HomeMy WebLinkAbout19971000 Ver 1_Complete File_19971114State of North Carolina
Department of Environment,
Health and Natural Resources `
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary p E H N F1
A. Preston Howard, Jr., P.E., Director
November 14, 1997
C.E. Shuford, Jr., P.E.
U.S. Army Corps of Engineers - Wilmington District
Post Office Box 1890
Wilmington, NC 28402-1890
Dear Mr. Shuford:
Re: Certification Pursuant to Section 401 of the Federal Clean Water Act,
Proposed Drum Inlet Maintenance Dredging
WQC Project #971000
Carteret County
Attached hereto is a copy of Certification No. 3166 issued to U.S. Army Corps of
Engineers dated November 14, 1997.
If we can be of further assistance, do not hesitate to contact us.
Attachments
3166wgc
cc: Wilmington District Corps of Engineers
Corps of Engineers Wilmington Field Office
Wilmington DWQ Regional Office
Mr. John Dorney
Mr. John Parker, Division of Coastal Management
Central Files
Division of Water Quality • Environmental Sciences Branch
Enviro. Sciences Branch, 4401 Reedy Creek Rd., Raleigh, NC 27607 Telephone 919-733-1786 FAX # 733-9959
An Equal Opportunity Affirmative Action Employer • 50% recycled/10% post consumer paper
NORTH CAROLINA 401 WATER QUALITY CERTIFICATION
THIS CERTIFICATION is issued in conformity with the requirements of Section 401
Public Laws 92-500 and 95-217 of the United States and subject to the North Carolina
Division of Water Quality (DWQ) Regulations in 15 NCAC 2H, Section .0500 to U.S. Army
Corps of Engineers for the use of overflow or side cast dredge for additional maintenance
dredging methods for Drum Inlet, in Carteret County pursuant to an application dated the
29th day of August 1997.
The application provides adequate assurance that the dredging of disposal material from
the waters of Drum Inlet in conjunction with the proposed development will not result in a
violation of applicable Water Quality Standards and discharge guidelines. Therefore, the
State of North Carolina certifies that this activity will not violate the applicable portions of
Sections 301, 302, 303, 306, 307 of PL 92-500 and PL 95-217 if conducted in accordance
with the application and conditions hereinafter set forth.
This approval is only valid for the purpose and design that you submitted in your
application, as described in the Public Notice or as modified below. If you change your
project, you must notify us and you may be required to submit a revised application. If total
wetland fills for this project (now or in the future) exceed one acre, compensatory mitigation
may be required as described in 15A NCAC 2H .0506 (h) (6) and (7). For this approval to
be valid, you must follow the conditions listed below. In addition, you should get any other
federal, state or local permits before you go ahead with your project including (but not
limited to) Sediment and Erosion control, Coastal Stormwater, Non-discharge and Water
Supply watershed regulations.
Condition(s) of Certification:
1. Appropriate sediment and erosion control practices which equal or exceed those
outlined in the most recent version of the "North Carolina Sediment and Erosion Control
Planning and Design Manual" or the "North Carolina Surface Mining Manual" (available
from the Division of Land Resources in the DEHNR Regional or Central Offices) shall
be utilized to prevent exceedances of the appropriate turbidity water quality standard (50
NTUs in all fresh water streams and rivers not designated as trout waters; 25 NTUs in all
lakes and reservoirs, and all saltwater classes; and 10 NTUs in trout waters);
2. If dredging occurs in areas of less than 90% sand while dredging Tangent A in the
vicinity of E2800000 and N41800, monitoring of turbidity levels in the SAV to the
southeast should be carried out to determine the lateral extent of the sediment plume
from outside the channel axis environs. Monitoring will be for surface levels (i.e. 1-foot
depth) of turbidity.
3. If turbidity levels at this SAV bed exceed 25 NTUSs, dredging operations shall be
suspended until it can be demonstrated that these dredging activities can be continued
without violations of this standard.
Violations of any condition herein set forth shall result in revocation of this Certification
and may result in criminal and/or civil penalties. This Certification shall become null and
void unless the above conditions are made conditions of the Federal 404 and/or coastal Area
Management Act Permit. This Certification shall expire upon expiration of the 404 or
CAMA permit.
If this Certification is unacceptable to you you have the right to an adjudicatory hearing
upon written request within sixty (60) days following receipt of this Certification. This
request must be in the form of a written petition conforming to Chapter 150B of the North
Carolina General Statutes and filed with the Office of Administrative Hearings, P.O. Box
27447, Raleigh, N.C. 27611-7447. If modifications are made to an original Certification,
you have the right to an adjudicatory hearing on the modifications upon written request
within sixty (60) days following receipt of the Certification. Unless such demands are made,
this Certification shall be final and binding.
This the 14th day of November 1997
WQC 971000
DIVISION OF WATER QUALITY
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
19
[D F= F1
Division of Water Quality
Environmental Sciences Branch
4401 Reedy Creek Road
Raleigh, N.C. 27607
FAX:(919) 733-9959
Date 1I 1 1 ?
FAX TO: ?-1-An V YOl (,?i 1Cy? I FAX NUMBER: 4 f 0 - 251- ¢ a tTA
FROM: i , != (C
PHONE:
NO. OF PAGES INCLUDING THIS SHEET:
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Environmental Sciences Branch 4401 Reedy Creek Road Raleigh, North Carolina 27607
Telephone 919-733-9960 FAX # 733-9959
An Equal Opportunity Affirmative Action Employer 500/6 recycled/10% post consumer paper
*-
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
A4
E)EHNR
?,?o??C??3A' (4--11997
5 fb
a-te90
Dear Mr. U f ,
Re: CertificationTursuant to Section 401 of the Fed Clean , water Act,
Proposed Uram (?f Mw?/! den A ?.c l gag
Project
a
re C4? . ? County oQ
(4(
Attached hereto is a copy of Certification o. ' sued to dated 1997.
If we can be of further assistance, do not hesitate to contact us.
Sincerely,
A. Preston Howard, Jr. P.E.
Attachments
?d wqc
cc: Wilmington District CQ?ps o Engineers
of En ' gineers M t field Office
DWQ Regional Office
Mr. John orney
Mr. John Parker, Division of Coastal Management
Central Files
Division of Water Quality - Environmental Sciences Branch
Enviro. Sciences Branch, 4401 Reedy Creek Rd., Raleigh, NC 27607 Telephone 919-733-1786 FAX # 733-9959
An Equal Opportunity Affirmative Action Employer • 50% recycled/10% post consumer paper
NORTH CAROLINA 401 WATER QUALITY CERrYI ICATION
J(? 6 ?- Ver' (%-Jor St Akcci(- Bred {or addi ;ono
7?aC Mae koranctfdredttgo MovkoA
T ERTIFICATION is iss ed in conformity with the requirements of Section 'r 01-*?
401 Pub ' Laws 92-500 and 95-217 of the United States and subject to the North Carolina 1?1
Divisio of Water Qu&li (DW egulations in 15 NCAC 211, Section .0500 to io v. 5. AtMY (drp5 c F
ca?eit MAIM in (' re County pursuant ?,,5 rS
to an application ie_th day of 199-Lti-
Oki) pcim
The appli cation vides adequate assurance that the f , Material W6 the
waters of DrdM in conjunction with the proposed development will not result
in a violation of applicable Water Quality Standards and discharge guidelines. Therefore,
the State of North Carolina certifies that this activity will not violate the applicable portions
of Sections 301, 302, 303, 306, 307 of PL 92-500 and PL 95-217 if c nducted m/
accmince with th appli c?lion and conditions here' after set orth. ?ei? P r?0 t?
?a eh I,t1a`k? Q??l{t N? 7 ?s?l °Y'
This approval is only valid for the purpose and design that you submitted in your
application, as described in the Public Notice or as modified below. If you change your
project, you must notify us and you may be required to submit a revised application. If
u S
total wetland fills for this project (now or in the future) exceed one acre, compensatory
mitigation may be required as described in 15A NCAC 2H .0506 (h) (6) and (7). For this
approval to be valid, you must follow the conditions listed below. In addition, you should
get any other federal, state or local permits before you go ahead with your project including s
(but not limited to) Sediment and Erosion control, Coastal Stormwater, Non-discharge and JA"
Water Supply watershed regulations.
Condition(s) of Certification:
1. Appropriate sediment and erosion control practices which equal or exceed those
outlined in the most recent version of the "North Carolina Sediment and Erosion
Control Planning and Design Manual" or the "North Carolina Surface Mining Manual"
(available from the Division of Land Resources in the DEHNR Regional or Central
Offices) shall be utilized to prevent exceedances of the appropriate turbidity water
quality standard (50 NTUs in all fresh water streams and rivers not designated as trout
waters; 25 NTUs in all lakes and reservoirs, and all saltwater classes; and 10 NTUs in
trout waters);
If dredging occurs in areas of less than 90% sand while dredging Tangent A in the vicinity of
E2800000 and N418000, monitoring of turbidity levels in the SAV to the southeast should be carried
out to determine the lateral extent of the sediment plume from outside the channel axis environs.
Monitoring will be for surface levels (i.e. 1-foot depth) of turbidity.
If turbidity levels at this SAV bed exceed 25 NTUSs, dredging operations shall be suspended until it
can be demonstrated that these dredging activities can be continued without violations of this standard.
vuquUVa UIIW tv jJ ttaw.?vau?,yv.,uv+++M VO?ya w...n,.,V.?"?-v'rT?
Violations of any condition herein set forth shall result in revocation of this
Certification and may result in criminal and/or civil penalties. This Certification shall
become null and void unless the above conditions are made conditions of the Federal 404
and/or coastal Area Management Act Permit. This Certification shall expire upon expiration
of the 404 or CAMA permit.
If this Certification is unacceptable to you you have the right to an adjudicatory hearing
upon written request within sixty (60) days following receipt of this Certification. This
request must be in the form of a written petition conforming to Chapter 150B of the North
Carolina General Statutes and filed with the Office of Administrative Hearings, P.O. Box
27447, Raleigh, N.C. 27611-7447. If modifications are made to an original Certification,
you have the right to an adjudicatory hearing on the modifications upon written request
within sixty (60) days following receipt of the Certification. Unless such demands are
made, this Certification shall be final and binding.
This the l th day of ? OJ c44%7
DIVISION OF WATER QUALITY
A. Preston Howard, Jr. P.E.
60(o
WQC #
go ? ou,
C.r
RECEIVED
DEPARTMENT OF THE ARMY
Wilmington District, Corps of Engineers
Post Office Box 1890
Wilmington, North Carolina 28402-1890 COASTAL MANAGEMENT
CESAW-EP-PE-97-16-0014 August 29, 1997
PUBLIC NOTICE
AND
NOTICE OF AVAILABILITY
ENVIRONMENTAL ASSESSMENT
USE OF HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
TO WHOM IT MAY CONCERN:
Construction of the Drum Inlet channel was completed in March 1997. Maintenance of
the connecting channel (Tangents A, B, and C) (figure 1) was anticipated to be every 2-3 years
with a volume of 100,000 cubic yards. Maintenance was to be performed by a hydraulic
pipeline dredge with disposal on the beach of Core Banks. However with experience following
construction, maintenance in the connecting channel will probably be every 3-6 months with
30,000 - 90,000 cubic yards of sand removed during each event. Because of the increased
frequency with relatively small volumes, the U.S. Army Corps of Engineers sidecast dredges
and hopper dredge CURRITUCK need to be added as maintenance dredging options for the
connecting channel.
A sidecast dredge has two drag arms (one on each side) that "vacuum" the sediment as
the arms drag along the bottom. The sediment is pumped through a discharge pipe that is
above the water surface and perpendicular to the dredge. The discharge pipe extends about
60 feet beyond the side of the dredge. This pipe distance and force from the pumps generally
results in the sediment being deposited 85 to 100 feet from the dredge. The sediment is
discharged on the side of the channel where the predominant currents would tend to move the
sediment away from the channel. The U.S. Army Corps of Engineers has three sidecast
dredges (all operated by the Wilmington District), and one would generally be available to
maintain Drum Inlet.
V
The hopper dredge CURRITUCK has drag arms similar to a sidecast dredge, but the
sediment is pumped into the dredge's hopper. The water in the hopper is overflowed to
provide an economic load of sand since the dredged slurry entering the hopper contains about
20 percent sand and 80 percent water. Once the hopper is full of sand (about 300 cubic
yards), the sediment is taken to nearshore ocean waters (normally -6 to -10 feet mean low
water) where the split hull hopper is opened and the sediments are deposited. The
CURRITUCK is the only small hopper dredge the U.S. Army Corps of Engineers has (operated
by the Wilmington District) that is capable of maintaining Drum Inlet, and commercial hopper
dredges as small as the CURRITUCK do not exist. Due to the high demand for this dredge
outside the District, it is only available in North Carolina about 6 months each year (August -
October and December-February). When available, the CURRITUCK will be used, instead of
a sidecast dredge, for removal of shoals in the connecting channel.
