4/26/2011 SEWER COMMISSION Minutes

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Page 29 systems that have higher accumulation rates while providing cost efficiencies by extending pump-outs for systems with lower accumulation rates. Some studies have found that managed STEP tank pump-out programs can achieve pump-out intervals in excess of 10 years. Many STEP systems are serviced with equipment that is unnecessary with regards to the maintenance tasks being performed, employee scheduling that is excessive, and with maintenance task scheduling that unnecessarily creates overtime costs. STEP systems can be maintained with basic tools like a small pick-up truck with a mounted suction pump, minimal product, component, and tool inventory that reflect those components that wear out more readily, and most tasks can be performed by a single service technician. It is not atypical for a single technician with a pick-up truck and a spare component inventory of about 5% of those in service to maintain more than 2000 STEP connections. Public education is an important tool with respect to 0&M. New customers should be given guidance that explains their wastewater collection system, along with the do's and don'ts that they must adhere to when using their wastewater facilities. Annual mailers to existing customers should be utilized to provide ongoing reminders of the initial guidance. When system alarms are attributable to misuse or a lack of knowledge regarding their system, service employees should be prepared to provide additional training to the customer through direct contact, door hangers or follow-up calls. In time, all components of a wastewater collection system will require renewal or replacement(R&R). R&R is an important element to consider when determining the life cycle cost or the best value of a wastewater collection system. The largest repair and replacvement(R&R) cost for any wastewater collection systems that utilize on- site pumps is typically related to the pump and controls.A high quality STEP multi-stage effluent pump will include warranties of up to 5 years. The actual pump/control life is highly variable, but some studies have suggested that they can provide 20 years of service. Such a long service life may actually be encountered at a specific location, but USEPA cost rules suggest use of no more than 10 years in the project planning stages. These pumps may feature a run-dry capability, a UL listing, a continuous operation listing. and may be manufactured from corrosion resistant materials.Additionally, pumps should be rebuildable when replaced, either by replacement of individual components or generally by replacement of either the liquid-end or the motor- end. While pumps are the main component of R&R, high quality tanks, filters, controls and discharge assemblies should not be compromised with the intent of simply shaving capital costs. When lower quality components are being considered, the designers should be required to evaluate any changes in R&R or 0&M costs in order to assure the owner that the R&R demands are acceptable and that the lowest life cycle cost is considered. Focusing on the major elements of a STEP system relative to construction, materials and 0&M is critical. If you are a perspective user of STEP, or if you are tasked with evaluating a STEP alternative, you need to try to separate 0&M data into those that apply to each available type of system,from both proper and less-demanding construction and management programs. Calling an existing STEP system operator and asking for their annual cost will rarely yield a reliable number without further investigation. If you are an existing STEP user, evaluate your own system against others to see if you believe it is properly constructed and maintained. A"properly constructed and maintained" STEP system will provide a sustainable and economical solution for wastewater collection. Life-Cycle Cost Considerations Upfront infrastructure costs,though important only represent a small fraction of the overall cost of a system. Life- cycle costs take all costs into account, which is particularly important for small communities, because small