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The vertical distribution of VOCs in groundwater within the LNC site vicinity is not as well defined because of the length of time between the discrete-depth HydroPunch samples collected in 1993 and 1994, soil gas samples collected in 1996, the multi-depth discrete groundwater samples collected during the City-wide sample event in 2000, and ongoing City of Lodi groundwater monitoring well sampling since 2000. When these data are plotted in cross-section (Figure 6), VOCs may be interpreted to be present in groundwater to a depth of at least 90 feet bgs in HPT05 under the LNC site, down to a depth of at least 115 feet bgs at HPT06, and 121 feet bgs at HPTO1 further downgradient(Figure 6). Shallow groundwater also is impacted south of HPTO1 at soil boring C-37. Vertical profiling in City well CW#4 indicates the presence of VOCs in groundwater produced from water bearing zones located from 80 to 200 feet bgs (Figure 5) (Henshaw, 2001). Itis very likely that the presence of VOCs at significant depth beneath the LNC site and areas south of it is the result of continued pumping of City Water Supply Well CW#4. Downgradient of CW#4, the discrete-depth HydroPunch results from HPB02 and HPB03 indicate only the presence of PCE in shallow groundwater. VOCs were reportedly not present at a depth of about 90 feet from these sample points. This is consistent with the hypothesis that a source of PCE exists in this vicinity of the HPB borings (Busy Bee Site) and that VOCs entrained in groundwater producing zones upgradient of City well CW #4 may have been captured by pumping from City well CW #4. 4.6 Monitoring Well Sampling During the City-wide investigation conducted by the City of Lodi in 2000, twenty groundwater monitoring wells were installed and sampled. Of these, five monitoring wells were installed within the northern portion of the City of Lodi, including one well (MW-01) located immediately upgradient of the LNC site and one well (MW-02) located approximately 1,000 feet downgradient of the LNC site (Figure 5). No monitoring wells have been installed to date on the LNC facility. M ain\D:AEnvironmentaI\LN CV\10152007.wpd 21