BELLINGHAM - Eight years after the Port of Bellingham took over 137 acres of waterfront industrial land from Georgia-Pacific Corp., cleanup of mercury contamination in soil is ready to begin.
"It is a significant milestone," said Mike Stoner, the port's environmental manager.
The small-scale first phase of that cleanup will begin in March 2013 and be finished by May. It will focus on small mercury hot spots at the site of G-P's chlor-alkali plant and mercury recovery unit, said Brian Gouran, environmental site project manager for the port.
As Gouran explained it, G-P used mercury as part of an electronic process that converted salt (sodium chloride) into chlorine gas and sodium hydroxide. The sodium hydroxide was used to help break down wood pulp for paper, and the chlorine was used to bleach it.
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Mercury, a liquid metal, is valuable, and the company tried not to waste it, Gouran said. But during decades of operations, mercury did enter the soil via small leaks and spills.
In two small areas, both of which are not much larger than a couple of parking stalls, small globes of mercury can be seen in the top layers of soil. Because liquid mercury is both hazardous and difficult to control, Gouran said the contaminated soils can't just be dug out with a backhoe. The heavy liquid metal might roll right out of the scoop and back into the hole.
Instead, the cleanup crew from Strider Construction Co. of Bellingham will use suction equipment to extract the soil to a depth of 10 to 15 feet - about 500 tons. Depressurization wells will be drilled nearby to keep groundwater from seeping into the excavation.
The soil will be conveyed to the mercury cell building still on the site that will be modified for safe processing of the mercury-tainted soil. That soil will be mixed with sulfur to turn the elemental liquid mercury into a solid chemical compound. Then it will be mixed with cement and cast into blocks so that it can be safely trucked to an approved disposal site in Arlington, Ore., Gouran said.
The air inside the building will be filtered before it gets outside, and air quality monitors also will be in place around the excavation sites. Once the waste processing is complete, the mercury cell building will be demolished.
This small first phase of the cleanup will cost $1.8 million, with half of that money coming from the state's Model Toxics Control Act money that comes from a tax on petroleum and other potential pollutants.
In later stages of the cleanup process, on the mill site and in the adjoining sections of Bellingham Bay, soils and sediments with smaller concentrations of mercury will be covered with clean material to prevent exposure to people and other living things. Port Commissioner Mike McAuley acknowledges that while not everyone is happy with that approach, it meets the legal standards based on scientific research. Going beyond those standards would be expensive.
"You want to do a $10 cleanup, but you only have eight bucks," McAuley said. "I would say it's reasonable, with the caveat that it's not perfect. ... I think at the end of the day it will be as safe as we can make it for the money we have available. You bury it and try to sequester it and keep people from digging it."
Wendy Steffensen, lead scientist at RE Sources for Sustainable Communities, said she is glad to see mercury being removed from the waterfront site. But she has some misgivings.
"In general I think it's a step forward," Steffensen said. "It's great that we're removing the mercury. The danger is that nothing will happen to the rest of the site."
She noted that plans for the full cleanup, with a price tag likely to be above $100 million, are still being developed.
But the port already has a funding source in place for the full cleanup, in the form of a prepayment to an insurance company that will provide money needed to match grants from the state's toxics fund
Steffensen said she also wants to review details of the plans to keep workers and the general public safe from emissions during the mercury excavation.