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TABLE 2 <br /> PERCOLATION TEST RESULTS FOR THE PRIMARY DISPOSAL AREA WITH <br /> CORRESPONDING APPLICATION RATES IN GALLONS/FT2/DAY <br /> 36 INCH DEEP PERC TEST BORING 62.5 min/inch / 0.19 gallons/ftZ/day <br /> PERCOLATION RATE/APPLICATION RATE <br /> Application Rates adapted from Water Quality Control Policy for Siting,Design,Operation,and Maintenance of Onsite Wastewater Treatment Systems. <br /> I <br /> A GROUNDWATER INFORMATION <br /> NLS 2.1, SSS 4.1. Groundwater depths and elevations throughout San Joaquin County are <br /> illustrated on maps published by the County Flood Control and Water Conservation District. Lines <br /> of Equal Depth to Groundwater Maps for the year 2000 illustrate the depth to groundwater at <br /> approximately 15 ft. In 2018,the depth to groundwater was measured at 25 ft. The 2017 Lines of <br /> Equal Elevation indicate the groundwater directional flow to be in a north,northeasterly direction. <br /> NLS§2.2,3.1, SSS§ 2.1,4.2. Since surrounding properties have been intensely farmed for several <br /> decades,the potential for nitrate contamination in the underlying groundwater can be considered to <br /> be significant. However,the majority of farming operations have, and continue to occur north, or <br /> downgradient of the subject property. <br /> NLS§2.3, SSS§4.3,4.4, 4.5. The domestic well on the property was sampled and tested for the <br /> EHD required constituents of nitrate and the agrichemical Dibromochloropropane (DBCP),with <br /> the results in Appendix E. Test results reveal a nitrate nitrogen concentration of 4.8 ppm, or <br /> approximately half of the Maximum Contaminant Level (MCL), and Non Detect(ND) for DBCP. <br /> E. Climatic Data: Rainfall versus Evapotranspiration <br /> NLS§3.2. The following Table illustrates rainfall and evapotranspiration for the Tracy area. <br /> Precipitation data was obtained from the Soil Survey of San Joaquin County. The conservative"2 <br /> years in 10" data was used and not the"average rainfall" data. Evapotranspiration data was <br /> obtained from the California Irrigation Management Information System (CIMIS): <br /> TABLE 3 <br /> PRECIPITATION AND Eto DATA FOR TRACY, CA <br /> Month 2 Years in 10 will have more Eto Average Potential Deep <br /> precipitation than: (in/mo) (in/mo) (in/day) Percolation(in/mo) <br /> January 2.93 1.5.5 0.05 1.38 <br /> February 2.21 224 0.08 -- <br /> March 2.38 3.72 0.12 -- <br /> 4 <br /> Chesney Consulting <br /> 4 <br />