BILLINGS — The struggle to recover 30,000 gallons of oil from a pipeline spill into Montana’s Yellowstone River is expected to grind to a near-halt in coming days as warmer weather makes ice on the river increasingly dangerous, state regulators and a company spokesman said Wednesday.

Because of brittle ice, crews trying to recover oil trapped beneath the Yellowstone could be pulled off the river as early as Thursday, said Bonnie Lovelace with the Montana Department of Environmental Quality.

Monitoring of the river would continue, and any oil that washes up along the riverbank still could be cleaned up, said Bill Salvin, spokesman for pipeline owner Bridger Pipeline LLC of Wyoming. 

The monitoring area includes a 90 mile-stretch of the river between the spill site south of Glendive to just across the North Dakota border. 

Roughly 1,200 gallons of oil have been recovered from the river so far, Salvin said.

The 12-inch pipeline broke Jan. 17 after a section of the line became exposed beneath the river for undetermined reasons. 

It was the second oil spill into the Yellowstone since 2011, when an Exxon Mobil pipeline break during flooding fouled an 85-mile stretch of the river with 63,000 gallons of crude. 

In a Wednesday interview, Montana Department of Environmental Quality Director Tom Livers defended preparations made by regulators for another accident in the wake of the 2011 spill. But he said the latest spill shows periodic company surveys of pipeline river crossings remain inadequate.

The Poplar Pipeline that broke upstream of Glendive, temporarily fouling the city’s water supply, was last surveyed in 2011. It was determined at the time to be buried eight feet beneath the river.

Livers said his agency plans to consult with federal pipeline safety officials about inspecting other pipeline crossings to see if more are at risk. But he was unsure if that could happen before spring runoff causes rivers to rise, putting any other exposed lines at risk.

After the Exxon spill, a safety council established by then-Gov. Brian Schweitzer released a series of recommendations meant to guard against another spill.

Livers acknowledged at least two of those recommendations were not met: Maintaining an updated map of the state’s pipeline network through an agreement with federal officials who collect the information, and holding twice-yearly public meetings about pipeline safety with the directors of the state Departments of Transportation, Environmental Quality and Natural Resources and Conservation.

Still, Livers said the “most substantive” of the recommendations were enacted, including an expansion of the state’s spill response capabilities and training for state personnel.

“I would say it was a surprise (that the Poplar Pipeline broke) but we were not caught off guard,” Livers said. “We were way more ready for it as opposed to (the Exxon spill) when we were figuring it out as we went along.”