Planning and Scoping

This is the stage in the Ecological Risk Assessment process where it is determined what the extent of the problem is likely to be. The scope of US EPA risk assessments describes what is currently known about the environmental risk at a particular site that will (or can) be analyzed. The scope is defined according to who or what is at risk of adverse effects from identifiable sources and stressors through several routes of exposure over varied time frames.

Documents

1. Role of BTAGs in Ecological Assessment (PDF) (4 pp, 364 K) September 1991 Eco Update
   This EcoUpdate bulletin describes the responsibilities and activities of the Biological Technical Assistance Group: a group of scientists established to aid remedial project managers.
2. Briefing the BTAG: Initial Description of Setting, History and Ecology of a Site (PDF) (11 pp, 289 K) Eco Update August 1992
   This EcoUpdate bulletin focuses on the first meeting between a Remedial Project Manager and the Biological Technical Assistance Group, during which there is an initial exchange of information and guidance.
3. Cumulative Risk Assessment Program
   This guidance directs each office to take into account cumulative risk issues in scoping and planning major risk assessments and to consider a broader scope that integrates multiple sources, effects, pathways, stressors and populations for cumulative risk analyses in all cases for which relevant data are available.
4. Developing a Scope of Work for Ecological Assessments (PDF) (13 pp, 100 K) Eco Update, May 1992
   This EcoUpdate bulletin helps Remedial Project Managers to plan and manage ecological assessments as part of the Remedial Investigation/Feasibility process.
5. Ecological Assessment of Superfund Sites: An Overview (PDF) (8 pp, 67 K) Eco Update, December 1991
   This EcoUpdate bulletin describes the components of the ecological risk assessment process and how they fit into the Remedial Investigation/Feasibility Study process.
6. Ecological Risk Assessment and Risk Management Principles for Superfund Sites, (Issuance of Final Guidance), October 7, 1999
   Guidance intended to help Superfund project managers to make ecological assessment decisions that are consistent across the United States and are transparent to the public.
7. Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessments - Interim Final June 1997, EPA 540-R-97-006
   These proposed guidelines are EPA's first Agency-Wide Ecological Risk Assessment Guidelines. They are broad in scope, providing general principles and providing numerous examples to show how ecological risk assessment can be applied to a wide range of systems, stressors, and biological spatial/temporal scales.
8. ECO Update Bulletin Series
   EcoUpdates are a series of bulletins which provide information on various aspects of Ecological Risk Assessments, including toxicity testing, the role of the Biological Technical Assistance Group (BTAG), field studies, and screening level risk assessments.
9. Guidance for Data Usability in Risk Assessment (Part A), April 1992
   Guidance for Data Usability in Risk Assessment, Part A, is designed to provide data users with a nationally consistent basis for making decisions about the minimum quality and quantity of environmental analytical data that are sufficient to support Superfund risk assessment decisions, regardless of which parties conduct the investigation. Part B of this guidance addresses radioanalytical issues.
10. Guidance for Data Usability in Risk Assessment (Part B), May 1992
    This document is the second part of the two-part Guidance for Data Usability in Risk Assessment. Part B provides supplemental guidance to Part A on planning and assessing radioanalytical data needs for the baseline human health risk assessment conducted as part of the remedial investigation process at sites containing radioactive substances. Part B is not a stand alone document and at all times should be used in conjunction with Part A.
11. Guidance for Data Usability in Risk Assessment: Quick Reference Fact Sheet, September 1990
    Bibliography of entries from categories of EPA documents.
12. Guidelines for Characterizing Background Chemicals in Soil at Superfund Sites, September 2002
    This document provides guidance to the U.S. Environmental Protection Agency Regions concerning how the Agency intends to exercise its discretion in implementing one aspect of the CERCLA remedy selection process. The guidance is designed to implement national policy on these issues.
13. Role of Background in the CERCLA Cleanup Program, April 26, 2002
    This document clarifies the U.S. Environmental Protection Agency (EPA) preferred approach for the consideration of background constituent concentrations of hazardous substances, pollutants, and contaminants in certain steps of the remedy selection process, such as risk assessment and risk management, at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or "Superfund") sites.
14. Supplemental Guidance to RAGS: Calculating the Concentration Term (PDF) Exit(8pp, 67 K)
15. Guidelines for Ecological Risk Assessment
    These Agency-wide guidelines are provided to improve the quality and consistency of EPA's ecological risk assessments. The Guidelines expand on and replace the 1992 report Framework for Ecological Risk Assessment.
16. National Recommended Ambient Water Quality Criteria
    The criteria in this document (for 158 pollutants) provide guidance for states and tribes authorized to establish water quality standards under the Clean Water Act to protect human health and aquatic life.
17. (Revised) Policy on Performance of Risk Assessments During RI/FSs Conducted by PRPs 
    As part of the recently announced administrative reforms to the Superfund program, the Administrator stated that EPA would reaffirm its commitment to "allow PRP's to conduct risk assessments under proper circumstances as part of the overall site study (RI/FS)." This memorandum announces EPA's revised policy on allowing PRP's to conduct the risk assessment portion of the RI/FS.
18. Ecological Soil Screening Level (Eco-SSL) Guidance and Documents
    EPA's Superfund program has just issued ecological soil screening levels (Eco-SSLs) for thirteen contaminants that are frequently found in soil at Superfund sites.
19. Role of Screening Level Risk Assessment and Refining COCs (Chemicals or Contaminants of Concern) in Baseline Ecological Risk Assessment, 2001
    This EcoUpdate bulletin describes the process and purpose of the screening level ecological risk assessment, which is the first steps in a ecological risk assessment at a site, and how the list of COCs can be refined to include only those contaminants that may pose a risk.
20. Role of the Ecological Risk Assessment in the Baseline Risk Assessment, OSWER Directive 9285.7-17, dated August 12, 1994
    Describes the process and purpose of baseline ecological risk assessments, which, if required, come after screening level risk assessments.
21. Screening Level Ecological Risk Assessment Protocol 1999
    This is a guidance document that describes the process used in conducting ecological risk assessments at Hazardous Waste Combustion Facilities.
22. Selecting and Using Reference Information in Superfund ERAs 1994 (PDF) (6 pp, 2.4 MB)
23. The Role of Natural Resource Trustees in the Superfund Process (PDF) (10 pp, 192 K) March 1992 Eco Update
    This EcoUpdate bulletin is intended to help project managers to work with Natural Resource Trustees, explaining the responsibilities and authorities of those trustees and those of the Remedial Project Managers and On-Scene Coordinators with respect to those trustees.

