Limiting Landfill Greenhouse Gas Emissions

Landfills are never going to be anyone’s favorite landscape feature. But there may be a way to move them down the “not in my backyard” list.

Nebraska researchers are studying how to remediate gas emissions from landfills with an innovative ground-covering system.

Jongwan Eun, associate professor of civil and environmental engineering, and Yunwoo Nam, associate professor of community and regional planning, began their work four years ago with a grant from the Nebraska Environmental Trust. They’re using a cover made from an extruded geomembrane with an ethylene vinyl-alcohol layer sandwiched between two inner, low-density polyethylene layers. The team is comparing this system in field tests to traditional covering systems made of low-density polyethylene and no covering.

This is the first time this approach has been tested.

Preliminary research results are promising: The new system, tested at a 3-acre landfill in Butler County, Nebraska, reduced gas emissions by 30 to 40% over conventional covers. Landfill gas emissions are the third largest source of greenhouse gases in the United States. They include hazardous, noxious gases that often worry landfill neighbors.

Researchers also are gathering and analyzing data about the new system’s potential impact on any given community using gas dispersion modeling. Knowing how far the gas travels with this new covering system is important for landfill planning.

The team also analyzed the new technology’s cost effectiveness.

“Although initially more expensive to install than the traditional approach, based on our simulation for the sixth and seventh year, there is a turning point where you will see a return on investment,” Nam said.

With less gas emissions, higher gas collection and greater return on investment, the method may soon be adopted by communities looking to upgrade their systems.

“I wanted to provide information that others can use for a good alternative to control and manage the greenhouse gases from landfills, which will be a huge benefit for the environment,” Eun said.