1. Introduction. The Hanford site. Environmental awareness. References. 2. Historical Influences on Hanford Operations. Genesis of the Hanford Site. Milestones. Organizations on the Hanford site, early 1980's. References. 3. Operation Areas and Land use at Hanford Original Site Layout. Site layout and activities today. Water quality considerations. References. 4. Operation of the Single-Purpose Reactors, 1943 to 1971. Operational features. Background radiation. Areas of concern. Dilution capacity of the Columbia river. References. 5. University of Washington Studies, 1943 to 1960. Studies with X-radiation. Studies with cobalt -60 gamma rays. Significance of the university effort. References. 6. Setting for Bioenvironmental Studies in the Hanford Reach, 1945 to 1971. Opportunities. Facilities. Personnel. Artificial radioactivity. Role of advisory groups. References. 7. Reactor Effluent Monitoring, 1945 to 1971. Monitoring reactor effluent with fish. Chemical effects during monitoring. Temperature effects during monitoring. Radioactivity effects during monitoring. Significance of effluent environmental monitoring studies. References. 8. Field Studies with Radioactivity in Hanford Reach, 1945 to 1971. Radionuclide releases - early studies (1941-1962). Radionuclide releases - later studies (1961-1971). Transport and behavior of radionuclides downstream from Hanford. Radioactivity in ecosystem after reactor closures. Significance of field studies with radioactivity. References. 9. Laboratory Studies with Radioactivity and Aquatic Organisms, 1945 to 1971. Direct exposure of organisms to radio-nuclides. Uptake and transfer of radionuclides in microcosms. Significance of laboratory studies with radioactivity. References. 10. Thermal Effects Studies in the Hanford Reach, 1960 to 1971. Field studies: thermal releases to the Columbia river. Laboratory studies: lethal, sublethal, and physiological effects of temperature. Investigations with the fish pathogen Columnaris. Ecological functions in the Hanford reach. Significance of thermal studies in the Hanford reach. References. 11. Generic Studies at Hanford after Closure of the Single-Purpose Reactors, 1971 to 1981. Studies with radioactivity after reactor closure. Thermal effect studies with aquatic biota. Combined effect studies involving temperature. Effects of hydroelectric generation. Site characterization studies. Significance of generic studies at Hanford, 1971 to 1981. References. 12. Facility-Specific Studies in Hanford Reach after Closure of Single-Purpose Reactors, 1971 to 1984. Hanford generating project. N reactor. Washington public power supply system. Nuclear plant No. 2 (WNP-2). Biological data from 1970's assessments. Significance of facility-specific studies at Hanford, 1971 to 1984. References. Index.