Problem Formulation

An initial step of an Ecological Risk Assessment (ERA) is to decide which components of an ecosystem (the sum of all the living organisms and the physical factors in a particular area) should be protected: in other words, what species should be the focus of the ERA. This initial step is part of Problem Formulation, which includes the development of a conceptual model: a representation of how the particular contaminants at a site are expected to behave in the environment.

The conceptual model is based on fate (e.g., does a contaminant break down in the environment or is it persistent?) and transport (how does a contaminant move through the environment and where does it end out?). The purpose of the problem formulation and the conceptual model is used to narrow attention to the animals and/or plants likely to be exposed to the contaminants at the site. In risk assessment language, the species that may be exposed to contaminants are called "receptors".

The following people should be involved in the problem formulation process: On-scene Coordinators (OSCs), Remedial Project Managers (RPMs), Natural Resources Trustees, contractors, and Risk Assessors (RAs). For this step, the risk assessor gathers information about the site that can help determine the potential risk to plants and animals found at the site being studied. Information can come from a variety of sources, including a site visit, historical information, and data from previous sampling of the area. The following issues should be addressed:

1. Environmental setting;
2. Contaminants known or suspected to be at the site;
3. Contaminant movement physically within the site and through the local food chain;
4. What plants and animals may be harmed by contaminants at the site;
5. How the plants or animals come in contact with the contaminants;
6. What are the effects on the plants and animals that are exposed.

Documents

1. Ecological Assessment of Superfund Sites: An Overview, Eco Update, December 1991
   This EcoUpdate bulletin describes the components of the ecological risk assessment process and how they fit into the Remedial Investigation/Feasibility Study process.
    
2. Ecological Risk Assessment and Risk Management Principles for Superfund Sites, (Issuance of Final Guidance), October 7, 1999
   Guidance intended to help Superfund project managers to make ecological assessment decisions that are consistent across the United States and are transparent to the public.
    
3. Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessments - Interim Final, June 1997, EPA 540-R-97-006
   This document provides guidance on how to design and conduct consistent and technically defensible ecological risk assessments for the Superfund program.
    
