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Gea(ogxa1 Technus Inc Page 4 Groundwater Monitoring Report Project No 724 2 May 14,2002 ' samples were checked for heads ace bubbles, labeled, inserted into foam holders and laced p p into an ice chest cooled to 4°C for transport to the laboratory ' The sampling technician while collecting all samples,es, wore disposable gloves ' A chain of custody document, listing all samples collected and their intended analyses, accompanied the samples from field to the laboratory, thereby providing a means to track ' their movement and ensure their integrity 13 Laboratory Analyses ' The groundwater samples collected on March 12, 2002, were delivered to Sherwood Labs of Hilmar, California(certification #1400) for analyses of ' ! Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX), MTBE by EPA method 8020 • Total Petroleum Hydrocarbons as Gasoline (TPH-G) by EPA method 8015(M) ' The detection limits for the above analyses are listed in Table 4 of Appendix A, while the lab analytical results are presented in Appendix B As requited under AB2886, the laboratory data was submitted electronically to GeoTracker on April 26, 2002 - confirmation number 7829833269 ' 2.0 FINDINGS AND DISCUSSION The results of the groundwater sample analysis show the following Wells MW-1, MW-5, MW-6, MW-7 and MW-104 did not contain contaminant concentrations above the laboratory reporting limits • Well MW-2 has trace to low concentrations of the BTEX analytes • Wells MW-3 and MW-4 contain low concentrations of TPH-G or BTEX ' • In December 2001, well MW-7 contained trace BTEX constituents after four consecutive quarters of non-detect status For this event the well did not contain contaminant concentrations above the laboratory reporting limits ' • Intennediate wells MW-106 and MW-107 contained low BTEX concentrations and low to moderate TPH-G • For the sixth consecutive event deep well MW-104 did not contain contaminant concentrations above the laboratory reporting limits • TPH-G was not detected in any of the water table wells (MW-4 through MW-7) • TAH-G was detected in intennediate wells MW-2, MW-3, MW-106 and MW-107 Figure 5 — Interinediate Well TPH-G Concentrations - illustrates the extent of the TPH- G plume