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Quik Stop No 121 Closure Report CCI Project No 12118 Page 9 concentration maps for TPHg and MTBE from January 2002, April, 2002, July 2002, October 2002 and April 18, 2006 are provided in Appendix D Laboratory data collected during the January 2000 quarterly sample round indicated monitoring well MW-3 to have significantly higher concentrations of TPHg and MTBE CCI resampled the well in February to confirm the high concentrations of MTBE CCI proposed pumping the well on an interim bases to lower the concentrations of MTBE On March 30, 2000, approximately 1,300 gallons of water was pumped from MW-3 in an attempt to lower the MTBE concentration This process was repeated in September 2000, when approximately 400 gallons of water were pumped from the well It should be noted the water table was relatively low and the well dewatered during pumping The extracted groundwater was transported by Industrial Waste Utilization, Inc to Seaport Environmental, located in Redwood City, California for proper disposal In February 2001, CCI continued interim remediation of the groundwater in the vicinity of MW- 3 and RW-1 by using TRC's Mobile Treatment System (MTS) The MTS consisted of a mobile dual phase vapor extraction and groundwater treatment system The purpose of using the system was to determine whether dual phase vapor extraction was a viable remediation option for the site and to further help reduce the MTBE groundwater contamination in the vicinity of MW-3 and RW-1 From February 2001 to December 2001, a series of 8-hour dual-phase treatment events were conducted at the site The vapor extraction events were conducted mainly on wells MW-3 and RW-1 A total of 9 MTS events were conducted at the site During that time, a total of 47 29 gallons of equivalent product were removed from the site In addition, a total of 4,854 gallons of water were extracted from wells MW-3 and RW-1 Due to decreasing equivalent product removal rates, which dropped from over 9 gallons per event in the beginning to 2 gallons or less after event number 9, Quik Stop decided to terminate the monthly MTS events and work toward installing a permanent remediation system A summary of the MTS events are included in Tab2, Table 5 Copies of the MTS reports are attached in Appendix E 5. REVIEW OF REMEDIAL METHODS As indicated earlier, in January 2002, CCI reviewed several potential remediation methods for use at the site They included pumping and treating the groundwater with granulated activated carbon(GAC), dual-phase vapor extraction, with the extracted groundwater being treated with GAC, and treating the groundwater contamination in-situ using an ozone infection technology Ozone is a highly reactive chemical that is very effective in destroying a wide variety of organic compounds, including methyl tertiary butyl ether (MTBE) In general, this technique uses several porous plastic sparge points (wells) which are connected to an ozone generator Ozone is Sintroduced into the aquifer in the form of micro-fine air bubbles under low pressure in order to