6_OakIsland_21_22_Narrative

North Carolina Division of Coastal Management
Major Permit Modification #31-20

2021/2022 Oak Island Renourishment Project
Oak Island, Brunswick County, North Carolina

November 24, 2020

Proposed by:

Town of Oak Island
Brunswick County, North Carolina

Prepared for:

North Carolina Department of Environmental Quality
North Carolina 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

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Table of Contents
1.0 INTRODUCTION ................................................................................................................................. 1
1.1 Background ................................................................................................................................... 1
1.2 Purpose and Need ......................................................................................................................... 4
2.0 DECRIPTION OF THE PROPOSED ACTION .......................................................................................... 5
2.1 Project Description ........................................................................................................................ 5
2.2 Methods of Construction ............................................................................................................ 26
2.3 Sediment Compatibility............................................................................................................... 30
2.3.1 Native Beach Sediment ....................................................................................................... 30
2.3.2 Proposed Borrow Area Sediment ....................................................................................... 32
2.4 Jay Bird Shoals Borrow Area Modeling ....................................................................................... 45
2.5 Survey Data Collection ................................................................................................................ 47
3.0 CULTURAL RESOURCES ................................................................................................................... 50
4.0 PROPOSED CONSERVATION MEASURES ......................................................................................... 51
5.0 COMPLIANCE WITH BRUNSWICK COUNTY AND CAMA LAND USE PLAN ....................................... 56
6.0 COMPLIANCE WITH THE NC ENVIRONMENTAL POLICY ACT .......................................................... 56
7.0 CONSTRUCTION EASEMENTS .......................................................................................................... 56
8.0 COMPLIANCE WITH DWR WATER QUALITY CERTIFICATION .......................................................... 56
9.0 REFERENCES .................................................................................................................................... 57

APPENDIX A – Permit Drawings
APPENDIX B1 – Sediment Compatibility Analysis & Vibracore Logs for Jay Bird Shoals
APPENDIX B2 – Sediment Compatibility Analysis & Vibracore Logs for Central Reach
APPENDIX C – Oak Island Geophysical Survey
APPENDIX D1 -D4 – Jay Bird Shoals Borrow Area Modeling
APPENDIX E – Central Reach Archaeological Assessment
APPENDIX F – Eastern Channel Shorebird Monitoring Report
APPENDIX G – Post-Construction Monitoring Procedure
APPENDIX H – Letter of Intent to Obtain Perpetual Easements
APPENDIX I – Scoping Meeting Summary
APPENDIX J – Supplemental Profiles

ATTACHMENT 1 NCDCM MP – 1 Application
ATTACHMENT 2 NCDCM MP – 2 Excavation and Fill

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LIST OF FIGURES
Figure 1-1. Vicinity and Location Map .......................................................................................................... 2
Figure 1-2. Summary of Oak Island Renourishment History......................................................................... 3
Figure 2-1. Project Map ................................................................................................................................ 7
Figure 2-2. Oak Island Borrow Areas ............................................................................................................ 8
Figure 2-3. Jay Bird Shoals Borrow Area Cross Sections ............................................................................. 11
Figure 2-4. Jay Bird Shoals Borrow Area Dredging Plan .............................................................................. 12
Figure 2-5. Central Reach Borrow Area Cross Sections .............................................................................. 13
Figure 2-6. Central Reach Borrow Area Dredging Plan ............................................................................... 14
Figure 2-7. Typical Construction Template Cross Sections ......................................................................... 18
Figure 2-8. IHA Station 670+00 Historical Profiles with Construction Template ........................................ 20
Figure 2-9. IHA Station 672+00 Historical Profiles with Construction Template ........................................ 21
Figure 2-10. IHA Station 674+00 Historical Profiles with Construction Template ...................................... 21
Figure 2-11. IHA Station 676+00 Historical Profiles with Construction Template ...................................... 22
Figure 2-12. IHA Station 678+00 Historical Profiles with Construction Template ...................................... 22
Figure 2-13. Representative Equilibrated Construction Template for Stations 210+00 – 230+00 ............. 24
Figure 2-14. Representative Equilibrated Construction Template for Stations 510+00 – 550+00 ............. 25
Figure 2-15. Representative Equilibrated Construction Template for Stations 560+00 – 590+00 ............. 25
Figure 2-16. Representative Equilibrated Construction Template for Stations 600+00 – 630+00 ............. 26
Figure 2-17. Staging Areas .......................................................................................................................... 29
Figure 2-18. Native Sediment Sample Transects ........................................................................................ 30
Figure 2-19. Clast Survey Areas ................................................................................................................... 32
Figure 2-20. Jay Bird Shoals Borrow Area ................................................................................................... 34
Figure 2-21: Central Reach Borrow Area .................................................................................................... 39
Figure 2-22. Central Reach Borrow Area Proximity to AR-430 ................................................................... 40
Figure 2-23. Central-08 wet versus dry sample .......................................................................................... 43
Figure 2-24. After-dredge bathymetry effects on residual tidal currents over a spring neap tidal cycle .. 46
Figure 2-25. Wave induced longshore sediment transport gradients along Caswell Beach shoreline ...... 47
Figure 2-26. Sidescan Sonar Survey Coverage of the Central Reach Borrow Area ..................................... 48
Figure 2-27. Sub-bottom Grid Survey Coverage ......................................................................................... 49
Figure 2-28. 3-D View of Sub-bottom Grid ................................................................................................. 49
Figure 2-29. Multibeam Survey Coverage of the Central Reach Borrow Area ........................................... 50
Figure 4-1. Post-Construction Monitoring of Caswell Beach ...................................................................... 55

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LIST OF TABLES
Table 2-1. Proposed vs Previously Permitted Dredging Elevations .............................................................. 9
Table 2-2. Preliminary length and renourishment fill volume .................................................................... 17
Table 2-3. Recreational Beach Width Comparison ..................................................................................... 23
Table 2-4. Native Beach Characteristics and NCAC Rule Parameters ......................................................... 31
Table 2-5. Native Beach Sediment Statistics ............................................................................................... 31
Table 2-6. Jay Bird Shoals Dredge Elevations .............................................................................................. 33
Table 2-7. Jay Bird Shoals sediment characteristics of material proposed for placement on Oak Island .. 35
Table 2-8. Jay Bird Shoals sediment statistics of material proposed for placement on Oak Island ........... 35
Table 2-9. Jay Bird Shoals composite sediment characteristics of proposed beach fill compared to native
sediment ..................................................................................................................................................... 36
Table 2-10. Jay Bird Shoals composite sediment statistics of proposed beach fill compared to native
sediment ..................................................................................................................................................... 36
Table 2-11. Central Reach Dredge Elevations ............................................................................................. 38
Table 2-12. Central Reach sediment characteristics of material proposed for placement on Oak Island . 41
Table 2-13. Central Reach sediment statistics of material proposed for placement on Oak Island .......... 41
Table 2-14. Central Reach composite sediment characteristics of proposed beach fill compared to native
sediment ..................................................................................................................................................... 42
Table 2-15. Central Reach composite sediment statistics of proposed beach fill compared to native
sediment ..................................................................................................................................................... 42
Table 2-16. Template Dredging Elevations ................................................................................................. 45

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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 barrier island
(Figure 1-1 cover sheet of permit drawings provided in Appendix A).
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, within the Cape Fear River Inlet. 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 sea turtle habitat restoration project across the central portion of the island. The
material for this restoration project came from Yellow Banks, an upland borrow area. This project
unintentionally placed rocks on the beach still present today despite removal efforts by the Town.
In 2009, the USACE dredged the Lockwoods Folly River Crossing and placed material on the
western end of Oak Island’s shoreline. In 2015, the Town sponsored the Lockwoods Folly Habitat
Restoration Project, which consisted of maintenance dredging of the navigation channel within
Eastern Channel with beneficial placement of compatible material on the western end of Oak
Island. After Hurricane Matthew (October 2016), the Town initiated and completed an
emergency dune restoration project to place material from an upland borrow source along 4.4
miles of shoreline. In 2019, material from the 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. The central portion of
the island has not experienced a significant renourishment event since 2001. The Town received
federal and state permits (SAW-2018-02230, NC Coastal Area Management Act (CAMA) Major
Permit #31-20) for a renourishment project in winter 2020/2021 to place up to approximately
1.1 million cubic yards (mcy) along 21,000 ft of oceanfront shoreline between 10th Pl. W to SE
63rd St. (Stations 300+00 to 500+00). All past USACE and Town renourishment project placement
volumes and extents discussed above are shown in Figure 1-2.

