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The lateral piping was the next portion of the system to be observed. Threaded caps at the ends of each lateral risers were removed and a plumbing snake was inserted into the PVC piping. It appears that the laterals were installed with 90 degree elbows to the risers since it was not possible to push the snake any further then about three ft; the length of the riser. The lateral risers should have been installed with 90 degree sweep elbows,which would allow the snake to travel the distance of the laterals. The last portion of the wastewater management system to be evaluated was the actual mound. As referenced, construction details of the mound are unknown. Of critical importance is the fact that it appears that the mound has not experienced a"blow-out." This occurs when the permeability between the sand layer and the soil-effluent interface becomes clogged with biomat, as described below. The effluent has nowhere to travel except out the"toe"of the mound, which is where the mound meets the native soil. Excavations were conducted around the toe to investigate for seepage indicative of the start of a potential blow-out. No surface seepage of effluent was observed. CONCLUSIONS AND RECOMMENDATIONS The first question raised is in regards to the capacity of the two existing septic tanks. Specifically, is the first, single compartment tank of sufficient size to manage the projected increase in wastewater flows. From direct observation, it was noted that there was a substantial carryover of particulate matter from the first to the second tank. This would indicate inadequate hydraulic residence time within the first tank. However, upon closer inspection, it was determined that the simplex pumping arrangement was actually pulling particulate matter through the tanks based upon how the pump was situated within the second tank. Consequently, my design includes the addition of a third,two compartment tank of 1,200 gallon size to be installed after the second existing tank. Both original tanks can remain. The second compartment of this new tank will be the pump chamber. A new duplex pump system will be enclosed in a BioTube®, which has its own filtration mechanism. The duplex pumps will also allow alternating between these two pumps to prolong pump lifespan, and will allow the entire system to function in the event of single pump failure. There will also be a control panel that will alert the Church Staff of any malfunctions. The second observed concern, was the amount of biomat within the lateral risers. Biomat, also referred to as a clogging mat, is a slimy material composed mostly of aerobic and anaerobic bacteria and bacterial products consisting of polyuronides and polysaccharides. This biomat material was substantial, leading to the conclusion that it must be significantly present throughout the piping network, as well as throughout the mound. By installing an additional septic tank, this will allow for greater hydraulic residence time (HRT) and further treatment of the wastewater influent, thus theoretically mitigating biomat formation. The septic tanks should have a calculated, or direct observation pump-out schedule. Direct observation by a pumper company, is the most efficient method since the scum and sludge layers can actually be measured. When 25%30%of the tank volume consists of these two layers, the tank should be pumped. Page 3 of 4 Chesney Consulting