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rFaxntta ated nitrate loading concentration in the recharge effluent is calculated to be under the Contaminant Level (MCL) limit for nitrate in drinking water. The variables used in the ns above are conservative. For example, the use of 87 mg N/L, which was determined als ank effluent from the referenced Churches, is a much higher nitrogen a '0n than th se concentrations published in the sources referenced on Page 15, Table 10 oary Report. econdly, various researchers place the nitrogen reduction occurring in septic 10%to 200 . From the May 8, 2003 Symposium"Onsite Wastewater Treatment-Nitrogen ,"Dr. S Oakley of Chico State University states that"approximately 20%of the total enerated is removed in the septic tank."As noted above, no reduction in nitrogen concentration within the septic tanks was assigned in the calculations. C. SEPTIC SYSTEM OPERATIONAL PARAMETERS AND COMPONENTS OVERVIEW SSS 3.7. The design of the proposed pressurized filter bed septic system for the Multipurpose Buil ' g s based upon the factors of environmental protection, efficient operation, and disposal field longevity. Although the disposal area may be considered temporary since it is anticipated to be / operational for less than five years, it must be considered to be operational for an indefinite lifespan, since the EHD regards any installed decentralized wastewater disposal system to have an indefinite lifespan. An overview of the wastewater disposal system operation is as follows, and is depicted on the Site Plans: Beginning with the restroom west of the kitchen, influent from this restroom will gravity flow west into a single compartment, 1,200 gallon tank with an effluent filter. Influent from the kitchen will also gravity flow west into a 2,000 gallon, three-compartment interceptor tank, or grease trap tank. Effluent from these two tanks will join into a single, six-inch dia. ABS line to gravity flow around the west end of the Multipurpose Building, and connect to the first of three 2,000 gallon, single compartment tanks. Influent from the Mens's and Women's Restrooms will also enter this first, 2,000 gallon tank. Effluent from this first tank will then enter a second single compartment, 2,000 gallon tank. These two tanks must have a six-inch dia. connection near the floors of the tanks,per EHD require , effluent will vi ow into a 'rd, single compartment, 2,000 gallon tank. T ' will be the ump Chambe to pressurize the fi er beds. The Pump Chamb wi consist of enco Biotube® filtration,with Duplex Pump Sy em. The two pumps w' ] lterrtate between p ssurizing the tw separate filter b s, operating u er"on-demand"dose cyc se three tanks wi rovide s' ificant quiescent tr el distanc f approximately the lengths of three- 2,000 gallon tanks cceptable hydraulic residence time(HRT) to occur. By"on-demand"dosing of the effluent, this creates surge capacity within the tanks and extends hydraulic residence time. Effluent will be distributed equally during events and activities at the Multipurpose Building when demand occurs, and makes the system less complicated to operate for the Church. The filter bed arrangement will consist of Infiltrator® Chambers with the pressure lateral piping hanging from the tops of the chambers. Effluent will spray to the tops of the Chambers and trickle down the sidewalls to the soil-effluent interface. Six-inch louvers are located on each side of the Chambers to allow oxygen diffusion and potential effluent uptake by plant root structures that may extend to this depth. Page -12- Chesney Consulting