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industry practices under the supervision of Foothill Engineering A report of this work by Del-Tech • Geotechnical Support Services is attached and is apart of this report The water samples were transported under ice by chain of custody to Sherwood Labs for analysis by EPA Methods 602, 5030/8015(M) for BTEX, TPHg and TPHd A water sample from each monitoring well was transported from Sherwood Labs under chain of custody to Entech Analytical Labs, Inc for analysis by EPA Method 8260B FINDINGS FROM MONITORING WELL ANALYSIS The most important change for this reporting period is the nse of 3 8 feet in the ground water elevation The direction and slope of the hydraulic gradient have also changed The direction of flow has moved from the northeast to the east The slope of the gradient has changed from S = 0 004 to S = 0 002 (see attached site drawing) The concentration of TPHg has increased in both MW#1 and MW#3 Monitoring well MW#2 has had a small reduction in TPHg from the last sampling event There has been a very small increase in benzene for monitoring wells MW#1 and MW#3 (see attached sample data recap sheet) Benzene in MW42 has decreased from the last sampling event All analysis for oxygenates were non-detect for each monitoring well CONCLUSIONS The 3 8 feet rise in the groundwater table elevation is a significant change in the site conditions This raise in the water table may be a result of the heavy rainfall in the month of February All monitoring wells now have a groundwater table above the top of screen elevation . After three quarters of sample analysis for oxygenates, all water samples have been non-detect 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 direction There is no indication that oxygenates are present in the groundwater on this site To conserve financial resources, analysis for oxygenates will not be continued without a request of the PHS-EHD The author recommends that three new monitoring wells be installed to determine the extent of the contamination plume MW#4 is to be installed in the sidewalk of the eastside of Wilson Way due East of the site at first groundwater A deep monitoring well, MW45, is to be installed at the same location and will extend to bottom of the contamination plume A third well, MW#6, should be placed near the center of the fuel dispensing islands with the screen section placed at the bottom of the plume Respectfully submitted, �?,GKSs!p,, �C4 Ov�M RI FlNBv`�� Footh ee —00 �c cap tv 1975 Ervin Ri nb PE . . QFCAI'� Attachments Water Analysis, De - ech Report, Site Map cc Sheldon Heckman, Connell Motor Truck Co 2 copies 2