Uniform standards are much favored among the makers of federal environmental policy in the United States, which is to say, among the members of Congress. By and large-judging at least from the legislation it has enacted-Congress expects the air and water eventually to meet the same minimum levels of quality in every state in the country, and expects each pollution source in any industrial category or subcategory to be controlled just as much as every other such source, notwithstanding the source's location or other peculiar characteristics. There are exceptions to these generalizations, but they are exceptions and not the rule.1 Since 1970, environmental policy in the United States increasingly has been federal (meaning that standards and controls are, for the most part, imposed by the national government, although they generally are implemented at the state and local levels). And, nominally at least, the federal policy has been one of uniform standards and controls in the sense suggested above. The standards have been set in ways essentially indifferent to territorial and, to some considerable degree, source variation. In thinking about federal uniform environmental standards, I shall focus for the most part on the pollution problem, to the exclusion of other environmental problems having to do with such concerns as vanishing species, land reclamation, or the regulation of toxic waste sites. Air and water pollution controls are my general subject, and air pollution controls my chief case in point. This is partly a matter of convenience, a way to get to the bottom of some fundamental considerations that display themselves in superficially disparate ways across the vast reaches of federal environmental legislation. Mostly, though, my focus reflects the reality that federal pollution policy, and air pollution policy in particular, is especially plagued by the vices of uniformity. In any event, what I have to say about the case of pollution policy can be applied to other environmental policies to the extent (probably considerable) that the arguments in the one case fit the situations in the other cases. I narrow my focus-though again not its bearing-in another way as well. The discussion thus far has alluded to two different kinds of pollution standards: (1) ambient quality standards that limit the amount of pollution permitted in any state's air or water, and (2) emission or effluent standards that in one way or another limit the amount of pollution that can come from sources in any state (cars, factories, power plants, and the like). Both types of standards are aimed at controlling pollution, but there is nevertheless a difference between them that impels me to be concerned, here, primarily with the first category, ambient quality standards. My topic is environmental policy in a federal system, and it is with its ambient controls that the federal government specifies the obligations of the various states with respect to water or air quality. Ambient standards dictate, at a minimum, how clean the environmental media (in this case water, and particularly, air) in a given area must be. Any area may choose to clean up more if it wishes.2 In short, ambient standards directly limit what the states, not pollution sources, are free to do. Hence they are the immediately interesting subject from the standpoint of federalism.3
Krier, James E. "On the Topology of Uniform Environmental Standards in a Federal System and Why it Matters (Symposium: Environmental Federalism)." Md. L. Rev. 54, no. 4 (1995): 1226-41.