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

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HAWAII COUNTY MECHANICAL - BIOLOGICAL TREATMENT FACILITY CONCEPTUAL DESIGN Health and safety measures should be incorporated into the design to mitigate operator fatigue and recordable injuries, and downtime due to human -error related incidents. Corrosion Protection Experience at several MBT and organic waste processing facilities over the past 15 years has highlighted the corrosive nature of the sorting and conversion processes when these processes are conducted in enclosed buildings or vessels. Therefore, all buildings and major equipment that will be come into contact with the organic material, process off - gasses, or other corrosive environments at the facilities should be designed and constructed using suitable materials or protective coatings to minimize corrosion. Site - specific environmental conditions (rainfall and volcanic emissions) should be taken into consideration when designing corrosion mitigation measures. Storm Water Management Storm water that has come in contact with feedstocks, or which has been contaminated by run- off from receiving, processing and product storage areas can be high in biochemical oxygen demand (BOD), suspended solids and /or nutrients. Storm water runoff and related regulatory compliance issues were a major factor contributing to the eventual shut down of the Unisyn facility on Oahu. In order to minimize the potential for contamination of surface waters (which in turn increases leachate management requirements), storm water from areas outside of the facility should be diverted around or away from the facilities through ditches, swales, berms or other conveyance methods. Similarly, drainage from building roofs should be controlled so that it does not enter or impede access to processing areas and buildings. All drainage controls and conveyances should be designed such that the potential for erosion and sediment transport is minimized. Use of filter berms, bioswales and erosion blankets constructed from compost should also be incorporated into drainage controls as necessary. Appropriate regulatory compliance plans for storm water and process water should be prepared for each facility. Process Water and Wastewater Management To control the impacts that could potentially result from the releases of contaminated surface water, run -off generated within each facility's receiving, processing, and curing areas should be collected and managed as leachate. Working surfaces in these areas should be constructed to withstanding expected wear and tear from site equipment and customer vehicles, and should be underlain by an impermeable layer to prevent downward and lateral migration of leachate into groundwater. Surplus process water that can not be recycled and reused within the process should be subjected to analytical testing, and could likely be managed in conjunction with leachate from the landfill operations. 13