United States
                         Environmental Protection
                         Agency
                            Office Of Water
                            (WH-553)
EPA841-F-93-010
September 1993
Number 10
oEPA        TMDL   CASE   STUDY
                         Tar-Pamlico  Basin,   North
                         Carolina
     Key Feature:
     Project Name:

     Location:
     Scope/Size:
     Land Type:
     Type of Activity:
     Pollutant:
     TMDL Development:
     Data Sources:
     Data Mechanisms:
    Monitoring Plan:
    Control Measures:
 A trading program between
 municipal dischargers and agriculture
 as an innovative, cost-effective tool
 to meet nutrient reduction goals

 Tar-Pamlico Nutrient Trading
 Program
 USEPA Region IV/North Carolina
 Watershed area 11,650 km2
 Piedmont and Coastal Plain
 Agriculture, urban
 Nitrogen, phosphorus
 No
 State
 Hydrodynamic estuarine model,
 Generalized Watershed Loading
 Functions (GWLF)
 Yes
WWTP operational  improvements,
agricultural BMPs
                                                                                  Tcr-Pamlico Basin
                                                        FIGURE 1.  The Tar-Pamlico basin in North Carolina
    Summary: In recent years, low dissolved oxygen levels, sporadic fish kills, loss of submerged vegetation and other
    water quality problems have plagued North Carolina's Tar-Pamlico basin.  Studies have linked many of these problems to
    increased nitrogen and phosphorus loading to the system.  In 1989, the North Carolina Environmental Management
    Commission (EMC) designated the Tar-Pamlico basin as a Nutrient Sensitive Water. The classification, based on years of
    detailed nutrient loading studies, required the development and implementation of a strategy to manage both point and
    nonpomt nutrient sources to meet water quality goals.

    The North Carolina Division of Environmental Management (NCDEM) responded by developing stricter nitrogen and
    phosphorus effluent standards for dischargers in the basin.  However, dischargers were concerned about the high capital
    costs that might be required to achieve the nutrient reduction goals.  Consequently, a coalition of dischargers  working in
    cooperation with the Environmental Defense Fund, the Pamlico-Tar River Foundation/and NCDEM, proposed a nutrient
    trading framework through which dischargers can pay for the development and implementation of agricultural best
    management practices (BMPs) to achieve all or part of the total nutrient reduction goals.  The EMC approved the program
    in December 1989, and the implementation phase (Phase 1) is  currently under way. As a condition of EMC's approval
    the d.scharger coalition agreed to fund the development of an estuarine model. The model will be used as a tool to   '
    evaluate specific nutrient reduction strategies for the basin.  This information will then be used to revise effluent nutrient
    standards for Phase 2 of the project.  The nutrient trading program is proving to be a popular solution, largely because it
    achieves the state's nutrient reduction goals and addresses nonpoint loadings while also Inducing the economic burden to
    municipal dischargers.
     Contact:   David Harding, North Carolina Department of Environment, Health, and Natural Resources, Division of
               Environmental Management, PO Box 29535, Raleigh, NC 27626-0535, phone (919) 733-5083
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BACKGROUND

Tlie Resource

North Carolina's Tar-Pamlico basin encompasses 11,650
km3 and portions of 17 counties.  Its waters are a highly
valued natural resource that supports commercial and
recreational fisheries,  recreational boating, swimming,
and many other beneficial uses.  The basin also serves as
the primary source of drinking water for eight cities and
towns in central and eastern North Carolina, including
Rocky Mount and Greenville (NCDEM, 1987).

The Tar  River constitutes the upper portion of the basin,
flowing for roughly 140 miles through the North
Carolina piedmont and across the coastal plain (Figure
2). The Tar gradually widens to form the Pamlico River
just east of Washington, North Carolina.  The Pamlico
River becomes the Pamlico Estuary and flows
approximately 35 miles before entering Pamlico Sound
on the North Carolina coast.  The Sound is protected by
an extensive barrier island system with only a few small
inkts connecting to the Atlantic  Ocean (NCDEM, 1989).

