PROTOTYPE SDSS FOR USING PROBABILITY ANALYSIS IN SOIL CONTAMINATION

The purpose of this study is to demonstrate the benefits of applying s patial decision support system (SDSS) methodologies for assessing soil contamination problems. A nonparametric geostatistical technique, ind icator kriging (IK), was used to determine the probability distributio ns for characterizing the uncertainty in the unsampled area. Such dist ributions over a contaminated site allow mapping of block maps of the probability above some maximum allowable limit, estimate the risks of decisions, and provide information for remediation assessment. Geograp hical information systems offer spatial analysis and data management c apabilities that can benefit IK analysis. A prototype system, PASCA (P robability Analysis for Soil Contamination Assessment), was developed for this study. It utilizes a menu-driven interface to combine the Tai wan geographical database and models for IK analysis. PASCA was design ed to specially aid users in preliminary screening of remediation prio rities and in designating contaminated soil blocks that need additiona l sampling. The application of PASCA is analyzed through a case study involving the heavy metal cadmium.