Oak Island Renourishment Project_Project Narrative

North Carolina Division of Coastal Management
Major Permit Application
2019/2020 Renourishment Project
Oak Island, Brunswick County, North Carolina
September 16, 2019
Proposed by:
Town of Oak Island
Brunswick County, North Carolina
Prepared for:
North Carolina Department of Environmental Quality
Division of Coastal Management
127 Cardinal Drive Extension
Wilmington, North Carolina 28405
Prepared by:
MOFFATT & NICHOL
4700 Falls of Neuse Road
Suite 300
Raleigh, North Carolina 27609

Table of Contents
1.0
INTRODUCTION.................................................................................................................................1
1.1
Background...................................................................................................................................1
1.2
Purpose and Need.........................................................................................................................3
2.0
DECRIPTION OF THE PROPOSED ACTION..........................................................................................5
2.1
Project Description........................................................................................................................5
2.2
Methods of Construction............................................................................................................30
2.3
Sediment Compatibility...............................................................................................................34
2.3.1
Native Beach Sediment.......................................................................................................34
2.3.2
Proposed Borrow Area Sediment.......................................................................................36
2.4
Borrow Area Modeling................................................................................................................40
2.5
Survey Data Collection................................................................................................................42
3.0
CULTURAL RESOURCES...................................................................................................................45
4.0
PROPOSED CONSERVATION MEASURES.........................................................................................45
5.0
COMPLIANCE WITH BRUNSWICK COUNTY AND CAMA LAND USE PLAN.......................................48
6.0
COMPLIANCE WITH THE NC ENVIRONMENTAL POLICY ACT..........................................................48
7.0
CONSTRUCTION EASEMENTS..........................................................................................................49
8.0
REFERENCES....................................................................................................................................49
APPENDIX A — Permit Drawings
APPENDIX B — Sediment Compatibility Analysis & Vibracore Logs
APPENDIX C —Jay Bird Shoals Borrow Area Modeling
APPENDIX D —Stakeholder Meeting Minutes
APPENDIX E — Preliminary Archaeological Assessment
APPENDIX F — Letter of Intent to Obtain Perpetual Easements
ATTACHMENT 1 DCM MP — 1 Application
ATTACHMENT 2 DCM MP — 2 Excavation and Fill
NCDCM Major Permit Application Moffatt & Nichol
2019/2020 Oak Island Renourishment Project September 2019

LIST OF FIGURES
Figure 1-1. Vicinity and Location Map.....................................................................................................
Figure 1-2. Summary of Oak Island Renourishment History....................................................................
Figure2-1. Project Map...........................................................................................................................
Figure 2-2. Oak Island and Bald Head Jay Bird Shoals Borrow Areas ......................................................
Figure 2-3. East End of Renourishment Plan............................................................................................
Figure 2-4. Renourishment Plan..............................................................................................................
Figure 2-5. Renourishment Plan..............................................................................................................
Figure 2-6. Renourishment Plan..............................................................................................................
Figure 2-7. Renourishment Plan..............................................................................................................
Figure 2-8. Renourishment Plan..............................................................................................................
Figure 2-9. Renourishment Plan..............................................................................................................
Figure 2-10. Renourishment Plan............................................................................................................
Figure 2-11. Renourishment Plan............................................................................................................
Figure 2-12. Renourishment Plan............................................................................................................
Figure 2-13. Renourishment Plan............................................................................................................
Figure 2-14. Renourishment Plan............................................................................................................
Figure 2-15. Renourishment Plan............................................................................................................
Figure 2-16. West End of Renourishment Plan........................................................................................
Figure 2-17. Jay Bird Shoals Dredging Plan..............................................................................................
Figure 2-18. Typical Borrow Area Cross Sections.....................................................................................
Figure 2-19. Station 330+00 Equilibrated Construction Template..........................................................
Figure 2-20. Station 370+00 Equilibrated Construction Template..........................................................
Figure 2-21. Station 410+00 Equilibrated Construction Template..........................................................
Figure 2-22. Station 450+00 Equilibrated Construction Template..........................................................
Figure 2-23. Station 480+00 Equilibrated Construction Template..........................................................
Figure 2-24. Typical Renourishment Template Cross Sections................................................................
Figure2-25. Staging Areas.......................................................................................................................
Figure 2-26. Native Sediment Sample Transects.....................................................................................
Figure2-27. Clast Survey Areas................................................................................................................
Figure 2-28. Jay Bird Shoals Borrow Area................................................................................................
Figure 2-29. After dredge bathymetry effects on residual tidal currents over a spring neap tidal cycle
Figure 2-30. Wave induced longshore sediment transport gradients along Caswell Beach shoreline ...
Figure 2-31. Multibeam, Magnetometer, and Sidescan Sonar Survey Coverage ....................................
Figure 2-32. Sub -bottom Grid overlaid with Multibeam Survey.............................................................
Figure 4-1. Post Construction Monitoring of Caswell Beach...................................................................
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LIST OF TABLES
Table 1. Preliminary length and renourishment fill volume......................................................................30
Table 2. Native Beach Characteristics and NCAC Rule Parameters............................................................35
NCDCM Major Permit Application Moffatt & Nichol
2019/2020 Oak Island Renourishment Project September 2019

Table 3. Native beach sediment statistics...................................................................................................35
Table 4. Sediment characteristics of material proposed for placement on Oak Island..............................39
Table 5. Sediment statistics of material proposed for placement on Oak Island.......................................39
Table 6. Composite sediment characteristics of proposed beach fill compared to native sediment ........40
Table 7. Composite sediment statistics of proposed beach fill compared to native sediment..................40
NCDCM Major Permit Application Moffatt & Nichol
2019/2020 Oak Island Renourishment Project September 2019

