State environmental regulators are proposing to allow Alcoa to monitor pollution leaching from an old landfill on the site of its former Vancouver aluminum smelter, rather than requiring an expensive cleanup.
The final cleanup action plan, to be released today for a 30-day public review, represents the last step to address Alcoa’s lingering industrial legacy along the Columbia River.
o What: A hearing on the state Department of Ecology's proposed cleanup action plan for the old Alcoa site at 5701 N.W. Lower River Road in Vancouver.
It follows last year’s $10 million cleanup of a shoreline tainted with high levels of polychlorinated biphenyls, or PCBs.
The state Department of Ecology isn’t proposing to force such an expensive remedy for the old unlined landfill 50 feet back from the Columbia’s shoreline. Instead, the Pittsburgh-based company will be required to monitor groundwater polluted with trichloroethylene, or TCE, until it ultimately dissipates into the river.
TCE is a type of industrial solvent that, like PCBs, is a suspected carcinogen.
The level of TCE in the groundwater below the landfill is above the state’s cleanup threshold, but officials contend that it’s impractical to force a cleanup that’s estimated to cost $22 million to $24 million.
“Water-treatment technologies using groundwater pump-and-treat systems and reactive barriers were examined and were not practical for this site,” according to the proposed cleanup action plan.
Groundwater in the area moves toward the Columbia River. The volatilizing chemical tends to evaporate once it moves from groundwater to surface water, where a less stringent cleanup standard applies. There are no wells within 1,000 feet of the landfill, so a Department of Ecology official said the agency sees no need to require a complicated groundwater treatment system.
“We’re going from a very low risk to the river to no risk to the river at very large expense,” said Carol Kraege, an Ecology manager overseeing the cleanup.
The landfill contains an estimated 175,000 cubic yards of industrial waste.
Since 1940, Alcoa has filled it with wire, cable, metal piping, alumina, scrap aluminum, carbon bake oven bricks, concrete, brick rubble, carbon, plant floor sweepings, drums, pallets, conveyor belts, paper, plastic and general construction debris. Since the smelter closed permanently a decade ago, the company has used it to consolidate waste from other landfills on the 208-acre site.
In 2003, Alcoa covered the landfill with a permanent cap.
The cap prevents direct human exposure to industrial waste, but state officials say it also prevents rainwater from seeping through the waste material. Over the past several years, Alcoa has detected declining levels of TCE in the groundwater. That may indicate the waste is no longer contributing new pollution, officials said.
Ecology has not contemplated ordering Alcoa to excavate and remove the landfill.
“Complete removal of surface waste would not make the site clean since the groundwater would still be contaminated,” the agency wrote in response to questions from The Columbian.
The tainted plume is in the groundwater below the 7.7-acre landfill site, meaning it would have to be accessed by a well drilled horizontally from the side, Kraege said.
“That just wasn’t going to pencil out,” she said.
The smelter site is now owned by the Port of Vancouver, which recently extended railroad lines across the property and plans to convert it for general industrial use and marine cargo handling. The landfill itself includes a deed restriction so that it cannot be used in a manner that would puncture the cap.
“It doesn’t impact our development plans,” said Patty Boyden, the port’s environmental services director.
Once the cleanup plan is adopted, it will mark the end of Alcoa’s seven-decade history in Vancouver.
Lured by inexpensive hydro power, Alcoa opened the Northwest’s first aluminum smelter along the Columbia River shore in Vancouver in 1940.
In the short term, the plant turned out the raw material for American warplanes that eventually overwhelmed the Axis powers in World War II. Over the long term, the smelter was the linchpin of Clark County manufacturing for more than half a century, employing as many as 2,000 people at a time.
The smelter closed for the final time during the West Coast energy crisis of 2000.
