University of Florida researchers in the Department of Environmental Engineering Sciences (EES) have developed a framework for designing custom soil covers at landfills to reduce harmful emissions.
There are more than 3,400 active landfills in the U.S. About half of them accept household wastes, while the other half accept debris from construction and demolition projects. The environmental conditions that naturally occur within landfills (e.g., low oxygen and the presence of carbon and moisture) combined with the presence of sulfur-containing wastes (e.g., gypsum drywall) can lead to emissions of hydrogen sulfide (H2S). H2S is a gas with a strong rotten egg odor that can be harmful to humans at low concentrations, and fatal at higher ones.
“Controlling emissions at these landfills poses a serious challenge, and conventional control technologies can be expensive,” said EES professor Timothy Townsend, who along with colleagues published this research in the January 2014 issue of Journal of Hazardous Materials. “Engineers and operators can use this new framework to find effective low-cost alternatives to improve working conditions onsite and protect the quality of life in the community.”
Townsend previously conducted research demonstrating the effect that different types of cover soils – such as dirt mixed with lime or crushed concrete – can have on H2S emissions at landfills. This new research builds on previous results, providing a design framework that can be used to create site-specific soil covers to help meet emissions goals. This site-specific flexibility is critical because every landfill has a unique combination of waste types, operating practices and climatic conditions.
The end result is a simple set of procedures and tests that can be applied anywhere and can reduce emissions in landfills and in their surrounding communities.
Contact: Timothy Townsend, Ph.D., P.E., ttown@ufl.edu