The Powder River Regional Coal Team has voted unanimously to approve an extension to Cloud Peak Energy's Spring Creek Coal Mine north of Sheridan.
The Billings Gazette reports the coal lease was unanimously approved by the board, which is comprised of local and federal officials.
Experts estimate the mine still holds 198 million tons of coal, which could keep the mine running for another 16 years. Cloud Peak hopes to begin mining from the new lease area by 2024.
The next step in securing the lease is a public review process.