The technology that is cleaning petroleum at the former Pasco Marine Terminal is no longer effective, according to a consultant's report.
That's what Port of Pasco commissioners learned during a recent update about cleanup activities on about a fourth of the 60-acre marine terminal area east of the cable bridge.
Cleanup of petroleum and chlorinated hydrocarbons is being performed by an in situ air sparging and soil vapor extraction system, said Teresita Bala, the state Department of Ecology's site manager for the cleanup.
The system blows air into the ground water and captures contaminants in air bubbles, she explained. That air floats into the soil, and then is sucked out by the soil vapor extraction system, which uses a vacuum to remove air from the soil. The contaminants are then treated.
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The state's review of the cleanup in 2009 showed that some of the polluted areas were not responding quickly to that system, Bala said. DOE suggested Crowley Maritime and the port consider additional cleanup methods.
Crowley Maritime, the parent company of the main petroleum company that used the terminal, leads cleanup efforts, and the port has authority to review and approve the work.
Now, DOE is waiting to hear back about solutions, she said.
Work is progressing but there needs to be an effort to speed up the remainder of the cleanup, Bala said.
So far, two of the nine contaminated areas have been cleaned, according to the report by consultant Golder Associates. And more than 58,000 pounds of total petroleum hydrocarbons have been removed.
About 70 percent of the site meets cleanup levels based on ground water tests, according to the report.
The consultant report did not suggest an alternate technology for cleanup.
The cleanup progress is now slow when the cost is taken into consideration, said Randy Hayden, the port's director of planning and engineering.
Crowley Maritime pays 63 percent of the cleanup costs, an Ecology grant pays about 28 percent and the port pays about 9 percent, with some of that covered by settlements received from other companies.
So far, $9.4 million has been spent on cleanup activities, Hayden said. That includes $4.1 million from Crowley Maritime and $2.9 million from Ecology. The port has paid $2.4 million, with all but $100,000 of that covered by settlements from other companies that were potentially liable for the contamination.
The port owns the property, and had leased it to a company that operated petroleum tanks in the 1950s, Hayden said.
The state first investigated contamination at the site in 1973, and a cleanup action plan was completed in 1997, according to the state Department of Ecology's website.
Construction of the treatment system on the site began in 2001 and finished in 2006 with three different phases, Bala said. The treatment apparatus can be rotated from one area to another.
The contamination was taken into consideration when the port and city of Pasco recently created the Boat Basin and Marine Terminal Subarea Plan for the area, Hayden said.
The plan recommended land use of commercial, mixed use and open space between the cable bridge and the railroad tracks. Residential uses require a higher clean up standard than commercial uses.
The earliest cleanup is expected to be complete is 2016, Hayden said.