Alpha disagrees with LQD's assessment and continues to believe it has fully complied with the regulations and is currently reviewing all options to reverse or rectify the LQD judgment, Alpha chief financial and strategy officer Philip Cavatoni said.

“Alpha and its affiliates take very seriously our obligation to operate in an environmentally responsible and fiscally sound manner,” he said.

“We also appreciate the firm but fair approach with which the Wyoming Department of Environmental Quality has managed its self-bonding program in the past, which is why the limited transparency in this current process is concerning.

“While we wait for further clarification from the LQD regarding its review methodology and process, we are investigating a range of options to address this new determination.”

In each annual self-bond renewal process, Alpha has determined its compliance status by consistently following a methodology prescribed by state regulations, and it has shared these calculations with the LQD as a part of each renewal application, according to the company.

The LQD has never previously commented on Alpha’s calculation methodology.

At the request of the LQD, Alpha also recently provided supplemental fiscal information to the division for its review.

However, despite repeated attempts to gain clarity from the LQD regarding any changes the division has made in interpreting these regulations, numerous questions remain unanswered that Alpha believes should have been addressed prior to any determination being made.

According to the LQD’s notification, Alpha now has 90 days to provide substitute bonding.

Alpha estimates that self-bonding by coal companies currently operating in Wyoming totals approximately $US2 billion, of which Alpha's share is just over $400 million.

According to the Wyoming Mining Association, Wyoming is home to 9 of the top 10 producing mines in the nation and coal production provides the state's second largest source of tax revenue for state and local governments.