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Figure 1-1. Vicinity and Location Map

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Figure 1-2. Summary of Oak Island Renourishment History

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1.2 Purpose and Need
The Town is vulnerable to significant damage from storms since the overall beach profile has
been lowered substantially, as evidenced by the landfall of Hurricane Isaias on August 3, 2020.
Essentially, there is no protective dune throughout most of the oceanfront. The Town was
recently authorized to complete an emergency sand push in September 2020 (CAMA Major
Permit #140-10) to provide immediate protection to the oceanfront. Shoreline and dune erosion
as a result of storm surge and overwash during Hurricanes Matthew (2016), Florence (2018), and
now Isaias (2020) were particularly significant along the proposed project area. In 2017/2018, as
a result of Hurricane Matthew, the Federal Emergency Management Agency (FEMA) provided
funding for construction of a temporary protection measure in the form of an ‘emergency berm’
which placed approximately 25,000 cubic yards (cy) of material in the proposed project area to
provide immediate protection to significantly damaged sections of dune until a full project could
be completed. With the passing of Florence and Michael in 2018, Dorian in 2019, and Isaias in
2020, this emergency material has served its purpose to provide immediate protection. The Town
is taking proactive measures to restore the oceanfront shoreline and dune while providing
necessary protection. The purpose of the proposed project is to provide long-term protection to
infrastructure from a 25-year return period storm event and provide additional protection at a
known ‘hotspot’ located on the West End of the island. This ‘hotspot’ coincides with the area the
USACE nourished with material from the Lockwoods Folly Inlet/AIWW crossing in 2019.
For the Town to maintain adequate cash flow, the renourishment of the entire oceanfront is
being completed in separate projects. This proposed 2021/2022 Renourishment Project is the
second planned over the next 3-5 years (2020 and beyond). The first project, the 2020/2021
renourishment project, was authorized under CAMA Major Permit #31-20, this second
2021/2022 Renourishment Project is to be covered under a major modification to that permit.
The Town has been actively coordinating with both FEMA and the NC Department of
Environmental Quality (NCDEQ) to secure funding to mitigate for the extensive erosion
experienced from these hurricanes. The project planned for the winter of 2021/2022 will be
constructed using Post-Florence federal and state funding, as well as local funding. The project
which is currently planned for winter 2022/2023 (or later depending on Town cash flow) will be
considered the initial project for the Town’s Master Beach Renourishment Plan. The focus for the
initial Master Plan project will be replacing any dune volume lost in the interim, as well as
providing advance fill for additional storm protection in the form of a recreational berm in front
of the dune across the island. In addition, the advance fill will serve as the buffer to maintain the
profile needed for the 25-year return period storm event protection over an expected 6-yr
renourishment interval.

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The proposed 2021/2022 project features a dune designed to withstand a 25-year return period
storm event as well as a sloped berm at a 20H:1V. In addition to the dune, some areas of the
beach have a template that incorporates a berm at elevation 7.0 ft North American Vertical
Datum 1988 (NAVD88) with a width that ranges from 15 – 55 ft. Due to increased erosion
experienced at the West End ‘hotspot’, a 120 ft wide berm has been added to the dune template
in this area to help mitigate the increased erosion. In areas where the existing dune already meets
protection for a 25-year return period storm event, the template consists of only a berm width
of 70 ft to meet the minimum construction fill requirements of 15 cubic yards of material per
linear foot of shoreline (cy/ft). The template design varies across the oceanfront due to offshore
bathymetry tie ins, existing dune conditions, and minimum fill requirements based on
construction feasibility and equipment. However, all template designs provide the 25-year return
period storm event protection.
The proposed 2021/2022 project involves dredging approximately 1.667 mcy of beach-quality
sand from a combination of Jay Bird Shoals and Central Reach borrow areas.
The need for the proposed 2021/2022 Renourishment Project is to protect and preserve a large
portion of the Town’s infrastructure, tourism industry, tax base, and enhance recreational beach
access for the public.
During the proposed 2021/2022 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.
2.0 DECRIPTION OF THE PROPOSED ACTION
2.1 Project Description
Borrow Areas
The proposed 2021/2022 project consists of excavating approximately 1.667 mcy (includes
assumed 30% dredge losses) of beach-quality sediment from a combination of Jay Bird Shoals
and Central Reach borrow areas. Given the borrow area cut elevations in Jay Bird Shoals there is
sufficient beach compatible material available to allow for all the 1.667 mcy to be taken from this
borrow area, if necessary. However, up to 615,000 cy of beach compatible material is available
to be excavated from the Central Reach borrow area. The use of two borrow areas will provide

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the contractor with flexibility in constructing the project in a cost-effective manner, due to the
distance of the Jay Bird Shoals borrow area from the west end of Oak Island.
The Jay Bird Shoals borrow area is situated a distance of approximately one mile offshore of the
Oak Island/Caswell Beach shoreline (Figure 2-1). This will be the second dredging event to utilize
material from this Jay Bird Shoals borrow area, the first dredging event being the permitted
2020/2021 Renourishment Project. Other 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 1.8 miles and the farthest sail
distance from the borrow area to the placement area is about 10.9 miles. The proposed borrow
area within Jay Bird Shoals is approximately 304 acres, the same footprint permitted for the
2020/2021 project.
The Central Reach borrow area is situated a distance of approximately 1.9 miles offshore of the
Oak Island shoreline (Figure 2-1). Portions of the Central Reach borrow area have been included
in a previous renourishment event for the Town of Holden Beach (Figure 2-2). The closest sail
distance from the borrow area to the placement area is about 1.9 miles and the farthest sail
distance from the borrow area to the placement area is about 4 miles. This borrow area would
be utilized to provide a cost-effective sand source for portions of the western project placement
extent. The proposed borrow area is approximately 180 acres.

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Figure 2-1. Project Map

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Figure 2-2. Oak Island Borrow Areas

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Using vibracore data collected in 2019 (1,000 ft spacing), three different zones and cut elevations
(with 2 ft of overdredge allowance) within the Jay Bird Shoals borrow area have been identified.
Since this is an ebb shoal environment, these three varying cut elevations are intended to
maintain the integrity of the shoal and minimize the effect on the nearshore wave environment
and adjoining Caswell Beach oceanfront shoreline. The borrow area cross sections are shown in
Figure 2-3. Wave modeling was performed to quantify potential effects along the Bald Head
Island, Fort Caswell, Caswell Beach, and Oak Island oceanfront (see Section 2.4). An area of
approximately 304 acres within the outer edge of Jay Bird Shoals (Figure 2-4) has been identified
to contain approximately 4.67 mcy of beach compatible material. The footprint of the Jay Bird
Shoals borrow area is the same as was previously permitted, but the proposed elevations in
NAVD88 for this permit modification are deeper as shown in Table 2-1.
Table 2-1. Proposed vs Previously Permitted Dredging Elevations
Zone Proposed Elevation
(ft-NAVD88)
Previously
Permitted Elevation
(ft-NAVD88)
1 -28.0 -26.0
2 -37.0 -31.0
3 -29.0 -27.0
While the proposed template theoretically contains 4.67 mcy of beach compatible material, this
volume is significantly reduced due to several factors, such as:
• The 1.1 mcy that will be removed to complete the 2020/2021 Renourishment Project.
• The level of control/accuracy in the dredging process due to the unstable working
environment (waves).
• To avoid a permit violation, the contractor will naturally leave a buffer between the target
dredging elevation and the permitted elevation; this can be as much as 2-3 ft.
• The contractor will typically try to avoid areas that were previously dredged that do not
have enough material remaining above the permitted elevation. These areas are both
inefficient to dredge and pose a much higher risk of dredging below the permitted
elevation. Thus, some of the previously dredged areas utilized during the 2020/2021
Renourishment Project may not be used or will be deemed too risky to use by the
contractor.
• There are shallower areas within the proposed borrow area where a hopper dredge may
not be able to operate for safety reasons (i.e. draft of vessel is deeper than ocean floor).

