A federal watchdog says it will review the U.S. Environmental Protection Agency's efforts to clean up abandoned uranium sites on the Navajo Nation.
The EPA received funding in 2015 from a $1 billion settlement to address 50 sites in northeastern Arizona. The sites were run by Kerr McGee Corp., later acquired by Anadarko Petroleum Corp.
The EPA's Office of Inspector General says it wants to determine whether the EPA is prioritizing sites that present the greatest threats. Reviews generally take 18 months.
Mining in the Cove area of the reservation began in 1949 and ended in the late 1960s. The EPA and Dine College have found high concentrations of uranium in the soil and groundwater.
The EPA has installed warning signs at unregulated water wells.