For nearly 40 years, the Rocky Flats site, located about 16 miles northwest of downtown Denver, served as a nuclear weapons production facility, and it now bears the scars of that role. Soil, groundwater, and surface water at the site, as well as many of the buildings, are contaminated with radioactive materials, such as plutonium and uranium; toxic metals, such as beryllium; and hazardous chemicals, such as cleaning solvents and degreasers. Accordingly, the site is now one of the Department’s priorities for environmental cleanup. While most of the approximately 6,300 acres that make up the Rocky Flats site served through the years as an undeveloped buffer zone, about one-half of a square mile (385 acres) in the center of the site constituted the industrial area, where, for decades, plutonium was recycled and shaped into pits for use in nuclear weapons. About three-fourths of the site’s more than 800 original structures (buildings, guard towers, storage tanks) were not radiologically or chemically contaminated by site operations over the years, but the remainder were—some severely so. This was the case, for example, for seven building complexes that housed the plutonium-processing operations. The cleanup and closure of Rocky Flats is a complex, tedious, and labor- intensive undertaking. Because plutonium-contaminated materials must be specially contained and carefully handled, the work is hard and slow. Plutonium is dangerous to human health, even in minute quantities, especially if inhaled. Workers dealing with plutonium-contaminated materials and equipment must wear cumbersome protective suits with enclosed respiratory systems and sometimes must wield heavy and ungainly tools. The equipment being worked on must also be enclosed within plastic or glass to prevent airborne contaminants from reaching unprotected workers or surfaces. Figure 1 shows workers in protective clothing dealing with contaminated materials. Within DOE, the Office of Environmental Management is responsible for cleaning up the Department’s nuclear weapons complex and closing down facilities, including Rocky Flats, that are no longer needed for producing nuclear weapons. At the Rocky Flats Field Office, approximately 190 DOE employees oversee the contractor’s activities. In July 1995, Kaiser-Hill was awarded a 5-year contract to begin cleaning up Rocky Flats. When we reported in April 1999 on the status of the cleanup project, Kaiser-Hill’s target date to close Rocky Flats was 2010. In response to a 1996 DOE initiative to close as many sites as possible by 2006, DOE entered into negotiations with Kaiser-Hill that resulted in the current closure contract, which took effect February 1, 2000. Kaiser-Hill manages the cleanup work, which is done predominantly by subcontractors. As required by the contract, Kaiser-Hill has developed a closure project baseline, which serves as its detailed management plan for the project. The closure contract specifies both Kaiser-Hill’s and DOE’s responsibilities. Kaiser-Hill is responsible for processing, packaging, and shipping off-site all of Rocky Flats’ nuclear materials and radioactive and hazardous wastes; cleaning up and demolishing more than 700 structures that remained on-site in February 2000; and cleaning up the site’s contaminated soil and groundwater. DOE is required to deliver a variety of services and items to support the project. Essentially, the contract requires DOE to arrange receiver sites for all the materials and wastes that must be shipped off-site and to obtain the necessary certifications for the containers in which the materials and wastes must be packed and shipped. Many DOE sites will play a significant role in Rocky Flats’ cleanup and closure, especially those sites that are scheduled to receive materials or wastes from Rocky Flats, such as the Savannah River Site in South Carolina and the Waste Isolation Pilot Plant (WIPP) in New Mexico. The closure contract is structured so that DOE pays all of the cleanup costs plus an incentive fee for Kaiser-Hill’s services. Kaiser-Hill will not receive the majority of this fee until it has finished most of the cleanup and closure tasks, as specified in the contract. Kaiser-Hill will earn a higher incentive fee if it saves on costs and finishes its work before the target completion date. In effect, DOE will share the savings from these lower costs by paying Kaiser-Hill a higher fee. Conversely, if Kaiser-Hill exceeds the contract’s target date and cost, resulting in higher costs to the government, the contractor will earn a lower fee. The contract also requires Kaiser-Hill to comply with the terms of the Rocky Flats Cleanup Agreement, which serves as the regulatory framework for the site’s cleanup and closure. The agreement specifies the roles and responsibilities of DOE and the two primary regulators for Rocky Flats: the Environmental Protection Agency (EPA) and the state of Colorado’s Department of Public Health and Environment. EPA derives its regulatory authority primarily from the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended, commonly