Due to recreational fishing and sea turtle and colonial waterbird nesting, hydraulic
pipeline dredging with disposal on the beach of Core Banks is permitted from December 15 to
March 31. Since shoals block the connecting channel at other times of the year, the sidecast
dredge or the hopper dredge CURRITUCK may be needed at any time of the year.
The Drum Inlet environment is discussed in detail in the 1995 environmental assessment
(EA):
U.S. Army Corps of Engineers, Wilmington District. 1995. Environmental Assessment,
Maintenance of Drum Inlet Carteret County, North Carolina. Environmental Resources
Section. January 1995.
The EA, made available by this notice, primarily adds information related to turbidity and
suspended sediment monitoring data collected April 22, 1997, during the operation of the
sidecast dredge FRY.
A Section 401 (P.L. 95-217) Water Quality Certificate is required for overflow of the
hopper dredge and discharge from the sidecast dredge. A Section 401 Water Quality
Certification has been requested from the North Carolina Division of Water Quality. A Section
404(b)(1) (P.L. 95-217) evaluation report for the overflow of the hopper dredge and discharge
from the sidecast dredge has been prepared and included in the EA.
The work will not affect any species currently on the Federal list of threatened or
endangered species. The proposed work has been evaluated pursuant to the provisions of
the National Historic Preservation Act of 1966, as amended. No known archaeological or
historical resources will be affected by the proposed action. A list of Federal, State, and local
agencies with whom this activity is being coordinated is included in the EA.
The decision whether to perform this work will be based on an evaluation of the probable
impact, including cumulative impacts of the proposed activity on the public interest. That
decision will reflect the national concern for both protection and utilization of important
resources. The benefits which may reasonably be expected to accrue from the proposal must
be balanced against its reasonably foreseeable detriments. All factors which may be relevant
t
to the proposal will be considered, including the cumulative effects thereof; among those are
conservation, economics, aesthetics, general values, flood hazards, flood plain values, land
use, navigation, shoreline erosion and accretion, recreation, water supply and conservation,
water quality, energy needs, safety, food and fiber production, mineral needs, considerations
of property ownership, and in general, the needs and welfare of the people.
This notice is being distributed to all known interested persons concurrent with circulation
of the EA. For accuracy and completeness of record, all data in support of or in opposition to
the work should be submitted in writing within 30 days of the date of this notice setting forth
sufficient detail to support convictions. Any person who has an interest which may be affected
by the proposed action may request a public hearing. The request must be submitted in
writing to the District Engineer within 30 days of the date of this notice and must clearly set
forth the interest which may be affected and the manner in which the interest may be affected
by this activity. All correspondence should refer to the title, number, and date of this notice.
For further information or to receive a copy of the EA, contact Mr. Frank Yelverton, U.S. Army
Corps of Engineers, Post Office Box 1890, Wilmington, North Carolina 28402-1890, telephone
(910) 251-4640.
<-
61-1
C. E. Sh ord, Jr., P.E.
Acting Chief, Engineering
and Planning Division
Attachment
N420000
N417500
N415000
N412600
i
N410000
N4076M
1997 PHOTOGRAPHY
SEAGRASS
BEDS ON
AT
INLET, NC
DRUM
SCALE: 1" = 2000' pripr
1996 GRASS BEDS
1997 GRASS BEDS
Feet
2000 0 2000 4000
GRID BASED ON NORTH CAROLINA STATE PLANE (NAD83) DC' E W a EROMMM
vnu+rtirox.? w?aru er:
DATE OF PHOTOGRAPHY: MAY 17.1997
1997 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY
DATED MAY 17
1997 AMERICAN GEOGRAPHIC DATA INC.
5710 OLEANDER DRIVE SUITE 108
,
1996 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY WILMINGTON. NC 28403
(910)392-1496
DATED MAY 23.1996
E2797500 E2800000 E2802500 E2805000 E2807500 E281
FIGURE !.
N420000
N4175W
N415000
N412500
N410000
N407500
RECEIVED
Ismaili
1C' J >.
US ARMY CORPS COASTAL MANAGEMENT
OF ENGINEERS
Wilmington District
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
AUGUST 1997
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
TABLE OF CONTENTS
Heading Page No.
1.00 PROJECT DESCRIPTION .....................................................................................1
2.00 PURPOSE AND NEED ..........................................................................................1
3.00 DREDGING AND DISPOSAL METHODS ..............................................................2
3.01 Hydraulic Pipeline Dredge ............................................... ...........................2
3.02 Sidecast Dredges and the Hopper Dredge CURRITUCK ...........................3
4.00 ENVIR ONMENTAL EFFECTS .................................................... ...........................4
4.01 Water Quality ................................................................... ...........................4
4.02 Aquatic Resources .......................................................... ...........................5
4.03 Endangered Species ....................................................... ...........................8
4.04 Development and Economic Justification ........................ ...........................9
4.05 Inlet Stability .................................................................... ...........................9
5.00 COORDINATION ..................................................................................................10
6.00 CONSISTENCY DETERMINATION FOR NORTH CAROLINA COASTAL
MANAGEMENT PROGRAM ............................................................................10
7.00 LIST OF RECIPIENTS .........................................................................................10
8.00 POINT OF CONTACT ..........................................................................................13
9.00 ENVIRONMENTAL COMMITMENTS ...................................................................13
10.00 REFERENCES ...................................................................................................14
11.00 FINDING .............................................................................................................14
4
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
TABLE OF CONTENTS (cont'd)
TABLES
(Follows Page 14)
TABLE 1. Sidecast Dredge Discharge in Tangent A, Drum Inlet, North Carolina.
TABLE 2. Sidecast Dredge Discharge in Tangent B, Drum Inlet, North Carolina.
TABLE 3. Shoals Enlarged by Sidecast Dredging at Drum Inlet, North Carolina.
FIGURES
(Follows Tables)
FIGURE 1. Seagrass Beds on 1997 Photography at Drum Inlet, North Carolina.
ATTACHMENTS
(Follows Tables and Figures)
ATTACHMENT A. Evaluation of Section 404(b)(1) Guidelines.
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
August 1997
1.00 PROJECT DESCRIPTION
The maintenance of Drum Inlet was discussed in detail in the
environmental assessment (EA) dated January 1995, and letter amendment
dated April 28, 1995 (U.S. Army Corps of Engineers (USACE), 1995a).
According to that EA, maintenance of the bar channel (inlet area, seaward of
Tangent C, figure 1) would be by sidecast dredge or the hopper dredge
CURRITUCK and maintenance of the connecting channel (Tangents A, B, and
C) would be by hydraulic pipeline dredge with disposal on the beach of Core
Banks. This new EA adds using a sidecast dredge or the hopper dredge
CURRITUCK for the maintenance of the connecting channel.
Maintenance frequency of the connecting channel was anticipated to be
every 2-3 years with a volume of 100,000 cubic yards. However with experience
following construction, maintenance in the connecting channel will probably be
every 3-6 months with 30,000-90,000 cubic yards of sand removed during each
event. Because of the increased frequency with relatively small volumes the
sidecast dredges and the CURRITUCK need to be added as maintenance
options for the connecting channel. Disposal by the sidecast dredge would be
either north or south of the channel depending on which way the predominant
current is flowing (generally north during the warmer months and south during
the cooler months). The CURRITUCK would dispose of the sand in the
nearshore ocean area.
2.00 PURPOSE AND NEED
The purpose of this EA is to discuss the need for and impacts of using a
sidecast dredge or the hopper dredge CURRITUCK with overflow as additional
maintenance dredging methods for the Drum Inlet connecting channel. This EA
is also intended to amend the EA for the Maintenance of Drum Inlet, Carteret
County, North Carolina (USACE, 1995a) to include these additional
maintenance methods.
The following reasons show why these additional maintenance methods
are needed:
a. Maintenance frequency of the connecting channel is greater than
anticipated.
b. Due to recreational fishing and sea turtle and colonial waterbird
nesting, hydraulic pipeline dredging with disposal on the beach of Core Banks is
permitted from December 15 to March 31. Shoals block the connecting channel
at other times of the year.
c. Mobilizing a hydraulic pipeline dredge with 1-2 miles of pipeline to the
beach disposal area for small shoals is not practical.
The following are in addition to the indicated need:
a. Sidecast dredging and hopper dredging with overflow in the connecting
channel should not adversely impact the environment.
b. The increased frequency of maintenance of the connecting channel will
not alter the economic justification of the project, due to the efficiency of the
sidecast dredge and the CURRITUCK.
3.00 DREDGING AND DISPOSAL METHODS
The existing and proposed dredging and disposal methods in the
connecting channel are described below:
3.01 Hydraulic Pipeline Dredge. According to USACE, 1995a, only
maintenance dredging in the connecting channel is allowed by hydraulic pipeline
dredge. The dredged material would be pumped to the beaches of Core Banks
north or south of the inlet and placed below the limit of the wave uprush zone to
minimize alterations and impacts to the upland portion of the beach. The wave
uprush zone is the part of the beach wetted by the normal wave uprush. The
beach is owned by the National Park Service, Cape Lookout National Seashore
(Service), and a Special Use Permit is required from the Service prior to any
disposal activities. Maintenance efforts in this channel with a hydraulic pipeline
dredge were anticipated to involve dredging approximately 100,000 cubic yards
every 2-3 years. This maintenance would be done at the same time as the
maintenance of the waterway in Core Sound in order to eliminate the high cost
for separate mobilization.
2
Hydraulic pipeline dredging is restricted to the connecting channel
because seaward of Tangent C (figure 1) the wave environment is too intense
for conventional pipeline dredge operations. The channel dimensions are too
restrictive for use of an ocean-certified pipeline dredge.
Initial dredging of the connecting channel was completed by hydraulic
pipeline dredge in March 1997. After the dredge left the area, the channel
began to rapidly shoal. Therefore under emergency procedures (Memorandum
of Agreement [MOA] between the Wilmington District and the North Carolina
Department of Environment, Health, and Natural Resources, signed December
1986), the sidecast dredge FRY removed about 88,000 cubic yards of sand from
the connecting channel between April 11 and 30, 1997. This material was
deposited adjacent to the north side of Tangents A and B (figure 1), since north
was the predominant direction the currents were flowing. Emergency dredging
was again required under the MOA in early August 1997, just prior to publication
of this EA. The CURRITUCK was to remove about 50,000 cubic yards from the
connecting channel with disposal in the nearshore ocean waters.
3.02 Sidecast Dredges and the Hopper Dredge CURRITUCK. Sidecast
dredging with disposal adjacent to the channel is currently only allowed for
maintenance of the bar channel with disposal adjacent to the channel. Hopper
dredging with the CURRITUCK is currently only allowed for maintenance of the
bar channel with disposal in nearshore ocean waters.
A sidecast dredge has two drag arms (one on each side) that "vacuum" the
sediment as the arms drag along the bottom. The sediment is pumped through a
discharge pipe that is above the water surface and perpendicular to the dredge.
The discharge pipe extends about 60 feet beyond the side of the dredge. This
pipe distance and force from the pumps generally results in the sediment being
deposited 85 to 100 feet from the dredge. The sediment is discharged on the
side of the channel where the predominant currents would tend to move the
sediment away from the channel. The U.S. Army Corps of Engineers has three
sidecast dredges (all operated by the Wilmington District), and one would
generally be available to maintain Drum Inlet.
The CURRITUCK has drag arms similar to a sidecast dredge, but the
sediment is pumped into the dredge's hopper. The water in the hopper is
overflowed to provide an economic load of sand, since the dredged slurry
entering the hopper contains about 20 percent sand and 80 percent water.
Once the hopper is full of sand (about 300 cubic yards), the sediment is taken to
nearshore ocean waters (normally -6 to -10 feet mean low water [m.l.w.]) where
the split hull hopper is opened and the sediments are deposited. The
CURRITUCK is the only small hopper dredge the U.S. Army Corps of Engineers
has (operated by the Wilmington District) that is capable of maintaining Drum
3
Inlet, and commercial hopper dredges as small as the CURRITUCK do not exist.
Due to the high demand for this dredge outside of the District, it is only available
in North Carolina about 6 months each year (August - October and December-
February). When available, the CURRITUCK will be used, instead of a sidecast
dredge, for removal of shoals in the connecting channel.
The use of the sidecast dredge and the CURRITUCK will probably be
needed for maintenance of the connecting channel every 3-6 months year-
round. As detailed below, these maintenance alternatives and anticipated
frequency should have minimal impact on the environment.