1.0 INTRODUCTION
1.1 Background
The Town of Oak Island (Town) is located along the Atlantic Ocean, in Brunswick County, NC
between the Cape Fear River Inlet and Lockwoods Folly Inlet. The Town can be accessed by
driving south from Wilmington on U.S. Highway 17 past the towns of Belville and Bolivia, then
following SR 1500 south across the Atlantic Intracoastal Waterway (AIWW) to the Island (Figure
1-1).
The history of renourishment projects on Oak Island dates back to 2001 with the introduction of
the Wilmington Harbor Sand Management Plan (WHSMP). WHSMP refers to the deepening
project administered by the United States Army Corps of Engineers (USACE) and the periodic
maintenance of the harbor entrance. The initial project by the USACE deepened the Wilmington
Harbor in 2001 and placed material along the eastern and western portions of the Oak Island
shoreline. Following the initial project, Oak Island has received beneficial placement of material
from the WHSMP in 2009 and 2018. In 2001 the USACE also conducted a restoration project
across the central portion of the island. The material for this restoration project came from an
upland borrow area called Yellow Banks which unintentionally placed rocks on the beach which
are still present today despite constant removal efforts. In 2009 the USACE dredged the
Lockwoods Folly River Crossing and placed material on western end of Oak Island's shoreline. In
2015 the Town of Oak Island sponsored the Lockwoods Folly Habitat Restoration Project, which
consisted of dredging the Eastern Channel with beneficial placement of compatible material on
the western end of Oak Island's shoreline. After Hurricane Matthew in October 2016, the Town
initiated a dune restoration project to place material along 4.4 miles of shoreline. Earlier in 2019,
material from the Atlantic Intracoastal Waterway (AIWW) at Lockwoods Folly Inlet was
beneficially placed on the western end of Oak Island's shoreline by the USACE. The eastern and
western ends of Oak Island's shoreline experience periodic renourishment as sand is readily
available from the inlets on either end of the island with established programs by the USACE to
dredge them and place material. The central portion of the island has not experienced a
significant renourishment event since 2001. All USACE and Town renourishment project
placement volumes and extents discussed above are shown in Figure 1-2.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
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BRUNSWICK COUNTY
OAK ISLAND RENOURISHMENT PROJECT 2019/2020
OAK ISLAND, NORTH CAROLINA
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TOWN OF OAK ISLAND
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OAK ISLAND, NC 28465
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Figure 1-1. Vicinity and Location Map
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
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Figure 1-2. Summary of Oak Island Renourishment History
1.2 Purpose and Need
The Town is vulnerable to significant damage from minor storms since the overall beach profile
has been lowered substantially; there is essentially no protective dune throughout most of the
oceanfront. Shoreline and dune erosion during Hurricanes Matthew (2016) and Florence (2018)
were particularly significant along the proposed project area. Approximately 586,291 cubic yards
(cy) above -25ft NAVD88, was lost during Hurricane Matthew and 68,072 cy was lost during
Hurricane Florence.
In 2017/2018, as a result of Hurricane Matthew, FEMA provided funding for construction of a
temporary protection measure in the form of an 'emergency berm' which placed approximately
120,000 cy of material in this area to provide immediate protection until a full project could be
completed. With the passing of Florence and Michael in 2018, this emergency material has
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
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served its purpose to provide immediate protection and now needs to be replenished. The
purpose of the proposed project is to provide protection to infrastructure from a 25-year return
period storm event.
From an economic perspective, the need for the proposed 2019/2020 Renourishment project is
to protect and preserve a large portion of the town's infrastructure, tourism industry, and tax
base.
During the proposed beach renourishment project, the Town has several objectives. Those
objectives are summarized as follows:
• Provide protection to ocean susceptible infrastructure and property while maintaining tax
revenues to the Town, County; and State.
• Preservation of the environmental, cultural, and aquatic resources of the Town and
County.
In order for the Town to maintain adequate cash flow, the renourishment of the entire
oceanfront is being completed in separate projects to ensure manageable budgets. This
2019/2020 Renoushishment Project is the first of three planned over the next three years (2019,
2020, and 2021). With the passage of Hurricane Matthew (October 2016) and Hurricane Florence
(September 2018) several funding reimbursements from both the Federal Emergency
Management Agency (FEMA) and the North Carolina Department of Environmental Quality
(NCDEQ) have been received or are expected to be received and used to mitigate for the
extensive erosion experienced from these hurricanes. An upcoming project planned for the
winter of 2020/2021 will be constructed using Post -Florence reimbursements. The final project
planned for winter 2021/2022 will be considered the initial project for the Town's Master Beach
Renourishment Plan. As a result of recent hurricane activity and lack of adequate beach
management, there is effectively no protective dune throughout most of the oceanfront.
Therefore, the first two planned renourishment projects will focus on building a dune to
withstand a 25-year return period storm event across the island. The design also includes a
support pad with a 1V:20H slope which will move MHW seaward on average 80 feet. This is the
Town's immediate need to provide protection to vulnerable infrastructure from the increasingly
active hurricane seasons. The third project planned for winter 2021, will focus on replacing any
dune volume lost in the interim as well as provide additional storm protection in the form of a
recreational berm in front of the dune across the island.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
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2.0 DECRIPTION OF THE PROPOSED ACTION
2.1 Project Description
The proposed project consists of excavating up to 1,100,000 cy (this includes assumed 30%
dredge losses) of beach -quality sediment from Jay Bird Shoals, a borrow area situated a distance
of approximately one mile offshore of the Oak Island/Caswell Beach shoreline (Figure 2-1). As
mentioned previously this will be the first major renourishment project to occur in this area since
2001, the most recent renourishment in this area was 120,000 cy of material for emergency
placement in 2017/2018. Portions of Jay Bird Shoals have been included in previous
renourishment events for the Village of Bald Head Island (Figure 2-2). The closest sail distance
from the borrow area to the placement area is about three miles and the farthest sail distance
from the borrow area to the placement area is about eight miles. The renourishment area will
cover approximately 21,000 ft along Oak Island (Figure 2-3 through Figure 2-16). The complete
set of permit drawings are available in Appendix A.
NCDCM Major Permit Application
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NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
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September 2019

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Figure 2-16. West End of Renourishment Plan
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
21
FOR PERMITTING
Issueo_mig-oa-iE C-1114
EufioE
Moffatt & Nichol
September 2019

Using vibracore data collected in 2019 (1,000 ft spacing), three different zones and cut depths
within the Jay Bird Shoals borrow area have been identified. Since this is an ebb shoal
environment, these three varying cut depths are intended to maintain the integrity of the shoal
and minimize the effect on the nearshore wave environment. Wave modeling was performed to
quantify any potential effects along the Bald Head Island, Fort Caswell, Caswell Beach, and Oak
Island oceanfront (see Section 0). An area of approximately 304 acres within the outer edge of
Jay Bird Shoals has been identified to meet the renourishment requirement of 1,100,000 cy
(Figure 2-17). Typical borrow area cross sections are shown in Figure 2-18. Detailed sediment
characteristics and vibracore logs for the borrow area are provided in Appendix B. Material
placed on the beach will be consistent with NCDCM sediment compatibility standards and will be
visually monitored for sediment quality on a daily basis (via visual inspection) and weekly basis
(via sediment analysis).
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
22

