The site selection process for nuclear power stations encompasses a broad range of considerations. A categorization of these considerations consistent with the needs of the U.S. Atomic Energy Commission, as the regulatory agency, and of the utility company involves these major areas of concern. They are issues related to safety, environmental impact, and engineering/economics. The more important environmental considerations and their measuring parameters presented in this paper include biota, ecological systems and water quality, land use, aesthetics, water availability, and meteorology.