4.00 ENVIRONMENTAL EFFECTS
The Drum Inlet environment is discussed in detail in USACE, 1995a. This
EA will primarily add information related to the monitoring data collected
April 22, 1997, while the sidecast dredge FRY was operating under emergency
procedures in the Drum Inlet connecting channel.
4.01 Water Quality. The North Carolina water quality classification
assigned to the Drum Inlet area (White Oak Basin) is SA/ORW. SA waters are
suitable for commercial shellfishing and all other tidal salt water uses including
primary and secondary recreation, and fish propagation. ORW (Outstanding
Resource Waters) are unique and special waters of exceptional state or national
recreation or ecological significance which require special protection to maintain
existing uses. The North Carolina Division of Water Quality (NCDWQ) standard
for turbidity for SA/ORW is 25 NTU's. There is no NCDWQ suspended sediment
standard for the area.
Two discharge events from the sidecast dredge FRY were monitored in the
connecting channel where the dredge was working on April 22, 1997. The first
discharge monitored on the dredged material was from the western to the
eastern end of Tangent A. The sediments in Tangent A are about 94 percent
sand and represents the lowest percentage of sand in the connecting channel
since Tangent A is the greatest distance from the inlet. Table 1 generally
indicates a major reduction in suspended sediment concentration and turbidity
with distance from the dredge (the low value at the surface 100 feet from the
discharge pipe was probably due to sampling a clear water pocket). Both
parameters neared background values at 1,500 feet from the dredge. Samples
were not taken beyond 1,500 feet because the turbidity plume associated with
the discharge was no longer visibly evident.
The surface and bottom background turbidity values measured April 22,
1997, were both below 25 NTUs (6 and 14, respectively). At 1,500 feet from the
4
dredge during the discharge test, both the surface and bottom values were 25
NTUs or less (Table 1). This turbidity plume is generally confined to the near
channel area out to 1,500 feet since the dredge is steering into tidal currents
averaging about 1 knot.
The second discharge monitored on the dredged material was from the
eastern to western end of Tangent B. The sediments in Tangent B are about 95
percent sand and contain a higher percentage of sand than Tangent A since
Tangent B is closer to the inlet. Table 2 indicates a general reduction in
suspended sediment concentration and turbidity with distance from the dredge.
Both parameters neared background values at 2,000 feet from the dredge.
Samples were not taken beyond 2,000 feet because the turbidity plume
associated with the discharge was no longer visibly evident.
The surface and bottom background turbidity values for the second
discharge were also both below 25 NTUs (9 and 13, respectively). At 2,000 feet
from the dredge during the discharge test, both the surface and bottom values
were less than 25 NTUs (table 2). As with the first test, the turbidity plume is
generally confined to the near channel area out to 2,000 feet since the dredge is
steering into tidal currents averaging about 1 knot.
Monitoring of turbidity and suspended solids levels in the overflow from the
CURRITUCK has not been performed. However, since the purpose of the
CURRITUCK is to retain sediment in the hopper, the turbidity and suspended
solids levels in the overflow should be less than that monitored for the sidecast
dredge FRY.
Based on the above information, the proposed action should not adversely
impact water quality.
The North Carolina Division of Water Quality will concurrently review this
EA and the U.S. Army Corps of Engineers' request for a Section 401 (P.L. 95-
217) Water Quality Certificate to authorize the work that may impact water
quality under the proposed action. Also, the Section 404(b)(1) evaluation for the
discharge of dredged material is included (Attachment A).
4.02 Aquatic Resources. The only changes to resources from the 1995
Drum Inlet EA (USACE, 1995a) are (1) the increased turbidity and suspended
solids levels associated with discharge from the sidecast dredge and overflow
from the CURRITUCK, and (2) enlarging existing shoals adjacent to the
channel where the sidecast dredge discharges and deposition in the near
shore ocean area by the CURRITUCK.
5
Increased Turbidity and Suspended Solids Levels. As indicated in
section 4.01, the increased turbidity and suspended solids levels associated with
discharge from the sidecast dredge return to background or near background
levels relatively close to the dredge. The dredges could perform maintenance
work at Drum Inlet for 24 weeks every 3-6 months, but when onsite the dredges
do not work continuously. The sidecast dredge usually operates 10 hours per
day (6:00 a.m. to 4:00 p.m.). The sidecast may dredge a shoal for 20-30
minutes, and take another 20-30 minutes to reposition the dredge at the
beginning of the shoal (vessel heads into the current to maintain steerage).
Considering repositioning time and run time to and from the dock at the
beginning and end of the 10-hour day, the dredge may be moving sediment on
an intermittent basis 4-5 hours per day.
The hopper dredge CURRITUCK also operates about 10 hours per day.
This vessel dredges an average of 20 minutes to load the hopper (about 300
cubic yards), but about 30-40 additional minutes are needed for a round trip to
the nearshore ocean disposal location. Considering round trip time to the ocean
and run time to and from the dock at the beginning and end of the 10-hour day,
the dredge may be moving sediment and overflowing the hopper on an
intermittent basis 3-4 hours per day.
Due to the low levels of turbidity and suspended solids, intermittent
occurrence, small relative area affected, and lack of primary nursery areas in the
vicinity, marine fishery resources should not be adversely affected.
Enlarging Existing Shoals and Deposition in the Nearshore Ocean
Area. All the sediment excavated by a sidecast dredge is deposited adjacent to
the channel where the predominant currents will tend to reduce return of the
sediments to the channel. For example, all the sediments removed by the
sidecast dredge FRY in April 1997 (87,649 cubic yards, 18 days of the period
April 11 - 30, 1997) were placed on the north side of the channel because the
predominant current was running north. According to the captain of the sidecast
dredge FRY, this deposition raised elevation of the shoals adjacent to the
channel up to 2-3 feet in a total of 3 areas adjacent to the north side of Tangents
A and B. The elevation change of the areas affected by the discharge can not
be accurately determined since a pre-dredging elevation survey was not taken
that included the existing shoaled areas adjacent to the channel.
Aerial photography was taken of the Drum Inlet area on February 16, 1997
(shortly after hydraulic pipeline dredging began in the connecting channel and
was still in Tangent A), and on May 17, 1997, after the emergency sidecast
dredging was complete. Comparison of the photography from these dates
indicates that the areas where the sidecast dredge deposited the sand were
6
existing shoals, with some of the area on the February photography appearing
intertidal. However, the May 17, 1997, photographs do appear to indicate more
intertidal areas adjacent to the north side of the channel than the February
photographs.
Extensive elevation surveys were performed on May 20 and July 22, 1997
(after emergency sidecast dredging), in the area within 300 feet of the north
edge of Tangents A and B. This data is summarized in table 3. In the area
surveyed on May 20, 1997, about 0.38 acres were 6 inches or less above mean
high water (m.h.w.), and 5.41 acres were above m.l.w. The rest of the area was
subtidal. As indicated above, some of this area was probably intertidal before
sidecast dredging began. The same area was again surveyed on July 22, 1997.
On July 22, 1997, no areas remained above m.h.w., and 3.87 acres were above
m.l.w. (intertidal). Between the May and July surveys, about 55 percent of the
volume of sand on the shoals was dispersed by wind waves and currents in the
open sound. Since this change occurred in about two months, establishing a
permanent area above m.h.w. should be precluded because of an anticipated
maintenance frequency of 3-6 months, and when available, the CURRITUCK will
be used, instead of a sidecast dredge, for removal of shoals in the connecting
channel.
However, these elevated areas could become permanent features. If so,
benthic resources in the shoals would be suppressed if sidecast dredging is
frequent. Nevertheless, these areas could provide some habitat enhancement
such as loafing and foraging areas for waterbirds, and seagrass beds could
establish on the leeward side of the shoals. This condition will be monitored for
at least the first 2 years of maintenance. Monitoring will include change in
elevation and areal extent of the shoals, and establishment of seagrass beds.
The Drum Inlet area is heavily used by commercial and recreational
fishermen. For example, the area is open to the mechanical harvest of clams
(North Carolina Division of Marine Fisheries [NCDMF], 1997). During each
dredging event, the areas where disposal occurs will be at least temporarily
unavailable (due to decreased water depth) for mechanical harvesting.
Excluded from the mechanic harvest area are oyster and clam leases and known
seagrass beds. No leases are located near the project area. Several leases are
located on the mainland near Atlantic, and one lease is located on the Core
Banks side about 6 miles south of Drum Inlet. Therefore, no leases will be
affected by the proposed action.
Based on seagrass mapping, no seagrasses are within 800 feet of the
channel alignment (figure 1). This mapping was based on May 23, 1996, and
7
May 17, 1997, aerial photography; and July 22, 1997, field verification of the
May 1997 photography. Due to the distance to the nearest grass beds, dredging
of the connecting channel by sidecast dredges or the hopper dredge
CURRITUCK should not impact these resources.
The CURRITUCK will dispose of up to 300 cubic yards of sand in the
nearshore (6-10 feet m.l.w.) ocean area during each dredging cycle (up to 10
times per 10-hour day). The sand disposed in the active wave environment will
quickly dissipate and should not appreciably affect the nearshore environment.
4.03 Endangered Species. The proposed action will not affect listed
species under the jurisdiction of the U.S. Fish and Wildlife Service (USFWS) or
the National Marine Fisheries Service (NMFS). Endangered species were
discussed in USACE, 1995a. That EA also discussed the year-round use of the
sidecast dredges and the hopper dredge CURRITUCK in the inlet. The May 2,
1995, Biological Assessment also discussed two species (piping plover and
seabeach amaranth) under the jurisdiction of the USFWS (USACE, 1995b). The
NMFS in their letter dated January 31, 1995, did not indicate impacts on listed
species, and the USFWS provided their Biological Opinion on June 30, 1995
(USFWS, 1995). This EA would extend the operation of the sidecast dredges
and the CURRITUCK year-round into the connecting channel as an additional
method of maintenance dredging.
The NMFS listed species have not changed since the 1995 EA. As
indicated in the 1995 EA for species under the NMFS jurisdiction, the operation
of sidecast dredges and the hopper dredge CURRITUCK are not believed
harmful to sea turtles because of the small size of the dragheads, slow speed of
the vessels, and the low suction levels (NMFS, 1991). None of the whales
should be impacted by the proposed action since all the dredging, disposing,
and maneuvering actions would be in the sound or close to the beach and in
shallow water. The shortnose sturgeon has been documented recently for the
Cape Fear River (Moser and Ross, 1993), but no other populations are known
from North Carolina. Therefore, species under the NMFS jurisdiction will not be
affected by the additional maintenance methods.
The only listed species change since the 1995 EA under the USFWS
jurisdiction that may occur in waters affected by the additional proposed
maintenance methods is the manatee (Trichechus manatus). The manatee is a
rare visitor to the area. All of the presently designated critical habitat is in
Florida. From 1919 to 1994 a total of 13 manatees had been observed in
Carteret County (an average of less than one every 5 years), with the most
observed in any year was two. The nearest observation to Drum Inlet was of a
8
single individual at Davis in September 1983 and 1993, about 10 miles from the
project area (Schwartz, 1995). Cold winter water temperatures will probably
keep the species from overwintering in the project area. Foods which are used
by the manatee in North Carolina are unknown. In Florida, their diet consists
primarily of vascular plants. Project maintenance will involve no dredging of or
disposal near submerged grass beds and minimal change to the physical habitat
of the estuary. Overall estuarine and nearshore productivity should remain
unchanged throughout the project area. Therefore, potential food sources for the
manatee should not be affected.
The dredging equipment used for maintenance of the project is slow
moving and the crew is on constant watch due to the narrow channels in which
the vessels are operating. In the rare event that a manatee is observed by the
crew, dredging operations will stop until the manatee leaves the area.
Therefore, since the occurrence of a manatee is rare, the potential food source
will not be affected, and dredging operations will stop if a manatee is observed
in the area, the proposed action will not affect the manatee.
All other species under jurisdiction of the USFWS are terrestrial and the
proposed action will not impact terrestrial habitats. Therefore, no affect is
anticipated on such species.
4.04 Development and Economic Justification. As indicated in USACE
1995a, "pressure for waterfront development will continue with or without the
inlet as will the desire for increased dock space." Such development has
continued in the Sealevel and Atlantic areas. Although some of the proposed
development may be partially based on the presence of Drum Inlet, justification
for the maintenance of the inlet was not based on such development. As
indicated in USACE, 1995a, justification was based solely on cost reduction to
the existing commercial fishing fleet.
The increased frequency of maintenance of the connecting channel will
not alter the economic justification of the project due to the efficiency of the
sidecast dredge and the CURRITUCK. Maintenance by the sidecast dredge and
the CURRITUCK are about $2.00 and $1.60 per cubic yard of sand,
respectively. Economic justification for maintenance of the connecting channel
was based on using a hydraulic pipeline dredge with disposal on the beaches of
Core Banks. Such maintenance would cost about $5.00 per cubic yard.
