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7-Eleven/Stockton 17 February 1990 Maps depicting the distribution of dissolved hydrocarbons in the groundwater, based on laboratory results from monitoring well samples from October, November, and December 1989, are presented on Figures 8, 9, and 10. The distribution of detectable dissolved-hydrocarbons in the monitoring wells sampled during this quarter was confined to MW-1, MW-9, PW-1, PW-2, and PW-3- The samples collected from MW-1 contained detectable levels of dissolved hydrocarbons in all sampling rounds this quarter. Results showed concentrations of TPH-as-gasoline in 14W-1 ranging from 43 to 450 parts per billion (ppb) . This is :-educed from the levels detected during the previous reporting period. Results from analyses of samples collected from NW-9, PW-1 and PW-3 showed they contained levels of dissolved hydrocarbons in at least one sampling round during this Igmarter. TPH-as-gasoline was detected in samples from MW-9 for the first four sampling rounds of this reporting period. TPH-as-gasoline was detected in the samples from PW-1 for the first two sampling rounds. TPH-as- gasoline was detecited in PW-3 on one occasion. The maximum concentration reported in samples from these wells was 112 ppb. All other monitoring and pumping wells contained non-detectable levels of dissolved hydrocarbons in all six sampling rounds. The results nf laboratory analyses of groundwater samples collected from the domestic wells surrounding the site indicate that all wells contained non-detectable levels of dissolved hydrocarbons in all sampling rounds. sporadic unconfirmed occurrences of low concentrations of dissolved hydrocarbons have been reported in the past. Tabulations of the laboratory results - for TPH-as-gasoline have been compiled for the monitoring and pumping wells (Table 3) and for the domestic wells (Table 4) (Appendix A) . [a CROCNEAVATER TECHNOLOGY.INC