Industrial past takes toll on Lake Washington

By Sandi Doughton
Seattle Times staff reporter

High levels of toxic chemicals or PCBs were found in the cutthroat trout, shown here, the pikeminnow and yellow perch.

E-mail this article Print this article Search archive Most read articles Most e-mailed articles

The news that Lake Washington's sparkling waters harbor fish laced with toxic chemicals may be shocking to many — but not to environmental regulators who know the area's industrial past.

Washington's state inventory of toxic hot spots includes about 50 sites with known or suspected PCB contamination in the expansive watershed around the lake, said Larry Altose, of the state Department of Ecology.

They range from sprawling complexes such as Boeing's Renton plant and a former Navy base to municipal landfills and an old filling station. The PCBs, which were once commonly used in industry and manufacturing, have seeped into soil and groundwater, and in at least one location, have tainted the lake sediments.

Of the 50 sites, only five have been completely cleaned up, according to state records.

It's not clear if PCBs, or polychlorinated biphenyls, from any of the contaminated areas are still making their way into the lake. And even if all the sites were cleaned up, it probably wouldn't solve the problem that led state health officials on Tuesday to warn anglers to cut back on consumption of three fish species from the lake, Altose said.

"These things are already in the environment," he said. "We're confronted with the legacy of many decades of PCB use."

Scientists don't know if the new fish findings hint at broader problems in the lake ecosystem, or whether other types of fish are dangerously contaminated as well. But the PCB discovery underscores the fact that despite its postcard appeal, Lake Washington was once home to timber mills, power plants and shipyards, and is still a sink for runoff from a major metropolitan area.

"These pollutants tend to be higher in urban areas, and Lake Washington is an urban lake," said Randy Shuman, of King County's Department of Natural Resources and Parks.

Improved condition

Decades ago, the lake was in much worse shape, choking on 20 million gallons a day of barely treated sewage from surrounding suburbs. A 1968 newspaper article called it "Lake Stinko."

"When I was 12 or 13, we'd go down there and drop a line with a worm 2 feet deep, and you couldn't see it anymore because the water was so dirty," said Jerry Beppu, who for 40 years has operated Linc's Fishing Tackle on Rainier Avenue South.

Launched by public referendum, the newly formed government entity dubbed "Metro" orchestrated a massive cleanup effort in the 1960s, rerouting sewage to a modern plant on Puget Sound. By the early 1970s, the water was visibly improved.

"Now, you go down there and it's so clear you can see the rocks," Beppu said. "For someone to say there's contamination there, I don't understand it."

But the types of chemicals showing up in fish today, including mercury and the pesticide DDT, are invisible and long-lived — and weren't a priority for cleanup in the past, Shuman said.

"Now that we're getting more sophisticated in our measuring techniques, we're seeing more problems."

PCBs in particular persist in the environment for decades. That indestructibility was what made the oily liquids so popular for use as insulators in electrical transformers, industrial coolants and mechanical lubricants. Banned in the late 1970s after the discovery that they can cause cancer and other serious health threats, PCBs were by that time so ubiquitous that they're found in polar bears in the pristine Arctic.

In lakes, PCBs attach to sediments. The concentrations in the water are very low and pose no danger to swimmers. But the chemicals enter the food chain through bacteria and small creatures that root around on the bottom. The chemicals can reach high concentrations in long-lived animals at the top of the food chain.

One top predator species in Lake Washington — the western pikeminnow or squawfish — averaged more than 1,000 parts per billion of PCBs, the highest level ever detected in state fish, the Health Department reported last week.

Cutthroat trout and yellow perch averaged 375 and 191 ppb, respectively. Levels under 100 ppb are generally considered safe.

The Health Department warned anglers not to eat pikeminnow and to limit consumption of cutthroat and perch.

(See the full recommendation at: www.doh.wa.gov/ehp/oehas/EHA_whats_new.htm.)

Offer of aid in testing

The U.S. Environmental Protection Agency has offered to help the state expand fish-tissue testing in Lake Washington, said toxicologist Lon Kissinger, of the agency's Seattle office. The tests will be conducted at EPA's Manchester Environmental Laboratory near Port Orchard in Kitsap County.

Some of that testing, which probably won't start until next year, will also target fish from Lake Union, said Dave McBride, of the Department of Health. "The lakes are so closely linked, and obviously, there's been a lot of industrial impact on Lake Union," he said.

The agencies also plan to test additional fish species, including rainbow trout, crappie, sunfish and carp. Sockeye salmon, which have a short life span and spend much of their time in the ocean, had very low amounts of PCBs in their tissues.

A recent King County survey found PCB contamination in more than a third of the sediment sites sampled in Lake Washington, with concentrations ranging from 6 to 343 parts per billion.

By comparison, PCB levels in the heavily polluted lower Duwamish waterway averaged 438 parts per billion, McBride said.

Similar sampling found almost no contamination in Lake Sammamish.

Sediments near plant

While the county survey didn't find any obvious hot spots in Lake Washington, previous analyses identified a concentration of contaminated sediments at the south end of the lake, near Boeing's Renton plant and the former site of the Shuffleton Steam Plant, an oil-fired electrical generating station built in 1928 and permanently closed in 1989.

The levels weren't high enough to bump the site to the top of the Ecology Department's list of cleanup priorities, said DOE sediment specialist Peter Adolphson.

It's possible, though costly, to cap or dredge tainted sediments, but that's probably not feasible if the PCBs are scattered throughout the lake, Shuman said.

"There's no factory making PCBs beside Lake Washington that we can turn off," he said. "It's not a very satisfactory answer, but I think the levels will slowly decrease with the passage of time."

Sandi Doughton: 206-464-2491 or sdoughton@seattletimes.com

Copyright © 2004 The Seattle Times Company

E-mail this article

Print this article

Search archive

More local news headlines...