National Priorities List (NPL, US)
The NPL was created in 1980 as part of the Comprehensive Environmental Response and Liability Act or CERCLA (see CERLCA entry in this dictionary). Under CERCLA, the EPA must specify the criteria for establishing priorities for identifying and remediating (the cleanup) of hazardous waste sites.
The US EPA’s NPL page (see first link above) provides information on each site. That information includes a site description that identifies the conditions at the site with respect to the contaminants at the site revealed by testing, the size of the site, its location, an estimate of the number of people affected by the site, and the site’s seriousness score (see below). The NPL site page includes one click mapping of the site as well. There is also a link to the Federal Registry Notice for each site that provides the EPA with authority over such sites.
The EPA examines each proposed NPL beginning with a preliminary investigation. The purpose of the preliminary investigation is to determine if the site require further attention from the EPA, and involves and assessment of the hazards on the site and their potential to create public health harms. Soil, water and air tests are performed to assess toxic threats on site, and geographic analysis is used to assess whether the chemicals on site might leak into waterways or the water table. The EPA provides a score for the site based on the Hazards Ranking System (HRS). Sites that receive a score of 28.5 or higher on the HRS are added to the NPL list. Sites may also be added to the NPL by an action from the Agency for Toxic Substances and Disease Control when it issues a health advisory for a location and recommends that people living near the site be relocated due to the public health harms the site presents.
Following the general procedures above, in 1983 the EPA proposed that the NPL list include 406 sites. In early 2014, there were 1319 officially recognized NPL sites. In total, 375 sites have been cleaned up (remediated) by EPA actions since 1983. Thus, the total number of locations that have been identifies as an NPL site since 1983 is 1,694. Using that figure, since 1983, the EPA has added 1,288 sites to the original 1983 list.
As noted above, sites with an HRS score of 28.5 or higher are added to the NPL list. Given the availability of funds, the EPA takes remedial actions for the site with the highest HRS scores first. Thus, some of the sites of the originally NPL list have yet to be addressed because sites with higher scores have since been identified.
A number of academic studies of NPL sites exist. Some of the questions those studies raise is whether NPL sites are unequally located, that is more likely to be found in poor or minority communities, and whether the cleanup of such sites occurs “fairly” and without any apparent bias. For example, some studies note that abandoned NPL sites in minority neighborhoods take 20% longer to clean up (Brown, 1995; Anderton, Oakes and Egan, 1997). Green criminologists have used NPL data to examine issues of environmental justice and whether such sites are more likely to occur in minority communities (Stretesky and Hogan, 1998).
Anderton, Douglas L., John Michael Oakes, and Karla L. Egan. 1997. “Environmental Equity in Superfund Demographics of the Discovery and Prioritization of Abandoned Toxic Sites.” Evaluation Review 21, 1: 3-26.
Brown, Phil. 1995. “Race, class, and environmental health: a review and systematization of the literature.” Environmental Research 69, 1: 15-30.
Stretesky, Paul, and Michael J. Hogan. 1998. “Environmental justice: An analysis of superfund sites in Florida.” Social Problems 45, 2: 268-287.