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TABLE 2 PERCOLATION TEST RESULTS WITH CORRESPONDING SOIL TYPE, PERCOLATION RATE AND APPLICATION RATE IN GALLONS/FTZ/DAY 36 INCH DEEP PERC TEST BORING 83.3 min/inch / 0.123 gallons/ft-/day SANDY LOAM 126 INCH(10.5 FT)DEEP PERC TEST BORING 10.9 min/inch / 0.786 gallons/ft2/d7 LOAMY SAND D. GROUNDWATER INFORMATION NLS§2.1, SSS§4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The Lines of Equal Depth Maps indicates the depth to groundwater in the Spring of 2018 was 85 ft. The Well Log indicates the standing water level depth was 52 ft in April 1980, thus a 33 ft drop in 41 years. The Lines of Equal Elevation Maps indicate groundwater directional flow is in a northwesterly direction. NLS§2.2,3.1, SSS§2.1,4.2. Properties to the north, south, east and west are currently dairy, agricultural production and rural residential. Considering this area was farmed for decades,there is a potential for nitrate contamination of the water table as evidenced by the 23 ft deep soil sample. NLS§2.3, SSS§ 4.3,4.4,4.5,4.6. The domestic well that serves the residence of the Dairy owners was sampled for nitrate,the discontinued agrichemical DBCP/EDB and total alkalinity. The nitrate-nitrogen concentration is approximately one-half of the Maximum Contaminant Level (MCL) at 5.43 mg/L and DBCP/EDB was Non-Detect(ND). Total alkalinity was a low 123 mg/L as CaCO3. Calculation of Alkalinity Requirement for Nitrification The nitrate-nitrogen loading calculation results 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 on-site well water, in addition to the introduction of wastes in the effluent. Nitrification consumes approximately 7.1 mg of alkalinity for every mg of ammonia-nitrogen(NH4 N) oxidized. Nitrification of the average Total Nitrogen (TN) concentration of 62 mg/L, as determined below, would require: 62 mg/L NH4-N x 7.1 mg CaCO3 =440 mg/L alkalinity. Therefore, soil alkalinity and alkalinity from wastes must provide substantial additional alkalinity concentration for nitrification to occur. E. SURFACE WATER INFORMATION The rainfall recharge factor used in the Hantzsche-Finnemore equation below will be based upon water balance documentation from Norman Hantzsche found in Appendix F. This Water Balance Analysis of the Stockton area is applicable for this project. 4 Chesney Consulting