Modern federal environmental law has a built-in dynamic of tension that since its inception has led to challenging relations between the U.S. Environmental Protection Agency (EPA) and the states. On the one hand, the U.S. Congress enacted numerous environmental statutes in the early 1970s because of widespread dissatisfaction with state efforts to protect the environment. Congress made EPA ultimately accountable for achieving the mandates of federal law. On the other hand, Congress contemplated that states would actually implement and enforce the requirements of these statutes, subject to federal oversight. To a large extent, its vision has been realized; states now administer over 75% of the major federal delegable environmental programs,¹ and conduct the great majority of environmental enforcement in this country. But as Prof. David Hodas notes, "heavy reliance on state enforcement is a double-edged sword. When we 'deputize' the states to implement national environmental laws, we shift the government's discretionary enforcement power to state and local officials, who may not be interested in, or able to carry out, federal goals."²

The tension characterizing the federal/state enforcement relationship has, if anything, intensified in recent years, particularly during the 1990s. Many state programs have grown and become more professional over the past two or three decades. With this maturation, state agencies are increasingly feeling their oats. They have become dissatisfied with a role that they perceive as EPA "dependents" or "subordinates," and increasingly insist on changing the terms of this relationship to one of "partners." With the emergence in the 1990s of the Environmental Council of States (ECOS), the influential lobbying group representing the environmental commissioners of 51 of the 55 states and territories, in particular, state environmental agencies enjoy a new level of influence in Washington, D.C. State calls for devolving more environmental authority have met with sympathetic receptions in both Congress and the executive branch.