The ecology of technological risk in a Sunbelt city

In this paper we examine the spatial distributions of four types of technological hazards in the Phoenix, Arizona, metropolitan area. The focus is on the locations of hazardous industrial and toxic waste sites in relation to the demographic composition of adjacent neighborhoods. Our interest is to determine whether hazardous sites, including industrial facilities in the EPA's Toxic Release Inventory, Large Quantity Generators of hazardous wastes, Treatment, Storage, and Disposal Facilities, and federally identified contamination sites, are disproportionately located in areas with lower income and minority residents. We examine patterns of environmental inequity in Phoenix, a sprawling Sunbelt city with a growing post-Fordist industrial sector. First, using 1996 EPA data for four types of technological hazards, and 1995 Special Census data for Maricopa County, we employ a GIS to map the spatial distributions of hazardous sites and to analyze the demographic characteristics of census tracts with and without point-source hazards. A second methodology is used to produce a cumulative hazard density index for census tracts, based on the number of hazard zones-one-mile-radius circles around each facility-that overlay each tract. Both methodologies disclose clear patterns of social inequities in the distribution of technological hazards. The cumulative hazard density index provides a spatially sensitive methodology that reveals the disproportionate distribution of risk burdens in urban census tracts. The findings point to a consistent pattern of environmental injustice by class and race across a range of technological hazards in the Phoenix metropolitan region.