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t- Monitoring Wells MW#4S and MW44D were installed on the east side of Wilson Way in September of • 2000 Also,monitoring wells MW#5D,MW#6S 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) Monitonng wells MW#8S and MW8D were installed in a single bore hole inside the existing building,west of the pump islands on October 3, 2000 THIRD QUARTER 2001 MONITORING WELL SAMPLE ANALYSIS REPORT Sampled 9/13/2001 WATER ANALYSIS OF SAMPLES FROM MONITORYNG WELLS On September 13, 2001, Del-Tech Geotechnical Support Services extracted water samples from each monitoring well using standard 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 Method S W8020 for BTEX, and TPHg FINDINGS FROM GROUNDWATER SURFACE DETERMINATION The groundwater elevation on this site has dropped about 11 5'from the sampling done on March 16,2001 and T from June 19,2001 The groundwater elevation is about 5'below the third quarter measurement of last year The slope of the groundwater gradient for this event is to the northeast at S = 0 001 FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS The concentration of TPHg in monitoring wells MW#2, MW#3 are lower than last quarter MW#1 has a higher concentration of TPHg than it had in the second quarter Monitoring wells MW#8S and MW#8D remain in the same range as last quarter MW#7D,MW#7S,and MW#6Dare non-detect for all analyzed compounds this quarter The monitoring wells(M W#4S&MW#4D)on the eastside of Wilson Way have returned to non-detect status for all analyzed compounds (See attached sample data recap sheets) CONCLUSIONS The continued non-detect status of TPHg in the monitoring wells MW#7S and MW#6S may be a result of lower elevation of the groundwater The plume has changed direction of flow and both the shallow and deep wells(MW#4S&MW#4D)on the eastside of Wilson Way have returned to non-detect status from detect status of last quarter The four monitoring wells near the center of the spill have remained in the same range of concentrations for each analyte as the second quarter samples Monitoring wells MW#8S and MW#8D, directly west of the spill area, have remained in the same range as last quarter 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 • The groundwater sample results gathered by the last four groundwater sample events indicate that both the vertical depth and horizontal limits of the contamination have been reached and further investigation below 2