Agriculture and forest are the dominant land uses in the
Tar-Pamlico basin. While forest in the upper half of the
basin is  largely undisturbed, a large portion in the lower
coastal plain is managed for logging.  Thirty-seven
percent of the basin is devoted to agriculture, which is
predominantly row crop cultivation and intensive
livestock operations.  Five of the state's 10  leading hog-
producing counties, as well as the leading chicken-
producing county, are in the basin (Harding, 1990).  As
of 1989, there were approximately 875 hog, chicken,
dairy, and turkey operations.  Many of these have
 expanded beyond their original capacities or are using
 outdated waste management facilities. Table 1
 summarizes population data for hogs, cows, and
 chickens in the Tar-Pamlico basin.

 Increasing fertilizer use, expanding livestock operations,
 and a growing human population have been affecting the
 waters of the Tar-Pamlico basin for more than three
 decades,  In recent years, the effects have included
 diseased fish, sporadic fish kills, increased  sediment and
 nutrient loads, phytoplankton blooms, and low dissolved
 oxygen (DO) levels.  High nutrient loads have been
 associated with dinoflagellate blooms in the estuary.
 These blooms produce large amounts of organic carbon,
 which can lead to oxygen depletion in bottom waters; in
 fact, DO concentrations as low as 0.5 mg/L have been
 recorded and associated with fish kills.  The state's DO
 standard for most of the basin is 5 mg/L.  In 1986, 10
 percent of all chlorophyll-a samples taken  in the Pamlico
 Estuary exceeded the state standard of 40 /xg/L (Steel,
 1991). Losses of submerged aquatic vegetation have
 also impaired the economically valuable commercial
 fisheries  in the Pamlico River Estuary (NCDEM, 1987).

 Programmatic Issues

 Declining water  quality has sparked substantial concern
 and activity on the part of the state government and
 environmental organizations such  as the Environmental
 Defense Fund and the Pamlico-Tar River Foundation.
 Several large research projects, including the Albemarle-
 Pamlico Estuarine Study, have studied  the effects of
 nutrients, sediment, and toxic loads on waters in the
 basin. North Carolina's 1992 305(b) report states that
. 59 percent of the stream miles in the Tar-Pamlico basin
 are supporting their designated uses, 25 percent are
 partially supporting, and 7 percent are  not supporting.
 The report identifies agricultural runoff as the major
 source of impairment.
                                                               Blounfi Cr.   South Cr.
                                                                      Durham Cr.
                                                                                            I ltl»nd [--i
                                     FIGURE 2.  Schematic of the Tar-Pamlico Basin

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 TABLE 1.   1990 Livestock Data for the Tar-Pamlico
 Basin (NCDA, 1990)
Animal
Chickens
Hogs
Beef cattle
Milk cows
Total Number
3,937,240
295,725
14,479
1,838
Number/km2
350.2
26.3
1.28
0.167
 Six waterbodies in the Tar-Pamlico basin are on the
 state's 1992 303(d) list (R. Swanek, North Carolina
 Division of Environmental Management, personal
 communication, August 9, 1993). The state is currently
 conducting several allocation studies that would qualify
 as TMDLs under section 303 (d).  Under North
 Carolina's new basinwide planning process, each major
 basin in the state comes up for review on a 5-year cycle.
 North Carolina plans to match the development of
 formal TMDLs with the basinwide planning cycle. The
 final basinwide plan for the Tar-Pamlico is due in
 August 1994.  The nutrient load reductions and
 allocation strategy on  which the Tar-Pamlico Nutrient
 Trading Program  is based will probably be submitted as
 a formal  TMDL after  the basin plan is complete.
ASSESSING AND CHARACTERIZING
THE PROBLEM

Nitrogen and phosphorus loading to the Tar and Pamlico
Rivers are the primary cause of degraded water quality
in the Pamlico River Estuary.  Nitrogen and phosphorus
are critical nutrients for algal growth and, in sufficient
quantities, support algal blooms that consume DO as
they decay (NCDEM, 1989).

