Cedar Grove emissions test shows low-level toxins
State officials found some toxic substances at a Cedar Grove plant in King County, but stress the tests are incomplete.
The testing was done last June only to gather information about composting operations in general and not to investigate any operation in particular, said Chery Sullivan, an organics specialist with the state Department of Ecology, which conducted the tests.
"It's a little picture, we can't tell a whole lot from these measurements," she said.
The testing was done in two locations, at Cedar Grove Composting's Maple Valley plant in King County and a composting operation in Eastern Washington operated by another company. Like Cedar Grove's operation on Smith Island in Everett, the Maple Valley plant receives food scraps and yard waste, cures it and sells it as compost.
Both of Cedar Grove's locations have been the target of numerous complaints about bad smells the past few years and been fined for odor violations by the Puget Sound Clean Air Agency.
The testing was done to begin gathering data that can guide future regulation of composting operations, Sullivan said.
Neither Cedar Grove nor the other company are named in the report because the purpose was not to investigate any particular organization, she said.
"We wanted our own information on our own facilities," Sullivan said. "Most comes from other states and other studies."
The companies voluntarily allowed the testing to be done on their property, she said. The report, still in draft form, was first released in January.
Jerry Bartlett, environmental and sustainability officer for Cedar Grove, said the company does not comment on draft reports.
Mike Davis of Marysville, who has formed a group called Citizens for a Smell Free Snohomish County, doesn't believe the study goes far enough.
"Why didn't they test at the border of the property, why don't they test where it's affecting people?" he said.
The testing was done with a device called a flux chamber, which looks like a small flying saucer that sits on the ground with a large vertical tube protruding upward.
Emission levels were measured a foot above the surface at several locations around the Maple Valley plant, including the fresh, unprocessed pile of material; the pile of ground-up material; piles created early and late in the composting process; the "leachate lagoon," where water that runs off from the piles is collected; and the finished piles.
In addition to benzene and formaldehyde, the testing found ethylbenzene, acetaldehyde, ammonia and naphthalene, some of which are known or suspected carcinogens. The substances were not present in large enough amounts, however, to show that a health hazard exists, according to the report.
"The results provided in this report are statistically insufficient to conclude that an odor or toxic problem exists," the report states.
Smells were recorded as well. Amounts of materials detected, along with smell, varied between the different parts of the operation, according to the report. As might be expected, the fresh pile of material, the ground-up material and the leachate lagoon were among the smelliest locations.
Part of the reason for the study was to determine the relationship between odor and toxic substances, if any. On this point, the report was inconclusive, said state environmental engineer John Cleary, who wrote the draft report.
"Odors and toxics don't seem to flow together in the same cloud," he said.
Cedar Grove has applied to build an anaerobic digester to generate electricity from the methane gas found in compost at the Everett site. The public comment period on the application runs through April 6.
The city of Everett and the Puget Sound Clean Air Agency, which have approval power over the application, are not requiring Cedar Grove to do an environmental impact statement for the project. Cedar Grove has said the project would not involve processing more compost material, though documents filed with state and federal agencies as part of the application have shown the company expects to eventually process more than three times more organic waste than it does today.
"You need to do an EIS on what exists (at Cedar Grove) right now," Davis said.
Davis has been working with a nonprofit that produces the Toxipedia web site, which examines pollution issues, on researching composting. Nick Thorp, a researcher for Toxipedia who lives in Hawaii, has looked at the recent study.
He acknowledged it didn't raise any cause for alarm. Still, he'd like to see more information.
"Now that we know what these compounds are, let's take it a next step further, and do air emissions testing at the property line," he said.
Sullivan said this isn't likely to happen anytime soon. First, the state wants to collect basic information at all the compost operations around the state, of which there are about 40, she said. This could take years, depending on funding.
When that's done, she said, the work then could progress to more in-depth testing.
"We're primarily interested in creating rules that promote recycling of organic material in a manner that protects human health and the environment," Sullivan said.
Bill Sheets: 425-339-3439; firstname.lastname@example.org.
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