CASPER, Wyo. (AP) _ A Virginia-based company that is among the largest coal miners in Wyoming’s Power River Basin has been informed it no longer meets the state’s self-bonding requirements, which could mean it will have to come up with millions in three months to cover clean-up obligations here.

The Casper Star-Tribune ( ) reports that in a statement Friday, Alpha Natural Resources disagreed with the state’s assessment and said it is working to have the decision changed.

Self-bonding status allows a mining company to agree to pay for future clean-up costs associated with its operations without putting down collateral, provided it meets certain financial criteria. Without self-bonding, Alpha would need to post $411 million in 90 days in the form of corporate surety bonds, government securities or cash to keep operating in Wyoming.

Information from : Casper Star Tirbune,