11.1. During recent years, an assessment of environmental effects has been a necessary part of every major construction activity in the United States. In many cases, the achievement of a balance between the benefits of the activity and the impact on the environment has resulted in contro­versy. Therefore, before considering nuclear power effects, it is helpful to examine what is meant by environmental “contamination” and the effects of fossil-fueled energy sources.

11.2. Although the terms contamination and pollution are synonymous in many dictionaries, there is a distinction from the environmental view­point. By contamination, we merely mean the introduction of a foreign or “unnatural” substance, while pollution is a stronger term describing a level of contamination that is harmful, such as smog from automobile exhaust systems. However, the picture becomes complicated when we consider the introduction of natural substances, which can be harmful. For example, volcanic eruptions have released large quantities of particulate matter and

radioactivity into the atmosphere. Natural springs sometimes contain un­pleasant and harmful sulfur compounds. Natural background radiation levels vary from place to place as a result of the influence of cosmic radiation at higher altitudes and the proximity to minerals such as granite containing radioisotopes. Therefore, one must view the introduction of foreign sub­stances into the environment as undesirable only if harmful effects result compared with the impact of “everyday” natural events.

11.3. Environmental considerations apply to many sectors of our in­dustrialized society, particularly where materials are processed. Effluents from metal smelters, chemical plants, and petroleum refineries must be controlled, for example. The reduction of pollutants from motor vehicles is a continuing challenge. Similarly, energy production is a vital component of this society. Nuclear and fossil fuels are our primary energy resources. Therefore, it is only fair to view the environmental impact of nuclear power plants in comparison with the impact of the other option, fossil-fueled plants.