Contaminated Sediments
United States Environmental
Protection Agency |
Office of Water (4305 ) | EPA-823-N-97-006 Number 19 Summer 1997
|
EPA Great Lakes National
Program Office Publishes a Series of Articles on the Assessment and
Remediation of Contaminated Sediments (ARCS) Program
Fourteen papers published in the Journal of Great Lakes Research, volume 22(3),
report the results of the recently completed Assessment and Remediation of Contaminated
Sediments (ARCS) program (Fox and Tuchman, 1996).
The ARCS program was established to help address the contaminated sediment problem at 42
Great Lakes Areas of Concern (AOCs). The program was enacted under Section 118(c)(3) in the
1987 re-authorization of the Clean Water Act and administered through the U.S. EPA Great
Lakes National Program Office (GLNPO).
The objectives of the ARCS program were to: (1) assess the nature and extent of sediment
contamination at AOCs; (2) demonstrate and evaluate remediation options; and (3) provide
guidance on contaminated sediment problems and remediation alternatives at AOCs and other
locations in the Great Lakes (U.S. EPA, 1994a,b).
Volume 22(3) of the Journal of Great Lakes Research contains papers developed
from activities of the Toxicity Chemistry Workgroup and the Risk Assessment and Modeling
Workgroup in the ARCS program. An introductory chapter by Fox and Tuchman describes the
ARCS program. A paper by Burton et al. provides a comprehensive evaluation of a number of
different toxicity tests and compares factors such as similarity, redundancy, and selectivity among
these tests.
The next paper, by Smith et al., discusses long core sampling using a vibro-corer.
Rathburn et al. then address indicator and screening analyses for inexpensive and quick estimates
of sediment toxicity. Ankley et al. report on toxicity identification evaluations (TIEs) of
pore-water samples.
Hall et al. then evaluate the utility of algal toxicity tests. Papoulias et al. and
Papoulias and Buckler discuss optimization of Ames mutagenicity assays for assessing sediments.
Four other papers describe approaches for integrating sediment toxicity, chemistry, and benthic
community data. Canfield et al. reported results of benthic community assessments and
the sediment quality triad while Swift et al. compared those results to benthic
communities sampled with artificial substrates.
Ingersoll et al. and Smith et al. calculated and evaluated sediment effect
concentrations including ERLs (Effect Range Low), ERMs (Effect Range Median), TELs
(Threshold Effect Levels), and PELs (Probable Effect Levels). Three final papers evaluate
modeling and risk assessment procedures including the use of ranking procedures by
Wildhaber et al., transport of contaminated sediments in the Saginaw River by Cardenas
and Lick, and baseline human health risk assessments by Crane.
Major findings and recommendations of these studies include: (1) the use of integrated
assessment procedures which incorporate chemical analyses, toxicity tests, and benthic community
assessments, (2) screening level analyses to efficiently analyze large numbers of samples, (3) three
dimensional assessments to determine spatial variation in sediment contamination, and (4)
sediment effect concentrations and ranking procedures to help integrate data generated in
ecological risk assessments of contaminated sediments. GLNPO has prepared two additional
technical guidance documents which summarize information learned in the ARCS program (U.S.
EPA 1994a,b).
References Cited
Fox, R.G., and M. Tuchman. 1996. The assessment and remediation of contaminated
sediments (ARCS) program. J. Great Lakes Res. 22:493-494.
U.S. Environmental Protection Agency. 1994a. ARCS assessment guidance document. EPA
905-B94-002, Chicago, IL.
U.S. Environmental Protection Agency. 1994b. ARCS risk assessment and modeling
overview document. EPA 905-R94-003, Chicago, IL.
For additional information on these publications, please contact Callie Bolattino, U.S. EPA,
GLNPO, 77 W. Jackson, Chicago, IL (312/353-3490, fax -2018; e-mail
bolattino.callie@epamail.epa.gov).
FOCUS
Environment Canada
Canadian Sediment Quality Guidelines
Environment Canada (Guidelines Division, Science Policy & Environmental Quality Branch)
develops Canadian sediment quality guidelines for the protection of aquatic life as part of its
obligations under the Canadian Environmental Protection Act (CEPA).
