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t Each of these concerns are addressed individually below: 1 . The RWQCB disagrees with the conclusion that the areal extent of aquifer contamination is limited to the area around MW3, on the grounds that three of the wells con- tain insufficient water to obtain valid water quality samples. g - Although future verification of the absence of contamination in the wells does depend upon the presence of water in the wells, a the past record of sampling documents generally decreasing con- taminant concentrations in the wells. A review of the results of analysis of the. ten groundwater sam- pling events that,have been conducted at the site since November y 1986 show that contaminant: concentrations in the wells have gen- ' k eraliv decreased with time (Table 1 ) . Water irORO contained dete-ctable BTEX and .TPH when sampled in 1986 and 1987, but it has not contained benzene or TPH .in.detect- able concentrations since at least February 1988, a period of .two f . years Since that time, .toluene has been detected in waterfrom this well' :on`two occasions, both times at levels of less than 2 ug/L;`: close to. the`detection limit. of 0.5 ug/L. No ether petro N" leum contaminants were present in detectable concentrations at t " those times, (Table .1 ). Water froPnalso has; not contained detectable benzene or TPHin the eialyses campleted since February "1988. Over this two-year period, the cinly hydrocarbon component detected in water from this well was 0:'.6 .ug/L toluene' (detection limit 0.5 ug/L) . in asample collected il-i January 1989 `(Table 1 ) Water.. from MW3 has f;hown a general decline in hydrocarbon con- tamination levels on- tamination .levels since the well -was installed in 1986. The .most recent sampling. indicates that water in this well still contains. ti e35/71050/2-90/tx 5