WASHINGTON — Aquila Inc. has filed an involuntary Chapter 11 petition against Price-based C.W. Mining Co. in an effort to collect a $24.8 million judgment it won against the coal mining company owned by the polygamous Kingston family.

The involuntary petition filed Tuesday in the U.S. Bankruptcy Court in Salt Lake City alleges that C.W. Mining isn't paying its debts as they become due.

In late October, a federal judge ordered C.W. Mining, also known as Co-Op Mining Co., to pay nearly $25 million to Aquila for failing to deliver on a contract for hundreds of thousands of tons of coal.

Aquila of Kansas City, Mo., a distributor of electricity and natural gas in North America, received word from C.W. Mining in 2005 that it wanted out of its contract to supply coal because of labor and production issues.

Filing the involuntary petition against the company, Aquila is seeking to recover the litigation award and interest.