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C A M B R I A <br /> June 2000 the GWE occurred weekly During each GWE event, approximately 5,000 gallons <br /> of water is purged by a vacuum truck and transported to the Martinez Refining Company for <br /> recycling On August 22, 2000 a pump was installed in RW-lA and it currently pumps into a <br /> Baker tank A vacuum truck then empties this tank as previously described above As of <br /> November 28, 2000, approximately 332,725 gallons of water have been removed from <br /> RW-1A As shown on Table 2, based on the concentration data, groundwater extraction has <br /> effectively removed approximately 285 5 pounds of TPHg, 31 7 pounds of benzene, and <br /> 427 9 pounds of MTBE <br /> ANTICIPATED FOURTH QUARTER 2000 ACTIVITIES <br /> Blaine will gauge and sample the site wells according to the existing sampling schedule and will <br /> tabulate the data Cambria will prepare a groundwater monitoring report <br /> CONCLUSIONS AND RECOMMENDATIONS <br /> The petroleum hydrocarbon and MTBE concentrations in groundwater samples collected <br /> from the shallow wells this quarter are within the historical norm for this site Wells MW-5, <br /> MW-8, and RW-lA continue to contain the highest levels of hydrocarbons and MTBE <br /> However, analytical data from offsite wells suggests the hydrocarbons and MTBE detected <br /> onsite wells (MW-5, MW-8, and RW-1A) are remaining onsite <br /> Groundwater samples from the Foster well contained 6 94 ppb MTBE by EPA Method 8020 <br /> This is the second confirmed detection of MTBE in this well This well is currently out of <br /> service and the Foster residence is hooked up to the city water supply TPHg was not <br /> detected in the Sanella well this quarter The Sanella residence is also hooked up to the city <br /> water supply and the well is only used for irrigation purposes Since none of the other wells <br /> located between the Foster well and the Shell Service Station contain detectable levels of <br /> gasoline constituents, it is unlikely the gasoline constituents detected in this well originated <br /> from the Shell Service Station Another fact that supports this is that groundwater flow <br /> direction at the Shell site is typically toward the northeast The Foster well is located more <br /> than 1,000 feet south-southeast of the Shell site <br /> Groundwater samples from the CalTrans irrigation well and the other private water wells did <br /> not contain TPHg, benzene, or fuel oxygenates this quarter We will continue quarterly <br /> groundwater sampling and analysis to confirm the presence or absence of MTBE in these <br /> wells <br /> 0783 2 <br />