Managing Contaminated Sediments:
EPA Decision-Making Processes
Prepared by
U.S. Environmental Protection Agency
Sediment Oversight Technical Committee
EPA Task Manager:
Mike Kravitz
Office of Water Regulations and Standards
Washington, DC 20460
December 1990
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Acknowledgments
This document was prepared by the U.S. Environmental Protection Agency's Sediment Oversight
Technical Committee. The Sediment Oversight Technical Committee, chaired by Dr. Elizabeth
Southerland of the Office of Water Regulations and Standards, has representation from a number of
Program Offices in Headquarters and the Regions.
The present report required hard work on the part of many individuals through a number of drafts.
Critical reviews of the text were provided by the following persons:
Gary Ankley, ERL/ORD Duluth, MN1
Tom Bailey, OPP
Beverly Baker, Region 1
Carol Bass, OERR
Richard Batiuk, Chesapeake Bay Program
Michael Borst, ORD Edison, NJ
Barry Burgan, OMEP
Dave,Cowgill, GLNPO
Becky Cuthbertson, OSW
Cynthia Fuller, GLNPO
John Goodin, OWP
Rich Griffiths, ORD Edison, NJ
Geoff Grubbs, OWRS
Ray Hall, OMEP
Dave Hansen, ERL/ORD Narragansett, RI
Jeffrey Kellam, Region 4
Thomas Kenney, Region 5
Lynn Kolze, OWRS
Catherine Krueger, Region 10
Assistance in preparation and production of this document was provided under EP A Contract Nos
68-C8-0066 and 68-C9-0013.
Elizabeth Leovey, OPP
John Malek, Region 10
Menchu Martinez, OWP
Bill McGovern, OFA
Brian Melzian, Region 9/ERL Narragansett, RI
OssiMeyn, OTS
William Rabert, OTS.
Dave Redford, OMEP
Jerry Smrchek, OTS
Larry Starfield, OGC
Nelson Thomas, ERL/ORD Duluth, MN
Dennis Tirnberlake, ORD Cincinnati, OH
Tom Wall, OWRS
Richard Witt, OGC
Rob Wood, OWEP
Howard Zar, Region 5
Larry Zaragoza, OERR
Chris Zarba, OWRS
EPA office acronyms are defined in the glossary.
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Table of Contents
Acknowledgments \. iii
List of Figures ....' v{j
List of Tables vii
Executive Summary be
Glossary '. . '... xjij
Chapter 1: Introduction ;... i
Contaminated Sediments Issues Framework -.-.. 3
Finding Contaminated Sediments ." ........;..... '.....- 3
Assessment of Contamination ^ 5
Prevention and Source Controls '. .6
Remediation . ; ; . ... 9
Treatment Options .........!........... 13
Disposal Options '....:'..' 15
Chapter 2: Existing Decision-Making Procedures 17
Finding Contaminated Sediments / 17
Assessment Options 19
Prevention and Source Controls : 34
National or Regional Scale U
Local or Site-Specific Scale ..... .... .... ..... 3"
Remediation Options 39
No Action .'. ;..-. 3Q.
Treatment In-Place ... 40
Sediment Removal ., 40
Treatment of Removed Sediments ;.. 41
Disposal of Removed Sediments .41
Chapter 3: Comparison of Existing Decision-Making Procedures for Contaminated Sediment
Management ........>...,. .:. ...'.47
Finding Contaminated Sediments 47
Assessment of Contamination . 49
Prevention and Source Controls ,. 51
Remediation ...-. 52
Treatment of Removed Sediments .' 53
Disposal of Removed Sediments . .: 53
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Chapter 4: Future Directions: The EPA Sediment Strategy ,..., ;' .55
The Sediment Strategy 55
Major Issues 55
Cross-Program Issues > . 55
Potential Impact of the Management Strategy'. 58
Finding Contaminated Sediments „. 53
Assessment of Contaminated Sediments 1 „ 53
Prevention and Source Controls .... : .. 58
Remediation ;....• 59
Treatment of Removed Sediments ,i 59
Disposal of Removed Sediments :..'.« ! 59
References v 61
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VI
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'List of Figures
Figure 1. Contaminated Sediments Issues Framework .. 4
• Figure 2. Remedial Action Alternatives and Considerations 10
Figure 3. General Risk Assessment Framework Under Superfund , 21
Figure 4. Dredged Material Testing Framework Under MPRSA 23
Figure 5. EPA Region V Testing Strategy for Navigational Dredging Projects ... *. . 29
Figure 6. Dredged Material Testing Sequence Under PSDDA -.... „ , 31
Figure 7. IJC Sediment Subcommittee Sediment Assessment Strategy .. ';...• 33
Figure 8. COE Dredged Material Management Strategy :... 44
Figure 9. IJC Dredging Subcommittee Dredging Project Evaluation Framework 45
List of Tables
Table 1. Finding Contaminated Sediments -.,.-..' 48
Table 2. Assessment of Contamination ... 50
Table 3. Prevention and Source Controls .., 51
Table4. Remediation ......... . .\. 52
Table 5. Disposal of Removed Sediments .......' 54
VII
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Executive Summary
The purpose of this document is to summarize how the Environmental Protection Agency (EPA)
makes decisions with regard to managing contaminated sediments. Traditionally, contaminated
sediments have been most closely regulated by the Office of Marine and Estuarine Protection (OMEP)
under the Marine Protection, Research, and Sanctuaries Act (MPRSA) for ocean dumping and the
Office of Wetlands Protection (OWP) for dredge and fill activities under the Clean Water Act (CWA)
In recent years, however, it has become increasingly apparent that the scope of the contaminated
sediments problem extends far beyond this traditional context. A comprehensive management program
is needed in order to address the range of contaminated sediment issues.
For the purposes of this document, management activities relating to contaminated sediments are
divided into the following six categories of activities:
• Finding contaminated sediments — Identification and monitoring.
• Assessment of contaminated sediments — Determining the effects of sediment contamination
on the environment.
• Prevention and source controls — Reducing and preventing sediment contamination through
permitting and enforcement activities.
• Remediation — Determining when, how, and to what degree contaminated sediments should be
remediated. '
• Treatment of removed sediments — Determining when and how removed sediments need to be
treated before disposal. .
• Disposal of removed sediments — Selecting appropriate disposal methods for removed co-n- /
laminated sediments. -..--.'.
The level of development of regulatory authority and programmatic guidance under each of these
categories is uneven. Because of the past emphasis on dredge and fill activities, the amount of
programmatic guidance in this area is great, especially for ocean waters. On the other hand, guidance
on monitoring, assessment, prevention and source controls, and treatment is not as well developed. The
general status of activities under each of the six categories is as follows:
• Finding contaminated sediments — CWA activities are focused on effluent monitoring and
water quality assessment. No national guidance on sediment monitoring is available. Some States
have adopted regular sediment monitoring programs, but in most States it is done only as part of
special studies. Monitoring activities are undertaken under the Comprehensive Environmental
Response, Compensation and Liability Act (CERCLA) and Resource Conservation and
Recovery Act (RCRA) programs. However, these activities are usually focused on the immediate
vicinity of specific sites. Under CERCLA. States and Regions identify sites where contamination
is suspected and sites are assessed to determine whether there is a hazard. Under RCRA, facilities
are required to identify past releases of contaminants and may be required to search for past and
present contaminant releases. CWA and MPRSA require dredged material disposal site monitor-
ing, but, again, data is specific to sites. The Great Lakes National Program Office (GLNPO) has
conducted site monitoring as part of special st udies and Region X conducts monitoring as part
• LX
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of its Puget Sound activities.-Monitoring is needed to determine existing background levels of
sediment contamination, to be able to measure trends in sediment quality and to determine when
more comprehensive studies or remedial actions are needed.
• Assessment of contaminated sediments — National sediment quality criteria are not,yet
developed Several States are in the process of developing and implementing sediment criteria.
Superfund performs assessments based upon site-specific "applicable or relevant and appropriate
requirements" (ARARs) rather than on general guidelines for handling sediments. Various
approaches to assessment are being used in the different programs and Regions, including
equilibrium partitioning-based criteria, bioassays, Apparent Effects Thresholds (AET) and ref-
erence approaches. The "Green Book," developed under MPRSA §103, provides an assessment
tool for dredged material disposal in ocean waters which could have broader applicability.
National testing guidance under CWA §404 similar to the Green Book is being developed. Some
Regions have developed their own assessment protocols which use various approaches, par-
ticularly in implementing CWA §404 and MPRSA §103 programs. In general, consistent criteria
and assessment protocols are needed.
• Prevention and source controls — To date, sediment contamination considerations have not
been used in establishing permit limits for point sources under the CWA Limits for pesticides
have been based on benthic organism effects and controlled under the Federal Insecticide.
Fungicide and Rodenticide Act (FIFRA). Toxic Substances Control Act (TSCA) limitations can
also be placed on chemicals. Enforcement actions have been taken against several dischargers
who were obvious sources of sediment contamination. There is presently no guidance on when
and how to undertake sediment-related enforcement activities.
• Remediation—There is presently no national guidance specific to sediments on when remedia-
tion should take place or on the selection of possible cleanup options. Guidance on remediating
Superfund sites is provided under CERCLA, but it does not explicitly target sediments. Remedia~
tion options involving the removal of sediments may use the guidance developed for dredge .md
fill activities by EPA, the Corps of Engineers and some States. Some remedial efforts are "i.ikinc
place as a result of regulatory actions under CERCLA and CWA.
• Treatment of removed sediments — There is no clear guidance on the selection of treatment
options or determining when treatment should take place. Current decisiom-making is on j
case-by-case basis. Several Programs are studying the efficacy of various treatment options on j
demonstration scale. It is expected that guidance on the suitability and selection of treatment
options will result from this work.
• Disposal of removed sediments—A complete set of tiered testing protocols has; been estahl i>N.-d
for assessing materials for ocean disposal under MPRSA §103 on the national level. Sever ii
Regions have issued guidelines for the specific procedures within the protocols. As stated aK »\ e
similar CWA §404 guidance is under development. OMEP and OWP in conjunction with CUE
have developed a dredged material disposal strategy which is currently in draft form. The st ru te g>
aims at choosing environmentally appropriate disposal options, taking into account physical.
chemical, and biological impacts. •
An EPA Sediment Steering Committee is currently preparing an Agency-wide sediment manage
ment strategy to coordinate and focus the Agency's resources on contaminated sediment problems. The
sediment strategy gives special attention to cross-program issues such as establishing a natmn.il
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inventory ot contaminated sites and sources, establishing consistent testing protocols for assessments.
and utilizing/establishing enforcement authorities for sediment remediation. The strategy will also,
address other sediment issues relevant to EPA, programs. EPA plans to have a draft sediment
management strategy ready for publication in the Federal Register by the end of 1991.
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XI
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Glossary
AET Apparent Effects Threshold approach
AOC Area of Concern (as defined by the IJC for the Great Lakes Basin)
ARARs Applicable or Relevant and Appropriate Requirements
ARCS Assessment and Remediation of Contaminated Sediments program under GLNPO
BAT Best Available Technology
CAA Clean Air Act
s • -
CAD Confined Aquatic Disposal
CDF Confined Disposal Facility
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CFR Code of Federal Regulations
COE U.S. Army Corps of Engineers -
CWA Clean Water Act
DMASS Dredged Material Alternative Selection Strategy
EEB EPA Ecological Effects Branch
EIS Environmental Impact Statement
• » " . . ' W '"
EPA U.S. Environmental Protection Agency
EP Extraction Procedure (a chemical extraction defined in 40 CFR Parts 261,10 2b 1 ? *•>
EqP Equilibrium Partitioning approach
ERL EPA Environmental Research Laboratory
FIFRA Federal Insecticide, Fungicide, and Rodenticide Act
GLNPO EPA Great Lakes National Program Office
GLWQA Great Lakes Water Quality Agreement (between the U.S. and Canada)
HRS Hazard Ranking System (under Superfund)
IJC International Joint Commission (overseeing implementation of the GLWQA)
LCso Concentration Lethal to 50 percent of the exposed organisms
LDC London Dumping Convention
ML Maximum Level of chemical concentration (used in PSDDA sediment testing framework)
MPRSA Marine Protection, Research, and Sanctuaries Act
NAAQS National Ambient Air Quality Standards
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NMFS National Marine Fisheries Service ;
NOEL No Observed Effects Level
NPDES National Pollutant Discharge Elimination System •;
NPL National Priorities List - i
NSPS New Source Performance Standards ! •
OERR EPA Office of Emergency and Remedial Response (for Superfund activities)
OMB EPA Office of Management and Budget
OMEP EPA Office of Marine and Estuarine Protection
OPP EPA Office of Pesticide Programs
ORD EPA Office of Research and Development
OSW EPA Office of Solid Waste
OTS EPA Office of Toxic Substances !
OW EPA Office of Water ' !
OWP EPA Office of Wetlands Protection • j
I . '
OWRS EPA Office of Water Regulations and Standards f
PCBs Polychlorinated Biphenyls
PSDDA Puget Sound Dredged, Disposal Analysis
PSEP Puget Sound Estuary Program
RCRA Resource Conservation and Recovery Act
RI/FS Remedial Investigation/Feasibility Study (part of Superfund site assessment process)
ROD Record of Decision (part of Superfund site remediation process) :
SITE Superfund Innovative Technology Evaluation j
SL Screening Level of chemical concentration (used in PSDDA sediment testing framework)
TBP Theoretical Bioaccumulation Potential
TBT Tributyltin
TCLP Toxicity Characteristic Leaching Procedure
TEA Triethylamine . ''
TMDL Total Maxinium Daily Load
TSCA Toxic Substances Control Act \
USFWS U.S. Fish and Wildlife Service !
WLA Wasteload Allocation
It K
XIV
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Chapter 1
Introduction
Issues related to the contamination of bottom sediments with toxic chemicals and the potential for
environmental damage are receiving increased attention by the public and State and Federal
Agencies. Managing contaminated sediments requires that decisions be made on assessment of environ-
mental harm, prevention and source controls, dredged material management, and remediation.
The purpose of this document is to identify the U.S. Environmental Protection Agency's (EPA)
current decision-making process (across relevant statutes and programs) for assessing and managing
contaminated sediments. It is intended to provide decision-makers throughout the Agency with
information that will aid them in making effective judgements regarding national or regional approaches
for dealing with contaminate^ sediments. The document partially fulfills one of the goals of the
Agency-wide sediment management strategy (discussed in Chapter 4) which calls for gathering infor-
mation on EPA decision-making processes and explaining differences among Program Offices. Use of
this information will allow EPA to prepare a strategy that adequately addresses gaps, in current
decision-making on sediments.
The discussion in this document is intended to highlight the way in which decisions are currently
being made rather than on how they may be made in the future when protocols that are currently under
development are adopted. However, important decision protocols that are being developed or that have
been developed but are not in use are also discussed.
In order to help identify relevant contaminated sediment management issues and to provide a
background for subsequent discussions on how they are being addressed by existing programs, a general
contaminated sediments issues framework is presented in this chapter. It is important to emphasize that,
this framework is only presented to provide structure for the discussions of existing programs; it is not
EPA's contaminated sediment management policy or protocol. However, the identification, in this
document, of how well existing programs address contaminated sediment issues is an important step
toward the development of such policies and protocols.
Management activities relating to contaminated sediments can be separated into the following six
categories:
• Finding contaminated sediments — Identification and monitoring.
• Assessment of contaminated sediments — Determining the effects of sediment contamination
on the environment
• Prevention and source controls — Reducing and preventing sediment contamination through
permitting and enforcement activities.
• Remediation — Determining when, how, and to what degree contaminated sediments should be
u remediated, and regulatory or other measures which result in EPA, responsible parties, or others
performing a remedial project
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2 Chanter I
• Treatment of removed sediments — Determining when and how removed sediments need to be
treated before disposal, and the implementation of such treatment.
• Disposal of removed sediments — Selecting appropriate disposal methods and locations for
removed contaminated sediments, and the implementation of disposal projects!.
Until recently, the EPA has not generally emphasized the quality of sediments except in relation
to the disposal of dredged material removed during navigational dredging. The U.S. Army Corps of
Engineers (COE), the Federal agency responsible for maintaining waterways for navigational purposes,
and the EPA have developed protocols for evaluating dredged materials and disposal options. These
protocols, which are currently being revised for ocean water disposal under §103 of the Marine
Protection, Research and Sanctuaries Act (MPRSA) and are being adapted for freshwater and
estuarine disposal under §404 of the Clean Water Act (CWA), essentially focus on the suitability of
dredged materials for disposal in the aquatic environment. Other statutes control the disposal, of
dredged material on land.
Sediment monitoring and assessment activities are generally performed under the CWA, the
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), the Resource
Conservation and Recovery Act (RCRA) and MPRSA. Sediment contamination prevention and source
control actions can be taken under a variety of authorities depending on the particular circumstances.
Such authorities include the CWA, the Toxic Substances Control Act (TSCA), the Resource Conser-
vation and Recovery Act (RCRA), the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA),
and the Clean Air Act (CAA). While there may be broad authority under CERCLA and some authority
under the CWA and RCRA to remove contaminated sediments from water bodies, not many actions
have been taken thus far to remediate sediments.
Sediment quality criteria are under development and have been published in preliminary form for
some toxic organic chemicals (USEPA, 1988a). EPA is considering approaches to the use of these
criteria in managing sediment quality (USEPA, 1989a). Such criteria may be useful in sediment
assessment, to aid in determining the need for source controls, and in sediment remediation, treatment
and disposal.
This document is organized as follows:
• Chapter 1 presents a contaminated sediments issues framework. The framework is used to
introduce relevant contaminated sediment management issues.
• Existing decision-making programs and procedures for sediment monitoring and assessment,
contamination prevention, remediation and disposal of contaminated sediments are summarized
in Chapter 2. The contaminated sediments issues framework is used to structure the discussions.
