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LOGE 1714: Delicato SS/NLS Addendum Page 6 July 18, 2017 Table 3. Average Daily Flow Calculation Use Units Rate Subtotal Reduction* Average Daily Flow Houses 3 140 gal/bedroom 420 gpd none 420 gpd (existing) bedroom Winery Staff 391 staff 13 gal/staff 5,083 gpd none 5,083 gpd Tasting 119 3 gal/customer 357 gpd none 357 gpd Room Customers Event 86 5 gal/customer 430 gpd 10/365 11.8 gpd Customers Total 5,871.8 gpd *Reduction factors convert calculated flow into average daily flow over a year; 10/365 converts for events per year. Table 4. Weighted Average Concentration Calculation Use Average Daily Estimated Waste Weighted Average Flow Water Quality Product Existing Residence 420 gpd 35 mg/L-N 14,700 gpd-mg/L-N Winery Staff 5,083 gpd 85 mg/L-N 432,055 gpd-mg/L-N Tasting Room Customers 357 gpd 85 mg/L-N 30,345 gpd-mg/L-N Event Customers 11.8 gpd 85 mg/L-N 1,003 gpd-mg/L-N Totals 5,871.8 gpd 478,103 gpd-mg/L-N Weighted Average 478,103 gpd-mg/L-N / 5,871.8 gpd = 81.4 mg/L-N Concentration: Denitrification Reductions Denitrification is a process that occurs in the septic system drain field whereby certain bacteria oxidize the nitrate (NO3) in the wastewater and release nitrogen gas (NUJ to the atmosphere. Due to the biologic processes in the shallow soils, nitrogen in the drain field may undergo a reduction between 10 percent to 35 percent. Soils with higher clay content, moist soil conditions, high pH, and organic material denitrify by about 35 percent, and soils with high sand content and fast percolation rates tend to denitrify at a lower rate of about 10 percent. A denitrification factor of 20 percent was selected for the Site because the soils examined were a combination of silt and sand.