Microscopic bacteria eat trash, converting what we throw into the landfill to carbon dioxide, through the same process by which people produce carbon dioxide as we exhale. Other microorganisms that grow in landfills produce methane as an end-product of their specialized metabolism. Because of the lack of oxygen in landfills, methane is often the gas produced in abundance, so landfills are major contributors to increasing contributions of methane in our atmosphere. The trash that NAU sends to the Cinder Hills Landfill east of Flagstaff amounts to around 1% of NAU’s total greenhouse gas emissions. 
Mitigation: Solid waste is a small part of NAU’s greenhouse gas emissions, but reducing these emissions will have many other benefits as well, so it’s definitely worth a close look. For example, the more we recycle, the less goes to the landfill, having the double benefit of avoiding greenhouse gas emissions and saving usable materials (thus reducing society’s need to produce more). Clarifying NAU’s recycling program, and educating the NAU community to increase recycling rates, has thus been one of our major goals. We’re also examining the feasibility of turning the waste and greenhouse gas connection on its head – using methane emitted from the landfill itself to generate electricity (remember, methane is also known as natural gas, an important energy source…).