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Figure 2-17. Jay Bird Shoals Dredging Plan
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
23
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Moffatt &Nichol
September 2019

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Figure 2-18. Typical Borrow Area Cross Sections
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
24
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Moffatt & Nichol
September 2019

Sediment will be spread via land -based equipment and shaped into a dune starting at the existing
stable vegetation line. The beach fill will affect approximately 193 acres of beach and inshore
area. The main fill portions of the project will contain approximately 15 — 65 (average = 37) cubic
yards per linear foot (cy/ft) of material. The renourishment template has a dune crest elevation
that varies between 13.5 ft and 14.5 ft NAVD88, the dune crest width is 6 ft, with front and back
slopes of the dune being 1V:5H. The dune will break at elevation 7 ft NAVD88 and then continue
out on a 1V:20H slope until it ties into the existing profile somewhere between elevation -1.0 ft
and -10.0 ft NAVD88. This foreshore slope was chosen to best replicate the natural slope of the
beach in efforts to mitigate significant profile equilibration directly after placement; however,
mild equilibration of the profile is still expected. To quantify the extent of equilibration, the
placement template at five representative locations within the placement area were chosen and
run in SBEACH. The output profile from the 2-yr storm was used as an assumption of the resulting
equilibrated construction template and are shown in Figure 2-19 through Figure 2-23. Material
placed in the dune and berm will be transported to the offshore bar. Mild equilibration of the
dune profile is expected; however, this will act as a sand source for the berm over time. The
equilibrated template will maintain a similar recreational beach width when compared to the
2016 (Pre -Matthew) conditions when a dune was present within the project area.
330+00 Construction Template: SBEACH Equilibration
18
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0 100 200 300 400 500 600 700 800
Distance from Baseline (ft)
- - - - - - Construction Template Equilibrated Construction Template
Pre -Construction Profile Structure Location
Figure 2-19. Station 330+00 Equilibrated Construction Template
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
25

370+00 Construction Template: SBEACH Equilibration
18
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----- Construction Template Equilibrated Construction Template
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Figure 2-20. Station 370+00 Equilibrated Construction Template
410+00 Construction Template: SBEACH Equilibration
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Pre -Construction Profile Structure Location
Figure 2-21. Station 410+00 Equilibrated Construction Template
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
26

450+00 Construction Template: SBEACH Equilibration
18
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0 100 200 300 400 500 600 700 800
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----- Construction Template Equilibrated Construction Template
Pre -Construction Template Structure Location
Figure 2-22. Station 450+00 Equilibrated Construction Template
480+00 Construction Template: SBEACH Equilibration
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Figure 2-23. Station 480+00 Equilibrated Construction Template
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
27

This dune has been designed to withstand a 25-year return period storm event. This
renourishment template design is shown in Figure 2-24. Taper sections which are approximately
500 ft long will tie the main fill into the natural shoreline at the ends of each reach. The dune
will be planted with summer grasses with plants being installed on 18" centers. A summary of
the renourishment placement and fill is shown in Table 1.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
W

E6NiTING OCCNPS ON
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TYPICAL BEACH SECTION WITH QUNE (135' NAVD88)
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TYPICAL BEACH SECTION WITH DIJNE(14.0' NAVD88)
(STATIONS 300+00-330+00, 460+00 - 500+00)
Figure 2-24. Typical Renourishment Template Cross Sections
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
29
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FOR PERMITTING
ISSUED. 201&0&15 C-302
Ea�go
Moffatt & Nichol
September 2019

Table 1. Preliminary length and renourishment fill volume
Approximate
Average Unit
Reach
Renourishment
'Reach
Project
Geographic
Fill Volume
Volume
Reach
Length (ft)
Station
Location
(cy/ft)
(cy)
Oak Island East
300+00 to
SE 63rd St to 10tn
21,000
37.0
846,000
and Central
500+00
Place W
'Reach length includes 500-ft taper section at the beginning and end of reach.
2.2 Methods of Construction
The proposed project would involve use of either a hopper dredge or a cutter suction (hydraulic)
dredge to excavate sand from Jay Bird Shoals borrow area.
Hopper dredges are self-propelled vessels that employ trailing suction draghead(s) to remove
sediment from the seafloor. The draghead is equipped with various types of steel cutting teeth
or blades and/or high-pressure water nozzles that dislodge thin layers (approximately one to
three feet deep) of sediment from the seafloor. A mixture of loose sediment and water is
pumped through a suction pipe into a hopper onboard the dredge. Sediment settles in the
hopper and excess water is discharged via an overflow system (i.e., scuppers). Once fully loaded,
the hopper dredge would travel from the borrow area to a nearshore pump -out station along the
target beach.
As specifically described by Hales (1995) the proposed methodology includes removing dredged
material from the hopper dredge, where the dredge moors to a nearshore pump -out station
which is typically an anchored floating structure, buoy, or multiple buoy berths. The nearshore
pump -out station will be situated in 25' to 35' of water and an underwater pipeline will extend
from the pump -out station to shore. A hose is connected from the pump -out station to the
hopper -dredge discharge manifold. The dredge then mixes the dredged material with water to
form a slurry and pumps the slurry from its discharge manifold through the floating hose to the
anchored floating pump -out station and on through the underwater pipeline toward shore where
it would be pumped onto the recipient beach (Hales 1995). Once empty, the dredge would then
return to the borrow area and the cycle of dredging and discharging would be repeated.
Equipment refueling would occur as needed by fuel barge or at the Port of Wilmington. The
position of the nearshore pump -out station and underwater discharge pipeline would be
relocated as necessary as construction progresses along the beach.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
30