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If a hopper dredge is the only available and reasonable equipment to be used by a
contractor then shallower areas of the borrow area will not be used.
• The proposed project has operating requirements for a hopper dredge stating that the
dragheads must stay on the bottom for sea turtle protection. This operating constraint is
challenging to borrow areas if there is not a sufficient buffer of material below the
contractor’s target dredging elevation and the permitted elevation. The contractor will
typically avoid areas that do not have a sufficient buffer.
• Marine debris has been identified in Zone 2 and 3. The contractor will most likely avoid
the debris by applying their own elected safe buffer distance for their dredging operations
to avoid removing the debris. This will reduce the volume available unless it is determined
that this debris can safely be removed by the contractor.
After accounting for the 1.1 mcy removed during the 2020/2021 Renourishment project and the
2 ft overdredge allowance volume (buffer for dredging inaccuracies, not to provide additional
volume), approximately 2.59 mcy will be available in the Jay Bird Shoals borrow area to meet the
need for the approximate 1.667 mcy dredge quantity for the 2021/2022 Renourishment Project.
Using vibracore data collected in 2019 (1,000 ft spacing), four different zones with unique cut
elevations (with 2 ft of overdredge allowance) within the Central Reach borrow area have been
identified. The borrow area cross sections are shown in Figure 2-5. The Central Reach borrow
area consists of approximately 180 acres (Figure 2-6) of which 1.18 mcy of beach compatible
material has been identified. After accounting for the 2 ft overdredge allowance volume (buffer
for dredging inaccuracies, not to provide additional volume), approximately 615,000 cy will be
available to meet the need for the approximately 1.667 mcy dredge quantity for the 2021/2022
Renourishment Project. The Central Reach borrow area is meant to provide a cost-effective
borrow area for material needed for portions of the west end of the project.
Detailed sediment characteristics and vibracore logs for the borrow areas are provided in
Appendix B1 and B2. Material placed on the beach will be consistent with the NC Coastal
Resources Commission (CRC) sediment compatibility standards. Placed material will be visually
monitored for sediment quality daily (via visual inspection) and weekly (via sediment analysis).
Weekly reports will be provided to the agencies.

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Figure 2-3. Jay Bird Shoals Borrow Area Cross Sections

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Figure 2-4. Jay Bird Shoals Borrow Area Dredging Plan

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Figure 2-5. Central Reach Borrow Area Cross Sections

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Figure 2-6. Central Reach Borrow Area Dredging Plan

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Construction Templates
The renourishment placement area is approximately 26,100 ft (~5 miles) along Oak Island, refer
to Appendix A for the complete set of permit drawings. Based on the bids received for the
2020/2021 Renourishment Project, the 2021/2022 Renourishment Project will also likely include
placement over 4,300 linear feet, approximately Stations 460+00 – 503+00, of the area permitted
under the 2020/2021 Renourishment Project (Figure 2-1). The material placed under either
project will not exceed the authorized volumes and permit extents. Sediment will be spread via
land-based equipment and shaped into a dune. The beach fill will involve approximately 197
acres of beach and inshore area. The main fill portions of the project will contain an average of
50 cy/ft. On average, the proposed project construction templates will move mean high water
(MHW) seaward approximately 93 feet.
There are some variations in the construction template across the island, some areas with dune
only (Stations 501+00 – 620+00), some areas with berm only (Stations 235+00 – 275+00), and
some areas with a combination of dune and berm (Stations 210+00 – 235+00 , 275+00 – 295+71,
and 620+00 – 676+36). These variations are a result of working with existing conditions to meet
the 25-year return period storm event protection. The dune crest elevation varies between 13.0
ft and 15.5 ft NAVD88 across the project; the dune crest width is consistently 10 ft. The original
design of the front and back dune slopes of 5H:1V have been a topic of discussion between
Moffatt & Nichol, NC Division of Coastal Management (NCDCM), USACE, US Fish and Wildlife
Service (USFWS), and NC Wildlife Resources Commission (NCWRC). The original dune slopes were
5H:1V to allow for public safety and access at dune walkover locations. A concern was raised
about the lack of steepness of the original design of the front dune slope as it pertains to a sea
turtle’s ability to climb up the dune and nest behind, increasing the risk of the adult turtle or
hatchlings becoming trapped behind the dune. The final design of the front dune slope was
adjusted to 4H:1V to alleviate concerns for nesting sea turtles while maintaining the back dune
slope at 5H:1V for ease of human walkover (the Town does not have structural dune walkovers).
It is expected that the front slope of the dune will steepen quickly during winter wave conditions
to a 3H:1V. This slope is close to the angle of repose for loose clean sand and is close to the
steepest slope that could be feasibly constructed.
The front dune toe will transition at elevation 7.0 ft NAVD88 and then continue out with a 20H:1V
slope until it ties into the existing profile between elevation -1.0 ft and -10.0 ft NAVD88. Some
locations will have a berm at elevation 7.0 ft NAVD88 and then continue out with a 20H:1V slope
until it ties into the existing profile. The foreshore slope was chosen to best replicate the natural
slope of the beach in efforts to mitigate significant profile equilibration directly after placement;

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however, mild equilibration of the profile is still expected and will be monitored as required by
the NC Statewide Programmatic Biological Opinion.
In the eastern most portion of the beach fill between Stations 210+00 – 235+00, the construction
template consists of both a dune and a berm. The dune elevation is 15.0 ft NAVD88. The berm
elevation is at 7.0 ft NAVD88 with a width of 15 ft. The berm is included in the template to help
meet a minimum beach fill of 15 cy/ft to ensure constructability for the contractor.
Between Stations 235+00 – 275+00 the construction template consists only of a berm at
elevation 7.0 ft NAVD88, the berm width is 70 ft. The berm width was determined to meet a
minimum beach fill of 15 cy/ft to ensure constructability for the contractor. In this area a dune is
not included in the construction template since the existing dunes provide enough protection for
the 25-year return period store event.
Between Stations 275+00 – 295+71 the construction template consists of both a dune and a
berm. The dune elevation is 14.5 ft NAVD88. The berm elevation is at 7.0 ft NAVD88 with a width
of 55 ft. The berm width was determined to meet a minimum beach fill of 15 cy/ft to ensure
constructability to the contractor. Station 295+71 marks the end of the project on the eastern
portion and where it will tie into the previous 2020/2021 Renourishment Project.
The western portion of the beach fill starts at Station 501+00 which is where the previous
2020/2021 Renourishment Project is permitted to end. Between Stations 501+00 – 620+00 the
construction template consists only of a dune. The dune elevation varies from 13.0 ft to 14.0 ft
NAVD88. The dune will break at elevation 7.0 ft NAVD88 and then continue out with a 20H:1V
slope until it ties into the existing profile.
On the west end of the island in the ‘hotspot’ area covering Stations 620+00 – 676+36 the
construction template consists of both a dune and a berm. The dune elevation varies from 13.0
ft to 15.5 ft NAVD88. The berm elevation is at 7.0 ft NAVD88 with a width of 120 ft. The berm
width in this area was determined based on the quantity of beach compatible material available
in the Central Reach borrow area as well as expected erosion rates. Station 676+36 marks the
western end of the project.
All the above described construction templates have been designed to withstand a 25-year return
period storm event. Typical construction template cross sections are shown in Figure 2-7. Filling
the construction template described above will require approximately 1.282 mcy of sand to be
placed within the project area.

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Taper sections which are approximately 500 ft long will tie the template fill into the natural
shoreline at the ends of the project. The dune will be planted with native sea oats and bitter
panicum; to be installed on 18” centers. A summary of the renourishment placement and fill is
shown in Table 2-2.
Table 2-2. Preliminary length and renourishment fill volume
Renourishment
Reach
1Reach
Length (ft)
Project
Station
Approximate
Geographic
Location
Average Unit
Fill Volume
(cy/ft)
Reach
Volume
(cy)
Oak Island East
End 8,600 210+00 to
300+00
McGlamery St. to
SE 63rd St. 23 195,500
Oak Island
West 12,000 500+00 to
620+00
7th Place West to
51st Place W 35 411,000
Oak Island
West End 5,500 620+00 to
680+00
51st Place W to The
Point 120 675,500
1Reach length includes 500-ft taper section at the beginning and end of reach.

