Hixon Notes: Let’s Talk Trash

The Hixon Center’s Waste Audit offers Insights and Opportunities to Reduce Waste at Harvey Mudd

By: Prof. Tanja Srebotnjak & Louis Spanias

Students sorting through HMC's trash.

Trash is one of the most overlooked aspects of our lives. The average American generates about 4.3 pounds (lbs.) of waste per day [1]. It doesn’t sound like a whole lot, but for our student body this equates to approximately 3,440 pounds of garbage daily. That’s a lot of trash, and most of us don’t even know where it goes.

In truth, more than half of what we throw away ends up in landfills.[2] In many cases, that includes items that could be reused, recycled or composted. Most of us have never seen a landfill up close, which explains in part how we think about waste: the moment a material becomes trash to us, we expel it from our lives – never thinking about what will happen to it.

This “out of sight, out of mind” attitude has consequences – for the planet, for our health, and the economy. Municipal solid waste landfills are the third largest anthropogenic emitter of methane – a highly potent greenhouse gas with a global warming potential that is 25-86 times greater than carbon dioxide (depending on the time horizon). In fact, methane from landfills accounts for about 15.3% of all anthropogenic methane emissions. [5]

Trash in landfills

There are over 3,000 active landfills in the United States. [3] Image: Think, Act, Prosper Blog [4]

With that said, addressing climate change will require us to divert waste from landfills and reduce methane emissions. Landfills also pose risks to public health via sub-surface migration of landfill gas and leachate into groundwater systems, surface emissions of carbon dioxide, methane, volatile organic compounds (VOCs), and hazardous air pollutants (HAPs), and strong, pungent odors that present quality-of-life concerns.[6] Economically, waste is also a lost opportunity, as we are disposing of nutrients from organic waste, as well as reusable and recyclable materials.

Waste, therefore, presents a substantial opportunity for Harvey Mudd College to combine sustainability practice with research and education. The Hixon Center for Sustainable Environmental Design started conducting campus waste audits in November 2015. An initial sample of 110 lbs. from various campus buildings determined that more than 70% of waste (by weight) could be diverted from landfills to compost or recycle streams.


On April 8th, the Hixon Center followed up with a larger waste audit. With the help of Facilities and Maintenance (F&M), Hoch-Shanahan Dining Staff, and student volunteers, the Center sorted through nearly 620 lbs. of trash from academic facilities (Shanahan Math, Parsons Engineering), classrooms (Shanahan), dining (Hoch-Shanahan), and residence halls (Drinkward, Sontag).

The results confirm our earlier findings about Harvey Mudd’s diversion potential: nearly 530 lbs. (86%) of the waste (by weight) could be diverted from landfills. Organic and biodegradable made up 48% of the waste, and recyclables 38%, leaving only 14% for the landfill. The biggest opportunity to compost comes from the Dining Hall’s organic waste, and most recyclable waste originated from academic and residential facilities. You can view the full results of the waste audit in a complete presentation.

HCSED April Waste Audit
We believe that the Harvey Mudd Community agrees that we should reap the environmental, health, and economic benefits of waste reduction. There are a number of ways in which the College can take action. For example, we are exploring options to bring a more comprehensive and consistent system of waste bins to campus and are collaborating with F&M and the Dining Hall to divert organic waste to composting by 2017. Better access to clearly labeled recycling and composting bins on campus will make it easier for all of us to properly sort through our waste.


However, there is more that we can do: the best way to divert waste from landfills is to limit waste generation in the first place. Here are a few ways to get started:

  • Plastic/Paper Cups and Bottles – Most dining facilities on and off campus offer disposable to-go options, but you do not need them. Bring your own water canteen or mug/thermos and prevent disposable materials from going into the trash.
  • Printing – The waste audit revealed that a lot of paper gets thrown away, but you can substantially reduce your paper waste by reading and annotating documents on your computer, by printing on both sides and using single-sided printed paper as scrap paper.
  • Go for second and third helpings – Our eyes are often bigger than our stomachs. Start with a smaller portion and go back for seconds (or thirds) if you want.
  • Avoid single-use plastics – Avoid purchasing or using anything that is wrapped or packaged in plastic that can’t be used again (e.g. plastic-wrapped utensils, packaged materials from office or convenience stores, etc.).

[1] https://center.sustainability.duke.edu/resources/green-facts-consumers/how-much-do-we-waste-daily

[2] https://center.sustainability.duke.edu/resources/green-facts-consumers/how-much-do-we-waste-daily

[3] http://www.zerowasteamerica.org/landfills.htm

[4] http://thinkactprosper.blogspot.com/2011/09/green-garbage.html

[5] https://www3.epa.gov/lmop/basic-info/

[6] https://www3.epa.gov/lmop/faq/public.html