Cutter suction dredges are stationary dredges that are moored at the borrow site by either spuds
or a series of anchors and wires. The equipment employs the use of a rotating cutterhead that
loosens the material from the sea floor. Just behind or within the cone of the cutterhead is a
suction pipe that gathers the loosened material from the sea floor in a material and water mixture
called a slurry. The cutter suction dredge (CSD) is connected to a pipeline that stretches from the
borrow area to the final placement location via a series of floating and submerged pipelines.
Generally, a CSD will have approximately 1,500 feet of floating hose/pipeline directly connected
to the stern of the dredge. This floating pipeline allow the dredge to move throughout the
borrow area to dredge/gather the material. This floating pipeline is connected to a submerged
pipeline that is laid along the sea floor from the borrow area to the recipient beach. The
submerged pipeline is connected to land -based pipelines that helps to distribute the material
throughout the beach placement area. Additional subline would be added in the borrow area
should the 1,500 feet of floating line not allow the CSD to reach all permitted dredging areas.
To collect the material the CSD swings the bow of the dredge (cutterhead) back and forth within
the borrow site in an arc like pattern moving the dredge forward a few feet with each swing of
the dredge. The cutterhead is engaged/buried within the seafloor to a depth of approximately
two to eight feet (depending on the allowable cut depth) while swinging back and forth. The
material that is loosened becomes fluidized and is pulled into the suction pipe in a slurry and is
pumped directly to the recipient beach through the series of pipes described above.
A couple of primary differences between the hopper dredge and the CSD is the hopper dredge
removes the material in thin layer passes and may take multiple passes in order to reach the
desired depth; the CSD will take all available material to the desired depth in one pass and
generally does not cover an area twice. Also, a hopper dredge needs deeper water to operate
within the borrow area because material loads into a hopper on the vessel, for transport, which
dramatically increases their draft during the loading cycle. Since the CSD is directly pumping the
material onshore the draft of the vessel does not change and therefore can operate in much
shallower waters.
Placement and grading activities on the beach would involve the use of bulldozers to redistribute
and grade the beach fill material to the proposed beach profile. Land -based equipment will be
brought to the site over public roads and will enter the beach at existing permanent beach
accesses and can be stored at staging areas shown on Figure 2-25. Existing vegetation on the
beach will be avoided and preserved; however, any alteration of vegetation necessary for
equipment access will be repaired to pre -project conditions. Daily equipment staging will be on
the constructed beach seaward of the dune line. Construction contracts will provide for proper
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
31

storage and disposal of oils, chemicals, and hydraulic fluids etc. necessary for operation in
accordance with state and federal regulations.
Work will progress in sections within the borrow area and along the beach. Fill placement along
the beach will typically progress at a rate of 400-700 linear feet per day. Construction activities
will involve movement of heavy equipment and pipe along approximately 1 mile reaches over a
period of 1-2 weeks. Once a section is complete, piping and heavy equipment will be shifted to
a new section and the process repeated. As soon as practicable, sections will be graded and
dressed to final slopes. Other than at temporary equipment staging areas, residents and visitors
along the project area will not experience significant disruption to recreational activities except
within the immediate construction area. Existing public access to the beach will remain open at
all times during construction. Offshore pump -out stations and appurtenances would not affect
commercial or recreational boating.
The proposed project involves dredging and placement of approximately 1,100,000 cy of beach -
quality sand. Based on other project experiences, one hopper dredge can excavate and place on
the order of 10,000 — 15,000 cy in a 24-hour period. Dredging and grading would occur around
the clock, thus requiring nighttime lighting on the beach and onboard the dredge. All beach fill
construction activities would take place within the 16 November through 30 April environmental
window. It is anticipated the proposed construction will be accomplished in approximately three
months, unless multiple dredges are deployed on the project which would shorten the
construction period.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
32

Figure 2-25.Staging Areas
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
33
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Moffatt & Nichol
September 2019

2.3 Sediment Compatibility
2.3.1 Native Beach Sediment
Sediments on the native beach were sampled by Athena in 2019. This established a native grain
size distribution for purposes of compatibility analyses. The native sediment distribution for Oak
Island was defined based on the percent gravel, granular, sand, fine-grained, and calcium
carbonate present in samples taken from 13 locations along a specific transect as specified in
North Carolina Administrative Code 15A NCAC 07H.0312 (1). These 13 samples were then
averaged to obtain a composite average for that transect. Eleven (11) transects were sampled
along the shoreline of Oak Island (Figure 2-26). The composite average for each of the 11
transects were then averaged to obtain a global mean for the native beach. As mentioned above,
this is the first of three projects planned over the next three years (2019-2022) to renourish the
entire oceanfront. The composite average from all eleven transects will be used to classify native
material as opposed to only using the composite average for the transects that fall within the
project area. This establishes consistent standards for native grain size for the future projects. A
summary of the distribution and statistics for the native sediment is provided in Table 2. The
table also demonstrates the acceptable grain size criteria for beach placement in accordance with
15A NCAC 07H.0312 (3). The native material is characterized as fine-grained sand under the
American Society for Testing and Materials (ASTM) Unified Soil Classification System with a mean
grain size of 0.27 millimeter (mm). The native beach is medium -grained sand that is coarse
skewed and moderately sorted (Table 3).
ll n
Legend
— Nnva Sample Lo lnns
—Tl ftw lLgnbans
2.500 S.OUO t0.000 _
Feet —
Figure 2-26. Native Sediment Sample Transects
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
34

Table 2. Native Beach Characteristics and NCAC Rule Parameters
Characteristic
2019 Native
Global Mean
NCAC
Requirements
NCAC Maximum
Gravel (>#4)
Reported: 0.45%
native + 5%
<_ 6%
Granular (>#10 & <#4)
Reported: 0.71%
native + 10%
<_ 11%
Sand (>#230 & <#10)
Reported: 96.96%
-
-
Fines (<#230)
Reported: 1.88%
native +5%
<_ 7%
Calcium Carbonate
Reported: 9.72%
native + 15%
<_ 25%
Table 3. Native beach sediment statistics
Sediment
Compatibility
2019 Native
Global Mean
Median (mm)
0.26
Median ((�)
1.97
Mean (mm)
0.27
Mean ((�)
1.90
Standard
Deviation (o4))
0.81
Moffatt and Nichol conducted a field investigation on May 14, 2019 to estimate the total number
of shell and rock material greater than or equal to three inches in diameter, observable on the
surface of the beach between mean low water and the frontal dune toe, in a 50,000 square foot
area based on requirements of 15A NCAC 07H.0312. Investigations were performed in three
locations across Oak Island shown in Figure 2-27. The three locations were chosen as they have
experienced various levels of renourishment activities, an average from the three areas will be
calculated to represent the entire oceanfront. Area 1 was located between Stations 650+00 and
670+00. Area 2 was located between Stations 490+00 and 500+00. Area 3 was located between
Stations 210+00 and 230+00. Area 1 was nourished two months prior to the investigation, Area
2 had not been nourished since 2001, and Area 3 had received nourishment in the summer of
2018. Results of the investigation found 165 pieces in Area 1, 44 pieces in Area 2, and 87 pieces
in Area 3 of shell material greater than or equal to three inches in diameter. It was observed at
the time of the investigation that a recent dune pushing effort had taken place within Area 2
which probably influenced the low number of clasts surveyed assuming that the characteristic
shell material was pushed up into the dune and not counted. The average clast count of shell
and rock material greater than or equal to three inches in diameter of the three areas surveyed
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
35

