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Ms. Christine Holm, ARU Kennedy/Jenks Consultants 19 December 1994 Page 2 • Groundwater samples from all five monitoring wells were analyzed for nitrate using EPA Method 300.0 (requested by the ARU). • Groundwater samples from MW-3 and 4 were analyzed for organo-phosphorous pesticides using EPA Method 614, chlorinated herbicides using EPA Method 615, Triazine herbicides using EPA Method 619 and Carbamate and Urea pesticides using EPA Method 632 (requested by the ARU). • A groundwater sample collected from MW-1 was analyzed for benzene, toluene, ethylbenzene and xylenes (BTEX) using EPA Method 8020/5030, for total petroleum hydrocarbons as diesel (TPH-d) and as gasoline (TPH-g) using EPA Modified method 8015 (requested by the USTU). LABORATORY ANALYSES RESULTS The groundwater samples were analyzed for the constituents of concern by Anlab and their sub-contracted laboratory, BSK Analytical Laboratories, of Sacramento, California. The laboratory analytical results are attached to this report as Appendix B. ARU Constituents of Concern Tables 2 and 3 contain the analytical results for nitrate and pesticides in groundwater samples collected from the five monitoring wells. A brief description of the analytical results is provided below. Table 2 shows the nitrate concentrations detected on Site. Monitoring wells MW-2, MW-3 and MW-5 contained nitrate at concentrations of 440, 97 and 62 mg/L above the California Maximum Contaminant Level (MCL) of 45 mg/L. Nitrate was not detected in MW-1 and MW-4 at concentrations exceeding MCL. In addition to nitrate, groundwater samples collected from monitoring wells MW-3 and MW-4 were analyzed for the presence of pesticides. Table 3 indicates the results of the analyses. Dinoseb, MCPA and Atrazine were the only constituents detected above relevant water quality criteria. The constituent 2,4,5-TP was detected at a concentration of 2.0 Ng/L which is lower than the California MCL level of 10 ,vg/L (USEPA MCL=50 pg/L). None of the other constituents were present above their detection limit. Additional groundwater samples collected from MW-3 and MW-4 were delivered to Anlab on behalf of the Central Valley Region Water Quality Control Board (CVRWQCB) for analysis. At the expense of the CVRWQCB, these samples were analyzed for chlorinated pesticides and PCBs using EPA Method 608. The analytical results for these constituents are also listed in Table 3. Constituents of concern were not detected above their detection limit at MW-4. Alpha-BHC, beta-BHC and gamma-BHC (Lindane) were detected at MW-3 at concentrations of 0.064 Ng/L, 0.14 pg/L, and 0.073 pg/L, respectively. Water quality goals for alpha-BHC and beta-BHC have not yet been established. The US EPA has, however, established an MCL of 0.2 ,ug/L for Lindane (California MCL=4ug/L). The concentration of Lindane detected in the groundwater sample from MW-3 is below the US EPA MCL value.