Clean Water Current

(August 14, 2019) – EPA sent an August 6 letter to NACWA, the California Association of Sanitation Agencies (CASA), and two California utilities denying requested changes to the Renewable Fuel Standard (RFS) program that would help utilities to better manage food waste through anaerobic digesters. 

The RFS program offers incentives to produce renewable transportation fuels, including fuel produced from biosolids.  Biosolids-derived fuel is classified as a cellulosic biofuel, which carries a D3 Renewable Identification Number (RIN).  However, if food waste is added to anaerobic digesters to increase the production of biogas, all of the fuel produced will receive the D5 RIN for advanced biofuel unless the portion of biogas from food waste can be determined.  Since D3 RINs currently have a higher value than D5 RINs, utilities reduce their profits by receiving food waste at the digesters.  

This situation conflicts with EPA’s Winning with Food Waste initiative and the Department of Energy and EPA joint challenge to expand renewable energy production at wastewater treatment plants.  During a June 3 meeting, the water sector groups asked EPA to consider changes to its regulations that would encourage managing food waste and increasing renewable biogas production through anaerobic digestion at wastewater utilities.  The meeting resulted from a March 25 letter sent from CASA, NACWA, and two utilities to EPA Administrator Andrew Wheeler requesting his assistance in making changes to the RFS program related to food waste and biogas. 

During this meeting, EPA expressed an interest in finding a solution, but the August 6 letter states, “EPA explicitly considered this very issue in the 2014 Pathways II rulemaking… Having reached our decision in Pathways II through a robust notice and comment process, EPA does not intend [to] revisit this decision at this time.” 

NACWA will continue to work with CASA to find a practical method for determining the portions of biogas that receive the D3 cellulosic designation and the D5 advanced biofuel designation.  NACWA members that are interested in this issue are encouraged to contact Cynthia Finley, NACWA’s Director of Regulatory Affairs, for more information.