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Figure 2-7. Typical Construction Template Cross Sections

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The existing ground survey used to develop the 2021/2022 Renourishment Project construction
template was collected three days after Hurricane Isaias hit Oak Island. The existing ground
survey demonstrates a severely eroded beach before any recovery, natural or otherwise (i.e.
emergency dune pushing or placement of overwash sand), could take place. It is understood that
conditions of the beach will change from what is being shown on plans by the time construction
is anticipated to take place (winter 2021/2022). However, since the plans are based on this
severely eroded state (worst case scenario) it is expected some recovery will occur prior to
construction. This recovery could change what is shown on plans by shifting the landward
construction template tie in seaward (out from underneath or right in front of homes) and
possibly reduce the seaward movement of MHW or vice-versa depending on the state of the
beach at the time of construction.
In addition, some portions of the construction template on the west end (Station 647+00 –
659+50, 665+50 – 676+36) include a level landward tie in at elevation 7.0 ft NAVD88 behind the
dune, which will be vegetated. This is to prevent the creation of a trench behind the dune and
avoid potential turtle hatchling entrapment in the event a nest ends up behind the dune. By the
time the project is constructed, it is expected that some recovery will have taken place to
eliminate the need for this design feature, however it is being shown based on the Post-Isaias
survey used to design plans.
Of further note, surveys are collected on profile lines spaced approximately 1,000 ft apart,
meaning that the survey in between these 1,000 ft spaced profiles is interpolated. This
interpolation over 1,000 ft creates some inaccuracy from actual conditions. These inaccuracies
are corrected in the field before and during construction when more closely spaced surveys (100
ft) are obtained.
As described previously, the Town has been impacted by several hurricanes, including Matthew
(2016), Florence (2018), Dorian (2019), and Isaias (2020) and has been unable to complete a
large-scale renourishment project to restore beach conditions. As a result, there has been
substantial loss of recreational berm, dune, and native dune vegetation across the oceanfront.
As requested during the project scoping meeting, the construction template is overlain on the
2020 Post-Isaias aerial image (Appendix A) with the digitized 2016 vegetation line displayed for
reference. NCDCM has proposed to the CRC to designate Unvegetated Beach Areas of
Environmental Concern (AEC) for two areas of the shoreline. Both of the proposed areas, from
approximately Station 430+00 to 550+00 and Station 660+00 to 674+00, are within the limits of
the 2021/2022 Renourishment Project. With the absence of any existing vegetation it may be
desirable to move the dune alignment further landward. However, doing that also moves MHW
closer to structures and affects the vegetation line setback used for development purposes. The

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location and alignment of the construction template is based on historical profiles and
construction feasibility. It is important to the Town to maintain a historic dune and vegetation
alignment which existed prior to Hurricane Matthew (2016). The design intent is to provide the
shoreline with protection from future storms and ensure that this level of protection is
continually maintained as part of the Master Plan.
Inlet Hazard Area
A portion of the Inlet Hazard Area (IHA) coincides with the western end of the project from
Station 667+65 – 675+65, which corresponds with monitoring Stations 670+00 – 678+00. As
noted in the Specific Use Standards for Ocean Hazard Areas, 15A NCAC 7H.0308(b)(5), within the
IHA “no new dunes shall be created”. The final design location of the dune within the IHA
underwent several iterations, in collaboration with NCDCM, to adhere to the guidance. The
monitoring station profiles shown in Figure 2-8 through Figure 2-12 display the available
historical survey for the profiles within the IHA and how the construction template intends to
restore the previously existing dune. The 200-ft spaced stations only have historical survey dating
back to 2018. The structure locations shown are representative, as the profile applies to adjacent
areas, and may not line up exactly with their physical location.

Figure 2-8. IHA Station 670+00 Historical Profiles with Construction Template

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Figure 2-9. IHA Station 672+00 Historical Profiles with Construction Template

Figure 2-10. IHA Station 674+00 Historical Profiles with Construction Template

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Figure 2-11. IHA Station 676+00 Historical Profiles with Construction Template

Figure 2-12. IHA Station 678+00 Historical Profiles with Construction Template

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Construction Templates Equilibration
To quantify the equilibration, or profile adjustment over the first 12 months (Willson, et al. 2017),
the construction template at four representative locations within the project area were chosen.
The SBEACH model was used to produce an output profile from the 2-yr storm which was used
as an assumption of the resulting equilibrated construction template. Oak Island has over 9 miles
of oceanfront containing 60 monitoring profiles. SBEACH modeling of the renourishment
equilibration is not feasible at every location within the project limits, which is why
representative locations were chosen. Station 220+00 was chosen to represent from 210+00
through 230+00, Station 540+00 was chosen to represent from 510+00 through 550+00, Station
570+00 was chosen to represent from 560+00 through 590+00, and Station 600+00 was chosen
to represent from 600+00 through 630+00. These stations were carefully chosen to best
represent the given reach. This analysis was only performed at the representative locations
within the project where there was a concern that the recreational beach width would be
negatively impacted during equilibration; therefore, construction templates consisting of a dune
and berm (greater than 15ft wide) combination or berm only were not analyzed. The recreational
beach width is assumed to be the horizonal distance between elevation 7.0 ft NAVD88 (berm)
and 1.8 ft NAVD88 (MHW). The recreational beach width for the Pre-Matthew profiles was
averaged over the profiles within a given reach and compared to the representative equilibrated
beach fill template. The results are shown in Table 2-3. Within each reach, the recreational beach
width after equilibration is wider than the Pre-Matthew recreational beach width; therefore, the
equilibrated construction template will not negatively impact the recreational beach width when
compared to the 2016 (Pre-Matthew) conditions when a dune was present within the project
area.
Table 2-3. Recreational Beach Width Comparison
Reach
Average 2016 Pre-
Matthew Recreational
Beach Width (ft)
Representative 21/22 Post Fill
Equilibration Recreational
Beach Width (ft)
210+00 - 230+00
(Rep Profile: 220+00) 69 86
510+00 - 550+00
(Rep Profile: 540+00) 61 73
560+00 - 590+00
(Rep Profile: 570+00) 60 82
600+00 - 630+00
(Rep Profile: 600+00) 57 96

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Equilibration results from SBEACH are shown in Figure 2-13 through Figure 2-16, the
preconstruction profiles shown in the figure are from the June 2019 survey. The model indicates
that material placed in the dune and sloped berm will be transported to the offshore bar. Mild
equilibration of the dune profile is also expected; however, this will act as a sand source for the
sloped berm over time.

Figure 2-13. Representative Equilibrated Construction Template for Stations 210+00 – 230+00
MHW

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Figure 2-14. Representative Equilibrated Construction Template for Stations 510+00 – 550+00

Figure 2-15. Representative Equilibrated Construction Template for Stations 560+00 – 590+00
MHW
MHW

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Figure 2-16. Representative Equilibrated Construction Template for Stations 600+00 – 630+00
2.2 Methods of Construction
The proposed project would involve the use of either a hopper dredge or a cutter suction
(hydraulic) dredge to excavate sand from Jay Bird Shoals borrow area and the Central Reach
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
MHW

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which is typically an anchored floating structure, buoy, or multiple buoy berths. The nearshore
pump-out station will be situated in 25-35 ft 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.
Cutter suction dredges are stationary dredges that are moored at the borrow area 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 ft 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 area 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 elevation; the CSD will take all available material to the desired elevation 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

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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. Equipment can be stored at staging areas shown on Figure 2-17. 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 following project completion. Daily
equipment staging will be on the constructed beach seaward of the dune line. Construction
contracts will provide for proper 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(s) 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. The majority of existing public access to the beach will
remain open at all times during construction, except for a few that may be used for staging/access
areas, again see Figure 2-17. Offshore pump-out stations and appurtenances would not affect
commercial or recreational boating.
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. It is anticipated the proposed
construction will be accomplished in approximately three to four months, unless multiple
dredges are deployed on the project which would shorten the construction period. All beach fill
construction activities would take place within the 16 November through 30 April environmental
window.

