A stretch of the Whitefish River is closed while BNSF Railway workers investigate an oil sheen that appeared earlier this month on the shoreline near Roundhouse Landing.

City officials in Whitefish alerted the public to the sheen on April 11 while announcing the closure of the nearby bike and pedestrian path between Miles Avenue and Edgewood Place.

“The city of Whitefish received notice from BNSF of an oil sheen appearing on the Whitefish River,” the alert read. “BNSF is in the process of mobilizing equipment to do some investigation.”

City Clerk Michelle Howke said that although the river is inside city limits, they don’t have jurisdiction over it because the sheen occurred on BNSF property.

The sheen was first observed by a resident who reported it to a BNSF contractor on April 10, according to Amy McBeth, a spokesperson for the railway company. BNSF subsequently alerted state and federal authorities.

“There have been no reported spills or releases in the yard, and the issue is not related to any current railroad operations,” McBeth wrote in an email.

Officials with the state Department of Environmental Quality, which is monitoring the investigation as it is in the area of a state Superfund site, said Tuesday that the sheen likely came from groundwater affected by petroleum moving into the river. Recent snow melt may have contributed to its release.

Despite the sheen, there is no measurable amount of oil or petroleum in the river, officials said.

The agency is receiving regular updates from BNSF, according to Kevin Stone, a department spokesperson.

According to Whitefish City Councilor Giuseppe Caltabiano, municipal employees are working with the BNSF team as they seek updates on the sheen. Caltabiano said he was told the observed sheen was about the size of a tennis court, but was very thin, and is being managed as well as it can.

“From the data that I got from the staff, I am not concerned,” Caltabiano said.

City Councilor Ben Davis said his understanding is that the sheen is minimal and contained. He said that officials and experts at state and federal levels are saying the same thing: that the sheen is not as significant as it could be.

“Anytime there is oil coming out of that railyard, I think it’ll always be a cause for concern given the history of the property,” Davis said.

The sheen emerged in an area designated a state Superfund site owing to years of contamination from the nearby railyard. BNSF is working to design a permanent supplement to the existing system, but will continue groundwater pumping and other interim measures in the meantime, according to the Department of Environmental Quality.*

“DEQ may require additional investigation prior to approving a cleanup plan to address the source of contamination,” agency officials said in an initial statement last week.

The section of contaminated land, owned by BNSF Railway, has a history of soil and groundwater contamination. Public access to the area was established through a long term lease between the city and the railway company.

BNSF investigated a complaint of a petroleum sheen by the state environmental quality agency in the same area in 2019. The railroad company worked alongside the state officials and the EPA in the wake of the report.

According to Stone, the 2019 sheen was tied to remaining contamination in the upland areas adjacent to the river migrating to the river, at least partially through penetrations in the clay liner caused by tree roots.

In 2013, BNSF completed a major cleanup of the Whitefish River involving petroleum-contaminated soils under an administrative order from the EPA in the waterway, an undertaking that lasted five years.

Under the Oil Pollution Act, the EPA ordered BNSF to clean up the contamination from the river sediment and to restore the area. The railroad company removed more than 26,000 cubic yards of contaminated sediment and backfilled it on more than 1.5 miles of the river.

The investigation is ongoing and BNSF is continuing its analysis of the area.

Reporter Kate Heston can be reached at kheston@dailyinterlake.com or 758-4459.

*This paragraph has been updated to accurately describe who is completing the work.