CATALDO - An international energy company has installed containment booms in the Coeur d'Alene River and brought in a horde of work crews this week to search for a potential leak in a fuel pipeline crossing the water body.

ConocoPhillips is analyzing the stretch of Yellowstone Pipeline between Enaville and Cataldo, in response to a slow drop in pressure that occurred in that section of the 10-inch line on Saturday, said company spokesman Jeff Callender.

"We do want to reassure the public based on what we know now, we don't think there's a risk," Callender said, adding that there is no confirmation of a leak so far in the pipeline that carries unleaded gasoline. "But we have people monitoring the river 24 hours a day."

An official with the Idaho Department of Environmental Quality has ballparked 80 workers are on site right now, with a command center set up by the energy company at Silver Mountain Resort.

Callender said ConocoPhillips doesn't have an exact tally of workers yet, though.

The line was already shut down from last Thursday as part of normal operations, he added.

And since Saturday, ConocoPhillips has shut down valves along various legs of the pipe. It has also conducted aerial surveillance to scan for a leak, he said, with nothing found.

"We sent out personnel to start walking the pipeline right away, looking for signs of a break or damage," Callender said. "We had people out in the field for three or four days, continuing to walk the line."

Nothing yet, he said.

A containment boom has been placed at Cataldo below the boat launch, he added, and along River Road at Kingston to intercept a leak if it does occur.

Monitors are keeping an eye on the crossings 24 hours a day, too. At night, spotlights are brought out to beam down on the waves, Callender said.

"We can look for any evidence of a sheen or anything," he said.

The company has kept up daily correspondence with several agencies on the situation, he added, including the Idaho Department of Environmental Quality, the Environmental Protection Agency, the Department of Homeland Security and Shoshone County.

"We're trying to err on the side of caution and be very proactive," he said. "We're doing everything possible to determine what caused the pressure drop in the line, to identify that and correct it."

A drop in pressure can be caused by events besides a leak, he added, including vandalism of the pipeline.

The DEQ is monitoring the company's work, said Marc Kalbaugh, site remediation manager with DEQ.

The agency will be prepared to address environmental impacts if a leak is discovered, Kalbaugh said.

ConocoPhillip's next step is a physical inspection of the pipe, Kalbaugh said, with an acoustic listening device.

"They will eventually get that data back, and hopefully by Friday be able to have provided analysis of where within that section a leak is occurring," he said.

The energy company and agencies are aware of two areas where the pipeline is exposed in the river, Kalbaugh said, which have been temporarily addressed.

The exposures, probably caused by recent flooding, aren't likely to be the cause of a leak, he added.

"If there was a leak coming from an exposed pipe, we'd immediately see it in the river," he said.

The pipeline, which carries fuel from Missoula, Mont. to Spokane, crosses the river three times in the area of concern, Kalbaugh said.

John Specht, Shoshone County Emergency Manager, said he isn't worried about the situation yet.

"They were going to keep us informed and notify us if they found a leak," Specht said. "They've given us no news yet, and that's good news."

More action might eventually be necessary to analyze the line, Callender said, like conducting a hydropressure test or digging up the pipeline.

"We're still in the early stages of trying to determine exactly what caused the pressure drop and what to do to correct that," he said.