is 99 pieces. As mentioned previously, this is the first of three projects planned over the next
three years which will renourish the entire oceanfront, the average from the three areas
surveyed will be used to determine the clast count as opposed to only using the area surveyed
that falls within the project area, especially since the Area 2 clast count was low due to an recent
dune pushing effort. This establishes consistent clast count standards for future projects to use.
Figure 2-27. Clast Survey Areas
2.3.2 Proposed Borrow Area Sediment
Vibracores in the Jay Bird Shoals borrow area were obtained by AVS in February and March of
2019. Figure 2-28 gives the location of vibracores and the bathymetry of the proposed borrow
area within Jay Bird Shoals. Using a multibeam bathymetric survey collected by Geodynamics in
2019, volume calculations indicate 2.95 million cubic yards (Mcy) of material exists in the three
(3) zones within the Jay Bird Shoals borrow area. While 846,000 cy is the expected template
placement volume, the anticipated dredge volume could reach 1,100,000 cy due to losses
typically incurred between what is dredged and what is placed (up to 30%).
When Geodynamics collected the multibeam survey in of 2019, magnetometer data was also
collected. A magnetometer anomaly in the form of a line running northeast to southwest across
the borrow area was identified. The anomaly did not appear on the sidescan or subbottom
surveys meaning the resolution was too fine to capture. The anomaly does not present itself as
a cultural resource, it is likely a cable or pipe. At this point a minimum 50 ft buffer on both sides
of the anomaly is being proposed to avoid it (Figure 2-28).
The borrow area was divided into three (3) zones as beach compatible material exists down to
varying elevations across the shoal. The dredge elevation within these zones was decreased
moving onshore over the shoal to replicate the natural contours of the shoal system. Zone 1
contains beach compatible material down to an elevation between -32 ft and -40.5 ft NAVD88.
The design elevation within this zone is set to -26 ft NAVD88. Zone 2 contains beach compatible
material down to an elevation between -39.5 ft and -41.5 ft NAVD88. The design elevation within
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
36

this zone is set to -31 ft NAVD88. Zone 3 contains beach compatible material down to an
elevation between -33 ft and -38 ft NAVD88. The set dredge elevation within this zone is set to -
27 ft NAVD88. The average cut depth across Zone 1 and Zone 2 is 5.8 ft, and Zone 3 is 6.9 ft.
Since this is a shoal environment, these shallower cut depths are intended to keep the integrity
of the shoal intact by not allowing waves to break closer to shore and cause unintended effects
on the nearshore environment. The sediment characteristics and statistics are presented in
Table 4 and Table 5. As noted in the tables the sediment characteristics and statistics presented
consider a composite average down to the design elevation for each zone.
Appendix B provides a summary table of sediment descriptions including; mean grain size,
percent gravel, percent granular, percent fines (<#230), percent carbonate, and Munsell color.
The composite averages shown in Appendix B will be different than the composite averages
shown in Tables 4 and 5. Appendix B shows the composite average for the entire vibracore
sample, while Tables 4 and 5 show the composite average for the vibracore down to the design
elevation for each zone. The borrow area vibracores meet all the grain size criteria for beach
placement as established in 15A NCAC 07H.0312 (Table 6). The typical sediment type in Jay Bird
Shoals is medium -grained sand (mean size = 0.33 mm) that is coarse skewed and poorly sorted.
This preliminary comparison shows the proposed borrow area sediments to be similar to the
native material (Table 7).
Although no documented State or Federal criteria for sediment color exist, the United States Fish
and Wildlife Service has recommended that to minimize effects on turtles that the Munsell color
be at least a 5. The Jay Bird Shoals vibracore Munsell colors vary from gray (10YR-5/1, 10YR-6/1)
to light gray (10YR-7/1), some grayish brown (10YR-5/2) to light grayish brown (10YR-6/2). In
Appendix B there are two colors noted for the vibracore samples, one while the sample was still
wet and one after the sample had been exposed to the sun and allowed to dry for a month.
Material placed on the beach will be visually monitored for sediment quality and color on a daily
basis (via visual inspection) and weekly basis (via sediment analysis).
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
37

4000 2286000 2288000 2290000 2292000 2294000
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7
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Dredge Elevation
Volume Including
Zone
(k NAVD88)
Volume (Cy)
50 ft Buffer (cy)
Zone 1
-26.0
859,851
859,851
Zone 2
-31.0
920,976
908,846
Zone 3
-27.0
1,276,591
1,185,475
Total
3,057,417
2,954,171
�6 2
4
8
2284000 228fi 000 2288000 2290000 2292000 2294000
Legend Elevation (ft. NAVD88)
• Jay Bird Shoals Vfbracores -16 - -14 -24 - -22
Mag Anomaly -18 - -16 -26 - -24
50ft Mag Buffer -20 - -18 Ilia. -28 - -26
Jay Bird Shoals Borrow Area -22 - _20 = -29 51 - -28
r
• `,� ice; N
r y, 0 750 1,500 3,000
Feet
Figure 2-28. Jay Bird Shoals Borrow Area
0
NCDCM Major Permit Application Moffatt & Nichol
2019/2020 Oak Island Renourishment Project September 2019
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Table 4. Sediment characteristics of material proposed for placement on Oak Island
Sediment
Zone 1 Dredge Elevation -26 ft NAVD88
Zone 2 Dredge Elevation -31 ft NAVD88
Zone 3 Dredge Elevation -27 ft NAVD88
Compatibility
JB-20
JB-21
JB-22
JB-23
JB-01
JB-06
JB-17
JB-18
JB-07
JB-08
JB-11A
JB-12
JB-13
Gravel
2.64%
0.81%
1.56%
0.13%
2.99%
1.06%
0.70%
1.85%
2.68%
0.83%
3.30%
0.92%
3.06%
Granular
5.78%
1.71%
3.03%
0.70%
4.93%
3.06%
2.63%
8.51%
6.01%
3.24%
6.25%
2.68%
4.87%
Sand
85.19%
94.56%
90.12%
96.90%
86.20%
89.35%
91.61%
85.04%
85.33%
91.91%
85.63%
92.25%
87.11%
Fines
6.39%
2.92%
5.29%
2.27%
5.89%
6.53%
5.06%
4.61%
5.98%
4.01%
4.82%
4.15%
4.96%
Carbonate
18.20%
19.30%
12.07%
7.85%
8.45%
13.37%
12.23%
21.20%
9.72%
10.03%
18.50%
7.79%
15.46%
Median (mm)
0.23
0.29
0.25
0.22
0.29
0.23
0.25
0.26
0.24
0.28
0.24
0.21
0.28
Mean (mm)
0.34
0.31
0.32
0.25
0.39
0.30
0.30
0.38
0.36
0.33
0.35
0.28
0.39
Note: characteristics represent the composite average down to specified zone dredge elevation.
Table 5. Sediment statistics of material proposed for placement on Oak Island
Sediment
Zone 1 Dredge Elevation -26 ft NAVD88
Zone 2 Dredge Elevation -31 ft NAVD88
Zone 3 Dredge Elevation -27 ft NAVD88
Compatibility
JB-20
JB-21
JB-22
JB-23
JB-01
JB-06
JB-17
JB-18
JB-07
JB-08
JB-11A
JB-12
JB-13
Median (mm)
0.23
0.29
0.25
0.22
0.29
0.23
0.25
0.26
0.24
0.28
0.24
0.21
0.28
Median (4))
2.15
1.81
1.99
2.16
1.81
2.14
2.00
1.92
2.04
1.84
2.04
2.24
1.83
Mean (mm)
0.34
0.31
1 0.32
0.25
0.39
0.30
1 0.30
0.38
0.36
1 0.33
0.35
0.28
0.39
Mean (co)
1.56
1.69
1.66
1.99
1.34
1.75
1.72
1.40
1.47
1.58
1.52
1.84
1.36
Standard
Deviation (off)
1.75
1.14
1.38
0.90
1.60
1.42
1.11
1.61
1.75
1.36
1.68
1.37
1.65
Note: statistics represent the composite average down to specified zone dredge elevation.
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Moffatt & Nichol
September 2019

