Laserfiche WebLink
- 19 - <br /> <br />e. Landfill Methane Recovery <br /> <br />This technology is similar to the clay digester except that <br />shredding and landfill design are not as important. Seven <br />landfills in the United States are currently recovering <br />methane. Landfill methane recovery is not an alternative to <br />landfill expansion unless shredding is employed or if humus is <br />recovered from the landfill. <br /> <br />Source-separated organics can be collected from citizens who sepa- <br />rate solid wastes and nonrecyclable paper from other components of <br />solid waste. Source separated organics provide an excellent feed <br />stock for composting since the material is relatively free of <br />glass, metal and plastics that reduce the value of the final com- <br />post product. Approximately 8,000 people in Portland, Oregon, <br />currently participate in such a program. Residents place food <br />waste and other organics in plastic pails with sealable tops.' The <br />pails are then taken to a site where the organics are composted. <br />When the compost is ready, area citizens use the compost for gar- <br />dening. <br /> <br />Composting of mixed waste is also feasible as an alternative to <br />land disposal. Altoona, Pennsylvania, and about 10 other cities <br />in the United States currently compost mixed waste. Mixed ~aste <br />includes not only food wastes and yard wastes, but also undesir- <br />able materials such as glass, metal and plastic. Mixed waste and <br />source-separated organics are both suitable for composting with <br />sewage sludge. Solid waste is a good bulking agent for sludge and <br />the sludge enhances the overall nutrient value of compost. <br /> <br />There are several examples of successful composting operations <br />currently in progress within the Region. Hennepin County and St. <br />Paul operate leaf composting sites as a free service to the <br />public. Leaves are deposited in the fall and compost mulch is <br />available for pickup in the spring. The City of Roseville pro- <br />vides free curb-side leaf pickup service for their residents <br />using specialized vacuum trucks. Their municipal composting site <br />is also available for drop-off and pickup similar to the St~ Paul <br />and Hennepin operations. Statewide leaf recycling programs <br />handle about nine percent of all yard waste generated (MPCA, <br />1979). The Metropolitan Waste Contral Commission has also been <br />windrowing filter cake sewage sludge from its Metro plant and re- <br />ports excellent success and more-than-adequate market demand for <br />the compost product. In general, composting has excellent poten- <br />tial as an alternative to landfilling organic wastes, depending on <br />final product quality and market demand. <br /> <br />Yard waste, on the average, represents 14 percent of the total <br />waste stream by volume, depending on the season. Some haulers <br />contend that in Minnesota, yard waste can increase the volume of <br />waste during spring and fall by as much as 50 percent (Beerman) <br />Since curb-side leaf pregrams don't require citizens to bag or box <br />yard waste, a high participation rate may be anticipate~ from a <br />well-run program. Based on recovery rate results of other pro- <br />grams, it is reasonable to assume that a 50 percent recovery rate <br /> <br /> <br />