The Act dictates the Canadian government s responsibilities regarding monitoring activities,
substance assessments, pollution prevention and control strategies, and regulatory activities (e.g.,
ocean disposal of dredged sediments). These national sediment quality guidelines are developed
cooperatively with the provincial and territorial governments through the Water Quality
Guidelines Task Group of the Canadian Council of Ministers of the Environment (CCME).
CCME is a joint federal, provincial, and territorial council committed to intergovernmental
cooperation on environmental matters in Canada.
National sediment quality guidelines for chemical substances, which are developed using
toxicological information, represent concentrations of individual chemicals below which adverse
biological effects are not expected. They are developed with the intention to be conservative,
national benchmarks (i.e., reference points) to protect and sustain aquatic life. These resource-use
based guidelines provide scientifically defined measures to evaluate the status of, and progress
toward, societal goals for the maintenance, protection, and remediation of environmental quality
(Gaudet et al. 1995).
Although Canadian sediment quality guidelines provide a nationally consistent, scientific basis
for management decisions, such as the development of substance-, site-, or issue-specific
objectives or standards, they do not directly incorporate management considerations (e.g., cost
and technological limitations) nor are they intended to serve directly as management objectives
without due consideration of such factors. Therefore, effective implementation of national
sediment quality guidelines requires that the distinction between generic guidelines and
site-specific objectives be recognized within a broader decision-making framework.
In Canada, sediment quality guidelines are developed using a nationally approved protocol
(CCME 1995) to ensure consistency, transparency, and scientific defensibility in the process.
Sediment quality guideline technical documents for a number of individual chemicals and groups
of substances are being developed by the Environment Canada Guidelines Division. The
document Canadian Sediment Quality Guidelines for Cadmium should be available in
early 1997. The draft Environment Canada document, Proposed Interim Canadian Sediment
Quality Guidelines for the Protection of Aquatic Life, will be available once an internal
Departmental review is complete.
For more information, contact Sherri Smith (819 953-3082; sherri.smith@ec.gc.ca) or Karen
Keenleyside (819-997-4070; karen.keenleyside@ec.gc.ca) at Environment Canada.
References Cited
CCME (Canadian Council of Ministers of the Environment). 1995. Protocol for he
Derivation of Canadian Sediment Quality Guidelines for the Protection of Aquatic Life.
Report CCME EPC-98E. Prepared by the Technical Secretariat of the Water Quality Guidelines
Task Group, Winnipeg, Manitoba. 38 p.
Gaudet, C.L., K.A. Keenleyside, R.A. Kent, S.L. Smith, and M.P. Wong, 1995. How should
numerical criteria be used? The Canadian approach. Human and Ecological Risk
Assessment 1(1): 19-28.
HEADQUARTERS ACTIVITIES
Status of EPA-OST Sediment Documents
|
Editor's Note: EPA's Office of Science and Technology
within the Office
of Water
and EPA Labs within
the Office of Research and Development continue to develop documents about sediment criteria,
management,
implementation guidance, assessment, and models. Some documents are in planning stages, while
others are very
near completion. The status and description of these documents is provided in this
table. |
Document
Title |
Description |
Status
|
Users Guide for
Multi-Program
Implementation of Sediment
Quality Criteria |
Guidance on use of SQC in water quality standards
programs, NPDES permitting, and TMDLs. Also
includes discussion of how SQC might be used in other
agency programs (e.g., CERCLA, RCRA). Contacts:
Jane Farris 202-260-8897, or Ross Elliott 202-260-1311 |
Draft scheduled for Fall
1997. |
Sediment
Quality Criteria (SQC) for
dieldrin and endrin |
Criteria document explains derivation of criteria for
dieldrin and endrin. Reflects comments received in
response to proposed criteria. Contacts: Mary Reiley
202-260-8897, Heidi Bell 202-260-5464 |
Final scheduled for Fall
1997. |
SQC Technical
Basis Document (TBD) for
Deriving SQC for Nonionic
Organic Contaminants for
the Protection of Benthic
Organisms by Using EqP
|
This document will be the fundamental source describing
how SQC (overall) are derived, and will reflect public
comment received in response to draft TBD. Contacts:
