Fuel leak likely hit aquifer
Diesel fuel and motor oil spilled from a broken pipe at a Hauser, Idaho, railroad refueling depot have seeped into the Spokane Valley-Rathdrum Prairie Aquifer, said Marc Kalbaugh, site remediation manager with the Idaho Department of Environmental Quality.
Despite the evidence of contamination, Kalbaugh said he believes the ground water remains safe for drinking. The aquifer supplies drinking water for Spokane and Kootenai counties.
“Based on the information I have, I don’t think there’s a risk,” he said.
Kalbaugh based his assessment on field observations, but he stressed that little is known about the true extent of the leak. “We don’t have any hard and fast data in our hands right now. … We don’t understand the vertical and lateral extent of the contamination.”
The leaking 8-inch-diameter PVC pipe was designed to transport wastewater and spilled fuel from the depot’s high-speed locomotive fueling platform. The break was discovered Dec. 10, but Burlington Northern and Santa Fe Railway Co. officials said they believe the pipe had been leaking since the facility opened Sept. 1.
BNSF spokesman Gus Melonas confirmed Monday the railroad detected a “petroleum aroma at the ground-water interface” at one of nine soil test drill sites. The discovery prompted the drilling of two additional groundwater testing wells, bringing the total number of water test wells to four. The new wells were drilled Monday above the suspected location of the fuel plume.
“There was no evidence of petroleum observed in field screening at either one of these two down-gradient wells,” Melonas added.
The new wells need to be flushed for 72 hours before accurate samples can be gathered, Kalbaugh said.
Details on the leak and subsequent contamination testing have been slow to trickle out of either BNSF or the DEQ, prompting criticism from local political leaders. Post Falls Mayor Clay Larkin said he plans to talk to the regional supervisor of the DEQ today to press for more information on the spill and a swifter release of data that’s been collected.
“The public needs to know what’s going on,” Larkin said.
Kootenai County Commissioner Gus Johnson sent a letter Thursday to the railroad asking for a detailed report of the situation, including when the leak was discovered and when it was reported.
“The Board of County Commissioners has been receiving numerous inquiries about what happened and what the Board is doing about the situation,” Johnson wrote.
Despite prodding, both the state and the railroad initially refused to share preliminary results Monday from soil and water sampling. Early in the evening, however, Kalbaugh provided the first confirmation that tests show fuel and oil reaching the aquifer 160 feet below the surface.
The determination was made using a field instrument, as well as a “sheen” test, during which soil is placed in a pan and covered with water, Kalbaugh said. Soil contaminated with hydrocarbons releases a telltale rainbow of color on the surface of the water.
An off-site laboratory is further analyzing the samples, Kalbaugh said, and will use the samples to calculate the spread of the plume. The state expects to release a more detailed report of the situation late next week.
Traces of petroleum were never detected in monitoring wells at the Hauser depot, Kalbaugh said. The wells were installed as part of the railroad’s operating agreement with state and local authorities.
“Those have been monitored every day,” Kalbaugh said.
Answering the question of how much fuel was spilled won’t be easy, according to state and railroad officials. The pipe was part of an unpressurized drainage system that collected about 2,300 gallons of wastewater daily from the depot’s refueling area and fuel tank storage site. The water includes rain, snowmelt and rinse water from the fuel platform.
Kalbaugh estimated that diesel, motor oil and coolant comprised “likely 1 to 2 percent of the solution.”
The $42 million Hauser depot was expected to pump more than 225,000 gallons of diesel daily into BNSF locomotives. The facility pumped fuel for 101 days before the wastewater pipe leak was detected.
The pipe was buried about 9 feet below the surface in one of the few areas not protected by a fluid containment system. Two layers of high-density plastic were buried below the rest of the refueling platform.
The railroad has already removed 200 cubic yards of contaminated soil down to a depth of 32 feet from the area surrounding the leak, Kalbaugh said. The soil is being stockpiled on-site, but has been covered to prevent additional leaching of fuel into the soil. The soil will eventually be hauled away for treatment and disposal.
No decisions have been made yet on how to clean up the rest of the contamination, Kalbaugh said. “Everything’s being weighed.”