Other Environmental Concerns
The last chapter was concerned with calculating an economically efficient level of control for several of the important and most common pollutants of air and water. Effective control of those pollutants cannot assure a clean and safe environment, however. Other, often more complex, factors may have a larger impact on environmental quality than the mass pollutants. Ideally, one should perform the same kind of benefit-cost analysis for every residual, separately and in combination, but the huge body of data necessary for such detailed analysis does not exist and will not exist in the near future. It is clear, however, that in spite of our ignorance, there are many environmental issues that must be resolved in the next fifty years because the consequences of ignoring them could be serious. This chapter will describe the present state of knowledge about the more critical of these issues and, where possible, will characterize their scale, severity, reversibility, and cost of control.
Future actions to alleviate burdens on the environment should concentrate on the most critical problems, but the number and variety of environmental threats seem to be unlimited. It is possible to classify these issues in several useful ways. The geographic extent of an environmental disturbance affects our perception of its severity. The effects of the pollutants discussed in chapter 7 usually are limited to individual watersheds or airsheds, but some other problems, notably climate modification, will have international or global effects. The duration of environmental impacts also ranges widely, from a few minutes for noise pollution from airplanes to the many thousands of years for the damaging radiation produced by even brief operation of a nuclear power plant.