Appendices to Integrated Resources & Solid Waste Management Plan - Dec 2009

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HAWAIH COUNTY MECHANICAL - BIOLOGICAL TREATMENT FACILITY CONCEPTUAL DESIGN State and federal regulations dealing with compost product quality tend to focus on protection of human and environmental health, and not on agronomic factors. These agronomic factors are generally defined by the marketplace, and include such things as pH, electrical conductivity, organic matter content, particle size, and water holding capacity. Agronomic factors often dictate the best use for a particular type of compost. Assuming that MMSW compost products produced in Hawaii County could meet applicable State and Federal requirements, it likely that sale and distribution would be more significantly affected by the agronomic standards of the marketplace. Although acceptable commercial and agricultural grade composts have been produced from MMSW, experience has shown that retail grade products are very difficult to produce from this feedstock. This is primarily because it is difficult to remove all of the man -made inert materials from the end product. Therefore, a MMSW compost product is typically less visually attractive than a more uniform yard trimmings or biosolids -based compost that does not contain fragments of inert materials. MMSW composts are also unable to be listed as a product for use in certified organic farming because of the feedstock materials it contains and the variety of feedstock sources. To increase consumer confidence in the product and improve marketability, the MMSW compost could be certified through the US Composting Council's Seal of Testing Assurance Program, with the appropriate analytical testing performed by certified laboratories. Two other Hawaiian composters (EKO systems in Maui, and Hawaiian Earth Products in Kapolei) already participating in this program. Design for Operability and Maintenance MBT facilities generally tend to have operating environments in which equipment is subject to a higher degree of wear and breakdown than in transfer stations and material recovery facilities. Flexibility and redundancy should therefore be incorporated into the layout and design of the facilities to allow operators to adjust for planned and unplanned maintenance, and unexpected surges in waste quantities. Flexibility and redundancy can be achieved through such features as the following: • Use of equipment with proven reliability. • Use of equipment which can be readily serviced locally. • Use of parallel processing lines to provide processing redundancy. • Cleaning the tipping floors daily. • "Decoupling" of pre - processing, processing, and post - processing operations where possible to allow for each process to operate independently and on different schedules. • Minimizing use of equipment that can not be replaced with relative ease and speed or for which parts are not locally available. Equipment should also be situated to conserve floor space and accommodate efficient vehicle access routes, personnel walkways, access stairs, and service platforms. Access and service platforms should be incorporated into equipment arrangements so that moving parts are readily accessible for inspection, maintenance, repair and /or replacement. 12