United States
            Environmental Protection
            Agency
               ERL-Narragansett
               South Ferry Road
               Narragansett Rl 02882-1198
               401 782-3000
EPA-600/8-89/084
ERL-N TT-02
November 1989
vvEPA
A Framework for
Real-Time
Decision-Making
            New  Bedford Harbor
            Pilot  Dredging Study
                        Pre-Operational Data
                             and
                        Site-Specific Criteria
                            Decision
                            Criteria
                           Committee
                     Operational
                     Data Analysis
                       Real-Time
                       Monitoring
                             Better
                       Environmental Decisions
                        U.S. Environmental Protection Agency
                        GLNPO Lil.jry Collection (PL-12J)
                        77 West Jackson Boulevard,
                        Chicago, II 60604-3590

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                                    PREFACE


   Numerical water quality criteria have  been employed by EPA in the

protection  of  the environment  for  decades.  Biological  tests and analytical

chemical procedures have  been  developed to assess the  state of environmental

quality based  on these  criteria. Numerous monitoring programs have been

implemented to collect  those data  necessary to make  decisions based on

criteria values.

   This technology transfer document provides an  overview of a unique project

that incorporates each  component listed above into a "real-time" decision

making framework. It was  successfully used in a pilot  study to determine

whether dredging posed  an "unacceptable"  hazard as a remediation option at the

New Bedford Harbor Superfund Site  in Massachusetts.  It represents a framework

that can be employed at other  locations to provide environmental protection

during clean-up operations.

   The successful completion of this project  is the  result  of a team effort of

over 80 individuals from  the Federal and  contract staff at  our laboratory,  as

well as EPA Region I, the U.S. Army Corps  of  Engineers, and the State of

Massachusetts' Department of Environmental  Protection. This effort was part of

a pilot study, therefore, any  comments, suggestions, or other input are

welcome.
                                     William G. Nelson, Ph.D
                                     Project Coordinator
                                     Environmental Research Laboratory
                                     Narragansett, RI 02882
                                        U.S. Enviror~        action Agency
                                        Region 5, Li:         . ••.}
                                        77 West Jack-... ^,,,,,/ard, 12th Floor
                                        Chicago, IL  60604-3590

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                                 INTRODUCTION
   New Bedford Harbor  (NBH)  is  located



along Buzzards Bay between the  cities



of New Bedford and Fairhaven,




Massachusetts (Fig.  1).  Since the




1940' s, electronics  and  manufacturing




companies in the area  have discharged



effluents containing polychlorinated



biphenyls (PCBs) into  the Acushnet



River and the harbor.  High PCS



concentrations in river  and  harbor




sediments were first documented  in 1974




(Connelly and St. John,  1988). Over the




past 15 years, nearly  18,000



acres of PCB- and heavy metals-
                                                                  •Long istanti SounO
                                                           UQOBT Bmzartt B«v
                                             '3 000  9.000 IM
                                                       FIGURE 1.



contaminated sediment have been  identified, with PCB concentrations as high as



100,000 parts per million (ppm)  in  some areas  of the upper harbor.  In 1982,



the site was added to the Environmental Protection Agency's (EPA) National



Priorities List of hazardous waste  sites  slated  for  cleanup under the



Super fund Act.



        A feasibility study conducted by  EPA in  1984 proposed several



alternatives for the remediation of NBH.  One option  common to most

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 remediation  alternatives  included dredging contaminated sediments out of the



 harbor.  Federal,  State, and  local officials,  as well  as the  public,  expressed



 concern  over dredging. Many  believed  that  sediments resuspended during



 dredging would cause  the  release  of contaminants  that would  affect biota



 inhabiting both the harbor and Buzzards Bay.  Others cited  potential  pollution



 problems from contaminated water  (leachate) leaking from the proposed disposal



 site  (Averett and Francigues, 1988).



    In order  to address these concerns, the EPA decided  to  pre-test dredging



 and possible disposal options. Working with the U.S.  Army  Corps of Engineers



 (COE), EPA Region I designed a pilot  study to examine dredging  as  a



 remediation  option for the Superfund  Site. A  monitoring plan (including



 biological,  chemical, and physical measurements)  for  all aspects of  the  Pilot



 Project  was  designed and implemented  by EPA's Environmental  Research



 Laboratory,  Narragansett, R.I. (ERL-N). This  technical  transfer document



 summarizes the decision-making process and the "real-time" monitoring data



 used  by  project managers to  assess the environmental  "acceptability" of  the



 dredging operation on a day-to-day basis.  Subsequent  publications will provide



 greater  detail of the monitoring  program with respect to evaluation  of



 dredging and disposal options.







                     PILOT DREDGING PROJECT DESCRIPTION







   The NBH Pilot Project was designed to examine and  compare the efficiency



 and effects  of three hydraulic dredges and two disposal methods  for use  in a



possible large scale remediation with more highly contaminated  sediment at the



NBH Superfund Site.  The COE selected dredges  capable  of removing sediment with

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minimal  resuspension as well as their ability to operate in the shallow water


at  the Pilot Study site. The two disposal methods investigated included: 1) a


confined disposal facility (CDF), which required construction of a containment


dike partially in-water and partially on land; and 2) a confined aquatic


disposal cell (CAD),  an in situ underwater disposal method (Otis,  1987).





