Alpha Natural Resources Inc. sold its West Virginia natural gas operation to Kinzer Drilling Co. LLC, the company said May 30.

The assets comprised substantially all of the New River Energy gas operation and include 120 producing natural gas wells in five counties. The terms of the transaction weren't disclosed.

Kinzer Drilling is an affiliate of Kinzer Family Group, which is a family owned and operated business based in Eastern Kentucky, according to the company's website.

In May 2016, Alpha also sold its core Marcellus and Utica shale acreage in central Greene County, Pa., in a bankruptcy auction to Vantage Energy LLC for $339.5 million. Vantage was later acquired by Rice Energy Inc. (NYSE: RICE) for $2.7 billion.

Alpha CEO David Stetson said the company will continue to pursue sales of other non-strategic assets.

Alpha also announced the divestment of its Green Valley mining assets in Nicholas and Greenbrier counties, W.V., to Quinwood Coal Co.

“With these significant divestitures, we will transfer 28 mining-related permits, reduce surety bonding by approximately $3.5 million, eliminate future reclamation spending at these sites, and further reduce our annual holding cost for inactive and idle properties by approximately $1.1 million,” Stetson said in a statement.