Part one of an occasional series

Daily life near a landfill often comes with a stench: rotten eggs, sickly sweet chemicals, or even smoke that drifts into homes, schools, and nearby parks. For those living close by, who are disproportionately low-income and communities of color, offensive odors are just one concern. Landfills also contribute to local ozone pollution and release hazardous air pollutants, including known carcinogens benzene and vinyl chloride. People living near landfills report chronic headaches, nausea, and asthma attacks.

Meanwhile, these landfills are exacerbating a global problem. As buried food scraps and organic waste break down beneath the landfill surface, they generate methane, a potent greenhouse gas with 80 times the heat-trapping power of carbon dioxide over the near term. But because of its short atmospheric life, cutting methane today is the most effective way to slow warming in our lifetimes. When it comes to landfill methane, there are clear solutions that unlock major local benefits.

While reducing food waste and recycling organics are critical to prevent future methane generation, we must also strengthen landfill controls to cut methane quickly from buried waste and protect nearby communities. After years of concern, states are stepping up with smart policies to address landfill pollution. This spring, California launched a first-in-the-nation satellite program to track large methane leaks, and Colorado just released what could become the country’s most effective landfill methane standard.

These actions mark a new wave of ambition — but they were shaped by decades of community complaints, calls for cleaner air, and a growing awareness of landfills’ contribution to climate change. Recent innovations in methane monitoring and controls make it easier than ever to track and manage pollution at these sites. Actions taken by California and Colorado aren’t one offs — they’re part of a growing trend of rapid learning and adoption at the state level across the country.

Colorado Steps Up

Colorado’s proposed nation-leading landfill rule will address a major source of methane within the state to advance its climate pollution reduction goals. In 2020, Colorado landfills emitted 4.5 million metric tons of carbon dioxide equivalent, the same as putting one million gasoline-powered cars on the road for a year, according to state estimates using a 20-year global warming potential. And the true total is likely higher, as remote sensing surveys have found large methane plumes at landfills that aren’t captured in official inventories. These plumes raised concerns not only about the warming impacts, but also about nearby residents’ exposure to hazardous air pollutants and smog.

The proposed rule, presented at a request for rulemaking hearing on April 17, incorporates proven best practices and the latest technologies to better control landfill methane pollution. If enacted, more Colorado landfills would be required to manage their emissions by installing a gas collection and control system (GCCS). The rule would also phase out open flares (systems that burn methane gas in the open air), replacing them with enclosed systems to more effectively control pollution near fenceline communities. The rule is projected to be a major economic win for Coloradans, delivering six times the return in avoided costs for every dollar invested. It’s also a job creator, expected to generate 402 direct jobs and 1,382 indirect jobs by 2050 according to the Colorado Department of Public Health and Environment (CDPHE).

In a national first, Colorado’s standard would incorporate the latest advancements in methane monitoring — leveraging data from satellites and aircraft to ensure the largest leaks are quickly addressed while allowing operators to use drones and other approved technologies to conduct their routine monitoring surveys. The rule would also require some landfills to collect gas from active disposal areas — which are a major source of methane emissions that can be mitigated with horizontal or bottom-up collectors (perforated pipes or trenches laid within landfill waste to collect methane early) — and to install biocovers and biofilters, low-tech systems made of mature compost that can naturally break down methane without combustion when added to the landfill cover.

This shift matters to businesses, too. At a public meeting ahead of the draft rule’s release, Arapahoe Basin Ski Area, a member of America Is All In, made the business case for bold action on landfill methane.

Local economies built around outdoor recreation depend on long winters, healthy air, and a predictable climate. Business leaders, community members, scientists, and regulators all contributed to shaping Colorado’s recent proposal, grounding the rule in both science and lived experience. The result is a standard designed to cut harmful emissions and protect the people and places that make Colorado home.

Following the Path of Other States and Inspiring Improvements

Colorado is following in the footsteps of five other states — California, Oregon, Maryland, Michigan, and Washington — that have all set stronger standards than federal regulations to control landfill methane pollution. California set the pace on landfill methane back in 2010 with its Landfill Methane Regulation, which led more landfills to install a GCCS and monitor more comprehensively for leaks. In the years since, other states have built from California’s framework, adopting similar requirements for gas capture and control.

What makes Colorado’s draft rule different is that it’s the first to modernize the model — integrating the latest technology and practices. As the state moves toward the rulemaking hearing in August 2025, it can build from its nation-leading proposal by considering additional measures to boost transparency and protect frontline communities — such as integrating fenceline monitoring and requiring use of best available technologies. Meanwhile, all eyes are back on California as it considers updates to its own approach.

California doesn’t have to look far for inspiration. For example, in Orange County near Los Angeles, OC Waste & Recycling (OCWR) has gone beyond the state’s current requirements, launching a Smart Landfill Program that uses drones and real-time wellhead controls to monitor and manage methane more effectively. As regulators revisit the state’s decade-old rules, OCWR offers a glimpse of what stronger standards can achieve: cleaner air, healthier communities, and new economic opportunity.

More States Poised to Take Action

Federal rules helped define the basics, but states have sped past these standards to meet today’s climate, health, and equity challenges — and 2025 is poised to be a big year for landfill methane reduction.

As momentum builds, the opportunity for bold state leadership has never been clearer. The landfills will remain, but the daily disruptions and health risks they pose don’t have to. With proven models to draw from and homegrown technologies already on the market, states can set a new standard: one that prioritizes clean air, public health, and community, while pulling the emergency brakes on planet-warming pollution.

By modernizing systems and following best practices, landfill operators can also be a part of the solution, delivering real, measurable improvements to the people living nearby. The first dominoes have fallen, and this year, states are lining up to keep the chain reaction going.