Organic waste and greenhouse gas
One thing I hadn't fully understood about municipal landfills how much food waste ends up there, and how the anaerobic conditions cause organic material to release methane. According to this explanation from the EPA, methane is 21 times more potent a greenhouse gas than carbon dioxide. And two researchers at Penn State recently found that 34% of the material going to state landfills is compostable organic material (press release).Like many apartment dwellers in Pittsburgh, I throw away all of my food waste. I'd guess that two-thirds of my garbage is produce scraps. Living on the 5th floor (without a garden) has prevented me from composting, so I'm contributing to the creation of unnecessary methane, as well as extra CO2 from the garbage trucks needed to haul the food waste. Pennsylvania has plenty of landfill space, so the state hasn't tackled this problem.
But what if the city provided garbage disposals in all homes? Would the extra cost for installation, maintenance, and wastewater treatment be offset by savings in transportation and storage, as well as have a longterm impact on the climate? (Curbside pickup of more recyclables and compostable material would be the ideal, but that sounds even more unlikely.)
This is waaay outside my area of expertise, so I'm slowly tracking down the original sources and stats and trying to figure out what info you'd need to do the calculation. More updates here as I have them. But I'd appreciate any ideas from environmentally savvy readers out there.
Comments
Here are some photos from an old student in my dept:
Worms!
Is it possible for you and your neighbors to have a more traditional compositing bin on the property?
A compost specialist from Oregon (a friend of my mom) also recommended this Japanese indoor compost bin, and this super-expensive automatic one. But I like the idea of worm-assisted composting, especially if the odor-free claims are true.
My concern is that most apartment dwellers won't bother to compost, but they see having a disposal as a luxury, a perk that's not only really easy to use, but that could improve the city's green image, too.
That said, I don't know of a particularly good way of doing this in a big-city highrise apartment building.
My "home" city (Dieppe, NB) does curbside compost pickup, by the way. It gets trucked to a composting site, so you don't save on transportation costs -- you just save on landfill costs, and on fertilizer for local farms. Residents can pick up a bag of compost yearly.
Last point: the wastewater system is full of stuff you definitely don't want to farm with -- storm runoff, feces, household chemicals. The soil you'd get out of such an operation would need to be trucked to a landfill site. Not clear this is a win.
Oh, wait, post-last: (a) the landfill sequesters any carbon from food scraps that remains after anaerobic rot; (b) the methane is increasingly being captured and sent to be burned for electricity; (c) burning methane generated from biomaterials like food waste is carbon-neutral.