Water Sampling Results in the Navajo Nation
EPA is investigating if and to what extent abandoned uranium mines (AUMs) on the Navajo Nation have impacted groundwater and surface water.
EPA and the Navajo Nation agreed to assess potential impacts on water resources at four types of AUMs: surface mines, underground “dry” mines above groundwater, underground “wet” mines below groundwater, and “leach” mines where acid was used on site to extract ore.
To better understand potentially impacted water resources, in 2016 the United States and the Navajo Nation agreed to complete studies of two AUMs to determine if groundwater or surface waters have been affected by those mines.
Subsequently, in 2022 the U.S. and Navajo Nation agreed that these two water studies will be carried out under the newly created Phase 2 Expanded Trust Agreement (pdf) by the Phase 2 Expanded Trust (More information on the Phase 2 Expanded Trust can be found at Trust Mines). To this end, detailed surface water and groundwater studies are being conducted at Claim 28 mine in the Tachee-Blue Gap chapter and the Saytah/George Simpson 1 Incline mine in the Tolikan chapter by the Phase 2 Trustee, Derrith Watchman-Moore.
Separately, EPA is conducting a study to investigate potential impacts to surface water and groundwater from underground mines at the Northeast Church Rock/Quivira mining complex in the Church Rock chapter.
Finally, EPA will conduct a comprehensive investigation of potential impacts to surface water and groundwater in the Cove chapter as part of the Lukachukai Mountain Mining District remedial investigation and feasibility study.
Though these studies are ongoing, they are helping EPA to better understand the potential impacts to groundwater and surface water and to ensure that cleanup options implemented at abandoned uranium mine sites are protective of surface water and groundwater.
The following documents provide more information about EPA's work to provide safe drinking water to communities affected by uranium contamination.