CORRESPONDENCE_4/7/22 [REV] APPENDICES W/FIRE PERMIT

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Forward Resource Recovery Facility WDR Technical Report HDR Engineering, Inc. 8 October 2021 3.0 Design Information 3.1 General Design Details The facility will receive up to 1,100 tons of organic material per day with up to to 200 TPD to the on-site ASP composting. The anticipated ratio of greenwaste to foodwaste in the feedstock is up to 15% foodwaste but can vary depending on market conditions. The process begins by mixing and pre-processing (sorting/chipping/grinding) the organic waste. The moisture content, particle size, porosity, and carbon/nitrogen ratio are adjusted to optimal conditions for the composting systems. The feedstock is placed either into the windrow or ASP composting system. The windrow composting period ranges from four to twelve weeks for the active phase, and one to six months for the curing phase. Each windrow compost pile has a length between 110 to 650 feet, a width of up to 18 feet at the base, and a height of up to eight (8) feet. The Facility uses a windrow turning machine to turn the windrows. ASP composting uses forced positive aeration through the pile. The typical active phase takes approximately four weeks, followed by another four weeks in the curing phase. The positive ASP composting method is recognized as a Best Available Control Technology in SJVAPCD due to its ability to reduce emissions by over 90 percent. A standard compost pile in the ASP is approximately 30 feet wide at the base, 100 feet long, and 10 feet in height. Each compost pile contains roughly 990 cubic yards of material. A compost cap is placed on top of the composting material to act as a biofilter. Temperature and aeration from the blowers are monitored throughout the composting process. As the composting process progresses, the volume of the material and mass of material is reduced through composting losses. After the composting process is complete, the compost product is screened, then stored on-site until it is moved off-site for uses such as soil nutrient amendment or trucked off-site to other markets such as agricultural. The Forward Resource Recovery Facility has approximately 39.1 acres designated for the facility (this includes access roads). The facility is located adjacent to an active landfill, Forward Inc. Landfill, which is not included in this Technical Report. The General Order requires all composting operations areas (material receiving, active, curing, and storage of finished compost) to be able to manage the 25-year, 24-hour storm. The compost pad and retention basin were designed by Lewis Engineering and were prepared to comply with requirements of WDR No. R5-2014-0006. Test results demonstrating compliance for the hydraulic conductivity requirements of the compost pad are included in Appendix C. Also included in Appendix C is the Compost Facility Storm Water Improvements Report from Lewis Engineering detailing the sizing of the retention basin. Lewis Engineering supporting calculations use 25-year, 24-hour and 25-year, 10-minute storm events to account for maximum peak flow. As described in the Lewis Engineering Stormwater Improvements Report, compost run-off water flows from the composting area to perimeter ditches which direct the runoff to two pond inlet pipes/culverts in the retention basin. The retention basin is designed to hold a total of 760,600 cf (approximately 5.7 million gallons or 17.4 acre-ft). Reducing the volume by 2-ft. of freeboard results in a capacity