4. ECO Update Bulletin Series
   EcoUpdates are a series of bulletins which provide information on various aspects of Ecological Risk Assessments, including toxicity testing, the role of the Biological Technical Assistance Group (BTAG), field studies, and screening level risk assessments.
    
5. Guidelines for Ecological Risk Assessment
   These Agency-wide guidelines are provided to improve the quality and consistency of EPA's ecological risk assessments. The Guidelines expand on and replace the 1992 report Framework for Ecological Risk Assessment.
    
6. Role of Screening Level ERAs and Refining Contaminants of Concern in Baseline Ecological Risk Assessments
   This EcoUpdate bulletin describes the process and purpose of the screening level ecological risk assessment, which is the first steps in a ecological risk assessment at a site, and how the list of COCs can be refined to include only those contaminants that may pose a risk.
    
7. Role of the Ecological Risk Assessment in the Baseline Risk Assessment, OSWER Directive 9285.7-17, August 12, 1994
   Describes the process and purpose of baseline ecological risk assessments, which, if required, come after screening level risk assessments.
    
8. Screening Level Ecological Risk Assessment Protocol, 1999
   This is a guidance document that describes the process used in conducting ecological risk assessments at Hazardous Waste Combustion Facilities.

Top of Page

EPA Links

1. EPA Region 5 Ecology Technical Center Ecological Risk Assessment
   Overview of ecological risk assessment process in Superfund, regional case studies, toxicity profiles, and regional contacts.
    
2. Greenbook Pesticide Labels and MSDS, EPA's Pesticide Program, PPIS Data, Biopesticides, and RED Pesticide Summaries
   EPA pesticide news stories, summaries, and featured sites.
    
3. SW-846, Test Methods for Evaluating Solid Waste, Physical/Chemical Methods
   SW-846 contains over 200 documents, including the Table of Contents, Disclaimer, Preface, Chapters One through Thirteen, and many different methods for the sampling and analysis of wastes. All of the documents found in the Third Edition of SW-846, as updated by Updates I, II, IIA, IIB, III and IIIA, are located at this site.

Top of Page

External Links

1. ATSDR's Toxicological Profiles
   Link to information on toxicological effects caused by hazardous chemicals found at National Priorities List site.
    
2. DEQ Information
   Link to U.S. Fish & Wildlife Service's Division of Environmental Quality.
    
3. DOE Standard, A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota (PDF) (48 pp, 374 K)
   and the RAD-BCG Calculator
   Link to Department of Energy’s procedure for investigating radiation exposure to aquatic and land plants and animals.
    
4. EC Info and Literature From Region 2 EC Program
   Link to U.S. Fish & Wildlife Service's Environmental Contaminants program.
    
5. Guidelines for Interpretation of Residues in Biota, Water, and Sediments from USGS-BRD
   National Irrigation Water Quality Program, Department of the Interior
    
6. National Pesticide Information Center (NPIC) Exit
   A cooperative effort of Oregon State University and the U.S. Environmental Protection Agency (800-858-7378).
    
7. Oak Ridge National Laboratory: Toxicology and Risk Analysis Section
   The Risk Information Web Server is part of the Toxicology and Risk Analysis Section, in the Life Sciences Division, at the Oak Ridge National Laboratory (ORNL). Page lists several information resources.
    
8. Oak Ridge National Laboratory - Ecological Risk Analysis: Tools and Applications
   Link to guidance, screening benchmarks for various categories of plants and wildlife, and examples of completed ecological risk assessments.
    
9. PCB Review by Heidi Fieldler Exit
   A general overview of Polychlorinated Biphenyls (PCBs).
    
10. TOXNET (including TRI), Extoxnet and Extoxnet-pesticides Exit
    Provides a variety of information about pesticides.
     
11. USDA Pesticide Info Exit
    Each fact sheet (issued by the U.S. Dept. of Agriculture Forest Service) provides information on forest and land management uses, environmental and human health effects, and safety precautions for various pesticides and their formulations.
     
12. USGS - Contaminant Reviews
    Contains the 35 reports in the Contaminant Hazard Reviews (CHR) originally published between 1985 and 1999 in the U.S. Dept. of the Interior Biological Report series, which include information on selected inorganic and organic chemicals and ionizing radiation.
     
