19941101 Ver 1_COMPLETE FILE_19941207

State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Environmental Management
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
ID FE P1
December 29, 1994
Beaufort County
DEM Project # 941101
APPROVAL of 401 Water Quality Certification
Mr. Ed Burchins, Mayor
City of Washington
102 East Second St.
Washington, N.C. 27889
FILE COPY
Dear Mr. Burchins:
You have our approval to place fill material in 0.43 acres of wetlands or waters for the purpose
of constructing a sanitary sewer discharge pipe at Kennedy Creek into Tar River, as you described in
your application dated 2 December 1994. After reviewing your application, we have decided that this
fill is covered by General Water Quality Certification Number 2664. This certification allows you to
use Nationwide Permit Number 12 when it is issued by the Corps of Engineers.
This approval is only valid for the purpose and design that you described in your application. If
you change your project, you must notify us and you may be required to send us a new application.
For this approval to be valid, you must follow the conditions listed in the attached certification. In
addition, you should get any other federal, state or local permits before you go ahead with your
project.
If you do not accept any of the conditions of this certification, you may ask for an adjudicatory
hearing. You must act within 30 days of the date that you receive this letter. To ask for a hearing,
send a written petition which conforms to Chapter 150B of the North Carolina General Statutes to the
Office of Administrative Hearings, P.O. Box 27447, Raleigh, N.C. 27611-7447. This certification and
its conditions are final and binding unless you ask for a hearing.
This letter completes the review of the Division of Environmental Management under Section 401
of the Clean Water Act. If you have any questions, please telephone John Domey at 919-733-1786.
Si rely,
P ston Howard, Jr. P.E.
Attachment
cc: Wilmington District Corps of Engineers
Corps of Engineers Washington Field Office
Washington DEM Regional Office
Mr. John Dorney
Central Files
John Parker; DCM
941101.Itr
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
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DIVISION OF COASTAL MANAGEMENT + i r
FIELD INVESTIGATION REPORT i!
1. APPLICANT'S NAME: City of Washington
2. LOCATION OF PROJECT SITE: Beaufort County, Plymouth Street, Kennedy Creek, Tar River
Photo Index - 1989: 264-15, H-11, G-11, F-11, E-12, D-12, etc.
1984: 73-584, J-8, I-8, H-9, G-9, F-9, etc.
State Plane Coordinates - X: 2,572,000 Y: 660,500 City of Washington UL
3. INVESTIGATION TYPE: CAMA
4. INVESTIGATIVE PROCEDURE: Dates of Site Visit - 31 October 1994
Was Applicant Present - Yes
5. PROCESSING PROCEDURE: Application Received - 8 November 1994
Office - Washington
6. SITE DESCRIPTION:
(A) Local Land Use Plan - City of Washington
Land Classification From LUP - Conservation
(B) AEC(s) Involved: Public Trust Area
(C) Water Dependent: Yes
(D) Intended Use: Discharge of sanitary wastewater
(E) Wastewater Treatment: Existing - Discharge to Kennedy Creek
Planned - Discharge to Tar River
(F) Type of Structures: Existing - Discharge pipe
Planned - 20" HDPE discharge line with diffuser
(G) Estimated Annual Rate of Erosion: N/A
Source - N/A
7. HABITAT DESCRIPTION: [AREA]
DRFDnFn RTT T rn f% VT TT-n
(A) Vegetated Wetlands
±9,150 sq. ft. ±6,000 sq. ft.
Temporary Fill
(B) Non-Vegetated Wetlands
(C) Other
Open water 3,800 sq. ft.
(D) Total Area Disturbed: ± 18,950 sq. ft. or 0.43 acres
(E) Primary Nursery Area: No
(F) Water Classification: C-NSW Open: No
8. PROJECT SUMMARY: The applicant is proposing to construct a 2,520' long sanitary sewer
discharge pipe with a 30' diffuser at the waterward end across Kennedy Creek into the Tar River.

CITY OF WASHINGTON
Beaufort County
Environmental setting
This project that is being proposed by the applicant is located on Plymouth Street within
the City of Washington in Beaufort County. Located at the site is the existing sanitary
wastewater treatment plant which serves the city. The facility presently discharges its effluent
into adjacent Kennedy Creek, however due to the city's desire to increase the plant capacity, a
decision has been made to remove the effluent discharge from Kennedy Creek to the Tar River
of which Kennedy Creek is a tributary.
