ASTM E3240-20

Standard Guide for Risk-Based Corrective Action for Contaminated Sediment Sites

SIGNIFICANCE AND USE
4.1 This guide provides a consistent and transparent decision-making process for selecting risk-based corrective actions at sediment sites (that is, a Sediment-RBCA). Sediment-RBCA shares the same process as other RBCAs described in E1739, E2081, and E2205/E2205M but with explicit consideration of the constraints on how the available sediment assessment techniques impact decision making. Several factors exist that distinguish sediment sites from upland sites and warrant unique consideration, including background, potential for recontamination, sediment stability, sediment processes, lack of control on exposure and transport, exposure pathways and receptors, and unique site characteristics such as public lands, lack of site control on use and access. The diversity of available assessment techniques for a sediment site is considerably larger than for other media. Guidance on the technical tools themselves are described in other ASTM guides and regulatory guidance manuals.  
4.2 Sediment-RBCA incorporates the same paradigm of planning and scoping, problem formulation, exposure and effects assessments, risk characterization, and uncertainty analysis that is common to ecological and human health risk assessment guidance documents. Irrespective of terminology, both Sediment-RBCA and risk assessment share the same science-based process and share the same goal of informing risk management decisions. The specific approach used to develop risk-based human health and ecological criteria and risk-based management plans may vary from site to site based on jurisdictional requirements, site complexity, TPDs, and best professional judgment regarding the appropriate use of different assessment techniques. Some attributes of Sediment-RBCA are:  
4.2.1 Description of a tiered approach, including process flow charts, to identify critical steps and provide an overview of the entire RBCA process;  
4.2.2 Identification, development, and use of TPDs throughout the Sediment-RBCA process...
SCOPE
1.1 Sediment-RBCA is based on protecting human health and the environment. The guide supplements the RBCA (Guide E2081) and Eco-RBCA (Guide E2205/E2205M) processes and provides a decision-making process for the management of contaminated sediment. Contaminated sediment sites vary greatly in terms of setting, usage, spatial and temporal complexity, and physical and chemical characteristics; and, therefore, they also vary greatly in terms of the risk that they may pose to human health and the environment. The Sediment-RBCA recognizes this diversity by using a tiered approach for gathering and evaluating data to determine the need for additional evaluation or risk management tailored to site-specific conditions and risks.  
1.2 This guide is intended to help direct and streamline the corrective action process and to complement (but not supersede) jurisdiction-specific guidance and regulations. It can be employed where jurisdiction-specific guidance is absent or insufficiently detailed; it can also assist to unify guidance when overlapping jurisdictions apply. It is compatible with a variety of programmatic guidelines for risk assessment and guidance from US Environmental Protection Agency (USEPA), Environment Canada, European, US states, that share the underlying risk assessment approach. In all applications, regulatory agencies should be consulted, as appropriate. Sediment-RBCA is not intended to apply to current permitted releases or permit applications.  
1.3 There are numerous TPDs related to the Sediment-RBCA process. Common examples are defining DQOs, identifying relevant receptors, defining toxicity values for risk evaluation, determining target risk levels, specifying the appropriate statistics and sample sizes, determining exposure assumptions, determining when and how to account for cumulative risks and additive effects among chemical(s) of concern, addressing resource protection, along with remedial action cons...

General Information

• Status: Published
• Publication Date: 31-Dec-2019
• ICS: 71.020 - Production in the chemical industry
• Technical Committee: E50 - Environmental Assessment, Risk Management and Corrective Action
• Drafting Committee: E50.04 - Corrective Action

Relations

• Refers: ASTM E3163-18 - Standard Guide for Selection and Application of Analytical Methods and Procedures Used during Sediment Corrective Action
• Effective Date: 01-Sep-2018
• Refers: ASTM E2893-16e1 - Standard Guide for Greener Cleanups
• Effective Date: 01-Apr-2016
• Refers: ASTM E2893-16 - Standard Guide for Greener Cleanups
• Effective Date: 01-Apr-2016
• Refers: ASTM E1739-95(2015) - Standard Guide for Risk-Based Corrective Action Applied at Petroleum Release Sites (Withdrawn 2024)
• Effective Date: 01-Apr-2015
• Refers: ASTM E2893-13e1 - Standard Guide for Greener Cleanups
• Effective Date: 15-Sep-2013
• Refers: ASTM E2893-13 - Standard Guide for Greener Cleanups
• Effective Date: 15-Sep-2013
• Refers: ASTM E1739-95(2010)e1 - Standard Guide for Risk-Based Corrective Action Applied at Petroleum Release Sites
• Effective Date: 01-Sep-2010
• Refers: ASTM E2081-00(2010)e1 - Standard Guide for Risk-Based Corrective Action
• Effective Date: 01-Sep-2010
• Refers: ASTM E2020-99a(2010) - Standard Guide for Data and Information Options for Conducting an Ecological Risk Assessment at Contaminated Sites
• Effective Date: 01-Mar-2010
• Refers: ASTM E2205/E2205M-02(2009)e1 - Standard Guide for Risk-Based Corrective Action for Protection of Ecological Resources
• Effective Date: 01-Mar-2009
• Refers: ASTM E1689-95(2008) - Standard Guide for Developing Conceptual Site Models for Contaminated Sites
• Effective Date: 01-Feb-2008
• Refers: ASTM E1848-96(2008) - Standard Guide for Selecting and Using Ecological Endpoints for Contaminated Sites
• Effective Date: 01-Feb-2008
• Refers: ASTM E2081-00(2004)e1 - Standard Guide for Risk-Based Corrective Action
• Effective Date: 01-Oct-2004
• Refers: ASTM E2081-00 - Standard Guide for Risk-Based Corrective Action
• Effective Date: 10-Apr-2000
• Refers: ASTM E1739-95(2002) - Standard Guide for Risk-Based Corrective Action Applied at Petroleum Release Sites
• Effective Date: 10-Sep-1995

Overview

ASTM E3240-20 - Standard Guide for Risk-Based Corrective Action for Contaminated Sediment Sites provides a comprehensive decision-making framework focused on the management of contaminated sediment sites. Developed by ASTM International under Committee E50, this standard outlines a transparent and consistent process known as Sediment-RBCA (Risk-Based Corrective Action), designed to protect both human health and the environment. Sediment-RBCA adapts general RBCA concepts from related ASTM guides (E1739, E2081, E2205/E2205M), emphasizing the special challenges found at sediment sites, such as sediment stability, recontamination risks, and complex exposure pathways. This framework uses a tiered approach, guiding site managers through increasingly detailed evaluations to ensure risk management decisions are scientifically defensible and tailored to site-specific conditions.

