The Mexican Hat tailings site is in the San Juan County, Utah, two road miles southwest of the town of Mexican Hat on the Navajo Reservation. The Navajo community of Halchita is approximately 0.5 mile southwest of the site. The mill at the Mexican Hat site was operated from 1957 to 1965 by Texas-Zinc Minerals Corporation and the Atlas Corporation. Originally, two irregularly shaped tailings piles were located in the northeastern portion of the site. They occupied approximately 69 acres of the 235-acre designated site and contained approximately 2,575,000 cubic yards (cy) of tailings. The total amount of materials, including the tailings and windblown and waterborne materials, is estimated to be 2,810,000 cy.
Uranium Mill Tailings Remedial Action Project Office, Albuquerque Operations Office, Department of Energy, "Remedial Action Plan for the Codisposal and Stabilization of the Monument Valley and Mexican Hat Uranium Mill Tailings at Mexican Hat, Utah" (1993). All U.S. Government Documents (Utah Regional Depository). Paper 14.