OF-24-08 Baseline Radiological Study Year 3: Uravan Belt

The Colorado Geological Survey (CGS), a department of the Colorado School of Mines, has been funded through a grant from the Colorado Department of Public Health & Environment (CDPHE) to conduct a 5-year study of baseline naturally occurring radionuclides and metals in groundwater obtained from privately owned residential water wells throughout Colorado. This report presents the methodology and results of Year 3 conducted in 2024 in the Uravan Belt region of western Colorado, including parts of Mesa, Montrose, and San Miguel counties. Digital PDF download. OF-24-08D

For additional information, please see OF-24-13, a similar study conducted in the San Luis Valley in south-central Colorado.

From the report:

The Uravan Belt consists of a narrow, elongated 70 by 30 miles geological area in western Colorado and eastern Utah which contains uranium, vanadium, and radium ore deposits. These deposits were mined historically from the Jurassic aged Salt Wash Member of the Morrison Formation. In the eastern portion of San Miguel County, uranium was mined as a by-product with vanadium in the mineral roscoelite in the Jurassic Entrada Sandstone near the town of Placerville. In Colorado, the Uravan Belt includes the currently inactive Gateway, Uravan, Bull Canyon, Gypsum Valley, and Slick Rock mining districts containing about 1,200 small mines¹. The Uravan mineral belt mines produced almost fourteen million tons of ore averaging 0.24 percent triuranium octoxide (U₃O₈) and over 356 million pounds of vanadium oxide². The population in this region is mostly concentrated within small former mining towns extending from Gateway through Uravan (a former town) to Slick Rock. Even though the population is generally restricted to small towns, this region was selected for Year 3 of this study based on the widespread deposits of uranium (Figure 1).