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Soil profile information is found on Page 4 and Table I. The UC Davis SOIL Web classified the proposed effluent receiving soils as a Veritas fine sandy loam. Percolation test data is also found on Page 4 with the perc test results found in Appendix C. III. NITRATE LOADING STUDY A. WASTEWATER FLOW VOLUME PROJECTIONS AND CHARACTERISTICS Wastewater Flow Volume Projections To determine nitrate-nitrogen loading from any project, wastewater flow volumes must be determined as accurately as possible. The volume of daily wastewater generation number of onsite people who will occupy each category of the subject property, after completion of the proposed Administration Building, is as follows: Fresh Cut Sweet Corn Processing: 20 people x 15 gals/person = 300 gpd x 250 work days/yr = 75,000 gals/yr Administration Building: 4 people x 30 gals/person = 120 gpd x 250 work days/yr = 30,000 gals/yr Modular Caretaker Homes (2 Bed): 100+50 = 150 gpd x 365 d/yr = 54,750gals/yr TOTAL = 159,750 gals/yr Wastewater Characteristics The domestic wastewater generated from the Facility will be composed of blackwater from tOilets and greywater from showers, laundry, hygiene, food prep, etc. The scientific literature cites domestic wastewater nitrogen concentrations to be anywhere from 35 mg/L to 45 mg/L N, and up to 62 mg/L. An average concentration of 45 mg/L will be used in the calculations below CALCULATED NITRATE-NITROGEN LOADING NLS§ 3.4, 3.5, 3.6. The calculated nitrate-nitrogen impact to the soil and potentially to the groundwater is difficult to determine due to the large number of variables involved and variables unknown at this time. These include: 1.) Nitrate impact from upgradient sources, 2.) Variability in wastewater flows, effluent nitrogen concentrations and dilution effects, 3.) Changes in groundwater directional flow and elevation, 4.) And the denitrification potential of the indigenous soils. HANTZSCHE/FINNEMORE EQUATION IN,„ (1 - + R Nb Nr = (I + R) Where: Nr = Resultant average concentration of nitrate-nitrogen in recharge water - (ppm NO,-N) I = Volume rate of wastewater entering the soil averaged over the gross developed area in in/yr Nw = Total nitrogen concentration of wastewater in mg N/L d = Fraction (%) of nitrate-nitrogen combined loss in the soil due to denitrification and prevention of nitrification. R = Estimated Annual Rainfall Recharge. Nb = Background nitrate-nitrogen concentration of rainfall recharge, exclusive of wastewater influences. Page -2- j Chesney Consulting