A North Dakota well operated by privately held Petro-Hunt released 25,000 gallons, or about 600 barrels, of oil January 2 after a blowout.
The leak happened about one mile north of Keene, North Dakota in McKenzie County and was not contained on site, North Dakota’s Department of Health said.
Petro-Hunt said Friday the leak is under control and cleanup efforts have started.
No injuries were reported.
The cause of the leak is still being investigated.
The health department is currently responding to the incident and evaluating whether any of the released oil contaminated a nearby tributary of the Missouri River.
Petro-Hunt general counsel Fred Hosey told Reuters the Dallas-based company has “met all necessary regulatory requirements.”