SITE INFORMATION AND CORRESPONDENCE

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A WILSON, SONSINI,GOODRICH&;ROSATI Ms. Linda:Turkatte,-REHS May 26, 1993 Page requested that quarterly status reports be submitted to the Health Department and that the domestic wells on site-ire monitored quarterly for gasoline contamination. As discussed below, Color Spat submits that the vertical extent of the contamination has been defined and all contaminated soil removed, as indicated in the January 1990 rePorL Further, monitoring wells are not required at the site under applicable guidelines, and are technically infeasible to install DISCUSSIO Color Spot believer that it should not be required to conduct any further groundwater investigation at the site for the following reasons: 1., 'There is no evidence that Color Spot's tank caused the benzene contamination detected in the groundwater surrounding the site. There is absolutely no evidence that Color Spat's underground storage tank_caused the benzene contamination that has been detected in the groundwater near the site. First, the field observations from the tank removal indicate that the tank did not leak. SG&D reported that the tank appeared intact and structurally sound upon removal:. Neither SG&D nor the inspector;noted such defects in the tank as holes, rusting or pitting. Neither the inspector nor SG&D reported evidence of-a release such as the presence of free product in the excavation. In fact, all that those present noted was a;minor amount of soil contamination which subsequent field work confirmed was limited to the excavation. SG&D concluded that this contamination was likely the;result of overspill from filling;the tank. Therefore the tank was not leaking when removed. Second, subsequent soil and groundwater testing has confirmed that the benzene contamination in the off-site wells could not have possibly been caused by Color Spot's tank. The tank was used to store diesel fuel, which does not contain benzene. Test results taken from existing water wells on two separate occasions have indicated that benzene is present but that diesel is not. Finally, the groundwater at the site is over 90 feet below ground surface and there are stratum composed of clay material layer between the surface and the aquifer. A grab groundwater sample taken at 92 feet was non-detect for hydrocarbons. Therefore, the data clearly indicates that Color Spot's tank did not contaminate the groundwater. H:AHOME1 VMC\COLORS MTIJRM17.LTR(SP2)