The hits just keep on coming for the U.S. coal industry.

Murray Energy Corp. last week said it had notified 4,400 of its 5,300 workers in six states about possible layoffs in September.

St. Clairsville, Ohio-based Murray – which calls itself the largest privately owned coal company in the U.S. – said it will continue to sell and ship coal after any layoffs.

The notices “are due to the ongoing destruction of the United States coal industry by President Barack Obama, and his supporters, and the increased utilization of natural gas to generate electricity,” Murray said in a statement.

When Murray purchased Consolidation Coal Co. from Consol Energy Inc. in December 2013 it also acquired 23 towboats and more than 600 barges, which it now operates as Murray American Transportation Inc. and Murray American River Towing Inc. Asked about the impact of the layoffs on the marine business, a Murray spokesman said they would not comment beyond the release.

Central Appalachian spot coal is $41 a short ton, about half what it was five years ago. A number of coal companies have filed for Chapter 11 bankruptcy protection in the past year including Arch Coal, St. LouisAlpha Natural Resources, Bristol, Va.; Peabody Energy, St. Louis; Walter Energy Holdings, Birmingham, Ala.; Patriot Coal Corp., Scott Depot, W. Va.; and Xinergy Corp., Knoxville, Tenn.

Barge operators – who haul one-fifth of the country’s coal – are well aware of coal’s problems. Plants are closing or converting to natural gas, prices and export demand are falling and coal producers are facing tougher environmental regulations.

Murray also is in contract talks with the United Mine Workers. The union recently rejected a proposed agreement with the company.

“This is a very hard time for everyone in the coal industry, especially those who actually mine the coal,” union president Cecil E. Roberts said in a statement issued before Murray’s announcement.

Dale DuPont has been a correspondent for WorkBoat since 1998. She has worked at daily and weekly newspapers in Texas, Maryland, and most recently as a business writer and editor at The Miami Herald, covering the cruise, marine and other industries. She and her husband once owned a weekly newspaper in Cooperstown, N.Y., across the alley from the Baseball Hall of Fame. A South Florida resident, she enjoys sailing on Biscayne Bay, except in hurricane season.