4.05 Inlet Stability. The USACE, 1995a, indicated that Drum Inlet has
matured from its formative stage, and natural conditions such as inlet migration
"will not prevent the maintenance of a navigable channel across the ocean bar
9
or through the interior channels." This is still the case. As indicated above,
maintenance frequency will be greater than initially anticipated, but with the
additional alternatives of using the CURRITUCK and sidecast dredges, the inlet
and connecting channel should remain open indefinitely.
5.00 COORDINATION
Representatives from the agencies listed below were contacted regarding
the proposed action and preparation of this EA. Representatives from these
agencies were involved in the April 22, 1997, field trip regarding discharge from
the sidecast dredge FRY in the connecting channel at Drum Inlet. The purpose
of the April trip was to familiarize the agencies with the operations of a sidecast
dredge and to monitor the discharge from the dredge.
North Carolina Division of Coastal Management
North Carolina Division of Water Quality
North Carolina Division of Marine Fisheries
North Carolina Wildlife Resources Commission*
U.S. Fish and Wildlife Service
National Marine Fisheries Service
U.S. Environmental Protection Agency*
* Agencies contacted, but were not able to attend the field trip.
6.00 CONSISTENCY DETERMINATION FOR NORTH CAROLINA COASTAL
MANAGEMENT PROGRAM
Based on the information presented above, the proposed action is
consistent with the Carteret County 1991 Land Use Plan Update and the Coastal
Management Program of the State of North Carolina, to the maximum extent
practicable.
7.00 LIST OF RECIPIENTS
This EA is being circulated for a 30-day review to the following agencies
and individuals.
Federal Agencies
U.S. Environmental Protection Agency
Forest Service, USDA
10
Federal Agencies (cont'd)
U.S. Department of Housing and Urban Development
Advisory Council on Historic Preservation
National Oceanic and Atmospheric Administration
Center for Environmental Health
National Marine Fisheries Service
U.S. Department of Interior
U.S. Fish and Wildlife Service
Fifth Coast Guard District
Federal Highway Administration
Soil Conservation Service, USDA
U.S. Naval Port Control Office
U.S. Department of Energy
United States Coast Guard
Postmasters
State Agencies
North Carolina Division of Coastal Management
North Carolina Division of Environmental Management
North Carolina Division of Marine Fisheries
North Carolina Department of Environment, Health, and
Natural Resources
State Clearinghouse
Libraries
UNC-Chapel Hill Library
Librarian, North Carolina Environmental Resources Library
UNC-Wilmington Library
State Library of North Carolina
Duke University Library
East Carolina University - Joyner Library
Elected Officials
All U.S. Representatives and Senators for North Carolina
Honorable Bruce Ethridge
Honorable Paul Tyndall
Honorable G. Malcolm Fulcher, Jr.
Chairman, Carteret County Commissioners
Mayors
11
Local Agencies
North Carolina Council of Governments Region P
Carteret County Development Council
Morehead City Building Inspector
Conservation Groups
Conservation Council of North Carolina
North Carolina Environmental Defense Fund
Sierra Club
National Audubon Society
National Wildlife Federation
North Carolina Coastal Federation
North Carolina Wildlife Federation
Carteret County Crossroads
Izaac Walton League
Col leges/Universities
UNC Institute of Marine Science
Duke University Department of Geology
Cape Fear Community College
Companies and Individuals
Carteret-Craven EMC
Carteret County News-Times
Morehead City Shipping Co.
Williams and Haywood, Inc.
T.D. Eure Construction Co.
Wilmington Shipping Company
Sailcraft, Inc.
Texasgulf, Inc.
Great Lakes Dredge and Dock Company
Stevens Towing Company
Stroud Engineering
Timber and Land Management
Aviation Fuel Terminals
George Davenport
Grady Davis
John Hooten
T. O. Talton
12
Companies and Individuals (cont'd)
Don Taylor
R. T. Jones
Luther Smith and Son
Lloyd Wood
Alex Malpass
Galvin Mason
R. W. Chambers
John Fussel
Frank Hatsel
Walter Gentry
Haywood Weeks
William Whaley
Anne McCrary
Vince Bellis
Ray Brandi
Orrin Pilkey
Claude Brown
W. D. Aman
8.00 POINT OF CONTACT
Any comments or questions regarding this EA should be addressed to
Mr. Frank Yelverton, Environmental Resources Section, U.S. Army Corps of
Engineers, Wilmington District, PO Box 1890, Wilmington, North Carolina
28402-1890. Telephone contact is 910-251-4640.
9.00 ENVIRONMENTAL COMMITMENTS
For the first 2 years of maintenance, the shoals enlarged by the sidecast
dredge will be monitored annually or after each dredging event, whichever is
more frequent. Monitoring will include change in elevation and areal extent of
the shoals and establishment of seagrass beds. Monitoring results will be
coordinated with all interested parties. When available, use of the CURRITUCK
is preferred versus use of a sidecast dredge for removal of shoals in the
connecting channel.
13
10.00 REFERENCES
Moser, M. L. and S. W. Ross. 1993. Distribution and Movements of Shortnose
Sturgeon (Acipenser brevirostrum) and Other Anadromous Fishes of the
Lower Cape Fear River, North Carolina. Final Report to the U.S. Army Corps
of Engineers; Wilmington District, May 1993. 112 pp.
National Marine Fisheries Service. 1991. Biological Opinion, Dredging of
Channels in the Southeastern United States from North Carolina Through
Cape Canaveral, Florida. November 25, 1991.
N.C. Division of Marine Fisheries. 1997. Mike Marshall, personal
communication.
Schwartz, F.J. 1995. Florida Manatees, Trichechus manatus (Sirenia
Trichechidae), in North Carolina 1919-1994. Brimleyana No. 22:53-60.
June 1995.
U.S. Army Corps of Engineers, Wilmington District. 1995a. Environmental
Assessment, Maintenance of Drum Inlet, Carteret County, North Carolina.
Environmental Resources Section, January 1995.
U.S. Army Corps of Engineers, Wilmington District. 1995b. Biological
Assessment on findings of may affect on piping plover and seabeach
amaranth by the maintenance of Drum Inlet. Environmental Resources
Section. May 2, 1995.
U.S. Fish and Wildlife Service. 1995. Biological Opinion of the effects on the
Federally-threatened piping plover and seabeach amaranth by the
maintenance of Drum Inlet. Raleigh Field Office. June 30, 1995.
11.00 FINDING
The proposed action should not significantly affect the quality of the
human environment; therefore, an Environmental Impact Statement will probably
not be required. If this opinion is upheld following circulation of this EA, a
Finding of No Significant Impact (FONSI) will be signed and circulated.
14
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Table 3. Shoals Enlarged by Sidecast Dredging at Drum Inlet, NC, Spring 1997
Maximum Elevation (feet)
Above MLW
Average Elevation (feet)
Above MLW
Area (acres)
Above MHW
Area (acres)
Above MLW
Decrease (May-July)
% Decrease
Volume of sand (cubic yards)
Above MLW
Decrease (May-July)
% Decrease
SHOALS ENLARGED ADJACENT TO CONNECTING CHANNEL
May 20, 1997 Survey July 22, 1997 Survey
2.5 1.3
1.10
0.38
5.41
0.68
0.00
3.87
1.54
28%
9,360
4,189
5,171
55%
MLW - mean low water
MHW - mean high water (+ 2 feet MLW)
N420000
1417500
N415000
N4126M
N410000
N407600
FIGURE I.
SEAGRASS BEDS ON 1997 PHOTOGRAPHY
AT DRUM INLET, NC
SCALE: 1" = 2000'-?
IPF 1996 GRASS BEDS
1997 GRASS BEDS
Feet
2000 0 2000 4000
GRID BASED ON NORTH CAROLINA STATE PLANE 1NAD83) °RODOfOC'"sa 'E6p''
YRUmmm Hoffm MROlH4 BT:
DATE OF PHOTOGRAPHY: MAY 17.1997
1997 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY AMERICAN GEOGRAPHIC DATA INC.
5710 OLEANDER DRIVE SUITE 108
DATED MAY 17, 1997 WILMINGTON. NC 28403
(9101392-1496
1996 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY
DATED MAY 23, 1996
N420000
14417500
N415000
N412SOO
N410000
N40750C
E27975W E2800000 E2802500 E2805000 E28075W E2810000
ATTACHMENT A
SECTION 404(B)(1) (PUBLIC LAW 95-217) EVALUATION
Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina
Evaluation of Section 404(b)(1) Guidelines
40 CFR 230
1. Review of Compliance (230.10(a)-(d))
Review of the NEPA Document indicates:
a. The discharge represents the least
environmentally damaging practicable
alternative and if in a special aquatic
site, the activity associated with the
discharge must have direct access or
proximity to, or be located in the
aquatic ecosystem to fulfill its basic
purpose (if no, see section 2 and NEPA
document);
b. The activity does not: 1) violate
applicable State water quality
standards or effluent standards
prohibited under Section 307 of the
CWA; 2) jeopardize the existence of
federally listed endangered or
threatened species or their habitat;
and 3) violate requirements of any
federally designated marine sanctuary
(if no, see section 2b and check
responses from resource and water
quality certifying agencies);
C. The activity will not cause or
contribute to significant degradation
of waters of the U.S. including adverse
effects on human health, life stages of
organisms dependent on the aquatic
ecosystem, ecosystem diversity,
productivity and stability, and
recreational, aesthetic, and
economic values (if no, see section
2);
d. Appropriate and practicable steps have
been taken to minimize potential
adverse impacts of the discharge on
the aquatic ecosystem
(if no, see section 5).
Proceed to Section 2
*, 1, 2/ See page A-6
Preliminary 1/ Final 2/
YESI 1 NOI 1* YESIXI NO1 I
YESI 1 NOI I* YESIXI N011
YESI 1 NO1 I* YESIXI N01-1
YESI 1 NOI I* YESIXI N011
A-1
2. Technical Evaluation Factors (Subparts C-F)
a. Physical and Chemical Characteristics
of the Aquatic Ecosystem (Subpart C)
(1) Substrate impacts.
(2) Suspended particulates/turbidity
impacts.
(3) Water column impacts.
(4) Alteration of current patterns
and water circulation.
(5) Alteration of normal water
fluctuations/hydroperiod.
(6) Alteration of salinity
gradients.
b. Biological Characteristics of the
Aquatic Ecosystem (Subpart D)
Not Signifi- Signifi-
N/A cant cant*
I I X I I
I I I I
i I X I I
I I X I I
I I I I
I I X i I
I I I I
I I X I I
I i I I
I I X I I
(1) Effect on threatened/endangered I I I I
species and their habitat. I I X I I
(2) Effect on the aquatic food web. I I X I I
(3) Effect on other wildlife (mammals, I I I I
birds, reptiles, and amphibians). ? I X I I
C. Special Aquatic Sites (Subpart E)
(1) Sanctuaries and refuges. I X I I I
(2) Wetlands. I X I I I
(3) Mud flats. I X I I I
(4) Vegetated shallows. I X I I I
(5) Coral reefs. I X I I I
(6) Riffle and pool complexes. I X I I I
d. Human Use Characteristics (Subpart F)
(1) Effects on municipal and private I I I I
water supplies. I X I I I
(2) Recreational and commercial I I I I
fisheries impacts. I I X I I
(3) Effects on water-related recreation.) I X I I
(4) Aesthetic impacts. I I X I
(5) Effects on parks, national and I I I I
historical monuments, national I l I I
seashores, wilderness areas, I I I I
research sites, and similar I I I I
preserves. I X_I__ I I
Remarks: Where a mark is placed under
the significant category, preparer add
explanation below.
Proceed to Section 3
*See page A-6
A-2
3. Evaluation of Dredged or Fill Material (Subpart G) 3/
a. The following information has been
considered in evaluating the biological
availability of possible contaminants in
dredged or fill material. (Mark only
those appropriate.)
(1) Physical characteristics . . . . . . . . . . . . . . . . . .IXI
(2) Hydrography in relation to
known or anticipated _
sources of contaminants . . . . . . . . . . . . . . . . . . . 1 XI
I
(3) Results from previous
testing of the material
or similar material in
the vicinity of the project . . . . . . . . . . . . . . . . . 1 X I
(4) Known, significant sources of
persistent pesticides from _
land runoff or percolation . . . . . . . . . . . . . . . . . . 11
(5) Spill records for petroleum
products or designated
(Section 311 of CWA)
hazardous substances . . . . . . . . . . . . . . . . . . . . 1 1
(6) Other public records of
significant introduction of
contaminants from industries,
municipalities, or other _
sources . . . . . . . . . . . . . . . . . . . . . . . . . . .I I
(7) Known existence of substantial
material deposits of
substances which could be
released in harmful quantities
to the aquatic environment by _
man-induced discharge activities . . . . . . . . . . . . . I I
(8) Other sources (specify) . . . . . . . . . . . . . . . .. . . I I
List appropriate references.
