Skip to content Skip to footer

Landfills Belch Climate-Warming Methane. Even the EPA Doesn’t Know How Much.

Landfills are a major source of greenhouse gas, but emissions are rarely measured at the source.

Landfills are a major source of greenhouse gas, but emissions are rarely measured at the source.

It’s easy to forget about garbage. We put it out on the curb and it goes away, thanks to some of the hardest-working people around. But garbage continues impacting us — and the planet — long after it leaves our dumpsters. When all of our trash combines in a landfill, it becomes a serious source of climate-warming pollution.

Municipal solid waste landfills are the nation’s largest source of methane emitted by human sources after fossil fuels and agriculture, according to the Environmental Protection Agency. We send our garbage to as many as 2,000 such dumps nationwide.

Over a 20-year period, methane is up to 84 times more powerful than carbon dioxide in terms of trapping heat in the atmosphere.

At the recent COP26 climate summit, the United States and European Union led 100 countries in signing a pledge to slash methane emissions by 30 percent over the next decade. Trapping methane from landfills could help the U.S. keep its word, environmentalists say, but there’s a big problem: We don’t actually know how much methane and other pollutants are being belched by landfills into the atmosphere in the first place.

The EPA reports that municipal landfills were responsible for 15 percent of U.S. methane emissions in the 2019, which is roughly equivalent to the greenhouse gas emissions from 21.6 million cars on the road for a year. However, air pollution from most landfills is not measured at the source, and these figures are just estimates based on a method of modeling emissions that the EPA has not updated in two decades, according to Environmental Integrity Project (EIP) attorney Ryan Maher.

“That bad stuff is getting out, but I think we need to figure out how much is getting out as the first step to managing it,” Maher said in an interview.

Within a year of trash entering a landfill, anaerobic bacteria begin breaking down food waste and other organic garbage, producing methane as a result. Landfills also produce other pollutants, including the greenhouse gas nitrous oxide and volatile organic compounds that can be harmful to human health.

Maher said technologies such as drones and even satellite imaging can measure pollution from landfills directly, but tracking emissions costs money. Federal law requires larger emitters to install gas collection systems, and some landfills even trap methane to generate electricity. However, more accurate data on emissions could force more landfills to invest in pollution controls, which the industry is reluctant to do.

EPA’s current model for estimating landfill emissions is sorely outdated, Maher said, and is probably underestimating the amount of methane and other pollutants entering the air. For the industry, that translates to fewer state and federal regulations.

“It’s the EPA’s methods that decide whether gas control is necessary under those regulations,” Maher said, referring to pollution controls that suck gas from trash heaps through a network of pipes. “We think updating the methods will result in higher emissions estimates, which will result in more pollution controls under the EPA’s federal regulations.”

In 2008, the EPA reviewed its methods for estimating three landfill gases that the agency is required to track by federal law: volatile organic compounds, nitrous oxide and carbon monoxide. The model is based on methane emissions, which is also a good way to gauge climate impact, but the agency concluded that the levels of most pollutants were underestimated by 25 percent, according to a complaint filed by EIP and other environmental groups on Thursday.

The EPA proposed an update to the emissions model in 2009, but the proposal was never finalized or implemented, the groups said. The EPA is required by the Clean Air Act to review and consider updating the model every three years, but that review was not completed during the Trump administration. So, the groups announced their intention to file a lawsuit in order to compel the agency into action. A spokeswoman for the EPA said the agency does not comment on pending litigation.

“The EPA model is basically showing state regulators and the public which facilities are of most concern, and just where landfills fall generally as emitters of various compounds, and how they compare to other industries,” Maher said.

Last year an EIP analysis found emissions from 19 landfills across Maryland were four times higher than the official state estimate, and Maher believes a reworking of the EPA’s methods would yield similar results nationwide. Scientific studies on landfills have also found a gap between EPA estimates and actual emissions, and more accurate modeling would help policymakers make regulatory decisions and develop climate policy, he added.

The EPA, as well as a handful of state and local governments that keep greenhouse gas inventories, uses the data to track contributions to climate change. Measuring the amount of methane could encourage regulators and lawmakers to push for pollution controls that would help the country meet its emissions targets.

Local communities would also have better data for holding operators accountable for pollution from landfills, the majority of which are located near lower-income neighborhoods and communities of color.

We’re not backing down in the face of Trump’s threats.

As Donald Trump is inaugurated a second time, independent media organizations are faced with urgent mandates: Tell the truth more loudly than ever before. Do that work even as our standard modes of distribution (such as social media platforms) are being manipulated and curtailed by forces of fascist repression and ruthless capitalism. Do that work even as journalism and journalists face targeted attacks, including from the government itself. And do that work in community, never forgetting that we’re not shouting into a faceless void – we’re reaching out to real people amid a life-threatening political climate.

Our task is formidable, and it requires us to ground ourselves in our principles, remind ourselves of our utility, dig in and commit.

As a dizzying number of corporate news organizations – either through need or greed – rush to implement new ways to further monetize their content, and others acquiesce to Trump’s wishes, now is a time for movement media-makers to double down on community-first models.

At Truthout, we are reaffirming our commitments on this front: We won’t run ads or have a paywall because we believe that everyone should have access to information, and that access should exist without barriers and free of distractions from craven corporate interests. We recognize the implications for democracy when information-seekers click a link only to find the article trapped behind a paywall or buried on a page with dozens of invasive ads. The laws of capitalism dictate an unending increase in monetization, and much of the media simply follows those laws. Truthout and many of our peers are dedicating ourselves to following other paths – a commitment which feels vital in a moment when corporations are evermore overtly embedded in government.

Over 80 percent of Truthout‘s funding comes from small individual donations from our community of readers, and the remaining 20 percent comes from a handful of social justice-oriented foundations. Over a third of our total budget is supported by recurring monthly donors, many of whom give because they want to help us keep Truthout barrier-free for everyone.

You can help by giving today. Whether you can make a small monthly donation or a larger gift, Truthout only works with your support.