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Proceedings of the Seventeenth
Annual Aquatic Toxicity
Workshop: November 5-7,
1990, Vancouver, B.C. Vol. 1
Comptes rendus du dix-septidme
colloque annuel sur latoxicologie
aquatique : 5-7 novembre
1990, Vancouver, (C.-B.) vol. 1
Editors/£diteurs
P. Chapman, F. Bishay, E. Power, K. Hall,
L. Harding, D. McLeay, M. Nassichuk and/et W. Knapp
rebruary 1991
Fevrier 1991
Canadian Technical Report of
Fisheries and Aquatic Sciences
No. 1774 (Vol. 1)
Rapport technique canadien
des sciences halieutiques et
aquatiques n° 1774 (vol. 1)
¦ ^ ¦ Fisheries P6ches
1^1 and Oceans et Oceans
Canada

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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before complet.
1. REPORT NO. 2.
EPA/600/A-94/002
3.
4. TITLE AND SUBTITLE
AN APPLICATION OF "REAL-TIME MONITORING IN DECISION
MAKING:THE NEW BEDFORD HARBOR PILOT DREDGING PROJECT
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
William G. Nelson
8. PERFORMING ORGANIZATION REPORT NO.
ERLN-1197
9. PERFORMING ORGANIZATION NAME AND ADDRESS
US EPA Environmental Research Laboratory
27 Tarzwell Drive
Narragansett, RI 02882
10. PROGRAM ELEMENT NO.
1 1. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
Peer Reviewed Proceedings
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
Proceedings of the. 1.7th Annual Toxicology Workshop Vancouver, BC. Canadian Technical
Report Fisheries and Aquatic Sciences 1991 1(1774):76-69.
16. ABSTRACT
A decision-making framework was established for assessing the impacts of a
pilot dredging study at the New Bedford Harbor, MA, Super fund site. Concern
over possible environmental impacts due to dredging at this site necessitated
that a monitoring program be implemented to ensure that unacceptable water
quality impacts did not occur during this project. Consequently, criteria were
derived, a management committee assembled, and a "real-time" monitoring plan
designed. Because many existing chemical concentrations in the water column
and indigenous biota exceeded Federal and state water quality limits, site-
specific chemical and biological criteria were established. A committee of
environmental managers from Federal and state government was established with
the authority to assess and modify the operation on a daily basis. Finally, a
"real-time" monitoring plan was implemented in which water samples were
collected, analyzed within 16 hours, and the data supplied to the management
committee in order to assess the environmental impact of the previous days'
operation. The combined use of site-specific criteria and a "real-time"
decision making management process allowed for successful completion of this
project with a minimal effect on water quality.
!7. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. cos at i Field/Group
Dredging Project indigenous biota
New Bedford Harbor
Monitoring
Decision Making
assessing impacts
Super Fund site
water samples


18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (This Report)
UNCLASSIFIED
21. NO. OF PAGES
4
20. SECURITY CLASS (This page)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (Rev. 4-77) previous edi tion i s o esolete

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EPA/600/A-94/002
76
AN APPLICATION OF "REAL-TIME" MONITORING IN DECISION MAKING:
THE NEW BEDFORD HARBOR PILOT DREDGING PROJECT
William G. Nelson
Environmental Protection Agency
Environmental Research Laboratory
27 Tarzwell Drive
Narragansett, RI 02882
ABSTRACT
A decision-making framework was established for assessing the impacts of a
pilot dredging study at the New Bedford Harbor, MA, Superfmid site. Concern
over possible environmental impacts due to dredging at this site necessitated
that a monitoring program be implemented to ensure that, unacceptable water
quality impacts did not occur during this project. Consequently, criteria were
derived, a management committee assembled, and a "real-time" monitoring plan
designed. Because many existing chemical concentrations in the water column
and indigenous biota exceeded Federal and state water qualify limits, site-
specific chemical and biological criteria were established, A committee of
environmental managers from Federal and state government was established with
the authority to assess and modify the operation on a daily basis. Finally, a
"real-time" monitoring plan was implemented in which water samples were
collected, analyzed within 16 hours, and the data supplied to the management
committee in order to assess the environmental impact of the previous days'
operation. The combined use of site-specific criteria and « "real-time"
decision making management process allowed for successful completion of this
project with a minimal effect on water quality.
EXTENDED SUMMARY
New Bedford Harbor (NBH) is located along Buzzards Bay between the cities
of New Bedford and Fairhaven, MA. Since the 1940's, electronics and
manufacturing companies in the area have discharged effluents containing
polychlorinated biphenyls (PCBs) into the harbor. High FCB concentrations in
harbor sediments were first documented in 1974 (Connelly and St. John, 1988),
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 Superfund Act.
A feasibility study conducted by EPA in 1984 proposed several alternatives
for the remediation of NBH. One option common to most remediation alternatives
was the dredging of contaminated sediments. Federal, state, and local
officials, as well as the public, expressed concern that the resuspension of
sediments during dredging may cause the release of contaminants that would
affect biota at more distant areas in the harbor and Buzzards Bay. Others
cited potential pollution problems from contaminated water (leachate) leaking
from the proposed disposal site (Averett and Francigues, 1988).

