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I 5 0 CONCLUSIONS Groundwater elevations recorded during the Third Quarter 2005 sampling event (excluding well MW-5D) were on average 0 85 feet lower than the elevations measured during the Second Quarter 2005 The lowering in groundwater elevation is typical to historical data for this time of year During the Third Quarter 2005, three of the five wells with a detectable concentration of MTBE had IMTBE concentrations in groundwater less than the MCL of 13 ug/1 In the previous quarter, no well exceeded the MCL for MTBE In Third Quarter 2005, benzene concentrations in wells MW-3 I (200 ug/l) and MW-7 (80 ug/l)exceeded the MCL of l ug/l ' Prior to the implementation of remedial actions at the Site, the estimated soil contaminant mass was calculated to be 25,264 pounds of gasoline within the vadose zone and capillary fringe The mass removal calculations for the SVE system indicate that through July 12, 2005, the SVE system has Iremoved approximately 18,325 pounds of TPHg (72% of the original estimated mass) from the soil The SVE system removed contaminant mass from the soil at an average rate estimated of 3 5 pounds per day during this reporting period In December 2004, the ozone sparge system became non-operational due to system component I . failures In January 2005, parts from a similar system were scavenged to return the ozone sparge system at the Site back to service By April 2005, several mechanical failures had again rendered the I ozone sparge system non-operable The manufacturer of the sparge system is now defunct and replacement parts are not available The ozone sparge system will remain offline indefinitely I I I I i Project No S8643-06-01 -1 1- September 28 2005