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Design Alternatives Alternative 1. Figure 4 shows the layout for Windrow composting using a front end loader to turn the compost piles. Feedstock requiring preprocessing or grinding would be unloaded and processed in the RRF area. Ground and processed feedstock would be moved to the composting area using front end loaders or dump trucks and placed into rough Windrows. Mixtures will be determined using volumetric proportions. Semi- solid and liquid feedstocks would be transported to the Windrow area and deposited directly on the rough Windrows. The quantity added would not exceed the quantity necessary to raise the moisture content to desirable limits. If semi-solid and liquid feedstocks are not available, water will be added using a water truck. The rough Windrows would then be mixed using front end loaders. After mixing, the Windrows would be formed in final configuration approximately 8 feet high and 16 feet wide at the base. Windrows would be turned as necessary to maintain aerobic conditions and for pathogen reduction in accordance with 14 CCR, Section 17868.3 based on 40 CFR, Part 503. Turning of Windrows would be using front end loaders. A 10-foot wide aisle is provided between pairs of Windrows to allow access for the front end loader for efficient turning. Initial turning frequency would depend on the specific mixture being composted, but would be approximately every 2 to 3 days for mixtures containing MSW, sludge, septic tank pumpings, and other highly putresible materials. The turning frequency would be much less for green material and wood waste - approximately once every 1 to 2 weeks. Later in the process depending on the composting period, the Windrows would be turned about every 2 to 4 weeks. Water would be added prior to turning as necessary using a water truck to maintain moisture at the desired levels. The composting period would be approximately 4 to 8 weeks depending on the quality of the product desired and the initial feedstock composition. Initially, Forward is planning to utilize this method as the primary alternative. Alternative 2. Figure 5 shows the layout for Windrow composting using a Windrow turner. The process is the same as described above except a Windrow turner would be used to mix the feedstocks, create the Windrows, and turn the Windrows. The Windrow dimensions proposed are approximately 8 feet high and approximately 18 feet wide at the base. The space between Windrows is about 8 feet to provide access for a water truck for water addition and for fire control. This alternative is considered Forward's back-up (or secondary method) if the need for additional composting capacity or the economics of using a Windrow machine justify the initial cost of the Windrow machine. Curing and Screening. Following composting, the mixture may be screened or placed in stockpiles approximately 10 feet high and approximately 20 feet wide at the base for curing. In curing, a slower rate of decomposition occurs. Curing time of approximately 1 to 6 months will be provided. A longer curing period is desirable for high quality compost. The curing period will depend on the quality desired and this in turn will depend on the market or final use of the product. The capacity of the composting site is significantly less to produce a higher quality compost product. After curing, the material may be screened. Screening produces a higher quality material, but at additional cost. Oversized material from screening may be returned for grinding, recycled to be used in the compost mixture or landfilled. Forward Composting Facility RCSI 7/20/09;Page 12 SWT Engineering