• Chapter 3 identifies gaps between existing programs and the relevant issues identified in the
contaminated sediments issues framework. In addition, inconsistencies and overlaps between the
various existing programs are identified. . . •
• Chapter 4 presents an overview of the sediment management strategy which-is being developed
under EPA's Sediment Steering Committee.
The information presented in this document is subject to modification in accordance with changes
in program and/or regional approaches to managing contaminated sediments.
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Introduction 3
Contaminated Sediments Issues Framework
Contaminated sediments can pose serious threats to human health and the environment by serving
as a persistent source of toxic chemicals to humans or aquatic organisms. Human exposure results from
direct contact, eating fish and shellfish that have accumulated toxic materials, and drinking water which
has been exposed to contaminated sediments. Aquatic organisms, particularly benthic species, are
continuously exposed to the contaminants in sediments, which may result in adverse biotic effects
including chronic and acute toxicity. The accumulation of toxic chemicals within aquatic organisms may
be sufficient to preclude, their use for human consumption and possibly pose a threat to wildlife. If the
environment is to be preserved for future generations, the contaminants in sediments must be treated
and/or contained in ways that eliminate current and potential exposures to humans and aquatic
organisms. Further degradation of sediment quality must also be prevented.
There are several options for isolating the contaminants in sediments. They range from allowing
natural sedimentation to bury the contaminants to removing and treating sediment and isolating it from
the rest of the environment. In those cases where contaminated sediments occur in areas that must be
dredged to maintain navigation, sediment removal is essentially the only option, but disposal then
becomes problematical.
Figure 1 outlines the major options for control of sediment contamination. There are two major
entry points to the selection of options: 1) when contaminated sediments are suspected, and 2) when
dredging must occur for navigational reasons. In general, the decision process for sediments which are
slated for dredging can skip those options that don't involve removal of the sediments. There are cases,
however, where COE will avoid dredging if it is too costly relative to benefits.
At each decision point, there are generally one or more options for taking action, and a no action
alternative. Thus, if contaminated sediments are encountered, the only action that may be required to
be taken is the reduction of contaminant sources. However, other options can be exercised if they are
necessary to obtain acceptable sediment quality. Similarly, if dredged material is removed for naviga-
tional reasons, the only actions required are treatment (if necessary) and disposal.
The remainder of this chapter discusses the important issues that arise in the process of selecting
contaminated sediments management options.
Finding Contaminated Sediments
Before full-scale, potentially costly sediment assessment programs are begun, the initial identifica-
tion of areas containing probable contamination problems should be attempted. The contamination of
sediments is a process influenced by a number of variables including contaminant source* contaminant
type, sedimentary and hydrologic environment, sediment grain size distribution and composition.
presence and type of aquatic life, and historical influences.The likelihood of there being a sediment
contamination problem at a particular site needs to be appraised based on readily available information.
Such information may be available from ongoing monitoring or regulatory, programs^ previous site
characterizations, dredging records, discharge permits, area maps, fishing advisories, reports of spills.
fish kills and beach closings, etc. It is worth noting that sediment contamination problems need not be
connected to poor water quality. The ability of sediments to retain contaminants over time makes it
possible for sediments to remain contaminated while water column contaminant concentrations remain
below applicable water quality standards.
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Finding Contaminated Sediments
Information torn
Onfloloo monitoring
and rtfiuteory program*
Ffthlnfl (dvliorlti
•Anecdotal «vtd«ic«
Spills, flan kill. •ic.
Contamination Suspected I
Assessment
Hotogteal testing
• Chemical testing. T f
7IT~...
Criteria comparisons
Prevention and
Source Controls
TSCAban
zi-
Aquatic discharge
G
"FIFRAuse
"Reduce "~j I" ' Reduce I f— ~—-~'
pow 8our«,i___ J L ngipolntjiources.. J [ cor^ye action
I Of edging actions |
Remediation
|^j Treat In-place [ No action
IZ7 1
Immobize
contamlnantg
Treatment
Disposal
-. t - -
Contaminant
- 1
Solvent
extraction
|
Contaminant
Immobilization
/
"~~ *. *- — — , [
Be^SdalUse
'• i • • • '
Contned
dJscosaiticaitv
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1 Aquatic I (—
1 dlsoosai ! !
'
_._ 1
Han
lous ]
md§! „_;..]•
f—dp,
I *
..
Open water
dteposal
Conflnad
aquatic disposal
Figure 1. Contaminated Sediments Issues Framework.
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Introduction
Assessment of Contamination
When an initial screening indicates the possible presence of a sediment contamination problem.
more complete characterization of the sediment is needed, including an assessment of the environmen-
tal threat posed by the contamination. In the selection of sediment assessment methods, the first
-consideration fc determining what is to be protected. Assessment methods will vary in their ability to
indicate effects on aquatic life, wildlife, or human health.
The simplest assessment approach is the direct comparison of observed concentrations of sediment
contaminants to some pre-established criteria. Sediment quality criteria are more difficult to develop
thansimilar water quality criteria because of the number and complexityof factors affecting the intensity
of biotic effects created by a given chemical concentration. Sediment quality criteria are currently under
development by EPA. A generic definition of sediment quality criteria is as follows:
A sediment criterion is a specific level of protection from the adverse effects of sediment associated
pollutants, for beneficial uses of the environment, for biota, or for human health. The criteria may
be specified in a number of ways, but most commonly as concentrations of individual pollutants,
as toxic units for whole sediment toxicity, or in terms of pass/fail based on tests of acute or chronic
tcadcity or bioaccumulation.
'- Sediment criteria are intended to accurately reflect the latest scientific knowledge:
• on the kind and extent of all identifiable effects on health and welfare including, but not limited
to, plankton, fish, shellfish, wildlife, plant life, shorelines, beaches, aesthetics and recreation
which may be expected from the presence of pollutants in sediments and grdundwater,
• on the concentration and dispersal of pollutants, or their byproducts, through biological, physical.
and chemical processes, and
• on the effects of pollutants on biological community diversity, productivity and stability m
addition to eutrophication and organic/inorganic sedimentation.
The Office of Water Regulations and Standards is developing sediment quality criteria for a number
of contaminants using water quality criteria and an equilibrium partitioning (EqP) approach (US EPA.
1989b; 1990a). The EqP approach is based on a simple model that describes the partitioning of a
contaminant between sediment phases which bind the contaminant and interstitial water. Interim
criteria have been published for some organic contaminants (USEPA, 1988a). Sediment quality criteria
may also be developed from other approaches, such as the Apparent Effects Threshold (AET) approach
developed by Region X, or the bulk sediment toxicity tests used in the tiered testing strategy ot the
Draft Ecological Evaluation of Proposed -Discharge of Dredged Material into Ocean Waters (USEPA
1990b). A review of the strengths, weaknesses, and applicability of these and other approaches for
assessing sediment quality is provided in the draft document Sediment Classification Methods Compen-
dium (USEPA, 1989c). A brief description of the approaches is found below. They range in complexity
from simple chemical characterizations of the sediments to multi-pronged approaches utilizing chemical
and biological testing along with benthic community structure analysis. Except for the Reference
Approach, the definitions given below are taken directly from the Sediment Classifications Methods
Compendium (USEPA, 1989c). .
• Reference Approach — Sediment contaminant concentrations at a site are compared with
background concentrations from "unaffected" sites from the same area.
• Bulk Sediment Toxicity Test — Test organisms are exposed to field-collected sediments which
may contain unknown quantities of potentially toxic chemicals. At the end of a specified time
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6 Chapter I
period, the response of the test organisms is examined in relation to a specified biological
endpoint. • •
• Spiked-Sediment Toxicity Test — Dose-response relationships are established by exposing test
organisms to sediments that have been spiked with known amounts of chemicals or mixtures of
chemicals. .
• Interstitial Water Toxicity Test — Toxicity of interstitial water is quantified and identification
evaluation procedures are applied to identify and quantify chemical components responsible for
sediment toxicity. The procedures are implemented in three phases to characterize interstitial
water toxicity, identify the suspected toxicant, and confirm toxicant identification.
• Equilibrium Partitioning Approach — A sediment quality value for a given contaminant is
determined by calculating the sediment concentration of the contaminant that would correspond
to an interstitial water concentration equivalent to the U.S. EPA water quality criterion for the
contaminant. i
• Tissue Residue Approach — Safe sediment concentrations of specific chemicals are established
by determining the sediment chemical concentration the will result in acceptable tissue residuei
Methods to determine unacceptable residues are based on chronic water quality criteria and
bioconcentration factors, chronic dose-response experiments or field correlations, and human
health risk levels from the consumption of freshwater fish or seafood. i
• Benthic Community Structure Analysis — Environmental degradation is measured by e%alu*t
ing alterations in benthic community structure.
• Sediment Quality Triad Approach — Sediment chemical contamination, sediment toxjcir\ and
benthic community structure are measured on the same sediment. Correspondence Nr>r«:*
sediment chemistry, toxicity, and biological effects is used to determine sediment concer.: * i - -j
that discriminate conditions of minimal, uncertain, and major biological effects.
• Apparent Effects Threshold (AET) Approach — An AET is the sediment concentration t /
contaminant above which statistically significant biological effects (e.g., amphipod mor:jur\ «
bioassays, depressions in the abundance of benthic infauna) would always be expected M 7
values are empirically derived from paired field data for sediment chemistry and a ran|« . (
biological effects indicators. .
• International Joint Commission (LJC) Sediment Assessment Strategy — Contaminated »cO.
ments are assessed in two stages: 1) an initial assessment that is based on macrozoobemf*
community structure and concentrations of contaminants in sediments and biological tissues
2) a detailed assessment that is based on a phased sampling of the physical, chemical.
• biological aspects of the sediment, including laboratory toxicity bioassays.
Prevention and Source Controls
When sediment contamination is found, it is usually important to determine the cause of the
problem. If, for example, continuing discharges are linked to sediment contamination, controls *ould
be considered. On the other hand, if a spill is the cause, source controls may have little effect on
contamination levels.
The type of action to take is partly dependent upon the scale of contamination. If a sediment
contaminant is elevated at numerous sites nation-wide, it may be relatively inefficient to deal with it
only on a local basis. The sources are probably so numerous that action on individual discharges would
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Introduction
be inefficient. It is best under these circumstances to attempt control on a nation-\vide basis through
regulatory or programmatic means. On the other hand, a single contaminated site may need to be
controlled at the local level, arid national controls are less relevant or useful. The first significant
1 information requirement, then, is to determine the scale over which sediment contamination occurs for
each contaminant If contamination, occurs on a national or'regional level, actions could be taken under
TSCA or FIFRA to restrict the production, distribution, or use of the contaminant. Similarly, if the
major contaminant source appears to be atmospheric, appropriate standards can be developed under
theCAA, •',/•-
Even with appropriate national, regional, or local guidelines for sediment contaminants, individual
sites create special cases. Each site is unique and, therefore, case-by-case handling will,be necessary in
many circumstances. Contamination "hot spots" also deserve special handling. In such cases, it may be
inappropriate to forestall source control actions until programmatic or regulatory action is taken if such
a delay would result in unacceptable environmental impacts.
r It is also worth noting that the presence of a particular sediment contaminant in numerous locations
nationally or regionally does not necessarily indicate the need for national source controls. Sediments
store contaminants and even though discharges of a given contaminant were halted some time ago. the
contaminant may persist in the sediments. Clearly, efforts for this kind of contamination problem need
to be focused on remediation rather than source control.
The best way to directly relate sediment contamination to possible sources is to deal oh a con-
taminant-by-contaminant basis. Toxicity testing does not directly identify the problem contaminants, i:
may play a significant role in the initial screening of potentially contaminated sediments, and — through
the use of techniques such as toxicity identification evaluation procedures — it can identify- the
contaminants most likely responsible for observed toxicity. Geographic relationships between peak
sediment contaminant concentrations and possible sources can also be used to link sediment contamina-
tion to sources.
When multiple sources for a given contaminant exist (e.g., multiple producers of a given con-
taminant in a single harbor), additional evidence can be used to tie a sediment contaminant to its source".
Concentration gradients of the contaminant may be observed across the sediment surface with the
highest contamination levels observed directly below the responsible outfall. Or contaminants may
increase at certain depths in the sediment column indicating the history of the production or use ot a
contaminant by a particular facility. Finally, it may be possible to "fingerprint" a facility by matching the
occurrence or relative concentrations of other contaminants that were emitted concurrently *ith the
contaminant of interest by a particular facility. Identification of sources in this way should be considered
when a sampling and testing program is being developed.
If contamination is restricted to a local area, the first consideration is whether the contamination
source is ongoing of historical If the contamination source is purely historical (e.g., a previous spill.. T
a now obsolete discharger), then source control can be ruled out as a method of contaminant reduc t u -n
It is useful to consider three general categories of sources in this discussion:
• Point sources — Municipal and industrial effluent, combined sewer overflows, •,
• Nonpoint sources —. Agricultural runoff, stormwater runoff, airborne contaminants (atmo-.-
pheric deposition),
• Other sources — Spills, infiltration of contaminated groundwater, downstream transport vt
contaminated sediments, aquatic dumping.
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8 Chapter 1 '-"
Because of the water quality-based effluent limitations possible under the CWA, it is generally
appropriate to focus initial attention on point source discharges. A number of questions need to be *'
answered when considering the need for point source controls: - . \
• Where are point sources located? j
• What are their loadings for the contaminants of concern? j "
• Allowing for historical contamination, are point sources substantially responsible for the level of
contamination found? ,
• What type of discharge is responsible for the contamination (i.e., municipal vs. industrial process
vs. cooling water) ..
• Are required reductions in point source discharges economically and technically feasible relative
to the expected benefits to be obtained?
If point sources are apparently responsible for the contamination, then the sitrategy for sediment
contamination prevention can focus on point sources (e.g., recalculating waste load allocations (WLAs)
to account for storage capacity of sediments and modifying permit limits to reflect the new WLA).
Nonpoint sources are capable of contributing significantly to sediment contamination. They require
examination in the same way as point sources. The information requirements are the same:
• Where are nonpoint sources located? . ,
• What are their loadings for the contaminants of concern? j
• Allowing for historical contamination, would nonpoint sources be substantially responsible for
the level of contamination found?
• What is the pathway for the nonpoint contamination(i.e., airborne vs. agricultural, and urban,
runoff vs. mining seepage, etc.)?
• Are required reductions in nonpoint source discharges economically and technically feasible
relative to the environmental benefits to be obtained?
• Are there point sources remotely associated with the nonpoint contaminants (e.g., an initial
source of airborne contaminants) that also need to be controlled?
Under CWA, control of nonpoint sources can be somewhat problematical. While there are
authorities for the control of point sources in all States, no States have comprehensive regulatory
programs for the control of nonpoint source pollution. Some State and local governments have enacted
ordinances, regulations, or voluntary programs for controlling specific sources of nonpoint pollution.
yet none have developed a comprehensive regulatory program to control all sources.
One way to overcome the possible limitations of nonpoint source controls is to seek other methods
to achieve the same end. RCRA and CERCLA allow the control of environmental releases from
contaminated sites. Corrective action can be taken under the appropriate statute to prevent further
contributions of contaminants to sediments. Questions about the appropriateness of using such
provisions include: ' .
• Are there existing RCRA permitted or interim status facilities or CERCLA sites that are or have
been releasing the contaminants that are elevated in off-site sediments?
• At what levels are these facilities/sites releasing contaminants? ,
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Introduction 9
• Are there identifiable control actions that can be taken to reduce discharges from the sites?
• What are the relative costs of controls to obtain the necessary discharge levels relative to the
expected environmental benefits to be obtained?
Controls for other sources of sediment contamination must be instituted on a case-by-case ..basis
using appropriate elements of both water arid hazardous waste regulatory authorities.
Remediation
Contaminated sediments have not been frequently remediated due to:
•• The lack of a clear regulatory and programmatic avenue to do so;
• The generally high costs of remediation; and
• The lack of established criteria for determining action and. cleanup levels.
The environmental benefits of remediation need to be weighed against the costs of remediation
and its possible environmental impacts. For instance, benthic habitat may be lost due to sediment
removal or by capping. Or the loss of contaminated sediments during dredging may spread contamina-
tion to other areas. Therefore, one needs to be reasonably certain that the positive benefits of a plan
of remediation outweigh the negative impacts before action is taken.
Basically, sediments should be remediated when "acceptable" environmental quality will not be
achieved by natural processes within a "reasonable" period of time. Both adjectives are in quotes
because acceptable and reasonable are not currently defined in practical or operational terms! Theoreti-
cally, sediments that exceed sediment quality criteria and/or demonstrate adverse environmental
impacts are not acceptable, but how long unacceptable sediments should be allowed to exist is
problematical. In any case, the information needed to make a decision on whether or not reme'dut;on
should occur is as follows: ;
• Will contaminated sediment be sufficiently covered over by clean, natural sediments or natura'.!\
degrade within a reasonable time frame?
« Will covered sediments be released by storms or other mechanisms?
• Have sources been controlled sufficiently that significant sediment contamination will not recur
if remediation is undertaken? ..
• Does the contaminated sediment itself pose a danger to larger areas (transport downstream i it
left unremediated?
• Are there technically and economically feasible alternatives for remediation?
. • Are adverse environmental, human health, and beneficial use impairments severe enough to
warrant remediation?
• Will the positive long-term benefits of remediation outweigh the possible negative short-term
impacts of the action?
While it is desirable that sources of continuing contamination be controlled either prior to or
concurrent with remediation efforts, it may be necessary to proceed with remediation ahead of et'fecuv c
source controls if the contaminated sediments pose a sufficiently great environmental hazard. A factor
that must be kept in mind in the decision-making is that contaminated sediments can be transported to
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10 Chapter I
downstream or offshore areas if left in-place, thereby greatly increasing the size of the contaminated
area, thus making future remediation efforts much more difficult. ,
There are three general sediment remediation options (see Figure 2):
/ , • \
• Take no action and let natural sedimentation cover them over, , -
1 .