Mary Reiley202-260-9456, Heidi Bell 202-260-5464
|
Final scheduled for Fall
1997. |
SQC Site-Specific Document for
Nonionic Organic
Contaminants |
Document will provide the tools and algorithms for
States and tribes to modify the sediment quality criteria
that they adopt into their State/Tribal standards, and will
reflect public comment received in response to draft
Site-Specific Document. Contacts: Mary Reiley 202-260-9456, Heidi Bell 202-260-5464 |
Final scheduled for Fall
1997. |
Technical
Document: Models for
Sediment Quality-Based
NPDES Permitting |
Describes the technical aspects of applying existing
hydrodynamic/water quality models for the development
of sediment quality-based NPDES permits. The
document discusses underlying theory, model
classification, and applications to different environmental
settings. Contact: Bill Tate 202-260-7052 |
Draft scheduled for
Winter
1998. |
Volume 1: Draft
National Sediment Quality
Survey; Volume 2: Data
Summary for Areas of
Probable Concern (APCs);
Volume 3: Sediment
Contaminant Point Source
Inventory; and Volume 4:
Sediment Contaminant
Nonpoint Source Inventory
|
Report to Congress required under the Water
Resources Development Act of 1992. Act required that
EPA, in consultation w/ NOAA and COE, conduct a
comprehensive national survey of data regarding
sediment quality; identify location of sediments that are
contaminated and probable sources of pollutants; report
to Congress the findings, conclusions, and
recommendations every 2 years; and develop a system to
manage, store, disseminate sediment quality data.
Contact: Jim Keating 202-260-3845 |
Final Volumes 1 -
3 scheduled for Fall
1997. Volume 4 is
under
development. |
Draft EPA
Protocol for Collecting,
Spiking, Handling, &
Manipulating Sediment
Samples |
Describes Agency standard field protocols for
sediment sampling, handling, spiking and manipulation.
Contact: Bill Tate 202-260-7052 |
Draft scheduled
for Winter
1998. |
EPA's
Contaminated Sediment
Management Strategy |
Describes EPA's understanding of the extent and
severity of sediment contamination, including
uncertainties about the problem; describes the cross-program policy framework in which EPA
intends to
promote consideration and reduction of ecological and
human health risks posed by sediment contaminants; and
describes actions EPA believes are needed to bring
about considerations and reduction of risks posed by
contaminated sediments. Contact: Jane Farris 202-260-8897 |
Final scheduled
for Fall
1997. |
Evaluation of
Dredged Material Proposed
for Discharge to Inland
Waters of the United States -- Testing Manual Joint EPA-OST and U.S. Army Corps
of Engineers Document
|
Provides a national testing framework which
comprises one element of an overall decision-making
process for determining whether dredged material can be
discharged into CWA Section 404 waters. The manual
provides consistency between dredged material
evaluations under CWA and MPRSA. Regional
flexibility is allowed within this national framework.
Contact: Mike Kravitz 202-260-8085 |
Draft released for
Public Comment in June
of 1994. Final
Publication date to be
announced. |
Public Outreach
Materials: Contaminated
Sediment Information for a
Pamphlet and Display
|
The pamphlet and display will educate the public
including citizens groups and high school students on the
definition and extent of contaminated sediment, sources
of contamination, remediation and pollution prevention
solutions, and what the citizen can do to protect
sediment. Contact: Jane Farris at 202-260-8897. |
Final scheduled
for Fall
1997. |
Bioaccumulation
Testing and Interpretation of
Sediment Quality
Assessment: Status and
Needs |
Provides background information and reports on
the status of bioaccumulation testing and interpretation in
various EPA and other Federal Agency Programs for the
purpose of sediment quality assessment. Contact: Mike
Kravitz at 202-260-8085. |
Final scheduled
for Fall
1997. |
Standard
Methods for assessing
chronic sediment toxicity to
benthic organisms |
Standard methods under development for chronic
sediment toxicity tests using Hyalella, Chironomus, and
Leptocheirus. Contact: Leanne Stahl at 202-260-7055
|
Final scheduled
for Winter 1998. |
REGIONAL ACTIVITIES
Region 1
EPA Proposes Cleanup Plan for Upper and Lower New Bedford, Mass. Harbor
After extensively studying the 18,000-acre New Bedford Harbor Superfund Site, EPA
recently proposed a remedy that includes dredging 170 acres of PCB-contaminated sediments in
upper and lower New Bedford Harbor and isolating the sediments in confined disposal facilities
(CDFs).
