Guidance for Conducting Risk Assessments and Related Risk ...

4. RISKASSESSMENT IMPLEMENTATION
Risk assessments and risk-related activities undertaken in support of the U.S. Department of Energy,
Oak Ridge Operations (DOE-ORO) follow the regulatory guidance documents listed in Table 5, the
technical memoranda listed in Appendix A, and “site-specific” guidance. Generally, the “site-specific”
guidance presented in the following subsections has been developed to:
• address the use of existing/historical data;
• incorporate land use determinations;
• define the use of screening and integration point assessments;
• select scenarios, pathways, chemicals, and media of concern; and
• identify risk assessment tools available for use by all subcontract personnel.
A risk assessment consists of four distinct steps: data collection and evaluation, exposure assessment,
toxicity assessment, and risk characterization. The outcome of a risk assessment is either a set of
chemicals, pathways, media, and/or scenarios of concern for which an appropriate action must be
undertaken or a determination that no action is required. The following sections briefly describe the steps
of a risk assessment and define the “site-specific” guidance related to each step.
Table 5. Risk assessment regulatory guidance documents
Appendix D of Risk Assessment Guidance for Superfund, Vol. 1, (“Corrections to RAGS—Part B, Sections 3.3.1
and 3.3.2”). (EPA 1991d)
Dermal Exposure Assessment: Principles and Application, Interim Report. EPA/600/8-91/011B, Office of Research
and Development, Washington, D.C. (EPA 1992)
Exposure Factors Handbook, Volume I, II, and III, EPA/600/P-95/002Fa, Office of Research and Development,
National Center for Environmental Assessment, Washington, D.C. (EPA 1997)
Guidance for Data Usability in Risk Assessment, EPA/540/G-90/008, Office of Emergency and Remedial Response,
Washington, D.C. (EPA 1990)
Risk Assessment Guidance for Superfund: Volume 1, Human Health Evaluation Manual (Part A), EPA/540/1-
89/002, Office of Emergency and Remedial Response, Washington, D.C. (EPA 1989)
Risk Assessment Guidance for Superfund: Volume 1, Human Health Evaluation Manual (Part B, Development of
Risk-based Preliminary Remediation Goals), OSWER Directive 9285.7-01B, Office of Emergency and
Remedial Response, Washington, D.C. (EPA 1991a)
Risk Assessment Guidance for Superfund: Volume 1, Human Health Evaluation Manual (Part C, Risk Evaluation of
Remedial Alternatives), OSWER Directive 9285.7-01C, Office of Emergency and Remedial Response,
Washington, D.C. (EPA 1991b)
Risk Assessment Guidance for Superfund: Volume 1, Human Health Evaluation Manual (Part D, Standardized
Planning, Reporting, and Review of Superfund Risk Assessments), OSWER Directive 9285.7-01D, Office of
Emergency and Remedial Response, Washington, D.C. (EPA 1998)
Standard Default Factors, OSWER Directive 9285.6-03, Office of Emergency and Remedial Response,
Washington, D.C. (EPA 1991c)
Supplemental Guidance to RAGS: Region 4 Bulletins, Human Health Risk Assessment, Waste Management
Division, Office of Technical Services. (EPA 1996)
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