When food sits in landfills and starts decomposing, it releases methane, a potent greenhouse gas that causes global warming. Food waste is responsible for over 50% of methane emissions released from landfills, according to the EPA.
California and eight other states mandate composting to reduce the amount of food sent to landfills. But most of the laws haven’t done much, except in Massachusetts, where waste is down more than 13% — according to a new study published in Science. KCRW speaks to the researchers: Robert Evan Sanders from UC San Diego and Yannis Stamatopoulos from The University of Texas at Austin.
What constitutes food waste? Edible items that have been trashed, plus inedible organic materials like banana peels and eggshells. It is the most common type of trash found in landfills.
Sanders says composting laws should have reduced landfill waste by at least 10%. Some states, however, had more lofty goals. California said it would reduce statewide organic waste disposal by 50% by 2020. Within three years, organic waste disposal dropped by only 0.2%.
Businesses account for the majority of the 87 billion pounds of food wasted annually in the U.S.
So what did Massachusetts do differently? Stamatopoulos says the state employed simple rules that were actually enforced.
“Businesses know whether they're covered or not, and what the consequences are if they don't comply. Two: It should be economical for those businesses to comply with the law, meaning it's not incredibly expensive to employ a hauler to take the food waste to composting facilities. And third, there should be some kind of enforcement of the law. And in all these three dimensions, Massachusetts did far, far better than any other state. So yeah, it seems like Massachusetts did everything right.”
Massachusetts also mobilized inspectors who issued citations when garbage bins (in stores) they checked contained significant amounts of organic waste.
“If there's enough enforcement, and there's a chance that you get a fine … that would start to bring in haulers, right? They make their money based on route density, so if enough grocery stores want to start separating and doing this, and restaurants and so forth, then that'll bring in haulers, which will create a tipping point where compliance is fairly easy,” says Sanders. “But when it's hard to separate and haul your waste to an organics facility … the optimal move for many businesses might just be to not comply, especially if there's a low probability of getting caught.”
Meanwhile, California is stepping up its composting enforcement. Sanders points to SB 1383: If jurisdictions fail to enforce the organics diversion laws, they could get fined $10,000 a day.
“Just voting alone is not enough,” says Stamatopoulos. “You should follow up and make sure that businesses are complying, and that it's economical for them to do so. .. Increasing enforcement could go a long way. Maybe examining how to enhance the infrastructure strategically. … These laws can work, but you … have to take the measures needed to help the law succeed.”
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