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Closure Documentation—7500 SMEleventh Street, Tracy, CA, Page 15 The San Joaquin Company Inc. (2003a), Work Plan for Refined Plume Definition and Management of Floating Product at Former Fueling Station, 7500 West Eleventh Street, Tracy, California. December 2003. The San Joaquin Company Inc. (2007), Corrective Action Plan for Former Fueling Station, 7500 West Eleventh Street, Tracy, California. July 2007. The San Joaquin Company Inc. (2007), Corrective Action Plan Addendum) for Former Fueling Station, 7500 West Eleventh Street, Tracy, California. October 2007 The recommended remediation technology had been applied to areas on the 7500 W. 11th Street property where soil was affected by high concentration of contaminants and where LNAPL was found floating on the groundwater table in December 1998. Highly contaminated soil was excavated from beneath the service station pump island and disposed off-site at a permitted facility. Some 2000 gallons of LNAPL and highly contaminated groundwater was suctioned from the quiescent surface of the groundwater after it had flowed from beneath the pump island into the large pit from which underground storage tanks had been exhumed. That action cost-effectively removed all LNAPL from the subsurface beneath the 7500 W. 11 th Street property to a distance northward under West 11th Street of some 125 ft. down gradient from the location where the fuels were released. Thereafter, vigorous aerobic natural attenuation of contaminant concentrations in groundwater was initiated, as measured in samples of groundwater recovered from Monitoring Well MW-3 (see Figure 3 for location), which was installed adjacent to the point of release of the petroleum hydrocarbons. Despite the clearly evident success of the selected remediation technology in improving groundwater quality beneath the 7500 W. 11th Street property, the SJCEHD's then- Certified Unified Program Agency Program Coordinator, who was not licensed to practice civil or geotechnical engineering or geology in any state, would not permit the BAT to be used to remediate LNAPL and highly-contaminated groundwater in the area around Monitoring Well MW-7 on the north side of W. 11th Street and provided no scientific or engineering reason forher decision. Lacking regulatory authorization to apply the best available technology in that area, active remediation of groundwater in the area around Monitoring Well MW-7 was limited to intermittent extraction of LNAPL from that well into a 50-gallon drum using a small diameter hose attached to a Weldon pump. Due to employment of this marginally effective and Iaborious procedure, aerobic bioremediation of the groundwater in the area around Monitoring Well MW-7 did not initiate until February 2008 and it was not fully freed of LNAPL until February 2010. This delay can be compared to the rapid onset of aerobic bioremediation and rapid decline in contaminant concentrations in groundwater in the area around Monitoring Well MW-3, where the hydrocarbons had been released and the BAT remediation technologies had been applied. DEC