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03 April 2002 AGE-NC Project No. 97-0333 Page 3 of 12 concentrations as high as 140,000 µg/1 and BTEX constituents at concentrations as high as 28,000 µg/1;water samples collected from wells MW-1,MW-2 and MW-3 detected MTBE at concentrations as high as 980,000µg/1 and a water sample collected from MW-1 detected ' TAME at a concentration of 580µg/1.No other fuel components were detected by laboratory analysis. Analytical results are summarized in Tables 2 and 4. Results of the June 2000 investigation were reported in Quarterly Report- Third Quarter 2000 dated 20 September 2000 prepared by AGE. • August and September 2000-AGE conducted a sensitive receptor survey to locate potential ' vertical conduits within a 2,000 foot radius of the site. The results of the sensitive receptor survey located a municipal water well(City of Manteca Well No. 4)located approximately 1,900 feet northwest of the site near and a second municipal water well (City of Manteca Well No. 5) located approximately 1,500 feet south of the site. Results of the investigation were reported in Sensitive Receptor Survey dated 08 September 2000 prepared by AGE • December 2000-Four soil borings(P-7,P-8,P-9 and P-10)were advanced on-site utilizing cone penetrometer testing (CPT) technology to characterize the geologic and hydrologic framework. Based on soil composition data obtained from the CPT soil borings, cross ' sections C-C'and D-D'(Figures 3 and 4)were constructed depicting the general subsurface soil composition on-and off-site.Based on the CPT soil characteristics data,AGE identified four potential hydrologic units informally identified as First Water Zone and located 15 to ' 47 feet bsg,Second Water Zone located 58 to 92 feet bsg, Third Water Zone located 102 to 115 feet bsg and Primary Aquifer Zone located 128 to 150 feet bsg. Significant fuel component and chlorinated solvent-impacted ground water was reported from the First ' Water Zone; while low to moderate fuel component and chlorinated solvent-impact was reported from Second Water Zone, Third Water Zone and Primary Aquifer Zane.Analytical results are summarized in Table 3. Results of the December 2000 CPT investigation were reported in Cone Penetrometer Testing Site Investigation -Fourth Quarter 2000, dated 07 February 2001, prepared by AGE. ' • March 2001 -Ground water extraction well EW-1 and ground water observation well MW-6 were installed at the site for performance of a ground water pumping test. Wells EW-1 and MW-6 were advanced verticallyto depths of 45 feet below surface grade(bsg).Boring EW-1 t was single-completed as a 6-inch diameter ground water extraction well and MW-6 single- completed as a 2-inch diameter ground water observation well with screen intervals between 20 and 45 feet bsg. Soil and ground water samples were not collected during this investigation. Results of the March 2001 investigation were reported in Ground Water Aquifer Pumping Test Report-Second Quarter 2001, dated 15 May 2001,prepared by AGE. ' • April 2001 - Ground water aquifer pump testing was performed at EW-1 to assess general ground water aquifer characteristics and to assess aquifer response to groundwater extraction at a constant pumping rate of 6 gallons per minute;purged ground water was containerized Advanced GeoEnvironmental,Inc.