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Figure 2-17. Staging Areas

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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 with borrow areas. 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 defined transect as
specified in NC Administrative Code 15A NCAC 07H.0312(1). These 13 samples were than
averaged to obtain a composite average for the transect. Eleven transects were sampled along
the shoreline of Oak Island (Figure 2-18) with efforts to maintain required spacing while also
avoiding recent renourishment projects.

Figure 2-18. Native Sediment Sample Transects

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The composite average for each of the 11 transects were then averaged to obtain a global mean
for the native beach. The composite average from all 11 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. A summary of the characteristics for the native beach is provided in Table 2-4. The
table also demonstrates the acceptable grain size criteria for beach placement in accordance with
15A NCAC 07H.0312(3), which establishes consistent standards for native grain size for all future
projects. 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 0.26
millimeter (mm). The native beach is coarse skewed and moderately sorted, as indicated by the
native beach sediment statistics presented in Table 2-5.

Table 2-4. 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 2-5. Native Beach Sediment Statistics
Sediment
Compatibility
2019 Native
Global Mean
Median (mm) 0.26
Median (φ) 1.97
Mean (mm) 0.27
Mean (φ) 1.90
Standard
Deviation (σφ) 0.81

Moffatt & Nichol conducted field investigations on October 28, 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 in 15A NCAC 07H.0312(4)(c). The investigation was performed
in the area shown in Figure 2-19 between Stations 460+00 and 470+00. This area had received

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nourishment in the spring of 2018. Results of the investigation found 58 pieces of shell material
greater than or equal to three inches in diameter.

Figure 2-19. Clast Survey Areas
2.3.2 Proposed Borrow Area Sediment
JAY BIRD SHOALS BORROW AREA
Vibracores in the Jay Bird Shoals borrow area were obtained by American Vibracore Services
(AVS) in February and March of 2019. Figure 2-20 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 (see Appendix C), volume calculations indicate
approximately 3.69 mcy of material exists in the three (3) zones within the Jay Bird Shoals borrow
area when excluding the 2 ft of overdredge allowance material. It is assumed that the first project
in 2020/2021 will remove approximately 1.1 mcy from the borrow area, which would leave 2.59
mcy in the borrow area for the project in 2021/2022. The 2021/2022 Renourishment Project has
an expected total dredge volume of 1.667 mcy. Therefore, the material within the Jay Bird Shoals
borrow area will be enough to fully cover the dredge volume for the 2021/2022 project if the
contractor chooses.
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, see Table
2-6. The average cut depth, not including overdredge, across Zone 1 is 5.8 ft, Zone 2 is 9.8 ft, and
Zone 3 is 6.9 ft. Since this is a shoal environment, these cut depths are intended to maintain the
integrity of the shoal by not allowing waves to break closer to shore and cause unintended effects
on the adjacent shoreline. A comprehensive modeling report for the Jay Bird Shoals borrow area
is provided in Appendix D and a summary of the modeling is discussed in Section 2.4.

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Table 2-6. Jay Bird Shoals Dredge Elevations
Zone Deepest Compatible Material
Elevation (ft, NAVD88)
Design
Elevation (ft,
NAVD88)
+2 ft Overdredge
Allowance (ft,
NAVD88)
1 Varies between -32 and -40.5 -26.0 -28.0
2 Varies between -39.5 and -41.5 -35.0 -37.0
3 Varies between -33 and -38 -27.0 -29.0

Sediment characteristics and statistics are presented in Table 2-7 and Table 2-8. As noted, the
sediment characteristics and statistics presented consider a composite average down to the
design elevation for each zone.
Appendix B1 provides a summary 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 B1 will be different than the composite averages shown
in Table 2-7 and Table 2-8. Appendix B1 shows the composite average for the entire vibracore
sample, while Table 2-7 and Table 2-8 show the composite average for the vibracore down to
the design elevation (with overdredge) for each zone. The borrow area vibracores meet all the
grain size criteria for beach placement as established in 15A NCAC 07H.0312 (Table 2-9). The
typical sediment type in Jay Bird Shoals is medium-grained sand (mean size = 0.34 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 2-10).

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Figure 2-20. Jay Bird Shoals Borrow Area

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Table 2-7. Jay Bird Shoals sediment characteristics of material proposed for placement on Oak Island
Sediment
Compatibility
Zone 1 Dredge Elevation -26 ft NAVD88
(+2 ft overdredge -28 ft NAVD88)
Zone 2 Dredge Elevation -35 ft NAVD88
(+2 ft overdredge -37 ft NAVD88)
Zone 3 Dredge Elevation -27 ft NAVD88
(+2 ft overdredge -29 ft NAVD88)
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 1.92% 1.24% 1.33% 0.17% 1.60% 1.85% 0.77% 1.20% 2.89% 0.74% 2.94% 1.37% 3.67%
Granular 4.40% 2.30% 2.72% 0.90% 2.78% 3.14% 1.73% 5.47% 6.43% 3.55% 6.82% 3.20% 5.02%
Sand 88.61% 92.30% 91.18% 96.52% 91.36% 88.79% 93.03% 89.09% 84.26% 91.72% 85.66% 90.97% 86.41%
Fines 5.07% 4.16% 4.77% 2.41% 4.26% 6.22% 4.46% 4.23% 6.43% 3.99% 4.58% 4.46% 4.90%
Carbonate 15.34% 18.42% 11.08% 10.32% 14.24% 13.29% 11.49% 24.06% 10.24% 10.11% 18.43% 9.95% 16.85%
Median (mm) 0.23 0.29 0.26 0.24 0.28 0.29 0.25 0.29 0.26 0.29 0.26 0.22 0.29
Mean (mm) 0.32 0.33 0.32 0.27 0.34 0.37 0.28 0.36 0.38 0.34 0.37 0.29 0.41
Note: characteristics represent the composite average down to specified zone dredge elevation with overdredge.
Table 2-8. Jay Bird Shoals sediment statistics of material proposed for placement on Oak Island
Sediment
Compatibility
Zone 1 Dredge Elevation -26 ft NAVD88
(+2 ft overdredge -28 ft NAVD88)
Zone 2 Dredge Elevation -35 ft NAVD88
(+2 ft overdredge -37 ft NAVD88)
Zone 3 Dredge Elevation -27 ft NAVD88
(+2 ft overdredge -29 ft NAVD88)
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 0.26 0.24 0.28 0.29 0.25 0.29 0.26 0.29 0.26 0.22 0.29
Median (φ) 2.14 1.78 1.94 2.07 1.85 1.77 1.99 1.80 1.96 1.80 1.93 2.21 1.77
Mean (mm) 0.32 0.33 0.32 0.27 0.34 0.37 0.28 0.36 0.38 0.34 0.37 0.29 0.41
Mean (φ) 1.65 1.58 1.64 1.90 1.57 1.42 1.82 1.46 1.38 1.54 1.43 1.77 1.28
Standard
Deviation (σφ) 1.55 1.34 1.30 0.91 1.25 1.52 0.91 1.30 1.77 1.37 1.69 1.49 1.67
Note: statistics represent the composite average down to specified zone dredge elevation with overdredge.

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Table 2-9. Jay Bird Shoals 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% 1.59%
Granular 0.71% ≤ 11% 3.57%
Sand 96.96% - 90.23%
Fines 1.88% ≤ 7% 4.61%
Carbonate 9.72% ≤ 25% 13.98%
Median (mm) 0.26 - 0.27
Mean (mm) 0.27 - 0.34
Note: characteristics for Jay Bird Shoals composite average down to specified zone dredge elevations
with overdredge.
Table 2-10. Jay Bird Shoals composite sediment statistics of proposed beach fill compared to native
sediment
Sediment
Compatibility
2019 Native
Global Mean
Jay Bird Shoals
Composite
Median (mm) 0.26 0.27
Median (φ) 1.97 1.90
Mean (mm) 0.27 0.34
Mean (φ) 1.90 1.56
Standard
Deviation (σφ) 0.81 1.39
Note: statistics for Jay Bird Shoals composite average down to specified zone dredge elevations with
overdredge.
Munsell Color
Although no documented State or Federal criteria for sediment color exist, the USFWS has
recommended that to minimize effects on sea turtles the wet Munsell color of sediment samples
must 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 B1 there are two colors noted for the vibracore samples. One color was recorded
while the sample was still wet by AVS staff (March 2019). The other color was recorded by
Moffatt & Nichol staff after the sample had been exposed to the sun and allowed to dry for a
month (August 2019).