known as Superfund. Colorado exercises regulatory authority over hazardous wastes under the Resource Conservation and Recovery Act of 1976, as amended, as well as the Colorado Hazardous Waste Act. Pursuant to the cleanup agreement, EPA has the lead regulatory authority over the cleanup of the site’s buffer zone, while Colorado has the lead authority over the cleanup of the industrial area. The cleanup agreement incorporates the requirements of both Superfund and the Resource Conservation and Recovery Act, and requires that the site’s other stakeholders be consulted during the development of cleanup plans. These other stakeholders include the Defense Nuclear Facilities Safety Board;local governments; community, business, and citizen groups; and individuals. Under the terms of the contract, and as used in this report, “closure” is defined as the point in time at which Kaiser-Hill has completed all of its cleanup tasks, as specified in the contract. When Kaiser-Hill notifies DOE that it has completed its work, DOE has 90 days either to accept the project as complete or to provide a list of items that Kaiser-Hill must address. The contractor will then have 9 months to complete its work on these items. Separate from how “closure” is defined under the contract, however, is the process of removing Rocky Flats from the list of Superfund sites. When DOE and the regulators are satisfied that the cleanup meets all regulatory requirements, and sufficient monitoring information has been gathered on the condition of the air, water, and soil, EPA will have the information it needs to consider removing the site from the Superfund list. After closure has been achieved, however, monitoring and maintenance activities at the site will continue for many decades. Soil and water conditions will continue to be monitored to ensure that contamination remains within acceptable levels. Also, all treatment facilities, such as groundwater treatment systems, will continue to be maintained as long as necessary. DOE’s long-term cost estimates include the costs of monitoring and maintenance activities through 2070, but some of the activities will probably need to go on longer. By the end of fiscal year 2000, Kaiser-Hill had made significant strides in cleaning up the Rocky Flats site, but the vast majority of the work, and some of the most technically challenging, remained. The bulk of the work entails (1) processing, packaging, and shipping various forms of plutonium and uranium; (2) processing, packaging, and shipping radioactive wastes; (3) cleaning up and demolishing buildings and other structures; and (4) remediating contaminated water and soil. The total cleanup cost is estimated to be about $7.5 billion—in constant 2000 dollars—if the site’s closure occurs by December 15, 2006. The project’s total cost will grow, however, if additional work is required or if delays occur. After closure, costs will continue through at least 2070 for activities such as site monitoring and maintenance, and for contractor employee retirement benefits. These long-term costs will be about another $1.4 billion in constant 2000 dollars. Since it began cleanup operations in fiscal year 1996, the contractor has made considerable progress toward closure in several work categories. Progress has been greatest in two areas: shipping nuclear materials and remediating groundwater. In most major areas of work, however, the lion’s share remains to be done. Table 1 shows the status of the four major cleanup activities, at the end of fiscal year 2000. Kaiser-Hill has made significant progress in shipping the site’s special nuclear materials (plutonium and enriched uranium). When Kaiser-Hill began cleanup work under its previous contract (in fiscal year 1996), the site had over 16 metric tons of special nuclear materials, including various forms of plutonium (e.g., pits, other metal parts, and oxides) and enriched uranium. The contractor was responsible for stabilizing and packaging all of the special nuclear materials and shipping them off-site, primarily to other DOE sites, such as Oak Ridge (in Tennessee), Pantex (in Texas), and Savannah River (in South Carolina). By the end of fiscal year 2000, the contractor had inventoried the special nuclear materials and had prepared and shipped all of the plutonium pits and most of the highly enriched uranium. The contractor had also shipped some of the 6.6 metric tons of plutonium metals. Kaiser-Hill still has to stabilize, package, and ship off-site the remainder of the plutonium-contaminated highly enriched uranium, the remainder of the plutonium metals, and all 3.2 metric tons of plutonium oxides. According to a DOE official, shipments of plutonium metals began in the spring of 2000; shipments of oxides are expected to begin in June 2001. Kaiser-Hill plans to complete all shipments of metals and oxides by the end of fiscal year 2002. In the sequence of activities necessary to close the site, removal of the special nuclear materials logically precedes many of the other cleanup activities.