EA "Maintenance of Drum Inlet, Carteret County,
North Carolina," dated January 1995
EA "Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina," dated August 1997
b. An evaluation of the appropriate information in 3a
above indicates that there is reason to believe the
proposed dredge or fill material is not a carrier of
contaminants, or that levels of contaminants are sub-
stantively similar at extraction and disposal sites and
not likely to result in degradation of the disposal site.
The material meets the testing exclusion criteria. YES 1X1 NO 11*
Proceed to Section 4
3/, see page A-6
A-3
4. Disposal Site Determinations (230.11(f)).
a. The following factors as appropriate,
have been considered in evaluating the
disposal site.
(1) Depth of water at disposal site . . . . . . . . . . . . IXI
(2) Current velocity, direction, and
variability at disposal site . . . . . . . . . . . . . 1X1
(3) Degree of turbulence . . . . . . . . . . . . . . . . . 1 X I
(4) Water column stratification . . . . . . . . . . . . . . IXI
(5) Discharge vessel speed and
direction . . . . . . . . . . . . .. . . . . . . . . . _
1 X I
(6) Rate of discharge . . . . . . . . . . . . . . . . . . . IXI
(7) Dredged material characteristics
(constituents, amount and type _
of material, settling velocities). . . . . . . . . . .IXI
(8) Number of discharges per unit of _
time . . . . . . . . . . . . . . . . . . . . . . . . . 1 X I
(9) Other factors affecting rates and
patterns of mixing (specify)
List appropriate references.
EA "Maintenance of Drum Inlet, Carteret County,
North Carolina," dated January 1995
EA "Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina," dated August 1997
b. An evaluation of the appropriate factors in
4a above indicates that the disposal site
and/or size of mixing zone are acceptable . . . .YES IXI NO 11*
5. Actions to Minimize Adverse Effects (Subpart H).
All appropriate and practicable steps have been taken,
through application of recommendations of 230.70-230.77,
to ensure minimal adverse effects of the proposed
discharge. List actions taken. YES IXI NO I I*
See sections 4.01 through 4.03 and 9.00 of the 1997 EA.
Return to section 1 for final stage of compliance review. See also
note 3/, page A-6.
*See page A-6
A-4
M
6. Factual Determinations (230.11).
A review of appropriate information as identified in
items 2-5 above indicates that there is minimal
potential for short- or long-term environmental
effects of the proposed discharge as related to:
a. Physical substrate at the disposal site
(review sections 2a, 3, 4, and 5). YES IXI NO I I*
b. Water circulation, fluctuation, and salinity
(review sections 2a, 3, 4, and 5). YES 1XI NO 1-1*
C. Suspended particulates/turbidity
(review sections 2a, 3, 4, and 5). _ _
YES IXI NO 11*
d. Contaminant availability
(review sections 2a, 3, and 4). YES 1XI NO 1-1*
e. Aquatic ecosystem structure and function YES IXI NO I
1*
(review sections 2b and c, 3, and 5). _
f. Disposal site
(review sections 2, 4, and 5). YES 1XI NO 1-1*
g. Cumulative impact on the aquatic
ecosystem. YES IXI NO 1-1*
h. Secondary impacts on the aquatic
ecosystem. YES 1XI NO 1-1*
7. Findings.
a. The proposed disposal site for discharge of
dredged or fill material complies with the
Section 404(b)(1) guidelines . . . . . . . . . . . _
. . . . . .IXI
b. The proposed disposal site for discharge of
dredged or fill material complies with the
Section 404(b)(1) guidelines with the _
inclusion of the following conditions: I I
*See page A-6
A-5
C. The proposed disposal site for discharge of
dredged or fill material does not comply with
the Section 404(b)(1) guidelines for the
following reasons(s):
(1) There is a less damaging practicable alternative. . . . . I
(2) The proposed discharge will result in significant _
degradation of the aquatic ecosystem . . . . . . . . . . i
(3) The proposed discharge does not include all
practicable and appropriate measures to minimize _
potential harm to the aquatic ecosystem . . . . . . . . . I
8.
C. E. Shu rd,
Acting Chief, Engineering
and Planning Division
Date: p 7
*A negative, significant, or unknown response indicates that the permit application may
not be in compliance with the Section 404(b)(1) Guidelines.
1/ Negative responses to three or more of the compliance criteria at this stage
indicate that the proposed projects may not be evaluated using this "short form
procedure." Care should be used in assessing pertinent portions of the technical
information of items 2 a-d, before completing the final review of compliance.
2/ Negative response to one of the compliance criteria at this stage indicates that the
proposed project does not comply with the guidelines. If the economics of navigation
and anchorage of Section 404(b)(2) are to be evaluated in the decision-making process,
the "short form evaluation process is inappropriate."
3/ If the dredged or fill material cannot be excluded from individual testing, the
"short-form" evaluation process is inappropriate.
I
A-6
September 22, 1997
MEMORANDUM
TO: Michelle Suverkrubbe
THROUGH: John Dome
FROM: Eric Fleek?
RE: Drum Inlet Dredging
The Division of Water Quality has reviewed the Environmental Assessment for the dredging of Drum Inlet.
Based on this review, DWQ will likely recommend the following conditions be placed on the 401:
1) If dredging occurs in areas of less than 90% sand while dredging Tangent A in the vicinity of
E2800000 and N418000, monitoring of turbidity levels in the SAV to the southeast should be carried
out to determine the lateral extent of the sediment plume from outside the channel axis environs.
Monitoring will be for surface levels (i.e. 1-foot depth) of turbidity.
2) If turbidity levels at this SAV bed exceed 25 NTUSs, dredging operations shall be suspended until it
can be demonstrated that these dredging activities can be continued without violations of this standard.
If you have any questions regarding this matter please feel free to call Mr. Eric Fleek or myself at
(919) 733-1786.
R. Dorsey
T Quality Certificati Program
Cc: Steve Benton, Division of Coastal Management
Frank Yelverton, USACOE
Michelle Suverkrubbe, Division of Water Quality
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
A IT;W?
40&
C) EHNR
Division of Water Quality
Environmental Sciences Branch
4401 Reedy Creek Road
Raleigh, N.C. 27607
FAX:(919) 733-9959
Date 1? ? (-/
I FAX TO: r ( ( ((r 5 / ()C/r/L I FAX NUMBER: 7-2, I I-q 5
FROM:r? c (?` CC
PHONE:
NO. OF PAGES INCLUDING THIS SHEET: ?;Z-
cqrf-
C' irk)
r- -/-, ?' i-?A a V
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Environmental Sciences Branch 4401 Reedy Creek Road Raleigh, North Carolina 27607
Telephone 919-733-9960 FAX # 733-9959
An Equal Opportunity Affirmative Action Employer 50% recycled/10% post consumer paper
State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Coastal Management
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
Roger N. Schecter, Director
09109/97
Mr. John R. Dorney
NC DEN&NR
Division of Water Quality
P.O. Box 27687
_ _.._ , . .
Raleigh, NC-27611
REFERENCE: CD97-33 County: Carteret
Applicant/Sponsor: U.S. Army Corps of Engineers
EA: Hopper Dredge with Overflow or Sidecast Dredging, Drum Inlet
Dear Mr. Dorney:,
The attached Consistency Determination, dated 08129197
describing a proposed Federal Activity is being circulated to
State agencies for comments concerning the proposal's consistency
with the North Carolina Coastal Management Program.
Please indicate your viewpoint on the proposal and return this
L
form to me before 09123197 4Stee ly,
n B. Ben ton
Consistency Coordinator
REPLY T 's o ' e objects to the project as proposed.
Comments on this project are attached.
This office supports the project proposa
No comment.
S3JN3I?Sl ?? .: ?vu??vui t7N?
S
1661
n:-4A
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone 919-733-2293
An Equal Opportunity Affirmative Action Employer 50% Recycled/ 10% Post-Consumer Paper
Environmental 4P0 riewracking Sheet DWQ - Water Quality Section
MEM
TO. Env. Scienc
* Wetlands
O John I
O Cyndi
IKEric C
O
* Bio. Resources, Habitat, End. Species
O Trish MacPherson
O Kathy Herring (forest/oRwmQw)
O
* Toxicology
O Larry Ausley
O
Planning Branch (Archdale - 6th)
O
FROM: Michelle Suverkrubbe, Planning Branch
I (Archdale 9th)
E, NPDES
4ate
:E, Stormwater
. _ am Assess. (modeling)
O Carla Sanderson, Rapid Assess.
O
Operations Branch (Archdale 7th)
O Kent Wiggins, Facility Assessment
O Tom Poe, Pretreatment
O Lisa Martin, Water Supply Watershed
Regional Water Quality Supervisors
O Asheville O Mooresville O Washington
O Fayetteville • O Raleigh O Wilmington
O Winston-Salem
Attached is a copy of the above document. Subject to the requirements of the North Carolina
Environmental Policy Act, you are being asked to review the document for potential significant impacts
to the environment, especially pertinent to your jurisdiction, level of expertise or permit authority. Please
check the appropriate box below and return this form to me along with your written comments, if any, by
the date indicated.
Thank you for your assistance. Suggestions for streamlining and expediting this process are greatly
appreciated !
Notes:
I can be reached at:
phone: (919) 733-5083, ext. 567 fax: (919) 715-5637 e-mail: michelle@dem.ehnr.state.nc.us
Post-it® Fax Note 7671 Date -11 Z- pages 10.
Z-
To Al iQWLQ C JVtI?°(k/?rLe From i L .
-fC
Co./Dept. ®('V I
Co. r1 / l1
?
J W
Phone # Phone
#
I Fax # I I l' I I ?? ?tC /? Fax #
misAcircmemo - mac version
14V
DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
P.O. BOX 1890
WILMINGTON, NORTH CAROLINA 28402-1890
IN REPLY REFER TO August 29, 1997
Environmental Resources Section RECEIVED
"OASTAL MANAGEMENT
Dear Sir or Madam:
Enclosed for your review and comments is one copy of the
Environmental Assessment. Use of the Hopper Dredge CURRITUCK with
Overflow or Sidecast Dredge as Additional Maintenance Dredging
Methods for Drum Inlet, Carteret County, North Carolina, dated August
1997. The environmental assessment (EA) has been prepared in
accordance with the Council on Environmental Quality (40 CFR 1500-
1508) and the U.S. Army Corps of Engineers regulations (33 CFR 230) for
implementing the National Environmental Policy Act of 1969, as
amended.
The primary purpose of this EA is to discuss the need for and
impacts of using the hopper dredge CURRITUCK with overflow and
sidecast dredge as additional maintenance dredging methods for the
Drum Inlet connecting channel. As the EA indicates, these additional
maintenance dredging methods should not adversely impact the
environment.
Please provide any comments you may have by September 30,
1997. If you have any questions concerning this matter, please contact
Mr. Frank Yelverton, Environmental Resources Section, at (910) 251-
4640.
Sincerely,
C. E. Sh ford, Jr., P.E.
Acting Chief, Engineering
and Planning Division
Enclosure
S
US ARMY CORPS
OF ENGINEERS
Wilmington District
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
-7 15 -5637
I AUGUST 1997
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
TABLE OF CONTENTS
Heading Page No.
1.00 PROJECT DESCRIPTION .....................................................................................1
2.00 PURPOSE AND NEED .........................................................................................1
3.00 DREDGING AND DISPOSAL METHODS ..............................................................2
3.01 Hydraulic Pipeline Dredge ..........................................................................2
3.02 Sidecast Dredges and the Hopper Dredge CURRITUCK ...........................3
4.00 ENVIRONMENTAL EFFECTS ...............................................................................4
4.01 Water Quality ..............................................................................................4
4.02 Aquatic Resources .....................................................................................5
4.03 Endangered Species ..................................................................................8
4.04 Development and Economic Justification ...................................................9
4.05 Inlet Stability ...............................................................................................9
5.00 COORDINATION ..................................................................................................10
6.00 CONSISTENCY DETERMINATION FOR NORTH CAROLINA COASTAL
MANAGEMENT PROGRAM ............................................................................10
7.00 LIST OF RECIPIENTS .........................................................................................10
8.00 POINT OF CONTACT ..........................................................................................13
9.00 ENVIRONMENTAL COMMITMENTS ...................................................................13
10.00 REFERENCES ...................................................................................................14
11.00 FINDING .............................................................................................................14
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
TABLE OF CONTENTS (cont'd)
TABLES
(Follows Page 14)
TABLE 1. Sidecast Dredge Discharge in Tangent A, Drum Inlet, North Carolina.
