[en] An environmental monitoring program that included the sampling and analysis of air, water, and soil on and off the plant site was conducted. Particulate samples were collected from air samplers that operated continuously at the plant perimeter and in 12 communities located near the plant. An analysis of these samples indicated that the concentrations of airborne plutonium at perimeter and community locations were identical and were within the range attributed primarily to fallout from atmospheric nuclear weapons testing. The sanitary water was processed through a tertiary treatment facility before discharge, and the discharges were monitored for compliance with the Plant's National Pollutant Discharge Elimination System (NPDES) permit. Violations of NPDES daily limits occurred on nine occasions and were related to fluoride, pH, suspended solids, and biochemical oxygen demand. In all cases, the causes for these violations were identified and corrective actions taken. The plutonium, uranium, americium, and tritium radioactivity concentrations measured in Great Western Reservoir and Standley Lake during 1978 all were found to be less than 0.07% of the applicable DOE Radioactivity Concentration Guides. Drinking water from nine communities was monitored for plutonium, uranium, and americium. An assessment was made of the potential Plant contribution to public radiation dose. Total dose to the population living within 80 kilometers was calculated using the community radiation dose values