Key Topics

• Tiered Approach: Sediment-RBCA features a flexible, multi-level process, starting with an Initial Site Assessment (ISA) and progressing through Tier 1 (screening), Tier 2 (site-specific refinement), and Tier 3 (advanced risk assessment) evaluations. Each tier aims to reduce uncertainty and focus resources where most needed.
• Technical Policy Decisions (TPDs): Identifying and documenting crucial TPDs at each stage ensures the corrective action process aligns with regulatory requirements and site-specific challenges, such as defining Data Quality Objectives (DQOs), target risk levels, and relevant receptors.
• Stakeholder Engagement: The standard promotes broad participation from stakeholders, including regulators, local communities, and industry, to ensure transparent and inclusive risk management decisions.
• Risk Assessment Integration: Sediment-RBCA incorporates elements common to ecological and human health risk assessment-planning, problem formulation, exposure and effects assessment, risk characterization, and uncertainty analysis.
• Regulatory Compatibility: The guide supports and complements jurisdiction-specific regulations and can help unify guidance in cases of overlapping or insufficiently detailed regulatory frameworks. It is compatible with guidelines from agencies such as the US EPA, Environment Canada, and European counterparts.
• Performance Standards: Actions and decisions must be appropriately documented, sufficiently justified with data, and compliant with scientific principles, best practices, and applicable regulations.

Applications

The ASTM E3240-20 standard is applicable to a wide range of scenarios involving contaminated sediment management, including:

• Industrial and Urban Sediment Sites: Sites influenced by past or present industrial, municipal, or commercial activity, often characterized by complex contaminant distributions and multiple exposure pathways.
• Non-Urban Sediment Sites: Areas with limited point or non-point source discharges but still susceptible to contamination impacting ecological or human receptors.
• Site Characterization and Corrective Action: Using Sediment-RBCA to conduct site assessments, identify contaminants of concern, prioritize remedial actions, and monitor effectiveness for ongoing or historical releases.
• Regulatory Program Support: Filling gaps in guidance where regulatory detail is lacking, or harmonizing requirements across overlapping jurisdictions.
• Stakeholder-Driven Decision Making: Facilitating engagement with potentially affected parties, including local communities, indigenous groups, and natural resource trustees, to develop transparent, defensible corrective action plans.

By following ASTM E3240-20, practitioners ensure that corrective actions at sediment sites are risk-based, technically sound, and responsive to the varied challenges posed by different site types and regulatory environments.

Related Standards

Several ASTM and regulatory documents complement or are referenced by ASTM E3240-20:

• ASTM E2081: Guide for Risk-Based Corrective Action
• ASTM E2205/E2205M: Guide for Risk-Based Corrective Action for Protection of Ecological Resources
• ASTM E1739: Guide for RBCA at Petroleum Release Sites
• ASTM E3163: Guide for Analytical Methods during Sediment Corrective Action
• ASTM E3164: Guide for Sediment Corrective Action - Monitoring
• EPA QA/G-4 (USEPA 2006): Guidance on Data Quality Objectives
• Environment Canada Guidelines: For site risk assessment and management

