In 1985, Ungurean co-founded Oxford predecessor Oxford Mining with his brother and current Oxford president-chief executive Charles Ungurean.

He leaves all his formal responsibilities with the company, including his post as equipment procurement and maintenance senior vice-president but has expectations to continue work on a part-time, at-will basis in a non-executive capacity.

Although officially terminated and resigned from his management duties, Ungurean will continue to receive a salary and benefits for his at-will commitments with the miner.

Ungurean has also served Oxford as vice president and secretary and is a certified surface mine foreman.

Oxford produced 8 million tons of coal in 2011 and counted 62Mt of proven surface coal reserves and 81Mt of proven underground coal reserves as of December 31, 2011.

The company recorded a $US16 million loss in the first quarter of 2012 due to impairment and restructuring charges related to its problematic Illinois Basin operations.