Kennedy Creek, which lies directly adjacent to and to the south the treatment facility, has
a width of ±450' at this location. Adjacent to the creek, landward of the NWL, is a small
wetland area which is dominated by Carex. sue.. The creek is relatively shallow an has a
maximum depth of -4' at normal water near its center. The creek is separated from the Tar
River by a peninsula which has a width at this location of ±600'. At this site the entire
peninsula appears to be a wetland area being vegetated by various vegetation such as Carex M.
golden rod, cypress, and myrtles. At the site the peninsula has a lack of overstory thus not
resembling a wooded swamp system. To the south of the peninsula is the Tar River which has
a width of ±1,819' at this location. Immediately south of the peninsula the river bottom
gradually declines to a depth of approximately -7' at normal water; it then becomes shallow in
the vicinity of a natural sandbar where a depth of slightly greater than -2' at normal water. The
river there begins to deepen again an reaches a maximum depth of -12.5' at normal water in the
river channel. This location is approximately 2,550' south of the normal water line on the north
side of Kennedy Creek at the wastewater treatment site.
Project proposal
The applicant is proposing to eliminate the existing wastewater discharge into Kennedy
Creek an to place it into the Tar River. This will be accomplished by the placement of 2,550'
of 20" HDPE in the river. The final 30' will be a diffuser which will dispense the effluent. As
the pipe leaves the north shore of Kennedy Creek it will be jetted a minimum of -2', including
the concrete collars, below the existing creek bottom, the entire width of the creek. At this
point the pipe will be placed across the peninsula where it will be buried a minimum of 1' below
existing grade. The proposal is to excavate a 15' wide top width trench with a backhoe to a
depth of -3'. Spoil from the excavation of the trench will be placed temporarily beside the
trench within a 10' wide maximum area. Once the pipe is in place the spoil will be replaced
within the trench and excess spoil will be removed to a suitable highground site. Once across
the peninsula the pipe will again be jetted below the bottom of the Tar River a minimum of -2'.
The final 30' of the pipe will lay on the channel bottom and will be designed as a diffuser with
effluent holes 2' apart and a plugged end.
CITY OF WASHINGTON
Beaufort County
Page 2
Environmental imyact
The project as proposed will have the following environmental it r?acts:
(1) ±9,150 sq. ft. of non-coastal wetlands (marsh) will be excavated.
(2) ±6,000 sq. ft. of non-coastal wetlands (marsh) will be temporarily filled by
material from trench excavation on the peninsula.
(3) ±3,800 sq. ft. of sediments within Kennedy Creek and the Tar River will be
disturbed during the jetting of the pipe.
(4) Short term turbidity will exist during project construction from jetting of the pipe.
David L. Gossett - Washington Regional Office - 21 November 1994
Please type or print. Carefully describe all anticipated
development activities, including construction, excava-
tion, filling, paving, land clearing, and stormwater con-
trol. If the requested information is not relevant to your
project, write N/A (not applicable). Items 1-4 and 8-9
must be completed for all projects.
1 APPLICANT
a. Name City of Washington
Address 102 East Second Street
City Washington
State North Carolina
Zip 27889 Day phone [phone]
x Landowner or Authorized agent
b. -Project name (ifany) City of Washing-ton,
Wastewater Facilities Improvements
c. If the applicant is not the landowner, also give the
owner's name and address.
See attachment lc.
2 LOCATION OF PROPOSED
PROJECT
a. Street address or secondary road number
Plymouth Street
b. City, town, community, or landmark
Washington, North Carolina
c. County
Beaufort
d. Is proposed work within city limits or planning
jurisdiction? Yes
e. Name of body of water nearest project
Kennedy Creek, Tar River
3 DESCRIPTION AND PLANNED USE
OF PROPOSED PROJECT
If you plan to build a marina, also complete and
attach Form DCM-MP-2.
b. Is the proposed activity maintenance of an
existing project, new work, or both?
New work
c. Will the project be for community, private, or
commercial use?
Community (Public Works)
d. Describe the planned use of the project.