ASTM E3240-20 thus serves as a critical reference for risk-based sediment site management, ensuring protection of both human and ecological health through a standardized, transparent process.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E3240 − 20
Standard Guide for
Risk-Based Corrective Action for Contaminated Sediment
Sites
This standard is issued under the fixed designation E3240; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
This guide provides a framework for the development of a Risk-Based CorrectiveAction (RBCA)
process for contaminated sediment sites (Sediment-RBCA) that integrates ecological and human
health risk-based decision making into the corrective action process. Sediment-RBCAguide parallels
the RBCA frameworks in Guides E2081 and E2205/E2205M with respect to the tiered approach for
data gathering, evaluation and decision-making, and should, when possible, be conducted concurrent
with broader RBCAactivities. Sediment-RBCAprovides a flexible, technically defensible framework
for corrective action that can be applied to a wide range of sites and chemicals of concern. The
framework incorporates a tiered technical approach, using increasingly complex levels of data
collection and analysis as the user proceeds through the process.
This guide is intended to be used in conjunction with E3163 – Standard Guide for Selection and
Application of Analytical Methods and Procedures Used during Sediment Corrective Action and
E3164 – Standard Guide for Sediment CorrectiveAction – Monitoring. Successful implementation of
theSediment-RBCAprocessrequiresthattheuseridentifiesthetechnicalpolicydecisions(TPDs)that
arecriticaltotheriskmanagementprocessandidentifytheseTPDspriortobeginningtheprocess(see
5.5.3). There are numerous TPDs that must be made to implement the RBCA process, for example,
defining data quality objectives (DQOs), identify relevant receptors, defining background and site
exposure and toxicity data/inputs for risk evaluation, determining target risk levels, addressing
resource protection, and implementing risk management. It is not the intent of this guide to define
appropriate TPDs.
The Sediment-RBCA encourages broad stakeholder involvement in both the development of the
TPDs and progression through the tiered analysis. This guide recognizes the diversity of sites and
provides supporting appendices for additional information, with the intent of sharing industry best
practices.
1. Scope gathering and evaluating data to determine the need for
additional evaluation or risk management tailored to site-
1.1 Sediment-RBCA is based on protecting human health
specific conditions and risks.
andtheenvironment.TheguidesupplementstheRBCA(Guide
E2081) and Eco-RBCA(Guide E2205/E2205M) processes and
1.2 This guide is intended to help direct and streamline the
provides a decision-making process for the management of
corrective action process and to complement (but not super-
contaminated sediment. Contaminated sediment sites vary
sede) jurisdiction-specific guidance and regulations. It can be
greatly in terms of setting, usage, spatial and temporal
employed where jurisdiction-specific guidance is absent or
complexity, and physical and chemical characteristics; and,
insufficientlydetailed;itcanalsoassisttounifyguidancewhen
therefore, they also vary greatly in terms of the risk that they
overlapping jurisdictions apply. It is compatible with a variety
mayposetohumanhealthandtheenvironment.TheSediment-
of programmatic guidelines for risk assessment and guidance
RBCArecognizes this diversity by using a tiered approach for
from US Environmental Protection Agency (USEPA), Envi-
ronment Canada, European, US states, that share the underly-
ThisguideisunderthejurisdictionofASTMCommitteeE50onEnvironmental
ing risk assessment approach. In all applications, regulatory
Assessment, Risk Management and CorrectiveAction and is the direct responsibil-
agencies should be consulted, as appropriate. Sediment-RBCA
ity of Subcommittee E50.04 on Corrective Action.
is not intended to apply to current permitted releases or permit
Current edition approved Jan. 1, 2020. Published May 2020. DOI: 10.1520/
E3240–20 applications.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E3240 − 20
1.3 There are numerous TPDs related to the Sediment- 1.9.4 Section 5 describes the tiered approach to the
RBCA process. Common examples are defining DQOs, iden- Sediment-RBCA process;
tifying relevant receptors, defining toxicity values for risk 1.9.5 Sections 6 and 7 present Sediment-RBCA procedures
evaluation, determining target risk levels, specifying the ap- in a step-by-step process; and
propriate statistics and sample sizes, determining exposure 1.9.6 The reference section lists documents cited in this
assumptions, determining when and how to account for cumu- guide.
lative risks and additive effects among chemical(s) of concern,
1.10 This guide also includes the following appendices,
addressing resource protection, along with remedial action
which are provided as supplemental information:
constraints (RACs). It is not the intent of this guide to define
1.10.1 Appendix X1: Considerations for Design and Execu-
appropriate TPDs. Users should be aware of jurisdiction-
tion of Weight of Evidence (WOE) Approaches in Sediment
specific guidance and should seek approvals and/or technical
Risk Assessment;
policy input as applicable.
1.10.2 Appendix X2: Use of Sediment Quality Guideline
Values (SQGs) in Screening Level Ecological Risk Assess-
1.4 The general performance standard for this guide re-
ments (SLERAs);
quires that:
1.10.3 Appendix X3: Derivation and Use of Site-specific
1.4.1 TPDs will be identified early in the Sediment-RBCA
Ecological Criteria (SSEC) in Ecological Risk Assessments;
process and reevaluated throughout the process (at each tier),
1.10.4 Appendix X4: Uncertainty in Risk Evaluation;
1.4.2 Data and information compiled during the Sediment-
1.10.5 Appendix X5:Application of ReferenceArea Data in
RBCA process, including historical data and new data col-
Sediment Ecological Risk Assessment;
lected during the site assessment, will be relevant to and of
1.10.6 Appendix X6: Biological Test Methods, and
sufficient quantity and quality to answer the questions and
1.10.7 Appendix X7: Guidance for Developing RAOs.
support the decisions made at each tier of investigation,
1.11 This standard does not purport to address all of the
1.4.3 Actions taken during the risk-based decision-making
safety concerns, if any, associated with its use. It is the
process will be protective of human health and the
responsibility of the user of this standard to establish appro-
environment, consistent with current scientific principles and
priate safety, health, and environmental practices and deter-
practices, and in accordance with jurisdiction-specific require-
mine the applicability of regulatory limitations prior to use.
ments (for example, regulations, policies, and guidance), and
1.12 This international standard was developed in accor-
1.4.4 Remedial actions implemented consistent with TPDs
dance with internationally recognized principles on standard-
and the Sediment-RBCA process will not result in greater
ization established in the Decision on Principles for the
long-term risks than existed before taking actions.
Development of International Standards, Guides and Recom-
