You are a responsible, environmentally conscious consumer. So when you walk into the sidewalk cafe that just opened down the street and see that your tasty to-go order is packed in a biodegradable container, your heart smiles and you decide you’ll become a regular. And after enjoying said tasty meal, you place your biodegradable container in the garbage and revel in the satisfaction that while your waste is landfill-bound, it will not be there for long. After all, isn’t that what makes biodegradable products so eco-friendly? They decompose quickly and that is good for the environment, right?
According to a new study released by North Carolina State University, maybe not. The study, entitled “Is Biodegradability a Desirable Attribute for Discarded Solid Waste? Perspectives from a National Landfill Greenhouse Gas Inventory Model” was conducted by Dr. Morton Barlaz and James Levis and was published by Environmental Science and Technology.
The results of the study reveal the simple fact that, under present conditions, because biodegradable materials decompose so quickly they may actually be harming the environment. This was, of course, supposed to be the great benefit of biodegradable materials. Unlike other plastics, papers, etc, biodegradable materials were developed to take up space in a landfill for only a very short amount of time. According to the EPA, in 2008 135 million metric tons of trash were dumped into landfills in the United States. America is currently home to well over 3000 active landfills and finding new places to discard our waste is becoming increasingly difficult. The assumption has, up until this point, been that biodegradable materials would help to ease our need for new landfills.
So what is happening to biodegradable waste once it reaches the landfills that makes it harmful to the environment? During decomposition, biodegradable materials release methane. Methane is a very potent greenhouse gas- though it is not as prevalent as carbon dioxide, it does more damage. However, methane can also be harnessed and burned for fuel and it burns much cleaner than many other natural gasses. In the United States, approximately 35% of landfills capture methane onsite and use it for energy, while another 34% of landfills capture the methane and burn it offsite. The problem is that current government regulations do not require land fill operators to harvest methane for energy until two years after the trash has been discarded. When you combine that with the Federal Trade Commission’s requirement that biodegradable products must decompose within a “reasonably short period of time” the result is that too much methane is being released into the atmosphere. By the time methane capturing techniques are put in place in a landfill, the biodegradable materials have already decomposed significantly.
Fortunately, the problem is fixable. Manufacturers of biodegradable materials could develop and produce materials that decompose more slowly. These products would still decompose faster than conventional products, thus reducing the volume of our landfills, but slow enough that most of the resulting methane could be captured. Alternatively, the government could alter existing regulations. If landfills were required to harvest methane immediately after burying trash, no methane would be left to waft into the atmosphere.
Photo credit: stlouiscountymn.gov/GOVERNMENT/Licensing/GarbageHaulerLicenses.aspx