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►+ k`i KL E I N F E L D E R File No. 20-3937-01 September 3, 1996 1. Hydrocarbons were detected in two of the nineteen soil samples which were chemically analyzed. The sample obtained from 6-1/2 feet in boring B-2 (monitoring well MW-2) contained 0.0091 rng/kg ethylbenzene and 4.1 mg/kg TPH-Gas. Monitoring well MW-2 was located just south of the northern property line (near the former U. S. Chemical pond). Both of the concentrations attenuated to non-detectable levels by a depth of 11-1/2 feet. The concentrations present appear to be indicative of a limited surface spill of gasoline. r. Because of the low levels present, and the shallow extent of the hydrocarbons, Kleinfelder recommends no further investigation or clean-up by Schaeffer. However, regulatory concurrence should be obtained from either the RWQCB and/or the PHS/EHD. t.. A concentration of 0.026 mg/kg of xylenes were present in the soil sample obtained from a depth of 61 feet in boring B-3 (monitoring well MW-3). No detectable hydrocarbons were &W present in the soil samples obtained from 6', 11', 26', 41' and 56' in the same boring. This Y may be explained by the fact that the 61 foot sample was actually below the stabilized water surface in the completed well. Boring B-3 is located within approximately 25 feet of the Bobcat Central pond (up gradient). Therefore, the hydrocarbons may be indicative of hydrocarbons being transported in groundwater that adsorbed to the soil. Because it does not appear that these hydrocarbons originated on the proposed Schaeffer site, Kleinfelder does not recommend any further investigation or clean-up by Schaeffer. However, regulatory concurrence should be obtained from either the RWQCB and/or the PHS/EHD. 2. Asbestos was not detected in any of the four surface soil samples obtained near the railroad tracks at the northern edge of the site. 3. Sulfate was detected in the three groundwater samples obtained in concentrations ranging from 28 - 40 mg/l. There is no maximum contaminant level (MCL) expressed in Title 22 of the California Code of Regulations (22CCR). However, there are Secondary MCLs expressed in 22CCR §64449. The secondary MCLS (SMCLs) are 250 mg/l, recommended; 500 mg/I, upper; and 600 mg/l, short term. Therefore, these sulfate concentrations do not appear to be of concern. Additionally, the State of California Regional Water Quality Control Board (RWQCB) correspondence regarding the U.S. Chemical Site indicated that groundwater had not been affected by sulfate at the U.S. Chemical site. Therefore, Kleinfelder would recommend no further investigation or clean-up related to the sulfates. However, regulatory concurrence should be obtained from either the RWQCB and/or the PHS/EHD. 4. The only EPA Method 8260 analyte detected in any of the three groundwater samples �. obtained, was 18 pg/l (a.k.a. parts per billion or ppb) of 1,1-Diehl oroethylene in the sample obtained from monitoring well MW-2. Monitoring well MW-2 is located near the former location of the U. S. Chemical ponds which are north of the proposed �- Schaeffer site's northern property line. The concentration exceeds the maximum 20-3937-011AfR960189 Page 2 of 18 01996, Kleinfelder,Inc. L