Pollution outflows to Sound routinely allowed

(Editor's Note: This story has been changed since it was first published. About 400 million gallons of treated sewage is pumped into Puget Sound every day by the region's treatment plants. The number was overstated in the earlier version.)

Dozens of sewage-treatment plants and industrial facilities are discharging pollutants into Puget Sound at levels that could harm marine life or human health, but environmental regulators allow the practice because the waste is supposedly diluted.

That's the gist of a report issued Monday by People for Puget Sound, a Seattle-based environmental group, based on a review of the records of 103 sewage-treatment plants and 15 major industrial facilities dumping waste into Puget Sound or its tributaries.

Although the concentrations of the pollutants in the waste are relatively low, about 400 million gallons are pumped from treatment plants into the Sound every day -- and that goes on all year. It adds up annually to more than 28 metric tons of zinc, 8.7 metric tons of copper, 3.6 metric tons of lead and 2 metric tons of arsenic.

Federal and state environmental authorities allow violation of water-quality standards for a specified area around the spot where pipes disgorge waste. That area is called a "mixing zone," and the concept is common throughout the country, even though the Clean Water Act never explicitly allowed it.

"The bottom line is, we don't know what harm is being caused, and we know a lot of toxic chemicals are coming out in large amounts," said Heather Trim, the author of the study.

She said mixing zones amount to a huge loophole in the Clean Water Act because polluters in danger of violating the looser standard of mixing zones can get an even larger zone approved merely by moving the end of the discharge pipe to deeper water farther from shore.

"They do not serve a purpose when it comes to toxic chemicals, because they don't motivate people to go back and do the (pollution) control that's necessary," said Trim, the environmental group's program manager for urban bays and toxics.

The environmental group's report quantified only six pollutants that are most consistently checked: arsenic, cadmium, lead, copper, zinc and a widely used industrial chemical known as Bis(2-ethylhexyl)phthalate. An additional 50 or so pollutants are discharged by at least some facilities, but those six pollutants were the most consistently found across the 118 plants.

The environmental group called its effort "a first cut" at quantifying the overall amount of the six pollutants going into the Sound, using the pollution permits issued to each facility.

Some of the results are based on a little guesswork, but officials at the state Ecology Department and at the U.S. Environmental Protection Agency did not take issue with the way the study was done.

In fact, Ecology's own hired technical expert, a consulting firm named Tetra Tech, said in 2007 that the agency needed to improve its methods for figuring out whether marine life is being harmed by mixing zones.

And on Monday, Ecology spokeswoman Sandy Howard did not dispute the report's conclusions. But, "Mixing zones are part of the current regulatory framework that we're under," Howard said. "It's one of the most stringent in the nation, and it's been approved by the federal government."

She said, however, that Ecology officials are focused on doing something more effective than eliminating mixing zones by trying to stop pollution at its source, before it ever gets into sewage.

The mixing zones, she explained, are allowed only after a sewage-treatment plant or a business has taken "all known and reasonable" measures to reduce pollution.

Officials are reconsidering how to treat the mixing zones, Howard said, as the state and others gear up to reinvigorate flagging efforts to restore the health of Puget Sound.

David Ragsdale, who works on pollution issues for the EPA, agreed that the testing requirements for pollution discharges "may or may not be adequate" for determining the safety of the discharges.

He said state and federal regulators "strive to write permits that are protective of water quality," but still, "I'm advocating that we improve the treatment standards."

The biggest pollution loads come from the King County sewage-treatment plants at Discovery Park in Magnolia and in Renton. The Renton plant's waste is pumped all the way down the Duwamish River and dumped off Alki Point.

Randy Shuman of the county Department of Natural Resources said mixing zones are appropriate for pollutants that don't build up in the food chain, but not for those that do build up, which are dubbed "bioaccumulative."

"The idea of a mixing zone is, (water-quality standards) are allowed to be exceeded in a small area that is far from ecological and human contact," Shuman said. "If you think about it, it's almost a recognition that to have the concentration lower than that would be very expensive."

He said treating water to that level "could require a lot of expense for a fairly small payback in the cleanup of the Sound. I think our money would be better spent on other things."

Most discharges in question are unlikely to harm humans because their mixing zones are far from shore. In a few cases in Skagit and Whatcom counties, however, the study pinpointed places where waste is dumped into water upstream of another community's drinking water intakes.

Environmentalists challenged the application of mixing zones, among other aspects of water-quality regulation, in a 2006 lawsuit against the EPA in federal court in Seattle. The suit is pending. People for Puget Sound was involved in that process early on but dropped out before the suit was filed.

THE TOP FIVE POLLUTERS

Top total dischargers of the six pollutants studied: arsenic, cadmium, copper, lead, zinc and Bis(2-ethylhexyl)phthalate, based on permits issued by environmental regulators, in pounds per year:

King County Discovery Park sewage-treatment plant: 23,810

King County Renton sewage-treatment plant (discharges off Alki Point): 14,284

Kimberly Clark paper plant, Everett: 8,824

Tacoma sewage-treatment plant: 5,363

Lacey-Olympia sewage-treatment plant: 3,785

Source: People for Puget Sound