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�CAMBRIA <br /> No total petroleum hydrocarbons as gasoline (TPHg), benzene, or methyl tertiary butyl ether <br /> (MTBE) were detected (by EPA Method 8260B) in any of the wells this quarter Methanol <br /> and ethanol were detected in all three wells at concentrations ranging from 140 to 230 parts <br /> per billion (ppb) and from 7 4 to 12 ppb, respectively No other fuel oxygenates, <br /> 1,2-dichloroethane (1,2-DCA), or 1,2-dibromoethane (EDB) were detected in groundwater <br /> beneath the site <br /> Ethanol detections are common in groundwater from recently installed wells that were <br /> constructed with bentonite pellets, as these wells were If the ethanol originated from the <br /> bentonite seal, we would expect the concentrations to decrease over time Methanol is a <br /> common laboratory contaminant, and in this case, the laboratory suspects that it may have <br /> originated from the sample container preservative <br /> ANTICIPATED SECOND QUARTER 2001 ACTIVITIES <br /> Cambria has received written approval of our March 28, 2001 revised work plan from <br /> SJCPHS/EHD and we will implement the proposed field work The field work is scheduled for <br /> April 11, 12, 13, and April 16, 2001 Upon receiving the results of this investigation, <br /> Cambria will prepare a report of findings <br /> Blame will coordinate the sampling event with the former Chevron station located at <br /> 301 West Kettleman Lane according to the existing sampling schedule, gauge and sample the <br /> wells, and tabulate the data Cambria will prepare a groundwater monitoring report <br /> RECOMMENDATIONS <br /> Cambria recommends double-purging all monitoring wells prior to sampling We will also <br /> request that Blaine obtain the hydrochloric acid-preserved water sample vials from the <br /> laboratory to ensure that there is no methanol present in the preservative We recommend <br /> analyzing samples from all three wells, an equipment blank, and a trip blank for TPHg, <br /> benzene, toluene, ethylbenzene, xylenes, MTBE, methanol, and ethanol by EPA Method <br /> 8260B Because they were not detected, Cambria recommends discontinuing analyses for <br /> ethyl tertiary butyl ether, tertiary butanol, dt-isopropyl ether, tertiary amyl methyl ether, <br /> 1,2-DCA, and EDB We will implement these changes to the quarterly protocol beginning <br /> with the second quarter 2001 sampling event unless otherwise directed by the SJCPHS/EHD <br /> or RWQCB <br /> 1346 2 <br />