1.5 There are basic elements common to all RBCA guides:
mendations issued by the World Trade Organization Technical
1.5.1 site assessment;
Barriers to Trade (TBT) Committee.
1.5.2 tiered evaluations of exposure, effects, and risk;
2. Referenced Documents
1.5.3 risk-based decision making;
1.5.4 remedial action, and
2.1 ASTM Standards:
1.5.5 monitoring.
E1689 Guide for Developing Conceptual Site Models for
Contaminated Sites
1.6 This Sediment-RBCA focuses on releases of chemicals
E1739 Guide for Risk-Based Corrective Action Applied at
from sediment and is intended to be a companion to Guides
Petroleum Release Sites
E1739, E2081, and E2205/E2205M. Risks to human health
E1848 Guide for Selecting and Using Ecological Endpoints
from contaminated sites are discussed in Guides E1739 and
for Contaminated Sites
E2081, while risks to ecological receptors are discussed in
E2020 GuideforDataandInformationOptionsforConduct-
Guide E2205/E2205M and Guide E2020.
ing an Ecological RiskAssessment at Contaminated Sites
1.7 Both human health and ecological resource risks from
E2081 Guide for Risk-Based Corrective Action
contaminated sediment are addressed in this guide. Guidance
E2205/E2205M Guide for Risk-Based CorrectiveAction for
on conducting human health and ecological risk assessments is
Protection of Ecological Resources
available, including from various regulatory agencies, pub-
E2876 Guide for Integrating Sustainable Objectives into
lished literature, and scientific associations (see Appendix X1
Cleanup
to Appendix X7, Guide E2205/E2205M, and Guide E2020).
E2893 Guide for Greener Cleanups
E3163 Guide for Selection and Application of Analytical
1.8 For sites that warrant remedial action, guidance is
Methods and Procedures Used during Sediment Correc-
provided on developing remedial Action Objectives (RAOs)
tive Action
(Appendix X7) that support a remedial action plan.
E3164 Guide for Sediment Corrective Action – Monitoring
1.9 This guide is organized as follows:
1.9.1 Section 2 lists referenced ASTM documents;
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1.9.2 Section 3 defines terminology used in this guide;
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
1.9.3 Section 4 describes the significance and use of this
Standards volume information, refer to the standard’s Document Summary page on
guide; the ASTM website.
E3240 − 20
2.2 EPA Documents: able risk to human health or the environment, the term should
USEPA (2006) Guidance on Systematic Planning Using the not automatically be construed to be associated with increased
Data Quality Objective Process: EPA QA/G-4. EPA/240/ or unacceptable risk. E2081
B-06/001
3.2.8 conceptual site model (CSM), n—a written
USEPA (2015) Determination of the Biologically Relevant
description, visual representation, or both, of predicted rela-
Sampling Depth for Terrestrial and Aquatic Ecological
tionships between relevant ecological receptors and habitats
Risk Assessments, Ecological Risk Assessment Support
and/or relevant human receptors, and the COCs to which they
Center, Washington, DC
maybeexposed.CSMsdescribepredictedrelationshipsamong
COCs in environmental media (water, sediment, biological
3. Terminology
tissue, etc.) via fate and transport pathways, exposure
3.1 The user should be familiar with the definitions pre-
pathways, and relevant receptors. The CSM should include
sentedherebeforereadingtheremainderofthisguide,asmany
both the current understanding of the site and the understand-
of the terms might have specific definitions within jurisdiction
ing of the potential future conditions and uses for the site.
specific guidance that vary from that used in this guide. The E2205/E2205M
following terms are being defined to reflect their specific use in
3.2.9 contaminant, n—a hazardous substance as defined by
this guide. The definitions presented here are intended to be
federal, state/provincial, or international regulation, petroleum
consistent with those provided in Guides E2081 and E2205/
product, or other chemical that may pose a threat to human
E2205M.
health or the environment when present in environmental
3.2 Definitions of Terms Specific to This Standard:
media. E2893
3.2.1 adaptive management, n—a structured, iterative pro-
3.2.10 corrective action, n—the sequence of actions that
cess of robust decision making in the face of uncertainty, with
mayincludesiteassessmentandinvestigation,riskassessment,
the goal of ensuring effectiveness during remedial action.
evaluations of potential remedial action alternatives, interim
3.2.2 assessment endpoint, n—the explicit expression of the
remedial action, remedial action, operation and maintenance of
environmental value that is to be protected, operationally
the remedy, monitoring of progress, making “No Further
defined by an ecological entity and its attributes. The term
Action”determinations,andcompletionoftheremedialaction.
“ecological entity” in this standard is equivalent to “relevant
3.2.11 data quality objectives (DQOs), n—the systematic
ecological receptors and habitats.” Additional information
process to develop performance and acceptability criteria by
regarding assessment endpoints can be found in Guide E1848.
defining study objectives and the type, quality, and quantity of
E2205/E2205M
data needed for site decisions. USEPA (2006)
3.2.3 background conditions (aka reference conditions),
3.2.12 ecological risk, n—the potential for or probability of
n—substances, conditions, or locations that are not influenced
an adverse effect on a relevant ecological receptor or habitat
by the releases from a site and are either naturally occurring
(including populations or communities). These risks may be
(consistently present in the environment, but not influenced by
expressed qualitatively or quantitatively.
human activity) or anthropogenic (influenced by human
3.2.13 evaluation criteria, n—thecriteriabywhichremedial
activity, but not related to specific activities at the site). E3164
technologies and remedial actions are evaluated in remedial
3.2.4 bioavailability, n—the degree to which a contaminant
decision making.
is free to be taken up by an organism.
3.2.14 human health risk, n—the potential for or probability
3.2.5 biologically active zone (aka biotic zone), n—the zone
of an adverse effect on a human receptor. These risks may be
of greatest organism-substrate interaction. USEPA (2015)
expressed qualitatively or quantitatively.
3.2.6 chemical(s) of concern (COCs), n—COCs are chemi-
3.2.15 industrial sites, n—sites where there were or are
cal or constituents that are identified as posing a risk based on
industrial facilities that discharged or currently discharge
the tiered assessment that warrant remedial action; the COCs
COCs into a contiguous area in a water body.
are a subset of chemicals of potential concern (COPCs).
3.2.16 initial site assessment, n—an initial assessment of a
3.2.7 chemical(s) of potential concern (COPCs), n—the
specific compounds and their breakdown products, along with sediment site that relies on readily available information for
determining whether a risk assessment might be appropriate,
mixtures and other constituents, that are identified for evalua-
tion in the Sediment-RBCA process. Identification can be whether a response action is appropriate to mitigate an imme-
diate threat, or a no further action determination is warranted.
