The objectives of this research are to determine the nature, magnitude, and time dependence of the major and trace element releases as functions of the raw shale mineralogy, retorting conditions, and spent shale mineral assemblages. These experimental studies will focus on retorting variable regimes characteristic of most retorting processes. As an adjunct objective, the relation of laboratory results to those obtained from both bench-scale and pilot-scale retorts, when both have been operated under similar retorting conditions, will be defined. The goal is to develop a predictive capability for spent shale chemistry as a function of the raw material feedstock and process parameters. Key accomplishments follow: completed an overview of health, environmental effects, and potential ''show stoppers'' in oil shale development; elucidated the importance of both raw material and process in the identity and behavior of spent shale wastes (Occidental raw and spent shales from the Logan Wash site); completed a balanced factorial design experiment to investigate the influence of shale type, temperature, and atmosphere on spent shale behavior; compared the behavior of spent shales from laboratory experiments with shales generated from MIS retorting by OOSI at Logan Wash, Colorado; completed a study of the partitioning of minerals, inorganics, and organics as a function of particle size in a raw shale from Anvil Points, Colorado; evaluated the application of the Los Alamos nuclear microprobe to the characterization of trace element residences in shale materials; established the use of chemometrics as a major tool for evaluating large data bases in oil shale research and for relating field and laboratory results; conceptualized and evaluated experimentally a multistaged leaching control for abandonment of underground retorts; and coordinated activities with other DOE laboratories, industry laboratories, and universities. 13 refs., 1 fig., 2 tabs.
