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�} it Vertical and Horizontal Delineation of Plume History Monitoring Wells MW#1, MW#2, and NIW#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) Monitoring wells MW#8S and MW48D 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 A work plan for five CPT's and two monitoring wells has been approved and a preapproval request for funding by the UST Cleanup Fund as be submitted To this date, approval from the UST Fund has not be granted FOURTH QUARTER 2002 MONITORING WELL SAMPLE ANALYSIS REPORT Sampled 12/27/02 WATER ANALYSIS OF SAMPLES FROM MONITORING WELLS On December 27,2002, Del-Tech Geotechnical Support Services extracted water samples from each monitoring well using standard industry practices under the supervision ofFoothill Engineering A report of this work by Dei-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 SW 802OF for BTEX, and TPHg Samples of each set of groundwater extractions were forwarded to Entech Analytical Labs of Santa Clara, California for analysis by EPA Methods 8260FA The original chain of custody failed to request analysis for 1,2-DCA and EDB as ordered by this author After receiving the results for oxygenates without 1,2-DCA and EDB, a follow up request was made to Entech for those results The follow up results are on the recap sheet and a faxed copy of the lab result sheets are attached FINDINGS FROM GROUNDWATER SURFACE DETERMINATION The groundwater elevation on this site has raised about seven feet from the last sample event and is about two feet lower than in the fourth quarter of last year The slope of the groundwater gradient for this event is down slope to the northwest at S = 0 005 The last monitoring event had a hydraulic gradient with a slope to the west FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS FOR BTEX AND TPHg Samples from monitoring wells MW#4S,MW94D,MW#5D,MW#6D,MW#7S,andMW#7D continue to be analyzed at below detection limits for TPHg Monitoring wells MW#6S, MW#8S, and MW99D 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#513,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 2