basedonchemicals’historicalandcurrentuseatasite,detected
concentrations in environmental media or their mobility,
3.2.17 institutional controls, n—a legal or administrative
toxicity, and persistence in the environment. Because COPCs
restriction on the use of, or access to a site or facility to
may be identified at many points in the RBCA process,
eliminate or minimize potential exposure to a COC(s) (restric-
including before any determination that they pose an unaccept-
tive covenants, restrictive zoning, access restrictions, fish
consumption advisories, etc.). E2081
3.2.18 interim remedial action, n—the course of action,
AvailablefromUnitedStatesEnvironmentalProtectionAgency(EPA),William
prior to final remedial action, taken to reduce transport of a
Jefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,
http://www.epa.gov. COC(s) in sediment or water, or to reduce the concentration of
E3240 − 20
a COC(s) at a source area(s). These include remedial actions depending on the tier of the Sediment-RBCA and range from
that are taken to address imminent risks to human health and genericRBSLsusedfortheinitialscreeningsteps,toliterature-
the environment. based RBSLs typically used in Tier 1 or 2, to detailed,
site-specific RBSLs derived from Tier 3 investigations.
3.2.19 measure of effect, n—a change in an attribute of an
3.2.28 risk characterization, n—the integration of the re-
assessment endpoint or its surrogate in response to a stressor to
which it is exposed. Measures of effect are also referred to as sults of the exposure and effects analysis to evaluate the
likelihood of adverse human health and/or ecological effects
measurement endpoints. E2205/E2205M
associated with exposure to COCs.
3.2.20 non-urban sites, n—sites where there were few
3.2.29 risk management, n—the consideration of scientific
former industrial, public, or commercial facilities and where
factors, economic factors, legal decisions, social factors, and
therearelimitedpoint-sourceandnon-point-sourcedischarges.
technological factors to develop a response to identified risks.
Sites may include residential properties or agricultural proper-
ties.
3.2.30 sediment, n—a matrix of pore water and particles
including gravel, sand, silt, clay, and other natural and anthro-
3.2.21 reasonably anticipated future use, n—current and
pogenic substances that have settled at the bottom of a body of
likely future use of a site or facility which can be predicted
water. E3163
with a reasonably high degree of certainty.
3.2.31 sediment site, n—the area(s) defined by the likely
3.2.22 relevant ecological receptors and habitats, n—the
physical distribution of the COC(s) from a source area and the
ecological resources that are valued at the site. Because of the
adjacent areas required to implement the corrective action. A
variety of ecological resources that may be present, focusing
site could be an entire water body or a defined portion of a
uponthoserelevanttoasiteisanimportantpartoftheproblem
water body.
formulation. Identification of relevant ecological receptors and
habitats is dependent upon site-specific factors and TPDs.
3.2.32 site assessment, n—a characterization of a site
through an evaluation of its physical and environmental
3.2.23 relevant human receptor, n—human receptor that
context (for example, subsurface geology, sediment properties
may be reasonably expected to be exposed to COCs in
and structures, hydrology, and surface characteristics) to deter-
environmental media (water, sediment, biological tissue, etc.)
mine if a release has occurred. The characterization may
given current and foreseeable uses of the waterway.These may
identify the concentration and distribution of COCs. Informa-
include human receptors such as recreational users (boating,
tion collected during the site assessment may include data on
wading, swimming, fishing, crabbing), tribes (subsistence
sediment, groundwater, and surface water quality, land and
fishing), construction workers, those working on the waterway,
resource use, and potential human and ecological receptors.
or other site-specific receptors.
This information is used to develop a CSM and support
3.2.24 remedial action, n—activities conducted to reduce or
risk-based decision making. E2205/E2205M
eliminate current or potential future exposures to receptors or
3.2.33 site-specific, n—activities, information, and data
relevant ecological receptors and habitats. These activities
unique to a particular site. E2081
include monitoring, implementing activity and use limitations
3.2.34 stakeholders, n—individuals, organizations or other
and designing and operating cleanup equipment. Remedial
entities that affect or are affected by the site conditions, the
action includes activities that are conducted to reduce sources
ofexposuretomeetRAOs,orseverexposurepathwaystomeet corrective action, or both. Stakeholders might include, but are
not limited to, Potentially Responsible Parties (PRPs), owners,
RAOs.
buyers, developers, lenders, insurers, government agencies,
3.2.25 remedial action objectives (RAO), n—stated objec-
Tribes, community members, indigenous authorities, natural-
tives that describe what the remedial action for a site is
resource trustees, and non-governmental or local community
expected to accomplish, based on the CSM and the exposure
organizations. E2205/E2205M
pathways that may pose an unacceptable risk as determined in
3.2.35 stressor, n—a chemical, physical, or biological agent
a risk assessment. RAOs are specific and achievable goals for
or condition that causes stress to an organism.
reducing risk to human health and the environment.
3.2.36 sustainability, n—the selection of remedial action
3.2.26 risk assessment, n—an analysis of the potential for
decisions that balance community goals, economic impacts,
adverse effects on relevant human or ecological receptors
and environmental effects.
caused by a COC from a site. The risk assessment results
support a decision on whether interim remedial actions, reme-
3.2.37 sustainable objective, n—the overarching ideas and
dial action or a combination of actions are required, and form themes used to guide the implementation of sustainability for a
the primary basis for the development of RAOs.
project.These ideas and themes generally arise from outside of
the specific project (state/provincial or federal regulations or
3.2.27 risk-based screening level (RBSL), n—a chemical
guidance, municipal planning goals, corporate sustainable
concentration or dose that is deemed to be protective for a
objectives, etc.) and are not developed exclusively for the
given pathway and receptor (ecological or human). Covers a
specific project. E2876
wide range of similar terms coined by jurisdiction-specific
guidance manuals or other ASTM guides, including relevant 3.2.38 technical policy decisions (TPDs), n—the choices
ecological screening criteria, SQGs, SSECs, site-specific target specific to the user that are necessary to implement the RBCA
levels (SSTLs), toxicity reference values (TRVs). RBSLs vary framework described in this guide at a particular site. E2081
E3240 − 20
3.2.39 tier 1 evaluation, n—a screening-level assessment 4.2.1 Description of a tiered approach, including process
that uses existing information, nonsite-specific screening flow charts, to identify critical steps and provide an overview