A nutrient source budget (i.e.,  an accounting of the
magnitude of all nutrient sources in the watershed) was
prepared for the Tar-Pamlico basin in 1986. However,
two major events that have a significant impact on
present and future phosphorus budgets have occurred
since the budget calculations.  First, the North Carolina
General Assembly enacted a ban on the sale of
phosphate detergents.  Then, a new NPDES permit was
issued  to Texasgulf Industries,  Inc., a phosphate mining
operation whose total phosphorus loads accounted for 50
percent of the phosphorus budget for the entire basin.
After revising the budget for expected changes due to the
phosphate ban and the Texasgulf permit, the North
Carolina Division of Environmental Management
(NCDEM) estimated that approximately 66 percent of
the total phosphorus in the basin comes from nonpoint
sources. Approximately 25 percent comes from
WWTPs, and the remaining 9 percent comes from
Texasgulf Industries, Inc. Eighty-three percent of the
total nitrogen in the  basin comes from nonpoint sources,
primarily agricultural runoff and, to a lesser extent,
 urban runoff and atmospheric deposition (NCDEM,
 1989). Most researchers agree that nitrogen is the
 limiting factor for plant growth in the estuarine portion
 of the Tar-Pamlico basin (NCDEM, 1987).  The revised
 1988 nutrient budgets for the basin (after the phosphorus
 ban and the Texasgulf permit implementation) are
 summarized in Figure 3.


 MANAGING POLLUTANT LOADS

 The Initial Nutrient Control Strategy

 In April 1989 North Carolina's Environmental
 Management Commission designated the Tar-Pamlico
 basin as a Nutrient Sensitive Water (NSW).  Under
 provisions of state law,  this designation requires the
 development and implementation of a management
 strategy for both point and  nonpoint nutrient sources.

 The development of a comprehensive strategy for the
 Tar-Pamlico was complicated because the phosphate  ban
 and the new Texasgulf permit were enacted after the
 nutrient budgets had been calculated.  NCDEM was
 uncertain  about how much these changes would improve
 water quality; however,  because of continuing
 development, they could not afford to wait until all the
 necessary information had been obtained through
 research.  Consequently, the state proposed an interim
 strategy that required mandatory limits on nitrogen and
 phosphorus for new and expanding dischargers in the
 basin.  The aim of the strategy was to halt point source
 increases until a scientifically defensible nutrient
 reduction  plan could be designed and implemented.  The
 NSW strategy specified effluent concentration limits of 2
 mg/L for  total phosphorus throughout the year, 4 mg/L
 for total nitrogen in the summer, and 8 mg/L for total
 nitrogen in the winter.

 Dischargers in the basin responded to the state's initial
 strategy with concerns regarding the high costs of new
 facility construction to meet the nutrient control goals.
 The dischargers soon formed a coalition, the Tar-
 Pamlico Basin Association,  and began negotiations with
 the state, the  Environmental Defense Fund (NCEDF),
 and the Pamlico-Tar River Foundation. In 1989, the
 Association proposed a new strategy that allows for
 "nutrient trading" between point source dischargers and
 agricultural operations while meeting the overall nutrient
 reduction goal.

An Alternative Allocation Strategy—Nutrient
 Trading

 Under  the nutrient trading proposal, the Association
 contributes funding for agricultural best management
 practices (BMPs) in order to achieve all or part of the
 total nutrient reduction goals established for the member

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facilities. The underlying premise is that nutrient
reductions via BMPs can sometimes be more cost-
effective (on a per kilogram removal basis) than capital
outlays for new treatment facilities.  The Association
estimates that  controlling one unit of nonpoint source
loads with BMPs costs one-tenth as  much as controlling
the same load from a wastewater treatment plant (M.
Green, Tar-Pamlico Basin Association, personal
communication, July 30, 1993).

The nutrient trading proposal was approved by the North
Carolina Environmental Management Commission in
December 1989.  The program sets  up an overall
reduction goal and then allows nutrient sources to
find the most cost-effective way to allocate
allowable loads.   Polluters have the  flexibility to
trade reduction credits among themselves or to
pay to control pollution at other sources, such as
pig or chicken farms, as long as the total nutrient
limit for the basin is not exceeded (NCEDF,
1993).
           multiplying by a factor of 3 for cropland BMPs and by a
           factor of 2 for animal BMPs (NCDEM, 1992).
           IMPLEMENTING THE NUTRIENT
           TRADING PROGRAM

           Phase 1

           Implementation of the Nutrient Trading Program is being
           divided into phases. Phase 1 of the program will last 5
Determining Initial Load Reductions

NCDEM projected the 1994 flow for all the
municipal Association members at 30.55 million
gallons per day (mgd). Assuming no nutrient
reductions from pre-strategy conditions, NCDEM
estimated that total nutrient loading in 1994
would reach 625,000 kg/yr.  Under the original
NSW proposal, which required mandatory
phosphorus and nitrogen limits for point sources,
projected loadings for 1994 would decrease to an
estimated 425,000 kg/yr, a reduction of 200,000
kg/yr. Subsequently, NCDEM, the Association,
NCEDF, and the Pamlico-Tar River Foundation
together established 200,000 kg/yr as the
reduction goal for Phase 1 of the Nutrient
Trading Program. Of this, 180,000 kg/yr is for
nitrogen and 20,000 kg/yr is for phosphorus
(NCDEM, 1992). The program was a popular
solution because it fulfilled the state's NSW
reduction goals, addressed nonpoint source
concerns, and reduced the economic burden to
municipal dischargers.

