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CPT-I penetrated the subsurface to 135 feet bgs. The CPT log indicated that the A Zone aquifer extended from approximately 48 feet bgs to 86 feet bgs The A/B Aquatard from 86 feet bgs to is approximately 94 feet bgs, the B Zone aquifer from from 94 feet bgs to 132 Teet bgs and the BIC Aquatard at approximately 132 feet bgs Based on this log, groundwater samples were obtained from a continuous push sample boring (SB8) at the following intervals A Zone top (48 - 52 feet bgs), A Zone base (84 - 88 feet bgs), B Zone top (94 - 98 feet bgs) and B Zone base (116 - 120 feet bgs) A second CPT test hole was logged approximately 60 feet southeast of CPT-I to verify the continuousness of the A Zone aquifer sands Two other continuous push sample borings were performed and groundwater samples were obtained east of SB8 (SB9 and SBIO). These samples were held at the laboratory to be analyzed only if SB8 samples were positive for TPHg, Benzene, Toluene, Ethyl Benzene or Xylenes (BTEX). All samples were chain of custody delivered to Knff Analytical Laboratory (State of California Certified #2236) Kiff used EPA method 8260B to analyze the water samples for TPHg, BTEX and the fuel oxygenantes MTBE, DIPE, ETBE, TAME and Tert-Butanol SB8 GROUNDWATER SAMPLE RESULTS The SB8 samples were all below laboratory lower detection limits for TPHg, BTEX and the oxygenants (RIPE, ETBE, ETBE, TAME and Tert-Butanol) MTBE tested positive in the 48-52 foot sample (18 ug/L) and the 84-88 foot sample (1 2 ug/L). Both B Zone samples (94 - 98 foot sample and 116 - I20 foot sample) were below laboratory lower detection limits for MTBE (0 5 ug/L), see Appendix E - Laboratory Report Figure 4 is the latest groundwater gradient obtained for this site (December 12, 2000). Figure 4 shows a gradient of 0 002 #t/ft to the northeast with a high water mound at MW2 and a dewatering trough flowing to the northwest from MWI O to MWI Figure 5 is the lateral extent of TPHg using sample results obtained during the December 2000 monitoring event and the samples obtained from SB8 (Apel 26, 2001) Figure 5 shows residual TPHg extending from MW10 to approximately 50 feet past MW12 with complete degradation at CPT 1 (SB8) The vertical extent samples obtained from CTP I (SB8) show that the TPHg does not extend vertically in a downgradient direction Using the calculated TPHg velocity of 28 feet/year and back calculating from the April 26, 2001 sampling of SB8, the water sample represents a plume leaving the site near MW3 around June 1988. MW3 was installed in December 1988 and initial sampling of the groundwater contained free-floating product (yellow in color) This indicates complete degradation of the TPHg plume as it arrives at SB8. Back calculating the December 12, 2000 sample at MW8 (7000 ug/L) to samples obtained from MW 10 The 7000 ug/L TPHg originated near MW 10 between June and December 1994 Three samples were obtained from MWIO during this period and showed the following values; 76,000 W�� 4 R-603 May 2001