Remediation Options
No action
•Sources not
yet controlled
i
1 • Natural recovery
; expected in a
. reasonable
: timeframe
•Remedial action
may pose greater
threat than
I no action
f
i
*
i
>
•
i
i
In-place Treatment
#
• Low energy,
non-erosive
environment
•No dredging
or construction
planned
•Sediments not
contaminating
other media
(e.g., ground-
water)
I -.- . , •
Removal
•RemovaJ will cause
minimal adverse \
impact
•Dredging needed
for navigiation
•Viable disposal
options exist
,„,,,„
• i
i .• .
Figure 2. Remedial Action Alternatives and Considerations
• Treat them in-place, or , [
• Remove them to another area with or without treatment. j
For any given site, however, a combination of options may be appropriate. Impending on the
considerations listed below, sediments in one part of a site may be removed, while icreatment in-place
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Introduction 11
or no action may be appropriate for other parts. Which options to choose are site- or locality-specific
and may depend on the resources available and potential disposal.options.
In general, the expected environmental benefits, possible adverse impacts, the time frame for
natural recovery and the feasibility and cost of various treatment and removal options are the major
determinants in selecting options for a particular location. The weight given each of these factors varies
under the regulatory/programmatic framework under which remediation is performed.
.Questions which need to be answered at this level include:
• How long would it take for the sediments to recover naturally to acceptable levels?
• Must the contaminated area be dredged for navigational purposes?
• Will the remedial action option significantly alter the hydrology or habitat of the area?
« Will the remedial action option be sufficiently permanent to warrant the expense (i.e., will a cap
be eroded by currents or waves)? ,
• What are the relative costs of dredging and disposal versus treatment in-place?
• What are the relative environmental risks and benefits of the alternatives?
The no action option is most viable when one of the following situations exists:
• The sources of sediment contamination have not yet been significantly reduced, eliminated or
controlled. Taking remedial action in this case is not effective because the sediments would soon
be re-contaminated. The most prudent action is to control the sources before undertaking any
remedial action on the contaminated sediments. An exception exists where sediments pose a
threat of becoming a source of further contamination of downstream areas or groundwater.
OR
• The sources of sediment contamination have been eliminated or controlled and the contaminated ,
sediments are in a low energy, non-erosive environment which will not be disturbed by dredging
or construction activities or by natural means such as storms. In this case, a natural cap of clean
sediment is being formed over the contaminated sediments, reducing or eliminating the transfer
of pollutants from the sediments to the overlying water and biota.
OR
• The sources of sediment contamination have been eliminated or controlled and remedial action
is desirable. However, taking remedial action would be more environmentally damaging than
leaving the contaminated sediment in-place untreated.
In general, in-place treatment is appropriate when all three of the following conditions apply:
• The sediments are in a low energy, non-erosive environment. After in-place treatment, the
treated sediments will remain undisturbed by natural forces.
\ • ' AND •..'.. - -
• The sediments will not be disturbed by dredging or construction activities. Such activities could
render the in-place treatment ineffective by re-exposing contaminated sediments or by breaching
an established barrier. Alternatively, the treatments could make dredging or construction very
difficult (e.g., if the sediments were solidified into concrete).
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12 Chapter 1
AND " : '.. -
• The in-place sediments do not act as a source for contamination of other media, such as
groundwater.
Possible in-.place treatments include: . j
• Immobilizing the sediments and contaminants by treating the sediments with fixatives to solidify
them or otherwise reduce bioavailability.
• Treating the sediments with neutralizers or binders to make the pollutants less biologically
available.
• Covering the sediments with barriers or sorbents to reduce transfer of pollutants from the
sediments to the water column and biota (e.g., capping). ,
Immobilization may only be a feasible option when sediments have already been isolated from the
water column by dikes in order to prevent the release of contaminants into the uncon fined environment.
The sediment removal option is viable when:
• The removal and disposal/treatment can be done so as to prevent unacceptable adverse impacts
from occurring (i.e., the adverse impacts from removal are less than those from leaving the
contaminated sediments in-place).
• Sediment removal is necessary for navigation or construction purposes.
• Viable disposal options exist.
If the decision to take action, either treatment or removal, is made, then technical considerations
need to be answered before a specific technique is chosen. Technical questions which-need to be
answered before in-place treatment or capping can be considered include:
••Will the sediments support the weight of a cap? !
• Will a cap have sufficient integrity to prevent its erosion by currents or waves?
• Will a cap significantly alter the location or speed of currents in the area?
• Will a cap sufficiently prevent the migration of contaminants to the surface and the effects of
bioturbation?
• Will contaminated sediments be a contaminant source to groundwater?
• Will mixing in the solidification agents cause significant releases of resuspended contaminated
sediments?
• What are the relative costs of feasible capping or treatment alternatives?
• To what extent does the alternative permanently isolate contaminated sediments from the
environment? . .
Most of the methods that have been used for in-place remediation are experimental. 'Of the
alternatives, capping has been carried out most frequently both iri the U.S. and Europe. Japan has; the
most experience with in-place immobilization. In the U.S., all immobilization has been done on dredged
sediments destined for off-site disposal areas, not on iri-place sediments.
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Introduction 13
Removal options consist mainly of conventional dredging and excavation techniques. The questions
that need to be addressed when selecting removal options include:
• What are the physical and chemical characteristics of the sediments to be dredged?
• What are the physical constraints at the dredging site or for access to the dredging site?
• What is the water depth at the site?
• What losses or resuspension of contaminants from the removal operation are acceptable?
• Is equipment available that will meet the minimum loss rate requirements and what are their
relative costs?
• If-the minimum loss rates cannot be achieved, what other measures can be taken to mitigate,
impacts (e.g., silt curtains, cofferdams, downstream sediment traps, etc.)?
Treatment Options
If sediment removal is undertaken primarily to reduce the environmental or human health risk of
leaving the sediments in-place, the sediments removed are more likely to be contaminated than those
removed by most navigational dredging. It is unclear whether the disposal facilities used for most
dredged material would be found acceptable for the highly contaminated sediments removed for
cleanup purposes. Some degree of treatment may be required before disposal.
In some cases, it may be possible to separate the sediments and/or the treatment residuals into
contaminated and uncontaminated fractions. Then, potentially, only the contaminated fraction would
need to be handled in a secure way, while the less contaminated fraction could either be disposed of
with few restrictions or, optimally, could be used in a beneficial way. This separation into contaminated
and uncontaminated residuals is a strong point of some of the treatment technologies, since it ca n reel -. c
ultimate disposal costs due to the reduced^volumes of contaminated materials that need to be J.spos^
of using more costly methods such as incineration or hazardous waste landfills. However, in general :o
realize this potential cost savings, the treatment technologies must be able to reduce chemical ^on
centrations, toxicity or mobility sufficiently so that the "uncontaminated" residuals can be classified *
non-toxic under TSCA regulations and non-hazardous under RCRA regulations. If the treatment
technology is not able to achieve the needed reductions, treatment, in some cases, could actuaiK
increase the volumes of "contaminated" material that has to be disposed of at a TSCA facility. Even in
this case, however, treatment may be warranted if it reduces the hazard posed by thesedimenu trom
unacceptable to acceptable levels.
Treatment options for sediments fall into the following categories:
• Contaminant/sediment volume reduction — This can be used in conjunction with other treat
mehts and involves reducing the total volume of contaminated sediment through mechanical
separation of the finer sediments from the coarser sand and gravel which is generally less
contaminated. Examples of such processes are hydrocyclones and soil-washing. Treatment can
then concentrate on the more contaminated fine material. If contaminant levels are low enough.
the coarse material may be employed for beneficial uses (such as construction fill material).
Thermal processes may also reduce sediment volumes through loss of organic and volatile
materials at high temperature. ,
• Contaminant immobilization — Involves mixing the sediment with materials that either bind
strongly to the contaminants to prevent their leaching or solidify the dredged material into
essentially unleachable solids. Solidifying agents such as Portland cement can be used. The
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14 Chapter I
sediment may also be mixed with siliceous hardening agents such as fly ash or blast furnace slag
and hardened into blocks or into a soil-like material. Calcium carbonate has been used to bind
to metals and increase the pH of runoff from dewatered dredged material, an 'effective treatment
for* controlling the metals in runoff from sediments placed in confined disposal facilities, for
example. !
• Contaminant destruction — Contaminant destruction technologies include biodegradation,
chemical detoxification and thermal techniques. Most of these techniques are appropriate for
dealing with organic contaminants, but techniques do exist for inorganic contaminants as well. In
general, processes which are designed for dealing with one type of contaminant (i.e., organic or
inorganic) ,can be made less effective by the presence of the other type. However, some
technologies are becoming available which destroy organics and incorporate inorganics in a solid
matrix such as glass (vitrification). Bacteria and fungi are known to metabolize some toxic organic
compounds, but their use has generally not been tested on a large scale. Ipcineration can be
carried out in either rotary kilns or fluidized bed reactors, both of which can handle a solid matrix.
Pyrolysis, the destruction of organics in the absence of air, is also' a technology that has been
applied to materials similar to contaminated sediments. Heat-related processes are all relatively
expensive. Chemical detoxification processes, such as KPEG, which is an alkali metal dechlorina-
tion process for chlorinated organic contaminants, are also being evaluated.
• Contaminant extraction, — Extraction technologies remove contaminants from sediments by
partitioning them in an appropriate extractant. In general, they are much cheaper than thermal
technologies, and have been more widely applied in hazardous waste cleanups. Various
proprietary processes use triethylamine (TEA), methanol, acetone, liquid piropane, or aqueous
acids as solvents. Few solvent extraction technologies remove both organic and inorganic
contaminants. The contaminants removed by the solvents may need to be further treated (or
incinerated) prior to disposal, and some of the solvent remains in the treated! sediments. Ideally.
the remaining sediments are sufficiently decontaminated that they can be disposed of in a routine
manner or used for beneficial purposes.
• Thermal separation — Physical mass and contaminant quantities in sediments can sometimes be
reduced by low temperature (200-1000°F) thermal treatment. Thermal separation is most effec-
tive for the removal of volatile and semi-volatile organics and volatile metals and the destruction
of cyanides. The removed contaminants may still require treatment and/or destruction, This
process works best for sediments with relatively low water and organic carbon content.
The above processes may require modification of the sediments before treatment. For instance.
most processes require that sediments be dewatered to some extent. The cost and effort involved in any
such preparation for treatment need to be considered when selecting treatment options.
The major information needs to decide on whether to use any of the above treatment options
include: " ' ,
• Are the sediments so highly contaminated that they must be treated no matter how they are to
be disposed of?
• Will treatment open up disposal options that were otherwise not available because of unaccep-
table environmental risks?
• Will the benefits of using the newly available disposal option offset the additional costs of
treatment (and disposal of any additional wastes generated)?
And in the consideration of which treatment alternative to use:
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Introduction
• Are the sediment contaminants primarily organic or inorganic?
• Are the organic contaminants all soluble in the same solvent?
• Are most inorganic contaminants likely to be removed by acid extraction?
• Will side effects such as volatilization be increased or diminished?
, • Are the binding agents that combine with the contaminants or the extractants compatible with
the sediment matrix or other contaminants? ; '
• Is there a commercial-scale system available?
• What is the cost of treatment relative to the available funds?
It can be inferred from the information needs that most treatment methods work well for either
organic or inorganic contaminants only. While this is generally the case, certain combinations of specific
organic and inorganic contaminants may be extractable with the same processes (e.g., the TEA process).
Disposal Options
Whether the contaminated sediments were treated and the success of the treatment process have
a great influence on the disposal options available for the remaining sediments. To determine the
disposal options, the characteristics of the contaminated sediments (treated or untreated) must be
compared to the criteria specified under various environmental statutes. It is in this area that the EPA
and the COE have developed procedures to assess the acceptability of certain disposal options. These
evaluation procedures are described in the next chapter.
The basic disposal options for contaminated sediments consist of:
• Unconfined aquatic disposal — This option is usually reserved for uncontaminated sediments
but could also be applicable if the sediments could be rendered inert by treatment.
• Benflcial uses —This option is applicable to minimally contaminated or uncontaminated sedi-
ments. Beneficial uses include beach nourishment and construction fill.
• Confined aquatic disposal (CAD) — This option consists of using clean sediments to cover over
contaminated sediments that were disposed of at an aquatic site. This can include excavating an
underwater pit in clean sediments, disposing of the contaminated sediments in the pit, and filling
up the rest of the pit with a layer of clean sediment. This option is viable if the site is one of-lo*
energy so that the cap is not eroded. The cap has to be of sufficient thickness so as to prevent
disturbance of the cap by burrowing aquatic organisms and possible contaminant migration
through the cap. The possibility of contaminant migration into groundwater should he minimized.
o Confined disposal facility (CDF) disposal -r- This option consists of constructing an in-water
dike to separate a portion of a nearshore area from surrounding waters. CDFs are frequently
constructed with part of the perimeter being an existing breakwater or land area, although they
are sometimes constructed to be man-made islands. Contaminated sediments are deposited
within this diked area. The dike walls can be constructed of a variety of materials having different
permeabilities. CDFs can lose contaminants through discharges through the dike walls or through
supernatant-decanting weirs or discharge structures. These losses can.be reduced through the
use of liners or systems to collect and treat leachate (water within sediment interstices) and
supernatant (water collected from above the settled sediments). CDFs may be suitable for
- moderately to highly contaminated sediments it" the appropriate design features are incorporated
to keep pollutant emissions to acceptably low rates.
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16 Chapter I
> Upland facilities — This option consists of a disposal facility resembling a landfill or waste
disposal facility. It can be constructed to various degrees of contaminant isolation through the
use of different materials for the walls, using additional liners, installing leachate collection layers,
etc. This option can be suitable for moderately to highly contaminated sediments if the ap-
propriate design features are incorporated to keep pollutant emissions at acceptably low rates.
i:
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Chapter 2
Existing Decision-Making Procedures
Chapter 1 presented some of the relevant issues that need to be addressed in managing con-
taminated sediments. A contaminated sediments issues framework was used to structure the
discussions. This chapter summarizes how these issues are being addressed under existing programs and
what decision-making procedures and protocols are currently in use on the national and Regional levels.
This chapter is organized according to the six broad categories of sediment management activities
discussed in the preceding chapter.
^
Finding Contaminated Sediments
In general, regular monitoring and surveillance of sediment contamination is uncommon,and
potential sediment contamination problems are more frequently identified by other means. These
means include reports of spills, discharge records, dredging records, fish kills, beach closings, previous
site characterizations, etc. Information from any of these sources can provide evidence that a potential
sediment problem may exist. Unfortunately, sources of these types do not generally provide information
on trends in sediment contamination and several of them (such as fish kills and beach.closings) indicate
problems only after they have become severe. A regular program of surveillance and monitoring
provides the most direct means for the early identification of potential sediment problems.
While regular monitoring of this type is not the norm, several regulatory frameworks currently have
provisions which do call for sediment surveillance and monitoring.
Clean Water Act
§115 of the CWA directs the EPA to "identify the location of in-place pollutants with emphasis on
toxic pollutants in harbors and navigable waterways..." and to act in conjunction with the COE to enact
their removal and disposal. The $15 million designated for this purpose has never been appropriated
to EPA. While the CWA does not preclude the identification of contaminated sediments in non-nav iga-
tional waters, the emphasis on navigational waters is clear. Justification for the active identification of
sediment contamination for other than navigational areas comes from general requirements to meet
water quality standards including waters where contaminated sediments adversely affect environmental
quality.
Within the CWA, special provisions are also made for toxic pollutant projects in the Hudson Ri%cr
and Chesapeake Bay, both of which authorize the identification ofvsediment-borne pollutants. For the
Great Lakes region, §118(c)(l) of the CWA authorizes the Great Lakes National Program Office to
carry out the U.S. responsibilities under the Great Lakes Water Quality Agreement and establish a
basin-wide surveillance and monitoring system for toxic pollutants. Monitoring and surveillance of toxic
sediments come within this scope.
17
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18 Chanter 2
Currently, most States conduct sediment monitoring only as part of special studies when contamina-
tion is already suspected. The most common trigger for initiating special sediment studies is the
appearance of higher than background fish tissue contamination levels.
A few States have adopted regular sediment monitoring within their water quality monitoring
programs. For example, New York has adopted a rotating basin intensive monitoring program of which
sediment monitoring is a regular part. Several other States (e.g., Pennsylvania, Washington, and
Michigan) are in the process of implementing similar programs.
Marine Protection, Research and Sanctuaries Act
Title II, §201 of MPRSA directs the Department of Commerce, the Treasury and the EPA, to
conduct a continuing monitoring and research program for the purpose of determining the effects of
dumping into marine coastal waters. §202 calls for the monitoring and research to assess the impact of
all pollutants on marine environments.
The Office of Marine and Estuarine Protection (OMEP) uses a tiered approach to developing
monitoring plans for specific sites (Fredette et al., 1986). In this approach, the expected severity of
impacts determines the intensity of the necessary monitoring program. The Regions have responsibility
for the development of site management/monitoring plans for individual dumpsites., Dumpsite monitor-
ing activities are generally not delegated to the States. Dumpsites are typically monitored on an annual
basis. :
Resource Conservation and Recovery Act
RCRA permittees are generally required to identify past releases of contaminants. They may then
be required to search for past and present contaminant releases, including those that have migrated
beyond the facility boundary. Also, interim status facilities may be required to clean up contaminated
sediments.
