The Kittanning, Pennsylvania-based company resumed production in February at an undisclosed number of mines in Pennsylvania, according to Jim Barker, the company’s executive vice president. The January furlough affected 429 miners, about half of the company’s approximately 850 employees.

The restart was aided by the company’s resumption of shipments to key electric utility customers that cut back on deliveries late last year after the winter of 2015-2016 got off to a warmer-than-normal start. While Barker did not identify the customers in question, at least some of Rosebud’s coal is sent to the 1,824-megawatt Homer City power plant in Indiana County, Pennsylvania. The big baseload plant is owned by GE Energy Financial Services. Some $750 million has been spent in recent years on environmental upgrades to the plant, in commercial operation since 1969.

Barker attributed the modest increase in coal demand in February to a two-week stretch of cold weather in the region. Overall, however, the winter has been relatively mild throughout the region, generally attributed to one of the largest El Ninos in decades.

Privately owned Rosebud, headed by Cliff Forrest, has continued to operate its three underground steam coal mines in Ohio: Vail, Tusky and Bergholz No. 7.

Altogether, Rosebud produces about 7 million tons of coal annually.

In late 2015, the Ohio Division of Mineral Resources Management issued a final permit for Rosebud’s new Ginger Bend underground steam coal mine in Guernsey and Belmont counties. The mine is expected to produce at least 1 million tons of coal annually, according to Brent Heavilin, permitting manager for the state agency.

The Ginger Bend permit covers 5,826 underground and 108.5 surface acres.

Later this year, the Ohio agency is expected to rule on Rosebud’s permit application for the new Dohrman underground mine in Harrison County.

Rosebud, founded in 1979, has not publicly disclosed development/in-service timetables for Ginger Bend and Dohrman.