From the 1940's through the late 1970's, factories near New Bedford Harbor, a tidal estuary
on Buzzards Bay in southeastern Massachusetts, discharged PCB-containing industrial process
wastes into the harbor and New Bedford's sewerage system. EPA discovered widespread PCB
and heavy metal contamination in the sediments and marine life throughout Buzzards Bay, and in
1977 the Massachusetts Department of Public Health issued a warning and closed areas of the
harbor and bay to fishing. In 1982 EPA added the New Bedford Harbor Site to the National
Priority List of sites eligible for Superfund cleanup funds. Massachusetts has designated the New
Bedford Harbor site as its top priority federal Superfund site.
The Proposed Cleanup Plan
EPA proposes to design and build four shoreline CDFs and associated water treatment
facilities. The CDFs would be built in contaminated areas to avoid dredging approximately
126,000 cubic yards of underlying contaminated sediment. Dredged contaminated sediments
would be piped into the CDFs and passively dewatered. Groundwater monitoring wells would be
installed around each CDF to verify that it is operating safely.
Once construction of the first CDF is complete, dredging would commence. Approximately
450,000 cubic yards of PCB-contaminated sediment are to be dredged: in the upper harbor,
sediments above 10 parts per million (ppm) PCBs would be dredged; and in the lower harbor and
salt marsh areas, sediments containing more than 50 ppm PCBs would be dredged. Sediments
above the target cleanup levels would be removed from the river bottom by a cutter head dredge,
a type of dredge proven to be environmentally safe. The sediments would then be pumped by the
dredge to one of the four CDFs. Other dredging methods may be used for deep water or salt
marshes.
The air quality in nearby residential areas would be monitored throughout the dredging
process, and a minimum of 2 feet of water would be maintained above the sediment during
dredging operations to control airborne PCB emissions. Similarly, the water column would be
sampled during dredging to ensure that sediment resuspension is below pre-established safe levels.
During dredging, seawater would be drained from the sediments and treated physically and
chemically to reduce levels of PCBs and heavy metals before discharge back into the harbor.
After the CDFs are filled with sediment, a preliminary cap would be installed to prevent
escape of PCB dust and to allow for precipitation runoff while the underlying contaminated
sediment consolidates. This consolidation process, which is expected to take approximately 3
years, is necessary to establish appropriate foundation conditions prior to construction of a final
impermeable cap. When the dredged sediment has sufficiently consolidated, a multi-layered cap
would be constructed to prevent water infiltration into, and promote surface drainage away from,
the underlying sediments.
EPA plans to work with local communities to develop appropriate plans for beneficial reuse
of each CDF. For example, the City of New Bedford has expressed an interest in reusing one CDF
as a commercial marine facility. As a result, the CDF could be designed with walls on the seaward
side to promote docking and with a footprint that would accommodate future boat-hauling
activities. Design accommodations also can be made to the other CDFs, provided that the ultimate
land use is developed in advance and in conjunction with the surrounding towns.
Proposed Remedy Enhancement to Include Navigational Dredging
The Commonwealth of Massachusetts has requested an enhancement of the Superfund
remedy to include dredging and disposal of an additional 1 million cubic yards of sediments
generated from the maintenance dredging of navigational channels. Although these "navigational"
sediments fall below the proposed target cleanup levels for PCBs, and thus do not overlap with
the sediments slated for Superfund dredging, they are still contaminated with metals and low
levels of PCBs. As a result, disposal options are limited, and an alternative disposal plan is
required if the harbor shipping channels are to be maintained at their originally approved depths.