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In order to address these concerns, EPA Region I, in conjunction with the
U.S. Array Corps of Engineers (COE), initiated the NBH Pilot Dredging Project
to establish the impacts of various dredging and disposal options on a small
scale with relatively low (with respect to NBH) contaminated sediments (PCB
concentrations approximately 100 ppm). Information derived from this project
would be used to determine the most environmentally safe methods for use in a
possible large scale remediation of the most contaminated areas of the NBH
Superfund Site.
The overall goal of the Pilot Project was to determine the feasibility of
various dredging and disposal options for removing and sequestering highly
contaminated sediments in NBH. This included assessing whether or not it was
practical from an engineering perspective, as well as determining if the
operations could be completed without causing unacceptable environmental
impacts. The engineering aspect of the project assessed three shallow-water
dredges capable of removing sediment with minimal resuspension. In addition,
two disposal methods were evaluated: 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). The results of these engineering
operations are reported elsewhere (Otis, 1989).
A second objective implicit in the overall goal was to determine whether
the engineering operations could be completed in such a manner as not to cause
unacceptable damage to the environment. The decision-making process used to
assess the environmental acceptability of this project is the topic of this
summary.
Because of the high PCB concentrations in the sediments to be dredged
during the Pilot Project (100 ppm), it was necessary to make rapid assessments
as to the environmental "acceptability" of the operations. The evaluation of
possible unacceptable contamination of the water column due to dredging during
the Pilot Project was complicated by the fact that Federal and State water
quality standards for PCBs (U.S. EPA, 1980) and certain heavy metals (U.S.
EPA, 1985) were exceeded in NBH under preoperational baseline conditions. In
addition, the U.S. Food and Drug Administration (FDA) action level for PCBs in
seafood in NBH was exceeded (Kolek and Ceurvels, 1981).
These special conditions necessitated the development of a distinctive
site-specific monitoring/management strategy for the Pilot Project. This
framework included several unique aspects: 1) development of a set of site-
specific Decision Criteria for assessing water and tissue chemical
concentrations and biological effects, 2) establishment of a panel of
environmental managers, Decision Criteria Committee, to use those data in a
timely manner, and 3) design and implementation of a monitoring program to
provide the necessary environmental data to the Committee in a rapid time-
frame (12-24 hours). This approach provided an effective feedback loop to
evaluate, modify or terminate the dredging operation if the Decision Criteria
were exceeded.
Each aspect of this strategy was successfully implemented. First, site-
specific Decision Criteria were established at two strategic locations within
the harbor. The philosophy adopted for establishing criteria values was that

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short-term, near-field elevations in contaminant concentrations or biological
effects would be evaluated against long-term improvements in water quality,
provided that no far-field effects were observed. Using this rationale,
criteria were established for a number of physical, chemical, and biological
parameters based on data collected prior to the initiation of dredging (Nelson
and Hansen, in press).
Secondly, a Decision Criteria Committee was formed with representatives
from each of the major participants involved in the study: EPA Region I, the
COE, the Massachusetts Department of Environmental Protection, and EPA's
Environmental Research Laboratory, Narragansett, RI (ERL-N). This committee
was empowered to make decisions on a daily basis if there were impacts
attributable to the operation. Possible corrective actions to limit adverse
effects due to the project ranged from altering operational procedures to
temporarily halting the operation or termination of the study.
Finally, a monitoring plan was developed and implemented by ERL-N to
collect samples during the operational phases of the project, complete sample
analysis within 24 hours, and transmit the resultant information to the
Committee for comparison with the Decision Criteria values.
The chemical and biological monitoring data indicated that the dredging
operation had a minimal effect on existing water quality; the only criterion
exceeded was PCB water concentration. On the four 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 elevations in water column PCB
concentrations.
It may 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: dredging 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.
Kolek, A. and R. Ceurvels. 1981. Polychlorinated biphenyl (PCB) analysis of
marine organisms in the New Bedford area, 1976-1980. 29 p. in Commonwealth of
Massachusetts, Division of Marine Fisheries. Publication No. 12265-36-100-1-
81-CR.
Nelson, W.G. and D.J. Hansen. In press. Development and use of site-specific
chemical and biological criteria for assessing the New Bedford Harbor Pilot
Dredging Project. Environmental Management.
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. 1989. New Bedford Harbor Superfund Pilot Study: Evaluation of
dredging and dredged material disposal. Interim Report. U.S. Army Corps of
Engineers, New England Division, Waltham MA.
U.S. EPA. 1980. Ambient Water Quality Criteria for Polychlorinated Biphenyls.
EPA 440/5-80-068, 197 pp.
U.S. EPA. 1985. Ambient Water Quality Criteria for Copper - 1984. EPA 440/5-
84-031, 142 pp.

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