City seeks change in landfill law

COLUMBIA, Mo. -- Fifteen years after the state banned yard waste from municipal landfills, the city of Columbia is seeking an exception for its future power-generating bioreactor.

The $2.5 million bioreactor, expected to begin operating next year at the city landfill, will be the first in Missouri. The bioreactor will use water to speed the breakdown of organic waste in the landfill, in turn producing methane gas that will be turned into electricity.

Bills pending in the legislature would let the city dump tons of leaves, grass clippings and other yard waste into the landfill. Proponents of the plan say the yard waste could produce more methane gas, which in turn would produce more electricity.

The Missouri Department of Natural Resources supports Columbia's alternative energy project, but department spokesman Matt Easley said DNR would rather see the city compost the yard waste than put it in the landfill.

He said the waste might not be as productive as city leaders hope.

"We would rather see it composted," Easley said. "We think it could be more beneficial that way. The yard waste could decompose too quickly, and all the methane might not be captured."

Methane is a major greenhouse gas.

Sen. Kevin Engler, R-Farmington, who filed a bill in January that would allow yard waste to be used in bioreactors, said the criticism is misguided.

"That's basically what this is, a big compost," he said of the bioreactor. "It's a great idea that's got some potential."

Rep. Ed Robb, R-Columbia, is sponsoring a similar bill in the House.

The state banned yard waste from landfills in 1992. Legislators at the time argued the measure would conserve landfill space and promote other, "more beneficial" uses for organic material.

Dan Dasho, director of the Water and Light Department, said the bioreactor would supply about 5 percent of the city's electricity.

"We need to have the flexibility to do these sorts of things," he said.

Richard Wieman, the city's solid waste utility manager, said the yard waste could generate an extra 45 cubic feet of methane per minute. Methane from the landfill now is generated at about 800 cubic feet per minute, he said.

City Public Works Department crews now handle about 10,000 tons of yard waste annually, and it is trucked to a 15-acre compost site next to the landfill. If yard waste is approved for the bioreactor, it could save the city nearly $800,000 annually, according to reports from the city.