COM 0272.002 1996-1998 - Laserfiche WebLink

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effective solid waste management diversion goals are just that, goals, and other factors such as long term trends in collection systems and material processing the potential for local job creation should be considered. It is extremely difficult to accurately compare projected diversion rates between mixed waste processing facilities and source separated MRFs. "Dirty MRFs" often claim diversion rates as high as 70% of the entire waste stream yet the actual diversion of recyclable material is rarely over 15%. The balance of the proposed diversion comes from the production of a MSW compost or a Refuse Derived Fuel. In addition, as the facility must be designed to manage the entire waste stream, its capacity and the resulting capital cost is often 4 to 5 times that of a source separated MRF which is sized only to process the primary recyclables in the waste stream. Source separated MRFs on the other hand may recover over 95% of the material entering the facility, but only require capacity to process that material which the community has previously segregated. This results in much lower capital and operating costs and the ability to construct a facility in increments, sizing it to fit the community's needs over time. Cfean MRFs are labor intensive operations, which allow a smaller scale, low tech approach, and focus on marketing a high quality material. They can provide economic development opportunities to the local community, and allow flexibility in meeting changing waste management and market requirements. While the diversion rate (as a percentage of the total waste stream) of a source separated MRF, is dependent upon the participation of the community, many communities have experienced a 35% to 40% diversion rate with aggressive promotion. Although the current proposal for a mixed waste processing facility estimates a 65% diversion rate, the bulk of the diversion (50%) would be a low grade compost comprised of dirt, grit, foodwaste and grass clippings and contaminated by chemicals, and plastic, glass and metal particles. The recycled material would be glass and metal containers of low quality, and paper and plastic contaminated with garbage & liquids. The market for small quantities of contaminated recyclables is extremely limited, so the facility would either have to give the material away or invest additional time and equipment in further processing. Initially the overall diversion projected by mixed waste processors may be a strong selling point when an instant solution to a complex problem is desired; but upon investigation of the higher costs of construction and operation and the difficulties other communities have faced in marketing their mixed waste compost (or the retrofiting existing boiler units to burn a RDF), it is often found that a large part of the diverted material ends up as expensive landfill cover. Mixed waste processing facilities are high capital cost projects, that focus on simplistic approach to managing a extremely heterogeneous waste stream. They have major processing requirements, complex mechanical systems and greater problems and liabilities regarding worker health and safety. It is often difficult to develop long term, stable markets for their materials and they have a limited ability in adapting to changing market requirements.