The Navajo Nation has submitted a claim of more than $160 million in damages to the federal government over last year's mine waste spill that fouled rivers in three western states.
A cleanup team led by the U.S. Environmental Protection Agency triggered the August 2015 spill while working at the Gold King Mine near Silverton, Colorado.
The 3-million-gallon blowout tainted rivers in Colorado, New Mexico and Utah with tons of toxic heavy metals including arsenic, mercury and lead.
In a letter Monday to the EPA, attorneys say the tribe still awaits more than $3 million in unreimbursed expenses for costs through Sept. 30 to deal with the spill that contaminated the San Juan River.
The tribe also is seeking $159 million for 10 years of health monitoring and other assessments.