Comparison of DOE's Recently Developed Risk Prioritization Model With Other Priority-Setting Tools Used for Ranking Hazardous Waste Sites. E. M. Faustman, G. van Belle, T. G. Ewers, J. A. Moore, C. Powers, M. Greenberg, and G. S. Omenn, University of Washington, Department of Environmental Health, 4225 Roosevelt Way NE, Seattle, WA 98105; Institute for Evaluating Health Risks, Suite 608, 1101 Vermont Avenue, NW Washington, DC 20005; Resources for Resp Management, 575 Boylston St., Boston, MA 02116; EOHSI, 681 Frelinghuysen Rd., Piscataway, NJ 08855
The increasing awareness of the extent and complexity of hazardous waste sites and the realization of limited resources has necessitated the development of prioritization systems for ranking the remedial activities at those sites. Federal and state departments, with jurisdiction over different sites, have developed various ranking schemes for prioritizing the management of their respective sites. The National Research Council, in a 1994 report, compares and contrasts the major prioritization models currently used by federal and state departments including EPA's Hazard Ranking System (HRS), DOD's Defense Priority Model (DPM), DOE's Multimedia Environmental Pollutant Assessment System (MEPAS), and DOE's Environmental Restoration Priority System (ERPS). In this report we extend the NRC review to include DOE's Risk Prioritization Model (RPM). The RPM utilizes a three dimensional qualitative risk matrix which integrates the severity of impact in six key categories and the likelihood of the occurrence of an adverse event with environmental management characterization and remedial activities. Each activity is described in a risk data sheet. The six categories considered in this model include three health based categories: public safety and health, site personnel safety and health and environmental protection (ecological health). Other categories incorporated into this model include: compliance, mission impact and cost effective risk management. Each category is ranked on a scale of severity of impact (SOI) as well as likelihood of occurrence (LOC). For example, for the category on health the four SOI categories are A) catastrophic injuries or illness (including death, permanent total disability, chronic or irreversible illnesses or gross overexposures); B) critical injuries or illnesses (including disabilities that are partial but permanent and/or temporary complete disability, and overexposures that are serious); C) marginal injuries or illness, (illnesses or disabilities of short duration or slight over exposures); and D) negligible illnesses or injuries (injuries/illnesses that do not require hospitalization and exposures below 20% of limits). LOC categories are: very high (probability of expectation, POE = 1 for 1 year), high (POE<1.0, ·0.1), medium (POE ,0.1, ·0.01) and low (POE <0.01). In this qualitative risk matrix the categories are not weighted against each other. Our primary focus in comparing the various models was to examine how risks to human and environmental health are integrated and weighted. For example, human health and environmental risks are considered in all the models mentioned except MEPAS, in which only human health risks were evaluated. Socioeconomic risks are evaluated only in ERPS and RPM. An important aspect of comparisons between the models is examining the factors involved in the evaluation of the risks. We examine and compare how human, environmental and socioeconomic risks are evaluated between the different models. This presentation will highlight examples of the different model applications.
Work supported by the Consortium for Risk Evaluation with Stakeholder Participation.