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i ito groundwater in each monitoring well was measured to the nearest 0 01 foot with a Solinst water level meter As in previous momtonng events, no groundwater was present in MW-1 After measurement of the depths to water, a 4-inch Grundfos submersible pump was used to surge and purge the wells Between 52 and 76 gallons of water (minimum of 3 well volumes) were removed from each well to stabilize temperature, pH and conductivity before i collection of a water sample Stabilization data were collected using Onon pH, conductivity and temperature meters The purge water was placed in 55-gallon drums and stored on-site Stabilization data are included in Appendix A iA water sample was collected from each well using a new disposable plastic bailer Each sample was collected in five 40-m1 EPA vials, placed in a chilled container and transported ito a state-certified laboratory 3.3 Laboratory Analysis i water samples were transported to Alpha Analytical Laboratories (AAL) in The soil and p p P yt Ukiah and for analysis Six soil samples were analyzed for TPH as gasoline and volatile iaromatic compounds (BTE&X) in accordance with EPA methods 8015 and 8020, respectively Three of the samples were also analyzed for halogenated organic compounds (HVOC's) in accordance with EPA method 8010 i The water samples were analyzed for TPH as gasoline. BTE&X and HVOC's in accordance with EPA methods 8015, 602 and 601, respectively i4.0 FINDINGS 4.1 Hydrocarbon Impacted Soil iTPH as gasoline, benzene and ethylbenzene were detected in sample VW1-25 at 14,000µglg (ppm), 14 ppm and 220 ppm, respectively Toluene was detected in VWI-25 and VW1-45 i at concentrations of 600 ppm and 0 0064 ppm, respectively, xylenes were detected in VW1- 25, VW1-35 and VW-45 at concentrations of 1,200 ppm, 0 018 ppm and 0 0058 ppm, respectively No HVOC's were detected in the soil samples The analytical results of the soil isamples are summanzed in Table 1 The laboratory report and chain of custody are included in Appendix C i4.2 Groundwater Gradient and Direction At the time of monitoring, groundwater depth at the site was approximately 79 feet The idepth to groundwater has risen approximately 3 feet since the January monitonng This is consistent with a regional rise in groundwater depth since January Well casing elevations iand groundwater depth data are summarized in Table 2 C 1nyal A.61 S.ry 1., Af-dl P-P-n—QM 9411 33 I