Prints Returned After Loan to Us
❑ Other
An Erosion & Sediment Control Plan has been submitted for review for this project.
COPY TO
SIGNED Robert Williams, P
ENGINF_.ER.TNG & PLANNING CONSULTANTS
4810 Shelley Drive Wilmington, NC 28405 910.763.5350 FAX [phone]

WILMINGTON INTERNATIONAL AIRPORT
WILMINGTON, NC
WILDLIFE HAZARD MITIGATION PROJECT — PHASE II
TBI Project No. 3301-1604
STORMWATER MANAGMENT
PROJECT DESCRIPTION
The Wilmington International Airport (ILM) has undertaken a systematic multi -year effort to
mitigate wildlife hazards and attractants at the Airport. The goal for this project is to modify two
existing drainage ditches/channels that consistently hold water to reduce or eliminate their
potential to attract wildlife which can be hazardous to aircraft using the Airport. One of the open
ditches/channels is located on the west side of the approach end of Runway 35 and south of
Taxiway A and is referred to as Ditch/Stream 1 on the project plans. The second open
ditch/channel is located within the infield area of Runway 24, Taxiway G, and Taxiway `B', and
is referred to as Ditch/Stream 3 on the project plans. Currently, both locations hold water on a
consistent basis creating a wildlife attractant that can be detrimental to airport operations.
Locations can be seen on attached Figure 1— Overall Plan.
Ditch/Stream if is a drainage channel located near the approach end ,of Runway 35 and outlets
into Smith Creek on the southside of the Airport. The stormwater pipe system that outlets into
the ditch runs underneath Taxiway A. A second channel connects to Ditch/Stream 1 from the
west. This channel begins at a pipe outfall that runs underneath an abandoned taxiway. These
drainage channels constantly hold water which creates a wildlife attractant. Birds and other
animals (which can access the channel through the existing fence/ditch crossing) have been
observed in this channel which is within 600' of the end of Runway 35. In October 2017, a
passenger plane struck a coyote on the airfield; it is possible that the coyote entered the airfield
from the existing fence crossing over this ditch. This project will extend the existing pipe outlets
from the two existing pipe systems and combine them into a single pipe system to carry
stormwater to the airport perimeter fence line and will eliminate standing/open surface water in
this area and will eliminate the fence/ditch crossing which currently enables animals to enter the
airfield perimeter at this location. It is proposed that 415 linear feet of pipe be constructed to
extend the two pipe outlets to the perimeter fence. The channels also display areas of severe
erosion which is causing sediment to be transported downstream. The erosion is a maintenance
problem for the Airport and reduces water quality.
Ditch/Stream 3 is a drainage channel that is partially lined with concrete located between triple
60"-72" culverts that run under Taxiway `B' and triple 60" culverts that run under Runway 6-24.
The drainage channel ultimately drains to Smith Creek. This open channel between the two sets
of culverts constantly holds water. This project will extend the existing pipe system
approximately 196 feet to connect the existing culverts and will eliminate standing/open surface
water in this area next to Runway 6 24.
Page 1 of 5

Ditch/Stream I — Looking Upstream to Existing Pipe Outlet
Ditch/Stream I Looking Downstream to Fence Crossing
Page 2 of 5

"Ot
�Q 2`/,2 T/ 2 C

Ditch/Stream 3 - Looking Upstream to Triple Culverts under Taxiway B
LAND DISTURBANCE AND IMPACTS
Ditch/Stream 1 includes 0.07 acres of existing jurisdictional wetlands, 262 linear feet of existing
404 jurisdictional stream, and 30 linear feet of existing navigable waters. The wetlands are in the
drainage swale from the pipe outfall under the abandoned taxiway. The 404 jurisdictional stream
is the channel from the pipe outlet from under Taxiway A to the airport perimeter fence line. The
30 linear feet of navigable waters is outside the Airport perimeter fence within an existing
CAMA Area of Environmental Concern (AEC). Ditch 3 includes 196 linear feet of existing 404
jurisdictional stream.
The impacts to the navigable waters, 404 streams, and wetlands are being permitted through a
NC Division of Coastal Management CAMA major development permit, US Army Corps of
Engineers 404 General Permit 291, and NC Division of Water Resources 401 Water Quality
Certification. The permit application has been submitted to the Division of Coastal Management.
Maps of the proposed impacts to Ditch/Stream 1 and Ditch/Stream 3 are shown on attached
Figures 2 through 5. These impact maps were included with the CAMA major development
permit application.
The Airport is pursuing a CAMA major development permit based on field visits and
correspondence between The Airport, Talbert & Bright (Consulting Engineer), WithersRavenel
(Environmental Consultant), NC Coastal Management, The US Army Corps of Engineers, and
NC Division of Water Quality. In an email from Chad Coburn dated March 2, 2018, it was
Page 4 of 5