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Comments received by USFWS, dated November 21, 2019, to the USACE on the use of Jay Bird
Shoals for the 2020/2021 project noted some concerns on color as detailed in the following
quote. “The wet Munsell color of some of the core samples are quite dark (values of 3 or 4). Wet
Munsell color of the borrow material should be similar to the native beach material, and should
typically have a value greater than 5 (regardless of the hue or chroma). It may be that as material
is mixed during sand placement, the color value of the material will be sufficiently light,
…However, it will be important for the applicant to ensure that the material is suitable prior to
placement on the beach.” No additional color testing of the Jay Bird Shoals vibracores was
requested by the agencies.

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CENTRAL REACH BORROW AREA
Vibracores in the Central Reach borrow area were obtained by AVS in February and March of
2019. In total, 81 vibracores were analyzed with respect to the NC Technical Standards for
sediment parameters. These vibracores were grouped based on compatibility and combined into
zones. Figure 2-21 gives the location of vibracores and the bathymetry of the proposed borrow
area within Central Reach.
Artificial reef (AR-430) or fish haven as denoted on the navigation chart near the Central Reach
borrow area is approximately 85 ft outside of the 2,000 ft buffer as shown in Figure 2-22. No
impact to AR-430 is expected from dredging operations within the Central Reach borrow area.
Using a multibeam bathymetric survey collected by Geodynamics in 2019 (see Appendix C),
volume calculations indicate approximately 615,000 cy of material exists in the four (4) zones
within the Central Reach borrow area when excluding the 2 ft of overdredge allowance material.
If the contractor chooses, they will have the authorization to excavate 615,000 cy of material
from Central Reach to help meet the need for the approximate 1.667 mcy dredge volume for the
2021/2022 Renourishment Project.
The borrow area was divided into four (4) zones as beach compatible material exists down to
varying elevations, see Table 2-11. The average cut depth, not including overdredge, across Zone
1 is 1.7 ft, Zone 2 is 3.0 ft, Zone 3 is 0.5 ft, and Zone 4 is 2.3 ft. The sediment characteristics and
statistics for the Central Reach borrow area material are presented in Table 2-12 and Table 2-13.
As noted, the sediment characteristics and statistics presented consider a composite average
down to the design elevation for each zone.
Table 2-11. Central Reach Dredge Elevations
Zone Deepest Compatible Material
Elevation (ft, NAVD88)
Design
Elevation (ft,
NAVD88)
+2 ft Overdredge
Allowance (ft,
NAVD88)
1 Varies between -40 and -43.4 -38.0 -40.0
2 Varies between -41.7 and -49 -39.7 -41.7
3 -39.3 -37.3 -39.3
4 Varies between -42 and -46 -40.0 -42.0

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Figure 2-21: Central Reach Borrow Area
Zone Dredge Elevation
(ft, NAVD88)Volume (cy)Overdredge Elevation
(ft, NAVD88)Volume (cy)
Zone 1 -38 117,010 -40 252,039
Zone 2 -39.7 224,200 -41.7 370,470
Zone 3 -37.3 20,160 -39.3 86,536
Zone 4 -40 253,630 -42 471,774
Total 615,000 1,180,818

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Figure 2-22. Central Reach Borrow Area Proximity to AR-430

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Appendix B2 provides a summary 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 B2 will be different than the composite averages shown
in Table 2-12 and Table 2-13. Appendix B2 shows the composite average for the entire vibracore
sample, while Table 2-12 and Table 2-13 show the composite average for the vibracore down to
the design elevation (with overdredge) for each zone. The borrow area vibracores meet all grain
size criteria for beach placement as established in 15A NCAC 07H.0312 (Table 2-14). The typical
sediment type in Central Reach is medium-grained sand (mean size = 0.32 mm) that is poorly
sorted. This preliminary comparison shows the proposed borrow area sediments to be similar to
the native material (Table 2-15).
Table 2-12. Central Reach sediment characteristics of material proposed for placement on Oak Island
Sediment
compatibility

Zone 1 Dredge
Elevation -38 ft
NAVD88
(+2 ft overdredge -40
ft NAVD88)
Zone 2 Dredge
Elevation
-39.7 ft NAVD88
(+2 ft overdredge-
41.7 ft NAVD88)
Zone 3 Dredge
Elevation
-37.3 ft NAVD88
(+2 ft overdredge -
39.3 ft NAVD88)
Zone 4 Dredge Elevation -40 ft
NAVD88
(+2 ft overdredge -42 ft NAVD88)
Central-07 Central-08 Central-09 Central-10 Central-16 Central-18 Central-19 Central-20
Gravel 1.92% 3.52% 3.54% 3.60% 4.43% 2.45% 4.28% 3.66%
Granular 3.25% 3.93% 7.91% 4.88% 4.86% 4.17% 5.39% 2.81%
Sand 89.31% 86.58% 83.37% 86.96% 86.94% 88.28% 86.47% 86.66%
Fines 5.52% 5.97% 5.17% 4.55% 3.76% 5.10% 3.85% 6.87%
Carbonate 14.00% 7.82% 18.59% 10.33% 24.78% 19.48% 22.85% 14.40%
Mean (mm) 0.24 0.27 0.42 0.35 0.32 0.32 0.28 0.24
Median (mm) 0.18 0.18 0.30 0.23 0.20 0.22 0.17 0.16
Note: characteristics represent the composite average down to specified zone dredge elevation with overdredge.
Table 2-13. Central Reach sediment statistics of material proposed for placement on Oak Island
Sediment
compatibility
Zone 1 Dredge
Elevation -38 ft
NAVD88
(+2 ft overdredge -40
ft NAVD88)
Zone 2 Dredge
Elevation
-39.7 ft NAVD88
(+2 ft overdredge-
41.7 ft NAVD88)
Zone 3 Dredge
Elevation
-37.3 ft NAVD88
(+2 ft overdredge -
39.3 ft NAVD88)
Zone 4 Dredge Elevation -40 ft
NAVD88
(+2 ft overdredge -42 ft NAVD88)
Central-07 Central-08 Central-09 Central-10 Central-16 Central-18 Central-19 Central-20
Mean (mm) 0.24 0.27 0.42 0.35 0.32 0.32 0.28 0.24
Mean (φ) 2.06 1.89 1.24 1.50 1.64 1.66 1.84 2.06
Median (mm) 0.18 0.18 0.30 0.23 0.20 0.22 0.17 0.16
Median (φ) 2.46 2.46 1.72 2.13 2.35 2.19 2.54 2.67
Standard
Deviation (σφ) 1.30 1.51 1.64 1.5 1.62 1.52 1.66 1.54
Note: statistics represent the composite average down to specified zone dredge elevation with overdredge.