criteria, and protective assumptions to ensure that risks are not of the entire RBCA process;
underestimated.
4.2.2 Identification,development,anduseofTPDsthrough-
out the Sediment-RBCA process;
3.2.40 tier 2 evaluation, n—a risk-based analysis that in-
4.2.3 Indications of the value and timing of stakeholder
volves an incremental refinement of the Tier 1 methodology to
involvement, recognizing that some jurisdictions require vary-
develop site-specific screening criteria.
ing degrees of coordination with a variety of stakeholders;
3.2.41 tier 3 evaluation, n—a risk-based analysis that in-
4.2.4 Identification of situations under which a risk assess-
volves a significantly advanced incremental effort over theTier
ment may or may not be necessary;
2 evaluation to assess site-specific risks.
4.2.5 Identificationofdecisionpointswhereriskassessment
3.2.42 unacceptable risk, n—a condition under which the
results are used as part of the risk management decision
likelihood of adverse effects to relevant human and/or ecologi-
making; and
cal receptors and habitats is not within acceptable limits as
4.2.6 Identification and development of appropriate RAOs
defined by TPDs. E2205/E2205M
to support risk management.
3.2.43 uncertainty, n—the lack of knowledge regarding site
4.3 Activities described in this guide should be conducted
conditions, the nature of exposure, and effects on relevant
by qualified professionals familiar with site characterization,
human or ecological receptors and habitats. This lack of
remedial action science and technology, human health and
knowledge is recognized at each tier of evaluation through an
ecological risk assessment methodologies, or related scientific
uncertainty analysis. E2205/E2205M
and engineering subject areas, as they relate to complex
sediment sites. A defensible application of a RBCA process is
3.2.44 urban sites, n—a site where there are industrial,
municipal, commercial, or residential properties with multiple often a collaboration of multiple subject matter experts.
point-sourceandnon-point-sourcedischargesintoacontiguous
4.4 To properly apply the Sediment-RBCAprocess, the user
water body.
should AVOID the following:
4.4.1 Using Tier 1 RBSLs as a default remedial action
4. Significance and Use
standard without considering if proceeding to develop more
4.1 This guide provides a consistent and transparent refined RBSLs through a Tier 2 or Tier 3 evaluation is
appropriate;
decision-making process for selecting risk-based corrective
actions at sediment sites (that is, a Sediment-RBCA).
4.4.2 Placing arbitrary time constraints on the corrective
Sediment-RBCA shares the same process as other RBCAs action process that do not reflect the actual urgency and risk
described in E1739, E2081, and E2205/E2205M but with
posed by the site;
explicit consideration of the constraints on how the available
4.4.3 Failing to document the purpose of the Sediment-
sediment assessment techniques impact decision making. Sev-
RBCA process (that is, defining the management goal per the
eral factors exist that distinguish sediment sites from upland
problem formulation requirement) and connecting that man-
sites and warrant unique consideration, including background,
agement goal to the specific assessment techniques in a logical
potential for recontamination, sediment stability, sediment
and transparent way (that is, developing a clear set of assess-
processes, lack of control on exposure and transport, exposure
ment endpoints and measures of effects per risk assessment
pathways and receptors, and unique site characteristics such as
guidance);
public lands, lack of site control on use and access. The
4.4.4 Using unjustified or inappropriate exposure factors,
diversity of available assessment techniques for a sediment site
toxicity parameters, or other assumptions required by an
is considerably larger than for other media. Guidance on the
assessment technique or applying a model that is not supported
technical tools themselves are described in otherASTM guides
by site-specific data;
and regulatory guidance manuals.
4.4.5 Developing ecologically-based RBSLs from data that
do not exhibit a dose- or concentration-response relationship,
4.2 Sediment-RBCA incorporates the same paradigm of
or failing to consider cumulative risks or additive effects when
planning and scoping, problem formulation, exposure and
required to do so by jurisdiction-specific guidance;
effects assessments, risk characterization, and uncertainty
4.4.6 Neglecting aesthetic, narrative, or other constraints
analysis that is common to ecological and human health risk
when using RBSLs to establish the RAOs for a site;
assessment guidance documents. Irrespective of terminology,
both Sediment-RBCA and risk assessment share the same 4.4.7 Initiating remedial action(s) (other than an action
science-based process and share the same goal of informing taken to address imminent or priority issues) before determin-
risk management decisions. The specific approach used to ingtheappropriateRAOsforthesite.RAOsmustbeattainable
develop risk-based human health and ecological criteria and using existing technology (that is, technically practicable and
risk-based management plans may vary from site to site based cost effective) and must reflect the desired long-term outcome
on jurisdictional requirements, site complexity, TPDs, and best for a sediment site in the context of current and realistic future
professional judgment regarding the appropriate use of differ- site uses, as well as background concentrations and the
entassessmenttechniques.SomeattributesofSediment-RBCA potential for recontamination. It is also inappropriate to pro-
are: ceed with remedial action(s) without consideration of site
E3240 − 20
source-control measures (due to the potential for recontamina- 5.5 Sediment-RBCA does not have to be a linear process
tion from uncontrolled sources). and should proceed only to the point that a defensible decision
can be made. The level of effort at any given tier is ultimately
4.4.8 Limiting remedial action options to a single type of
a project-specific decision that can be influenced by one or
remedial technology, failing to consider options for remedial
more of the following factors:
activity or failing to consider use limitations of remedial
technologies. In all cases, a robust remedial options analysis
5.5.1 Timing and Urgency of Response Actions—Moving
that is not biased towards a particular remedial action option is
directly toTier 2 or 3 early in Sediment-RBCAprocess may be
needed;
appropriate if preliminary information indicates significant
human health or ecological risks likely exist. Accelerating
4.4.9 Using an interim remedial action to delay the RBCA
Sediment-RBCA may also make sense if there is an opportu-
process rather than to reduce risk;
nity to integrate remedial actions with other site management
4.4.10 Failing to consider the impact of a potential remedial
activities (for example, habitat enhancements, flood mitigation
action on relevant receptors as part of the selection process;
projects, maintenance dredging).
4.4.11 Failing to consider the long-term effectiveness of a
5.5.2 Stakeholder Feedback—The nature and frequency of
potential remedial action during the selection process, or
stakeholder engagement depends on jurisdiction- and site-