Comprehensive Environmental Response, Compensation, and Liability Act
Under Superfund, States and Regions identify sites with potential contamination problems for
possible inclusion on the NPL. These sites are assessed to determine the extent of hazards. While not
a direct monitoring program, these listings can provide first indications of possible sediment contamina-
tion, i
Great Lakes Water Quality Agreement
The Great Lakes Water Quality Agreement (GLWQA), Annex 11, calls for the monitoring of all
inputs, outputs and transformations within the Great Lakes system. This includes the monitoring of
sediments. It should be noted that the GLWQA itself is not legally binding. However, §118 of the CWA
gives EPA responsibility for overseeing U.S. progress in attaining the goals embodied in the GLWQA
The GLWQA calls for monitoring to be performed to fulfill three major goals:
• Ambient Monitoring — Used to establish the baseline of sediment quality and how it changes
over time. This can be used to indicate the relative importance of sediment contamination vs.
other system inputs.
• Assessment Monitoring—Used on a project-specific basis to determine compliance with existing
regulatory programs and to determine the need for taking remedial actions,,
• Research Monitoring — Used for the identification of emerging problems, the development of
standard protocols and the development of quality assurance/quality control procedures.
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Ejcistine Decision-Making Procedures 7 9
Both ambient monitoring and research monitoring can be used in the identification of new problem
areas.
Pugei Sound Estuary Program and Pug«t Sound Dredged Disposal Analysis
Monitoring within the Puget Sound area is performed under two programs. Under Puget Sound
Dredged Disposal Analysis (PSDD A), dumpsites approved for dredged material disposal and navigable
waterways are monitored. Under the Puget Sound Estuary Program (PSEP), monitoring of other areas
is performed usually as part of special case studies.
The State of Washington is currently in the process of developing a database of sediment monitoring
data for the Sound including the PSEP and PSDDA data as well as data collected as part of Superfund
site projects within the Sound.
Assessment Options
As mentioned previously, present sediment assessment decision-making protocols and procedures
are well developed for dredging-related projects but are generally poorly developed for other kinds of
contaminated sediments situations.
The majority of the assessment protocols presented in this section were developed specifically for
testing related to dredged material disposal under MPRSA §103 and CWA §404. Under MPRSA. a
general testing framework for dredged material has been developed and a similar framework is under
development under CWA. Furthermore, several of the Regions have developed Region-specific
protocols for use within these frameworks.
In Region X, the State of Washington is developing State sediment management standards and
dredged material management standards which will guide dredging activities, discharge permit develop-
ment, and remediation of sediments. These standards describe narrative processes for testing ind
evaluating each program activity, and also contain numeric sediment values as screening and trigger
levels for further study or action (including biological testing). These sediment quality criteria *ere
developed largely using the apparent effects threshold (AET) approach and include values generated
by the equilibrium partitioning (EqP) approach. (AETs are also being developed for San Francisco Bav
the Southern California coastline, and portions of the Great Lakes.) Because AETs are derived from
empirical data, these values are highly specific to a locale and should not be used on a broad basis
Regional screening levels are being developed by Region X for dredged material management. Several
states, such as Wisconsin and California, are also in the process of developing sediment quality criteria.
National criteria are under development by the EPA Office of Water Regulations and Standards.
Under the GLWOA the Sediment Subcommittee of the International Joint Commission (IJC) has
developed a method of sediment assessment aimed toward sediment contamination problems assoc ia i cd
with Great Lakes Areas of Concern (AOC). AOCs are contamination "hotspots" located within, the
Great Lakes Basin which have been given first priority for cleanup. Of the 42 identified AOCs cited by
the IJC, 41 have associated sediment contamination problems.
Comprehensive Environmental Response, Compensation aod Liability Act
Assessment and remediation of sediments at Superfund sites is carried out on a site-specific.
case-by-case basis. The Office of Emergency and Remedial Response (OERR), which is responsible
for Superfund activities, employs a risk analysis-based strategy in which the potential for environmental
and human health impacts is assessed. A1989 analysis of a preliminary OERR study suggests that 24*1
of the 1,175 NPL sites may have contaminated sediments. A subsequent evaluation of Records of
Decision (RODs) for 486 Superfund sites identified 69 sites with contaminated sediments. The ROD
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20 Chapter 2
is the official description of the selected remediation alternative for a site including a'discussion of the
reasoning behind the alternative selection. •
As part of the process of nominating sites to Superfund's National Priorities List (NPL), initial site
assessments are conducted on sites where a problem is suspected. Results from the initial site assessment
are used to determine a Hazard Ranking System (HRS) score. States, or EPA itself, collect information
on sites for scoring by EPA under the HRS. HRS scores are used by EPA to determine which sites
should be placed on Superfund's NPL as priorities for cleanup funds and for more detailed evaluations.
The HRS is a detailed, systematic scoring system for estimating the level of danger to human health
or the environment resulting from a given contaminated site. Individual .scores are aissigned for each of
four exposure pathways: surface water, groundwater, soil exposure, and air.
Within each of these pathways, three factors are considered: likelihood of release, waste charac-
teristics, and targets. The HRS provides numerous tables which give specific values! to be assigned for
individual factors according to the magnitude of various affecting sub-factors (e.g., annual rainfall.
container type, substrate type, chemical persistence, number of drums, distance to nearest well, etc.).
The HRS, as recently revised, evaluates both human health and ecological impacts due to con-
taminated sediment exposures. Human health impacts from contaminated sedimento occur through the
transfer of chemicals from sediments into fish and wildlife which are then consumed by humans.
The summation of each of the factors are combined to provide scores for the four exposure pathway*
above which are then normalized on a 0 to 100 scale. The final score is the mean of the scores from the
four pathways. ~ '
For sites on the NPL, EPA then carries out a detailed analysis of the risks posed by the site to human
health and the environment and the feasibility of various remedial action alternative!; to reduce the nsk
The analysis is carried out through the preparation of a Remedial Investigatio;n/Feasibiliry Stud>
(RI/FS). The document RiskAssessment Guidance for Superfund, Volume II • Environmental £i aiua ru •*
Manual (USEPA, 1989d) presents a broad framework for the assessment of human health ,*nJ
environmental impacts (Figure 3). This strategy is not designed specifically for sediments but, rather a
created for the purpose of assessing all exposure routes from contamination at Superfund sites (vkhn.fi
may or may not include sediments). Another guidance document pertaining to Superfund's
assessment process is Guidance for Conducting Remedial Investigations and Fea$U)uity Studies
CERCLA (USEPA, 1988c).
The first step of the process consists of identifying the contaminants of concern. Contaminants arc
divided into three non-mutually exclusive categories depending on whether they pose a threat, to
humans, the environment, or both. The second step quantifies the releases of the contaminants and
determines their migration paths and fates by use of fate and transport models and direct measurements
of environmental concentrations. The third step consists of the identification of the rates of exposure.
again divided into categories dependent upon the potential impacts. Finally, health and ecological
effects studies are undertaken so that a final evaluation of impacts can be made.
Under CERCLA, Superfund remedial action .must meet any Federal standards, requirements.
criteria, or limitations that are determined to be legally applicable or relevant and appropriate
requirements (ARARs). Water quality criteria established under §304 or §303 of the CWA should be
attained by cleanup where the criteria are relevant and appropriate. If sediment quality criteria are
promulgated and enforceable and meet all requirements of CERCLA and the National Contingency
Plan, then they can be considered as ARARs. Testing requirements mandated by the CWA §404 and
MPRSA §103 regulations could also serve as ARARs. If no ARARs exist for a particular contaminant.
site-specific levels are developed from risk assessments or guidance documents.
-------
Existing Decision-Making Procedures 21
Identify Contaminants of Concern
•Heafth j 'General Concern !• Environment
Specific ! (health & environ) •• Specific
Quantify Release Migration and Fate
•Fate and
Transport Models
' ••' \
•Measure Environmental !
Concentrations
r -
Identify Exposure Rates
•Hearth
Specific
•General Concern | • Environment !
(health & environ) ! Specific
Potently Exposed i
Habitats .. •
Human
Population -t-
Health Effects
Studies
Poteitialy Exposed Populations
Sport or
Commercial
Species
and Toots
Other Species i
Human Health I
Evaluation
i Environmental
' Evaluation
Figure 3. General Risk Assessment Framework Under Superfund (from USEPA,
1989d).
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22 Chapter 2
Interim sediment quality criteria for some non-ionic organic pollutants, derived from water quality
criteria using the equilibrium partitioning approach, were used at the Sullivan's Ledge Superfund site
in Massachusetts to identify contaminated locations and the areal distribution of contamination for
possible remedial action. At New Bedford Harbor, Massachusetts, risk assessments; were performed
based on sediment pore water concentrations of PCBs. At Waukegan Harbor, Illinois, modelled losses
of PCBs to Lake Michigan under various cleanup options were used to determine the cleanup level. In
Commencement Bay. Washington, sediment quality values derived from the AET approach (USEPA
1989c), in conjunction with site-specific biological effects data, were used to determine cleanup goals.
Marine Protection, Research, and Sanctuaries Act
Although the assessment protocol developed under MPRSA §103 is specifically for assessing
dredged materials for ocean dumping, it is a strategy with possibilities for broader application;
Permits for the ocean dumping of dredged material issued by the COE are reviewed by the EPA
according to several environmental criteria and either approved or denied by the EPA These criteria
have been codified in the Ocean Dumping Regulations (40 CFR 220-228), and EPA and the COE have
jointly developed a tiered protocol to determine whether dredged material from a particular project
meets the criteria. The protocol is presented in the Office of Marine and Estuarine Protection document
Draft Ecological Evaluation of Proposed Discharge of Dredged Material into Ocean Waters (the "Green
Book") (USEPA, 1990b). The draft protocol consists of four tiers. At each successive tier, the level of
effort involved is more intensive in both time and effort. However, the ability of successive tests to
provide definitive information for permitting decisions is greater.
Emphasis is placed in the protocol on evaluative techniques such as toxicity tests (bioassays) and
bioassessments. which are used as surrogates for potential environmental impact. Separate testing
schemes are required at each tier for benthic and water column biota. The general protocol is presented
in Figure 4. ;
At each of the first three tiers, three outcomes of the testing are possible:
• Information derived from testing is sufficient to conclude that proposed dumping is impermissible
without management action,
• Information from testing is adequate to conclude that proposed dumping is permissible provided
that all other aspects of the Ocean Dumping Regulations and other pertinent regulations are
met, or -.
• Information from testing is inadequate to make a decision and further testing is required at the
next tier.
At the fourth tier, only the first two outcomes are .possible.
The first tier has two objectives: to attempt to make a decision on compliance vising only existing
information* and to identify contaminants of concern for the dredged material.
In the evaluation of existing information on the sediments, the following factojrs are considered to
increase the likelihood that a sediment will be acceptable for open-water disposal:
• It is composed predominantly of sand, gravel, rock, or other natural bottom material with particle
sizes greater than silt, !
• It is found in areas of high current or wave energy, j "
• It is composed of grain sizes compatible with the material at the proposed disposal site,
-------
Existing Decision-Making Procedures 23
I-IEB i
TIERI
Ana^ easting information
and identify contaminants
okorwm
YES
T|ce it
Evaluate sedhient ind
&te condftons
YES
•m-» in
Tlcn III
Acute
and short-term
bioaccumulation studies
vpc
YES
vcc
YES
TIER IV
Chronic bbassays
andlon(H9rm
bJoaccurmJation studw
Choose open-water
disposal
Reject open-water
disposal w/out
special management
Figure 4. Dredged Material Testing Framework Under MPRSA.
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24 Chapter 2
• The dredging project is isolated from known or suspected, current or historical contaminant
sources.
If the converse of these are true (i.e., a fine material close to a contaminant siource), then the
acceptability of open-water disposal is less likely. Situations between the two may require testing at the
next tier. ';
Identification of contaminants of concern must be accomplished on a case-by-case basis. The
process begins with an examination of existing information which may aid in their identification. Such
information can consist of previous dredging records, field studies, various toxicity and environmental
data bases, spill records, etc. The more complete the information, the more likely that a regulatory
decision can be made at the first tier. Initial testing for the presence and concentrations of contaminants
within the sediments may be done to augment the information acquired from existing sources.
Contaminants of concern are then identified on the basis of:
• Presence in the dredged material, i
f>
• Concentration in the sediments relative to background concentrations, i
• Toxicological importance, j
• Tendency to persist in the environment, .
• Potential for bioaccumulation. ,'
Tier II consists of an evaluation of the chemical and physical characteristics of the dredged material
and the overall environmental conditions at the site. Water column impacts are evaluated by comparison
of dissolved contaminant concentrations after initial mixing with the applicable water quality criteria.
If water quality criteria are not available or if synergistic effects among several chemicals are suspected.
then toxicity testing at Tier III is necessary, as explained in 40 CFR 227.13. Evaluation of beithic impacts
is less straightforward at Tier II. Bioavailability of non-polar organic contaminants is evaluated on the
basis of theoretical bioaccumulation potential,(TBP) and/or sediment quality criteria, when they are
promulgated in the Federal Register. However, this type of calculation cannot be performed for some
types of contaminants (e.g., polar organics, metals, organometals, etc.). Bioaccumulation of con-
taminants by benthic organisms must be evaluated at Tiers III and/or IV if:
• Any of the contaminants of concern is other than a non-polar organic contaminant for which
calculation of TBP is not valid,
OR
• All contaminants of concern are non-polar organic in nature but TBP values calculated exceed
those for the reference sediment.
Testing at Tier II will either be adequate to make a regulatory decision or may indicate the need
for additional testing at Tier III.
Tier III evaluations consist of acute bioassays and bioaccumulation tests on appropriate sensitive
organisms to determine the likelihood of adverse environmental impacts. Results are compared to those
from identical tests run with reference sediments. For the bioassays, mortality is taken as the biological
endpoint due to ease of interpretation. Benthic bioassays are conducted using siite sediments and
representative benthic organisms. Water column assays are performed with appropriate water column
organisms.
-------
Existing Decision-Making Procedures 25
Benthic bioaccumulation studies are performed over 10-day (for metajs) and/or 2S-dav (for other
contaminants) periods. Tissue concentrations are compared to two endpoints:
• FDA Action Limits for Poisonousiand Deleterious Substances in Fish and Shellfish for Human
Consumption (protective only of human health from fish consumption),
• Tissue concentrations of organisms similarly exposed to reference sediments. >
If FDA limits are exceeded, the dredged material does not comply with the bioaccumulation aspects
of the benthic criteria in 40 CFR 227.13. The decision of whether such material might be allowable for
-ocean disposal under MPRSA is beyond the scope of the Green Book.
If FDA limits are not exceeded, then comparison is;made with reference tissue concentrations. If
reference tissue concentrations are not statistically exceeded, the dredged material complies with the
bioaccumulation aspects of the benthic criteria and the material can be considered for ocean disposal
(given that benthic toxicity effects and potential water column impacts have also been considered). If
the reference tissue concentrations are statistically exceeded, case-specific criteria should be developed
by the local COE and EPA authorities which account for case-specific factors. These factors include
and are affected by the number of organisms which are affected, the propensity for the chemical to
bioaccumulate, the number of chemicals which bioaccumulate, the magnitude with which bioaccumula-
tion exceeds reference bioaccumulation, etc. Based upon consideration of these factors, one of the
following decisions is reached:
• The dredged material complies with the case-specific criteria and ocean disposal is acceptable if
toxicity and water column tests are also passed, or
• The available information is insufficient to determine compliance with the bioaccumulation
aspect of the benthic criteria.
Insufficient information to make a regulatory decision indicates that testing at the fourth and t'inal
rtier is required.
Tier IV testing continues and augments bioassays and bioaccumulation studies conducted at
Tier III. Whereas the 10- to 28-day studies conducted under Tier III may not be of sufficient duration
to reflect steady-state conditions (e.g., they may only reflect initial tissue concentrations), Tier IV tests
are designed to reflect long-term exposures of the most sensitive organisms to the expected sue
conditions using the most sensitive indicators (e.g., reproduction, survival, etc.). Design of Tier IV
bioassays is project-specific, depending upon the nature of the material, the organisms present and the
contaminants of concern.
Bioaccumulation studies at Tier IV are likewise designed to reflect steady-state conditions.. Samples
can be collected from laboratory specimens exposed to the dredged material or from specimens
collected in the field, if appropriate (field collected organisms are those collected in the vicinity of the
proposed disposal site). Tissue concentrations are compared successively to three endpoints:
• FDA Action Limits (as described above),
• Tissue concentrations from reference material, or
• Tissue concentrations from field collected benthic organisms.
If FDA limits are exceeded, the dredged material does not comply with the bioaccumulation aspects
of the benthic criteria in 40 CFR 227.13. The decision of whether such material might be allowable for
ocean disposal under MPRSA is beyond the scope of the Green Book. Non-exceedence of FDA action
limits leads to comparison with reference tissue concentrations. Non-exceedence of reference tissue
-------
26 Chapter 2
concentrations is considered compliance with benthic criteria and the material can. be considered for
ocean disposal (given that benthic toxicity effects and potential water column impacts have also been
considered). If reference tissue concentrations are exceeded, then comparison with field tissue con-
centrations is required. If field tissue concentrations are not exceeded, then the material can be
considered for ocean disposal. If the material is in exceedence, then the results of bioaccumulation and
bioassay testing are weighed considering the following factors: ' j
! ' '
• The number of species for which criteria are exceeded, [
• The number of contaminants for which criteria are exceeded, I
• The magnitude of exceedence of reference concentrations,
• The lexicological importance of the contaminants,
• The diversity of the species for which criteria are exceeded, \
I >
• The propensity for contaminants to biomagnify.
After the weight of these factors is considered, one of the following decisions must be reached:
• The dredged material complies with the criteria of §227.13(c), or '
• The dredged material does not comply with the criteria of §227.13(c). ;
Clean Water Act
The Office of Wetlands Protection (OWP) oversees the CWA §404 program which regulates the
discharge of dredged or fill material in §404 waters. Currently, there is no broadly applied analog to the
Green Book for MPRSA decisions. Evaluations are handled on a case-by-case basis. However, COE
and OWP are currently in the process of developing a §404 testing manual for dredged material §404
Testing Manual) which will use the same tiered testing strategy as the Green Book: with appropriate
testing procedures for §404 waters.