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Table 2-14. Central Reach composite sediment characteristics of proposed beach fill compared to native
sediment
Sediment
Compatibility
2019 Native
Global Mean
NCAC
Maximum
Central Reach
Composite
Gravel 0.45% ≤ 6% 3.40%
Granular 0.71% ≤ 11% 4.97%
Sand 96.96% - 86.53%
Fines 1.88% ≤ 7% 5.09%
Carbonate 9.72% ≤ 25% 16.17%
Median (mm) 0.26 - 0.22
Mean (mm) 0.27 - 0.32
Note: characteristics for Central Reach composite average down to specified zone dredge elevations with
overdredge.
Table 2-15. Central Reach composite sediment statistics of proposed beach fill compared to native
sediment
Sediment
Compatibility
2019 Native
Global Mean
Central Reach
Composite
Median (mm) 0.26 0.22
Median (φ) 1.97 2.22
Mean (mm) 0.27 0.32
Mean (φ) 1.9 1.65
Standard
Deviation (σφ) 0.81 1.56
Note: characteristics for Central Reach composite average down to specified zone dredge elevations with
overdredge.
Munsell Color
Although no documented State or Federal criteria for sediment color exist, the USFWS has
recommended that to minimize effects on sea turtles the wet Munsell color of sediment samples
must be at least a 5. As mentioned previously, the vibracores were collected in February and
March of 2019, after undergoing sieve analysis, the vibracores were then transferred to the Town
in July of 2019. In Appendix B2 there are two colors noted for the vibracore samples. One color
was recorded while the sample was still wet by AVS staff (March 2019). The other color was
recorded by Moffatt & Nichol staff after the sample had been exposed to the sun and allowed to
dry for a month (August 2019). All Central Reach vibracore Munsell colors recorded were gray
(10YR-5/1, 10YR-6/1). There was one vibracore (Central-10) where dry readings for some samples

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were not able to be obtained, due to the vibracore section being damaged in transit. However, it
is expected that these samples which recorded as a wet 10YR-3/1 would lighten since samples
one (1) and two (2), which also recorded as a wet 10YR-3/1, lightened to a 10YR-6/1 after being
left in the sun for a month. As the final dredging and overdredge elevations for the Central Reach
borrow area were being optimized, Moffatt & Nichol staff had to collect dry color readings for
some vibracore depths which were not considered previously. This explains the couple of
samples that have a March 2020 dry color recording noted in Appendix B2.
After receiving clarification from USFWS that the Munsell color recorded from the samples which
had been dried for a month did not meet the recommendation as they were not wet, M&N staff
took the dried samples and wetted them to then record the Munsell color. These results can be
found in Appendix B2. Wetting of the dried samples did not take place for every vibracore, as
many vibracores had similar Munsell color classifications. For example, vibracores in the same
dredge zone that had same color transitions, i.e. AVS recorded wet sample as 10YR-3/1 and MN
recorded dry sample as 10YR-6/1 were only tested on one vibracore in the zone that exhibited
this behavior. The result from the sample tested was assumed to be applied to the other
vibracore in the dredge zone with the same color classifications. Some samples once wetted, do
not meet the recommendation of at least a 5. Most of the dried samples once wetted ended up
one shade lighter, some returning back to the original wet Munsell color classified by AVS staff.
Some samples appeared to fall between two Munsell color classifications i.e. between 10YR-3/1
and 10YR-4/1. Figure 2-23 below shows a comparison of a wet and dry sample taken from the
first 6 inches of vibracore Central-08. In this figure the right sample is dry, and the color was
recorded as a 10YR-6/1; the left sample is wet, and the color was recorded as a 10YR-5/1.

Figure 2-23. Central-08 wet versus dry sample

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Two studies by the USACE have been performed to investigate sediment color changes over time
in regard to beach nourishment efforts. One study from 2013, titled “Dauphin Island Pilot Study:
Color Change of Black Warrior-Tombigbee Waterway (BWT) Sand Placed Along the Shoreline of
Eastern Dauphin Island, Alabama” found that “over the course of a year color change for river
sand placement went from a wet Munsell color predominately light yellowish brown to a light
gray and a dry Munsell color of predominately pale brown to white.” This equates to an average
Munsell value increase of 1.43 within 12 months. In this study the color changes could not be
attributed to any particular mechanism and likely resulted from a combination of mixing with
native sand, sediment transport, photochemical bleaching, oxidation, and/or alteration of iron
oxide or other sediment coatings.
The second study completed by the USACE Engineer Research and Development Center in 2018
titled ‘Investigating Sediment Color Change Dynamics to Promote Beneficial Use Applications’
focuses on “evaluating factors driving sediment color change with an emphasis on chemical
processes”. The study acknowledges that ‘Although practitioners report substantial sediment
color change after beneficial use project placement, the sediment color changes process and
associated underlying mechanisms remain poorly documented.” Further that, “Reported color
changes likely result from a combination of physical and chemical processes including abrasion,
sediment transport (e.g., winnowing of darker, fine materials), sediment mixing, removal of
sediment particle coatings, oxidation of decomposable organic matter, and photochemical
bleaching.” The study found that “Removing carbonates, organic matter, and iron oxide coatings
increased the Munsell value across all sediments examined by an average of 1.0 Munsell value.
It also found that mixing dark fine silt (Munsell value <3) with another silt (Munsell value 4.2)
resulted in Munsell value increases of 1-2 units. Finally, the study concluded that bleached
sediments experienced color rate increases of 0.3-0.5 Munsell value. Sediment color concerns
remain poorly defined but “A variety of recent (Maglio et al. 2015) and ongoing research reports
the removal of dark sediments during the dredging and beneficial placement process.”
It is important to note that vibracores from across the Central Reach borrow area will be dredged
and mixed together at same time, some vibracores having lighter color and some having darker
color. As a reminder, all the vibracores within the Central Reach Borrow Area meet the sediment
compatibility requirements as identified in 15A NCAC 07H.0312. Ultimately, the material placed
on the beach will be closely monitored for color (and other sediment characteristics) to ensure it
remains compatible and to the satisfaction of the agencies.

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2.4 Jay Bird Shoals Borrow Area Modeling
To investigate the potential effects of dredging the Jay Bird Shoals borrow area on tidal currents,
nearshore waves, and sediment transport along the adjacent shoreline, the existing model
bathymetry was modified to reflect the proposed after-dredge conditions. Dredging elevations
were increased from the borrow area template that was permitted for the 2020/2021
Renourishment Project (Template 2). These elevation increases will provide the additional
volume necessary for the proposed 2021 /2022 Renourishment Project (Template 1). The
increased dredging elevations also provide additional flexibility and efficiencies for dredge
equipment based on the bidding and construction history from the 2020/2021 project. The
footprint of the proposed borrow area is the same as was previously permitted (304 acres), but
the proposed dredge elevations for this permit modification are deeper as shown in Table 2-16.
Table 2-16. Template Dredging Elevations
Zone
Template 1
Proposed Elevation
(ft-NAVD88)
Template 2
Previously
Permitted Elevation
(ft-NAVD88)
1 -28.0 -26.0
2 -37.0 -31.0
3 -29.0 -27.0

The maximum dredging scenario was considered for both templates, i.e. assuming to remove all
the available material identified as beach compatible, 4.67 mcy for Template 1 and 2.95 mcy for
Template 2. This assumption is conservative since, as discussed earlier, the dredge will not
remove all this material. Thus, 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 the proposed Template 1 scenario, effects on
residual tidal currents would be localized and small, similar to the previously permitted Template
2 scenario. This implies there would be no significant effects on sediment transport processes
associated with tidal currents due to implementing the changes in elevations for Template 1.
Figure 2-24 shows the effects of the proposed template (Template 1) and previously permitted
template (Template 2) on residual tidal currents over a spring-neap tidal cycle.

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Figure 2-24. 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 both after-dredge bathymetry templates within Jay Bird Shoals could result
in a slight redistribution of wave energy along the Caswell Beach shoreline during moderate to
severe storm events.
Thus, sediment transport analyses were also completed, to observe if the changes to wave
heights and wave directions would affect longshore transport. The sediment transport 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. Potential effects on
shoreline erosion in other areas are minimal, although some areas may experience increased
shoreline accretion. Based on the model results of the longshore sediment transport gradients
as presented in Figure 2-25, 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 –
185+00). Generally, both templates show results close to existing conditions, with some areas
showing transport rates above and below existing conditions.

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Figure 2-25. Wave induced longshore sediment transport gradients along Caswell Beach shoreline
Considering the results, there is no strong evidence that the proposed Template 1 would cause
significant impacts in comparison with previously permitted Template 2, especially given that this
is not a morphological model. The sediment transport inside the surf zone is greatly influenced
by the imposed model bathymetry. Thus, the results only represent the bathymetric condition
constructed based on the available data sources. Therefore, Template 1 is proposed to complete
the 2021/2022 Renourishment Project. Given the dredging process inefficiencies previously
discussed, Template 1 will allow for efficient and effective use of additional beach compatible
sediment.
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
exceed 1,000 feet. Geodynamics completed a survey of the Central Reach borrow area in June
2019. Data collected included magnetometer, sidescan sonar, sub-bottom, and multibeam,
survey data collection methods and other information are detailed in Appendix C.

