UI Dining Services have composted 72 tons of food waste from campus dining halls in three years, cycling it back into the university’s miniature ecosystem.

But only pre-consumer food waste — or food that was made but never served — is put into the compost, leaving what’s left on the half-full students’ trays with no place to go but a black trash bag.

Fred Kurt, the manager of Hillcrest Marketplace, said the magnitude of waste would grow tremendously if they added students’ leftovers to the mix.

“lt’s a different monster,” he said. “We would have to do things in a completely different way. Student waste would triple or even quadruple the load that we would take to the landfill, and there just isn’t enough room right now.”

But officials said they hope the student waste will be added to the compost load in the future.

Every week, the UI dining halls churn out 1.3 tons of waste.

Hillcrest kitchen employees gather any unserved food waste along with scraps from salad or produce and foods that can’t be served the next day. The leftovers are then transported by vans to the lowa City Landfill and Recycling Center, where the meals’ remains are combined with yard waste to form an environmentally friendly compost.

The efforts are part of the UI officials’ attempts to make the campus more sustainable. Hillcrest started composting extra food three years ago, and the Burge dining hall joined it last spring.

Both of the UI dining halls are working on more advanced, efficient methods to deal with the ever-increasing waste composted every week.

Iowa State University has a food-waste policy similar to the UI’s plan. ISU officials said they’re working to abolish trays in cafeterias, based on research that suggests trays may encourage students to take more food than they actually eat, said Nancy Levandowski, the director of lSU Dining.

Kurt said composting food has countless benefits. Recycling reduces the bloated heaps of trash bursting from overflowing landfills, as well as the greenhouse-gas emissions and carbon dioxide leaking into the atmosphere.

The compost created by Burge and Hillcrest is used to fertilize the entire UI campus, most notably the student garden where officials grow food for the dining halls.

Dave Jackson, an assistant to the UI associate vice president for Facilities Management, said he thinks the most exciting aspect of the university’s food recycling program is the student involvement.

“The fact that the compost goes back into the student garden on campus, and the food at the student garden feeds students, faculty, and food service staff, brings full circle the idea of locally grown food,” he said. “These were student-driven initiatives and show the commitment of our UI students toward becoming a more sustainable institution.”