OVERVIEW OF A DECISION SUPPORT SYSTEM FOR THE EVALUATION OF LANDFILL COVER DESIGNS

Authors: Paige, Virginia; Stone, Jeffry; Lane, Leonard; Yakowitz, Diana

Submitted to: Multiple Objective Decision Support Systems for Land, Water, and Environment
Publication Type: Proceedings
Publication Acceptance Date: 9/28/1996
Publication Date: N/A
Citation: N/A

Interpretive Summary: An overview of the prototype decision support system (PDSS) for evaluating landfill cover designs is presented. The need for a PDSS as a tool to aid risk managers in evaluating landfill covers is discussed. The components of the PDSS, simulation models, the decision model, and the graphical user interface are described, as well as the methodology for evaluating alternative cover designs. The objectives in developing the PDSS are presented, and the current status of the PDSS is described. The PDSS has been evaluated using field data from a landfill cover demonstration. The simulation models have been calibrated and tested and the long-term stability of the models have been evaluated. New data sets are needed in order to conduct a full validation of the PDSS and all of its components.

Technical Abstract: The primary purpose of the U.S. Department of Energy (DOE) Environmental Restoration Program is to manage the health and ecological risks associated with intentional and accidental releases of radioactive and hazardous contaminants to the environment. At DOE sites where health and ecological risks are considered to be low based on preliminary baseline risk assessment studies, regulatory requirements for final closure of old landfills can often be met using a well designed trench cap to isolate the buried waste. The selection of the "best" design among feasible alternatives requires consideration of multiple and often conflicting objectives. A computer based decision support system (DSS) is being developed to assist the risk manager in selecting an appropriate trench cap design for shallow land waste disposal sites. The DSS components include: simulation models, a decision model, and a graphical user interface. The methodology used in the selection process consists of selecting and parameterizing decision variables or criteria, selecting feasible trench cap design alternatives, ordering the decision variables and ranking the design alternatives. The results are displayed both as text and graphics, allowing the user to easily evaluate the alternative covers. This approach significantly reduces user subjectivity and bias inherent in most decision making methodologies.