One of Spokane’s oldest continuously operating industrial sites is slated for a $1.7 million cleanup aimed at keeping decades of fuel spills from reaching the aquifer.
BNSF Railway Co.’s rail yard on East Trent Avenue has been in use since the early 1900s.
Each day, hundreds of rail cars pass through the yard, which lies about a half-mile south of the Spokane River.
The site is used as a switching yard, where rail cars are reconfigured to get the cargo to its final destination, said BNSF spokesman Gus Melonas.
But the century of heavy use has left a legacy of soil contamination, including hydrocarbons from diesel, oil and gas spills, and leaking underground storage tanks, which were removed in 1990.
Arsenic, lead and other heavy metals also are present in the soil.
The combination of petroleum products and metals is typical of the pollutants found at long-standing industrial sites, said Sandra Treccani, site manager for the Washington State Department of Ecology.
The cleanup will help protect the underlying Spokane Valley-Rathdrum Prairie Aquifer, which provides drinking water to about 600,000 of the area’s residents, she said.
The Department of Ecology considered three cleanup scenarios.
The preferred alternative requires BNSF to remove the equivalent of 150 dump-truck-loads of contaminated soil from the site and to keep injecting oxygen into the groundwater to strip petroleum hydrocarbons from the soil.
The technology “sucks the contaminants out of air pockets in the soil,” Treccani said.
The hydrocarbons are collected and run through a filter, so the volatile compounds don’t end up in the air, she said.
The treatment began in 2009 to address a petroleum plume discovered in the groundwater.
Injecting the oxygen into the groundwater has been an effective treatment, and consultants estimate that the work will need to continue for another five years, Treccani said.
Public comments on the proposed cleanup plan for the site will be accepted through Oct. 31.
Treccani said the cleanup work would begin next spring or summer, after the Ecology Department enters into a legal agreement with BNSF, which is responsible for the cleanup costs.
BNSF has worked closely with the state both on past and current remediation programs for the rail yard and supports the preferred alternative, Melonas said.
“We look forward to continuing to make progress on this project,” he said.