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MONITORING WELL SAMPLE EVENT OF 9/18/2001 Sampling Procedure P g Monitoring wells were vented and purged by normal methods per standards of the industry(see Groundwater Field Report by Del-Tech Geotechnical Services attached). Purge rates are unknown,as a bailer was used. Groundwater samples were extracted from each monitoring well using the standard bailer technique.Samples were transported on ice for delivery under chain ofcustody to GeoAanalytical Laboratories for analysis.Only monitoring well GMX-1 and MW-3 produces enough water to extract a sample.Mw-2 and MW-4 were to low to produce a sample and are considered to be dry. Sample Analysis Water samples were analyzed by EPA methods 8021B for BTEX, 5030/Luft for TPHg, and EPA 8260B for Oxygenates.Results of all sample analyses are attached in the original laboratory form and in recap form. Findings From Water Sample Analysis The samples from monitoring well MW-3 and GMX-1 both produced a detectable amount of Oxygenates present. BTEX and TPHg levels remain within the same range for GMX-1 as the last event.Monitoring well MW-3 was non-detect for TPHg as were the results of the last event. The groundwater surface has lowered about+1-T from the last event(see Del-Tech Field Report enclosed). The groundwater hydraulic gradient has changed direction from south to southeast at a slope of S=0.003. Conclusions • A major lowering of MTBE levels occurred last quarter with lower groundwater table elevations and the trend continues with similar values for is event. The water sample analysis from monitoring well GMX-1 continues to produce low levels of TPHg.The more soluble Oxygenate compounds may be reaching higher dilution levels with the drop in groundwater elevation.The less soluble TPHg compounds have remained at the same concentration levels for the last three Quarters. Recommendations As in the last event report,it is recommended that the installation of a groundwater reclamation system begin before the finish ofthe current property development.As of the date of this report,preapproval for the first step in a reclamation system has been received and the extraction well has been installed.The aquifer pump test should be completed by the end of the month. Quarterly groundwater monitoring should continue. Please contact Ervin Rifenburg of this office(2091368-93 81)if any questions arise concerning this Report. Respectfully submitted, Foothill Engineering Ervin Rifenburg, RCE . cc: Diana Maragos, Attorney for Sun West Liquors cc: W. T. Mitchell Group 2