Transmission/diffused discharge
of treated municipal wastewater
4 LAND AND WATER
CHARACTERISTICS
0 25 0
a. Size of entire tract approximately n 3-acre
b. Size of individual lot(s) N/A
c. Elevation of tract above mean sea level or
National Geodetic Vertical Datum '
Ranges from -12.0 feet below MSL to
+ 1.0 above MSL.
d. Soil type(s) and texture(s) of tract
See attachment 4d.
e. Vegetation on tract See attachment 4e.
f. Man-made features now on tract Existing 36 i n c h
DIP outfall to Kennedy Cree . o remain.
g. What is the CAMA Land Use Plan Classification of
the site? (Consult the local land use plan.)
X Conservation Transitional
-Developed Community
Rural Other
h. How is the tract zoned by local government?
WWTP: I-2; Peninsula between Kennedy Creek
ano iar Kiver: i-1
i. How are adjacent waters classified?
Tar River: Class C - NSW
a. Describe all development activities you propose (for j. Hasa professional archaeological survey been
exl-:nple, building a home, motel, marina, bulkhead, carried out for the tract? Yes If so, by whom?
or pier). New 20-inch HDPE submerged See attachment 4j. -
outfall with pipe diffuser in Tar River
3/91
5 UPLAND DEVELOPMENT
Complete this section if the project includes any land
development.
a. Type and number of buildings, facilities, or
structures proposed N/A
b. Number of lots or parcels N/A
c. Density (Give the number of residential units and the
units per acre.) N/A
m. Water supply source N/A
n. If the project is oceanfront development, describe
the steps that will be taken to maintain established
public beach accessways or provide new access.
No oceanfront development.
d. Size of area to be graded or disturbed
See attachment 5d.
e. If the proposed project will disturb more than one
acre of land, the Division of Land Resources must
receive an erosion and sedimentation control plan at
least 30 daysbbefore land disturbing activity begins.
If applicable, has a sedimentation and erosion
control plan been submitted to the Division of Land
Resources? N/A
f. Give the percentage of the tract within 75 feet of
mean high water to be covered by impermeable
surfan/,?ch as pavement; btiiIdings, rooftops.
o. If the project is on the oceanfront, what will be the
elevation above mean sea level of the first habitable
Hoof? No oceanfront development.__
6 EXCAVATION AND FILL
. INFORMATION
a. Describe below the purpose of proposed excavation
or fill activities (excluding bulkheads, which are
covered in Section 7).
Length Width Depth
g. List the materials, such as marl, paver stone, asphalt, Pipe- trench
or concrete, to be used for paved surfaces. (MI.W) or (NWL)
N/A ,
Boat basin
h. If applicable, has a stormwater management plan Other (break-
been submitted to the Division of Environmental water, pier,
Management? No impervious area will boat ramp,
be constructed. rockjetty)
i. Describe proposed sewage disposal and/or waste
water treatment facilities. Fill placed in
3.2 MGD activated sludge treatment wetland or below
plant with tertiary filters. - MHW
j. Have these facilities received state or local approval? Upland fill
Yes areas
_*, 12" min cover across peninsula
b. Amount of material to be excavated from below
k. Describe existing treatment facilities.
Bar screens, grit removal; activated sludge
treatment, clarification, tertiary filters,c.
chlorination, dechlorination, an
reaeration. d,
1. Describe location and type of discharges to waters of
the state (for example, surface runoff, sanitary
wastewater, industrial/commercial effluent, "wash
down"). Treated sanitary wastewater e
effluent.
water level in cubic yards 2300 cv
Typeofmaterial River bottom
See attachment
Does the area to be excavated include marshland,
swamps, or other wetlands?
Yes
High ground excavation, in cubic yards
N/A
2 3/91
f. Dimensions of spoil disposal area
Approximately 80 cy
g. Location of spoil disposal area To be determined
by contractor in accordance with all
applicable regulations.
h. Do you claim title to the disposal area? N/A
If not, attach a letter granting permission from the
owner.
i. Will a disposal area be available for future
maintenance? N/A
If so, where? N/A
j. Does the disposal area include any marshland,
swamps, or water areas?
k. Will the fill material be placed below mean high
water? N/A
1. Amount of fill in cubic yards No fill material.
m. Type of fill material N/A
n. Source of fill , material N/A
o. Willfillmat ri l be vlac d o mfrlsNo prier to
wetlands? e s' p. Dimensinns of the wetland to be filled
Less than 10 ft. wide along tranch
q. How will excavated or fill material be kept on site
and erosion rnntrnllpri?
