By BLAKE NICHOLSON, Associated Press

BISMARCK, N.D. (AP) — A 1,050-gallon oil pipeline spill in western North Dakota polluted a tributary of the Little Missouri River but was prevented from flowing into the larger waterway by its fast-moving current, a state Health Department official said Tuesday.

An estimated 756 gallons of oil and 294 gallons of saltwater, a drilling byproduct, leaked from a pipeline in Bowman County operated by Oklahoma City-based Continental Resources. The spill was discovered Saturday about 5 miles southwest of Marmarth, and more than three-fourths of the mess had been cleaned up as of Sunday.

Health Department environmental scientist Bill Suess was traveling to the site Tuesday and didn't have an update on cleanup. Continental Resources spokeswoman Kristin Thomas didn't immediately respond to a request for comment.

The company reported the spill Saturday and state officials went immediately to the site, which is in a remote area with little access, according to the Health Department, which announced the spill Monday afternoon. There was no danger to the public due to the delay, as no one lives in the area and anyone wishing to swim or fish in the creek would have been warned away by company and state officials at the scene, Suess said.

The cause of the leak was unknown, with excavation work still underway. There were no immediate indications of damage to wildlife or livestock, according to Suess.

The spill polluted a 14-mile stretch of Little Beaver Creek. The company believes fewer than 50 gallons made it into the water, with the Health Department estimating about double that, Suess said.

"At the time of the release there was a high-enough flow in the Little Missouri that it was actually pushing water back up into Little Beaver Creek, so that prevented any from getting into the Little Missouri," Suess said. The Little Missouri is a tributary of the Missouri River.

The oil has a thick consistency that causes it to clump together in the water.

"It forms these little balls and they float down the river," Suess said. "It's pretty easy to collect."

The spill was much smaller than a December leak on the Belle Fourche Pipeline in Billings County that spilled about 530,000 gallons of oil, one of the largest spills in state history. The spill dumped crude into a separate tributary of the Little Missouri River, but not the river itself.

No immediate decisions have been made on any possible fines in either case, Suess said.

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