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Center for Land Use Interpretation, Grand Junction/Climax Uranium Mill Disposal Cell, 17 May 2012, CLUI Land Use Database


Grand Junction Disposal Site

The former 114-acre Grand Junction processing site, historically known as the Climax Uranium Mill, was a uranium refining facility that produced 2.2 million tons of milled ore from 1950 to 1970. Radioactive mill tailings left at the site were sold and transported throughout the region for widespread, extensive construction use as aggregate or fill. From the early 1950s to 1966, approximately 300,000 tons of uranium tailings from the mill were used for concrete or mortar at more than 4,000 construction projects throughout the region, including houses, schools, commercial buildings, sidewalks, an airfield, a power plant, and a shopping mall. 

In 1972, after tailings were found to be radioactive, the Atomic Energy Commission provided federal aid to the State of Colorado to decommission all public materials constructed using Climax’s byproducts in the worst case of uranium tailing mismanagement. Following the mill’s closure in 1970, Climax Uranium Company demolished 8 of the 12 main mill buildings at the processing site, decontaminated equipment to be sold, and buried what couldn’t be decontaminated inside the tailings pile. Construction of a more stable disposal site began in 1990 approximately 18 miles southeast of Grand Junction. Over the next four years, 4.4 million cubic yards of contaminated processing site materials and radioactive waste were transported to the cell for storage and burial. 

In 1998, DOE declared cleanup complete under the Uranium Mill Tailings Remedial Action Project, but the disposal cell remains open through 2023 or until filled. The former mill site is being redeveloped into a waterfront park called Las Colonias, named after the Latino community historically displaced by the mill. 


Carr, Jonathan and Claire Kempa. "The History of Las Colonias Park: Historic Crossroads Along the Riverfront of Grand Junction, Colorado." Prepared for the City of Grand Junction Parks and Recreation Department. April 2015. Accessed June 11, 2021.

Center for Land Use Interpretation. "Grand Junction Climax Uranium Mill Site, Colorado." clui.org. Accessed July 31, 2020.

Grammer, Elisa J. “Uranium Mill Tailings Radiation Control Act of 1978 and NRC’s Agreement State Program.” Natural Resources 13, no. 3 (1981): 469–522.


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