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KEI-P8$-1013 .QR5 August 9 , 1993 Page 4 Approximately 11 hollow-stem auger borings, 14 hand auger borings, and two monitoring wells have been drilled at the Montgomery Ward site. TPH as gasoline was detected in soil samples collected from the borings for monitoring wells MW1 and MW2 at concentrations ranging from non-detectable to 6, 900 ppb and non-detectable to 3 , 110, 000 ppb, respectively. TPH as gasoline was also detected in an exploratory boring drilled within the former Montgomery Ward fuel tank area at a concentration of 2 , 270, 000 ppb at a depth of 50 feet below grade. The depth to ground water in wells MW1 and MW2 on March 5 , 1993 , was approximately 55 below grade. TPH as gasoline was detected in the water samples collected from wells MW1 and MW2 on March 4 , 1993 , at concentrations of 7 , 000 ppb and 24 , 200 ppb, respectively. Based on the information obtained from the May 27 , 1993 file review, and based on the analytical results of the recent ground water samples collected from the Montgomery Ward wells MW1 and MW2 (see Table 5) , it appears that a separate hydrocarbon release has occurred at the Montgomery Ward site. However, it is not known if contamination from the Montgomery Ward site has commingled with contamination from the Unocal site. Therefore, KEI recommends that additional monitoring wells be installed in the area between these sites. However, in order to coordinate these efforts, KEI recommends that a meeting be held between Unocal, Montgomery Ward, and their respective consultants to discuss further investigations at the respective sites. DISTRIBUTION A copy of this report should be sent to SJCPHS, and to the RWQCB, Central Valley Region. LIMITATIONS Environmental changes, either naturally-occurring or artificially- induced, may cause changes in ground water levels and flow paths, thereby changing the extent and concentration of any contaminants. Our studies assume that the field and laboratory data are reason- ably representative of the site as a whole, and assume that subsur- face conditions are reasonably conducive to interpolation and extrapolation. The results of this study are based on the data obtained from the field and laboratory analyses obtained from a state-certified laboratory. We have analyzed these data using what we believe to be currently applicable engineering techniques and principles in the Northern California region. We make no warranty, either expressed or implied, regarding the above, including laboratory