MDU Resources Group, Inc.'s subsidiary WBI Energy Midstream, LLC, has agreed to sell its interest in the Pronghorn natural gas processing plant.

WBI Energy Midstream has a 50 percent non-operating share in the plant near Belfield, as well as the associated natural gas and oil-gathering pipelines, with Whiting Oil and Gas Corporation.

Tesoro Logistics Rockies, LLC, has agreed to purchase the plant and associated gathering lines — 137 miles of natural gas-gathering pipeline and 143 miles of oil-gathering pipeline — for $200 million. WBI’s share of the sale price would be approximately $100 million.

“This sale allows us to strengthen our balance sheet and provide cash to invest in other opportunities,” Martin Fritz, president and CEO of WBI Energy Midstream, said in a statement. “After recently exiting the refining business, this sale further reduces our exposure to commodity prices and reduces overall risk in our portfolio of assets."

The sale is expected to close in the first quarter of 2017, pending Federal Trade Commission approval.

WBI Energy Midstream acquired its interest in the Pronghorn facilities in May 2012 for $66 million. 

Reach Jessica Holdman at 701-250-8261 or