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split spoon sampler on five foot intervals,starting at a depth of ten feet and proceeding to a depth of sixty feet Each sample was logged and classified by the unified soil classification system Selected samples were capped,sealed,and placed on ice for delivery under chain of custody to Sherwood Labs Spoil from the boring operation was collected in 55 gallon drums for disposal at a certified disposal site MONITORING WELL INSTALLATION Three two-inch PVC monitoring well casings were installed at a depth of 60 feet as per the attached drawing The installation of the monitoring well under the dispenser canopy was very time consuming as vertical clearance did not allow for the drilling ng to extend the drill boom The other two monitoring wells were constructed using typical methods All monitoring wells were developed and purged by Del- Tech Geotechnical Support Services using methods standard to the industry Development and purge water was stored in plastic drums for future disposal SOIL ANALYSIS OF SAMPLES All samples from the soil borings were transported under chain of Custody for analysis by EPA methods for BTEX , TPHg and TPHd One selected sample from each soil bore was forwarded under chain of custody to Entech Analytical Labs, Inc for analysis by EPA method 8260 A recap of all soil analysis is attached to and a part of this report WATER ANALYSIS OF SAMPLES FROM MONITORING WELLS Del-Tech Geotechnical Support Services extracted water samples from each monitoring well by standard industry practices under the supervision of Foothill Engineering A report of these activities by Del-Tech Geotechnical Support Services is attached and apart of this report Water samples were transported under ice by chain of custody to Sherwood Labs for analysis by EPA methods 602, 5030/8015(M) and 3510/8015(M)for BTEX,TPHg,and TPHd A water sample from each monitoring well was transported • under chain of custody to Entech Analytical Labs, Inc for analysis by EPA method 8260B FINDINGS Soil samples M W#1 @25'&MW#1 @30'were the only samples found to contain TPHd All soil samples were found to be non-detect for all oxygenates The highest concentration of targeted hydrocarbons is in the samples extracted from a depth of 55 and 60 feet that are about ten feet below the groundwater Xylene is the BTEX compound found in the highest concentrations in soil samples All water samples were analyzed as non-detect for all oxygenates BTEX compounds in the groundwater were found in the highest concentrations in MW#1 The concentrations of TPHg in monitoring wells MW#2 and MW#3 were about one half the concentrations ofMW#1 The groundwater gradient is down slope to the Northeast at S=0 0007 CONCLUSIONS It is evident from the soil and water samples that center of the plume and the highest concentrations of contaminates is closer to MW#1^than the other two monitoring wells The water samples from MW#2 acid MW#3 contain lower concentrations of Benzene than MW#1 This indicates a natural break down and dilution of the of BTEX compounds found in MW#1 which is up gradient from MW#2 and MW#3 (see site map for flow direction) Soil borings for MW#2 and MW#3 show only contamination below groundwater This may indicate that the spread of contamination is by the groundwater and not by gravity in the soil matrix The most likely source of the contamination is in the area of the westerly dispenser island that is nearest to monitoring well MW#1 The spill could have come from product piping or a dispenser 2