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7TThedesignineer specified two - 1,600 gallon tanks that were installed in a configuration eries." This refers to an arrangement where influent(raw sewage) enters the first s specified as a single compartment tank, with effluent gravity flowing to the Solid and liquid wastes separate into sludge, scum and clarified layers. The waste sludge is digested in this tank. Clarified effluent then gravity flows into the second, two-compartment tank for further treatment. A simplex (a single)pump was installed in the second compartment of the second tank to pressurize the effluent for dispersal to the soil. The simplex pump pressurizes the effluent through a 2-inch force main pipe to a center-feed manifold arrangement that has five equal-distant,perforated laterals connected to the manifold. The pressurized effluent then is discharged through the lateral orifices traveling into the drainage absorption area. Typically, mounds are designed with drain rock which overlays sand filtration. Since no plans or specifications were found at EHD regarding the design and construction details of the mound itself, it is unknown how it was constructed. Design parameters should have been based upon the information and criteria needed to design a mound at that point in time. MATERIALS AND METHODS The beginning approach to assessing the existing wastewater management system was to adequately characterize all sources of wastes and wastewater flows. From the attached Demographics page, it is apparent there are waste flows all through each week,just not primarily on Sundays. The influent piping consists of six-inch dia. PVC,which is above adequate size, with clean-outs spaced appropriately. The influent waste stream enters the first, single compartment, 1,600 gallon septic tank. This tank was observed for structural integrity around the manhole cover, which is typically the first sign of concrete decomposition. This decomposition occurs from the formation of hydrogen sulfide gas from the decomposing wastes. The area of the tank appears to be structurally sound. The second tank was inaccessible but is assumed to be sound also. The second tank in series is a two compartment, 1,600 gallon capacity tank. The second compartment within this tank is the pump chamber with a simplex pump. After removing the cover lid,this pump arrangement was directly observed and found to substantially antiquated and inadequate. Current Codes require a duplex (two)pump system. The electrical connection is situated within the pump chamber where it could be exposed to water. There are two methods to pressurize the effluent from the last septic tank using duplex pumps; time dose or on-demand dose. I have designed the effluent pressurization to operate under demand dose which is discussed in the Studies and Design Report. Page 2 of 4 Chesney Consulting