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monitoring well by 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 GeoAnalytical for analysis by EPA Methods 8260B, 8021B 5030/8015(M) for BTEX, TPHg, and oxygenate FINDINGS FROM MONITORING WELL ANALYSIS The most important change for this reporting period is a+1-2 5 feet drop in the ground water elevation The direction and slope of the hydraulic gradient have not changed significantly The direction of flow is to the southeast The slope of the gradient is from S = 0 001 (see attached site drawing) The concentration of TPHg has decreased in all monitoring wells by a minimum of 50 percent Monitoring well MW#3 has the largest reduction of nearly 500%in TPHg from the last sampling event All compounds of BTEX have been reduced Concentrations of TPHd were found in MW#2 and MW#1 (see attached sample data recap sheets) All analysis for oxygenates were non-detect for each of the monitoring wells CONCLUSIONS The 2 5 feet drop in the groundwater table elevation is a significant change in the site conditions This drop in the water table may be a result of the irrigation pumping in the area After four 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 Respectfully submitted, ,z �ffS3;p , Foothill Ery nee �t rV;`� Ervin Ri�e u E Exp 13FGl;U�.ti�`• Attachments Water Analysis Recap, Del-Tech Report, Site Map cc Sheldon Heckman, Connell Motor Truck Co 2 copies 2