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rCAdJustments may have to be made to the future wastewater management system if unforeseen nditions dictate. For example, if wastewater flows are higher than projected in this Study, the septic system may have to be retrofitted with a dosing chamber and pump to dose the effluent out to the leachfield Monday through Friday when wastewater flows are nonexistent. Therefore, domestic water use for this project, and landscape water use within the leachfield areas, must be kept to a minimum because of the very slow permeability soil structure at leachline depth. Interior domestic water use can be accomplished with low flow toilets and spring-loaded fixtures in the sinks, as will be required. As referenced above and specified in the EHD Conditions of Approval, the existing septic system to serve the future office building is more than adequate. The acceptance rate calculations on Page I 1 show the leachline exclusively shall be sufficient to handle the effluent flows from this fixture office building and'given the fact that very permeable exists at seepage pit depth, this supplies confirmation that the existing system is adequate. To reiterate, this leachfield area must be maintained as a landscaped area and not paved over for parking. The application rate of the soil correlated with anticipated effluent flows reveals the following: 4 -65 ft sections of Icachl ine=260 lineal ft x 4 sq ft acceptance area/ft= 1040 sq ft total 1040 sq ft x 0.200 gals/sq ft/day= 208 gallons of effluent accepted/day 4 -48 inch diametef Wage pits=4 x 327 sq ft= 1306 sq ft total 1306 sq ft x (0.971 +0.671 gals/sq ft/day(from Table i)_2 =0.821 gals/sq ft/day, on average)_ 1072 gallons of effluent accepted/day The leachlines and seepage pits, as designated, can theoretically accept: 208 + 1072 = 1,280 gallons of effluent/day. This is equivalent to the projected maximum daily wastewater flows (1,250 gals) volumes, as calculated. l The new building should be built as high in elevation as practical and have the influent wastewater line plumbed through the building footing. This is to ensure that the septic tank is as high in elevation as possible so there is sufficient fall between the tank outlet and the furthest disposal point without exceeding the maximum allowable leachline depth. The architect, project plumber and septic system contractor must coordinate together on the construction details related to the septic system. Another source of nitrate loading can be from on-site lawns and landscaping, which is estimated to be 24% and could be significantly higher. It is recommended to use "slow release"nitrogen fertilizers on the lawns and landscaping to reduce nitrate loading from these areas. If nitrogen fertilizers are used, they should be applied under the package guidelines. To keep organic loading to a minimum, garbage disposals (grinders) should not be installed in the Church kitchen. Additionally, due to the indigenous clay soils, water softeners also should not be installed. The sodium liberated by water softeners will disperse and deflocculate the clay lattice soil structure and possibly render the clay soil impermeable. Regarding the nitrate-nitrogen loading to the underlying groundwater, it is important to recognize that when adding one concentration of a solute (e.g.,NO3 in wastewater recharge) to another concentration of a solute (e.g., NO;-N in groundwater),.where both solutes are in ppm, the result is not cumulative or the sum of the two solutes. I 13 l Chesney Consulting