Excess trench material to be removed
to high group an area reseeded
with fescue
r. What type of construction equipment will be used
(for example, dragline, backhoe, or hydraulic
dredge)? Barge crane to move pipe and
concrete ballast, pressure-jetting
equipment to bury pipe.
s. Will wetlands be crossed in transporting equipment
to project site? Y e s If yes, explain steps that will
be taken to lessen envirnnmentnl imnnr.tz.
A trackhoe will travel along matting
installed around the trench. Matting
will provide firm base for trackhoe
and protect marsh from excess rutting.
7 SHORELINE STABILIZATION
a. Length of bulkhead or riprap N/A
b. Average distance waterward of mean high water or
normal waterlevel N/A
c. Shoreline erosion during preceding 12 months, in
feet Less than 2 feet/year (per telephone
conversation with Div. of Coastal Management)
d. Type of bulkhead material N/A
e. Amount of fill, in cubic yards, to be placed below
mean high water None
f. Type of fill material None
8 ADDITIONAL INFORMATION
In addition to the completed application form, the follow-
ing items must be submitted:
A copy of the deed (with state application only) or other
instrument under which the applicant claims title to the
affected property. If the applicant is not claiming to be
the owner of said property, then forward a copy of the
deed or other instrument under which the owner claims
title, plus written permission from the owner to carry out
the project. See attachment lc.
An accurate work plat (including plan view and cross
sectional drawings) drawn to scale in black ink on an 8
1/2 x 11 white paper. (Refer to Coastal Resources
Commission Rule 7J.0203 for a detailed description.)
Please note that original drawings are preferred and
only high quality copies will be accepted. Blue-line
prints or other larger plats are acceptable only if 18 high
quality copies are provided by applicant. (Contact the
U.S. Army Corps of Engineers regarding that agency's
use of larger drawings.) A site or location map is a part
of plat requirements and it must be sufficiently detailed
to guide agency personnel unfamiliar with the area to the
site. Include county road (SR) numbers, landmarks, and
the like. See attachment package.
A stormwater management plan, if applicable, that
may have been developed in consultation with the
Division of Environmental Management. N/A
A list of the names and complete addresses of the
adjacent waterfront (riparian) landowners. These
individuals have 30 days in which to submit comments
on the proposed project to the Division of Coastal
Management and should be advised by the applicant of
that opportunity.
3/91
Name ?National Spinning Company
Address P.O. Box 191
Washington, North Carolina 27889
Name T.on Taylor
Address 157 Tar Heel Drive
Washington, North Carolina 27889
Name
Address
A list of previous state or federal permits issued for
work on the project tract.' Include permit numbers,
permittee, and issuing dates.
NPDES: NC0020648 (Existing discharge)
Land Application Permit: WQ0001026
A check for $250 made payable to the Department of
Environment, Health, and Natural Resources to cover
the costs of processing the,.application. Attached.
A signed AEC hazard notice for projects in oceanfront
and inlet areas. N/A
A statement on the use of public funds. If the project
involves the expenditure of public funds, attach a state-
ment documenting compliance with the North Carolina
Environmental Policy Act (N.C.G.S. 113A-1 to 10).
9 CERTIFICATION AND PERMISSION
TO ENTER ON LAND
Any permit issued in response to this application will
allow only the development described in the application.
The project will be subject to conditions and restrictions
contained in the permit.
I certify that to the best of my knowledge, the proposed
activity complies with the State of North Carolina's ap-
proved Coastal Management Program and will be con-
ducted in a manner consistent with suchprogram.
I further certify that I am authorized to grant, and do in
fact, grant permission to representatives of state and
federal review agencies to enter on the aforementioned
lands in connection with evaluating information related
to this permit application and follow-up monitoring of
project.
This is the y o 19
X
Lando eror A thorized agent
This project complies with the
North Carolina Environmental Policy Act (N.C.G.S. 113A-1 to 10).
Edward Burchins, Manager Date
City of Washington, North Carolina
4 3/91
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City of Washington B&V Project 19975.350
Tar River Discharge - CAMA Permit August 9, 1994
ATTACHMENT lc.