The current national guidance for §404 testing procedures is contained in the §404(b)(l) guidelines
These guidelines provide only a general framework under which testing is to be performed. Several
Regions^have developed guidance for use within their jurisdictions (i.e., Regions I, V, IX and X). The
Regions' guidances are in various stages of implementation. The Regional guidance documents
generally follow the pattern of the Green Book with modifications for freshwater systems and kx-al
biota and chemicals of concern.
Subpart G of the §404(b)(l) guidelines sets forth the following steps in the evaluation process
1. General Evaluation of the Material — This step examines existing information (i.e., records ol
spills, discharge records, fish tissue contamination, etc.) and general material characteristics (i.e..'
grain size, relative carbon content, etc.) to determine if there is "reason to believe" that the
material needs to be tested for potential adverse effects.
2. Chemical and Biological Testing — If the first step indicates possible contamination, then fur-
ther chemical and biological testing may be carried out. This includes chemical characterization
of the sediment, water column effects (elutriate) testing, and benthic effects testing. Under some
circumstances, benthic community structure analyses of the dredging and disposal sites may be
required. ,
-------
3. Evaluation of Physical Effects — This step examines the possibility that the placement of the
dredged material-may affect the physical and biological environment of the dumpsite. This in-
cludes changes in the substrate, hydrology, salinity, etc. » • '
Under the §404 program, unlike the ocean dumping program, discharge sites for dredged material
are specified on a project- or permit-specific basis. As with the assessment of dredged material the
SSlt^ ? 'Si6 !mpaC~ °n thC discharSe site are done in accordance with the requirements of the
§404(b)(l) Guidelines. One of the primary requirements of the Guidelines is that no discharge can be
permitted if there is a practicable alternative with less adverse impact on the aquatic environment
(unless the identified alternative poses significant .environmental problems). In addition no discharge
can be permitted under the Guidelines if it: violates State water quality standards; violates toxic effluent
standards; jeopardizes the continued existence of an endangered species; or violates any requirements
enacted to protect any federally-designated marine sanctuary. Discharges are also not in compliance
with the Guidelines if they will cause or contribute to significant degradation of the waters of the U S
Finally, the Guidelines require that all appropriate and practicable measures to minimize potential harm
to the aquatic ecosystem be taken. .
Region I Testing Guidance under CWA §404 and MPRSA §103
Regional guidance which supersedes the Green Book has been developed by Region I EP A ,n
conjunction with the New England Division of GOE. The document. Guidance for Performing 7V,« *
Dredged Material to be Disposed of in Open Waters, uses the tiered strategy of the Green Book hut
specifies the selection of appropriate bioassay organisms and chemical analytes.
This document is important in that, unlike the Green Book, it applies to both MPRSA §n»i ^
CWA §404 waters. The document was developed with the full cooperation of New England COB'j dc *
by the National Marine Fisheries Service and the U.S. Fish and Wildlife Service.
Within the document, Region-specific protocols are given for:
• Selection of sampling sites for dredged, reference, and control sediments.
• Specific requirements for physical and bulk chemical analysis of sediments including j „%« '.«
chemicals of concern and analytical detection limits.
• Tiered evaluation testing requirements consisting of:
- A liquid phase assay,
- A suspended paniculate assay,
r A whole sediment assay, and
- Bioaccumulation analysis,
• Elutriate testing procedures, and
• A set of quality assurance procedures for all of the above activities.
Open water disposal at Regional disposal sites (of which there are 13) is overseen by the Region I
Marine and Estuarine Protection Section. All other dredge and fill activities are overseen h% the
Region I Wetlands Protection Section. '•'.''
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23 Chapter 2
Region IX Testing Guidance under MPRSA §103
Region IX. in cooperation with COE, has issued specific guidance for dredged material tesi ine in
the document EPA Region 9 General Requirements for Sediment Testingof Dredged Material Proposed
for Ocean Dumping. This guidance became effective in August 1989. '
The guidance is largely similar to that issued by Region I in its scope but differs in the specific
chemicals of concern and bioassay species which are recommended for testing. Again, the guidance
utilizes the Green Book's tiered strategy. ,
Region V Draft Interim Testing Strategy for Navigational Dredging
The EPA Region V Environmental Review Branch, in conjunction with Great Lakes COE district
offices, has produced interim guidance for sampling and testing efforts related to navigational main-
tenance dredging under CWA §404 (USEPA, 1988b). This strategy is being developed as guidance for
compliance with NEPA and other environmental regulations, as well as CWA §404. The guidance is in
interim form and the COE currently has the option of choosing whether or not to follow it. Region V
currently works on a case-by-case basis and may or may not require that the procedures in the guidance
be used and may also use the UCGuidelines and Register/or Evaluationof Great Lakes Dredging Projects
(IJC. 1982) as part of the approach (see "IJC Dredging Guidelines" later in this chapter in section on
disposal). The interim testing guidance uses a combination of chemical and biolojpcal tests (Figure 5).
The guidance divides the process of testing into five basic stages:
• Pre-design stage—This stage consists of the collection of relevant historical information on the
dredging project and the "initial delineation" of sediments within the dredging project area into
three categories based on the probable extent and severity of contamination. The three categories
are:
- Type I — Sediments with a very low probability of contamination problems %vhich are
generally coarse-grained and located well away from contamination sources.
- Type II—Sediments which are in the transition zone between Type I and III sediments and
for which the level and extent of contamination is not clear based on inidal information (the
so-called "gray area").
- Type III — Sediments which are known to be heavily contaminated based on historical data.
These are generally fine sediments located in close proximity to contamination sources.
• Preliminary design stage — This stage consists of the design of a sampling and testing strategy
based upon the results of the first stage analysis. Emphasis is placed on the characterization of
Type II sediments.
• Final design stage — The preliminary design is put through a regulatory review for possible
revisions. This review must precede the execution of any part of the actual sampling and testing.
• Execution —The sampling plan and testing are implemented following procedures and protocols
outlined in the guidance document.
• Reporting of data — Again, specific protocols and procedures are presented for the reporting
of sampling and testing results. • ,. , v
i -
Region X/Puget Sound Dredged Disposal Analysis :
The Puget Sound Dredged Disposal Analysis (PSDDA) was developed in a comprehensive inter-
agency effort that began in 1985 and was completed in 1990 (PSDDA, 1989a and 1989b). PSDDA's
-------
i Source I
j : '
1 | i
i History \
i
J Preliminary [_
.Determination i
Type!
Type II j Type III
Sediment Testing
Beneficial use
or open water disposal
Site analysis
Unsuitable for
unconfined
disposal
i
Elutriate
Pore Water
Settle/filter
! r
| l Control i | 401 /
rj requirements H
Figure 5. EPA Region V Testing Strategy for Navigational Dredging Projects
(from USEPA, 1988b).
-------
JO Chapter 2 •.
focus was on identifying and managing disposal sites and developing evaluation procedures to determine
suitability for unconfined. open-water disposal of sediments dredged from federal and non-federal
navigation projects throughout the Sound. It was developed as a site-specific application of the COE
strategy (which is described in the section of this chapter on disposal) that incorporates the requirements
of the CWA §404(b)(l) guidelines and general and specific criteria of the MPRSA guidelines.
Procedures for regulating/managing sediments that are unsuitable for open-water disposal are currently
under development.
PSDDA describes comprehensive evaluation and monitoring requirements. Both are basically
tiered systems like the MPRSA (USEPA, 1990b) and IJC (IJC, 1982) .protocols and are concerned
with managing the "effects" of chemical contamination rather than the presence of contaminants. It is
the PSDDA evaluation procedures for determining the acceptability of dredged material for open-
water disposal that have received the most attention. The procedures address sampling requirements.
chemical and biological testing, test interpretation, and disposal guidelines. PSDDA's testing and
decision framework is shown in Figure 6.
A tiered testing approach was adopted by the PSDDA agencies. Tier I is a "reason to believe" review
of the existing data looking for evidence of contamination. Tier U, includes chemical testing of sediments
for 58 chemicals of concern. Sediment concentrations of these chemicals are compared to screening
levels (SLs) and maximum levels (MLs) for each contaminant. Concentrations below the SL indicate
that open-water disposal is acceptable. Concentrations above the ML indicate that open-water disposal
is unacceptable. Concentrations between the two require biological testing at Tierlll using a prescribed
battery of tests including acute toxicity and, if necessary, bioaccumulation tests. Tier IV tests are possible
when concentrations exceed MLs but tests for this Tier have not yet been fully defined.
SLs and MLs are derived primarily from AET values, but also include EqP derived values (PSDDA
1989b). AET values are derived using matched chemical and biological data from selected reference
(uncontaminated) sites and a series of contaminated sites. For each constituent of interest, the AET is
determined as the highest sediment concentration that is not associated with a statistically significant
difference in one or more biological parameters (e.g., total abundance, diversity, sediment toxicity)
between reference and contaminated sites. However, the AET values that have been calculated for trie
Puget Sound area are location-specific, and according to EPA's Science Advisory Board, should not be
used as National sediment quality criteria (USEPA, 1989e).
Other Regions
Other Regions which have developed their own testing guidance use a variety of approaches. Most
of these approaches use the Green Book as a starting point. The following Regions are presented as
examples of typical programs. , .
Region II has no Regional protocols for testing under the Green Book. In MPRSA §103 waters.
the 1977 Green Book is applied awaiting finalization of the current draft. In CWA §404 waters, the
§404(b)(l) guidelines are used, except in the Great Lakes where a combination of the reference
approach found in the EPA Region V document Guidelines for the Pollutional Classification of Great
Lakes Harbor Sediments (USEPA, 1977) and the approach found in the IJC's Guidelines and Register
for Evaluation of Great Lakes Dredging Projects (IJC, 1982) are utilized.
Region III applies the Green Book to ocean dumping activities. Sediment assessments for §-404
waters are performed using the Extraction Procedure (EP) toxicity test, and other tests as necessary.
in addition to the §404(b)(l) Guidelines'requirements.
Region IV applies the Green Book in its ocean dumping program arid loosely applies the Green
Book approach to §404 waters. For the Ohio River in Kentucky, a set of guidelines known as the
-------
TIER I
Aaaeaa Existing Information
3T
YES
TIER II
Conduct Chemical TMU
TIER III
Standard Biological TMU
Ar«dl*pOMl
YES
Ai» «U cb*mlc«to o*
concern b»tow
•ciwnlng !•«•!•?
YES
NO
data adequate?
YES
YES
Uiwultabto tor unoonnn«d
op«n-wat»r dtopoaal
L
Sultabla for uneonfinad
opan-water disposal
Figure 6. Dredged Material Testing Sequence Under PSDDA (after PSDDA, 1989b)
-------
32 Chapter 2
"Louisville Guidance" has been developed based on an approach borrowed Ixorn the Region V
Guidelines for the Pollutional Classification of Great Lakes Harbor Sediments (USEPA, 1977), which is
a reference approach. ' ','
,*'
Region VII contains no coastal States and is, therefore, not affected by MPRSA regulations. All
dredge and fill reviews are managed under CWA §404(b)(l) guidance with no specific Regional
guidance as exists in some other Regions.
UC Sediment Subcommittee Sediment Assessment Strategy
Although this sediment assessment approach is not currently used within EPA, it deserves note as
one of the few well developed assessment schemes that are aimed specifically at contaminated sediments
outside the navigational dredging context.
The sediment assessment approach proposed by the IJC Sediment Subcommittee in the document
Procedures for the Assessment of Contaminated Sediment Problems in the Great Lakes (IJC, 1988a) is
basically a multi-pronged approach designed for use in fairly large-scale remediation projects where the
remediation costs and effort are expected to be relatively high, thereby justifying a comprehensive
evaluation. Chemistry, toxicity, and infaunal community structure form the basis of a three-pronged
evaluation approach.
The strategy is implemented in two stages (Figure 7): ; .
• Stage I: Initial Assessment—Only in situ methods are employed. These include a limited physical
description of sediments, bulk chemical analyses (nutrients, metals, persistent organics, etc.), carp
and benthos contaminant body burdens and external abnormalities, and benthic community
structure (qualitative estimates at the family level). . ;
The criteria for passing to the next phase include any one of the following:
- Sediment metals concentrations exceed background levels,
- Concentrations of persistent organics are above detection levels in sediments or fish and
benthos tissues,
- Absence of a healthy benthic community,
- Presence of external abnormalities on fish.
• Stage II: Detailed Assessment — Stage II is conducted in four phases. The information for each
previous phase should be used to guide and limit the requirements for the succeeding phases.
Npne of the phases should be skipped and all tests should be completed, although their extent
may be limited by the results of previous ones.
- Phase 1 — A 3-dimensional map of the study area is created so that dejiositional areas and
areas of homogeneous sediment characteristics can be mapped to guide further sampling.
- Phase 2 — A more detailed collection of benthic fauna is made along with detailed
measurements of surficial chemistry.
- Phase 3 — Surficial sediments, sediment cores, and indigenous fish are collected from sites
which are shown to be impacted from the results of Phase 1 and 2 tests. Bioassays are
conducted using the sediment samples, and detailed chemical characterizations of the
sediments are made. Detailed histopathologic examinations are made on fish, focusing on
liver tissues.
-------
Existing Decision-Making Procedures 33
Stage
Initial Assessment
Stage II
Detailed Assessment
'Geographic description
i •Physical and chemical
; sediment characteristics
[ «Carp and benthos
; body burdens and
i abnormalities
: •Qualitative benthic
| community structure
Phase 1
•Physical mapping
Phase 2
•Surficial sediment
chemistry
•Detailed benthic
community structure
Phase 3
•Core sampling
•Bioassays
•Detailed chemistry
•Fishhistopathology
Phase 4
• Sediment dynamics
Figure 7. IJC Sediment Subcommittee Sediment Assessment Strategy. (IJC,
I988a) ^7 v
-------
J4 Chapter 2 , ,
- Phase 4 — Sediment dynamics are studied in detail to determine the potential impacts of
sediment resuspension. movement to other areas and redistribution of contaminants through
the water column. This information is considered essential for the development of remedial
action plans
Prevention and Source Controls
At the national or regional level, sediment contamination can be controlled only by the widespread
application of one of two basic types of restrictions:
i
• Restrictions on the production, distribution, or use of a chemical, or . j
• Restrictions on the amounts of a chemical that can be released to the environment.
The first restriction applies primarily to chemicals that are produced for a certain use, while the
second applies primarily to by-products or wastes of production or use. By judicio>us applications of
these restrictions, EPA can achieve considerable control over contaminants that are or have the
potential to be ubiquitously distributed. This then leaves individual contaminated sites to be dealt with.
On a local or site-specific basis, however, specific actions can be taken to deal with particular sites.
It is for these situations that most of the criteria and procedures have been developed.
National or Regional Scale
On the national or regional scale, four laws and an international agreement hsive provisions for
controlling sediment contamination: TSCA, FIFRA, CWA, CAA and the GLWQA, The first two la«*
are concerned primarily with the production and use of particular chemicals, the latter two with *aste»
or by-products released to the environment. The GLWQA has provisions addressing all aspects of
environmental quality in the Great Lakes. The major provisions, criteria, and procedures that/can'be
used in the control of sediment-related contaminants are described below.
Toxic Substances Control Act
One of the most powerful authorities for regulating toxic substances in contaminated sediments a
found in §6 of TSCA. Under this Section, EPA can prohibit or limit the production and distribution of
any chemical substance or mixture if it poses or could pose an unreasonable risk of injury to health or
the environment. Actions taken under this section include the ban on production of polychlorinaied
biphenyls (PCBs), a wide-spread chemical contaminant (e.g., in Great Lakes and Hudson River
sediments). Sediment contamination was not one of the major considerations in banning the production
of PCBs, but the effects of sediment contamination were considered.
There are no uniform criteria or methods under TSCA that are applied to determine when
unreasonable risk of injury to health or the environment has occurred or might occur. On a chemical-
by-chemical basis, EPA makes a decision based on a wide variety of considerations including the
chemical's use, distribution in the environment, persistence, toxicity and other factors. TSCA testing
procedures are Being revised to include three tests with exposures through sediments: a 30-day tadpole
subchronic toxicity test, a 14-day chironomid toxicity and bioaccumulation test, and a site-specific
aquatic microcosm test which includes natural sediments. Once a decision is made, based on the weight
of evidence from all sources, procedural regulations require that a Notice of Proposed Rulemaking be
published in the Federal Register so that public comments can be received prior to taking action. In
extreme cases, however, public notice is not required.
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« ' w •
Existing Decision-Making Procedures JS
Federal Insecticide, Fungicide, and Rodenticide Act
All uses of biocides are regulated by the EPA under FIFRA Before a
U.S., it must be reviewed and registered by EPA for one or more specif!
herbicide or disinfectant. The registration process is the method by which El
a chemical s toncity to humans and non-target plants and animals efficacv *nH >™v~ ,"c "°
i — The nature of possible hazards is determined by examin-
cologicaldata(e.g.,LCsos,NOELs).
i — Quantitative relationships are determined between
lie use of safety factors.
rate governing factors such as intensity.
"' * robabflity -
abo« <"«ta is combined ,o produce an eslimate of the prob-
und e'
Based upon the analjsis, the Ecological Effects Branch (EEB) issues a statement asse^in. ,h,
ecolopcal nsk from the use of the pesticide and recommends on. of seveSl ^0^ acUcn" «
• Require additional data,
• Require restricted use classification to reduce risk,
• Require use restrictions on label,
• Initiate special reviews based on risk criteria, or >
• Recommend against registration.