failing to monitor the effectiveness of the option once selected
specific requirements.There is no single model for stakeholder
and implemented; and
engagement and many sites may not require a formal stake-
4.4.12 Continuing to monitor a site once the RAOs have
holder process. Further context about stakeholder engagement
been achieved (unless the RAOs were explicitly designed to
in RBCA projects can be found in Appendix X1.5 of E2205/
involve such monitoring). (Guide E3164)
E2205M andAppendix X1 of E2081. Stakeholder engagement
can influence all parts of the process including the scope and
5. Tiered Approach to RBCA for Contaminated
tiering of the Sediment-RBCA process.
Sediment Sites
5.5.3 Regulatory Input and TPDs—Practitioners are cau-
5.1 Sediment-RBCA is the overall process of integrating
tionedthatsignificanteffortmaybeneededtoobtainconsensus
site assessment, risk assessment, remedial action, and monitor-
on how specific TPDs will be applied on a site-specific basis.
ing at sites where a chemical release to sediment has occurred.
TPDs specifically for sediment are not available for many of
The decision-making process in Sediment-RBCA integrates
the more complex investigative tools typically used in Tier 3.
both human health and ecological considerations (Guide
There is a need to select relevant TPDs for the current tier and
E2081).
appropriatelyapplythem.ThethreegeneralcategoriesofTPDs
are (1) those that exist prior to beginning the Sediment-RBCA
5.2 Sediment-RBCA progresses through one or more tiers
process and will not change because they are prescribed by
untilithasproceededtothepointadefensibleconclusionabout
regulation or policy, (2) those that exist prior to the Sediment-
the magnitude of risk can be made, RAOs can be defined, and
RBCAbut can be modified based on site-specific information,
anappropriateremedialaction(whichmayalsoincludeinterim
and (3) those that are developed specifically as part of the
remedial actions) can be selected. The tiered process begins
site-specific Sediment-RBCA process. Some regulatory agen-
with an Initial Site Assessment using available site data and
cies may also default (inappropriately) to TPDs that are based
appropriate RBSLs (typically specified by the jurisdiction). If
on upland considerations, for example using soil standards for
those initial RBSLs are exceeded, Sediment-RBCAguides the
the protection of human health to screen sediment data. Guides
user to proceed to subsequent tiers as discussed in Section 6.
E2081 (Appendix X1) and E2205/E2205M (Appendix X3)
5.3 Each tier of Sediment-RBCA involves the same five
provide additional information on considerations for establish-
steps (Fig. 1: Planning and scoping; Data and information
ing TPDs. Regulatory engagement is often central to the
acquisition; Analysis and evaluation; Decision-making; and
success of a Sediment-RBCA process, especially those that
Remedialaction)butwithincreasingrealismandcomplexityin
proceed to higher tiers and incorporate less common assess-
the selected assessment methods with each successive tier.
ment tools.
5.4 Sediment-RBCA emphasizes flexibility in how the 5.5.4 DQOs—DQOs are developed for all sampling and
evaluation process is tailored to site conditions and require- analytical activities. These DQOs should be reviewed as the
ments. This flexibility is necessary due to the wide variety of assessment progresses from tier to tier. Guide E3163 and
methodsusedtoevaluatehumanhealthandecologicalrisk(see USEPA (2006) provide more information about how to estab-
Appendix X1 through Appendix X6; E2205/E2205M). The lish defensible DQOs for a variety of different sampling and
specific methods selected for each tier should focus on provid- analytical activities. The flexibility of Sediment-RBCA also
ing the quality and quantity of data necessary to support means that it is relatively common to incorporate more
risk-based decision making as defined by DQOs. As noted innovative methods into a Tier 3 Sediment-RBCA. These
above, the complexity and sophistication of the methods methods may not yet be familiar to all users and may involve
increase with each tier to reduce the uncertainty in the different types of DQOs beyond the traditional ones applied to
decision-making process.Acorollary is that COPCs, portion(s) chemical and toxicological analyses. Regardless, all methods
of a site, exposure pathways, and/or receptors that can be must have DQOs in order to determine how much weight the
eliminated at an early tier should not be revisited in subsequent data should receive in terms of making an informed site
tiers unless new information warrants re-inclusion. management decision (see Appendix X1).
E3240 − 20
FIG. 1 Sediment-RBCA Process Flowchart
5.5.5 Degree of Acceptable Uncertainty—There is always but in all respects, the uncertainty should be clearly docu-
uncertainty in both the site assessment and risk evaluation mented (10.1.1) to show that the information is adequate to
components at any tier (see Appendix X4). The level of make an informed risk management decision. The degree of
conservatism in each subsequent tier will generally decrease as acceptable uncertainty may also be a TPD that warrants
theuncertaintyintheassessmentandriskevaluationdecreases, specific dialogue with regulatory agencies and stakeholders.
E3240 − 20
6. Sediment-RBCA Procedures or if receptors are present or absent. A CSM for an ISA is
typically more about documenting the identified data gaps to
6.1 Thesequenceofprincipaltasksanddecisionsassociated
help focus future sampling than making a definitive statement
with the Sediment-RBCA process are outlined in Fig. 1. Each
about specific contaminants, sources, pathways and receptors,
of these actions and decisions is discussed in the following
as illustrated in Fig. 2.
sections. For the purposes of this guide, guidance is provided
6.2.4.2 Comparison to RBSLs—It is common to compare
for the Initial Site Assessment, the Tier 1 evaluation and then
any available sediment chemistry data to applicable RBSLs
the Tier 2+ Sediment-RBCA. The distinction between Tier 2
using a hazard quotient approach. It may be necessary to
and Tier 3 evaluations is related to the site characteristics; the
compare sediment chemistry data to RBSLs from a different
difference between Tier 2 and Tier 3 can be loosely defined by
jurisdiction (which is another TPD that may require early
increasing complexity of the assessment (see Table 1). As
regulatory engagement).
noted in Section 5, the Sediment-RBCAprocess is intended to
be highly flexible allowing for the application of various tools
6.2.5 Decision Making—The ability to make a no further
and analytical methods at either tier. Identification of specific
action or a response action decision at the completion of the
tools or analytical methods in the following sections are
ISA is frequently limited due to the lack of sufficient existing
intended to reflect common approaches and are not intended as
data. If complete or potentially complete exposure pathways
prescriptive guidance.
are identified after developing the CSM based on available
data, then a Tier 1 evaluation should be conducted.
6.2 Initial Site Assessment (ISA)–—The ISAis performed to
6.2.6 Remedial Action—The ISA will lead to a Tier 1
review existing information for determining if an initial re-
