Cogswell, N.D. ? The temporary shutdown of the Keystone oil pipeline after a leak in southeast North Dakota will not affect deliveries to customers, the pipeline’s operator said.

Oil should be flowing again in a few days, Terry Cunha, a spokesman for TransCanada Corp., told the Argus Leader newspaper Monday. Officials first need to finish inspecting valves along the route, which runs from Saskatchewan and Manitoba in Canada through the Dakotas, Nebraska, Kansas, Missouri, Illinois and Oklahoma.

“We spoke to our shippers … and we will be able to make all the May deliveries once we restart,” Cunha said. “There’s no market impact on customers.”

A bad valve at a pumping station in North Dakota’s Sargent County caused the spill on Saturday, the company said. The state Health Department on Tuesday told The Associated Press that an estimated 350-400 barrels of oil spilled, down from an earlier estimate of 500 barrels. A barrel holds 42 gallons of oil. Most of the spilled oil was contained by a berm around the pumping station but some oil mist had to be cleaned from standing water in a nearby field.

The oil shot about 60 feet into the air when the valve failed, according to landowner Bob Banderet, who lives about half a mile from the station.

“It was higher than the cottonwood trees,” he told the Argus Leader.

Kris Roberts, an environmental geologist with the North Dakota Health Department’s water quality program, said groundwater contamination does not appear to be an issue.

The pipeline was shut down nine minutes after the leak, which was reported by Banderet. Cunha said the company already was shutting down the line when Banderet called because the system had detected a loss in pressure in the pipeline.

The rapid shutdown and assembly of a response team “clearly demonstrates that our pipeline safety system is working,” Cunha said.

The company’s risk analysis on file with the South Dakota Public Utilities Commission states that a leak of 50 barrels or more on the Keystone system would be expected once every seven years. The pipeline began moving oil last June. Cunha said the estimate does not apply to pump stations, which were not included in the risk analysis. Saturday’s spill was the 10th release of oil on the Keystone line, all of them at pump stations, he said.

Sargent County Commissioner Bill Anderson praised the company’s response to the spill. However, he said, “I have to confess: I did not anticipate that we would have a problem this soon.”