Horizontal Diffusion, Vertical Diffusion, and Internal Pressure in State Environmental Policymaking,

Throughout the 1980s, states developed policies to address the growing problem of abandoned and uncontrolled hazardouswaste sites. Not surprisingly, some states have adopted stringent policies that are similar to the federal Superfund program, whereas others have developed different approaches. In this article, we develop and test empirically a model of the strength of state hazardouswaste programs, which we depict as a function of both internal determinants and external diffusion. For internal determinant explanations we consider the effects of problem severity, internal political factors, interest group pressure, and socioeconomic and demographic variables. We also include variables representing regional and top-down (national) diffusion. Our results indicate the importance of both internal determinants and external diffusion. Strong state hazardous waste programs are a function of state wealth and the severity of internal hazardous waste problems, as well as external determinants, with regional diffusion as a particularly influential factor.