The ailing U.S. coal industry is about to get another black mark. Alpha Natural Resources Inc. is expected to file for chapter 11 bankruptcy protection early Monday to cut its more than $3 billion debt load, according to people familiar with the matter, as a severe slump in coal prices continues to wreak havoc on the industry. The Bristol, Va., company, one of the largest U.S. coal producers, hasn’t completed the terms of a restructuring plan but will likely sell some of its best mines or turn them over to creditors and close others during its trip through bankruptcy court, the people said. Alpha has secured as much as $600 million in bankruptcy financing from senior lenders and secured bondholders to fund its operations during its chapter 11 case, some of the people said. A steep drop in coal prices has Alpha and its rivals bleeding cash and choking […]