stored in four raffinate pits located on the plant property. Uranium processing operations resulted in radiological contamination of the area. Uranium processing operations ceased in 1966, and on December 31, 1967, the AEC returned the facility to the Army for use as a defoliant production plant. The defoliant project was canceled before any process equipment was installed, and the Army transferred of land encompassing the raffinate pits back to the AEC while retaining the Chemical Plant. The AEC, and subsequently the United States Department of Energy (DOE), managed the site, including the Army-owned Chemical Plant, under caretaker status from 1968 through 1985. In 1984, the Army repaired several of the buildings at the Chemical Plant, decontaminated some of the floors, walls, and ceilings, and isolated some equipment. In 1985, the Army transferred full custody of the Chemical Plant to the United States Department of Energy (DOE), at which time the DOE designated control and decontamination of the Chemical Plant, raffinate pits, and Quarry as a major project. The DOE legacy management web site has additional documentation on the status of the site. Weldon Spring Quarry The Weldon Spring Quarry was mined for limestone aggregate used in construction of the ordnance works. The Army also used the quarry for burning wastes from explosives manufacturing and disposal of TNT-contaminated rubble during operation of the ordnance works. These activities resulted in contamination of the soil and groundwater at the quarry. In 1958, the Army transferred the Weldon Spring Quarry to the Atomic Energy Commission, who used it from 1959 to 1966 as a disposal area for uranium, thorium, and radium residues from the Chemical Plant (both drummed and uncontained) and for disposal of contaminated building rubble, process equipment, and soils from demolition of a uranium processing facility in St. Louis. Radiological contamination occurred in the same locations as the nitroaromatic contamination. Weldon Spring Training Area By 1959, with the majority of the site already transferred out of government hands, was redeveloped as for the U.S. Army Reserve as the Weldon Spring Training Area. Superfund sites Weldon Spring Quarry/Plant/Pits (USDOE/Army) site On October 15, 1984, the United States Environmental Protection Agency proposed listing the portions of the Weldon Spring area contaminated with radioactive waste on the National Priorities List. The site was finally listed on July 22, 1987. The Weldon Spring Quarry/Plant/Pits (USDOE/Army) site covers and is located between the Missouri and Mississippi Rivers.