Determining  Control Costs

The estimated cost of achieving the 200,000
kg/yr nutrient reduction goal using agricultural
BMPs alone was $11.8 million—$10 million on
the ground and $1.8 million in administration
(Harding, 1990). These values were determined
by multiplying the reductions by a factor of $56
per kg per year, the estimated cost for removing
 1 kg of nutrient per year using BMPs. The rate
was drawn from BMP funding experience in the
adjoining Chowan River basin. The calculation
of the cost factor included a margin of safety by
           1988 Revised Phosphorus Budget
                   Tar-Pamlico Basin
   WWTPs (25.2%)
   Urban (3.5%)

    Texasgulf Ind.
        (9.1%)
         Livestock 115.1%)
                                        Cropland (21.7%)
                                              Atm. Deposition
                                                  (5.5%)
                                          Forestry (19.9%)
                    1988 Nitrogen Budget
                      Tar-Pamlico Basin
                           Urban (3.6%)
       Forestry (21.4%) _-=^^^^~~^x.   Atm. Deposition
                                               (18.6%)
  Livestock (9.5%)
                                              WWTPs (14.9%)
                                          Texasgulf Ind.
                                              (2.0%)
                    Cropland (30.0%)
FIGURE 3. The 1988 nitrogen and phosphorus source budgets for the Tar-|
Pamlico Basin (NCDEM, 1989)

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years, during which time the trading approach will be
refined and evaluated.  As part of Phase 1, NCDEM
requires that the Association meet the following
conditions to maintain the nutrient trading option:

•   Develop an estuarine model

    The Association is funding the development of an
    estuarine model  to assess the relative importance of
    different nitrogen and phosphorus sources (i.e.,
    wastewater dischargers, nonpoint, sediment, and
    atmosphere) to algal growth and oxygen stress.
    This  three-dimensional model combines both
    hydrodynamic and water quality components to
    simulate DO depletion, algal growth,  concentrations
    of soluble and particulate nutrients, and several
    other parameters of concern. Recommendations for
    Phase 2 nutrient goals will be based on the results of
    this model.

 •  Evaluate existing wastewater treatment plants

    The Association hired a consultant to
    comprehensively analyze  the 12 participating
     municipal plants and to determine the changes
     needed to ensure that they are operating at the
     highest level of efficiency.  The municipalities will
     implement the operational and  minor capital
     improvements recommended by the consultant,
     attempting to achieve the original NSW effluent
     goals of 2 mg/L total phosphorus, 4 mg/L total
     nitrogen in summer, and 8 mg/L total nitrogen in
     winter.

 •   Fund the  design and administration of the Nutrient
     Trading Program

     The  Association will provide $150,000 over a
     2- year period to fund additional personnel in the
     North Carolina Division of Soil and Water
     Conservation (NCDSWC).  These  funds will be
     used to design and establish the nutrient trading
     system, including targeting and documenting BMP
     implementation.

  Ten of the 21 major municipal dischargers (design flow
  >0.1 mgd) in the Tar-Pamlico basin have joined the
  Association.  Two smaller municipal dischargers are also
  members. One industrial discharger is a member of the
  Association; however, its membership  includes an
  exemption from weekly monitoring provisions.
  Membership in the Association is voluntary, but if
  dischargers choose not to participate in the nutrient
  trading program they will be subject to the NSW
  nitrogen and phosphorus limits as  previously discussed.

  The Association has obtained an EPA grant to fund the
  development  of a nutrient management decision support
  system.   The system will use geographic information
system (GIS) technology to track monitoring
information, poinl: source loads, and BMP
implementation data.  The system will also incorporate a
watershed nutrient and sediment loading model based on
the Generalized Watershed Loading Functions (GWLF)
(Haith et al., 1992). The model will function as a tool
to assist in targeting subbasins for BMP implementation.
GWLF includes routines for calculating point source
loads, as well as dissolved- and solid-phase nonpoint
source loads  from rural, urban, and septic sources (RTI,
1992).

