DENVER — The U.S. Attorney’s Office won’t prosecute an employee of the Environmental Protection Agency over the massive mine wastewater spill that turned the Animas River a shade of yellow.

The EPA’s Office of Inspector General said it found evidence the employee might have violated the Clean Water Act and given false statements.

But prosecutors declined to pursue the case and instead will be sent to senior EPA management for its review.

A cleanup led by the EPA at the Gold King mine above Silverton triggered the spill on Aug. 5, 2015.  The 3 million-gallon blowout sent water laced with toxic heavy metals through southwest Colorado, New Mexico and Utah.

The EPA has taken responsibility for the spill and given millions of dollars to the area to help it recover.

Three House Republicans slammed the Justice Department for not pursuing charges.

“By not taking up the case, the Department of Justice looks like it is going easy on its colleagues in EPA,” House Natural Resources Committee Chairman Rob Bishop, R-Utah, Oversight Committee Chairman Jason Chaffetz, R-Utah, and oversight subcommittee on interior Chairwoman Cynthia Lummis, R-Wyo., wrote in a letter to the Justice Department.

The Navajo Nation is suing the EPA for what it sees as negligence in cleaning up the disaster.