Chances are you’ve used the College’s compost bins. But there’s an even bigger chance you’ve also thrown compost in the trash and trash in the compost. Sure, it’s difficult to sort your waste when the compost bins are halfway across campus, but this mistake is often made when the trash and compost are side by side.

I was curious why, when given easy access to the right bin, students still ended up using the wrong one. I observed students at a compost and trash bin location in Paresky for an hour during lunch. In total, 24 individuals incorrectly sorted their waste. From my observations and the following conversations, I deduced two key reasons why contamination persisted.

One reason for the contamination is a lack of education — some well-intentioned individuals are just uninformed. For example, one person hesitated in front of the bins, eventually composting their clamshell and recycling their cup. However, this clear cup, found in Goodrich and the dining halls, was actually compostable. Another individual thoughtfully put their skyr container inside their clamshell and composted them together.

Mistakes like these led me to wonder: What is actually compostable?

I talked with Mary Summers, the owner and one of two drivers of Tommy’s Compost Services, a local composting company the College works with, to learn more. She told me that items like peels, bones, leftover food, and napkins are compostable, so be sure to compost these!

Only commercial products with the BPI-certified compostable logo of a leaf and a tree in a circle are compostable. “BPI Compostable” refers to products certified by the Biodegradable Products Institute (BPI) as compostable. A product’s BPI certification mark signifies that it has been tested and complies with the ASTM D6400 or D6868 standards. These standards check how well a product breaks down in industrial composting facilities.

Such items include clamshell containers, clear cups, and utensils found in dining halls and Goodrich Coffee Bar. If it doesn’t have the logo, it won’t decompose! For example, items such as Snar receipts, yogurt containers, and printer paper are not compostable.

Summers explained that all compostable items undergo aerobic, meaning with oxygen, decomposition to become soil. This process requires a 3-to-1 carbon-to-nitrogen ratio to provide the proper fuel for microbes to produce the most nutrient-filled soil. While clamshells contain utilizable carbon, compostable clear cups do not; they are a “neutral” substance that decomposes but doesn’t actively contribute nutrients to the process. Despite this, Summers emphasizes that “it’s still more ideal than plastic.” So, if you must use single-use items, choose and compost these cups and utensils instead of their plastic alternatives!

The amount of commercially compostable items students use can also be too much for Tommy’s to handle. Senior Director of Dining and Auxiliary Operations Jeanette Kopczynski and Senior Operations Manager for Paresky Charlotte Clark told me that in the 2025-26 school year alone, the College used 317,000 clamshells, 257,000 clear cups, and 286,000 hot cups. That means that one student produces at least 400 items of single-use compostable waste in one school year. And this isn’t including the utensils, straws, plates, bowls, and lids that often come with these items.

So truly, only use clamshells when necessary; use a reusable plate or bowl instead! You can find the locations of dish return bins in the “Dining Services Collection Bins” tab found under the “Waste” subheading under “Sustainability” on the College’s interactive map.

While more can be done to raise awareness, through my conversations with students I found that most actually do understand how composting works, at least enough to generally know when items are incorrectly sorted. The biggest reason for contamination is that students are distracted. Twenty-two out of the 24 mess-ups I observed happened while students were talking to friends or rushing to class and simply seeking the nearest bin to get rid of their waste.

Sure, distraction, hastiness, and laziness as behaviors are problematic, but the greatest issue is the culture of rationalization surrounding these errors. If students know they’re doing something incorrectly, why do they do it anyway?

Perhaps you think it’s just one piece of waste — it’s no big deal if you incorrectly throw it away. But what about the 22 distracted individuals I witnessed who incorrectly sorted their waste in one hour at one location?

Just because it is out of sight does not mean that the waste no longer exists. With trash in the compost, there is always someone at the other end cleaning up our mistakes: The workers at Tommy’s Composting. What takes a student half a second to discard becomes the dirty work of another individual to find over the course of three to four weeks as these items attempt to decompose.

With compost in the trash, rather than existing in an oxygenated environment cultivated by the workers at Tommy’s, the compost is “suffocated” by the plastic trash. Instead of breaking down aerobically, these compostable items undergo anaerobic, meaning without oxygen, decomposition. A byproduct of this process is methane, a greenhouse gas that actively contributes to global warming. Overall, these mistakes contribute to a staggering 58% of the methane emissions produced by landfills.

I’m not trying to shame you; I know you’re busy. I am too and have made these mistakes as well. But just because we’ve made at least one mistake in our lives doesn’t mean we have to keep repeating them; we can choose to think for just one more second before we throw out our waste.

Let me offer an easy way to start: When you’re cleaning your fridge at the end of the semester, take the extra two minutes to walk to your nearest compost bin. They can be found in all dining halls, all libraries, outside the Zilkha Center, and in many more locations. You can find a comprehensive list by toggling the “Compost Collection Site” tab found under the “Waste” subheading under “Sustainability” on the College’s interactive map.

So, I’ll ask you. The College has compost bins. Are you using them?

Janet Dong ’29 is from Seattle, Wash.