Week of Jun. 11, 2007

County ‘swaps’ litter and debris for clean soil

A trommel extracts solid waste from reusable soil.

The Street Waste Alternative Program (SWAP) is a recycling and reclamation program for debris collected by the division. It has been in full operation since 2003, and in that time has turned 97 percent of the material it removes from county roads into usable material.

“We collect somewhere in the neighborhood of about 15,000 cubic yards a year,” said Doug Navetski, a senior ecologist with the Roads Division. “We want to do something with it in a responsible manner, so we run it through our SWAP program.”

The Division’s maintenance unit collects the debris through street sweeping and cleaning out storm drains. In 2006, the sweepers collected 4,128 tons of debris and another 5,762 tons was sucked out of the drains.

In order to turn the waste into soil, all litter and contaminants must be removed. For this task, the county uses big machinery along with some microscopic allies.

Soil comes off the conveyor belt to later be decontaminated.

Next, the soil is moved into covered bays where it's stockpiled and allowed to sit for several months. The dirt can contain small amounts of oil or other material. So to tackle that problem, the job is handed over to a smaller set of workers – bacteria and microorganisms that eat the contaminants leaving behind clean soil.

Before being used, the soil is tested to make sure it is safe enough for the environment. Once it’s ready, the division uses the reclaimed soil for fill dirt.

Before the SWAP program was launched, the county spent between $550,000 and $730,000 a year to dispose of waste solids from its roads. SWAP has cut that number by about half. And, even through it has a 97 percent efficiency rate, the county hopes to reduce that amount by the year 2030.

“Since 2003, the SWAP program has processed 30,000 cubic yards of materials that used to be sent to landfills,” said Debbie Arima, Roads Maintenance Manager. “This program saves the county money, it provides us with high-quality materials to use in other projects, and delivers multiple environmental benefits.”

Roads wins honors for White Center project The American Public Works Association (AWPA) Washington State Chapter has presented the King County Road Services Division an APWA Project of the Year Award for the 16th Avenue Southwest Pedestrian Improvements project in White Center. The award category was for “Historical Restoration/Preservation, less than $2 million.” The 16th Avenue Southwest Pedestrian Improvement Project was constructed within a four-block segment of the White Center Central Business District in unincorporated King County. The project boundaries were from Southwest 100th Street to Southwest Roxbury Street. Substandard sidewalks had lined both sides of 16th Avenue Southwest. Two other King County projects that received recognition in the APWA Project of the Year Award in the Historical Restoration/Preservation category were the Des Moines Memorial Drive Corridor and the Meadowbrook Bridge projects.

April is a big month for the Adopt-a-Road program An 'Adopt-a-Road' crew. The Road Services Division Adopt-a-Road Program celebrated Earth Day 2007 throughout the month of April. During the month, there were 47 clean-up events and more than 400 participating volunteers. Those volunteers contributed in excess of 1,000 hours and picked up 970 bags of trash from roadways in unincorporated King County.

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