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Proposed Cineplex Site Soil &Groundwater Sampling Repor. Page: 8 compounds, and halogenated compounds (solvents) by method 8260B. Analysis was conducted by GeoAnalytical Laboratories, Inc. in Modesto, California. 3.0 SITE GEOLOGY & GROUNDWATER OCCURRENCE The shallow sediments are composed of silts and clays, which grade into fine grained sands to the depth of the investigation. Perched water is present above a depth of ten feet, limited by weakly cemented sandy silt layer, in borings B-1 and B-2. Unconfined groundwater was encountered at an approximate depth of 13 feet in borings B-2, B-6, B-8, and B-9 clustered in the northern and northeastern portion of the area investigated. Semi-confined groundwater was present at depth of approximately 17 feet in the southern portion of the site in borings B-1, B-3, B-4, and B-5, confined by a silty clay encountered at a depth of 15 feet. A well-sorted silty unit is present as the confining layer in boring B-1. Groundwater was not encountered until a depth of greater than 20 feet in boring B-7 located in the northwest corner of the site. The source of the perched water present at shallow depths in borings B-1 and B-2 may be due to surface infiltration from seasonal rains and onsite activities. The unconfined to semi-confined water tables present in the fine sand unit at the base of borings B-2, B-6, B-8, and B-9 (water table at approximately 13 feet) and borings B-1, B-3, B-4, and B-5 (water table at approximately 17 feet) may be a single continuous aquifer influenced by the semi-permeable clay-silt layer present below ten feet in borings B-1, 13-3, B-4, and B-5. The relationship between the groundwater present at greater than 20 feet in boring B-7 and the groundwater encountered in the other borings can not be defined by this investigation. 4.0 CONCLUSIONS AND RECOMMENDATIONS The sample locations discussed above were surprisingly free of the most common contaminants included in the group of tests. However, diesel and oil along with low levels of chloroform were present in some of the samples. As mentioned above Chloroform can be a byproduct of chlorination such as for drinking water wells or swimming pools and it can also be a common laboratory contaminate when city waters are chlorinated. The Laboratory that analyzed these samples is on chlorinated City of Modesto water. The groundwater flow in this area, as referenced in the ENSR Report, is west to northwest. The concentrations are all within drinking water standards. Relatively high levels of oil were present in the 10 foot deep soil sample obtained from boring B-8 next to the Police Annex. The 20 foot soil sample and the groundwater sample from this boring were non-detect for oils and the other compounds. This boring was located about 15 feet from the American Savings Bank monitoring well MW-3 and is consistent with the soil contamination found associated with the Bank site. Closure of this adjacent property was approved by the CWQCB in April of 2000.