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The well was cycled for 15 minutes so that aquifer water and not stagnant well water was sampled. Water was sampled from the hose bibb on the east side of the pump house. A one pint plastic bottle was used for the nitrate analysis and a 100 ml sterilized plastic bottle was used for the bacteriological sample. The hose bibb was sterilized with a diluted bleach solution before sampling for the baeteriol 'cal sample. Three VOA bottles were used for DBCP analyses. These ive sample containers-were placed in a cooled ice chest after sampling, and then transported to A & Agricultural Laboratories in Modesto under the-attached Chain of Custody. The constituent tested were for nitrate,bacteriological (Total and Fecal Coliform), and DBCP, in compliance with EHD's request and under the California Uniform Retail Food Facilities Law (CURFFL). Test results revealed the presence of Total Coliform bacteria for the first sampling f event. Consequently, on November 6, 2007, the well was re-sampled for Total and Fecal Coliform using the same sterilization techniques. This sample also came back positive for the presence of Total Coliform. Finally, after sufficient well chlorination, the well was sampled on February 19.' 2008 and tested absent for Total Coliform. This will be discussed in the Conclusions Section of this report. The following table illustrates the test results: TABLE 4 UNDERLYING'GROUNDWATER ANALYSIS FROM�THEON-SITE DOMESTIGWELL:1f ANALYTE LEVEE F. MAXIMUM CONTAMINANT LEVEL{MCL) Nitrate 18 mglL 45 mglL� DBCP DL � .Q2 µ/L Bacteriological: Fecal: Absent Total and Fecal Coliform Total: Present Absent October 14,2007 Test Bacteriological: Fecal: Absent Absent Total and Fecal Coliform Total:Present November 6,2007 Test Bacteriological: Fecal:Not Tested Absent Total and Fecal Coliform Total:Absent February 19,2008 Test E. SURFACE WATER INFORMATION Storm water is managed by on-site retention. There should be no impact to percolating effluent water. Since the groundwater directional flow is north-northwest, percolating rainwater from runoff from the facility into the top aquifer mixing layer may create a dilution effect to the downgradient percolating septic system effluent. Another significant dilution effect may come from the aforementioned O.I.D. canal traversing the north and west boundaries of the subject property. Groundwater dilution effects can only be truly discerned with complicated groundwater monitoring and modeling. According to a scientific paper authored by Shaw and Turyk (1994), reduction of nitrate concentrations in groundwater can occur primarily through dispersion, or by percolating rainwater recharge. f 6 Chesney Consulting