be useful to anyone involved in the cleanup of contaminated sites. The report contains reviews of regulations applicable to contaminated sites, the state of the art in remediation technology development, and obstacles to technology development that apply well beyond sites in the DOE weapons complex.

Within DOE, the Subsurface Contaminants Focus Area (SCFA) in the Office of Science and Technology is responsible for developing technologies to clean up metals, radionuclides, and DNAPLs in groundwater and soil. SCFA, like others involved in developing technologies to solve these problems, has encountered major obstacles. This report recommends where SCFA should direct its technology development program to achieve the most progress.

This report was prepared by the National Research Council's (NRC's) Committee on Technologies for Cleanup of Subsurface Contaminants in the DOE Weapons Complex. The NRC appointed this committee in 1997 at DOE's request. The committee included experts in hydrogeology, environmental engineering, geochemistry, soil science, and public health. Members were selected from academia, consulting firms, private industries, and public interest groups to represent a range of perspectives on DOE contamination problems. The committee's conclusions are based on a review of relevant technical literature, briefings by staff from DOE and environmental regulatory agencies, visits to several DOE installations, consultations with other experts, and the knowledge and experiences of committee members.

In total, DOE is responsible for cleanup of 113 installations in 30 states. To date, DOE has identified approximately 10,000 individual contaminant release sites within these installations that contain groundwater and/or soil contamination; continuing investigations may uncover further contamination. Current estimates indicate that some 1.8 × 10⁹ m³ of groundwater and 75 × 10⁶ m³ of soil are affected. These contamination problems date from the start in 1942 of the Manhattan Project to develop nuclear weapons.

Assessing DOE's progress in cleaning up contaminated groundwater and soil is difficult because of data limitations, conflicting terminology, and lack of an agreed-upon metric for measuring success (see Chapter 1 for details). DOE's Office of Environmental Restoration reported that, as of 1998, remedies had been selected for 27 of 92 active groundwater cleanup projects and for 163 of 221 soil cleanup projects. Some of these projects include multiple contaminated sites,

Front Matter (R1-R15)

Executive Summary (1-14)

1 Introducution: DOE's Groundwater and Soil Contamination Problem (15-38)

2 The Changing Regulatory Environment (39-71)

3 Metal and Radionuclides: Technologies for Characterization, Remediation, and Containment (72-128)

4 DNAPLs: Technologies for Characterization, Remediation, and Containment (129-201)

5 DOE Remediation Technology Development: Past Experience and Future Directions (202-239)

6 Findings and Recommendations (240-250)

Appendix A Facilities at which DOE is Responsible for Environmental Cleanup (251-263)

Appendix B SCFA Technology Deployment Report (264-268)

Appendix C Biographical Sketches of Committee Members and Staff (269-273)

Appendix D Acronyms (274-276)

Index (277-285)