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rrTNLS§2.2,3.1, SSS§2.1, 4.2. Properties to the north, south, east and west are currently inltural production, commercial/industrial and rural residential. Considering this area was farmed for decades,there is a significant potential for nitrate contamination of the underlying groundwater from nitrogen fertilizer applications and residual organic matter decomposition. However, nitrate testing conducted on the onsite well water indicates the nitrate-nitrogen concentration at low concentrations. It is assumed the depths of the onsite wells are comparatively deep and pumping water from deep aquifers that have not been impacted with nitrate. NLS§2.3, SSS§ 4.3,4.4,4.5,4.6. Since the winery is classified as a Small Public Water System, a water sample was not obtained from one of the onsite active domestic wells pursuant to EHD requirements. The EHD does require however, a California Drinking Water Watch document, found in Appendix D. This document lists all sources of onsite domestic water and their activity status. Calculation on the Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculations are contingent upon the environmental factors required for nitrification to occur. These conditions include soil pore-space oxygen content, soil temperature,pH, electrical conductivity, organic matter, cation exchange capacity,and alkalinity. Alkalinity in wastewater effluent is derived from the water source, in addition to the introduction of wastes. Nitrification consumes approximately 7.1 mg of alkalinity for every mg of ammonia- nitrogen(NH4 N)oxidized. Nitrification of the NH4-N concentration of 119 mg/L, as determined from the septic tank analysis, would require: 119 mg/L x 7.1 mg CaCO3 = 845 mg/L alkalinity. The alkalinity in the well water is approximately 72 mg/L. The alkalinity determined from the Administration Building septic tank effluent sample was 522 mg/L. 72+ 522=594 mg/L alkalinity. Therefore, an approximate deficient value of 845 mg/L - 594 mg/L=251 mg/L of additional alkalinity must come from the soil, or other sources,to provide a sufficient concentration for nitrification of the effluent. This has obviously occurred at the deeper soil depths as revealed in the backhoe test pit soil samples. E. SURFACE WATER INFORMATION AND CALCULATIONS NLS§3.2. The subject facility occupies two full APN Parcels after a recent Lot Line Adjustment. For the Nitrate Loading Study, this acreage includes Parcel 1 in its entirety of 149.5 acres. This total acreage includes impervious areas of the winery facility consisting of buildings, tank farms, paved areas, etc. and composes 83.7 acres of the total acreage. The solar panel farm, vineyards, stormwater pond, grass/trees and open areas, etc.,total 65.6 acres and is classified as pervious. The following Mass Balance Approach utilizes these referenced area delineations correlated with Available Rainfall and Net Rainfall Recharge: Page -5- Chesney Consulthig