A Navajo Nation utility has been fined $25,000 for discharging more pollutants into a waterway than its permit allowed.
The fine was announced Tuesday by the U.S. Environmental Protection Agency and its counterpart on the Navajo Nation.
Under settlements with the agencies, the Navajo Tribal Utility Authority must bring its Window Rock treatment plant into full compliance by the end of the year. The utility also agreed to build new infrastructure for the treatment plant.
The EPA said an inspection revealed that the tribal utility had been sending too many pollutants into the Black Creek, a tributary of the Puerco River, since at least 2011. The tribe's Water Quality program brought an enforcement action.
The treatment plant serves more than 13,000 people in Apache County on the reservation.