(Bloomberg) -- Continental Resources Inc., the oil and gas explorer founded by billionaire Harold Hamm, is exploring a sale of a non-controlling stake in its water-infrastructure business that could value the unit at $1 billion or more, according to people familiar with the matter.

The Oklahoma City-based company is working with an adviser to solicit interest in the unit, which helps gather and dispose of water used in drilling in North Dakota’s Bakken shale and the Scoop and Stack fields in Oklahoma, said the people, who asked to not be identified because the matter isn’t public.

Continental fell 3.8% to $27.47 at 12:18 p.m. in New York trading, giving it a market value of $10.3 billion. The shares have fallen 58% in the past year.

Representatives for Continental didn’t immediately respond to requests for comment.

Infrastructure for handling the immense amount of water used in hydraulic fracturing has become increasingly valuable in recent years, thanks to the shale boom. Continental has already taken advantage of that dynamic, selling some of its water business in Oklahoma to Lagoon Water Solutions for $85 million in July.

Continental got a "decent price," Hamm, Continental’s chief executive officer, said in the company’s second-quarter earnings call in August.

"We estimate that our remaining water assets are valued at approximately $1 billion," Hamm said. "Our water infrastructure assets represent more shareholder value that is not currently being recognized by the market."

Its water business generates about $100 million in annual earnings before interest, taxes, depreciation, depletion, amortization and exploration expenses, he said.

Such free cash flow can support significant borrowings because it’s anchored by oil and gas exploration volumes, Continental has told suitors, the people said.

Continental has also told suitors that it’s a proven partner, the people said, with strategic relationships with companies including Franco-Nevada Corp., an investment company that owns natural resources royalties.

--With assistance from Rachel Adams-Heard.

To contact the reporters on this story: Gillian Tan in New York at gtan129@bloomberg.net;Kiel Porter in Chicago at kporter17@bloomberg.net

To contact the editors responsible for this story: Alan Goldstein at agoldstein5@bloomberg.net, ;Liana Baker at lbaker75@bloomberg.net, Matthew Monks, Pierre Paulden

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