This enhancement could entail removing 28,000 cubic yards of sediment from two areas for
disposal in a large proposed "navigational" CDF. The benefits of this action would be the
possibility of using navigational sediments as preliminary cap material, the removal of additional
PCBs and heavy metals in the navigational sediments, and streamlined permitting procedures. The
navigational dredging would also work in concert with the City's plans for developing the public
and economic uses of the harbor. If the proposed enhancement is accepted, its implementation
would be contingent on appropriate state funding and would be directed by the Commonwealth
and the Army Corps of Engineers, rather than the federal Superfund program. For more
information on the New Bedford Harbor Superfund Site, contact David Dickerson of EPA Region
1 at 617-573-5735.
Region 5
Agency Reviews Public Response to Planned Grand Calumet River
Cleanup
EPA Region 5 is considering responses to comments from the public concerning a USX
Corporation proposal to dredge a portion of the Grand Calumet River and dispose of
PCB-contaminated sediments in a disposal facility to be constructed on USX property in Gary,
Indiana.
USX proposes to remove about 687,000 cubic yards of contaminated sediment from the
upper 5 miles of the East Branch of the river, adjacent to the USX steel production facility known
as the Gary Works. Some 125,000 cubic yards of sediment are contaminated with polychlorinated
biphenyls (PCBs). A USX sediment study completed in 1993 shows that the river contains the
heavy metals iron, lead, zinc, cadmium, and chromium; oil and greases; PCBs; polycyclic
aromated hydrocarbons ; benzene; cyanide; and other pollutants.
The project was proposed by USX in cooperation with EPA and the Indiana Department of
Environmental Management. It will be implemented according to all applicable state and federal
environmental laws. USX has submitted a plan to EPA, which is reviewing it to ensure that the
plan adheres to those laws. The Agency has asked the public to comment on the disposal facility
and on the manner in which some of the sediments will be managed.
Sediment Dredging Proposed
Under a Resource Conservation and Recovery Act (RCRA) corrective action order,
sediments will be dredged using a hydraulic suction pump. Such pumps minimize resuspension of
disturbed sediments, but moving any contaminated sediments has the potential to resuspend
contaminated material in the water column. Consequently, short-term exposure of aquatic life to
contaminated sediments may increase, and contaminated material may be transported to cleaner
areas. USX proposes to minimize these impacts through sound management practices, including
total containment of the most contaminated areas during dredging.
Dredged sediments are to be disposed of in a 40-acre, double-lined corrective action
management unit (CAMU) to be built on USX property. This is the safest way of handling
sediments because they will be taken out of the river completely. The CAMU will be constructed
to contain all dredged sediments and prevent future releases of hazardous constituents. It will be
sited near the project area to minimize sediment transport, in an area formerly used to dispose of
dredged sediments.
After all dredged sediments are placed in the CAMU, the CAMU will be dewatered and the
dredged solids will be consolidated. Wastewater from this process will be collected and treated in
a project-specific treatment system. The oil skimmed from the CAMU will be treated and
disposed of in accordance with applicable state and federal law. Although not a complete
treatment process, this step will reduce some of the sediment toxicity. Once the dewatering has
been completed, USX will install a temporary vegetative cover over the CAMU to control dust
and minimize erosion.
Excess Disposal Capacity
The CAMU will be designed with excess capacity that may be used to dispose of additional
wastes from the site cleanup. By law, only wastes generated during the implementation of the
corrective action may be disposed of in the CAMU. It will not be used for waste disposal from
other site cleanups. The excess capacity would be used only if EPA approves, and if the physical
and chemical makeup of the additional waste is compatible with the dredged sediments.
USX must prepare a groundwater monitoring plan, to ensure that contaminants are contained
by the CAMU, which must be approved by EPA. After the activities specified in the consent order
are completed, USX must submit a closure plan, which also must be approved by EPA. After
closure, USX will routinely inspect the CAMU. The dredging will be an interim measure under a
corrective action order pursuant to RCRA section 3008(h).
The cleanup is expected to take about 5 years to complete. This period includes 2 years for
engineering studies, design, and permit application preparation; 1 year for constructing the
CAMU and wastewater treatment system; and 2 years to dredge the sediments and place them in
the CAMU.