Table 6. Composite sediment characteristics of proposed beach fill compared to native sediment
Sediment
Compatibility
2019 Native
Global Mean
NCAC
Maximum
Jay Bird Shoals
Composite
Gravel
0.45%
<_ 6%
1.64%
Granular
0.71%
<_ 11%
3.88%
Sand
96.96%
-
89.72%
Fines
1.88%
<_ 7%
4.77%
Carbonate
9.72%
<_ 25%
12.53%
Median (mm)
0.26
-
0.25
Mean (mm)
0.27
-
1 0.33
Note: characteristics for Jay Bird Shoals composite average down to specified zone dredge elevations.
Table 7. Composite sediment statistics of proposed beach fill compared to native sediment
Sediment
2019 Native
Jay Bird Shoals
Compatibility
Global Mean
Composite
Median (mm)
0.26
0.25
Median ((�)
1.97
1.99
Mean (mm)
0.27
0.33
Mean ((�)
1.90
1.60
Standard
0.81
1.46
Deviation (6(�)
Note: statistics for Jay Bird Shoals composite average down to specified zone dredge elevations.
2.4 Borrow Area Modeling
In order to investigate the potential effects of dredging material from a Jay Bird Shoals borrow
area identified for the 2019/2020 Renourishment Project on neighboring shorelines of Caswell
Beach and Bald Head Island, numerical models were developed to investigate hydrodynamics,
waves, and sediment transport using Deltares' Delft3D model suite. The hydrodynamics and
wave models were successfully calibrated and validated against available observed water levels,
currents, discharges, and wave data. The sediment transport model was not calibrated due to
lack of measured data to calibrate against.
Tidal current, wave, and sediment transport modeling was performed for the existing and after -
dredge bathymetry scenarios. Two borrow area after -dredge templates were considered.
Template 1 was designed to dredge 2.95 million cubic yards (mcy) and Template 2 was designed
to dredge 2.34 mcy of available beach compatible material. For both after -dredge templates only
NCDCM Major Permit Application
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part of the material, 1.034 mcy, will be dredged for the 2019/2020 Renourishment Project. Thus,
within the proposed borrow area, the results from the Delft3D model are believed to be a
conservative overestimate of the potential effects on the tidal current and wave climates.
The tidal current model results indicate that for both after -dredge bathymetry templates effects
on residual tidal currents would be localized and small. This implies there would be no significant
effects on sediment transport processes associated with tidal currents. Figure 2-29 below shows
the effects of the two after -dredge bathymetry templates on residual tidal currents over a spring -
neap tidal cycle.
Figure 2-29. After dredge bathymetry effects on residual tidal currents over a spring neap tidal cycle
The wave transformation model results for the 2004 — 2018 average annual offshore wave
climates show that the two after -dredge bathymetry templates could result in a slight
redistribution of wave energy along the shoreline during moderate to severe storm events.
Sediment transport modeling was also completed, to observe if the changes to wave heights and
wave directions would affect the longshore transport. The sediment transport modeling results
for both after -dredge bathymetry templates show that the wave -induced longshore sediment
transports could be reduced leeward of the borrow area but could potentially increase on
shoreline segments both east and west sides of the borrow area. The net effect of these changes
could result in localized adjustments in shoreline erosion / accretion. Based on the model results
of the longshore sediment transport gradients as presented in Figure 2-30 below, most of the
potential increases in shoreline erosion would be limited to discrete portions of Caswell Beach
(between survey transects 37+00-60+00 and 150+00 — 170+00). Generally, both templates show
results close to existing conditions, with some areas above and below existing. There is no strong
evidence to choose one template over the other given the model results, especially given that
this is not a morphological model. The modeled sediment transport inside the surf zone is greatly
influenced by the imposed model bathymetry. Thus, the model results only represent the
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
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bathymetric condition constructed based on the available data sources. There will be an
additional 0.6 mcy beach compatible material available in Template 1. For this reason, Template
1 was chosen for the Town of Oak Island's permit application for the 2019/2020 Renourishment
Project. The Town of Oak Island will monitor the Caswell Beach shoreline for nine (9) years post -
project to investigate any potential effects which might require mitigation. The complete borrow
area modeling report is available in Appendix C.
Cx0
`m
40
c
4 70
C
F
E .24)
-40
0
-60
-$0
-1rjn
VV
+ Caswell Beach Transects
—Transport G rad6ent - After -Dredge Template 1
—Transpnrt0,radeint-After-Dredle Template -------- ---------7-_==_-----------------------.
I I
—4 "1 1W Q* a "A R LAD $ %Ilk R * ifi�
1 I 1 ! I I
1 I 1 Y I I
Y I Y !
I I
I
--------
! I I I I I I
I I I
--{--_-_-__-}__-_-_=--r_--=_-__ _ ___ -- _--____-___,
=i-=l-_--= I I Ja'1 Bird Shuiy;row Site
Y I F I I I I I
I I I I I I I
I
! 1
Y I I
Y
F I
I ! I I I I
! I ! 1 I I I I
69200D 693000 694000 695cm 6950W 697000 69B00Q 699000 7000M 7010M
Easting - NC State Plan (m)
Figure 2-30. Wave induced longshore sediment transport gradients along Caswell Beach shoreline
The Town hosted a meeting in August 2019 to discuss the 2019/2020 Renourishment Project with
neighboring stakeholders (Caswell Beach, Fort Caswell, and the Village of Bald Head Island) in
which the preliminary modeling results were discussed. The meeting minutes are provided in
Appendix D.
2.5 Survey Data Collection
15A NCAC 07H.0312 (2) specifies 100 percent multibeam and sidescan sonar coverage of the
borrow area and geophysical imaging of the seafloor on survey grids with line spacing not to
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exceed 1,000 feet. Geodynamics completed a survey of the Jay Bird Shoals borrow area in June
2019. Data collected included; magnetometer, sidescan sonar, sub -bottom, and multibeam.
Based on the results of the magnetometer data, shown in Figure 2-31 below, the data was
reviewed by Tidewater Atlantic Research, Inc. in order to determine the presence and proper
avoidance of any cultural resources. This is discussed further in Chapter 3.0 Cultural Resources.
The multibeam data collected, also shown in Figure 2-31 below, was used to determine the total
dredge volume for the borrow area. The sidescan sonar mosaic data in Figure 2-31 illustrates the
differences in bottom type throughout Jay Bird Shoals. The sub -bottom data was collected on
grid line spacing of 1,000 ft., see Figure 2-32 below, which shows a 3D diagram illustrating the
sediment horizons, overlaid on the data is the multibeam data where warm colors are shallow
and cool colors are deep.
NCDCM Major Permit Application
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Legend
41_P2_J ay bird_Sft_n avo BB
Value
= High :-14.6785
d= .rn 28.5112
0 500 1,000 2.000 3,000 a 000
FEeI
Legend
Mag Prellm Grid
Norm P, H Gamma Range $
�. nign 6 '3
�cr 6 3
$ ' F ❑ 10�
9.
0 �_tp rOw
•3
$ t(
f0
� -7 -101 -I'
3 -1a .10
a -10I -1pc-i�
7 J r it
,10
-10 $ 10 •10 -10 -10f-1 a
r3 :� -10 -Job
.10
3'to
3 31 3 -1() 3 3 3 3 3- 3 10 •1p'Ic
3 3 y1)I
3 3 �
3 04e
�3 fAj3 3 111
�-0 .3
3 / 3
�3 e3 3
R1}0 3 .5 3 3 ' 1 ]
• 3 -1d -30
0
.1p'�.0 4'3 '3 -6 3
3 .3
Figure 2-31. Multibeam, Magnetometer, and Sidescan Sonar Survey Coverage
NCDCM Major Permit Application
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Moffatt & Nichol
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44

