Landfills are places in perpetual motion, with piles of trash rising within days and workers racing to stop even more from coming in. Amidst the turmoil, invisible gases are often released unnoticed, warming the planet and negatively impacting our health. methane.
On Thursday, Carbon Mapper's climate data researchers studying science This shows that U.S. landfills are emitting levels of methane that are at least 40% higher than levels previously reported to the Environmental Protection Agency. At more than half of the hundreds of dump sites surveyed, the largest assessment of emissions of its kind to date found that the majority of pollution escaped through leaks, creating concentrated plumes. . The researchers found that these super-emission points can persist for months or even years and account for nearly 90 percent of all methane measured from landfills. Addressing these hotspots could be a major step towards reducing emission rates, but they often evade detection due to blind spots in current monitoring protocols.
„It's very hard to get everything right, with no leaks,“ said Daniel Cusworth, an atmospheric chemist and project scientist at Carbon Mapper, a nonprofit organization that provides data to inform greenhouse gas reduction efforts. It's a difficult issue.“ Cusworth occasionally conducts aerial surveys of the landfill, but is relieved when he finds nothing. “You can also see huge billowing plumes up to 3 kilometers long.”
methane is a powerful greenhouse gas produced by, among other things. rotten garbageAnd it often seeps through the soil and the plastic coverings used to contain it. Although federal regulations require large facilities to use gas recovery systems, landfills remain important locations. 3rd largest source of information Of these, the United States accounts for more than 14 percent of the national total.Because methane 84 times more powerful According to scientists, more carbon dioxide than in the first 20 years of existence in the atmosphere. reduce the amount Floating there is the quickest way. curb global warming. Doing so also benefits the local community. The number of landfills in the United States is disproportionate. near Marginalized areas exposed to gas affect health or there is a risk of explosion.
leakage exceeding The Clean Air Act limit of 500 ppm is common, as shown by the hotspots identified by Carbon Mapper. These areas typically occur after unforeseen events, such as cracks in the landfill cover, failure of valves in extensive gas collection systems, or other maintenance or construction issues. “They make up a large portion of the total landfill emissions,” Cusworth said. The study found that average emissions from the most studied locations were at least 1.4 times, and in some cases as much as 2.7 times, greater than the amounts reported to the EPA's Greenhouse Gas Reporting Program. Did.
![Aerial view of a Georgia landfill. Plumes of infrared methane, colored red, green, and blue, can be seen emerging from the top.](https://grist.org/wp-content/uploads/2024/03/cabonMapperGeorgia2plumes.jpg?quality=75&strip=all)
![Aerial view of a Georgia landfill. Plumes of infrared methane, colored red, green, and blue, can be seen emerging from the top.](https://grist.org/wp-content/uploads/2024/03/cabonMapperGeorgia2plumes.jpg?quality=75&strip=all)
carbon mapper
Federal guidelines require these facilities to track emissions and provide that data to the EPA, but current reporting and monitoring methods are not fully satisfactory, the study says. Most operators use EPA guidelines to report estimates based on the amount of trash they accept, rather than from measured data. Regulators also require facilities to conduct walking surveys four times a year, but experts like Cusworth say these efforts aren't frequent or accurate enough. Hotspots can easily go unnoticed because many areas are too dangerous to walk on, and monitoring sensors only respond to high concentrations on the ground and cannot capture dispersed plumes. „You can't manage what you can't measure,“ Cusworth said, adding that this is a common cliché in the air monitoring business.
In the study, Carbon Mapper researchers flew a plane over the landfill and took infrared images to reveal the plume. Similar remote sensing techniques include drones and satellites. recent technological advances This suppresses contaminants and allows facilities to quickly detect and respond to leaks. Other innovations in methane capture systems, such as self-calibrating caps on the valves and sensors that can detect leaks, further reduce the risk of failure.
“Especially in the waste sector, we have known for years which technologies to deploy. They are feasible, readily available, and in fact many of them are very cost-effective.” said Kate Siegel, Waste Division Manager for the Clean Air Task Force's Methane Pollution Team. “Regulations need to be in place.” This August, he said, the EPA will update its landfill management policy as part of his mandated eight-year review cycle.
Tom Frankiewicz, a methane scientist in RMI's waste division who collaborated with Carbon Mapper on the study, said the gas's short lifespan and extreme strength compared to longer-lasting carbon make it less viable for large sites like landfills. He said there is an urgent need to address large-scale sources of methane. Dioxide. The world won't realize the climate benefits of reducing CO2 emissions until a century later, he said. Curbing methane would shorten that period to 10 years. “We have to tackle both and rely on methane. it buys us time” And in the race to mitigate climate change, every moment counts.