The Petrotomics Mill site (Site) includes historic mine features within several watersheds north of Medicine Bow, Wyoming where Tronox once operated. The Site is located in rural Carbon County. The Site is at an elevation of about 7,100 feet. The primary land uses in the surrounding vicinity are livestock grazing, wildlife habitat, and mineral exploration with numerous reclaimed open pit mines located in the immediate area. The Site makes up part of the Shirley Basin South Disposal site, which is regulated under the Uranium Mill Tailings Radiation Control Act.
Petrotomics Company operated the uranium mill from 1962 to 1974, and again from 1978 to 1985. The mill used a conventional acid leach process to extract uranium from the ore. The milling process created radioactive tailings, a predominately sandy material. Tailings and process solution were conveyed in a slurry to an on-site tailings impoundment. Because of a depressed uranium market, mining and milling operations shut down in 1985 and mill decommissioning began. Petrotomics Company completed encapsulation of the tailings impoundment, contaminated site soil, and contaminated building materials in an engineered, on-site disposal cell in 2000. Site remediation was completed in 2001.