For reference .. ,• �-�� � ; ...,.. ... :,»
Z-Exageration @ 8.2
Vertical
�`Datum NAVD88
Figure 2-32. Sub -bottom Grid overlaid with Multibeam Survey
3.0 CULTURAL RESOURCES
A series of underwater archaeological studies and surveys have been conducted by the NC
Underwater Archaeological Branch and the US Army Corps of Engineers within the vicinity of the
Cape Fear River inlet (USACE 2010). The NC State Historic Preservation Office was consulted prior
to offshore geotechnical investigations to ensure vibracores collected would not interfere with
any known cultural resources. Tidewater Atlantic Research, Inc. conducted an evaluation of all
magnetic anomalies resulting from the magnetometer survey. Results identified eleven targets
consisting of a tire, several small objects (i.e. traps), and deteriorated buried wire or cable
(Appendix E). In order to avoid dredging and placement of the marine debris during construction,
a minimum 50-foot buffer (on both sides) was developed around the largest debris field (as
shown in Figure 2-28).
4.0 PROPOSED CONSERVATION MEASURES
The following conservation measures will be implemented to avoid or minimize potential impacts
on the affected environment and federally managed species. In addition to those listed below,
the Town is committed to Reasonable Prudent Measures and Terms and Conditions listed under
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
45

sand placement from beach nourishment activities (A) in the US Fish and Wildlife Statewide
Programmatic Biological Opinion for Sand Placement Projects (USFWS 2017).
Construction Schedule
• All sand placement, dredging, and associated construction activities would adhere to a 16
November to 30 April environmental window. Adherence to the environmental window
would minimize potential impacts by avoiding the following periods of critical biological
activity:
o Sand placement and dredging operations would avoid most of the peak
recruitment period [March -September (Hackney et al. 1996)] for surf zone fishes
in NC.
o Dredging operations near the Cape Fear River inlet would avoid peak larval ingress
periods [May -June (Hettler and Chester 1990)] for estuarine -dependent fishes and
invertebrates, thereby reducing rates of larval entrainment during dredging
operations.
o Sand placement operations would avoid peak spring benthic invertebrate
recruitment periods in NC [May through September (Hackney et al. 1996, Diaz
1980, Reilly and Bellis 1978)]; thereby reducing the duration of direct impacts on
intertidal beach benthic infaunal communities that constitute the prey -base for
demersal surf zone fishes.
o Borrow area dredging operations would avoid peak spring benthic invertebrate
recruitment periods in NC [May through September (Hackney et al. 1996, Diaz
1980, Reilly and Bellis 1978)]; thereby reducing the duration of direct impacts on
subtidal soft bottom benthic invertebrate communities that constitute the prey -
base for nearshore demersal fishes.
Construction Methods
• Good Engineering Practices (GEPs) and Best Management Practices (BMPs) would be
applied to all sand placement and dredging activities.
Sand Placement
• Pipelines will be equipped with spreaders to reduce effluent discharge velocities during
sand -slurry placement. Temporary longitudinal sand dikes would be used to contain and
NCDCM Major Permit Application
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Moffatt & Nichol
September 2019
46

