Runoff called top pollutant in Puget Sound
Findings prove what many suspected, and may change priorities in cleanup
Runoff from streets, roofs and even forests is the largest source of most of the worst pollutants plaguing Puget Sound, according to a study released Friday. Air pollution is the prime culprit for a few of the toxic chemicals. Oil spills and sewage treatment plants contribute smaller fractions of the waste.
Some of the findings were surprising -- and highlight the need to complete a more thorough analysis, possibly resulting in a refocusing of cleanup priorities.
"We're trying to sort of move away from random acts of kindness to prioritize actions based on the analysis and substance of what we find to be out there," said David Dicks, director of the Puget Sound Partnership, the government agency responsible for the health of the Sound.
The report is the first attempt to chase down and quantify all the sources of pollution that sicken orcas and make fish and shellfish unsafe for human consumption. It cost $135,000, paid for by the Environmental Protection Agency.
Millions of dollars have been spent trying to clean up historical contamination in Puget Sound and to stem ongoing sources. Many hope the investments will increase as the state and Gov. Chris Gregoire try to restore the Sound by 2020.
The report is the first part of a three-phase effort to tally the flow of toxics to the Sound. It comes with the warning that the numbers are preliminary and incomplete.
Findings include:
- Pollutants including arsenic, cadmium, copper, lead, zinc, mercury, the banned pesticide DDT and phthalates -- a chemical used in plastics -- came mostly from runoff from urban and non-urban areas. The greatest concentrations came from developed areas.
- Air pollution is a leading source for toxic flame retardants and polycyclic aromatic hydrocarbons, or PAHs, created when fuel is burned.
- Combined sewage overflows that dump untreated or partially treated sewage into the Sound during heavy rainstorms contribute little to the overall pollution, though they cause local toxic hotspots.
The report was vindicating for Rich Berkowitz, director of Pacific Coast Operations Transportation Institute, a non-profit representing the maritime shipping industry.
It found that oil spills accounted for only 4 percent of the petroleum pollution in the Sound; runoff from land accounted for nearly all the rest. The runoff -- according to back-of-the-envelope calculations by federal scientists -- could carry the equivalent of about half an Exxon Valdez spill a year in oil and grease.
"We are winning the battle on preventing oil spills from commercial vessels," Berkowitz said. "We've been losing the battle for far too long on runoff."
Continue reading this article from the Seattle P-I:
Runoff called top pollutant in the Sound
