Joy Youwakim is a senior at the University of Texas at Austin, where she studies economics. But often you can find her not on campus, but at a closed landfill southeast of the city by the airport, checking on a crop of vegetables she’s grown on top of the heap of trash.

In her work, Youwakim aims to create an economic case for sustainable agricultural practices: She spent her sophomore year growing sorghum in her faculty advisor’s backyard to prove that it’s both more economically and environmentally viable than corn, one of the country’s most popular and heavily subsidized crops. But that was just the beginning: That same year, Youwakim spent the summer working at the Texas Commission on Environmental Quality, where she met someone who was in charge of landfill regulation. He showed her an image of a local landfill, and Youwakim “was just blown away,” she says. “I thought it would look like a pile of trash, but it just looked like a dirt hill,” she adds. “So I said: ‘Why don’t we grow food on top of it?'”

In Austin, as in many cities across the U.S., the communities surrounding landfills often struggle economically. Del Valle, the community in which the Austin landfill is located, has been classified as a food desert. Many locals purchase their food at the gas station. Youwakim saw an opportunity to reanimate the landfill to meet some of that need.

She worked with the agency for over a year to secure the paperwork and permits that would allow her to pilot a farming project on the 330-acre landfill in southeast Austin. The landfill, which is full of trash and noxious chemicals, is covered with a liner, a heavy sheet of clay or fiberglass that locks in the noxious fumes from the garbage beneath. On top of the liner sits a layer of dirt and grass, to further seal in smells and to make the landfill look nicer. Youwakim had to ensure that the soil and grass on top of the pile was deep enough to support roots without breaching the liner and allowing the landfilled material to leach out. And then there’s the matter of stigma: How could she convince the public that it’s perfectly okay to eat something grown on top of a pile of trash?

Youwakim finally secured approval to plant last summer, and put the first crops, including cantaloupe, radishes, cucumbers, and green onions down in September 2017, hauling five-gallon jugs of water out to the landfill to fuel the plants. She harvested the produce a few months ago, and ran them through rigorous testing with Food Safety Net Services to ensure they were safe to eat (they were).

What started as a radical idea–Youwakim is the only person she knows of who’s trying to repurpose landfills in this way–has now landed her an opportunity. She’s among the five finalists for the inaugural General Mills Feeding Better Futures Scholars Program, which recognizes young people between the ages of 13 and 21 doing innovative work in sustainable agriculture and food distribution. The competition called for projects that address one of five issues: food deserts and access, food waste, water quality and conservation, pollinator health, and healthy soil and preservation.

The other finalists include Jack Griffin, who created FoodFinder as an interactive tool to help families map out and access exactly where to go in their communities to access free food assistance, and Braeden Mannering, who launched Brae’s Brown Bags, through which he and a network of volunteers in his native Delaware distribute brown bags filled with healthy food, clean water, and a kind note to homeless populations. Katie Stagliano, who’s now 19, started Katie’s Krops a decade ago to help young people start vegetable gardens, and there are now 80 across the country. Kate Indreland is tackling nutrient depletion in the soil of her native Big Timber, Montana, by rebalancing the nutrient contents in the ground, and has seen a 30% increase in nutrient density in the plants that grow from it.