Naturally occurring uranium in groundwater in northeastern Washington State

This presentation is intended to provide background on naturally occurring uranium in groundwater, describe the risks it poses, explore key data and results, and provide well owners, teachers, community members, and public health officials with information on what steps can be taken to mitigate this risk. The presentation is informed by a U.S. Geological Survey (USGS) preliminary assessment of uranium concentrations in groundwater in northeastern Washington State (Kahle and others, 2018, A geologic map of northeastern Washington State shows the widespread presence of intrusive igneous rocks (pinks and reds). The map shows uranium assay sites and mines, indicating that uranium has been found in the region in high enough concentrations to economically extract. This map of Washington State shows potential exposure to radon in air, based on the presence of uranium-bearing rocks or sediment. The high (red) and moderately high (orange) hazard classifications found in northeastern Washington State show the geologic potential for elevated uranium levels since radon is a daughter product of uranium decay.