Longer Lasting Landfills Researched

Gainsville, FL— Emerging technologies could bring the answer to current waste management challenges. The Florida Department of Environmental Protection is sponsoring an outdoor experiment by the University of Florida that could significantly extend the lifespan of the nation's landfills and provide added protection to the environment.

The University of Florida has spent three years transforming a 13-acre garbage mound at North Florida's New River Regional Landfill into a huge "bioreactor." Next month, researchers will begin pumping leachate, the liquid that develops as rain percolates through the waste, into the garbage, kicking off a decay process that is designed to dramatically accelerate its decomposition.

"Today's standard practice isolates garbage in landfills from the ground by heavy-duty plastic liners," said John Schert, director of the Florida Center for Solid and Hazardous Waste Management at UF, which is managing the project. "By cutting the garbage off from air and a consistent source of water, the waste often remains preserved for decades, even centuries."

Infusing the garbage with water and air will spur proliferation of the natural bacteria that breaks down garbage, forcing it to decompose in the first few years when the liner is in the best condition. By breaking down garbage quickly, the bioreactor technology could significantly reduce the volume of waste in landfills, create space for more waste and reduce the threat of groundwater contamination.

"Nearly 70 percent of garbage is composed of paper, food scraps, cardboard and other material that decomposes," said Bill Hinkley, chief of DEP's Bureau of Solid and Hazardous Waste. "Using current landfill practices, bulky garbage fills space that could otherwise be used for more waste. The bioreactor could cut the bulk in half."

Landfills in Florida and elsewhere are already experimenting with bioreactor technology. The goal of this research is not only to find out how well the technology works, but also to create engineering guidelines that provide landfill designers with a roadmap for building effective bioreactor landfills worldwide.

"The reality is we continue to landfill the majority of our solid waste," said Tim Townsend, a UF associate professor of environmental engineering and co-leader of the project with Debra Reinhart, a professor of environmental engineering at the University of Central Florida. "If we are going to continue, we need to figure out better ways to design and operate our landfills."