The USX proposal goes beyond the requirements of the settlement of a 1990 federal lawsuit
brought under the Clean Water Act. Under the consent decree that resulted from the suit, the
company agreed to improve its wastewater treatment equipment and its water delivery and sewer
systems; spend up to $2.5 million to investigate pollution in a 13-mile stretch of the Grand
Calumet River and up to $5 million to clean the upper 5 miles of river adjacent to its property;
and pay a $1.6 million fine. For more information, contact Matthew Ohl, EPA Region 5, at
312-886-4442, or ohl.matthew @epamail.epa.gov.
Region 9
Pilot Phase Continues for San Francisco Bay's Dredged Material
Management Office (DMMO)
The 1-year pilot of the interagency office for coordinated decision-making on dredging
permits was established by a Memorandum of Understanding (MOU) signed in early July 1996.
Signatories to the MOU were the Army Corps of Engineers San Francisco District, EPA, the
San Francisco Bay Conservation and Development Commission, and the California State Lands
Commission.
The Dredged Material Management Office (DMMO) is modeled after the interagency Puget
Sound Dredged Disposal Analysis (PSDDA) program in EPA Region 10, providing a cooperative
permitting framework that reduces both redundancy and delays in the processing of permit
applications.
The first of two 6-month pilot phases of San Francisco Bay's DMMO was recently completed.
DMMO staff have prepared a review report discussing the DMMO's accomplishments, issues that
arose during the first 6-month pilot, and staff recommendations for changes to the process to be
implemented during the second 6-month phase.
The DMMO has reviewed information from approximately 60 applications for dredging more
than 4.3 million cubic yards of material in the last year and a half. A noteworthy finding of the
report is that only 3 percent of the dredged material failed standardized testing for open-water
disposal. It had been widely assumed that up to 20 percent of San Francisco Bay dredged material
would fail such testing.
Applicants using the DMMO fill out a consolidated permit application form for dredging and
disposal/reuse of dredged materials that has been developed by the DMMO. The single
application has made the permit process more predictable for all applicants by aligning the
individual agencies' "clocks" for permit processing.
Although some operational and procedural problems were noted during the first phase, there
was consensus on the part of the agency staff that the DMMO has improved interagency
coordination, thereby increasing the efficiency with which dredging permits are being processed.
The second 6-month pilot phase commenced in April. At the end of that phase, the
participants will initiate the policy and statutory changes necessary to permanently implement the DMMO.
For more information, or a copy of the 6-month review report, contact Erika Hoffman, EPA
Region 9, 415-744-1986, or hoffman.erika@epamail.epa.gov.
Round Robin Testing of Chronic Sediment Toxicity Test Methods
Spring 1997 marked the initiation of round robin testing for both the freshwater and
marine/estuarine chronic sediment toxicity test methods. Dr. G. Allen Burton, Jr. of Wright State
University in Dayton, OH is coordinating the interlaboratory comparison for the freshwater
chronic sediment toxicity test methods. These methods include the 42-day chronic sediment
toxicity test for the freshwater amphipod Hyalella azteca and the chronic sediment
toxicity test for the midge Chironomus tentans with a duration of 40 to 50 days.
At least eight laboratories will test both species using two toxic test sediments and one natural
reference sediment. Participating laboratories will also have the option of running the tests with
two artificial sediments consisting of an alpha-cellulose formula and a peat moss formula.
Testing began in March and ended in May 1997. EPA s Office of Science and Technology
and Great Lakes National Program Office, and the National Council of Air and Stream
Improvement, are sponsoring this work. A protocol document will be developed after the tests are
completed.
Dr. Theodore DeWitt of the Battelle Marine Sciences Laboratory in Sequim, WA is leading
the interlaboratory study for the marine/estuarine chronic sediment toxicity test method. This
method consists of a 28-day test for the estuarine amphipod Leptocheirus plumulosus to
measure survival, growth, and reproduction.
Ten laboratories are participating in the round robin testing. The test sediments will consist of
dilutions of sediments from Black Rock Harbor, CT along with a control sediment and a
fine-grained reference sediment.
Laboratories initiated the testing in May and will complete it in June 1997. EPA s Office of
Science and Technology is sponsoring the interlaboratory study. The U.S. Army Corps of
Engineers Waterways Experiment Station in Vicksburg, MS participated in developing the
chronic method and planning the experimental design, and is participating in the round robin
testing.