Sediment-RBCA for many sites but can lead to no further
sponse action is required to mitigate an immediate threat,
action in two specific scenarios.
further tiered evaluation is required, or if a no further action
determination can be made (Fig. 1).
6.2.6.1 The ISA can conclude that no further action is
6.2.1 Objective of the ISA—The ISA is a planning and
warranted (that is, stop the Sediment-RBCA process) when
scoping activity that develops the CSM based on an initial
there is compelling and sufficient existing site-specific data to
understanding of the site. This planning and scoping activity is demonstrate that all chemical concentrations in site sediments
a critical part of implementing the TPDs due to the potential
are less than the applicable RBSLs or that there are no
complexity of human and ecological exposure pathways at completed pathways to receptors at the site. RBSLs in this
sedimentsites.TheISAincorporatesthesamemainstepsasthe
scenario would be default nonsite-specific, conservative, and
subsequent tiered evaluations (Sections 6.3 and 6.4) but does chemical-specific values that are associated with a clear TPD
not involve any new site-specific sampling.
that a no further action decision is supported.
6.2.2 Planning and Scoping—The focus of the planning and
6.2.6.2 The ISA can conclude that a response action is
scoping effort is establishing a preliminary boundary for the
appropriate if there is compelling and sufficient site-specific
study area, identifying the applicable regulatory TPDs, identi-
data to demonstrate that there is an imminent and unacceptable
fying and engaging stakeholders, and determining if there are
risk to priority receptors identified in the CSM. The Sediment-
appropriate RBSLs available to make an informed decision.
RBCA process continues (after the response action is imple-
6.2.3 Data and Information Acquisition—The data and in-
mented) to determine the appropriate RAO(s) and final correc-
formation acquisition activities for the ISA are limited to
tive actions (that is, remedial action[s]). A decision to
existing site reports or other readily available sources of
implement a response remedial action based on the ISA
information. This step is often more about compiling the
typically requires a clear TPD to define what constitutes a
available information and documenting the data gaps to be
priority receptor and what constitutes an imminent unaccept-
addressed in Tier I. Data gaps can also include the absence of
able risk. Human receptors are more likely to be a priority for
appropriate TPDs and RBSLs.
these early response actions, although some jurisdictions may
6.2.4 Analysis and Evaluation—Theanalysisandevaluation
have legislation that mandates immediate action for certain
in an ISA consists of two main activities.
ecological receptors (for example, prevention of acute lethality
6.2.4.1 Preparation of a Preliminary CSM—A preliminary
to specific, protected species).
CSM is developed during the ISA to facilitate overall under-
6.3 Tier 1 Evaluation:
standingofthesite,serveasavaluabletoolforcommunicating
6.3.1 Objective of the Tier 1 Evaluation—The Tier 1 evalu-
the understanding of the site to stakeholders, and assisting in
ation incorporates a screening-level risk assessment. As with
the decision-making process. The CSM describes the hypoth-
all screening-level risk assessments, the level of complexity in
eses that form the basis of the Sediment-RBCA evaluation by
the selected assessment methods is intentionally low, and the
relating the potential chemicals of concern, fate and transport
degreeofconservatismisintentionallyhigh.Thisconservatism
mechanisms, potential exposure pathways, and relevant recep-
extends throughout all aspects of the decision-making process
tors. Information collected during the ISAmay identify incom-
for a Tier 1 evaluation. The Tier 1 evaluation uses the data and
plete exposure pathways that may eliminate the need for any
information collected for the ISA, as well as any additional
further evaluation of one or more (or all) exposure pathways or
data collected specifically for Tier 1.
the site as a whole. The CSM will be iteratively revised and
updatedasadditionalsiteinformationisobtainedinsubsequent 6.3.2 Planning and Scoping—The planning and scoping for
tiers, as needed. In many cases, the data will not be sufficient aTier1evaluationistypicallyfocusedonaddressingthemajor
to determine if exposure pathways are operable or inoperable, data gaps identified in the ISA. The Tier 1 planning and
E3240 − 20
A
TABLE 1 Sediment-RBCA Tier Content Comparison
Sediment-RBCA
Initial Site Assessment Tier 1 Tier 2 Tier 3
Component
Data Compilation Compile Existing/Historical Initial Sampling: To fill data Site-Specific Sampling: Compile site specific data
Data: Obtain existing gaps previously identified, Compile site-specific and other information to
sediment data and other compile bulk sediment information to refine perform detailed risk
relevant information chemistry and TOC data to exposure estimates and fill assessment
acquired from prior reports obtain chemical data gaps; consider
and site assessments, a concentrations in contaminant forms and
site visit, records of sediments to identify initial species, and chemical
historical site activities, or COCs and an initial mixtures
chemical releases or spills; estimate of bioavailability
identify meaningful data
gaps
Site Visit Conduct an initial site visit Compile source, pathway Collect select site-specific Conduct field study to
to compile information and and receptor data; Collect information to refine CSM, collect data and other
record observations to bulk sediment and TOC including receptor groups information to fill remaining
inform the initial CSM data to assess contaminant and their use of the site data gaps for calculating
bioavailability estimates of
bioaccumulation, benthic
surveys, etc.
Conceptual Site Model Preliminary CSM: include Refine CSM: include Refine CSM: include site Refine CSM: adjust as
(CSM) an initial identification of exposure pathways, and specific refinement of necessary, based upon Tier
sources, pathways, and identify contaminant exposure pathways and 2 findings and site-specific
receptors sources and receptors human and ecological data collections
receptors
Work Plan Establish Work Plan to fill Develop Work Plan to Develop Work Plan to Develop Work Plan to
data gaps with existing conduct the screening collect data (for example, collect additional site-
information assessment and perform porosity) to perform for specific data, including
simple mathematical example relatively community or habitat
modeling (EQP/Narcosis, simplistic predictive models structure and function;
Biotic Ligand, etc.), and an that are often algebraic population modeling
assessment of uncertainty and employ semi- (probabilistic); population
analytical expressions; or community level effects;
bioavailability testing in site- specific or chemical-
sediments (passive specific benchmarks;
sampling, AVS/SEM, bioavailability factors;
porewater sampling, etc.), tissue data or other
and uncertainty measures of
assessment bioaccumulation and
biomagnification; toxicity
testing, quantitative
measures of uncertainty
Stakeholders Identify appropriate Identify, define their Identify, define their Identify, define their
stake
...