At the Class of 1992 Talks at our 25th reunion in June, I welled up a bit along with my classmate Annie Kerr as she told of her son’s proclamation: “I want to be a garbage man when I grow up!” I heard pride tainted with dismay in her voice as she recounted her five-year-old’s awareness of waste in our society and his dreams for turning trash into treasure.

Recalling my own childhood in Seymour, Indiana, I thought, “Didn’t we all want to be garbage men at some point?” Then it hit me, “Aren’t we all garbage men and garbage women?” Aren’t we all persistently, consistently, and incessantly metabolizing organic and inorganic matter?

Life itself is defined by metabolism. Fail to metabolize, and you die. The deep ecological question of our hypersuccessful global species now becomes: how do we bring every molecule, every atom, full circle indefinitely as we shuttle matter back and forth between Earth’s biosphere and humanity’s technosphere?

After the reunion, I had plenty of time to ponder this on the train from Boston to Missoula, Montana, the self-proclaimed “Last Best Place,” where I’ve lived since 2010. It is here that I have relied on my Surly Big Dummy—a utility bicycle with a 500‑pound payload—to gather plastics, glass, metals, and paper and herd it all back to the manufacturing sector.

I decided to go zero-waste one summer morning when the titans of trash were servicing my neighbors’ bins. I strolled out onto Columbine Road with my single plastic bag weighing a pound or two—my “garbage” for the month—and flicked it into the garbage truck. A reprimand followed: I was not a paying customer. Immediately I realized that the landfill and all its fossil-­fuel-powered, hydraulic waste-­compacting trucks were not public, but private. Since I was not being taxed as a landfiller, I wasn’t entitled to be one. Under no obligation to make material or financial contributions to Mount Methane, I decided that with some creative recycling, I wouldn’t.

I set up a three-stream system. A chute from the house to the garage for glass, ceramics, plastics, and metals serves as the “build” stream. A second chute collects organics, such as tissues and food waste, for compost: my “bury” stream. Newspapers, paper cups, milk cartons, and other incendiaries go through the “burn” chute to heat our home. We pyrolyze medical waste.

For seven years, I served as director of the world’s first online renewable-energy technology program, at the University of Montana. In that role, I spoke at numerous conferences, such as the 2015 Harvesting Clean Energy Conference in Billings, where I took a deep dive into sustainability. I also toured hyperclean cities in Japan, met with researchers from the Korean Institute of Energy, and witnessed a coal purchase agreement between the state of Montana, the Crow tribe, the U.S. Department of Energy, and China. These experiences have made me keenly aware of the wide range of forms and definitions of “waste.”

Along the way, it’s become abundantly clear to me that we cannot afford to keep extracting and using fossil fuels 10 million times faster than they were created—particularly when their use generates waste in the form of carbon dioxide, methane, and oceans of plastic. (It does not take an MIT degree to understand this concept; when I talk to high schoolers about it, they quickly catch on.) So I’ve been working with University of Montana Regents Professor Steve Running, who served on the Nobel Prize–winning Intergovernmental Panel on Climate Change, to develop carbon-neutral policies and practices intended to bend down the Keeling Curve, the graph showing the concentration of carbon dioxide in the atmosphere since the 1950s. We’re also exploring the work of John R. Schramski, who sees Earth as a giant chemical battery that stores energy from photosynthesis as biomass and fossil fuels. We recently cofounded Integration Energy, a company that aims to help people clean and replant forests, kick the oil habit, recycle e-waste, go solar with their homes, and launch urban farms.

As our population approaches 10 billion, it’s more critical than ever that we live sustainably—and clean up after ourselves.

Bradley Layton ’92, cofounder of Integration Energy, formerly served on the faculty at the University of Montana’s Missoula College. His book Zero Waste in the Last Best Place is due out this year.