Study: More can be done to reduce landfill methane emissions

United States-based environmental advocacy group Industrious Labs says mandatory methane collection systems at large municipal sold waste (MSW) landfills represents one path toward lowering emissions in the landfill management sector.

In a 34-page report released by the group in late October, Industrious Labs writes, “Today, many landfills that emit methane are not required to install gas collection systems.”

Industrious Labs cites an analysis by the Washington-based Environmental Integrity Project from earlier this decade, with that study indicating of the 10 highest emitting landfills in the country in 2021, only eight are required to install and operate gas collection systems, while two don’t meet current federal thresholds.

The group also says capture systems can be put in place earlier to be more effective at preventing emissions of methane, a greenhouse gas (GHG).

In this case, Industrious Labs cites U.S. Environmental Protection Agency research that shows 50 percent of the carbon in food waste degrades into methane within its first three-and-a-half years under landfill cover.

However, EPA rules allow five years to pass before landfill operators are required to expand gas collection systems” to include newly filled areas.

“As a result, 61 percent of methane generated by landfilled food waste is released into the air, where it has an immediate planet-warming impact,” Industrious Labs says.

“Solutions to keep organic waste out of landfills. ... Diverting organic waste alone can only address new emissions, not the methane generated from previously landfilled waste.”

Landfill operators throughout the U.S., including Phoenix-based Republic Services Inc. and Houston-based WM, have been investing in landfill methane capture and energy conversion services for several years.

“Republic Services is investing in sustainability innovation to provide decarbonization solutions,” Republic Services Senior Vice President Tim Oudman said earlier this month when the company held a ribbon-cutting ceremony at the Keller Canyon Landfill in California as it ramped up of a landfill gas to renewable natural gas plant there.

Such efforts can be encouraged by additional EPA regulation and support, Industrious Labs says.

“By committing to update landfill emissions regulations in 2025, EPA has taken a significant step toward addressing the urgent climate and public health harms posed by landfilled waste," the group continues. "Now, the agency must draft rules that address gaps, improve oversight, and ensure accountability.

"As the third-largest source of industrial methane emissions in the U.S., landfills emission reductions are critical to any strategy to reduce methane emissions.”