TABLE 2. Sidecast Dredge Discharge in Tangent B, Drum Inlet, North Carolina.
TABLE 3. Shoals Enlarged by Sidecast Dredging at Drum Inlet, North Carolina.
FIGURES
(Follows Tables)
FIGURE 1. Seagrass Beds on 1997 Photography at Drum Inlet, North Carolina.
ATTACHMENTS
(Follows Tables and Figures)
ATTACHMENT A. Evaluation of Section 404(b)(1) Guidelines.
ENVIRONMENTAL ASSESSMENT
USE OF THE HOPPER DREDGE CURRITUCK
WITH OVERFLOW OR SIDECAST DREDGE
AS ADDITIONAL MAINTENANCE DREDGING METHODS
FOR DRUM INLET
CARTERET COUNTY, NORTH CAROLINA
August 1997
1.00 PROJECT DESCRIPTION
The maintenance of Drum Inlet was discussed in detail in the
environmental assessment (EA) dated January 1995, and letter amendment
dated April 28, 1995 (U.S. Army Corps of Engineers (USACE), 1995a).
According to that EA, maintenance of the bar channel (inlet area, seaward of
Tangent C, figure 1) would be by sidecast dredge or the hopper dredge
CURRITUCK and maintenance of the connecting channel M , WA1Ft1
would be by hydraulic pipeline dredge with disposal on the beach of Core
Banks. ^'Aadusna in
Maintenance frequency of the connecting channel was anticipated to be
every 2-3 years with a volume of 100,000 cubic yards. However with experience
following construction, maintenance in the connecting channel will probably be
every 3-6 months with 30,000-90,000 cubic yards of sand removed during each
event. Because of the increased frequency with relatively small volumes the
sidecast dredges and the CURRITUCK need to be added as maintenance
options for the connecting channel. Disposal by the sidecast dredge would be
either north or south of the channel depending on which way the predominant
current is flowing (generally north during the warmer months and south during
the cooler months). The CURRITUCK would dispose of the sand in the
nearshore ocean area.
2.00 PURPOSE AND NEED
The purpose of this EA is to discuss the need for and impacts of using a
sidecast dredge or the hopper dredge CURRITUCK with overflow as additional
maintenance dredging methods for the Drum Inlet connecting channel. This EA
is also intended to amend the EA for the Maintenance of Drum Inlet, Carteret
County, North Carolina (USACE, 1995a) to include these additional
maintenance methods.
The following reasons show why these additional maintenance methods
are needed:
a. Maintenance frequency of the connecting channel is greater than
anticipated.
b. Due to recreational fishing and sea turtle and colonial waterbird
nesting, hydraulic pipeline dredging with disposal on the beach of Core Banks is
permitted from December 15 to March 31. Shoals block the connecting channel
at other times of the year.
c. Mobilizing a hydraulic pipeline dredge with 1-2 miles of pipeline to the
beach disposal area for small shoals is not practical.
The following are in addition to the indicated need:
a. Sidecast dredging and hopper dredging with overflow in the connecting
channel should not adversely impact the environment.
b. The increased frequency of maintenance of the connecting channel will
not alter the economic justification of the project, due to the efficiency of the
sidecast dredge and the CURRITUCK.
3.00 DREDGING AND DISPOSAL METHODS
The existing and proposed dredging and disposal methods in the
connecting channel are described below:
3.01 Hydraulic Pipeline Dredge. According to USACE, 1995a, only
maintenance dredging in the connecting channel is allowed by hydraulic pipeline
dredge. The dredged material would be pumped to the beaches of Core Banks
north or south of the inlet and placed below the limit of the wave uprush zone to
minimize alterations and impacts to the upland portion of the beach. The wave
uprush zone is the part of the beach wetted by the normal wave uprush. The
beach is owned by the National Park Service, Cape Lookout National Seashore
(Service), and a Special Use Permit is required from the Service prior to any
disposal activities. Maintenance efforts in this channel with a hydraulic pipeline
dredge were anticipated to involve dredging approximately 100,000 cubic yards
every 2-3 years. This maintenance would be done at the same time as the
maintenance of the waterway in Core Sound in order to eliminate the high cost
for separate mobilization.
2
Hydraulic pipeline dredging is restricted to the connecting channel
because seaward of Tangent C (figure 1) the wave environment is too intense
for conventional pipeline dredge operations. The channel dimensions are too
restrictive for use of an ocean-certified pipeline dredge.
Initial dredging of the connecting channel was completed by hydraulic
pipeline dredge in March 1997. After the dredge left the area, the channel
began to rapidly shoal. Therefore under emergency procedures (Memorandum
of Agreement [MOA] between the Wilmington District and the North Carolina
Department of Environment, Health, and Natural Resources, signed December
1986), the sidecast dredge FRY removed about 88,000 cubic yards of sand from
the connecting channel between April 11 and 30, 1997. This material was
deposited adjacent to the north side of Tangents A and B (figure 1), since north
was the predominant direction the currents were flowing. Emergency dredging
was again required under the MOA in early August 1997, just prior to publication
of this EA. The CURRITUCK was to remove about 50,000 cubic yards from the
connecting channel with disposal in the nearshore ocean waters.
3.02 Sidecast Dredges and the Hopper Dredge CURRITUCK. Sidecast
dredging with disposal adjacent to the channel is currently only allowed for
maintenance of the bar channel with disposal adjacent to the channel. Hopper
dredging with the CURRITUCK is currently only allowed for maintenance of the
bar channel with disposal in nearshore ocean waters.
A sidecast dredge has two drag arms (one on each side) that "vacuum" the
sediment as the arms drag along the bottom. The sediment is pumped through a
discharge pipe that is above the water surface and perpendicular to the dredge.
The discharge pipe extends about 60 feet beyond the side of the dredge. This
pipe distance and force from the pumps generally results in the sediment being
deposited 85 to 100 feet from the dredge. The sediment is discharged on the
side of the channel where the predominant currents would tend to move the
sediment away from the channel. The U.S. Army Corps of Engineers has three
sidecast dredges (all operated by the Wilmington District), and one would
generally be available to maintain Drum Inlet.
The CURRITUCK has drag arms similar to a sidecast dredge, but the
sediment is pumped into the dredge's hopper. The water in the hopper is
overflowed to provide an economic load of sand, since the dredged slurry
entering the hopper contains about 20 percent sand and 80 percent water.
Once the hopper is full of sand (about 300 cubic yards), the sediment is taken to
nearshore ocean waters (normally -6 to -10 feet mean low water [m.l.w.]) where
the split hull hopper is opened and the sediments are deposited. The
CURRITUCK is the only small hopper dredge the U.S. Army Corps of Engineers
has (operated by the Wilmington District) that is capable of maintaining Drum
3
Inlet, and commercial hopper dredges as small as the CURRITUCK do not exist.
Due to the high demand for this dredge outside of the District, it is only available
in North Carolina about 6 months each year (August - October and December-
February). When available, the CURRITUCK will be used, instead of a sidecast
dredge, for removal of shoals in the connecting channel.
The use of the sidecast dredge and the CURRITUCK will probably be
needed for maintenance of the connecting channel every 3-6 months year-
round. As detailed below, these maintenance alternatives and anticipated
frequency should have minimal impact on the environment.
4.00 ENVIRONMENTAL EFFECTS
The Drum Inlet environment is discussed in detail in USACE, 1995a. This
EA will primarily add information related to the monitoring data collected
April 22, 1997, while the sidecast dredge FRY was operating under emergency
procedures in the Drum Inlet connecting channel.
4.01 Water Quality. The North Carolina water quality classification
assigned to the Drum Inlet area (White Oak Basin) is SA/ORW. SA waters are
suitable for commercial shellfishing and all other tidal salt water uses including
primary and secondary recreation, and fish propagation. ORW (Outstanding
Resource Waters) are unique and special waters of exceptional state or national
recreation or ecological significance which require special protection to maintain
existing uses. The North Carolina Division of Water Quality (NCDWQ) standard
for turbidity for SA/ORW is 25 NTU's. There is no NCDWQ suspended sediment
standard for the area.
Two discharge events from the sidecast dredge FRY were monitored in the
connecting channel where the dredge was working on April 22, 1997. The first
discharge monitored on the dredged material was from the western to the
eastern end of Tangent A. The sediments in Tangent A are about 94 percent
sand and represents the lowest percentage of sand in the connecting channel
since Tangent A is the greatest distance from the inlet. Table 1 generally
indicates a major reduction in suspended sediment concentration and turbidity
with distance from the dredge (the low value at the surface 100 feet from the
discharge pipe was probably due to sampling a clear water pocket). Both
parameters neared background values at 1,500 feet from the dredge. Samples
were not taken beyond 1,500 feet because the turbidity plume associated with
the discharge was no longer visibly evident.
The surface and bottom background turbidity values measured April 22,
1997, were both below 25 NTUs (6 and 14, respectively). At 1,500 feet from the
4
dredge during the discharge test, both the surface and bottom values were 25
NTUs or less (Table 1). This turbidity plume is generally confined to the near
channel area out to 1,500 feet since the dredge is steering into tidal currents
averaging about 1 knot.
The second discharge monitored on the dredged material was from the
eastern to western end of Tangent B. The sediments in Tangent B are about 95
percent sand and contain a higher percentage of sand than Tangent A since
Tangent B is closer to the inlet. Table 2 indicates a general reduction in
suspended sediment concentration and turbidity with distance from the dredge.
Both parameters neared background values at 2,000 feet from the dredge.
Samples were not taken beyond 2,000 feet because the turbidity plume
associated with the discharge was no longer visibly evident.
The surface and bottom background turbidity values for the second
discharge were also both below 25 NTUs (9 and 13, respectively). At 2,000 feet
from the dredge during the discharge test, both the surface and bottom values
were less than 25 NTUs (table 2). As with the first test, the turbidity plume is
generally confined to the near channel area out to 2,000 feet since the dredge is
steering into tidal currents averaging about 1 knot.
Monitoring of turbidity and suspended solids levels in the overflow from the
CURRITUCK has not been performed. However, since the purpose of the
CURRITUCK is to retain sediment in the hopper, the turbidity and suspended
solids levels in the overflow should be less than that monitored for the sidecast
dredge FRY.
Based on the above information, the proposed action should not adversely
impact water quality.
The North Carolina Division of Water Quality will concurrently review this
EA and the U.S. Army Corps of Engineers' request for a Section 401 (P.L. 95-
217) Water Quality Certificate to authorize the work that may impact water
quality under the proposed action. Also, the Section 404(b)(1) evaluation for the
discharge of dredged material is included (Attachment A).
4.02 Aquatic Resources. The only changes to resources from the 1995
Drum Inlet EA (USACE, 1995a) are (1) the increased turbidity and suspended
solids levels associated with discharge from the sidecast dredge and overflow
from the CURRITUCK, and (2) enlarging existing shoals adjacent to the
channel where the sidecast dredge discharges and deposition in the near
shore ocean area by the CURRITUCK.
??Z?O() 00G 5
N 4-1 5`00C
Increased Turbidity and Suspended Solids. Levels. As indicated in
section 4.01, the increased turbidity and suspended solids levels associated with
discharge from the sidecast dredge return to background or near background
levels relatively close to the dredge. The dredges could perform maintenance
work at Drum Inlet for 2-4 weeks every 3-6 months, but when onsite the dredges
do not work continuously. The sidecast dredge usually operates 10 hours per
day (6:00 a.m. to 4:00 p.m.). The sidecast may dredge a shoal for 20-30
minutes, and take another 20-30 minutes to reposition the dredge at the
beginning of the shoal (vessel heads into the current to maintain steerage).
Considering repositioning time and run time to and from the dock at the
beginning and end of the 10-hour day, the dredge may be moving sediment on
an intermittent basis 4-5 hours per day.
The hopper dredge CURRITUCK also operates about 10 hours per day.
This vessel dredges an average of 20 minutes to load the hopper (about 300
cubic yards), but about 30-40 additional minutes are needed for a round trip to
the nearshore ocean disposal location. Considering round trip time to the ocean
and run time to and from the dock at the beginning and end of the 10-hour day,
the dredge may be moving sediment and overflowing the hopper on an
intermittent basis 3-4 hours per day.
Due to the low levels of turbidity and suspended solids, intermittent
occurrence, small relative area affected, and lack of primary nursery areas in the
vicinity, marine fishery resources should not be adversely affected.
