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r Extended Plume Definition:-7500 W 111h St..Tracy.CA. page 19 month, less than one ounce of LNAPL was recovered from the well when it was again purged on December 21, 2003, and,when it was purged on March 30, 2004, there was only a trace or sheen of LNAPL detected in that well.. The thicknesses of LNAPL that have been measured in Monitoring Well MW-7 since 2002 are recorded in Table 5. As is described above, initially, floating product from Monitoring Well MW-7 was purged on a weekly basis. However, since a significant thickness of floating product failed to reappear in the well seven days after the November 15th purging, SJC reduced the purging frequency to once per month and, on December 21, 2003, to a quarterly frequency to achieve a cost- effective operation. On March 30, 2004, the next quarterly purging was conducted. At the time of the latter two purgings, no more than a trace of LNAPL was detected in MW-7. Accordingly, specific LNAPL purging operations at MW-7 have been discontinued. However, that well continues to be purged of any floating product present as part of the routine quarterly water-quality monitoring procedures currently scheduled at the Navarra Site. 5.3 Extended Investigation of LNAPL in Subsurface In response to a request made by SJCEHD staff, the extended site characterization conducted at the Navarra Site in April 2004 included installation of monitoring wells to investigate the extent of floating product that may be present on the groundwater in the parking lot north of groundwater-quality monitoring wells MW-6 and MW-7. For that purpose, on April 19-22, 2004, SJC installed five 2-in diameter, 15-ft. deep floating product monitoring wells at the locations shown on Figure 2. Designated MWFP-1 through MWFP-5, they were designed to be used in conjunction with the pre-existing Monitoring Well MW-7 and newly-installed groundwater-quality monitoring wells MW-13 and MW-14. The procedures used for installation of, soil sampling and drill-cutting disposal from, well development and measurement of depth to groundwater in, and surveying of the floating product monitoring wells were similar to those used for the groundwater-quality monitoring wells, as described in Section 4.0. The well construction details of the floating product monitoring wells are shown on their well logs, copies of which are included in Appendix A. Analyses of the soil samples recovered from those well borings are included in Table 2. Although the new groundwater-quality monitoring wells MW-13 and MW-14 were primarily designed to investigate groundwater quality along the down-gradient axis of the plume of affected groundwater emanating from the 7500 West Eleventh Street property, to permit their possible use as LNAPL recovery wells should such operations be required in the future, they were installed with 6-in diameter casings. As part of the round of groundwater quality monitoring on April 30, 2004 (see Section 4.10 above), the depths to groundwater in floating product monitoring wells MWFP-1 through MWFP-5 were measured and those measurements were incorporated into the data array used to construct the groundwater contours shown on Figure 9. However, those floating product monitoring wells were not purged or sampled during that monitoring round. In order to determine whether LNAPL will appear in water in a well where the water table is located at sic