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kq KLEINFELDER • 5 CONCLUSIONS AND RECOMMENDATIONS 5.1. CONCLUSIONS Kleinfelder observed the drilling and installation of eight groundwater monitoring wells (February 7 to February 14, 2006) within the shallow regional aquifer, in accordance with the local permitting agency (San Joaquin County EHD). The depth to water in the wells ranged from 78.86 feet bgs to 90.17 feet bgs. The groundwater elevations ranged from 33.02 feet MSL to 38.86 feet MSL. Based on the SJCFCWCD the groundwater flow direction at the site is towards the north/northeast, with a depressions noted to the north, east, and west of the site. The groundwater depressions likely influence the local groundwater flow on the site. The groundwater samples were collected, and analyzed for general minerals, wet chemistry, organics, bacteriological, radio chemistry, and dioxin. The detected concentrations of the analytes were compared to the MCLs set forth by the WQGs or • applicable guidelines established by the State of California Environmental Protection Agency and the United States Environmental Protection Agency. The initial water table groundwater quality showed the nitrate as NO3 concentrations seen in MW-2 (63.4 mg/L) and MW-4 (51.5 mg/L) were above PMCL for nitrate as NO3 of 45 mg/L. Nitrate is commonly associated with agricultural activities, and is a common groundwater contaminant where fertilizers are used and where livestock are present. Atrizine is a common pesticide and was detected with a concentration of 1.9 µg/L. The MCL for Atrazine is 1.0 µg/L. Diuron is a common herbicide, often used in combination with pesticides such as bromacil and hexazinone. Diuron, detected with a concentration of 0.2 µg/L, is used to control a wide variety of annual and perennial broadleaf and grassy weeds on non-crop areas and many agricultural crops such as fruit, cotton, sugar cane, alfalfa, and wheat. The SNARL for Diuron is 10 µg/L. Total Coliform bacteria may be used as an indicator that other potentially harmful bacteria may be present. The Maximum Contaminant Level Goal (MCLG) for total Coliform is zero organisms. Fecal Coliform has a variety of animal and human sources and is usually associated with animal feedlot operations and/or septic leachfield systems. Iron was detected in groundwater samples collected from MW-3, MW-4, MW-7, and • MW-9 with concentrations exceeding the California drinking water standards SMCL of 300 mg/L. SMCLs are aesthetic standards not typically related health risks. Page 16 of 20 63136.H01/ST06R312/JDZ:Iv April 7, 2006 ©2006 Kleinfelder, Inc. J