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Monitoring Wells MW#4S and MW#4D were installed on the east side of Wilson Way in September of 2000 Also, monitoring wells MW#5D, MW46S and MW#6D, MW#7S and MW#7D were installed north and south of the pump islands in September of 2000 (see attached Site Map) Monitoring wells MW#8S and MW813 were installed in a single bore hole inside the existing building, west of the pump islands on October 3, 2000 Fourth QUARTER 2000 MONITORING WELL SAMPLE ANALYSIS REPORT Sampled 10/09/2000 WATER ANALYSIS OF SAMPLES FROM MONITORING WELLS On December 21, 2000, Del-Tech Geotechnical Support Services extracted water samples from each monitoring well using standaid industry practices under the supervision of Foothill Engineering A report of this work by Del-Tech Geotechnical Support Services is attached and is a part of this report The water samples were transported on ice by chain of custody to Sherwood Labs for analysis by EPA Methods 602 and 5030/8015(M) for BTEX, and TPHg FINDINGS FROM MONITORING WELL ANALYSIS The most important change for this reporting period is a+/- five feet raise in the ground water elevation The direction and slope of the hydraulic gradient have changed significantly The direction of flow is to the northeast at the time of this event The slope of the gradient is from S = 0 0015 (see attached site idrawing) The concentration of TPHg has increased in monitoring wells MW#1,MW#3,and MW#6S Monitoring well MW42, MW#7D, and MW#7S were analyzed at the same concentration level for TPHg as the last event All compounds of BTEX in MW#1 and MW#3 have doubled in value over the last event (See attached sample data recap sheets) The samples from the monitoring wells on the east side of Wilson Way continue to be non-detect For past events, analysis by EPA Method 8260 was reported as non- detect To conserve funds,water samples in the future will not be analyzed for EPA Method 8260,unless requested by the PHS-EHD CONCLUSIONS The +/- five feet increase in the groundwater table elevation from the 10/09/2000 event is a significant change in the site conditions This pattern of large variations in groundwater elevations may contribute to the change in contamination levels found in the last three sampling events There is a general downward trend in the levels of contamination in the groundwater from the first sampling event on 9/22/99 The hydraulic gradient has changed flow direction from the southeast of the last event to the northeast of this event RECOMMENDATIONS A review of groundwater receptors in the area of the site should be conducted to help determine the cause of the change in groundwater elevation and flow gradient direction Low concentrations of gasoline contamination are still present at one hundred feet of depth in MW#5D, MW#7D and MW48D Concentrations in these wells are falling at a steep rate of decline This may indicate that the contamination was transported down the bore hole with soil bonng operations and it may 2