New source of landfill methane spotted

Landfills’ work faces, the areas where fresh waste is dumped, are responsible for a huge share of methane emissions in US landfills , yet work face emissions have largely gone uncounted by traditional methods for monitoring greenhouse gases, according to a new study ( Environ. Sci. Technol. 2024, DOI: 10.1021/acs.est.4c07572 ). Most landfills do not measure these methane emissions because doing so is unsafe where heavy machinery is continually on the move. “You can’t really have someone walking around the site with a handheld instrument,” says Tia Scarpelli, a research scientist at the environmental monitoring organization Carbon Mapper and one of the study’s authors. “You don’t want to get hit by a bulldozer.” To overcome this problem, Scarpelli’s team used sensors attached to aircraft. After taking a bird’s-eye view of 217 landfills across 17 states in the US, the paper’s authors detected methane emissions at over 50% of the sites.