determined that Ditch/Streaml was not part of the Airport's permitted features or a permitted
stormwater conveyance. Because of this determination, a CAMA major development permit is
required for the impacts.
STORMWATER
For Ditch/Stream 1, the Airport is proposing to extend the existing outfall of two pipes that run
under taxiways to the fence line and fill in the existing dich/stream to eliminate the standing
water (wildlife attractant). The existing piped system upstream of the ditch/stream collects
stormwater from the areas shown on the attached map (Attachment 1). The inlets collecting the
stormwater are located in the infield grassed areas between the runways and taxiways and collect
stormwater that is treated via overland flow. The runways and taxiways are described as
Disconnected Impervious Surfaces (DIS) in the Stormwater Design Manual. No new impervious
surface is proposed for this project and no additional runoff from the existing pervious surfaces
will be added to the pipe system. After the existing ditch/stream is filled, the disturbed surface
will be sodded, and stormwater running off the adjacent pavements will flow over the new
grassed areas (overland stormwater flow) to the fence line for a distance of nearly 300 linear feet.
The slope of the grassed area will be between 2 and 3%. This new area will meet Disconnected
Impervious Surfaces Minimum Design Criteria No. 2 Vegetated Receiving Area for
Disconnected Pavement.
The Airport believes that the proposed project will provide a greater water quality benefit than
what currently exists by eliminating erosion from the stream bank and by providing a large
vegetative shoulder/buffer for water flowing off the taxiway pavement to flow across, similar to
the rest of the drainage area to this pipe system. The large grassed area will meet the
requirements of Section (c4) and therefore the Airport believes the project should be "Deemed
Permitted" in accordance with NCGS 143-214.7 (c4) with no requirement to obtain a stormwater
permit (modification) from NCDEQ.
For Ditch/Stream 3, the Airport is proposing to construct triple 72" pipe culverts to connect the
existing triple culverts under Taxiway B and the existing triple culverts under Runway 6-24. The
pipes would be backfilled, and grated inlets installed at the surface. Stormwater will continue to
flow off the adjacent paved areas (Runway 6-24, Taxiway B, and Taxiway G) and into existing
drainage inlets located in the infield area via overland flow. The existing ditch is partially lined
with concrete. Because of this and based on previous discussions with NCDEQ, it is understood
that a stormwater permit is not required for this work at Ditch/Stream 3.
Page 5 of 5

ram., ii'+H:'iF: �.; � •i
EM;I G .24" RCP
D ISTN G 3W RCP
A
PROPOSED JUNCTION BOX WITH
MANHOLE FRAME AND COVER -
RIM 11.50 gin..; ..,i"
Ft,;:4i7:: 5.93
24" INV IN 2.80 I•E.::50 �G'- 0.8
24" INV OUT 2.80 00
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FfEiQ .U:
LEGEND - PROPOSED IMPACTS C?rir _ G:`• ,9. .0
IMPACT #1A
PERMANENT 404 STREAM IMPACT
262 LINEAR FEET It
(3,228 SF)
r , 1''-
IMPACT #113`
PERMANENT NAVIGABLE WATERS IMPACT
30 LINEAR FEET
(465 SF) a ,,
IMPACT #2 4.
PERMANENT WETLAND IMPACT
3,206 SF
(0.07 AC)
ca o
PROPOSED 168 LF 24" ALUMINUM PIPE TO 11 ;` ', 7.0
CONNECT TO PROPOSED 48" ALUMINUM PIPE / I
o i 1
6.0 -
LIMITS OF DISTURBANCE (LOD) E1eMlvir, 6" CHAIN !INK
PROPOSED FILL AREA aptEN CE
r s'
FILL VOLUME = 4600 CY : "-
X � x 30' CAMA AEC
.--x----- . X PROPOSED 48"
ALUMINUM ENDWALL
INV 0.00'
NHWL OF NAVIGABLE WATERS PROPOSED 8' CHAIN LINK FENCE
' :BEHIND NEW ENDWALL
PROPOSED JUNCTION BOX WITH
MANHOLE FRAME AND COVER
RIM 12.00
30" INV IN 0.81
48" INV OUT 0.81
PROPOSED 245 LF 48"
ALUMINUM PIPE TO
CONNECT TO NEW 48"
ALUMINUM HEADWALL
PROPOSED
ENDWALL AND
WI N GWALLS
16'
24'
NCDOT CLASS I RIP RAP �" s
PROPOSED NHWL
GRADE ��, /- ELEV 3.0
NATURAL ---
GRADE
T=15" — LALAYER OF
FILTER FABRIC
NCDOT CLASS I RIP RAP
T = 15"
A = 28 SQUARE YARDS
V = 12 CUBIC YARDS
RIP RAP OUTLET PROTECTION
NOT TO SCALE
NORMAL HIGH WATER OF STREAM
---- PROPOSED 48" X 24" WYE AND
30"
MANHOLE ACCESS RISER
RIM
7.30
24"
INV IN 1.20
48"
INV IN 0.20
48"
INV OUT 0.20
PROPOSED RIP RAP NOTE: SEE FIGURE 3 FOR SECTION VIEWS
OUTLET PROTECTION
TALBERT & BRIGHT
WILMINGTON INTERNATIONAL AIRPORT
FIGURE 2
ENGINEERING& PLANNING CONSULTANTS
WILDLIFE MITIGATION PROJECTTO REMOVE WET DETENTION BASINS
STREAM I IMPACTS
26405
4610 HEI-LEY10-762 DRIVE WILMIPHONE:
AND OTHER STORMWATER IMPROVEMENTS
PLAN VIEW
91N. -
FAX: 91 D-762-6281 PHONE: [phone]
INC LICENSE NO. C-0713 EMAIL: TBIILMOTBIILM.COM
SCALE: 1"=50' MAY S, 201

