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1 � • <br /> LEEDSHILL•HERKENNOFF, INC. <br /> 3. LVMD#6 has probably been impacted in a similar way to LVMD #1 . <br /> Discussions with representatives of SJCPW indicate that during the <br /> summer of 1984, LVMD #6 was "reworked" to correct a problem with <br /> the well producing large quantities of very fine sand. The prob- <br /> lem was corrected with the installation of a PVC liner and sand <br /> pack within the original well . The well was originally <br /> constructed over 30 years ago and is reported to have only a <br /> 40-foot sanitary surface seal . It is not inconceivable that water <br /> from the contaminated upper water bearing zone (which is <br /> ' approximately 45 feet below the ground surface) could have entered <br /> the well through a hole or casing fracture, either before or <br /> during the 1984 well rework. Subsequent to the rework, if the <br /> ' installed sand pack around the PVC liner was not sealed off in the <br /> upper zone, the very permeable sand pack could have acted as a <br /> vertical conduit. However, as discussed in Section 4.1, currently <br /> the groundwater gradient in the upper aquifer is eastward away <br /> from LVMD #6, and, in the deeper aquifer, it is toward the cone of <br /> ' depression created by LVMD wells #1 and #2. The aforementioned <br /> theory is based on limited data since LVMD #6 has not not been <br /> pumped or sampled since December of 1986 and no recent water <br /> ' quality data is available. Also, LVMD #6 can not be video <br /> inspected due to the configurations of the sand filter. <br /> ' The soil samples collected beneath each of the dry cleaning establishments <br /> indicated the presence of detectable concentrations of PCE. PCE and/or TCE <br /> ' were also detected in sewage samples from sewer lines serving these <br /> facilities. <br /> ' Although PCE and/or TICE is still being found in the sewer, it is unlikely <br /> that either of the sewers near LVMD #1 are continuing sources of groundwater <br /> contamination. First, all joints within a one-hundred foot radius of LVMD <br /> ' #1 have been inspected and sealed. Also, soil samples collected beneath the <br /> sealed sewer lines were dry, indicating that water leakage had stopped. <br /> 5-4 <br />