A breach in a treatment pond being used for cleanup efforts on the Whitefish River caused water to flow into the river at the BNSF railyard earlier this month.

Heavy rains caused the pond to fill and overflow its bank. The water was near the end of the treatment phase and is considered safe, according to Dave Romero, on-scene coordinator with the U.S Environmental Protection Agency.

Cleanup crews use a dredge to suck the petroleum-contaminated sediment and water up from the river, then pipe it to ponds in the BNSF yard. The sediment is separated from the water, is treated and then returned to the river.

On June 5 the pond in the second stage of the water treatment system was being filled for the first time when it overflowed. A berm around the pond had settled since construction.

Romero said because the pond is toward the end of the treatment process, the escaped water is safe.

“It was already past where there would be a release of any of the material we are taking out,” Romero said. “We know that the majority of the contamination is with the sediments. I don’t anticipate any concern.”

Samples from the pond are being tested for contaminates, but the water has already been found to have no detectable levels of petroleum. During the breach, 300,000 gallons of water overflowed into the river.

Contractors have already cleaned up from the discharge and repaired the pond, which has been dug deeper. BNSF plans to make repairs to the city bike path that was damaged during the breach and stabilize the bank and restore vegetation that was disturbed as a result of the incident.

Despite the incident, Romero said cleanup efforts are going well this season.

“For all intents and purposes it’s going smooth,” he said.

Last year mechanical issues and debris in the river hampered progress. Using a new hydraulic dredge this year seems to have work on schedule.

“We’ve already done more that we did the entire season last year,” Romero said. “That is a big plus.”

Work began at the Second Street bridge a few weeks ago and last week crews had made it downstream beyond the bend in the river. Crews still have to return to the bridge area of the river to re-clean a few areas that weren’t sufficiently cleaned last year.

“So far it’s running pretty smoothly,” Romero said. “We’re making about 150 to 200 feet per day.”

Crews are removing sediment down to the clay layer. Once the contamination is removed, then the sites are tested. After they are confirmed as clean the sediment is filled back in.

This is the fourth phase of work to clean up petroleum products in the river sediment at several sites along the river. Sept. 20 is the anticipated completion date with a goal of reaching Spokane Avenue.

About 14,800 cubic yards of material are expected to be removed from the river this year.

The cleanup project was initiated after the EPA received a report in 2007 of an apparent sheen at several locations along the river. Citing the Oil Pollution Act, EPA ordered BNSF to clean up petroleum contamination from the Whitefish River and to restore it to as close to pre-removal conditions as possible.