A protocol document will be developed after testing is completed. For more information,
contact Leanne Stahl of EPA-OST at 202-260-7055.
ORD ACTIVITIES
Research on Solid-Phase TIE Methods for Metals at ORD-Duluth
Where sediments show toxicity to benthic organisms, it is often desirable to identify the
chemicals responsible.
Although toxicity identification evaluation (TIE) methods for water samples (including pore
water) have become routine, methods applicable to solid-phase sediment tests have proven more
difficult. Ongoing research at ORD-Duluth is showing some promise of effective methods for
implicating cationic metals (e.g., copper, cadmium) as sediment toxicants. Two methods have
shown success in certain sediments: 1) supplementing acid-volative sulfide in the sediment and 2)
addition of zero valent metals to induce redox reactions.
Complementary research at ORD-Narragansett has shown that the zero valent metal
technique may be even more effective in marine sediments than in freshwater sediments. It is
hoped that these methods can be refined sufficiently to be included in sediment TIE guidance to
be developed by EPA in the near future. For more information, contact Dave Mount of ORD s
Mid Continent Ecology Division, 218-720-5616; or at epadrm@ du4500.dul.epa.gov.
Changes in Metal Toxicity with pH for Marine Organisms
Metal toxicity is often dependent upon pH. In marine waters, where pH is generally well
buffered (remaining in the range of 8 to 8.3), changing metal toxicity with pH is not well
documented. However, in situ marine interstitial water pH can fluctuate between 6.5
and 8.5, and sediment sampling and consequent mixing may increase interstitial water pH due to
sample oxidation. This pH change is important when assessing the bioavailability of metals to
benthic organisms, particularly in laboratory toxicity testing of sediment porewaters and its
extrapolation to field assessments.
Research at ORD-Narragansett is being conducted to provide information on pH-dependent
toxicity of three common marine test species Mysidopsis bahia (mysids), Ampelisca
abdita (amphipod) and Vibrio fischerii (Microtox solid phase test (MSP))
associated with five common environmental metals (copper, cadmium, lead, nickel, and zinc) at
three pH levels.
Changes in toxicity with respect to pH were generally metal- and organism-specific. For the
MSP assay, with decreasing pH, there was a decrease in lead, nickel, cadmium, and zinc toxicity,
and an increase in copper toxicity. For mysids, as pH decreased lead toxicity decreased, while
copper and nickel toxicity increased. For amphipods, copper toxicity decreased with decreasing
pH, and all other metal toxicities remained constant. Copper toxicity appeared to be the most
dependent on pH.
Metal toxicity for M. bahia, A. abdita, and V. fischerii is largely dependent upon pH, with
both metal- and organism-specific changes in toxicity. These toxicity changes with pH should be
factored into laboratory assessments of field metal toxicity. In addition, they may be useful in
identifying toxic metals during toxicity identification and evaluation procedures.
For more information, contact Kay Ho of ORD at 401-782-3196 or at ho.kay@epamail.epa.gov.
Southeast Chapter of SETAC Holds Annual Spring Symposium
The Southeast Chapter of the Society of Environmental Toxicology and Chemistry (SETAC)
held its 1997 Annual Spring Symposium in Pensacola Beach, Florida on May 8 to 10. The
Southeast Chapter provides a forum for scientists in Georgia, Florida, Alabama, Mississippi, and
Louisiana to exchange information, on issues related to environmental chemistry, toxicology,
ecological risk assessment, and hazard assessment in the Southeastern United States.
For the first time, two short courses were offered in conjunction with the symposium. The
first course, "Identification, Reduction, and Interpretation of Confounding Factors Related to
Marine Ecotoxicological Testing" introduced confounding factors in marine testing related to
sampling, laboratory testing, and data interpretation; presents existing and emerging methods that
account for these factors; and discusses interpretation and application of test results for different
assessment scenarios.
The second course, "Gamete and Embryo Collection Workshop," provided hands-on
instruction on collecting, holding, maintaining embryos for experimental use from freshwater,
estuarine and marine species.
For more information on the SETAC meeting, contact Doug Johnson of Region 4, at
404-562-9386, or by e-mail at johnson.doug@epamail.epa.gov.