In those cases where an endangered species is indicated as one of the soecies at risk in* FPR
?? H w'u, vecNati°nal Madne Fisheries S"** (NMFS) ^ the appro^ Rein 0> t
Fuih and WOdhfc Service (USFWS). USFWS and/or NMFS
one ofeio the;USFWS a^ NMFS opinion, the EEB can reco^cnd
1. Label restrictions designed to eliminate risks to endangered species,
2. Recommendation against registration of the pesticide, or .
COn$ukatioD ^^ US^S or NMFS if ^ere is disagreement with the final
used°and SSJE?1? f^ ' P^"" has ^^ set- ^"nation regarding how it is to be handled.
used, and deposed of . hsted on the label. Any deviation from the instructions found on the label ,s
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36 Chapter 2
considered a violation of law and is subject to penalties. When necessary, use of a pesticide is restricted
by limiting who can use the product or how and where the product can be applied. Examples of
restrictions include allowing only certified applicators .to use the product or prohibiting its use within
25 feet of a body of water.
If a pesticide is commonly found in contaminated sediments, its registration can be questioned by
any interested person who submits a petition with information supporting the need for reevaluating the
product's use. EPA uses a Special Review to reevaluate a product's registration. Criteria for Special
Review include (40 CFR 154.7): . ' .
• Does a product's use result in residues in the environment of non-target organisms at levels which
equal or exceed concentrations acutely or chronically toxic to such organisms,, or at levels which
produce adverse reproductive effects in such organisms, as determined from tests conducted on
representative species or from other appropriate data?
• Does a product's use pose a risk to the continued existence of any endangered or threatened
species? •
• Does its use result in the destruction or other adverse modification of any critical habitat of a
threatened or endangered species?
• Does it otherwise pose a risk to humans or to the environment which is of sufficient magnitude
to merit a determination whether the use of the product offers offsetting social, economic, and
environmental benefits that justify its continued use?
Upon completion of the Special Review, the Agency may initiate formal proceedings to cancel or
reclassify use of a product, or to return the pesticide to the registration process.
An example of a special review based on probable effects on benthic organisms is the special review
given to tributyltin (TBT) compounds (USEPA, 1987). OPP is considering restrictions on the/use of
TBT compounds in marine paints based on the effects of these compounds on benthic organisms. Since
TBTs are hydrophobic, sediments are considered to be a significant repository and source for these
compounds. Sediment exposures are considered in the risk assessment for TBTs.
Clean Water Act :
There are no provisions in the CWA that allow nation-wide direct discharge limitations tor
particular chemicals. The closest provisions to national limitations are the effluent guidelines developed
for determining Best Available Technology (BAT) standards for various industries. litecause discharge
limitations that are based on the effluent guidelines are constrained by treatment technology, discharge
limitations based on State water quality standards (water quality-based limits) are frequently the more
protective way to implement limitations on particular chemicals.
It is possible that sediments could continue to be contaminated by point source discharges even
where water quality-based permits have been issued and permit limitations are being met. Water quali ty
criteria do not consider the sediment pathway and hence may not be stringent emough to protect
sediment quality. This is the result of sediments' ability to store contaminants.
Water quality criteria are set on water-borne exposure of organisms (including humans) to con-
taminants, and do not consider the accumulation of contaminants in sediments. For many chemicals.
failure to consider contaminant accumulation in sediments may not be important, but for relatively
insoluble toxic chemicals that sorb to sediment particles, relatively low continuous inputs may result m
extensive sediment contamination. Sediment quality criteria that have the same force as water quality
criteria may need to be formally implemented in order to control such discharges, and evidence of
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Existing Decision-Making Procedures 31
wide-spread contamination by a few chemicals could set priorities on those chemicals for which sediment
quality criteria are needed. Once EPA establishes recommended sediment quality criteria they could
be incorporated into State standards and could be used to further limit discharges. Once'adopted as
standards, they can be used to require more stringent effluent limitations than BAT under the provisions
ofCWA§301(b)(l)(C). .pruviMoiB
Clean Air Act
Existing implementation of the CAA focuses primarily on the establishment of national ambient
air quality standards (NAAQSs) and does not address the airborne .toxics deposition that results in
sediment contamination. Seven major ubiquitous pollutants have NAAQSs: paniculate matter, sulfur
oxides, carbon monoxide, nitrogen oxides, ozone, volatile organic compounds (mostly hydrocarbons)
and lead. The CAA also requires EPA to set uniform national maximum emission standards for each
industry. These New Source Performance Standards (NSPSs) are set based on costs, energy require-
ments, and public health and welfare considerations.
With sufficient evidence that airborne emissions are causing sediment contamination, and are thus
threatening public health or welfare, both NAAQSs or NSPSs might be revised to be more restrictive
for problematical sediment contaminants. There are, however, no criteria or methods currently avail-
able for accomplishing this. '
Great Lakes Water Quality Agreement
The GLWQA between the United States and Canada contains a number of provisions that apply
to contaminated sediments within the Great Lakes basin: *
• Annex 1 provides a process for setting specific objectives for persistent toxic substances which
have been found in or which have the potential to contaminate water, sediments or aquatic biota.
• Annex2providesthebasisforthedesignationoftheAreasofConcernintheGreat Lakes Basin.
Forty-oneof the 42 Areas of Concern are suspected of having contaminated sediment problems.
• Annex 7 calls for coordinating the U.S. and Canadian programs regulating dredging and dredged
material disposal. ,
• Annex 11 calls for surveillance and monitoring programs of all media including sediments in order
to assess achievement of the specific objectives, the evaluation of water quality trends and to
identify emerging problems.
• Annex 14 calls for the two countries to address a wide range of contaminated sediment issues
including assessment, remedial options, disposal and management programs.
The implementation of the provisions of the GLWQA are overseen by the IJC and its boards and
committeeSi
Locator Site-Specific Scale
In the majority of situations, national or regional scale restrictions will not be necessary to effectively
prevent sediment contamination. Local, or site-specific limitations are possible under a number of
1 environmental statutes, including the CWA, RCRA, and CERCLA. Most of the decisions under these
statutes (except CERCLA) relate to permitting actions on individual facilities for the discharge.
emission, or releaseof potential sediment contaminants. The major provisions, procedures, and criteria
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38 Chapter 2
that apply to the prevention of sediment contamination under each of these statutes are described
ll/»Irni/
below.
Clean Water Act
Currently, wasteload allocations (WLAs) are developed with achievement of water quality criteria
and water quality standards as their primary goals. Until recently, sediment quality was not considered.
Using appropriate sediment quality monitoring and models in conjunction with sediment criteria WLAs
could be redone to protect sediment and water quality. Under such a system, the more stringent of the
two allocation levels (water quality-based or sediment quality-based) would form the basis for permit
limitations and nonpoint source allocations.
As mentioned previously, the CWA has provisions for including water quality-based considerations
into permits for industrial and municipal dischargers. Total maximum daily load (TMDL) could be
calculated for the segments in which sediment quality criteria were being exceeded, and WLAs could
be done for each point source discharge using models with capabilities for dealing with sediment fate
and transport. Water quality-based permit limits could then be written for each of the dischargers
limiting the discharges to levels that maintain sediment quality.
Nonpoint source control for the protection of sediment quality can be somewhat more problematic
Currently, nearly all States and Territories (e.g., Puerto Rico) have developed assessment and manage-
ment reports under §319 of the CWA which have been reviewed and approved by EPA. Upon approval
of their §319 reports. States receive monies for nonpoint program development, but, to date, none of
this money has been used directly on projects related to sediment remediation.
CWA §319 does not provide the EPA with direct regulatory authority to control nonpoint sources.
Instead, States are to include plans for the implementation of best management practices in their §319
assessment reports to reduce nonpoint source loadings. The enactment of these plans is left to. State
discretion. EPA authority for nonpoint source control may indirectly exist in §303 (d) of the CWA.
Under this section, EPA can require States to establish TMDLs for waters not meeting beneficial uses
If the State does not develop TMDLs, then the EPA must develop them.
Within Region X, a multiple state TMDL for dioxin is being performed in the Columbia River with
sediment contamination being considered.
The States have the authority to adopt sediment quality criteria and standards. The State of
Washington is preparing to issue sediment management standards including numerical sediment criteria
derived largely using the AET method.
Under §301(h), the Office of Marine and Estuarine Protection has developed a benthic assessment
methodology for assessing the quality of the marine environment and monitoring changes to the
environment that might result from the discharge of municipal wastes. The methodology is used to
modify §301(h) waiver conditions when adverse environmental effects are detected.
Comprehensive Environmental Response, Compensation and Liability Act
The need for remedial action under CERCLA authority is determined through the Remedial
Investigation/Feasibility Study (RI7FS) process, an activity generally reserved for sites on the NPL If
remedial action requires limited resources ($2,000,000 or less, or less than 12 months), such action could
be taken on a site, even if it is not on the NPL, if the site poses an immediate threat to human health
or the environment. The HRS, as recently revised, may aljow sediment contamination levels to be used
for evaluating contaminated aquatic sites and for confirming releases to surface waters. The ultimate
impact of the new HRS on the listing of sites with contaminated sediments is not yet clear.
-------
Resource Conservation and Recovery Act
U?d" ^^ fcorrective action Pro^ions can be applied to any RCRA hazardous waste manage-
ment facility if a release of a hazardous waste or constituent has occurred, these requirements are in
effect even though the specific regulations for the implementation of corrective action provisions are
not yet final requirements. . . """IK>*K
/ ^SSScx0' n0t U Can ** demonstrated that sediment contamination results from permitted
(e.g.,NPDES) point source discharges, RCRA corrective action at permitted and interim status
hazardous waste facilities may be applicable. Appropriate actions may include investigating the extent
of contamination and carrying out interim and long-term corrective measures.
Refuse Act of 1899
This Act has not, to date, been used in cases involving contaminated sediment cleanup but it includes
provisions which may apply. The Refuse Act is enforceable by the COE but could be enforced in
conjunction with EPA. Under the Act, parties responsible for introducing "refuse" into navigable waters
which obstruct navigation can be compelled to remove the obstruction or pay penalties. Where sediment
contamination interferes with navigational dredging activities, parties responsible for the contamination
could potentially be compelled to remove the contaminated sediments.
Remediation Options
There are three major remediation options: no action, treatment in-place and removal (see
l?tK%£ ' thCre * 3 mUCh greater body of toowN8e concerning removal of sediments because
or the COE navigational dredging program.
Some demonstrations of alternative dredging and disposal methods for highly contaminated sedi-
ments have been done at the New Bedford Harbor, Massachusetts Superfund site. A number of
different dredges were evaluated and CDF and CAD disposal were also tested (USACOE. 1990).
To date, treatment of contaminated sediment before disposal has only been done on a pilot-scale
Although a number of promising technologies exist — some borrowed from wastewater treatment
facilities, some developed to remove or immobilize contaminants in hazardous wastes— the costs
associated with treating large volumes of contaminated sediment are extremely high. Superfund has
been evaluating treatment technologies through its Superfund Innovative Technology Evaluation
(SITE) program, though, to date, this program has focused mainly on soils rather than sediments E P As
Great Lakes National Program Office (GLNPO) is implementing a contaminated sediment treatment
technology demonstration program as part of the Assessment and Remediation of Contaminated
Sediments (ARCS) program mandated by CWA §1 18(c)(3). The IJC Sediment Subcommittee recently
developed a summary on the state-of-the-art in remedial options for contaminated sediments (UC,
• ' '
No Action
Adequate evaluation of the no action alternative to contaminated sediment problems has been
hampered by a lack of evaluation tools such as proven sediment (and associated contaminants) fate and
effects models and risk evaluation protocols for in-place contaminated sediments. The key questions
in evaluating the no action alternative are:
• How soon will conditions improve and how much will they improve? and
• If we don't do anything, will conditions deteriorate further?
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40 Chapter 2
Recent advances in understanding and predicting the fate and effects of in-place contaminated
sediments have occurred as a result of studies of aquatic sites by EPA Superfund (New Bedford Harbor,
Massachusetts), EPA GLNPO (Green Bay, Wisconsin), EPA Office of Research, and Development
(Trenton Channel/Detroit River, Michigan), EPA Region X, the State of Washington (Puget Sound),
and others. ,'.
/ * • ' r • ,
Treatment In-Place
The U.S. has had little experience with treating contaminated sediments in-place. In-place treat-
ment has generally not been considered as an option, although the PCB-contammated sediments in
Waukegan Harbor are to be isolated from the rest of the environment by encapsulating them in-place
using a cofferdam (sheet pile retaining wall) and slurry walls (clay fill to prevent groundwater migration).
There are no criteria or methods currently available that can be used to determine when in-place
treatment is appropriate.
! '
Sediment Removal j
Strategies for evaluating treatment and disposal needs for contaminated dredged material have
been developed by the COE. These were further refined and tested on Puget Sound in the State of
Washington as described below.
Dredged Material Alternative Selection Strategy
The COE developed a Dredged Material Alternative Selection Strategy (DMASS) for Puget Sound
(Cullinane et al., 1986) which includes detailed evaluation procedures for the selection of treatment
and disposal options, as well as the testing and monitoring that would accompany the decision-making
process. While originally developed for Puget Sound, the framework has broader applicability.
The DMASS consists of five phases:
• Presumption of contaminant pathway — Consists of identifying whether the sediments are
contaminated enough to require some restrictions on disposal.
• Confirmation of site-specific contamination — Is an in-depth look at the potential contamina-
tion pathways that could occur from disposal in particular locations.
• Alternative development and screening — Consists of developing alternative ways to eliminate
or minimize the site-specific contamination problems identified in the previous phase.
• Detailed evaluation and ranking — Involves determining ranking criteria and applying them m
a systematic manner to the alternatives developed in the previous phase in order to choose the
most desirable alternatives.
• Alternative selection — Is the final step in which the "best" alternative is selected by whatever
process the decision-makers have agreed to use to reach the final decision.
The procedures established in the DMASS could be very helpful in selecting the appropriate
disposal/treatment alternatives for contaminated sediments when it is decided that sediment removal
is needed. - ,
There are several alternative dredging technologies, each with its own unique ability to deal with
sediments of different types. The selection of the type of dredge to use in a particular situation is
generally dependent on the physical nature of the sediments, the level of sediment consolidation, the
-------
Existing Decision -Making Procedures 41
-* -ne level ot
sediments, such provisions are appropriate, particularly with unco^SS£
Slzes that are not easily resuspended. For contaminated sediments, however, sed me
amuch more significant issue, and the minimization of the environmental thu» o
ediments u ; a primary concern. There are no criteria or methods currently availaWe that
to decide when to use different types of dredging methods.
Treatment of Removed Sediments
an e^rii!n^nrad-f ft6^^^ ^ ** treatmem of sedimen* Amoved from water bodies On
an experimental or pilot basis, various treatment alternatives have been tested to determine whether
Uieir use is appropriate for specific highly contaminated sediments. Although the tecSte "h
^v^oftTt t0 *%****» a?P««i to other contaminated semi-solid or S2£
have not often been used for contaminated sediments, primarily because of their expense
evaluation procedures and strategies developed by the COE and described above could afio£ pcj
££££^^
sediment treatment options for sites on a case-by-case basis. The EPA GLNPO's ARCS Program » ,11
develop guidance on the selection of treatment options based on their studies The IJC ^2^
Subcommittee's summary of the state-of-the-art in remedial options for comarnirfated ^mT.a
mcludedadu.cussionofsomeoftheconsiderations involved m^ngtrcatn«m^%ClW
With sufficient concern about the environmental effects of disposal of highly contammatc J w? •
'" "
t can
c
Disposal of Removed Sediments
the WA^nH&ln^f K^l^0 waters oftheU-S-and °cean waters are regulated under
1030 MPRSA, respectively. In general, the CWA §404(b)(l)
the WAnH&n K -- un
h ,?h H- §,1030^ MPRSA, respectively. In general, the CWA §404(b)(l) guideli
that the chsppsal of dredged material must not result in significant degradation rf the ai,ua
ment, mcludmg human health and welfare considerations, while MPRSA requires that the
,
m ^""^"00 the COE has developed a series
1 ?? f m ^"J"^"00 ^* the COE has developed a series ofpr
ont to heaa±; KST^KdT5n-making- In the CaSC °f ^n dumping, J^RSA protoc^is
only to the acceptabihty of the dredged material for disposal in the ocean. In addition, RCRA and
tphrr^^and tt^ptions for dredged "dta-* - expiained in •«->*- foi1
rive? ^^ t0 ^ dufaP^
nvers, the Great Lakes, and other rivers and lakes) are regulated entirely under the CWA. Outside «i
be -
.
en ^bey0ndI3 M«ti«»-inaei from the baseline) only MPRSA applies. Within the
temtonal sea (0 to 3 nautical miles seaward of the baseline), there is some overlap between CWA and
m*,? M In. geneiaj' ^^ this re8ion' CWA regulates fill material (which may include dredged
matena discharged for the purpose of fill, such as beach nourishment) while MPRSA regulates dred ecd
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42 Chapter 2
Two international agreements are considered here as well. Both the GLWQA and the London
Dumping Convention (LDC) contain provisions relating to disposal of dredged material. Dredging and
disposal guidelines have been developed by the IJC Dredging Subcommittee as called for in Annex 7
of the GLWQA (IJC, 1982).
Draft EPA/COE Dredged Material Disposal Strategy
The framework for evaluating dredged material disposal options utilized by the EP A OMEP, Office
of Wetlands Protection (OWP), and COE is outlined in the draft Dredged Material Disposal Strategy
Document (USEPA. 1990c). The strategy combines the considerations of both MPRSA and CWA on
the disposal of dredged material into a single framework. The document also provides a discussion of
the factors that need to be considered in various aquatic disposal environments (e.g., estuaries,
continental shelf, rivers, lakes, etc.), and upland disposal environments. As required under CWA §404,
these factors include biological-chemical, and physical impacts of the dredged material on the aquatic
environment. •
Marine Protection, Research, and Sanctuaries Act,
MPRSA gives EPA the authority to designate acceptable dumpsites for the disjposal of dredged
material in the territorial waters of the U.S. The COE is given the authority to issue ocean dumping
permits where it is determined that "such dumping will not unreasonably degrade or endanger human
health, welfare, or amenities or the marine environment, ecological systems, or economic poten-
tialities." §§102(a)(B) through 102(a)(D) require the consideration of human health and ecological
effects in creating permitting criteria. All material considered for dumping must meet the criteria set
forth in Ocean Dumping Regulations (40 CFR Parts 220-228) or a waiver of the criteria must be
requested.