This project includes the construction of 2,550 feet of a 20-inch high-
density polyethylene (HDPE) pipe outfall to the Tar River from the
Washington Wastewater Treatment Plant. The pipe will be installed
across Kennedy Creek, across a small peninsula between Kennedy Creek and
the Tar River, and into the Tar River.
The City of Washington is in the process of procuring a 30-foot wide
permanent easement across the peninsula between the creek and river.
The easement deed, between the City (Grantee) and Mr. Julian Rhem
(Grantor), is to be attached as a part of this permit application.
The Landowner address is listed below:
City of Washington
102 East Second Street
Washington, North Carolina 27889
City of Washington, NC B&V Project 19975.350
Tar River Discharge - CAMA Permit August 9, 1994
ATTACHMENT 4d.
Soil type(s) and texture(s). Marine sediments dominate the area.
Upland soils at the wastewater treatment plant typically consist of
interbedded zones of sand, silt, and clay with irregular deposits of
shells. Kennedy Creek has a soft, silty bottom, and the Tar River has a
firm, sandy bottom.
Additional information is provided in an excerpt (copy attached)
from a paper by Stanley R. Riggs, et al., entitled "Heavy Metal
Pollutants in Organic-Rich Muds of the Pamlico River Estuarine System:
Their Concentration, Distribution, and Effects Upon Benthic Environments
and Water Quality" (East Carolina University, Greenville, North
Carolina, December 20, 1989). Also, elutriate testing currently being
performed at the site will provide more data.
ATTACHMENT 4e.
Vegetation on tract. Vegetation on the peninsula between Kennedy Creek
and the Tar River is characterized in a letter to Mr. Michael Shafer,
Black & Veatch, dated April 1, 1994, from Vincent Bellis, E.C.U.
Professor of Biology. A copy of this letter is attached to the
application.
ATTACHMENT 4j.
Archaeological survey. A review of potential architectural, historic,
or archaeological properties was conducted at the wastewater treatment
plant site. In a letter to Mr. Larry Pearce, Black & Veatch, dated
November 12, 1993, it was stated that no significant properties would be
affected by the project. A copy of this letter from Mr. David Brook, is
attached to the application.
Also, a request was submitted on August 1, 1994, for an
archaeological review of the small peninsula between Kennedy Creek and
the Tar River. A letter and maps were sent to Ms. Renee Gledhill-Earley
of the North Carolina Department of Cultural Resources for review of the
subject property. It is not anticipated that any properties of historic
significance will be identified on the peninsula.
r
ATTACHMENT 4d.
RESULTS
Estuarine Mor2holog and Sediment 'composition
Table 14 summarizes the sediment particle size and composition for 344
subaamplon analyzed throughout the Pamlico estuarine system. Note the
extremely high, but variable concentrations of both organic matter and clay
components. The distribution, concentration, and composition of these two
components appear to by the most important factors in determining a) which
metals are concentrated in the sediment, b) specific levels of metal
concentration, c) chemical state of the metals, and d) chemical availability
to the biological syetem. However, these factors are poorly understood at
present and are a major part of ongoing research efforts.
TABLE 14. Summary of sediment
suboamples of the Pamlico River composition
estuarine and particle
system. size for
ARLA % SAND % SILT % CLAY % ORGANIC % INORGANIC
Tar River Mouth 45 52.6 21.9 25.5 13.9 86.1
Trantexs Creek 6 79.9 9.6 10.4 7.3 92.7
Kennedy Creek 32 46.6 28.0 25.4 25.0 75.0
Pamlico Trunk 113 18.6 30.9 50.9 8.2 91.8
Chocowinity Day 10- 81.0 10.0 9.0 17.7 82.3
Whichards Creek 5 39.5 32.2 29.3 9.8 90.8
Broad Creek 14 34.4 25.2 40.3 14.8 85.2
Alounts Creek .2 47.2 26.0 26.8 6.3 93.7
Bath Creek 8 17.1 45.1 37.5 10.0 90.0
Mixon Creek 2 38.6 25.2 36.2 28.9 71.1
Durham Creek 7 22.2 30.5 47.3 10.7 89.3
South Creek 30 14.6 28.0 57.4 11.1 88.9
Inner Pungo River 44 32.2 29.4 38.4 13.5 86.5
Outer Pungo River 10 11.1 34.7 54.2 7.6 92.4
Pantego Creek 13 42.9 22.1 35.0 8.2 91.8
Pungo Creek 4 16.7 29.b 53.7 11.0 89.0
Organic-rich mud sediments (tip to 57% total organic matter) generally
occupy the entire bottom environment within tributary estuaries and about 75%
to 80% of the bottom environments within the fluvial and transition zones of
the lowor Tar River and trunk of the Pamlico River estuary (Fig. 10) (8el.lis
et al., 1975; Hartness, 1977; Hardaway, 1980;'Riggs, 1985). Concentration of
organic material in individual sampkes ranges up to 57% of the total
sediment. Sediments that generally contain greater than 25% organic matter
are pvats that represent either in situ growth in swamp forests and grass
marshes or secondary accumulations of coarse organic detritus eroded out of
swamp forests and grass marshes. organic-rich sediments generally having
less than 25% organic matter are fine-grained muds with minor sand contents.
