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Quik Stop No 121 Closure Report • CCI Project No 12118 Page 8 and industrial wells within a 2,000—foot radius of the subject site The survey found 4 wells within the search area One well is located at the First Christian Church, located northwest of the intersection of Louise Avenue and Union Road More specifically, the well is located 350 feet west of Union Road and 200 feet north of Louise Avenue The well, which is used for domestic purposes, extends to a depth of 158 feet A second well is located west of the subject site, at the Union Cemetery The well is located approximately 225 feet south of Louise Avenue and 150 feet west of Union Road The depth of this well is not known The well is most likely used for irrigation purposes City of Manteca Well # 15 is located approximately 1,000 feet southeast of the subject site This municipal well is located at the corner of Franciscan Way and Agate Avenue The well has two perforated intervals, at 140 to 180 feet and 205 feet to 265 feet A fourth well used for irrigation purposes is reported to be located 300 yards east of Union Road, on the north side of Louise Avenue CCI was unable to physically locate this well There are no other sensitive receptors located within a 2,000-foot radius of the site There are no nearby lakes or rivers The San Joaquin River is located approximately 7 miles south of the site 4 REMEDIATION OF SOIL AND GROUNDWATER • From October 1998 to October 2001, CCI installed a total of 13 groundwater monitoring wells at on and off-site locations Ten of the wells were installed into the shallow A-aquifer and three of the wells were installed into the B-aquifer at the site Based on the information obtained during several investigations conducted at the site between October 1998 and January 2002, the extent of soil and groundwater contamination had been defined There was virtually no soil contamination detected above the capillary fringe of the fuel tank area or in the soil borings and monitoring wells installed around the site All detectable soil contamination was found between 10 and 20 feet, with the majority of the compounds being detected at 15 feet, which was at or below the site water table This soil contamination was most likely due to a smear effect from a rising and lowering water table The history of soil sample analysis is presented in Tab 2, Table 3 The groundwater data collected over several quarters indicated groundwater was impacted with TPHg and MTBE, mainly in the vicinity of Quik Stop Markets' fuel tanks on the southeast side of the site, near monitoring wells MW-3 and RW-1 Goundwater contaminant contour maps from January 2002 to October 2002 show the maximum extent of groundwater contamination at the site The highest concentrations of TPHg and MTBE were in the vicinity of wells MW-3 and RW-1 Low concentrations of TPHg and MTBE were occasionally detected in the shallow water samples collected from perimeter monitoring wells MW-5 and MW-8, located on the south and southwest sides of the site The other site perimeter wells (MW-1, MW-2, MW-7, MW-11 & MW-12) were all reported to be free of detectable petroleum hydrocarbons Contaminant