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ENGINEERING & PLANNING CONSULTANTS
4810 SHELLEY DRIVE NILMINGTON, NC 28405
FAX: [phone] PHONE: [phone]
NC LICENSE NO. C-0713 EMAIL: TBIILM
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WILDLIFE MITIGATION PROJECT TO REMOVE WET DETENTION BASINS
AND OTHER STORMWATER IMPROVEMENTS
1 +00 2+ 00
STREAM 1 IMPACT
SECTION B-B
SCALE: i"=50'
FIGURE 3
STREAM 1 IMPACTS
SECTION VIEWS
15
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MAY 9, 2018

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EDGE OF ASPHALT
PAVEMENT PROPOSED 196 LF TRIPLE 72" ALUMINUM PIPE
(TAXIWAY—"B")
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PERMANENT STREAM IMPACT
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FRAME: 9.0�'
i I.E. 30'I i:P(E): 5.3+
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NEW 36" ALUMINUM STUB OUT
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TALBERT & BRIGHT
ENGINEERING & PLANNING CONSULTANTS
4810 SHELLEY DRIVE WILMINGTON. NC 28405
FAX: [phone] PHONE: [phone]
NC LICENSE NO. C-0713 EMAIL: TBIILM®TBIILM.COM
END 60" HDD-1
PROPOSED 30
MANHOLE ACCESS `.
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NOTE: SEE FIGURE 5 FOR SECTION VIEWS
WILMINGTON INTERNATIONAL AIRPORT
WILDLIFE MITIGATION PROJECT TO REMOVE WET DETENTION BASINS
AND OTHER STORMWATER IMPROVEMENTS
1 "=50
FIGURE 4
STREAM 3 IMPACTS
PLAN VIEW
MAY 9, 2018 1

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SECTION A -A
TALBERT
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ENGINEERING & PLANNING
CONSULTANTS
4810 SHELLEY DRIVE
WILMINGTON, NC 28405
FAX: [phone]
PHONE: [phone]
NC LICENSE NO. C-0713
EMAIL, TBIILM®TBIILM,OOM
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WILMINGTON INTERNATIONAL AIRPORT
WILDLIFE MITIGATION PROJECT TO REMOVE WET DETENTION BASINS
AND OTHER STORMWATER IMPROVEMENTS
1+50 2+00
STREAM 3 IMPACT
SECTION B-B
SCALE: 1 "=50'
FIGURE 5
STREAM 3 IMPACTS
SECTION VIEWS
2+ 50
14
12
10
8
6
4
2
IvI,AY -7, 2018

I --ill -
WILMINGTON INTERNATIONAL AIRPORT
WILDLIFE HAZARD MITIGATION PROJECT - PHASE II
ATTACHMENT 1
A mot__
L
PIPE SYSTEM
DRAINAGE AREA