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3-8 After the material passes through the grinder, it is dropped onto a conveyor that moves the material past a magnetic separator. A magnetic separator is provided to extract nails and other ferrous contaminants from the material. The shredded waste is moved by the front end loader to the composting area or loaded into a dump truck that will transport the material to the composting area where it is combined with other feedstocks. The waste materials are formed into compost piles which are up to approximately 15 feet wide by 7 feet tall at center, and of varying lengths up to 300 feet. The active compost will be mixed, as required, for proper control depending on temperature and moisture profiles and season (turning will be kept to a minimum during the rainy season). The frequency of the Windrow turning and water addition will be determined by monitoring the pile temperature and moisture content. Temperatures within the active compost are monitored daily using hand-held temperature probes. This information is recorded and records are maintained at the facility. Moisture content is monitored based on incoming moisture content, moisture addition, and by manual and laboratory testing. Piles are watered and/or turned based on the results of monitoring. All operating standards defined by State composting regulations are followed. As the materials (including water) in the active compost age, the volume of the compost decreases. Windrows will be combined with neighboring Windrows to maintain the desired pile dimensions. The final material is screened according to market specifications. Screened material is stockpiled on the site prior to loadout to markets or for on-site uses. Oversized materials (overs) from the screening process is reground, sold, or landfilled. b. Quench or Process Water Although this alternative is not currently used, the water collected in the runoff sedimentation basin may be used as process water to meet the desired moisture contents for composting. Water from the sedimentation basin may be applied to the waste, on an as needed basis and as available, as it leaves the tub grinder. A fixed nozzle will spray the water on the processed (ground) feedstock material (e.g., green and wood waste) at the discharge of the conveyor from the tub grinder. This process will eliminate the potential for pathogen regrowth in the active compost. The nozzle will not require contact with a human operator. If runoff water from the sedimentation pond is utilized, a pump system will be required to move water from the sedimentation basin to the tub grinder area. The rate of application of water will be determined to provide the desired final mixture moisture content. The primary source of process water at the RRF/Compost Facility is obtained from other on- site sources. Water for facility operations is supplied by four production wells. One well, located near the main entrance facility was drilled to a depth of approximately 135 feet and groundwater occurs at a depth of approximately 70 feet. The well was likely installed before the opening of the landfill, having been previously used for agricultural purposes. It is pumped at a rate of approximately 1500 gallons per minute (gpm) at a maximum frequency of approximately 27 times in a typical work day. Another well is located south of the South Fork of South Littlejohn's Creek, in the southeast corner of the RRF/Compost Facility area, and has a capacity of 500 gpm. The third well is located along the northern boundary of the former Austin Road Landfill. This well was installed in 1972 and has a production of approximately 60 gpm. The fact that groundwater flow near the existing Forward Landfill is not modified by pumping from this well suggests that it is screened in a confined unit below Forward Composting Facility SWT Engineering Report of Composting Site Information-November 2014 z:\prcjects\allied waste\forward\resource recovery facility\5 yr permit rvw 2013-14\resi 2014\text\9-nov 2014 track changes\sec 3.doc