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Assigning the following parameters to be averaged to provide the ADF: 1.) 15 gallons per person who Assigning be parked in the total number of parking stalls, 2.) 150 gpd for each toilet, and 3.)A reasonable number of maximum toilet flushes: O 96 parking stalls x 15 gals assigned to one person parked in one stall= 1,440 gallons per day(gpd) ® 22 toilets x 150 gallons per toilet per day=3,300 gpd OO 6 flushes/hr/toilet x 22 toilets x 8 hrs/day= 1,056 flushes/day x 1.5 gals/flush= 1,584 gpd Average= 1,440+3,300 + 1,584=6,324=3 =2,108 gpd ADF COMMERCIAL WASTEWATER CHARACTERISTICS Primary wastewater constituents-of-concern found in septic tank effluent have influence over two important factors in the operation of an on-site wastewater disposal system: Soil effluent acceptance rates and nitrate-nitrogen impact. The Biochemical Oxygen Demand(BOD) test is the most common test used in wastewater analysis, but can be unreliable for determining organic matter in water. BOD is the amount of oxygen, expressed as mg/L or ppm, that bacteria take from water when they oxidize organic matter. To determine BOD, oxygen the bacteria uses is calculated by comparing the amount left at the end of 5 days with the known amount at the beginning. Adsorption and volatilization, followed by microbial degradation are the primary processes for removal of soluble organics. Total Suspended Solids (TSS) is the material retained on a standard glass-fiber filter disk. Suspended solids can be categorized as volatile or fixed suspended solids. TSS can create and enhance the biomat formation between the soil and effluent interface, thus restricting infiltration. The biomat, also referred to as a"clogging mat," is a biological, slimy substance which forms on the soil-effluent interface over time. This mat is composed mostly of aerobic and anaerobic bacteria and bacterial products consisting of polyuronides and polysaccharides. The biomat does have one beneficial property and that is removing approximately 10% of the nitrogen from gravity flow disposal systems. It is unknown how much, if any,biomat material forms under pressurized filter bed systems. Consequently, this 10%nitrogen removal figure will not be used in the nitrate loading calculations on Page 14 to reduce the calculated nitrate loading. Total Nitrogen is the summation of ammonia-nitrogen (NH4) and organic nitrogen(proteins, amino acids, enzymes). Since the septic tank is predominately anaerobic, nitrogen cannot exist in its oxidized state as nitrate for any length of time in the septic tank effluent, and if it does, it is quickly reduced to NO or NOZ. If nitrate existed in septic tank effluent, this would also be added to ammonium and organic nitrogen to arrive at Total Nitrogen. Although there is a restroom on the existing premises that serves the Tracy Cold Storage business, the septic tank could not be located to obtain a representative septic tank effluent sample. NLS§3.3 A sample from the on-site septic tank may not have been truly representative of a commercial system because of the low number of people who use, and have used, this septic system. Consequently, to quantify the anticipated nitrogen concentration for use in the nitrate loading calculations from the built-out Ice House project, effluent sample test results were obtained from another commercial facility in the Tracy area. These analytical test results (three total tests) were averaged to provide the concentrations found in Column 2, in Table 5 below. 12 Chesney Consulting