13. USGS Acute Toxicity Database
    This database summarizes the results from aquatic acute toxicity tests conducted by the USGS Columbia Environmental Research Center located in Columbia, Missouri. The acute toxicity test provides a relative starting point for hazard assessment of contaminants and is required for federal chemical registration programs.

Top of Page

Stressor Response and Exposure Analysis

Calculation of Stressor Response and Exposure Estimates is the quantitative (statistical) determination of what plants and animals are exposed and to what degree they are exposed and if that level of exposure is likely or not to cause harmful ecological effects.

The calculations of risk and estimated exposure involve the calculation of hazard quotients (the ratio of chemical contaminant concentration to a selected screening benchmark) for the former; and, for the latter, the use of various parameters (area use, food ingestion rates, bioaccumulation rates, bioavailability, life-stage, body weight, and dietary composition) to determine the levels of exposure to a chemical contaminant by a selected plant or animal (receptor).

Documents

1. ECO Update Bulletin Series
   EcoUpdates are a series of bulletins which provide information on various aspects of Ecological Risk Assessments, including toxicity testing, the role of the Biological Technical Assistance Group (BTAG), field studies, and screening level risk assessments.
    
2. Guidelines for Ecological Risk Assessment
   These Agency-wide guidelines are provided to improve the quality and consistency of EPA's ecological risk assessments. The Guidelines expand on and replace the 1992 report Framework for Ecological Risk Assessment.
    
3. Ecological Soil Screening Level (Eco-SSL) Guidance and Documents
   EPA's Superfund program has just issued ecological soil screening levels (Eco-SSLs) for thirteen contaminants that are frequently found in soil at Superfund sites.
    
4. Peer Review Workshop Report on Ecological Soil Screening Levels, Eco Update, (Guidance document dated August 31, 2000.)
   This document is a summary of the Peer Review Workshop on Ecological Soil Screening Levels.
    
5. Region 5 RCRA Corrective Action Ecological Data Quality Levels
   These are concentration levels that can be used in screening level ecological risk assessments.
    
6. Using Toxicity Tests in Ecological Risk Assessment, Eco Update, March 1994
   An EcoUpdate Bulletin that describes the purpose and process of toxicity testing in ecological risk assessments.
    
7. Non-Dioxin-Like PCBs: Effects and Consideration In Ecological Risk Assessment
    
8. Memorandum: Response To Ecological Risk Assessment Forum Request For Information On the Benefits of PCB Congener-Specific Analyses
    
9. Assessing Risks to Populations at Superfund and RCRA Sites Characterizing Effects on Populations 
    
10. Wildlife Exposure Factors Handbook December 1993, EPA/600/R-93/187
    The bulk of this document summarizes literature information on exposure factors for wildlife, including homerange sizes, food and water intake rates, types of food consumed, body weights, etc.

Top of Page

EPA Links

1. ECOTOX Database System
   The ECOTOX (ECOTOXicology) database provides single chemical toxicity information for aquatic and terrestrial life. ECOTOX is a useful tool for examining impacts of chemicals on the environment.
    
2. Ecotox Thresholds (software, released by Jan 1996 Eco Update, EPA 540/F-95/038
   Web site containing information on EPA's Ecotox Thresholds, which are benchmark values for chemicals commonly found in surface water, sediments, and soil.
    
3. Ecological Risk Assessment
   Website with information on ecological risk assessment.
    
4. EPA Region 4 Supplements to RAGS
   Information on regional risk assessment (human health and ecological) as well as regional contacts and screening values.
    
5. EPA Region 5 Ecology Technical Center Ecological Risk Assessment
   Overview of ecological risk assessment process in Superfund, regional case studies, toxicity profiles, and regional contacts.

Top of Page

External Links

1. Biological and Ecotoxicological Characteristics of Terrestrial Vertebrates from Barnett Rattner
   Summary information in the database includes species, collection date, site coordinates, estuary name, hydrologic unit catalog code, sample matrix, contaminant concentrations, biomarker and bioindicator responses, and reference source.
    
2. BSAF Database from WES
   Information on Biota-to-Sediment Accumulation Factors and lipids from the Army Corps of Engineers.
    
3. Canadian National Guidelines and Standards Exit
   Web site source for Canada's benchmark screening values for surface water, sediment, soil, and tissue.
    
4. DOE Standard, A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota (PDF) (48 pp, 374 K)
   and the RAD-BCG Calculator
   Link to Department of Energy’s procedure for investigating radiation exposure to aquatic and land plants and animals.
    
