• Number of sites characterized by progress through the major phases of remediation from site discovery to site closure, as outlined in Table 1-1,
• Principal chemicals of concern, and
• Status of “closed” sites with respect to the potential presence of residual contamination.
At a national level, information was gathered from the U.S. Environmental Protection Agency (EPA) for sites that fall under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Resource Conservation and Recovery Act (RCRA), or Underground Storage Tank (UST) programs using publicly available databases and via conversations with EPA program officers. Department of Defense (DoD) sites were explored with the aid of the online Annual Reports to Congress and via conversations with DoD staff. Information from the Department of Energy (DOE) and other federal agencies was collected from published literature. Another large group of sites includes those that fall under state purview, such as state Superfund, voluntary cleanup programs, Brownfields, and some dry cleaning sites. Information about such sites was gathered from a variety of sources, including state websites and databases, third-party websites, published literature, and conversations with state program managers.
The numbers in this chapter reflect the Committee’s best efforts to compile available data on the magnitude of the problem, but there is significant uncertainty associated with some of the data. First, some of the reported data reflect detailed analyses (e.g., DoD, CERCLA, RCRA) while other data are only estimates. Second, there are differences in accounting across the programs that make it difficult to assess the magnitude of the hazardous waste problem on a consistent basis. In particular, CERCLA and RCRA’s best available data are for facilities that could and often do contain many individual contaminated sites. To make matters even more confusing, the term “site” is used by the CERCLA and RCRA programs to mean an entire facility, while other programs use the term “site” to represent an individual contaminant release within a larger facility. In this report the term “site” refers to an individual area of contamination within a facility; to avoid confusion, the term “Superfund site” is not used when referring to a facility on the Superfund list. Finally, the statement of task requests information on the numbers of sites that have yet to reach “site closure”—a term that is defined differently by each of the large federal cleanup programs as well as by state agencies.
Considering these sources of uncertainty (estimates vs. real data, summing of facilities and individual sites, and the varying definitions of site closure), the overall total should be considered as a rough idea of the magnitude of the problem. Though it can be argued that there is limited