Peabody Energy representative Beth Sutton told the Craig Daily Press that production would remain at about 8 million tons a year going forward.

She said the workers were being let go because one of the mine’s three continuous miners was being idled. That unit had been developing the mine’s next longwall panel, a project which is now complete.

Twentymile, located in Routt County, will have a total workforce of 525 after the staff cut.

“The Twentymile mine has run three continuous mining sections since 2008 to keep up with longwall development needs,” Sutton told the paper.

“With development work in the third section coming to a close, the mine will operate two continuous mining sections this year, in addition to the longwall. We have matched our staffing levels to our production needs.”

Peabody said the impacted workers were offered severance packages but did not disclose details.

Last month, fellow Colorado mine Colowyo Coal announced a 10% reduction in its staff, impacting some 30 workers at the Moffat County operation.

Mine officials cited long-term purchasing contract issues for the decision.

Colowyo sold 4.5-6.4Mtpa from 1994 to 2008, but projects selling only 2.5Mt in 2010. The company had sales of 2.7Mt in the first nine months of 2009.