Since Minneapolis’ curbside organics recycling program rolled out in 2016, over half of the city’s households have ordered a small green bin to sit alongside their recycling and trash bins, where they can toss banana peels, bones, nail clippings, pizza boxes and more. Recycling coordinator Kellie Kish says 20-30 new households sign up for a bin each week, which is free for those with City collection service.
The curbside organics program alone collects more than 6,000 tons annually which gets hauled down to Specialized Environmental Technologies’ Rosemount facility—one of only two sites in the state that composts food waste on a large scale. Here, bulldozers start the process by blending together ground up yard waste and food waste. Like a monstrous cake, yard waste acts as the dry ingredients and soggy food waste is the wet ingredients. That mix gets pushed into a long pile that sits atop a 200 ft aeration tube. “Essentially a souped up leaf blower,” explains Jake Duame, who has monitored the food waste brought here from Minneapolis for years. “It’s a thick walled cardboard tube that we poke holes into to release oxygen throughout the pile.”
Oxygen riles up the microorganisms within and as the internal temperature jumps as they get busy breaking down everything from egg cartons and chicken bones. Composting permits mandate that the piles stay above 131 degrees for at least a week to destroy pathogens like salmonella, weed seeds and invasive insect eggs. Duame checks the mega thermometer poking out from an older pile on-site, which is cooking at 164. “In the winter when you break into these, you see steam just billowing out from the piles,” says Duame, who will come to work after a heavy snow to see a blanket of white across everything but the brown compost piles.