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St.Jorge Winery Page 3 of 5 Soil Suitability/Nitrate Loading Study Update Our Project Number: MAISS039 September 23,2015 Table 3. Updated Weighted Average of Residential /Employee & Customer Total Nitrogen Concentration 45 mg/L-N x 490 gpd = 22,050 mg/L-gpd 65 mg/L-N x 279 gpd = 18,135 mg/L-gpd 22,050 mg/L-gpd + 18,135 mg/L-gpd = 40,185 mg/L-gpd 40,185 mg/L-gpd /769 gpd = 52.26 mg/L-N Based on the weighted average of mg/L-N concentrations in the flow of waste water, it is estimated that the average concentration for total nitrogen from both sources in waste water for the subject project is approximately 52.26 mg/L-N over the long term. A new nitrate loading scenario was performed to determine the impact from the proposed project. The scenario utilizes the variable discussed previously which represent the estimated conditions and uses associated with this project. The following table presents a summary of the nitrate loading calculation for the subject property. Table 4. Updated Summary of Nitrate Mass Balance Analysis Result Acres Average Daily Effluent Leachfield Deep (Nc)'(mg/L- A Flow(Q)(Table 2) Concentration Denitrification percolation of N) ( ) (gpd) (Nw) (mg/L-N) (d) Rainfall (R) (in.) 4.92 mcontaminant 10 769 52.26 5.29 Maximum contaminant level(MCL)for nitrate in drinking water is 10 mg/L-N. As is illustrated in the foregoing update, the additional usage will not raise the nitrate concentration to above the MCL. Therefore, the impact as projected will not negatively impact the subject property. Septic System The existing septic system consists of a 2,000 gallon tank with two (2) 100-foot leach line with a 2 feet by 20 feet by 10 feet deep sump at the end of each leach line. The following table presents the maximum average daily flow daily based on a single event which occurs 12 times out of a year on a weekend. "44 02015 Neil O.Anderson&Associates,Inc.A Temacon Company