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Ghevron U.S.A. <br /> Wage 28 <br /> ^' Table V presents a composite summary of all test results of the original <br /> monitoring wells prior to their going dry and the construction of the new wells MW-2A, <br /> MW-4A, MW-5A, MW-8, MW-9, MW-10, and MW-11. The original test results, starting in <br /> October, 1986 when monitoring wells MW-1, MW-2 and MW-3 were constructed, revealed MW- <br /> 2 to have a moderate petroleum contamination. The contamination in MW-2 diminished <br /> and then began to increase to much higher reported contamination by mid-1989. This <br /> represents a several month interval when there was little or no contamination in well <br /> ! MW-2. There is no known up-gradient source of contamination and itis very unlikely <br /> �.x that contaminants within the soil took several months to migrate to the groundwater. <br /> l These facts,in addition to the relatively clean test results found in monitoring well <br /> wn gradient of monitoring well MW-2 further <br /> MW-2A approximately five feet north and do <br /> leads to the suspicion of monitoring well MW-2'S lack of integrity. The observed <br /> condition of monitoring well MW-2 and the apparent contamination from surface sources, <br /> present facts such that the quarterly monitoring results during 1988 and 1989 of <br /> F monitoring well MW-2 may have been as a result of the surface contamination entering <br /> the poorly,pealed well. <br /> The remaining wells down gradient of monitoring well MW-2, specifically MW-6 and <br /> MW-7,had shower only slight,increases in petroleum contamination from mid-1988 through <br /> ., <br /> mid-1989,when the wells went dry. Their moderate increase could have been expected <br /> being down gradient and the time lapse since the first suspicioned release in 1984. <br /> ,y 16000-205-O44 <br />