                MONITORING STRATECT/PECISIOM-MAKING FRAMEWORK





    Evaluations of possible unacceptable contamination due to dredging during


the Pilot Study was complicated by the fact that Federal and State water


quality  standards for PCBs and certain heavy metals were exceeded in NBH under


preoperational baseline conditions.  In addition, the U.S. Food and Drug


Administration (FDA)  action level for PCBs in seafood was exceeded and


sediments were known  to be toxic.


    Because of these special conditions,  typical monitoring program and


management strategies were inappropriate.  Therefore, it was necessary to


develop  a unique  site-specific monitoring/management strategy for  NBH (Fig 2).


This framework included several

                                              Pro-Operational Data
unique aspects: 1)  the development                     I

           ,   .        .,.                        Decision Criteria
of  a set of  site-specific                               I


numerical  decision  values,  the            Decision  Criteria Committee   <*-


Decision Criteria,  2)  the             Construction/dredging Operational Data


establishment  of  a  panel of                Operational  Data Analysis

                                               (12-24 hr turnaround)
environmental  managers,  the                            A

                                              Environmental  Decision
Decision Criteria Committee (DCC),


to use those data in  a timely  manner,                FIGURE 2.

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provide  the necessary  environmental  data  to  the  DCC  in  a  rapid time-frame  (12-




24 hours). This approach provided an effective feedback loop  to evaluate,




modify or terminate  the dredging operation if environmental risks were




unacceptable.



   Each  aspect of this strategy was  successfully implemented.  The site-



specific Decision Criteria were established  for  a number  of physical,



chemical, and biological parameters  based on data collected prior to  the



initiation of dredging. The DCC was  formed with  representatives from  each  of




the principal parties  involved in the study: EPA Region I, COE,  Massachusetts



Department of Environmental Protection, and  ERL-N. A monitoring plan was




developed to collect samples during  the dredging and disposal  operations,



complete sample analysis within 24 hours, and compare those results to the



Decision Criteria values. If the Decision Criteria values were  exceeded, the



DCC could require engineering corrections to the  dredging operation before



work was resumed, or termination of  the project  if environmental effects were



judged excessive. The  Pilot Project was completed successfully  and




environmental risks minimized by modification of  dredging activities whenever



transitory increases above Decision Criteria values were detected.








                               MONITORING PLftN








   The philosophy adopted by the DCC during this project was that some "short-



term environmental impact was worth long-term improvement in water quality."



Station  locations for  the Decision Criteria were  selected to reflect this



principle.  Some short-term minor increases in water chemical concentrations



and chronic biological impacts in the immediate vicinity of the dredging

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and chronic biological impacts in the immediate vicinity of the dredging
operation, at Station NBH-2, were considered acceptable. However, any far-
field impacts affecting Buzzards Bay were deemed not acceptable. This was
accomplished by including a second strategic station at the Hurricane Barrier,
Station NBH-4, representing the transition between NBH and Buzzards Bay.
   The Pilot Project employed a suite of biological, chemical, and physical
monitoring techniques used at ERL-N. The biological procedures ranged from the
short-term acute and chronic methods used in the Complex Effluent Toxicity
Testing Program (CETTP) (US EPA, 1988) to in situ mussel deployments (Nelson,
et al., 1987). Before any operations were begun by the COE, baseline physical,
chemical, and biological measurements were completed.  The biological
measurements were used to assess the effects of existing water quality on
plant and animal survival, growth, and reproduction. These tests served as a
benchmark against which increased contamination and/or toxicity associated
with the operational phases of the study were compared.
   Five stations were selected for
water quality monitoring,  four in NBH,
and  a reference station in Buzzards
Bay (Fig 3). Station NBH-1
was located north of the dredge
site; Station NBH-7 was adjacent
to the cove where dredging
occurred; Station NBH-2 was at the
Coggeshall St.  Bridge,  the
transition point between the more
severely polluted upper harbor and
NEW BEDFORD HARBOR
           FIGURE 3.

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point between NBH proper and Buzzards Bay.



   The reference station for all water quality toxicity tests was



NBH-5, located at West Island in Buzzards Bay. Mussels were deployed at




stations NBH-2, NBH-3, NBH-4, and NBH-5. Only two of these stations, NBH-2 and



NBH-4, were used in the Decision Criteria because of their strategic



locations.



   Seawater samples were collected separately for the ebb and flood tide at



each NBH station. Flow proportional collections at NBH-2 allowed estimation of




net transport. Each water sample was analyzed for total suspended solids,




PCBs, copper, cadmium, and lead. In addition, biological measurements were



completed including acute toxicity tests (survival of fish, mysids, mussels, a



red alga, and the sea urchin sperm cell fertilization test) and chronic



toxicity tests (fish growth, mysid growth and reproduction, mussel scope for



growth, and algal reproduction).