Swamp forest post sediments are dominant in the fluvial and transition
zones of the Tar River and headwaters of associated lateral tributary
estuaries. Within the fluvial portion, organic material occurs as swamp

Eoront peaty on the channel flanks and as coarse organic detritus mixed with
coarse nand within the channel proper (Fig. 11). Within the narrow
transition zones (Fig. 10) inr-n a flooded estuary, the channel remains
dominated by coarse sands and coarse organic matter; however, the swamp
forest has been drowned and mud, containing high concentrations of very
fine-grained organic detritus, begins to accumulate on top of swamp forest
peats an the channel flanks. Swamp forest peats decrease in abundance into
the main portions of the tributary and trunk estuaries; marsh peaks occur
around some of the perimeter areas while swamp forest peats occur preserved
beneath increasingly thicker accumulations of the organic-rich muds.
Immediately seaward of the transition zone, there is a sediment inversion
(Riggs, 1985); the estuarine platforms are underlain by tight Pleistocene
sediment units and covered by a thin and highly variable layer of well-sorted
Band (Vig. 12) (Hartness, 1911; Hardaway, 1980). Within this main portion of
the Pamlico River estuary, organic-rich mud sedimentation occurs within the
broad, deeper portions of the estuaries. These mud-filled, depositional
basins are incised into the shallow platforms that are underlain by older,
more indurated Pleistocene sediment units.
The organic-r=ich mud increas9s in width, depth, and thickness in
downstream directions within both the trunk and lateral tributary channels
(Hartnese, 1975). The content of organic matter is generally less than 25% in
the organic-rich muds and is generally highest in the lateral tributaries and
decreases into the trunk estuary and seaward down the trunk estuary (Fig.
13) Benthic environments associated with the organic-rich mud contain an
oxidized zone of loose floc of variable thickness. The presence or absence
and the degree of development of the loose floc at the sediment/water
interface is a direct function of the productivity and storm energy levels,
both of which vary greatly at scales ranging from daily to seasonal cycles.
The surface sediments become reduced and increasingly compacted with depth.
In addition to a large population of micro-organisms, this sediment/water
interface zone contains a large community of filter-feeding macrobenthos,
particularly polychaetes (Tenore, 1977), that appear to be important in
concentrating, pelletizing, and depositing the mud sediment.
Dates of Sedimentation
Carbon 14 age-dates were obtained an four organic-rich samples in a 4
mete; core (Fig. 14) from the inner portion of Blounts Bay (Fig. 10). The
basal sample is from a swamp forest peat deposited in a lower pluvial
environment, which was at or slightly•alaove sea level at the time of
formation. The upper three samples are organic-rich muds that represent
deposition in an aquatic, inner estuarine environment seaward of the
transition zone (Fig. 10). 'She resulting curve (Fig. 14) reflects the
systematic rise in sea level, flooding up the lateral tributary stream to
form a lateral estuary, and deposition of the organic-rich mud sediments.
General rates of deposition of the organic-rich mud can be calculated
from Figure 14. The mean rate of deposition for the four numbers is 0.61
mm/yr (range from 0.45 mm/yr to 0.70 mm/yr). This suggests that
sedimentation is very slow and that the anthropogenic effects of metal
pollutants should not extend very deep within the sediments. Actual depth of
impact within any specific portion of the estuarine system would be
46

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FIGURE 10. Dasignation of environmental, components for the pamlico River estuarIne
system
45