Under the Tar-Pamlico Nutrient Trading Program,
dischargers are free to trade reduction debits and credits
among themselves,  as long as the loading standards for
the basin are met,  This allows Association members to
maximize the cost-effectiveness of their operations.
However, the state  will continue to use individualized
permitting and  enforcement to control any localized
impacts that  may occur.  Nutrient trading avoids the
inefficiencies and costs associated with prescribing
controls for each discharger.

The opportunity to  develop and implement the Nutrient
Trading Program was made possible by the state's use of
the Basinwide Planning Process.  Under Basinwide
Planning, a basin is viewed as the basic unit for water
quality management,  allowing the State to evaluate and
address the primary causes of pollution hi a basin, as
opposed to consbintly traveling throughout the state to
 "put out fires."

Funding BMP Implementation and Maintenance

The Association payments go to the North Carolina
 Division of Soil and Water Conservation, which then
 distributes the  monies to the local soil and water
 conservation districts.  The conservation districts
 distribute the ftmds to BMP projects via the North
 Carolina Agricultural BMP Cost Share Program. At the
 District level, a ranking process is used to allocate cost-
 share funds  to agricultural'operations according to the
 severity of nutrient control problems.  NCDEM has set
 up a schedule for determining allowable nutrient loads
 and payments during Phase 1 (Table 2). If the total
 loads for the participating dischargers exceed the
 allowable load for  that year, the Association will pay an
 amount equal to $56 times the excess loading (kg).

 The results  of the  WWTP engineering evaluations
 indicate that a majority of the required nutrient
 reductions can be achieved through operational changes
 and minor capital  improvements. Consequently, the
 actual level of BMP funding is  likely to be substantially
 less than $11.8 million, which was estimated assuming
 all nutrient  reductions would be achieved via BMPs.

 To ensure the operation of the Nutrient Trading Program
 and the availability of funds, the Association has agreed

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 TABLE 2.  Schedule of Nutrient Loads and Payments (NCDEM, 1992; P. Blount, City of Rocky Mount, North Carolina,
 personal communication, August 10, 1993)
Calendar
Year
1991
1992
1993
1994
Allowable
Nutrient
Load (kg)
525,000
500,000
475,000
425,000
Actual
Nutrient
Load (kg)
455,685
422,962
n/a
n/a
Payment for
Exceeding
Allowable
Load ($)
0.00
0.00
n/a
n/a
Minimum
Payment*
($)
150,000
250,000
100,000
n/a
Report Results
March 1, 1992
March 1, 1993
March 1, 1994
March 1, 1995
Payment Due
September 30, 1992
September 30, 1993
September 30, 1994
September 30, 1995
 ' to ensure the operation of the Nutrient Trading Program
 to make yearly minimum payments to the trading fund
 (Table 2). These funds are in addition to the $150,000
 administrative payments and will be used to fund BMP
 implementation. For 1991 and 1992, the Association's
 total loading was less than the maximum allowable load.
 Consequently, the Association has paid the minimum
 each year. When calculating loading payments for a
 given year, the Association will receive credit for
 minimum payments made in prior years. All BMP
 credits will have a useful life of 10 years unless
 otherwise specified.

 Currently, NCDEM is conducting a pilot BMP project
 on Chicod Creek, a coastal plain tributary to the Tar
 River.  Chicod Creek has been identified by the state as
 severely impacted due to runoff from animal operations.
 The purpose  of the project is to quantify the
 effectiveness of various animal  waste management
 BMPs.  The  project is funded by EPA appropriations
 obtained through the efforts of the Association. The
 results of this study will provide important information
 on how BMP monies can be effectively targeted hi other
 portions of the Coastal Plain.

 Monitoring

 Since July 1991, Association  facilities have been
 performing weekly effluent monitoring for total
 phosphorus, total nitrogen, and flow.  The Association
 reports monitoring data to NCDEM annually.  NCDEM
 has developed a set of guidelines for estimating flow and
 concentration if this information is  not provided.

