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i Mencarini Property P tel► Page 4 of 14 Our Project Number: LGS080538 August 26, 2008 approximately 30 and 45 feet below the ground surface. The groundwater in the vicinity of the i Site appears to flow to the south/southwest. No groundwater was encountered by the staff of Neil O. Anderson and Associates, Inc. during the drilling of an 8.5 foot groundwater boring on August 20, 2008. 1. Potential Groundwater Contamination Issues Identifying potential groundwater contamination sources was not part of the scope of work for the soil suitability study and nitrate loading study. Potential groundwater contamination can occur from a number of sources which often include leaky underground storage tanks, agricultural activities, dairies, septic systems, and storm water infiltration. Agricultural activities and the use of septic systems in the area should be considered potential ground-water contamination sources. vL4.3 Water Sample Location One (1) domestic well and one (1) agricultural well exist on the site. A well water sample was taken on December 7, 2006 by FGL from the domestic well on the Site. I 1.4.4 Water Sample Constituents I The water sample was analyzed for nitrate and DBCP. Nitrate was found at 31.6 mgLLN03 i which is below the maximum contaminant level (MCL) set by the US EPA of 45 mg/L-NO3. j DBCP was detected in the well water sample at a concentration_of 0.17 uq/L,_which is below the MCL set by the US EPA of 0.2 fag/L. The analytical reports prepared by FGL Environmental can be found in the appendix of this report. The presence of nitrates is not uncommon in shallow groundwater aquifers in San Joaquin County and other parts of the Central Valley. Nitrate in groundwater 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 groundwater zones. In the early 1900s, natural levels of nitrate in groundwater were measured in forty-three (43) wells throughout the Sacramento Valley by Kirk Bryan (1923). It was thought that groundwater at that time was close to "natural" conditions. Based on the work by Bryan, it is estimated that under "natural" conditions, groundwater concentration containing 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). DBCP was found in the water sample at a concentration of 0.17 pg/L, which is below the MCL set by the US EPA of 0.2 pg/L. DBCP is a nematocide and soil fumigant for vegetables and grapes. It is thought to cause health problems consisting of kidney damage, liver damage, and cancer. The use of DBCP was discontinued in 1979. I i 902 Industrial Way•Lodi,CA 95240.209.367.3701 -Fax 209.369.4228 (02008 Nei!O.Anderson&Associates,Inc