A lunch tray and an apple core placed in one pile, a plastic salad container placed in another: wearing full-body Tyvek suits, members of the Climate and Food Justice Club sorted cafeteria waste into three sections—trash, recycling and compost—in front of the STEM wing on Wednesday, Nov. 1.

The 133.4 pounds of waste was collected from first and second lunch the same day and poured onto a large blue tarp to be publicly examined, sorted and analyzed. This information allowed the club to determine how much improvement there was compared to their previous two audits.

The results from the audit showed less trash being used, over-composting and not enough recycling. Last year, 33.3 percent of total waste was sent to landfill, and this year, that number reduced to only 27 percent. On the other hand, 70.5 percent of waste this year was composted when only 54 percent of the waste was compostable. Additionally, only 2.5 percent of waste was recycled, when that number should have been 15 percent.

John Dempsey, chair of Brookline’s Solid Waste Advisory Committee, said each year has looked better and better for lunch waste categorization.

“We see improvements and more and more kids composting every year,” Dempsey said. “A great number of kids are taking recycling seriously and that’s reduced our total waste by a lot.”

According to Dempsey, correct waste categorization is important. While contamination from other waste in the compost bins might seem like a small issue, it actually has major consequences.

“We’re doing pure industrial compost,” Dempsey said. “[The composting company] can’t abide by any type of contamination, so every time we find a plastic bag or a milk carton in the compost that is not biodegradable, we run the risk of losing the whole shipment.”

Social studies teacher and club co-adviser Roger Grande said ensuring the school’s compost is really composted is very important for our role in helping the environment. He said he believes composting is a simple yet effective method to battle climate change.

“The landfill is a less sustainable way to get rid of food-related waste, and we want to cultivate a culture of sustainability at Brookline High School,” Grande said. “[Composting is] a very easy and quick way to have an impact and divert the food waste stream into the compost stream and turn [food waste] into soil.”

Senior and club member Uma Zierten-Singleton said she was happy about the improvement over the past three years.

“There’s definitely more in the compost,” Zierten-Singleton said. “The first year we [sorted the waste], there was a lot less food that was composted.”

Dempsey said he is happy that composting is becoming a natural part of the school as more and more students take care to correctly separate their waste.

“When I’m watching lunch, kids naturally think of composting and they go up to separate their waste,” Dempsey said. “It warms my heart.”