Enlarging Existing Shoals and Deposition in the Nearshore Ocean
Area. All the sediment excavated by a sidecast dredge is deposited adjacent to
the channel where the predominant currents will tend to reduce return of the
sediments to the channel. For example, all the sediments removed by the
sidecast dredge FRY in April 1997 (87,649 cubic yards, 18 days of the period
April 11 - 30, 1997) were placed on the north side of the channel because the
predominant current was running north. According to the captain of the sidecast
dredge FRY, this deposition raised elevation of the shoals adjacent to the
channel up to 2-3 feet in a total of 3 areas adjacent to the north side of Tangents
A and B. The elevation change of the areas affected by the discharge can not
be accurately determined since a pre-dredging elevation survey was not taken
that included the existing shoaled areas adjacent to the channel.
Aerial photography was taken of the Drum Inlet area on February 16, 1997
(shortly after hydraulic pipeline dredging began in the connecting channel and
was still in Tangent A), and on May 17, 1997, after the emergency sidecast
dredging was complete. Comparison of the photography from these dates
indicates that the areas where the sidecast dredge deposited the sand were
6
existing shoals, with some of the area on the February photography appearing
intertidal. However, the May 17, 1997, photographs do appear to indicate more
intertidal areas adjacent to the north side of the channel than the February
photographs.
Extensive elevation surveys were performed on May 20 and July 22, 1997
(after emergency sidecast dredging), in the area within 300 feet of the north
edge of Tangents A and B. This data is summarized in table 3. In the area
surveyed on May 20, 1997, about 0.38 acres were 6 inches or less above mean
high water (m.h.w.), and 5.41 acres were above m.l.w. The rest of the area was
subtidal. As indicated above, some of this area was probably intertidal before
sidecast dredging began. The same area was again surveyed on July 22, 1997.
On July 22, 1997, no areas remained above m.h.w., and 3.87 acres were above
m.l.w. (intertidal). Between the May and July surveys, about 55 percent of the
volume of sand on the shoals was dispersed by wind waves and currents in the
open sound. Since this change occurred in about two months, establishing a
permanent area above m.h.w. should be precluded because of an anticipated
maintenance frequency of 3-6 months, and when available, the CURRITUCK will
be used, instead of a sidecast dredge, for removal of shoals in the connecting
channel.
However, these elevated areas could become permanent features. If so,
benthic resources in the shoals would be suppressed if sidecast dredging is
frequent. Nevertheless, these areas could provide some habitat enhancement
such as loafing and foraging areas for waterbirds, and seagrass beds could
establish on the leeward side of the shoals. This condition will be monitored for
at least the first 2 years of maintenance. Monitoring will include change in
elevation and areal extent of the shoals, and establishment of seagrass beds.
The Drum Inlet area is heavily used by commercial and recreational
fishermen. For example, the area is open to the mechanical harvest of clams
(North Carolina Division of Marine Fisheries [NCDMF], 1997). During each
dredging event, the areas where disposal occurs will be at least temporarily
unavailable (due to decreased water depth) for mechanical harvesting.
Excluded from the mechanic harvest area are oyster and clam leases and known
seagrass beds. No leases are located near the project area. Several leases are
located on the mainland near Atlantic, and one lease is located on the Core
Banks side about 6 miles south of Drum Inlet. Therefore, no leases will be
affected by the proposed action.
Based on seagrass mapping, no seagrasses are within 800 feet of the
channel alignment (figure 1). This mapping was based on May 23, 1996, and
7
May 17, 1997, aerial photography; and July 22, 1997, field verification of the
May 1997 photography. Due to the distance to the nearest grass beds, dredging
of the connecting channel by sidecast dredges or the hopper dredge
CURRITUCK should not impact these resources.
The CURRITUCK will dispose of up to 300 cubic yards of sand in the
nearshore (6-10 feet m.l.w.) ocean area during each dredging cycle (up to 10
times per 10-hour day). The sand disposed in the active wave environment will
quickly dissipate and should not appreciably affect the nearshore environment.
4.03 Endangered Species. The proposed action will not affect listed
species under the jurisdiction of the U.S. Fish and Wildlife Service (USFWS) or
the National Marine Fisheries Service (NMFS). Endangered species were
discussed in USACE, 1995a. That EA also discussed the year-round use of the
sidecast dredges and the hopper dredge CURRITUCK in the inlet. The May 2,
1995, Biological Assessment also discussed two species (piping plover and
seabeach amaranth) under the jurisdiction of the USFWS (USACE, 1995b). The
NMFS in their letter dated January 31, 1995, did not indicate impacts on listed
species, and the USFWS provided their Biological Opinion on June 30, 1995
(USFWS, 1995). This EA would extend the operation of the sidecast dredges
and the CURRITUCK year-round into the connecting channel as an additional
method of maintenance dredging.
The NMFS listed species have not changed since the 1995 EA. As
indicated in the 1995 EA for species under the NMFS jurisdiction, the operation
of sidecast dredges and the hopper dredge CURRITUCK are not believed
harmful to sea turtles because of the small size of the dragheads, slow speed of
the vessels, and the low suction levels (NMFS, 1991). None of the whales
should be impacted by the proposed action since all the dredging, disposing,
and maneuvering actions would be in the sound or close to the beach and in
shallow water. The shortnose sturgeon has been documented recently for the
Cape Fear River (Moser and Ross, 1993), but no other populations are known
from North Carolina. Therefore, species under the NMFS jurisdiction will not be
affected by the additional maintenance methods.
The only listed species change since the 1995 EA under the USFWS
jurisdiction that may occur in waters affected by the additional proposed
maintenance methods is the manatee (Trichechus manatus). The manatee is a
rare visitor to the area. All of the presently designated critical habitat is in
Florida. From 1919 to 1994 a total of 13 manatees had been observed in
Carteret County (an average of less than one every 5 years), with the most
observed in any year was two. The nearest observation to Drum Inlet was of a
8
single individual at Davis in September 1983 and 1993, about 10 miles from the
project area (Schwartz, 1995). Cold winter water temperatures will probably
keep the species from overwintering in the project area. Foods which are used
by the manatee in North Carolina are unknown. In Florida, their diet consists
primarily of vascular plants. Project maintenance will involve no dredging of or
disposal near submerged grass beds and minimal change to the physical habitat
of the estuary. Overall estuarine and nearshore productivity should remain
unchanged throughout the project area. Therefore, potential food sources for the
manatee should not be affected.
The dredging equipment used for maintenance of the project is slow
moving and the crew is on constant watch due to the narrow channels in which
the vessels are operating. In the rare event that a manatee is observed by the
crew, dredging operations will stop until the manatee leaves the area.
Therefore, since the occurrence of a manatee is rare, the potential food source
will not be affected, and dredging operations will stop if a manatee is observed
in the area, the proposed action will not affect the manatee.
All other species under jurisdiction of the USFWS are terrestrial and the
proposed action will not impact terrestrial habitats. Therefore, no affect is
anticipated on such species.
4.04 Development and Economic Justification. As indicated in USACE
1995a, "pressure for waterfront development will continue with or without the
inlet as will the desire for increased dock space." Such development has
continued in the Sealevel and Atlantic areas. Although some of the proposed
development may be partially based on the presence of Drum Inlet, justification
for the maintenance of the inlet was not based on such development. As
indicated in USACE, 1995a, justification was based solely on cost reduction to
the existing commercial fishing fleet.
The increased frequency of maintenance of the connecting channel will
not alter the economic justification of the project due to the efficiency of the
sidecast dredge and the CURRITUCK. Maintenance by the sidecast dredge and
the CURRITUCK are about $2.00 and $1.60 per cubic yard of sand,
respectively. Economic justification for maintenance of the connecting channel
was based on using a hydraulic pipeline dredge with disposal on the beaches of
Core Banks. Such maintenance would cost about $5.00 per cubic yard.
4.05 Inlet Stability. The USACE, 1995a, indicated that Drum Inlet has
matured from its formative stage, and natural conditions such as inlet migration
"will not prevent the maintenance of a navigable channel across the ocean bar
9
or through the interior channels." This is still the case. As indicated above,
maintenance frequency will be greater than initially anticipated, but with the
additional alternatives of using the CURRITUCK and sidecast dredges, the inlet
and connecting channel should remain open indefinitely.
5.00 COORDINATION
Representatives from the agencies listed below were contacted regarding
the proposed action and preparation of this EA. Representatives from these
agencies were involved in the April 22, 1997, field trip regarding discharge from
the sidecast dredge FRY in the connecting channel at Drum Inlet. The purpose
of the April trip was to familiarize the agencies with the operations of a sidecast
dredge and to monitor the discharge from the dredge.
North Carolina Division of Coastal Management
North Carolina Division of Water Quality
North Carolina Division of Marine Fisheries
North Carolina Wildlife Resources Commission*
U.S. Fish and Wildlife Service
National Marine Fisheries Service
U.S. Environmental Protection Agency*
* Agencies contacted, but were not able to attend the field trip.
6.00 CONSISTENCY DETERMINATION FOR NORTH CAROLINA COASTAL
MANAGEMENT PROGRAM
Based on the information presented above, the proposed action is
consistent with the Carteret County 1991 Land Use Plan Update and the Coastal
Management Program of the State of North Carolina, to the maximum extent
practicable.
7.00 LIST OF RECIPIENTS
This EA is being circulated for a 30-day review to the following agencies
and individuals.
Federal Agencies
U.S. Environmental Protection Agency
Forest Service, USDA
10
Federal Agencies (cont'd)
U.S. Department of Housing and Urban Development
Advisory Council on Historic Preservation
National Oceanic and Atmospheric Administration
Center for Environmental Health
National Marine Fisheries Service
U.S. Department of Interior
U.S. Fish and Wildlife Service
Fifth Coast Guard District
Federal Highway Administration
Soil Conservation Service, USDA
U.S. Naval Port Control Office
U.S. Department of Energy
United States Coast Guard
Postmasters
State Agencies
North Carolina Division of Coastal Management
North Carolina Division of Environmental Management
North Carolina Division of Marine Fisheries
North Carolina Department of Environment, Health, and
Natural Resources
State Clearinghouse
Libraries
UNC-Chapel Hill Library
Librarian, North Carolina Environmental Resources Library
UNC-Wilmington Library
State Library of North Carolina
Duke University Library
East Carolina University - Joyner Library
Elected Officials
All U.S. Representatives and Senators for North Carolina
Honorable Bruce Ethridge
Honorable Paul Tyndall
Honorable G. Malcolm Fulcher, Jr.
Chairman, Carteret County Commissioners
Mayors
11
Local Agencies
North Carolina Council of Governments Region P
Carteret County Development Council
Morehead City Building Inspector
Conservation Groups
Conservation Council of North Carolina
North Carolina Environmental Defense Fund
Sierra Club
National Audubon Society
National Wildlife Federation
North Carolina Coastal Federation
North Carolina Wildlife Federation
Carteret County Crossroads
Izaac Walton League
Colleges/Universities
UNC Ins itute of Marine Science
Duke Un versity Department of Geology
Cape Fear Community College
Companies and Individuals
Carteret-Craven EMC
Carteret County News-Times
Morehead City Shipping Co.
Williams and Haywood, Inc.
T.D. Eure Construction Co.
Wilmington Shipping Company
Sailcraft, Inc.
Texasgulf, Inc.
Great Lakes Dredge and Dock Company
Stevens Towing Company
Stroud Engineering
Timber and Land Management
Aviation Fuel Terminals
George Davenport
Grady Davis
John Hooten
T. 0. Talton
12
Companies and Individuals (cont'd)
Don Taylor
R. T. Jones
Luther Smith and Son
Lloyd Wood
Alex Malpass
Galvin Mason
R. W. Chambers
John Fussel
Frank Hatsel
Walter Gentry
Haywood Weeks
William Whaley
Anne McCrary
Vince Bellis
Ray Brandi
Orrin Pilkey
Claude Brown
W. D. Aman
8.00 POINT OF CONTACT
Any comments or questions regarding this EA should be addressed to
Mr. Frank Yelverton, Environmental Resources Section, U.S. Army Corps of
Engineers, Wilmington District, PO Box 1890, Wilmington, North Carolina
28402-1890. Telephone contact is 910-251-4640.
9.00 ENVIRONMENTAL COMMITMENTS
For the first 2 years of maintenance, the shoals enlarged by the sidecast
dredge will be monitored annually or after each dredging event, whichever is
more frequent. Monitoring will include change in elevation and areal extent of
the shoals and establishment of seagrass beds. Monitoring results will be
coordinated with all interested parties. When available, use of the CURRITUCK
is preferred versus use of a sidecast dredge for removal of shoals in the
connecting channel.
13
10.00 REFERENCES
Moser, M. L. and S. W. Ross. 1993. Distribution and Movements of Shortnose
Sturgeon (Acipenser brevirostrum) and Other Anadromous Fishes of the
Lower Cape Fear River, North Carolina. Final Report to the U.S. Army Corps
of Engineers, Wilmington District, May 1993. 112 pp.
