Additional Digester Facilities Upgrades Project

Notice of Preparation of a Supplemental EIR for the Additional Digester Facilities Upgrades Project. The Project includes demolition of several existing structures within the Facility, including four existing digesters, to allow for construction of six new upgraded digesters. The new digesters, shown in the rendering on Figure 4, would include digester covers, an upgraded gas mixing system, structural upgrades, and necessary piping and accessories (e.g., security lighting). Additional structures to be constructed as part of the Project include a new electrical building, two new digester overflow/stormwater pump stations, and associated overflow/stormwater pipelines. Fats, Oils, and Grease Receiving Facility. The Project would include a new medium-sized Fats, Oils, and Grease (FOG) receiving facility to receive and process FOG materials that are trucked to the Facility. Refer to Figures 2 and 4 for the potential location of the new facility. The FOG receiving facility would improve overall Facility power efficiency. The FOG material would be blended with co-thickened sludge and then pumped to the digesters. The FOG receiving facility would accommodate off-loading of tanker trucks within a concrete containment area. There would be two FOG tanks provided for temporary storage before FOG material is distributed. Security lighting would be installed at each FOG tank and odor treatment would be provided for potential odorous air from the FOG storage tanks using activated carbon treatment units or similar technology. Site improvements such as rock landscaping, paving and grading, signage, street lighting, and exterior lights on existing tanks and inside the existing polymer storage area would be included as part of the Project.