Possible mechanisms for bioeenvironmental contact of aqueous effluents derived from in situ oil shale processing include accidental, episodic exposure resulting from failure of a containment, leakage during transfer or treatment processes, or contamination and subsurface migration of ground waters to a surface outlet. The magnitude of plant responses and phytotoxic effects resulting from such exposure has not been but needs to be quantified for purposes of risk assessment. The development of control technologies for aqueous effluents looks forward to the potential of using suitably treated process waters for land reclamation purposes. A research project to address plant and process water relationships has been developed. The initial objectives of the project are to: (1) develop quantitative, short-term, cost-effective, diagnostic screening procedures for vegetation; (2) using such procedures, to quantitate the response of selected plants to process waters derived from in situ oil shale processing; (3) provide information for developing control technology. Results meeting the first-stated objective are presented. Two screening procedures, a seed germination assay and growth and development response assays, have been developed using an in situ oil shale process water. (ERB)