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h Vertical and Horizontal Delineation of Plume History Monitoring Wells MW#1, MW#2, and MW#3 were installed in September of 1999 to a depth of sixty feet Soil samples from the soil bores were extracted at five foot intervals from a depth often feet to sixty feet (see site map for location attached) All three soil bores produced samples above detection levels for BTEX and TPHg and TPHd(see Soil Sample Recap Attached) 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,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 MW#8D were installed in a single bore hole inside the existing building, west of the pump islands on October 3,2000 Monitoring wells MW#9S and MW#9D were constructed in a single soil bore on August 14, 2002 THIRD QUARTER 2002 MONITORING WELL SAMPLE ANALYSIS REPORT Sampled 09/10/02 WATER ANALYSIS OF SAMPLES FROM MONITORING WELLS On September 10, 2002, Del-Tech Geotechnical Support Services extracted water samples from each morutonng well using standard industry practices under the supervision ofFoodull 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 SW802OF . for BTEX, and TPHg Samples of each set of groundwater extractions were forwarded to Entech Analytical Labs of Santa Clara, Ca for analysis by EPA Methods 8260FA FINDINGS FROM GROUNDWATER SURFACE DETERMINATION The groundwater elevation on this site has dropped about 8 T from the measurements done on June 10, 2002 and is about 11 6'lower than in the first quarter of this year The slope of the groundwater gradient for this event is down slope to the west at S = 0 001 This is 180 degrees in the opposite direction compared to the slope of the groundwater gradient on February 13, 2002 1t should be noted that this is the first monitoring event that produced a groundwater gradient with a slope in the westerly direction since monitoring of this site began in fall of 1999 FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS FOR BTEX AND TPHg Samples from monitoring wells MW#4S,MW#4D,MW#5D,MW#6S,MW#6D,MW#7S,and MW#7D continue to be analyzed at below detection limits for TPHg Monitoring wells MW#2, MW#8D, and MW#8S are the only monitoring wells that analyzed higher than the last event for TPHg FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS FOR OXYGENATES The presence of 1,2-DCA was detected in samples extracted from MW#1,MW#2, MW#5D,MW#7D, MW#8S&8D,and MW#9S&9D The highest concentration of 1,2-DCA was found in monitoring well MW#1 which is located in the dispenser island area, and in MW#8D which is directly west ofMW#1 CONCLUSIONS The water table elevations on this site continue to fluctuate Concentrations of TPHg have continued 2