direct the horizontal flow of the discharged sand -slurry along the beach. These measures
would maximize sediment retention within the designated placement area, thereby
minimizing potential surf zone turbidity effects.
• Sand delivery pipelines will be routinely inspected for pressurized leaks, and any leaks
that are found would be immediately repaired.
Dredging
• A hydrographic survey covering the entire area where the dredge is expected to operate
will be conducted before and after the dredging event.
• Dredging contractors will be required to maintain spill control plans and waste
management plans for all dredging fleet equipment.
Sediment Compatibility
• All material placed on the beach and in associated dune systems would consist of beach
compatible sand that meets NCTechnical Standards for Beach Fill Projects (15A NCAC 07H
.0312). Monitoring of fill material at the pipeline outfall will be conducted throughout
sand placement operations. If dredging operations encounter non -compatible material,
the contractor will cease operations and immediately contact the USACE Wilmington
District Regulatory Branch and the NCDCM to determine the appropriate course of
corrective action. The use of only sand that is compatible with the native beach would
reduce the extent and duration of direct impacts on intertidal beach benthic infaunal
communities and sea turtle nesting.
Post -Construction Monitoring
• The Town of Oak Island will monitor the Caswell Beach shoreline annually for nine (9)
years post -project to investigate any potential effects which might require mitigation.
Figure 4-1 below shows the extents of the monitoring. For comparison the figure also
shows the extents of Bald Head Island's monitoring efforts on Caswell Beach in
association with their borrow area in Jay Bird Shoals.
NCDCM Major Permit Application
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Moffatt & Nichol
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2255000 2260000 2265000 2270000 2275000 2280000 2285000 2290000 2295000 2300000 2305000
S0tTHP0AT -
rnni0 rnvcae - ..__ - -----' rnNK --'---
-------�assF�RE'
I•
9omer Slough _ nm .,� dfn 1
Pr:acurr, ��
TANK, 6c 3Btt
_ a2tt
6s \no
0
21q FR33k
N Fr�q JOLg v
-- -__ oak tsfand's Existing
'
aso �q
N N M 20 p +O \O o L 1
Mo
s w -_ nitoii' FI v, "I+ o a n '
oGN�SOA�`? z
33 32 nBExtent °
v 00 b o
- _ 2e aklslan p eqq*z� F, s
3a oacl 33 ....31 -__.._ v .,'dam Caswell Monttoririg:Eztent x ox o,4_ fz ,.
e
......
5' Haven 31 ...
sh ,t(s \E�
0lJ 25134 Wtmlr�i
$a-HhM
o
34 21
eadObstns oo+n- to.�rn '
74 C ,a�.s cwel
a4 as za asQfoo
37 n5I�f nOg xt
27 2 io iso2`szarc- ; �Ys; ent q
_97 36 82 �� 9 r -
,pJai�-J� 11 -!; ��y/ Towers
d Lt Hoj
Obstr 33 37 3S 34 i 26 \_/ b 1 ✓- / CO FiF .
Fsh Naver 97 29 20
burn �nir 20 rU I / z a oz Bald Head
FJ/F
R255
_ 7i �1�; i4
30 32 3i�'
�33�
--„7—� 36 55,
39
sR 11 Say 3
_
14 26'Ohstn 19.
40 `_16.v-
2255000 2260000 2265000
�
2270000 2275000 2200000 2285000 2290000 2295000 2300000 2306001)
Legend
Monitoring Transects
;
Bald Head Island Jay Bird Shoals Borrow Area
&
h,.
Oak Island Jay Bird Shoals Borrow Area
V
0 2,500 5,000 10,000 15,000
Feet
Figure 4-1. Post Construction Monitoring of Caswell Beach
5.0 COMPLIANCE WITH BRUNSWICK COUNTY AND CAMA LAND USE PLAN
The proposed project is consistent with the approved CAMA Land Use Plans for Brunswick County
and the Town of Oak Island. The project property is within the planning jurisdiction of Brunswick
County and the Town of Oak Island and is classified "Developed" by the CAMA Land Use Plan.
6.0 COMPLIANCE WITH THE NC ENVIRONMENTAL POLICY ACT
The Division of Coastal Management has determined prior to the application that review of this
project under SEPA is not be required.
The North Carolina Division of Water Resources will be provided a full copy of the permit
application requesting a 401 Water Quality Certification.
NCDCM Major Permit Application
2019/2020 Oak Island Renourishment Project
Moffatt & Nichol
September 2019
M.

7.0 CONSTRUCTION EASEMENTS
The Town is in the process of obtaining easements for the oceanfront properties within the
project area. The Town has provided a letter of intent to obtain these easements prior to
construction (Appendix F).
8.0 REFERENCES
Diaz, H. 1980. The mole crab Emerita talpoida (say): A case study of changing life history pattern.
Ecological Monographs 50(4):437-456.
Hackney, C.T., M.H. Posey, S.W. Ross, and A.R. Norris. 1996. A review and synthesis of data on
surf zone fishes and invertebrates in the South Atlantic Bight and the potential impacts from
beach renourishment. UNC-Wilmington, Wilmington, NC, 111 pp. Prepared for: Wilmington
District, US Army Corps of Engineers.
Hales, L.Z. 1995. Dredge Plant Equipment and Systems Processes; Summary Report for Technical
Area 3. Technical Report DRP-95-10, United States Army Corps of Engineers
Hettler, W.F. and A.J. Chester. 1990. Temporal distribution of ichthyoplankton near Beaufort
Inlet, North Carolina. Marine Ecology Progress Series 68: 157-168.
Reilly, F.J. Jr., and V.J. Bellis. 1978. A study of the ecological impact of beach nourishment with
dredged materials on the intertidal zone. Institute for Coastal and Marine Resources, Technical
Report No. 4.
Town of Oak Island, 2009. CAMA Land Use Plan Update. Adopted by the Oak Island Town Council
13 April 2010.
U.S. Army Corps of Engineers Wilmington District. 2010. Archaeological and Hardbottom Surveys
of Offshore Borrow Areas with Jay Bird and Frying Pan Shoals, Brunswick Beaches, Brunswick
County, North Carolina. 89 pages.
U.S. Fish and Wildlife Service. 2017. North Carolina Coastal Beach Sand Placement Statewide
Programmatic Biological Opinion. Website: https://www.fws.gov/raleigh/pdfs/spbo.pdf.
VERSAR, 2003. Effects of dredged material beach disposal on surf zone and nearshore fish and
benthic resources on Bald Head Island, Caswell Beach, Oak Island, and Holden Beach, North
Carolina: interim study findings. Prepared for USACE, Wilmington District, NC; -prepared by
Versar Inc, Columbia, MD, Vol I, 54 pp.
NCDCM Major Permit Application
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