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9. ENVIRONMENTAL REPORT Biosolids Management Facility (BMF) Digested biosolids from the holding tanks are pumped through a 5.5-mile force main into one of four, 6.25-acre facultative sludge lagoons at the BMF. The lagoons are designed to maintain an aerobic layer free of scum or membrane-type film buildup. The aerobic layer is maintained by controlling annual organic lagoon loading at or below a critical area loading rate, and through use of surface mixers to agitate and mix the aerobic surface layer. The aerobic surface layer of the lagoons usually is between 1 and 3 feet deep and supports a dense population of algae. Dissolved oxygen is supplied to this layer by algal photosynthesis, by direct surface transfer from the atmosphere, and by the surface mixers. Sludge bacteria use the oxygen to aerobically degrade organic matter. Digested sludge solids settle to the bottom of the lagoons and continue decomposing anaerobically. Supernatant flows via 10-inch-diameter pipes to a sanitary sewer and is then conveyed to the WPCF (Management Plan for a Dedicated Biosolids Land Application Site [CH2M HILL, 2003]). Seasonal Industrial Waste Facility The SIWF is a 290-acre site with 190 acres of irrigated cropland and 25 acres of non-irrigated cropland. The total farmable area is approximately 215 acres. The site is located approximately 1 mile northeasterly from the BMF and 5 miles north of Eugene. It is currently developed with three 60-acre circles and one 16-acre circle of grass. The irrigation system consists of 1996 Pierce center pivots. A 14-acre, 57-MG storage lagoon is also located at the SIWF site. The lagoon no longer receives influent cannery waste but still contains residual waste from prior years influent. Potential future uses for the lagoon include effluent equalization/storage, BFP filtrate storage, and facultative sludge lagoon supernatant equalization/storage/treatment. The SIWF was built in 1983 to avoid high-strength organic waste loads into the WPCF on a seasonal basis. Since the purchase of the land by Eugene-Springfield, the SIWF has not been used for any land application or liquid storage of non-cannery wastewaters, as the site has been dedicated solely to irrigation of cannery wastewater. The land has been leased to a local farmer and forage producer to ensure that the site is continuously farmed using sound farm management practices. Biosolids Disposal - Biocycle Farm (Poplar Farm) The Biocycle Farm currently is in development. This facility is located next to the BMF and along Highway 99 between Awbrey Lane and Meadowview Road. The Biocycle Farm will provide MWMC with a land application site for beneficial recycling of biosolids. It is scheduled to be constructed in three phases and completed by 2008. Phase I will involve planting 160 acres of poplar trees and is scheduled to be operational by Summer 2004. Stabilized dewatered sludge from the BMF lagoons will be applied to the Biocycle Farm to provide the necessary nutrients for the poplar trees. This is anticipated to be the preferred method of biosolids reuse over the current practice of hauling to cooperative farms. Additionally, the Biocycle Farm will provide the flexibility to pump stabilized liquid sludge directly from the BMF lagoons to the Biocycle Farm for land application of liquid biosolids. MWMC 9.0 REV14.DOC 9-3