National Marine Fisheries Service. 1991. Biological Opinion, Dredging of
Channels in the Southeastern United States from North Carolina Through
Cape Canaveral, Florida. November 25, 1991.
N.C. Division of Marine Fisheries. 1997. Mike Marshall, personal
communication.
Schwartz, F.J. 1995. Florida Manatees, Trichechus manatus (Sirenia
Trichechidae), in North Carolina 1919-1994. Brimleyana No. 22:53-60.
June 1995.
U.S. Army Corps of Engineers, Wilmington District. 1995a. Environmental
Assessment, Maintenance of Drum Inlet, Carteret County, North Carolina.
Environmental Resources Section, January 1995.
U.S. Army Corps of Engineers, Wilmington District. 1995b. Biological
Assessment on findings of may affect on piping plover and seabeach
amaranth by the maintenance of Drum Inlet. Environmental Resources
Section. May 2, 1995.
U.S. Fish and Wildlife Service. 1995. Biological Opinion of the effects on the
Federally-threatened piping plover and seabeach amaranth by the
maintenance of Drum Inlet. Raleigh Field Office. June 30, 1995.
11.00 FINDING
The proposed action should not significantly affect the quality of the
human environment; therefore, an Environmental Impact Statement will probably
not be required. If this opinion is upheld following circulation of this EA, a
Finding of No Significant Impact (FONSI) will be signed and circulated.
14
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Table 3. Shoals Enlarged by Sidecast Dredging at Drum Inlet, NC, Spring 1997
Maximum Elevation (feet)
Above MLW
Average Elevation (feet)
Above MLW
Area (acres)
Above MHW
Area (acres)
Above MLW
Decrease (May-July)
% Decrease
Volume of sand (cubic yards)
Above MLW
Decrease (May-July)
% Decrease
SHOALS ENLARGED ADJACENT TO CONNECTING CHANNEL
May 20, 1997 Survey July 22, 1997 Survey
2.5 1.3
1.10
0.38
5.41
0.68
0.00
3.87
1.54
28%
9,360
4,189
5,171
55%
MLW - mean low water
MHW - mean high water (+ 2 feet MLW)
N420000
N417600
N415000
N4125M
N410000
N407500
FIGURE I.
SEAGRASS BEDS ON 1997 PHOTOGRAPHY
AT DRUM INLET, NC
SCALE: 1" = 2000'IFF 1996 GRASS BEDS
1997 GRASS BEDS
Feet
2000 0 2000 4000
GRID BASED ON NORTH CAROLINA STATE PLANE (NAD83) DIwCOWS m"S
OF 191IGMIM
,LJWNGT0K NORM CAROLWA V
DATE OF PHOTOGRAPHY: MAY 17, 1997
1997 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY AMERICAN GEOGRAPHIC DATA INC.
5710 OLEANDER DRNE. SUITE 108
DATED MAY 17, 1997 WILMINGTON. NC 28403
(910) 392-1498
1996 GRASS BEDS DIGITIZED FROM PHOTOGRAPHY
DATED MAY 23.1996
N420000
N417500
N416000
N412SW
N41OW-
N40750C
E2797500 E2800000 E2802500 E2805000 E2807500 E2810000
R.'
?.
Y
i
SECTION 404(B)(1) (PUBLIC LAW 95-217) EVALUATION
Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina
Evaluation of Section 404(b)(1) Guidelines
40 CFR 230
C7
1. Review of Compliance (230.10(a)-(d))
Review of the NEPA Document indicates:
a. The discharge represents the least
environmentally damaging practicable
alternative and if in a special aquatic
site, the activity associated with the
discharge must have direct access or
proximity to, or be located in the
aquatic ecosystem to fulfill its basic
purpose (if no, see section 2 and NEPA
document);
b. The activity does not: 1) violate
applicable State water quality
standards or effluent standards
prohibited under Section 307 of the
CWA; 2) jeopardize the existence of
federally listed endangered or
threatened species or their habitat;
and 3) violate requirements of any
federally designated marine sanctuary
(if no, see section 2b and check
responses from resource and water
quality certifying agencies);
C. The activity will not cause or
contribute to significant degradation
of waters of the U.S. including adverse
effects on human health, life stages of
organisms dependent on the aquatic
ecosystem, ecosystem diversity,
productivity and stability, and
recreational, aesthetic, and
economic values (if no, see section
2) ;
d. Appropriate and practicable steps have
been taken to minimize potential
adverse impacts of the discharge on
the aquatic ecosystem
(if no, see section 5).
Proceed to Section 2
*, 1, 2/ See page A-6
Preliminary 1/ Final 2/
YESI 1 NOI I* YESIXI N011
YESI 1 NO1 I* YES1X1 N01 I
YESI 1 NOI I* YESIXI N011
YESI 1 NOJ I* YESIXI N011
A-1
Not Signifi- Signifi-
2. Technical Evaluation Factors (Subparts C-F) N/A cant cant*
a. Physical and Chemical Characteristics
of the Aquatic Ecosystem (Subpart C)
(1) Substrate impacts.
(2) Suspended particulates/turbidity
impacts.
(3) Water column impacts.
(4) Alteration of current patterns
and water circulation.
(5) Alteration of normal water
fluctuations/hydroperiod.
(6) Alteration of salinity
gradients.
b. Biological Characteristics of the
Aquatic Ecosystem (Subpart D)
I I X I I
I I I I
I I X I I
I I X I I
I I I I
I I X I I
I I I I
I I X I I
I I I I
I I X I I
(1) Effect on threatened/endangered I I I I
species and their habitat. I I X I I
(2) Effect on the aquatic food web. I I X I I
(3) Effect on other wildlife (mammals, I ( I
birds, reptiles, and amphibians). I I X I
C. Special Aquatic Sites (Subpart E)
(1) Sanctuaries and refuges.
(2) Wetlands.
(3) Mud flats.
(4) Vegetated shallows.
(5) Coral reefs.
(6) Riffle and pool complexes.
d. Human Use Characteristics (Subpart F)
I X I I I
I X l I I
I X I I I
I X I I I
I X I I I
I X I I I
(1) Effects on municipal and private I I I I
water supplies. ( X I I I
(2) Recreational and commercial I I I I
fisheries impacts. I I X I I
(3) Effects on water-related recreation.) I X 1 1
(4) Aesthetic impacts. I I X I I
(5) Effects on parks, national and I I I I
historical monuments, national I I I I
seashores, wilderness areas, I I I I
research sites, and similar I I I I
preserves. I X I I I
Remarks: Where a mark is placed under
the significant category, preparer add
explanation below.
Proceed to Section 3
*See page A-6
W
A-2
3. Evaluation of Dredged or Fill Material (Subpart G) 3/
a. The following information has been
considered in evaluating the biological
availability of possible contaminants in
dredged or fill material. (Mark only
those appropriate.)
(1) Physical characteristics . . . . . . . . . . . . . . . . . .IXI
(2) Hydrography in relation to
known or anticipated _
sources.of contaminants . . . . . . . . . . . . . . . . . . . 1X1
(3) Results from previous
testing of the material
or similar material in _
the vicinity of the project . . . . . . . . . . . . . . . . . I X 1
(4) Known, significant sources of
persistent pesticides from _
land runoff or percolation . . . . . . . . . . . . . . . . . .I 1
(5) Spill records for petroleum
products or designated
(Section 311 of CWA) _
hazardous substances . . . . . . . . . . . . . . . . . . . . . I I
(6) Other public records of
significant introduction of
contaminants from industries,
municipalities, or other _
sources . . . . . . . . . . . . . . . . . . . . . . . . . . .I I
(7) Known existence of substantial
material deposits of
substances which could be
released in harmful quantities
to the aquatic environment by _
man-induced discharge activities . . . . . . . . . . . . . I I
(8) Other sources (specify) . . . . . . . . . . . . . . . .. . . 1 I
List appropriate references.
EA "Maintenance of Drum Inlet, Carteret County,
North Carolina," dated January 1995
EA "Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina," dated August 1997
b. An evaluation of the appropriate information in 3a
above indicates that there is reason to believe the
proposed dredge or fill material is not a carrier of
contaminants, or that levels of contaminants are sub-
stantively similar at extraction and disposal sites and
not likely to result in degradation of the disposal site.
The material meets the testing exclusion criteria. YES 1X1 NO 1_1*
Proceed to Section 4
*, 3/, see page A-6
A-3
4. Disposal Site Determinations (230.11(f)).
a. The following factors as appropriate,
have been considered in evaluating the
disposal site.
(1) Depth of water at disposal site . . . . . . . . . . . . IXI
(2) Current velocity, direction, and
variability at disposal site . . . . . . . . _
. . . . . IXI
(3) Degree of turbulence . . . . . . . . . . . . . . . . . I X I
(4) Water column stratification . . . . . . . . . . . . . . IXI
(5) Discharge vessel speed and
direction . . . . . . . . . . . . .. . . . . _
. . . . . I X I
(6) Rate of discharge . . . . . . . . . . . . . . . . . . I X I
(7) Dredged material characteristics
(constituents, amount and type
of material, settling velocities). . . . . . _
. . . . . .IXI
(8) Number of discharges per unit of _
time . . . . . . . . . . . . . . . . . . . . . . . . . IXI
(9) Other factors affecting rates and
patterns of mixing (specify)
List appropriate references.
EA "Maintenance of Drum Inlet, Carteret County,
North Carolina," dated January 1995
EA "Use of Sidecast Dredge or Hopper Dredge CURRITUCK with
Overflow as Additional Maintenance Dredging Methods for
Drum Inlet, North Carolina," dated August 1997
b. An evaluation of the appropriate factors in
4a above indicates that the disposal site
and/or size of mixing zone are acceptable . . . .YES 1XI NO 1-1*
5. Actions to Minimize Adverse Effects (Subpart H).
All appropriate and practicable steps have been taken,
through application of recommendations of 230.70-230.77,
to ensure minimal adverse effects of the proposed
discharge. List actions taken. YES IXI NO 11*
See sections 4.01 through 4.03 and 9.00 of the 1997 EA.
Return to section 1 for final stage of compliance review. See also
note 3/, page A-6.
*See page A-6
4
S
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a
6. Factual Determinations (230.11).
A review of appropriate information as identified in
items 2-5 above indicates that there is minimal
potential for short- or long-term environmental
effects of the proposed discharge as related to:
a. Physical substrate at the disposal site
(review sections 2a, 3, 4, and 5). YES IXI NO 11*
b. Water circulation, fluctuation, and salinity
(review sections 2a, 3, 4, and 5). YES IXI NO 11*
c. Suspended particulates/turbidity
(review sections 2a, 3, 4, and 5). YES 1XI NO 1-1*
d. Contaminant availability
(review sections 2a, 3, and 4). YES 1XI NO 1-1*
e. Aquatic ecosystem structure and function YES IXI NO 1_1*
(review sections 2b and c, 3, and 5).
f. Disposal site
(review sections 2, 4, and 5). YES 1XI NO 1-1*
g. Cumulative impact on the aquatic
ecosystem. YES IXI NO 11*
h. Secondary impacts on the aquatic
ecosystem. YES 1XI NO 1-1*
7. Findings.
a. The proposed disposal site for discharge of
dredged or fill material complies with the
Section 404(b)(1) guidelines . . . . . . . . . _
. . . . . . . .IXI
b. The proposed disposal site for discharge of
dredged or fill material complies with the
Section 404(b)(1) guidelines with the _
inclusion of the following conditions: ( I
*See page A-6
A-5
C. The proposed disposal site for discharge of
dredged or fill material does not comply with
the Section 404(b)(1) guidelines for the
following reasons(s):
(1) There is a less damaging practicable alternative. . . . . I I
(2) The proposed discharge will result in significant _
degradation of the aquatic ecosystem . . . . . . . . . . I I
(3) The proposed discharge does not include all
practicable and appropriate measures to minimize _
potential harm to the aquatic ecosystem . . . . . . . . . I I
8.
C.E. Shut/rd, Jr., P.E.
Acting Chief, Engineering
and Planning Division
Date:
*A negative, significant, or unknown response indicates that the permit application may
not be in compliance with the Section 404(b)(1) Guidelines.
1/ Negative responses to three or more of the compliance criteria at this stage
indicate that the proposed projects may not be evaluated using this "short form
procedure." Care should be used in assessing pertinent portions of the technical
information of items 2 a-d, before completing the final review of compliance.
2/ Negative response to one of the compliance criteria at this stage indicates that the
proposed project does not comply with the guidelines. If the economics of navigation
and anchorage of Section 404(b)(2) are to be evaluated in the decision-making process,
the "short form evaluation process is inappropriate."
3/ If the dredged or fill material cannot be excluded from individual testing, the
"short-form" evaluation process is inappropriate.
J
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