§103 of MPRSA specifies that all proposed operations involving the transportation and dumping
of dredged material into ocean waters must be evaluated to determine the potential environmental
impact of the dumping. In addition, EPA requires that the ocean dumping of dredged material be done
at EPA-designated dump sites. Sites that have not yet been formally designated have been given an
interim designation until Environmental Impact Statements (EIS) can be prepared for their designa-
tion.
In the formal dump site designation process, acceptable sites are chosen using a screening technique
that selects a zone of siting feasibility (a distance from the dredging site within which it is feasible to
transport dredged material), then eliminates from this zone hard bottom areas, areas of significant or
unique habitat, habitats of endangered species, and areas of historical value, among others. Once these
areas have been eliminated, potential dump sites are selected.
Potential sites are then surveyed to determine the characteristics of the bottom sediments, the
nature of the biota of the site, and the general nature of water column and near-bottom currents. The
site nearest the dredging site that would result in acceptable adverse impacts caused by the dumping is
designated. This evaluation process is formalized in an EIS for dredged material dump site designation.
A complete assessment process for determining the suitability of dredged materials for dumping in
ocean waters has been developed jointly by EPA and COE and is explained in the document Draft
Ecological Evaluation of Proposed Discharges of 'Dredged Material into Ocean Waters (the "Green Book")
(USEPA, 1990b). This assessment strategy was described earlier in the section of this chapter on
assessment options.
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Existing Decision-Making Procedures 43
Clean Water Act
£^^"£,2?^^^°!*^- ™<-a* into CWA §<04 wa.ers is under
n H eHman,Ual 'f J0"0* thC tierCd tCSting frameW°rk °f the Green Bo Aso evera o
^have developed their own testing protocols under the §404(b)(l) guidelines and adanta
***• DMfli °f ^ ' "
the
options.
Resource Conservation and Recovery Act and Toxic Substances Control Act
HiJ^lfS I5?tA ^ 7^ thCre 3re restrictions P'aced on the options that can be used for the
dKposal of dredged material. Under RCRA, any characteristic hazardous waste (a waste that has one
R^".±S mtS^0" ?' R,CRA-Prescribed testing methods) must be disposed of by
RCRA-approved methods. Contaminated sediments may be toxic under the toxicitv character Itl
leaching procedure (TCLP) test, a test that compares the concentrations of^l^Tn^
teacha* from the dredged material with levels established to protect human health and t£ Tendon!
men When a leachate concentration exceeds the established level, then the dredged material exh bks
he toxicity charactenstic," and generally must be managed in a RCRA-permitted or interim statu*
focihty (a Subtitle C Hazardous Waste Landfill or equivalent) and must conform to treatment s'nda d
conning of a specified level of hazardous constituent or specific treatment technology It should be
noted that the COE's position is that dredged material is not subject to RCRA SuKmenu COE
maintains that dredged material is not a solid waste; EPA maintains that dredged materiaU a Sid
waste under RCRA, but as part of its Sediment Strategy (see Chapter 4), EPA S soHch pub ic
comments on the appropriate statutory and regulatory framework for managing dredged sediment'
^RC^^douswasteprogramhasastatutorydirectivetoprohibitlanddisposalofuntreated
nf^&T "f ** *?°£ S?uCified datCS f°r Particu'arwastes. This prohibition; authorized undeS"
hL ^ ^OWn "->? ^ * thC SpCCified dates for most haza^ous wastes have passed EPA
has prohibited or restricted most hazardous wastes from land disposal without treatment '
COE Management Strategy
A predecessor to the MPRSA guidance discussed above was the COEstrategy for selecting disposal
options for dredged matenal and the accompanying testing required (Francinfues et a"^ Tj
COE strategy is summarized in Figure 8.
IJC Dredging Guidelines
f. ^ ?"?*?** S"**0™*"** of ^ IJC Water Quality Board published an evaluation procedure
for selecting disposal options for Great Lakes dredging projects in response to the GLWQA .Annex 7
requirement for the development of compatible evaluation guidelines. The basic procedure (Figure 9 ,
rieSd^5^ T^f0r?V a^°n °fCrea< Lakes Dredging Projects (IJC, 1982), is similar to the
tiered protocol developed under MPRSA for ocean disposal.
London Dumping Convention
The Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter
more commonly known as the London Dumping Convention (LDC), was signed in 1972 and entered
into force in 1975. The conventions of the treaty affect all dumping seaward of the baseline of the
territorial sea and include specific limitations and bans on the dumping of certain substances within its
several annexes. The Ocean Dumping Guidelines and the testing protocols within the Green Book
implement the goals of the LDC within U.S. coastal waters
-------
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-------
Historical information and
ecological evaluation
No
contamination
Sediment
physical characterization
Possible contamination
Sediment chemistry
•Bulk chemical
characterization
•Elutriate
Contaminants present
Sediment bioassessment
•Acute toxictty^~~
•Bioaccumulation
•Reproductive impairment
Evaluation of dredged
material disposal options
Y
Severe
contamination
identified
Dred9jn9 .^J«ct Evaluation Framework
-------
46 Chapter 2
Annex 1 prohibits entirely the dumping of extremely hazardous substances such as organohalogen
compounds, cadmium, mercury, oil. plastics, and high-level radioactive wastes. The dumping of dredged
material which contains these substances is forbidden if they are present in "other tham trace amounts."
Annex 2 includes somewhat less hazardous substances such,as pesticides, cyanides, zinc, arsenic, lead,
copper and organosilicon compounds. The dumping of Annex 2 substances may be conducted only
under a special permit. Pursuant to Annex 3, the dumping of all other substances requires permits issued
by the appropriate nation after consideration of factors that are set forth within the Annex.
-------
Chapter |3
Comparison of Existing
Decision-Making Procedures for
Contaminated Sediment Management
Tn this chapter, the existing programs and procedures that were described in Chapter 2 are compared
JLto identify gaps and inconsistencies in the current decision-making process for managing con-
taminated sediments. Some areas, such as dredged material testing for open-water disposal have
' de^lon Protocols which are in a fairly advanced state. However, other areas, like assessment of the
need to take remedial action on in-place contaminated sediments, are ai a less developed staee and are
only now beginning to be addressed. *
The following sections overview the decision frameworks from Chapter 2 and identify programmatic
gaps and inconsistencies. The order followed is the same as that followed in the previous chapters.
Finding Contaminated Sediments
Finding contaminated sediments can involve reviewing existing data to decide whether there mav
be a reason to suspect contaminated sediment problems or actually conducting monitoring surveys to
produce the necessary data. If problems are suspected, then one would advance to the next stage in the
process — assessment. Table I summarizes how existing programs assist in finding contaminated
sediments. ,
Although there is a great deal of monitoring data available from surveillance and monitoring
programs under the CWA, to date these programs have been focused on effluent and water quality
rather than sediment quality issues (excepting §404 dredge and fill activities). As a result, both Federal
and State monitoring programs sample sediments on an irregular basis at best. Even though the effluent
andjvater quality monitoring data can be used to help identify potential sediment contamination
problems (since sediment quality problems usually reflect water quality problems), direct monitoring
01 sediments is desirable. One of the main reasons for this is that many of the chemicals that are of the
most concern for sediment and wildlife contamination have such low partitioning into water that thev
are often not detected in water analyses, whereas they are detectable in sediment analyses. '
Some sediment monitoring is now accomplished on the State and Regional level in conjunction
with special programs (e.g., the Chesapeake Bay Program, the Great Lakes National Program Office.
PSDDA) arid as part of expanded State monitoring programs (e.g., the State of Washington and New
X *Jl Iv !• • • ,
The surveillance and monitoring programs called for under the GLWQA are to include sediment'.
monitoring. However, because the actual monitoring is done by the Federal, State and Provincial
agencies who do not routinely undertake sediment monitoring, this component is often neglected. .The
'.'..'•'•• '.'.'' 47 .
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18 Chapter 3
Table 1. Finding Contaminated Sediments.
Program or Statute
Clean Water Act
Comments
§115
NPOES and water quality monitorinfl
§404 dredge nnd fill activities
Great Lakes Water Quality Agreement
Marine Protection, Research and
Sanctuaries Act
Requires EPA to identify "In-plaee pol-
lutants". Program currently not funded.
Primarily oriented toward effluent and
water quality monitoring. Sediment
monitoring not routinely done.
Regions and most States monitor on a
case-by-case basis when other evidence
(i.e., fish contamination levels) indicates
possible problem.
Several Status adopting intensive basin
surveys which include regular sediment
sampling
Navigational dredging project evalua-
tions and permitting collect significant
volumes of informatton on sediment
quality but information is not readily ac-
cessible for other purposes such as en*/.
acterization of sedinwnt contamination
and must be retrieved manually.
Monitoring data is biased - typically
only available from nnvigatonal cnanne*
ledimems or from disposal sites,
Sediment monitoring an integral pan of surveillance and monitoring plans but
reliance on ongoing monitoring programs by the Parties mean» sudiment com-
ponents of monitoring often get last priority.
Remedial Action Plan development process hx Areas of Concern can recu.re **-.
pling.
Chesapeake Bay Program
Great Lakes National Program Office
§201 establishes monitoring requirement for designated dumpinffl trtes OMEP u»ee
a tiered approach for establishing site monitoring n*eos Sites nn>
monitored annually.
6202 requiremant for monitoring impact of all poJIutamt.
Sediments intensively sampled for toxics and nutrients.
Puget Sound Drudged Disposal Analysis
and Puget Sound Estuary Program
Ongoing sediment monitoring program for Great Lakes rivers and harbors Don in-
side and outside of navigation channels.
PSDDA monitoring focuses on disposal sites. •
PSEP monitoring focuses on areas outside of dumpsitea and navigation channels
Resource Conservation and Recovery Act
Interim status facilities and permittees or facilities creating an "imminent and sub-
stantial endangerment" from past releases may be required to sample sediments.
Comprehensive Environmental
Response, Compensation, and Liability
Act
States and Regions identify sites with possible contamination prohloms for possible
inclusion on the NPL. •
Remedial Action Plan process for the Great Lakes AOCs is heightening awareness of the importance
of including sediments in surveillance and monitoring programs. As a result sediment monitoring is
being incorporated into the monitoring plans for the AOCs.
Regular monitoring is performed in Puget Sound as part of PSDDA and PSEP in navigation
channels, around dumpsites, and in other parts of the estuary. A database is being developed which will
include this information as well as data from Superfund sites in the area.
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49
_____
The CWA and MPRSA programs for the permitting of aquatic disposal projects collect large
amounts of data from project proponents which could be used to identify potent contam na ed
sediment problems. However, for the most part, this data is not in a readily accessible form for use
outside the onginating program. Much of the monitoring data from these programs is only° v" lt,e n
hard-copy form which makes searching for. retrieving and using the information difficult. In addition
£ese programs are not deigned to provide an overall sediment quality characterization of an area
because they usually only sample wuhm the navigational dredging project areas.
1 P^6,!"16!*!^ contaminated sediment monitoring data for some locations, but it
The current state of monitoring activities with regard to sediments indicates that, as a general rule
sampling is performed only as'part of special studies where existing evidence indicates a probable
contamination problem The most common trigger for special sediment studies (as stated by the various
Regions) is elevated fish tissue concentrations of contaminants.
While this approach does provide for a channeling of resources into the most egregiously con-
taminated areas, it does not provide for the development of a database on background levels and general
trends m contamination. Developing contamination problems may not be discovered until levels
become high enough to cause adverse environmental effects. There is also not a single set of criteria
which are used to determine when special studies should take place.
Assessment of Contamination
The significance of the deleterious effects of in-place contaminated sediments has only been
h^fT^ rCQen, y> r ^ *** °f det^rminin8 ^P0531 ^ions for dredged material has a long
tustory. As a result, the ^assessment protocols that have been developed to date have focused primarily
on the issue of what the disposal options are once sediments are removed from a water body It is
becoming increasingly apparent that there are situations where something will have to be done to
mitigate the negative impacts of contaminated sediments, possibly including removal, even though
dredging is not needed for any other purpose. What is needed in this case is an assessment protocol
that determines the environmental impacts and risks from the in-place contaminated sediments The
existing program that currently performs this kind of assessment best is CERCLA (Table 2) In the case
of aquatic Superfund sites, a very comprehensive risk assessment is typically performed including
sediment/water/biota/human interactions. . .' f *
Tlie IJC Sediment Subcommittee's assessment protocol (IJC, 1988a) provides a comprehensive
tiered assessment program for m-place contaminated sediments. The U.S. and Canadian Federal
%enS?Ar^?°^!e/SS2e Gfeat UkeS are evaluatini th« usefulness of the IJC assessment protocol.
The EPA GLNPO ARCS program called for by CWA §1 18(c)(3) is developing a standard sediment
assessment protocol, using the IJC protocol as the starting point. The ARCS program is performing
simultaneous testing of sediments with a wide variety of chemical and biological tests with the aim of
eventually reducing the number of tests to those that provide the needed information in the most
resource-effective manner. Therefore, proven cost-effective contaminated sediment assessment
protocols for freshwater should become available in the near future.
The Puget Sound program has developed comprehensive sediment assessment protocols for
m-place contaminated marine sediments in that area. Many of the principles from that program can be
applied to other marine sites.
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50 Chapter 3
Table 2. Assessment of Contamination.
Applicable Existing Programs
Comprehensive Environmental Response, Compensation and
liability Act
Puget Sound Program
Clean Water Act
Marine Protection, Research, and Sanctuaries Act
Chesapeake Bay Program
Great Lakes National Program Office ARCS Program
Office of Emergency and Remedial Response asseases sites
as -part of RI/FS process for aquatic sites. .iVssessments are
often very comprehensive and include infturmatJon to allow
risk assessments to human health and th« environment from
no action and various remedial action alternatives.
Sediments assessed relative to site-specific ARARs. ARARs set
based on possible receptors and exposure routes and avail-
able criteria/standards.
Includes a comprehensive sediment assessment program.
Sediments assessed relative to region-specific AET-based and
EqP-based criteria. State of Washington promulgating sedi-
ment management standards.
EPA mandated to develop environmentally protective criteria:
Currently working toward establishing sediment quality criteria
and assessment protocols.
Assessment protocols under development to serve function of
a Green Book for $404 waters.
404(b)(1) guidelines offer general guidance on dredged
material testing. Several Regions have davuloped local §4O4
guidance.
§103 guidance developed for the evaluation of dredged
materials for ocean disposal. Various Region* have specific
testing protocols for use within tills guidtmeo.
Planning implementation of sediment triad strategy for bay-
wide assessment of sediment contaminatfom.
Developing sediment assessment tests and protocols starting
from the UC Sediment Subcommittee assessment protocols
Currently, the application of sediment assessment strategies to sediments which are not being
removed as part of dredge and fill activities is, at best, inconsistent. While EPA headquarters is now
involved in the development of numerical sediment criteria and standardized bioassays, there is no
existing continuity in sediment assessment.
The Office of Emergency and Remedial Response, under CERCLA, has performed a number of
sediment assessments. These have involved application of various methods for setting ARARs for
sediments (including the application of equilibrium partitioning approach-based criteria)! Consistent
sediment quality criteria would lend continuity to the Superfund program.
In different sections of the country, a number of sediment assessment methods and strategies have
been applied. In Puget Sound and the West Coast, AET criteria have been applied. Within the Great
Lakes, a reference approach has been traditionally applied which has evolved to include bioassays ais
well. A broad strategy using an expanded "triad" approach has been recommended. Several States have
begun development of sediment quality criteria and standards. The State of Washington is in the process
of implementing sediment management standards that include sediment quality criteria.
Implementation of national sediment quality criteria should be accompanied by a consistent
assessment strategy within which the sediment quality criteria would be used.
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Comparison of Decision-Making Procedures... 5J
Prevention and Source Controls
Table 3 summarizes the existing control programs that can be used to prevent or control sediment
contamination.
The existing program that is most likely to be used in preventing and controlling sediment
contamination is the CWA point source control program and the nonpoint source programs which are
under development. However, no known NPDES permit limits have been written to date which directly
protect sediment quality. There is no guidance on the use of sediment quality criteria or other
assessment methods in the development of point source permits.
Table 3. Prevention and Source Controls
Applicable Existing Program*
Clean Water Act
Toxic Substance* Control Act
Comprehensive Environmental Response, Compensation and
Liability Act
Type* of Controls Possible
Point source discharge controls through NPDES permitting
program. No known permit limits written which directfy protect
sediment quality within Regions or States.
Nonpoint source discharge controls through nonpoint source
management programs. May be controlled by setting TMDLs
Prohibition or limiting of production or distribution of harmful
substances nation-wide. No known prohibitions based upon
Office of Pesticide Programs uses a four step assessment pro-
cedure to decide whether to place restrictions on uses and dis-
posal Of bioeidW. Soecial aiuntmant* hnua K*an KI..H nn
Establishment and enforcement of air quality standards and
new source emission standards for toxics. Not known to nav«
Whatever remedial action is justified based oh risk analysis
and cost/risk reduction analysis. .
In order to effectively incorporate sediment quality considerations into point source permitting
decisions, two tools are needed: sediment quality criteria and WLA models that incorporate sediment
and associated contaminant fate and transport Vfuch progress is being made in both these areas through
the research efforts of the EPA Office of Water, Office of.Research and Development, Superfund and
the GLNPO. Currently, nearly all States have developed EPA approved assessment reports and
management programs for, nonpoint source pollution under CWA §319. However, States have not
typically addressed the contaminated sediment issue in their nonpoint programs. This is possibly due to
the paucity of information available on the extent of in-place pollutants in some States and competing
State priorities that need to be addressed with §319 funds. While no remediation of sediments has
occurred under this program, some of the funded projects will result in prevention of further sediment
contamination.
