Resolution No. 4793 - Laserfiche WebLink

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t INTRODUCllON, PURPOSE AND NEED facility expand both its base secondary treatment capacity and its pr:anary treatment capacity for the plant to meet its NPDES permit. Regardless, the IViWMC adopted a WWFMP policy that facilities are to be constructed in order to increase the level of full secondary treatment from 103 mgd to 130 mgd. Current effluent blending policy is still evolving; however, blending now provides the most cost-effective approach to treating peak flows. A key underlying assumption in the preparation of this plan is that some level of effluent blending will continue to be an acceptable approach to treating the peak wet weather flows. If the DEQ does not accept this approach in reviewing this plan, contingency solutions that could be implemented are included and evaluated. However, the cost of these facilities would be significantly greater than those recommended in this plan. 1.6.3 Technology Drivers The original treatment facility was constructed in 1984, implementing the appropriate technologies of the era. New technologies have emerged since that time, and will continue to emerge to address both existing and future wastewater treatment needs. New technologies may have the advantage of providing better environmental results, providing more cost-effective treatment, lowering operational and maintenance requirements and costs, and other benefits. Technologies available for implementation today were evaluated as part of the planning process and are recommended where they meet cost-effectiveness, performance, and capacity criteria to meet the future regional wastewater treatment needs for MWMC's service area. 1.6.4 Existing WPGF ssues /% number of at the WPCF evaluated of the concerns were as part planning process to identify improvements to the existing facilities that would provide operational efficiencies, cost savings, reduced risks/liabilities, and improved worker and neighborhood safety. In some areas, the original capacity of equipment may now be limiting operations (influent pumping capacity is inadequate, screen trough sluice capacity is inadequate, etc.) Other needs are simply a result of aging or outdated equipment (i.e., pumps, valves, gates, communication systems, etc.). Process inefficiencies provide further bottlenecks to efficient operations (grease accumulation in influent screening conveyance, limited modes of operation in aeration basins, high operation and maintenance Lq the existing grit chambers, reduction in struvite scaling, etc.). Finally, the MWMC evaluated the current chlorine disinfection system and the available alternatives, and directed staff to include the conversion to a safer system using sodium hypochlorite. All of these needs must be addressed in order to provide the expansion capability necessary to meet future growth needs and to provide the most cost-effective and safe treatment facility operations. 1,7 Project Goa s and Objectives The goals of this Facilities Plan are to build on the previous planning efforts that have been ongoing since 1996 in order to develop a practical and cost-effective set of capital improvements necessary to meet community needs and minimum environmental standards for all MWMC facilities for the next 20 years. The Facilities Plan presents comprehensive and defensz~ble identification and evaluation of available capital improvement strategy alternatives, and recorrtrnendations that: MWMC_1.0_RE¥13 DOC