RESEARCH Environmental Priority-Setting Through Comparative Risk Assessment DAVID LEWIS FELDMAN* Energy, Environment, and Resources Center Department of Political Science, and Graduate Program in Environmental Policy The University of Tennessee Knoxville, Tennessee 37966, USA RUTH ANNE HANAHAN RALPH PERHAC Energy, Environment, and Resources Center The University of Tennessee Knoxville, Tennessee 36966, USA ABSTRACT / More than three dozen states and communities in the United States have undertaken comparative risk projects to establish environmental priorities and, thus, to address their most important environmental problems. This trend has been supported by a growing consensus among subnational governments that they are increasingly encum- bered with prescriptive, top-down environmental regulations and policies without regard to the policies’ efficacy, benefit, or cost. Despite the rising use of comparative risk projects, few studies have systematically analyzed and compared them. The purpose of our research was to fill this void. We examined key elements of comparative risk projects includ- ing how they were administered; how they involved the pub- lic; how they characterized, ranked, and prioritized risks; whether and how they implemented ranking results; and whether and how they evaluated project results. The re- search team reviewed project reports and independent studies and undertook a survey of risk project participants. Results showed that while many priority-setting projects have successfully identified environmental problems and characterized and ranked their risks, few have developed risk-management strategies. Successes to date include in- creasing environmental awareness among participants; building consensus and establishing collaboration among diverse stakeholders; and establishing novel means of pub- lic involvement. However, no project that we evaluated has, as yet, documented achievement of a system for developing and implementing environmental priorities in order to miti- gate their most significant environmental problems. Further, it may be difficult to know if and when this objective is met unless projects establish mechanisms for evaluating their results, a project element that was often missing or limited in scope. We also discuss the challenges to developing imple- mentable risk-management strategies and conclude by cit- ing future research needs. Responsibility for managing environmental prob- lems in the United States has increasinglyfallen to states and communities. With EPA’s encouragement and sup- port, more than three dozen states and communities have turned to comparative risk projects to establish environmental priorities (US GAO 1995, Clinton and Gore 1995, NAPA 1995, Minard 1996, Jones 1996). This EPA encouragement has taken two principal forms. First, EPA has urged states to ‘‘find ways to involve the public in the process of setting environmental priori- ties’’ (US EPA 1990). Second, the agency has imple- mented a small grantsprogram (approximately$50,000) to help states and communities undertake comparative risk assessments to rank environmental risks and set priorities. Encouragement of comparative risk assessment partly stems from internal politics within EPA. The agency’s own Science Advisory Board (SAB) has for some time been prodding it to incorporate public ‘‘information that supports the technical analysis of risk’’ and to encourage ‘‘a substantial (public) voice in establishing risk reduction priorities’’ (US EPA 1990). SAB’s hope has been that such encouragement will lessen the gap between the expert’s and layperson’s perceptions of serious environmental risks. Comparative risk projects typically compare and ultimatelyrank environmental threatsbyweighing their relative probabilitiesand magnitudesofharm to human health, ecosystem health, and quality of life (NAS 1996a, US EPA1993, Davies 1994). In addition, compara- tive risk projects at the subnational level are unique in that they incorporate the values and concerns of the public in the risk-ranking process. This trend toward using comparative risk assess- ments to set priorities has been bolstered byan emerg- ing consensus that local and state governments are too KEY WORDS: Comparative risk assessment; Environmental priori- ties; Risk-ranking *Author to whom correspondence should be addressed. Environmental Management Vol. 23, No. 4, pp. 483–493  1999 Springer-Verlag New York Inc.