Washington state has repeatedly let cities and companies discharge toxic pollution into Puget Sound at levels that are probably harmful to protected salmon, a coalition of environmental groups said Wednesday.

And the federal Environmental Protection Agency (EPA) is violating the Endangered Species Act (ESA) by letting the state's permitting system potentially contribute to the decline of salmon and other protected creatures, the groups claimed.

Five environmental groups filed a formal notice Wednesday that they plan to sue the EPA for inadequate oversight of water pollution. The move marks the first major effort since Puget Sound chinook were protected in 1999 to force the government to better control legal discharges and toxic stormwater runoff.

The EPA is responsible for water quality but has delegated that authority to Washington state since the 1970s.

State officials said they hadn't had time to review the complaints but maintain they use a "rigorous process" to ensure pollution discharges aren't dangerous.

"We feel like we're using the best science available," said state Department of Ecology spokesman Glenn Kuper.

The environmental groups, including Puget Soundkeeper Alliance and People for Puget Sound, commissioned a scientific report and cited numerous examples they said highlight failings in the state's system for controlling water pollution.

They claim Ecology has underestimated the number of polluted rivers and streams around Puget Sound.

They also contend the state has overestimated how effectively sewage and toxic discharges from 170 major industries and 86 wastewater-treatment plants are diluted once dumped into the Sound.

The state lets paper mills, oil refineries and other industries dump everything from mercury, lead and zinc to dozens of toxic organic compounds into the Sound, relying on computer models to ensure they are diluted in "mixing zones" before spreading to the rest of the Sound.

In addition, when rains run over parking lots, roads and construction sites, that washes heavy metals, bacteria, viruses, oil and pesticides into the Sound that, at the right concentrations, can harm the immune systems, spawning and development of fish and other species.

"All the copper, the toxic chemicals and the heavy metals they permit? How can it not be harmful?" asked Richard Smith, the lead attorney for the groups. "Can I prove that? I don't know. But I don't have to."

EPA has an obligation under the Endangered Species Act to consult with salmon managers, such as the National Marine Fisheries Service, any time the federal government takes an action that could hurt salmon.

Smith argued that even though the state is effectively in charge, EPA, as the oversight agency, still must prove to salmon managers that the permit system is safe. But EPA has not.

Mike Gearheard, who runs EPA's water-quality program in the Northwest and Alaska, said his agency rarely inserts itself into the state's management of pollution.

"We engage on a small handful of issues when they're important," he said, citing his agency's recent rejection of Washington's new water-quality standards for major rivers as an example.

He also said it's not clear that EPA is required to do more.

Craig Welch: 206-464-2093 or cwelch@seattletimes.com

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