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mixtures. The intent is to use the least complex and costly process that is found suitable for the feedstocks to be composted. The decision to construct a specific process will be based on economics. Design Parameters. The composting processes described later in this section all will be developed assuming that composting mixtures are developed for optimum composting and minimum odor generation. The parameters to be used are as follows: • Moisture content-50 to 60 percent • Carbon to nitrogen ratio (C:N)—greater than 25:1 • Density—less than 1,000 pounds per cubic yard • Porosity, structure—as necessary to maintain aerobic conditions The specific mixtures of feedstocks to achieve these parameters are impossible to calculate given the large number of potential feedstocks described in this permit application. The actual feedstocks available and the relative proportions will dictate the development of suitable mixtures. Temperature of the active compost will be monitored to comply with the State and Federal requirements to meet pathogen reduction criteria and also as required for sufficient process control. Moisture content of the active compost will also be monitored as necessary to provide for proper process control. Water Supply. Water for site operations is supplied by two on site production wells: a 1,000-gpm well near the landfill entrance facilities and a 20-gpm well near the RRF build- ing. There is a 8,000-gallon water tank located near the wood pile in the South area. In addition, water is available from the stormwater runoff retention pond. These water sup- plies are available for initial mixing of the compost to bring the water content up to desired levels, wetting of the compost, dust control, and other applications. Preprocessing. Preprocessing and initial handling of feedstocks is also common to the alternatives. Materials with large particle sizes such as wood waste, green material and agricultural wastes may require grinding before composting. These materials will be han- dled in the existing RRF and ground using the existing grinder. Additional grinding capac- ity will be added as necessary to handle the required volume of material. Green material ihigh in grass will be mixed as soon as possible with ground wood waste and/or recycled compost and/or other relatively dry and low C:N feedstock to minimize odor production. MSW preprocessing depends on the final use of the composted product. Little or no pre- processing is required if the compost is to be directly landfilled or used for landfill cover. Removal of large objects is necessary to prevent damage to Windrow turning equipment and grinding will aid decomposition during composting. Low technology Windrow com- posting of MSW has been successfully implemented in the U.S. If a higher quality product is desired, extensive preprocessing is necessary. This could consist of manual picking of metal, plastics and glass from the incoming material or receipt of source-separated waste. w&10029N4.ap5r26 9/28/94 26