5. Guidelines for Interpretation of Residues in Biota, Water, and Sediments from USGS-BRD
   National Irrigation Water Quality Program, U.S. Department of the Interior.
    
6. NOAA Screening Quick Reference Tables
   NOAA has developed a set of Screening Quick Reference Tables, or Squirts, that present screening concentrations for inorganic and organic contaminants in various environmental media (water, sediment, and soil). The Squirts also include guidelines for preserving samples and analytical technique options.
    
7. Oak Ridge National Laboratory: Toxicology and Risk Analysis Section
   This EcoUpdate bulletin describes the components of the ecological risk assessment process and how they fit into the Remedial Investigation/Feasibility Study process.
    
8. Oak Ridge National Laboratory - Ecological Risk Analysis: Tools and Applications
   Link to guidance, screening benchmarks for various categories of plants and wildlife, and examples of completed ecological risk assessments.
    
9. Preliminary Remediation Goals for Ecological Endpoints (PDF) (41 pp, 140 K)
   Preliminary Remediation Goals are upper concentration limits of specific chemicals that are expected to be protective of human health or the environment and are useful in risk assessment and decision making at Superfund sites.
    
10. Spatial Analysis and Decision Assistant Exit
    A software (freeware) tool designed to aid in ecological risk assessments with a spatial component.
     
11. USACE Environmental Residue Effects Database
    A compilation of data, taken from the literature, where biological effects (e.g., reduced survival, growth, etc.) and tissue contaminant concentrations were simultaneously measured in the same organism.
     
12. USGS Acute Toxicity Database
    This database summarizes the results from aquatic acute toxicity tests conducted by the USGS Columbia Environmental Research Center located in Columbia, Missouri. The acute toxicity test provides a relative starting point for hazard assessment of contaminants and is required for federal chemical registration programs.
     
13. USGS - Contaminant Reviews
    Contains the 35 reports in the Contaminant Hazard Reviews (CHR) originally published between 1985 and 1999 in the U.S. Dept. of the Interior Biological Report series, which include information on selected inorganic and organic chemicals and ionizing radiation.
     
14. USGS Upper Miss/IL Sediment Database
    Contains sediment-contaminant data (44 data sets from a total of 3950 analyzed sediment samples collected from 1974 through 2000 from the Upper Mississippi and Illinois Rivers and their tributaries) of known quality in a readily accessible format.
     
15. Wildlife Exposure and Toxicity Factors for California Wildlife (searchable) Exit
    A compilation of exposure factors (i.e., ecological and physiological data) and toxicity data for a number of California mammals, birds, amphibians and reptiles.

Top of Page

Risk Characterization

Risk Characterization is the analysis and integration of information gathered during the risk assessment process into a summary and description of the data and risks associated with the site.

Documents

1. EPA Guiding Principles on Monte Carlo Analysis
2. EPA's Science Policy Council web page on Risk Characterization
3. EPA's 1992 Guidance on Risk Characterization
4. EPA Risk Characterization Program
5. Risk Characterization Memo - Implementing the Administrator's Risk Characterization Memorandum
6. Risk Assessment Guidance for Superfund (RAGS) Part A: Risk Characterization (PDF)(22 pp, 912 K)
7. Risk Assessment Guidance for Superfund (RAGS) Part A: Risk Characterization Exhibits (PDF)(9 pp, 1.5 MB)
8. Superfund guidance (RAGS Volume III)

Top of Page

EPA Links

No EPA links available

Top of Page

External Links

Spatial Analysis and Decision Assistance Exit
Spatial Analysis and Decision Assistance is a freeware program developed at the University of Tennessee with funding from EPA, NRC, and DOE that provides comprehensive risk assessment tools in a spatial modeling environment. Risk assessors can use SADA to perform traditional risk assessment PRG calculations, PRG screens, and forward human health calculations for one or more contaminants. Users have complete control over all toxicological data, physical properties, and landuse/pathway exposure parameters to create site specific risk assessments. In addition, the risk models are integrated with SADA's spatial analysis tools, decision frameworks,and sample design strategies allowing users drive a risk based characterization from a preliminary initial sample design through a final feasibility study. In addition, SADA allows users to import their own site or region specific screening or decision threshold values separately from SADA's own risk modeling tools.

Top of Page