   Once the operational phases of the Pilot Project began, water samples were




collected identical to those of the preoperational phase, however, the ebb



tide samples were returned to ERL-N immediately,  and chemical analyses and



acute biological tests were completed overnight.  These results were



transmitted to the Decision Criteria Committee prior to the start of that



days' dredging to assess any adverse environmental impacts and make any



necessary adjustments to the operation.  This "real-time" monitoring allowed



the managers of this project to make timely decisions based on actual data,



thus ensuring the best degree of environmental protection possible.

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                              SUMMARY OF RESULTS
   Total PCD (>
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exceeded at NBH-2, however, because  this occurred during  the  same  storm it was




judged not to be related to the operation.




Mussel Chemistry.  Mussels deployed  in NBH showed a distinct  spatial and



temporal pattern with  respect to PCB uptake. The PCB concentrations in  mussel



tissues from the preoperational deployments were highest  in the upper harbor



(NBH-2) and decreased  moving down the harbor (NBH-4). PCB tissue




concentrations also increased with length of exposure. Concentrations of PCBs



in mussel tissues during the operational phases were not  significantly




elevated, indicating no increased bioavailability of PCBs due to the dredging



operation.



Biological Tests.  The short-term biological tests employed in this project



demonstrated sporadic  toxicity immediately adjacent to the dredging area



(NBH-7). Reproduction  in the red alga, Champia parvula, was consistently




reduced and on one occasion fertilization was reduced in  the sea urchin



(Arbacia punctulata) sperm cell test. No effects were detected on growth or



survival in the sheepshead minnow,  Cyprinodon variegatus, or on growth or



reproduction of the mysid,  Mysidopsis bahia.  The SFG of mussels never exceeded



the Decision Criteria values.  The acute and chronic toxicity tests indicated



no unacceptable biological impacts from this project.

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                                 CONCLUSIONS
   The New Bedford Harbor Pilot Dredging Project demonstrated the utility of



biological, chemical, and physical monitoring techniques to evaluate, on a



"real-time" basis, the environmental risks of a dredging operation. A set of




site-specific criteria were developed and utilized by environmental managers



to assess, on a day-to-day basis, the impacts of this dredging operation on




water quality in NBH.



   Monitoring data indicated that the dredging operation had a minimal effect



on existing water quality. On those occasions when elevated PCB concentrations



were detected, they were attributed to a specific causative operational



procedure or meteorological event. Operational modifications were implemented



effectively, thus limiting any environmental damage.



   It would be unrealistic to expect to complete a Superfund remediation at



an aquatic site with absolutely zero short-term impact. However, this program



successfully established a set of limits (Decision Criteria) beyond which the



impact was considered unacceptable, and a mechanism (real-time monitoring




program) which provided the information necessary for environmental managers



(Decision Criteria Committee) to effectively oversee this project to



completion.

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                                      References
Averett, D.E. and N.R. Francingues, Jr. 1988. A case study: dredqing as a
remedial action alternative for New Bedford Harbor, Massachusetts. Superfund
'88. Proceedings of the 9th National Conference. The Hazardous Materials
Control Research Institue, pp 338-342.

Connelly, J.P. and J.P. St. John. 1988. Application of a mathematical food
chain model to evaluate remedial alternatives for PCB-contaminated sediments
in New Bedford Harbor, Massachusetts. Superfund '88. Proceedings of the 9th
National Conference. The Hazardous Materials Control Research Institue, pp
359-362.

Nelson, W.G., O.K. Phelps, W.B. Galloway, R. Pruell, and P. Rogerson. 1987.
Effects of Black Rock Harbor dredged material on the scope for growth of the
blue mussel, Mytilus edulis, after laboratory and field exposures. Technical
Report D-87-7. Prepared by the U.S. EPA Environmental Research Laboratory,
Narragansett, R.I. for the  U.S. Army Corps of Engineers Waterways
Experimental Station, Vicksburg, MS.

Otis, M.J. 1987. Pilot study of dredging and dredged material disposal
alternatives. Draft. U.S. Army Corps of Engineers, New England Division,
Waltham, MA.

Otis, M.J. and D.E. Averett. 1988. Pilot study of dredging and dredged
material disposal methods, New Bedford Harbor, Massachusetts Superfund Site.
Superfund '88. Proceedings of the 9th National Conference. The Hazardous
Materials Control Research Institue, pp 347-352.

U.S. Environmental Protection Agency. 1988. Short-term methods for estimating
the chronic toxicity of effluents and receiving waters to marine and estuarine
organisms. US EPA Environmental Research Laboratory, Cincinnati, OH.  EPA
600/4-87/028
                                     10

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U.S. Environmental  Protection Agency
GLNPO Library Collection (PL-12J)
77 West Jackson Boulevard,
Chicago, IL  60604-3590


U.S.
Region 5, '
77 V/~-s-  <-• •
9 I 1*^Ji w
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