Sound's future still murky
Development, growth, runoff threaten gains
By TOM PAULSON
P-I REPORTER
Scientists at the Pacific Northwest National Laboratory, after digging up and studying some well-preserved muck tracking Puget Sound's water quality changes going back to the 19th century, report both good and bad news for the ongoing effort to clean up the region's ecologically wounded waterway.
The good news is that repeat sediment analyses performed by the researchers over the past quarter-century show that when major pollution regulations were passed decades ago, there were marked declines in contaminants such as arsenic, lead and copper from "point sources," such as the old Asarco Smelter in the Tacoma area.
"It demonstrates the positive impact these environmental regulations had on the overall water quality of Puget Sound," said Jill Brandenberger, a marine chemist at the national lab's marine sciences branch in Sequim who, with national lab colleague Eric Crecelius, conducted the study.
The bad news, Brandenberger said, is that the sediments indicate that these dramatic gains started to slow down in the late 1980s -- and, in some cases, appear to have even started to worsen -- the result of "nonpoint" pollution from the region's population growth, development and consequent increases in contaminated stormwater runoff.
"If we continue on with what we're doing now, it is likely Puget Sound will never recover," Brandenberger said.
Never is a lot farther off than 2020.
That's the target set by Gov. Chris Gregoire and a fairly new state agency called the Puget Sound Partnership for finally restoring the inland marine body to a healthier, near-natural ecological state. An official "action agenda" was released earlier this month, asking for an additional $199 million on top of the plan to spend $400 million over two years.
On the 197-page agenda for the Puget Sound cleanup are some 150 recommendations, including beefed-up enforcement of shoreline regulations, improved building requirements that reduce stormwater runoff, more protection of fish runs and natural shellfish beds, mitigation of wetland damage from development and other measures.
A draft of the agenda drew ire from some experts who felt it failed to suggest strong enough actions to reduce runoff.
"It's been a little bit of a confused situation," said David Dicks, executive director of the partnership. Dicks acknowledged that the draft plan neglected to emphasize the need to control runoff, but said most of the early critics have since agreed that the final version sufficiently addresses the problem.
"This study is consistent with our own findings and shows we've got to get after this now," Dicks said.
Regulating effluent from a smelter is a lot easier than controlling pollution that comes from homes, gardens, automobiles and innumerable other sources that the region's regular rainfall eventually carries into the Sound.
On three occasions over 23 years, national lab scientists collected 10-foot-long sediment cores from the seafloor in various locations deep beneath the surface of the Sound. These cores, collected in 1982, 1991 and 2005, contain within them the chemical history of the marine water going back more than 100 years. Every centimeter of sediment, the scientists said, is like a "rap sheet of toxins" going back in time.
The first hazardous metals showed up in the sediments about 1890, the study found, when metal smelting began near Tacoma. Lead and arsenic (byproducts of the smelter) concentrations began rising, slowed during the Great Depression when work slowed and picked up again in amounts during World War II. With the onset of clean water regulations and with the closure of the smelter, Brandenberger and Crecelius found, marine arsenic levels have now returned to pre-industrial levels.
"This shows Puget Sound has the ability to recover," Brandenberger said. Lead levels have also declined, she said, but not as much likely because of lead still being dumped into the Sound by other sources of contaminated runoff.
But another class of chemicals associated with gasoline combustion known as PAHs (polycyclic aromatic hydrocarbons), Brandenberger said, is increasingly showing up in the sedimentary record. These byproducts of automobile use and other kinds of fuel combustion are entering the sound through runoff, she said.
The scientists say their findings strongly suggest that "new approaches to regulating nonpoint sources are necessary" if the Puget Sound cleanup is to have any hope of success.
P-I reporter Tom Paulson can be reached at 206-448-8318 or tompaulson@seattlepi.com.
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