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As a note all survey data for the Jay Bird Shoals borrow area was provided in the 2020/2021
Renourishment Project application and is also available in Appendix C.
The results of the magnetometer data were reviewed by Tidewater Atlantic Research, Inc. to
determine the presence and proper avoidance of any cultural resources. This is discussed further
in Chapter 3.0 Cultural Resources.
The sidescan sonar mosaic data in Figure 2-26 illustrates the relative differences in bottom type
throughout the Central Reach borrow area. There are observed distinct sand ridges with a rather
homogenous bottom type. The sub-bottom data was collected on grid line spacing of 1,000 ft,
see Figure 2-27 below. Figure 2-28 shows a 3D diagram illustrating the sediment horizons from
the collected sub-bottom data. The dark orange line represents the extents of the ‘shallow’
reflector and the lime green line represents the ‘base’ reflector or deepest, continuous reflector.
The multibeam data collected, shown in Figure 2-29 below, was used to determine the total
dredge volume for the borrow area.

Figure 2-26. Sidescan Sonar Survey Coverage of the Central Reach Borrow Area

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Figure 2-27. Sub-bottom Grid Survey Coverage

Figure 2-28. 3-D View of Sub-bottom Grid

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Figure 2-29. Multibeam Survey Coverage of the Central Reach Borrow Area
3.0 CULTURAL RESOURCES
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 167 anomalies
resulting from the 2019 magnetometer and sonar survey (Appendix E). Results identified all
anomalies were generated by modern debris such as tires, chain/cable, and small objects such as
traps; of which 27 of the 167 anomalies fall within the 180-acre proposed Central Reach borrow
area. No buffers were recommended for the anomalies identified.

As a note the cultural resources investigation for the Jay Bird Shoals borrow area was provided
in the 2020/2021 Renourishment Project application.

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4.0 PROPOSED CONSERVATION MEASURES
The following conservation measures will be implemented by the Town and contractor to avoid
or minimize potential impacts on the affected environment and federally managed species and
critical habitat that may occur within the dredging and pipeline footprint, beach placement, and
staging areas. In addition to those listed below, the Town is committed to Reasonable Prudent
Measures and Terms and Conditions listed under sand placement from beach nourishment
activities in the USFWS 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 and Best Management Practices would be applied to all sand
placement and dredging activities.

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Sand Placement
• Pipelines will be equipped with spreaders to reduce effluent discharge velocities during
sand-slurry placement. As appropriate, temporary longitudinal sand dikes would be used
to contain and 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.
• All sediment and erosion control measures shall be equal to or exceed the requirements
of the NC Sediment and Erosion Control Manual.
• Construction equipment and activities will not be near the bare sand area adjacent to the
inlet where many protected avian species forage and nest. The Town conducted three
years of shorebird monitoring to analyze habitat use within the inlet complex (See
Shorebird Monitoring Report in Appendix F).

Dredging
• A hydrographic survey covering the entire area where the dredge is expected to operate
will be conducted before and after the dredging event.
• The contractor will be required to comply with requirements stated in the 2020 South
Atlantic Regional Biological Opinion (SARBO 2020).
• Operation and Dredging Endangered Species System (ODESS) – the dredge should be
equipped with a tablet running ODESS software to track and document the presence of
sea turtle, sturgeon, and marine mammal species during dredge operations. The system
must be connected to the internet and be a stand-alone system, as well as have the USACE
ODESS data collection and reporting software (ODESS Field Collector Tool).
• 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 NC Technical Standards for Beach Fill Projects (15A NCAC
07H.0312). Monitoring of fill material at the pipeline outfall will be conducted daily by the
contractor 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 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.

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• Should dredging operations encounter incompatible sand, the dredge operator will cease
operations immediately and contact NCDCM.

Post-Construction Monitoring
• The NCDCM and USACE hosted a meeting in January 2020 to discuss the 2020/2021
Renourishment Project with neighboring stakeholders (Caswell Beach and the Village of
Bald Head Island) in which a monitoring plan was discussed associated with use of the Jay
Bird Shoals borrow area. As agreed by all parties, the Town will monitor the Caswell Beach
shoreline annually for three (3) years post-construction to investigate any potential
shoreline change effects. Further details on the post-construction monitoring procedure
can be found in Appendix G. Figure 4-1 below shows the extents of the proposed
monitoring. For comparison, it also shows the extents of Bald Head Island’s current
monitoring efforts on Caswell Beach.
• The Town will monitor the permitted dredged area, and sediment accumulation (infill)
rates within Jay Bird Shoals, including all areas located 500 feet outside of the dredged
area, for a period of three years after dredging. The first survey should be completed
within 30 days upon completion of dredging.

Reporting
• The Town will notify the state and federal resource agencies in the event the contractor
is able to remove the marine debris intact. Any marine debris encountered during
dredging operations will be disposed of in an appropriate location. If any submerged
cultural resources are encountered during dredge operations, the contractor will cease
dredging immediately.
• All shoreline monitoring reports will be submitted to the State and Federal resource
agencies by December 31 of each year.

Threatened and Endangered Species
• Based on recommendations by USFWS and NCWRC, the dune slope design was adjusted
to 4H:1V on the oceanfront side to avoid sea turtles and hatchlings becoming entrapped
on the backside of the dune.
• West Indian Manatee Protection – the contractor will implement the USFWS’s Manatee
Guidelines found at http://saw-reg.usace.army.mil/ESA/manatee_guidelines.pdf.
• Sea Turtle Incidental Data Form - If a sea turtle or its remains are found during dredging,
a Sea Turtle Incidental Data Form will be completed and submitted to the ODESS database
as soon as possible (not to exceed 6 hours after the incident).

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• Sturgeon Incidental Data Form - If a sturgeon or its remains are found during dredging, a
Sturgeon Incidental Data Form must be completed and submitted to the ODESS database
as soon as possible (not to exceed 6 hours after the incident).
• During dredging, observers approved by the National Oceanic and Atmospheric
Administration – Fisheries for sea turtles, sturgeon, and whale will be aboard to monitor
for presence of the species.
• To protect NC Division of Marine Fisheries (DMF) Artificial Reef 425, a 2,000 ft radius will
be maintained in all directions from a center point location of 33°53.048’ N, -78°06.525’
W.
• To protect NC DMF Artificial Reef 430, a 2,000 ft radius will be maintained in all directions
from a center point location of 33°52.1898’ N, -78°10.0002’ W.

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Figure 4-1. Post-Construction Monitoring of Caswell Beach

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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. The project property is within the planning jurisdiction of Brunswick County and
the Town and is classified “Developed” by the CAMA Land Use Plan.
6.0 COMPLIANCE WITH THE NC ENVIRONMENTAL POLICY ACT
In accordance with § 113A-12(6), NCDCM has determined prior to the application that review of
this project under the State Environmental Policy Act is not be required.
The NC Division of Water Resources will be provided a full copy of the permit application
requesting a 401 Water Quality Certification.
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 H).
8.0 COMPLIANCE WITH DWR WATER QUALITY CERTIFICATION
In accordance with 15A NCAC 07H.0208(a)(2)(B), a scoping meeting occurred in lieu of a pre-filing
meeting request. The scoping meeting was held virtually (via WebEx) on October 23, 2020. A
summary of the scoping meeting is provided in Appendix I.
As requested by NCDCM after the scoping meeting, several supplemental profiles which display
historical surveys overlain with the construction template are provided in Appendix J.
The project proponent hereby certifies that all information contained herein is true, accurate,
and complete to the best of my knowledge and belief.
The project proponent hereby requests that the certifying authority review and take action on
this CWA 401 certification request within the applicable reasonable period of time.

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9.0 REFERENCES
Berkowtiz, J.F., VanZomeren, C.M., and Priestas, A.M. 2018. Investigation Sediment Color Change
Dynamics to Promote Beneficial Use Applications. The Proceedings of 2018 Dredging Summit and
Expo.

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.

Maglio, C., Ousley, J.D., and Coor, J.L. 2015. “Sediment engineering thru dredging and with nature
– fate of fines in dredging and placement process.” The Proceedings of Coastal Sediments 2015,
San Diego, CA.

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.

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NCDCM Major Permit Modification #31-20 Moffatt & Nichol
2021/2022 Oak Island Renourishment Project November 2020
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