Evaluation of EPA's Hazard Ranking System

This paper analyzes and evaluates the EPA's hazard ranking system for uncontrolled hazardous waste sites. Two hypothetical sites were developed from several actual case studies for use in the analysis. Sensitivity analyses were performed to determine the system response to route characteristics, containment conditions, waste characteristics and quantity, and location of the facility, under conditions with and without the release of chemical constituents. It was found that use of the ranking system requires considerable information about the facility, its surroundings, waste characteristics, and the geological character of the area. The system provides an expedient format for site evaluation, although it may sacrifice some accuracy in failing to account for the varying meteorological, hydrological, and environmental conditions across geographical regions. When an observed release is evidenced in the air route, the system responds poorly to extremely varied site conditions. The system appears to heavily weight the protection of population with less emphasis toward the protection of natural resources such as critical habitat or national parks.