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Rausser Property Page 8 of 14 Our Project Number: E07121A August 8, 2007 4.3 Water Sample Location One well permit was found for the subject property which was issued in June of 1999. The permit was for the installation of a domestic well. A water sample was taken by - Jessen Welch of our office on April 18, 2007 from the spigot of the well on the property. 4.4 Water Sample Constituents The water sample was analyzed for nitrate and DBCP. DBCP was not detected in the water sample. Nitrate was found at 44.8 mg1L-NOJ slightly below the maximum - contaminant level (MCL) of 45 mg/L-NO3 set by the United States EPA. The analytical reports prepared by FGL Environmental can be found in the appendix of this report. Well construction, seals, age and depth of the well screens may play significant part in assessing the levels of Nitrate and DBCP in various aquifers. Without knowing specific details regarding well construction and condition, it would be difficult to accurately comment on the condition of the aquifer. Essentially, the water sample concentration approximately indicates the contaminant concentration level of the aquifer from which the well is drawing. It is Neil 0. Anderson and Associate's opinion that, in general, near surface aquifers are more likely to have elevated concentrations of Nitrate and DBCP than the deeper aquifers. However the contaminant concentration of one aquifer cannot give any indication as to the concentrations of any other aquifer regardless of proximity. The presence of nitrates is not uncommon in shallow ground water aquifers in San Joaquin County and other parts of the Central Valley. Nitrate in ground water occurs as a result of the application of fertilizers, livestock waste, and untreated septic tank waste. Nitrate is mobile and often accumulates in the shallow ground water zones. In the early 190Os, natural levels of nitrate in ground water were measured in forty- three (43) wells throughout the Sacramento Valley by Bryan (1923). It was thought that ground water at that time was close to "natural" conditions. Based on the work by Bryan, it is estimated that under "natural" conditions, the ground water concentration of nitrate is no more then about 13.5 mg/L-NO3 (3 mg/L-N). Areas having 24.75 mg/L-NO3 (5.5 mg/L-N) or more are those in which nitrate concentrations may be increasing (Hull, 1984). "04 902 Industrial Way•Lodi,CA 95240•209.367.3701 •Fax 209.369.4228 02007 Neil O.Anderson&Associates, Inc.