Peabody Energy, one of Wyoming’s largest coal producers, appears to be teetering on the brink of bankruptcy.

According to the company’s latest filings with the Securities and Exchange Commission, some of Peabody’s senior lenders are pushing for the company to pursue “in-court restructuring.” Peabody writes in the filings that it is seeking alternatives to a bankruptcy declaration.

The push comes at a bad time for Peabody though, as it faces potential defaults on several loans. In 2015, Peabody agreed to sell mines in Colorado and New Mexico to Bowie Resources for $358 million. But as Bloomberg reported in February, the deal appears to have hit a snag. If the mine sale falls through, Peabody notes in its filings that it may be unable to comply with the terms of several loan agreements.

If Peabody were to declare bankruptcy, it wouldn’t be the first of Wyoming’s major coal companies to do so—Arch Coal and Alpha Natural Resources have also filed for Chapter 11 bankruptcy in the last year. Both are hoping to restructure and emerge from bankruptcy later this year.