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Composting Operation In Lodi, 40% of the residential refuse disposed of in landfills consists of leaves, grass clippings, shrub and tree trimmings, and other similar vegetative wastes. With a well planned and well managed plant waste composting program, most of this wasted resource can be economically converted to a product that has considerable value to the community and environment. Composting of mixed yard and garden waste provides a means of recovery of the inorganic and organic segments of the waste stream. Composting as a biological process in which the organic substances of solid waste are converted into a humus-like material. The compost, when added to soil, can improve the tilth, water, and nutrient holding capacity of the soil. Most composting operations consist of four basic stages: Front end processing, decomposition, curing and back end processing. Receiving, sorting, separation, size reduction, and moisture and nutrient addition may all be part of the front end processing stages. The two basic techniques used for the decomposition stage are windrow composting and enclosed vessel composting. Prepared yard and garden waste are places in elongated piles called windrows. The windrows are turned once or twice per week for a composting period of several weeks. The material is then cured for a minimum of 2 to 4 weeks to assure stabilization. The windrow system can be modified using the aerated static pile method. In this process, windrows of solid waste are developed on the tip of a piping network. The pipes are used to blow air through the piles. The advantage of this system is that the decomposition process occurs more quickly with a greater airflow. In enclosed vessels composting humus can be produced in 5 to 7 days. In some instances, composted material is cured in windrows for additional periods of 2 to 4 weeks. Composting is carried out by numerous microbial organisms in the solid waste that are either aerobic (requiring oxygen) or anaerobic. The material being processed should be thoroughly mixed and aerated to provide continuous aerobic conditions throughout the compost pile. Total Operating Capacity: Quantities of Material: As shown on page 9 of the DEIR the projected capacity of the composting operation is projected to be 49,000 tons per year of compost production. The current and projected breakdown of the types of material used in the composting operation is as follows: