What Happens to a Landfill in a Hurricane?

In the coming days and weeks, as Floridians and others in storm-ravaged communities clean up from Hurricane Milton, trucks will carry all manner of storm-related detritus — chunks of buildings, fences, furniture, even cars — to the same place all their other waste goes: the local landfill. But what about the landfill itself? Does this gigantic trash pile take to the air and scatter Dorito bags and car parts alike around the surrounding region?

No, thankfully. As Richard Meyers, the director of land management services at the Solid Waste Authority of Palm Beach County, assured me, all landfill waste is covered with soil on “at least a weekly basis,” and certainly right before a hurricane, preventing the waste from being kicked up. “Aerodynamically, [the storm is] rolling over that covered waste. It’s not able to blow six inches of cover soil from the top of the waste.”

But just because a landfill won’t turn into a mass of airborne dirt and half-decomposed projectiles doesn’t mean there’s nothing to worry about. Because landfills — especially large ones — often contain more advanced infrastructure such as gas collection systems, which prevent methane from being vented into the atmosphere, and drainage systems, which collect contaminated liquid that’s pooled at the bottom of the waste pile and send it off for treatment. Meyers told me that getting these systems back online after a storm if they’ve been damaged is “the most critical part, from our standpoint.”

A flood-inundated gas collection system can mean more methane escaping into the air, and storm-damaged drainage pipes can lead to waste liquids leaking into the ground and potentially polluting water sources. The latter was a major concern in Puerto Rico after Hurricane Maria destroyed a landfill’s waste liquid collection system in the Municipality of Juncos in 2017.

As for methane, calculating exactly how much could be released as a result of a dysfunctional landfill gas collection system requires accounting for myriad factors such as the composition of the waste and the climate that it’s in, but the back of the envelope calculations don’t look promising. The Southeast County Landfill near Tampa , for instance, emitted about 100,000 metric tons of CO2 equivalent in 2022, according to the Environmental Protection Agency (although a Harvard engineering study from earlier this year suggests that this may be a significant underestimate ). The EPA estimates that gas collection systems are about 75% effective, which means that the landfill generates a total of about 400,000 metric tons of CO2-worth of methane. If Southeast County Landfill’s gas collection system were to go down completely for even a day, that would mean extra methane emissions of roughly 822 metric tons of CO2 equivalent. That difference amounts to the daily emissions of more than 65,000 cars.

That’s a lot of math. But the takeaway is: Big landfills in the pathway of a destructive storm could end up spewing a lot of methane into the atmosphere. And keep in mind that these numbers are just for one hypothetical landfill with a gas collection system that goes down for one day. The emissions numbers, you can imagine, start to look much worse if you consider the possibility that floodwaters could impede access to infrastructure for even longer.

So stay strong out there, landfills of Florida. You may not be the star of this show, but you’ve got our attention.

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