The development and use of a GIS-based expert system for hazardous waste landfill siting

An expert system approach is used to develop an automated hazardous waste landfill siting system for use in the State of Indiana. Siting experts across Indiana and the United States were surveyed, using a questionnaire to identify critical criteria for use in a siting algorithm. This algorithm consists of two phases: (1) a hierarchical phase, based on state and federal regulations, and (2) a weighted parameter phase, based on weighted averages of the results of the expert survey. Disparate data sets needed for implementing the siting algorithm were collected for Tippecanoe County, Indiana. The accuracy and integrity of the primary data sets were assessed and their utility verified at an appropriate scale. The application of soils, geological, geophysical, climatic, hydrological and cultural data sets from Tippecanoe County, to the siting algorithm produced a map which shows optimum sites for siting a hazardous waste landfill. Sensitivity analysis of the data sets and the siting criteria indicated the siting protocol is robust. Sensitivity analysis then was used to determine the effect of changing conditions on selected sites. This analysis showed that many possible sites would be suitable even under changing climatologic conditions based on global warming and cooling scenarios