Limitations on Organics in Landfills, State by State
Within the U. S., five states now have regulations to divert organics from landfills, including Massachusetts, Rhode Island, Connecticut, Vermont and California. This effort is largely focused on commercial waste, but Vermont includes residential sources, taking effect by 2020. Other states, including Florida, Maryland, Minnesota and New Jersey are also in various stages of adopting legislation to divert organics. Individual cities like Austin, New York City, Portland, San Francisco, and Seattle also have initiatives to divert organics.
California is the latest state to pass legislation, and at this spring’s BioCycle West Coast Conference in San Diego, various speakers proclaimed that existing infrastructure will accommodate as much as 75% of the organics. This capacity includes anaerobic digesters at water resource recovery facilities, which have the ability to not only process organics into biosolids for use as a soil amendment, but they can also produce energy from the biogas generated. So it seems logical that they will be a part of the solution.
Biogas – Too Much of a Good Thing?
But the expectation of processing organics at their facilities comes as a surprise to many treatment plant operators and managers. They consider their main task the protection of public health and the environment through wastewater processing in accordance with the EPA’s National Pollutant Discharge Elimination System. Processing organics is not a top priority when they already face challenges with biogas use. Obtaining air permits to burn biogas in internal combustion engines to produce energy is getting more difficult, and since feeding high strength waste to digesters such as food waste can significantly boost biogas production – 50% more from just 10% additional feedstock – these facilities will need to find a use for all this biogas.
Other alternatives for the additional biogas include making vehicle fuel in the form of compressed natural gas, or putting the gas into the pipeline. Both of these alternatives will require close collaboration among local governmental agencies and political officials.
The EIA released an Infographic in 2011 that brings to life the great versatility of biogas in modern society.
CalRecycle has placed the burden for compliance with the organics mandate on local municipalities through reporting that must be submitted in a couple of years. For organics generators, the current threshold of 8 cubic yards per week drops to 4 cubic yards in 2019, and to 2 cubic yards in 2021 if a 50% reduction from 2014 levels is not reached. Unless the use of biogas at water resource recovery facilities is somehow incentivized or subsidized by the local municipalities, where will all the organics actually end up?