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I near the south end of the 12000-gallon diesel tank. Installation of MW-1 Monitoring well MW-1 was installed on 5/14/2001 to a depth of 55 feet in a soil bore that was sampled on five foot intervals (See Log of Boring MW-1 attached). Groundwater analysis for the samples produced by this monitoring well are attached. REPORT OF FINDINGS FROM THE MW#1 (aka UST-1) Second Half Sampling Event Sampled 12/29/03 Water Sampling and Analysis Water samples from MW#1 were extracted by Del-Tech Geotechnical Support Services on 12129103. The samples were transported under chain of custody to Sherwood Labs.Pump purge rates were one G.P.M. Depth to the water surface was 51.67 Nvith a+/-4'stickup on the casing. The water table at the time of sampling was about 47' below the surface. TPHd and BTEX were analyzed by EPA Methods EPA 8015(M) and EPA 8020 by BSK Laboratories. Findings from Sample Analysis Analysis by all of the above methods resulted in non-detect status for each of the analytes analyzed. Conclusions from this Groundwater Sample Analysis The laboratory results for this sample period are non-detect. The previous results of 05124101, 10122101, 06113102, and 06/09/03 of water samples extracted from this monitoring well were also • non-detect. The analysis of the groundwater samples from the 3/01/2002 were rejected due to the fear of contaminated samples in the laboratory (Note underlined sample data in Water Sample Analysis Recap attached). The groundwater elevation has lowered about two feet. Five out of a total of six groundwater samples from monitoring well MW-1 have been analyzed as non-detect for all analytes. The only sample to indicate the presence of BTEX was sampled on 03101102. TPHd was found to be non-detect on that sample. The author concludes that this sample was contaminated in the extraction process or in analysis by the laboratory.It is safe to conclude that the spill from the UST did not reach the groundwater.An impervious strata between 35'and 45'will prevent any further downward movement of the spill plume(See soil bore lithology attached). Soil samples taken during the soil bore for MW-1 were analyzed as non-detect from a depth of 30' to termination. Estimated Diesel Mass Calculation The diesel mass of this spill is calculated at 1128 Kg. This mass was calculated using the soil analysis of samples extracted from the MW-1 soil bore. The center of the radius was determined from the UST excavation wall stains. The radius of the spill had to be assumed as there is only one soil bore on this site.A 45 degree lateral dispersion angle of the plume was used in this calculation. This estimated dispersion angle may actually be more or less from the angle used in this calculation. Natural Bioremediation of the Unsaturated Zone From samples taken for the RWQCB, it was determined that the water in MW#1 contains +/- 22 . ug/L of Nitrate (NO3). Nitrate is an electron acceptor for the bio-reaction of hydrocarbons. if any hydrocarbons were present in the unsaturated zone or the groundwater, they would soon be remediated by a very active bioreaction due to the presence of a nitrate electron acceptor. 2