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Water samples collected from domestic wells have been analyzed for the presence of TPHg, BTEX, FOCs, 1,2-DCA, and EDB Since water samples collected from DW-2 contained reportable concentrations of MTBE, the well was taken out of service and replaced with DW-2R Domestic well DW-1 is considered a public water supply because it services a retail store (Ranch Market) The nitrate concentrations detected in water samples collected from DW-1 exceeded the drinking water standards A replacement well (DW-IR) for DW-1 was constructed in February 2004 and put in service sometime between July 7 and 11, 2004 for the domestic water supply to the Ranch Market ' Well DW-1 has been disconnected and is inactive In accordance with a letter from San Joaquin County Environmental Health Department (SJCEHD) dated February 26, 2004, sampling of well DW-1 has ceased 25 Free Product ' Free product was first observed in groundwater monitoring well MW-3 during the Fourth Quarter 2003 sampling event conducted in January 2004 Upon discovery of the free product, Geocon began frequent monitoring of the product level and bailing to remove it Measured product thickness ranged from an initial maximum of 0 5 foot on January 9, 2004 to 0 012 foot on February 9, 2004 ' On January 30, 2004, Geocon purged well MW-3 in an attempt to create a cone of depression and draw additional product into the well No increase in free product thickness was noted from the pumping effort As of February 9, 2004 approximately one-half gallon of product had been removed from MW-3 The product odor, color, and apparent viscosity are consistent with weathered gasoline Based on the presence of free product in well MW-3, SJCEHD requested a written summary of the findings and proposed actions Geocon prepared a letter regarding Free Product Discovery and Proposed Actions, dated February 18, 2004 Geocon proposed to continue monitoring and to remove free product USTs were removed from the Site in 1991, and the Site has not operated as a fueling facility since the time of removal In more than five years of groundwater monitoring and approximately 1 5 years of ' remedial activity at the Site (1998-2004), free product had not been encountered until the First Quarter 2004 The discovery of free product after a significant period of time of source removal and ' remedial activity could be indicative of an additional UST at the Site Accordingly, Geocon proposed to perform a records review at SJCEHD and perform a geophysical investigation at the Site to ' evaluate the existence of additional UST(s) In a letter dated February 26, 2004, SJCEHD concurred with Geocon's recommendations In accordance with Geocon's Free Product Discovery and Proposed Actions workplan, a geophysical investigation was performed at the site by Spectrum Geophysics on May 3, 2004 Spectrum did not discover strong evidence of buried USTs at the site Project No 58643-06-01 -4- May 5 2005