CASPER, Wyo. (AP) — A landowners group is suing the state of Wyoming for declining to prove that $27 million in ranchland used as collateral for a coal mine's cleanup is really worth that much money.

The dispute concerns Blackjewel LLC, which announced that it had acquired Eagle Butte and Belle Ayr mines from Contura Energy in December 2017.

But in order to take full operation of those mines, Blackjewel has to provide financial assurances to cover the cost of mine cleanup.

Of the $247 million in cleanup liability at the two mines, $26.7 million is covered by ranchland in Campbell County.

The Powder River Basin Resource Council argues in its lawsuit that the ranch isn't worth that much.

The Wyoming Attorney General's Office declined comment.

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