Programs other than CWA are less likely to be used for control of contaminated sediment problems
because contaminated sediments do not fall within their jurisdictions as readily and those programs do
not have the resources that would be needed to expand their scope to include sediment issues on a
routine basis. On the other hand, in the isolated cases when these programs do become engaged in
contaminated sediment issues, they have some of the most powerful tools in existence for prevention
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52 Chapter 3
and remediation (e.g.. the power to ban chemicals or to carry out or enforce cleanups). A strategy needs
to be developed for the judicious application of these other, programs in those cases where the problem
is severe and where CWA authorities are not sufficient to address it.
The revised version of the CERCLA HRS gives increased attention to contaminated sediment
issues, which will increase its usefulness for identifying in-place contaminated sediment sites. However,
given the numbers of other sites competing for cleanup resources, aquatic sites may not get high priority.
Under CWA, CERGLA, and the Refuse Act of 1899, dischargers who can be shown to be directly
responsible for sediment contamination problems can be compelled to remove and/or remediate
contaminated sediments. Enforcement actions have been taken on this basis (e.g., Waukegan Harbor,
New Bedford Harbor, Black River, Grand Calumet River). Enforcement actions can be difficult since
the sources of sediment contamination are, more often than not, difficult to tie to individual dischargers,
especially in harbors with multiple dischargers. There is no current guidance on conducting enforcement
actions using sediment contamination as a tool to compel dischargers to clean up. "
Remediation
As summarized in Table 4, CERCLA has a systematic process of developing and evaluating
remediation alternatives for in-place contaminated sediment situations. Although there are no specific
protocols for evaluating sediment contamination problems per se, the nature of the RI/FS process is
such that a very thorough examination of remedial alternatives is performed. In addition, the CERCLA
program has resources to do needed laboratory and pilot-scale studies of promising remedial tech-
table 4. Remediation
Applicable Existing Program*
Comments
Comprehensive Environmental Response, Compensation and
Liability Act
RI/FS process systematically evaluates atoiimative remedial op-
tions based upon a variety of factors including degree of.
protection, permanence, costs, adverse impacts to the environ-
ment, etc. Guidance for remediation of all media, including
sediments, follows consistent framework ttiat has an orienta-
tion toward the entire site.
Laboratory and pilot-scale studios of remedial alternatives un-
dertaken as needed.
Various remediation strategies employed including remove!
and capping.
Clean Water Act
No national guidance on when or how to raimedlate.
Great Lakes National Program Office ARCS program develop-
ing guidance on selecting remedial actionn and conducting
laboratory and pilot-scale studies on promising remedial alter-
natives.
Dredged material testing protocols developed for §404 evalua-
tions could be used to assess feasibility of remedial alterna-
tives involving removal of sediments. '
Marine Protection, Research and Sanctuaries Act
Dredged material testing protocols deveto^ned for MPRSA
evaluations could be used to assess feasibility of remedial al-
ternatives involving removal of sedimento.
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Comparison of Decision-Makine Procedures...
nologies in order to arrive at the best alternative. Remediation activities at aquatic Superfund sites like
New Bedford Harbor, Massachusetts will provide a model for such activities elsewhere
Outside of QERCLA, there is no guidance on when remediation should take place or on how
remediation options should be chosen. This gap will be partially filled by the implementation of sediment
quality criteria. Criteria can provide a "yardstick" for determining when sediments need to Z
remediated.
niln^ P T H f ° r°gram °ffiCe ^^ Pr°gram » ""^ out a series of laboratory- and
^lot-scale studies of promising remedial alternatives for contaminated sediments. The knowledge
gamed m these studies will be combined with results of other efforts including those of Superfund ?o
produce a guidance document on remedial alternative selection for contaminated sediments
DMA ^nnA ' Pr°Veh CxiStinS Pr0t0cols such » the G^en Book.
s^Lo ^ H the1UPCOmm« I404 Testin8 Man"*l for freshwater can be used effectively to
select dredging and disposal options and any accompanying control measures that may be necessary.
Treatment of Removed Sediments
Treatment options for contaminated sediments are currently chosen on a case-by-case basis This
is. true under all applicable programs and regulations. Currently, little information is available On the
practicability of various treatment options for contaminated sediments. The state of knowledge for
sediment treatment lags behind that for the treatment of soils. §
th, ™C I* KT^Tf nd SITE 3IKl °reat UkeS Nad°nal Pr°«ram Office A*05 Pr°i™™ are testing
the prac icabdity of vanous treatment options for contaminated sediments and may be providing
information thatcan be used to aid in the selection of treatment options. Most of the" o* fo£ o £
ested are methods created for the treatment of soils. Few treatment methods have been created
specifically for sediment treatment, ^caitu
Disposal of Removed Sediments
f°r !hC diSP°SaI °f rem°Ved sediments « readily .available from the
material regulatory programs.
In MPRSA §103 waters, testing protocols are well developed. The Green Book provides national
guidance on dredged material testing for ocean disposal. Based on the national guidance, several
Regions (i.e., Regions I, H, DCand X) have developed Region-specific protocols on the type of analvt ,cal
procedures to be applied in this testing. •
Testing protocols under CWA §404 are more highly variable across the Regions. No national
guidance has been issued to date. However, the Office of Wetlands Protection is cooperating with COE
on the development of aGreen Book-equivalent for §404 waters. Several of the Regions, in cooperation
with their respective COE counterparts, have developed and are implementing their own guidance for
S4U4 waters (i e., Region I and X), while others have produced interim guidance (i.e., Region V) which
« still :not fully implemented. These guidances are variable in their scope, ranging from basic bulk
chemical testing to detailed, tiered biological/chemical testing and in situ biota evaluations.
^ The LTC Guidelines and Register for Evaluation of Great Lakes Dredging Projects (IJC, 1982)
developed under the GLWQA, contains a tiered protocol employing physical, chemical and biological
testing. Although this protocol is not formally being used by EPA, elements of it appear in testing
protocols such as the Region V testing strategy for navigational dredging projects.
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54 Chapter 3
Figure 5. Disposal of Removed Sediments
AppUcabte Existing Programs
TeeUng Proteeoto
Marine Protection, Research and Sanctuaries Act
Well-defined tasting protocol* establishiid and under revision.
Includes tiarad biologicaJ/chamical testing protocol. '•
Guidance for the designation of disposal' sites based upon en-
vironmental and human health effects and possible beneficial
use impairments. Calls for disposal sito cnonitoring.
Region-specific guidance developed or in progress within
Regions I, II, VI, IX and X
Clean* Water Act §404
Office of Wetlands Protection developing dredged material dis-
posal tasting protocols for §404 waters. Mo national protocols
in use.
Impacts on disposal sit* evaluated under requirements of
CWA§404(b)(l) guidelines.
Specific testing requirements developed within Regions I. V
and X (not fully implemented in Region V). Tests range from
minimal to very detailed, from basic bulk chemistry to
detailed, tiered biological/chemical testing and In situ biota
evaluations. "
Parts of EPA Region V GuMvtlne* for IN) Poilutional Clas-
sification of Great Lakea Harbor Sediments also used by
the other Great Lakes Regions (Regions II and III).
Great Lakes Water Quality Agreement
Tiered assessment protocol in UC Guidelines for Evaluation
of Great Lake* Dredging Prefaets includes physical, chemi-
cal and biological testing. Parts of the protocol are used by
the Great Lakes Regions (II, III, and V).
There is a possibility that guidance for dredged material disposal may differ som
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Chapter 4
Future Directions:
The EPA Sediment Strategy
r|Tie first three, chapters of this document have concentrated on the state of decision-making
A regarding contaminated sediments as it currently exists within EPA. The final chapter examines
future directions in decision-making with special emphasis on the sediment management strategy being
developed by EPA to coordinate sediment-related activities Agency-wide.
The Sediment Strategy
In 1989, the Office of Water organized a Sediment Steering Committee chaired by the .Assistant
Administrator for Water and composed of the Deputy Assistant Administrators of all the offices
involved in sediment-related activities and the Deputy Regional Administrators for EP A's ten Regional
Offices. On January 17, 1990, the Committee decided to prepare an Agency-wide sediment manage
ment strategy to coordinate and focus the Agency's resources on sediment problems. The goals of the
strategy are to eliminate ongoing contamination of bottom sediments, to reduce existing comaminanor.
as much as possible, and to reduce or eliminate other adverse effects that sediments may cause TV
objectives of the strategy include: '
• Promoting consistent, environmentally protective decision-making across EPA offices R.; -\
and States, taking into account technical and economic feasibility,
« Explaining differences indecision-making with respect to sediments among EPA program .«t <\ «
« Promoting coordination of EPA and State research, technical, and field activities.
• Defining relationships between EPA and the States where EPA seeks new statutory author ;v;
or seeks to use authorities that it has not implemented,
• Describing the extent and severity of contaminated sediments,
• Focusing public attention on the problem, and
• Focusing Federal, State, and private resources on the problem.
To study the technical and regulatory issues related to these objectives, four workgroups were
formed in February 1990. The workgroups are staffed by 80 members taken from Office of Water.
Office of Solid Waste and Emergency Response; Office of Pesticides and Toxic Substances; Office oi
Research and Development; Office of Policy. Planning and Evaluation; Office of General Counsel.
Office of Enforcement; Office of Federal Activities; and each of the Regions. In August 1990. the
workgroups completed draft options papers on how to 'improve the Agency's efforts to assess, prevent
remediate, and manage the disposal of contaminated sediment. Most of the papers concentrate on ho*
55
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56 Chapter 4
to use existing authorities better, but options for remediation and nonpoint source issues also look at
statutory changes that could be implemented in reauthorization of an existing law or in passage of new
legislation. The Deputy Assistant Administrators of the offices working on the strategy were briefed
on the options papers in September and October 1990.
Major Issues
The four workgroups have focused on resolving 13 major issues. Workgroup members identified
options for responding to each of the issues and are presenting these options to the Steering Committee
for consideration. The major issues are:
1. National Inventory of Contaminated Sites and of Facilities that Contaminate Sediments
2. Ranking Sites and Facilities on an Inventory List for Further Action
3. Consistent, Tiered Testing Approach to Assessment of Sediment Quality
4. Point Source Control
5. Nonpoint Source Control ;
6. Revising Pesticide Registration Assessment Procedures
7. Revising Toxic Chemical Registration Assessment Procedures
8. Roles and Responsibilities for Remediation
9. Identification of Sediments needing Remediation
10. Identification of Sediment Remediation Goals
11. Enforcement-Based Authority to Require Remediation
12. Managing Dredged Material -
13. Applicability of RCRA to Dredged Material Disposal.
Once the Steering Committee has approved the range of options offered for each major issue. EPA
will consult with other Federal agencies and representatives of ten State governments selected from
across the Regions. The Federal agencies included in the-consultation will be the U.S. Geological
Survey, National Oceanic and Atmospheric Administration, the Army Corps of Engineers and the
Department of the Interior's Fish and Wildlife Service, among others. For the State consultations, each
of EPA's ten Regional Offices will select one State government representative who is> very familiar with
contaminated sediment issues in that Region. The views of these government officials will be presented
to the Steering Committee when they make a preliminary selection of the options in April 1991. The
preferred options will then be discussed with environmental and public interest g[roups before the
Steering Committee makes a final decision on the options. After continued consultation with the Office
of Management and Budget (OMB) and the Federal agencies, EPA plans to have a draft sediment
management strategy ready for publication in the Federal Register by the end of 19911
Cross-Program Issues
Three issues related to contaminated sediments have been identified as cross.-program issues. These
are:
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Future Directions: The EPA Sediment Sirate
National Inventory of Sites and Sources
To date, no agency has completed a comprehensive, national inventory of sites with contaminated
sediments or of facilities causing sediment contamination. Existing sediment data have been compiled
to some degree, but the. use of varying sampling and analytical methods make it difficult to compare
sues across the country or even within States or Regions. Most data on sediment quality are currently
drawn from anecdotal studies conducted by various State and Federal offices.
_ A comprehensive sediment inventory of sites and sources could aid decision-makers in managing
he alocat,on of resources toward actmties with the greatest potential for environmental benefit A!
inventory could have utihty for deosion-making in several aspects of sediment management, including
• Finding contaminated sediments - Monitoring and surveillance programs could be focused on
those areas where contamination is suspected and where little or no information on sediments is
clVclllHDiC. , ,
. * P5f e°t\onandMurrerontrok-An^^
of facilities responsible for sediment contamination so that permit limits could be written with
sediment quality as a consideration.
• Remediation - Contaminated sites could be compared and remediation priorities could be
determined.
Consistent Testing Protocols
As discussed earlier in this report in the sections on assessment of contaminated sediments most
programs do not currently utilize a single set of biological and chemical testing protocols for the
assessment of contaminated sediments. The major exception to this rule is the MPRSA §103 ocean
dumping program which uses an established tiered testing strategy.
Adopting a consistent tiered testing methodology would encourage consistency in data generation
which would, in turn, provide a uniform basis for Agency decisions regarding the regulation and
remediauon of contaminated sediments. The primary disadvantage of adopting such a methodology
would be the difficulty in defining a consistent methodology that simultaneously meets the needs and
falls within the regulatory mandate of prevention, remediation, and dredged material disposal programs.
Enforcement-Based Remediation
EPA recognizes that a number of sites with contaminated sediments pose a significant risk to public
health or the environment and warrant remediation. A variety of EPA's statutory authorities include
enforcement. provisions that may be used to:
• Compel parties to clean up the sites they have contaminated,
• Recover costs from responsible parties for EPA-performed cleanups, and/or
• Coordinate with natural resource trustees to seek restitution of natural resource damages.
r Pru?f tljt5esolutionof this ^"e involves determining whether EPA should use existing authorities
(i.e., CWA, CERCLA, RCRA, etc.) or if new authorities are needed (in the form of new legislation)
to deal adequately with sediment-related enforcement issues.
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58 Chapter 4
Potential Impact of the Management
Strategy
As discussed previously in Chapters 2 and 3, numerous gaps and inconsistencies currently exist with
regard to the management of contaminated sediments across EPA regulatory programs, offices,
Regions and States. Clearly, a coherent Agency-wide strategy could resolve numerous issues related to
contaminated sediment management.
The following discussion looks at the potential impact of a comprehensive strategy on the individual
program offices in EPA. ,
Finding Contaminated Sediments
The proposed national inventory of sites and sources, and subsequent ranking in terms of environ-
mental and human health impacts (Issues 1 and 2, ^bcve), could provide a valuable resource for the
identification of sites with sediment problems and the allocation of resources toward the highest-risk
sites. Existing monitoring and surveillance programs could use the inventory to direct their resources
to focus on sites for which additional monitoring information is needed. Listings of sources could also
be used to guide monitoring programs toward possible contamination problems.
Assessment of Contaminated Sediments
Consistent, scientifically sound protocols need to be developed to assess the impacts of con-
taminated sediments on human health and the environment There is real need for sediment assessment
tools outside of those programs not related to dredged material disposal. The identification of this issue
as a cross-program one indicates this. Work toward establishing sediment quality criteria for the
protection of aquatic life now underway within the Agency should provide an important tool. However.
criteria are only one assessment tool which needs to be implemented as part of a; total assessment
protocol. The creation of a consistent tiered testing scheme (Issue 3, above) for sediment assessment
could help to fill this gap. The difficulty in the creation of such a scheme is accounting for the varied
needs of different programs (i.e., CERCLA vs. dredge and fill vs. NPDES). These issues are being
addressed by the Steering Committee.
Prevention and Source Controls
Four of the thirteen major issues listed above directly address prevention (Issues 4, 5, 6, and 7.
above). Extensive discussion is taking place on the control of point and nonpoint sources that are
responsible for sediment contamination. To date, no NPDES permits have been written which explicitly
consider sediment contamination as an endpoint in establishing permit limits. Nonpoint source control
programs are just becoming established in many States. Sedimentation problems are aiddressed in these
programs; however, few programs direct resources toward controlling nonpoint sources of sediment
contamination.
v
The Office of Pesticide Programs (OPP) is considering incorporating sediment testing into their
assessment of whether or not a new or existing pesticide should be banned or restricted in its use. The
Office of Toxic Substances (OTS) is considering the same approach for their reviews of new and existing
chemicals and has begun development of three testing protocols. , . - .
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Future Directions; The EPA Sediment Smuegy 59
Remediation
Remediation issues may also be given high priority in the strategy (Issues 8, 9, 10, and 11). The
Office of Emergency and Remedial Response (OERR), Office of Solid Waste (OSW), and Office of
Water (OW) are considering options for remediating contaminated sediments. Enforcement is addi-
tionally identified as one of the cross-program issues. There are a number of legal actions under a variety
of authorities underway by the Agency to compel responsible dischargers to remediate contaminated
sediments.
Treatment of Removed Sediments *
To date, sediment treatment options are not directly being considered as part of any one of the
major issues covered within the strategy. The state of knowledge regarding treatment options for
contaminated sediments is poor. Several programs, including the Superfund SITE program and the
Great Lakes National Program Office ARCS program, are currently testing treatment technologies on
a pilot scale to determine feasible options.
Disposal of Removed Sediments
, Dredged material disposal is the most advanced of the sediment management categories with regard
to the availability of detailed guidance and developed testing protocols. CWA §404 and MPRS A § 103
programs utilize extensive guidance issued on both national and Regional scales. Some issues remain
unresolved, such as the applicability of RCRA to dredged material and the role of economics in the
evaluation of dredged material disposal. These issues are being addressed within the strategy (Issues
12 and 13, above). .
In summary, the development and implementation of EPA's sediment management strategy will
make significant progress toward addressing the key issues identified in this document.
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References
'• • ' • \
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Subcoraninec.
uaU»' SAB'
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