 Phase  2

 Phase 2 of the Tar-Pamlico Nutrient Trading Program
will be initiated in January 1995.  At that time, the
estuarine model will be complete and will be used to
determine nutrient reduction goals for the whole basin.
Essentially, Phase 2 will refine the simple loading
calculations that were conducted to set goals for the
initial phase of the project.  Details of this phase will be
 determined primarily by the success of Phase 1 and the
 results of the estuarine model.

 NCEDF has proposed wetlands restoration as a key
 strategy  in Phase 2 of the program; however, details
 regarding implementation of this strategy have not yet
 been defined.  Over the past 30 years, an  estimated 50
 percent of the Pamlico's wetlands have been destroyed.
 Wetlands control excessive nutrients by trapping
 pollutant-laden sediment, blocking erosion, lowering
 flood peaks, trapping nutrients in vegetation, and
 burying nutrients in soil.  On Chicod Creek, in addition
 to NCDEM's efforts, NCEDF is developing high-
 resolution maps  to pinpoint degraded wetlands and areas
 of major nonpoint source pollution. This information
 will be used to set priorities for restoring former
 wetlands based on their potential for reducing pollution
 (NCEDF, 1993).
CONSIDERATIONS

The Tar-Pamlico Nutrient Trading Program has largely
been the subject of praise from the state, dischargers,
and environmental groups.  By addressing nonpoint
sources,  the state and environmental groups have gained
a reduction program that is more comprehensive than the
original NSW strategy.  Dischargers are benefitting from
the increased flexibility and cost-effectiveness of the
trading approach.  However, Phase 2 will be met with a
number of challenges, including tracking compliance,
determining accountability,  and making sure that load
reductions are actually achieved.  The trading program is
designed so that once a discharger makes a trading
payment to the state for BMPs, its responsibility for that
share of pollutant reduction ends  for that year.  The $56
per kilogram per year trading factor is also a subject of
continued debate.  The technical basis for the value is
poorly documented and must be further validated.  In
addition, the plan does not include provisions for
escalating the factor due to inflation or other factors
(Woods, 1991).  The Association has applied for a
USDA grant to study BMP  effectiveness to address these

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challenges in Phase 2 (M. Green, Tar-Pamlico Basin
Association, personal communication, July 30, 1993).
REFERENCES

NCDA.  1990. North Carolina 1990 agricultural
statistics.  North Carolina Agricultural Statistics
Division, North Carolina Department of Agriculture.

NCDEM.  1987.  Surface water quality concerns in the
Tar-Pamlico River basin. North Carolina Division of
Environmental Management.  Report No. 87-04.

NCDEM.  1989.  Tar-Pamlico River basin nutrient
sensitive waters designation and nutrient management
strategy.  Water Quality Section, North Carolina
Division of Environmental Management.

NCDEM.  1992.  Tar-Pamlico NSW implementation
strategy.  North Carolina Division of Environmental
Management.

NCEDF.  1993.  Wetland restoration, non-point
pollution are the focus as Tar-Pamlico Project enters
 Phase II Planning.  In NCEDF Alert, Summer  1993.
 North Carolina Environmental Defense Fund.

 Haith, D.A. R. Mandel, and R.S.  Wu.  1992.
 Generalized watershed loading Junctions—Version 2.0:
 User's manual.  Department of Agricultural and
 Biological Engineering, Cornell University.
Harding, D.  1990.  Tar-Pamlico nutrient sensitive
waters management  strategy.  NWQEP Notes.  Number
44.  National Water Quality Evaluation Project.  North
Carolina Agricultural Extension Service.

RTL 1992.  Tar-Pamlico River basin nutrient
management decision support system:  Preliminary work
plan. Research Triangle Institute, Research Triangle
Park, NC.

Steel, J. 1990.  Albemarle-Pamlico estuarine system—
technical analysis of status and trends. Report 90-01.
Albemarle-Pamlico  Estuarine Study.

Woods, C.  1991.  Analysis of the nutrient sensitive
waters management strategy in the Tar-Pamlico river
basin.  Unpublished paper.
   This case study was prepared by Research Triangle
   Institute, Rese.«-ch Triangle Park, NC, in conjunction
   with USEPA, Office of Office of Wetlands, Oceans, and
   Watersheds, Watershed Management Section.  To obtain
   copies, contact: your EPA Regional 303(d)/TMDL
   Coordinator.

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