ACTIVITIES TIMELINE
July 28 - August 1, 1997
U.S. EPA Water Quality Standards Academy
Washington, DC
For more information or registration, contact:
Kate Belmont
The Cadmus Group, Inc.
Phone: 703-931-8700
Fax: 703-931-8701
August 25-28, 1997
U.S. EPA Multi-Regional Meeting on Water Quality Standards, Water Quality Criteria, and
Water Quality-Based Permitting
St. Louis, Missouri
"Development and Implementation of Tools for Water Quality-Based Pollution Control." Will
provide an exchange of scientific, technical, and policy information on water standards, water
quality criteria, and water quality-based permitting. Pre-registration is required.
For more information or registration, contact:
Liz Hiett
Tetra Tech, Inc.
Phone: 703-385-6000
September 7-11, 1997
Symposium on the Mechanisms and Effects of Resistant Sorption Processes of Organic
Compounds in Natural Particles
Environmental Chemistry Division, American Chemical Society National Meeting
Las Vegas, Nevada
Symposium will deal with slow kinetic phenomena of contaminant soils, sediments, and
aerosols. Topics of interest include transport modeling, particle characterization, fundamental
molecular interactions with natural and model particles, bioavailability, and remediation.
For more information, contact:
Joe Pignatello
Connecticut Agricultural Experiment Station
New Haven, Connecticut 06504
Phone: 203-789-7237
October 12-16, 1997
Estuarine Research Foundation 14th International Conference
Providence, Rhode Island
"The State of Our Estuaries" will be addressed through thematic sessions, oral and poster
presentations, and workshops. Workshop topics include coastal land loss in the United States;
denitrification; ecological economics of estuaries; using the Internet to conduct investigations in
marine science; using stable isotopes to trace linkages between watersheds and estuaries;
investigation-based teaching in introductory coastal and marine courses; regional assessments of
estuarine health; and how scientists can influence elected officials.
For more information, contact:
Estuarine Research Federation
Port Republic, Maryland 20676
Phone: 410-586-0997
Fax: 410-586-9226
e-mail: jbarth@cbl.cees.edu
Conference Proceedings are Being Prepared
The proceedings of the National Sediment Bioaccumulation Conference are in preparation.
They are expected to be available in September 1997.
More than 400 persons attended the conference, which was held on September 11-13, 1996 in
Bethesda, Maryland. The conference was sponsored by the EPA Office of Science and
Technology and the EPA Office of Research and Development.
The event, which featured presentations by national experts in seven sessions, was the cover
story in the Winter 1997 issue of Contaminated Sediments News.
For more information, contact Leanne Stahl, EPA Office of Science and Technology, at
202-260-7055.
First American Wetlands Conference Held in Virginia
Communities Working for Wetlands, a conference held in Alexandria, VA, on May 7-9 1997,
kicked off American Wetlands Month 97 the annual nationwide celebration of wetlands.
The meeting consisted of six concurrent tracks that focused on Wetlands Policy, Working
with and Building Broad Coalitions, Education and Outreach, Tools, Science for the Citizen, and
International Projects. Presenters described wetlands work, emphasizing stewardship and public
involvement.
Other highlights of the meeting included field trips to nearby wetlands; two half-day Wetlands
Primer Workshops; and posters and exhibits.
For further information, contact Stacey Satagaj of The Terrene Institute, at 703-548-5473 or
at terrinst@aol.com.
New Video and Handbook Available
Eroding soils from stream banks add sediment loads to aquatic ecosystems. Two new
products that cover stream bank erosion and wetlands conservation are available from the Izaak
Walton League of America. "Restoring America s Streams" is a 28-minute instructional video on
stabilizing eroding stream banks and restoring degraded stream-side forests using bioengineering
techniques that rely on woody vegetation and special planting patterns.
"Save Our Streams Handbook for Wetlands Conservation and Sustainability,"is a 235-page
handbook to help people become wetland stewards. It details features unique to wetland
ecosystems and explains why wetlands are important.
To order the video ($20), or the handbook ($18), contact the Izaak Walton League of
America, 707 Conservation Lane, Gaithersburg, MD 20878-2983 or call 1-800-BUG-IWLA.
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