UMWA Local 1924 and the surface mine confirmed the deal on Tuesday, but did not indicate details or specific effective dates for it. The UMWA did not return a request for more details.

“The agreement has provisions that will allow for efficiency improvements and includes wage increases and enhancements for a variety of benefit programs,” the producer said.

About 98% of Kayenta’s 400- plus workforce is native American.

The complex operated by Peabody Western Coal supplies fuel to the Navajo Generating Station in Page, just kilometres from the Grand Canyon, resulting in more than $117 million in annual direct economic benefits for tribal communities.

The mine operates through lease agreements with the Navajo and the Hopi.

Earlier this year, the mine marked 1 million work hours without a lost-time injury.