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i sample showed the presence of xylene, TPHg, & MTBE; benzene, ethylbenzene, & toluene were below detection limits. Refer to TABLE V for details. I PLATE VIII shows lines of equal concentration of benzene in water samples collected in July &August. Levels are the highest in MW-1 at 51 ug/L, which is nearest the site of the removed UST. MW-2 & MW-3 were ND. MW-4 measured 0.6 ug/L; MW-5 measured 0.4 ug/L; and MW-6 was ND. PLATE IX shows concentrations of ethylbenzene. The patern is very similar to that for benzene; MW-1 had the highest levels, with smaller amounts in MW-4 & MW-5. MW-2, 3, & 6 were ND. PLATE X, for toluene, has a shape very close to that for benzene & ethylbenzene. MW-1 measured 4.0 ug/L, MW-2 was ND, MW-3 measured 0.5 ug/L, MW-4 0.8 ug/L, and MW-5 1.0 ug/L. MW-6 was ND. PLATE XI shows the pattern for xylene. MW-1 continues to have the highest level - 64 ug/L; MW-3 measured 3.0 ug/L; MW-4 had 16.0 ug/L, MW-5 had 8.0 ug/L. MW-6 measured 0.5 ug/L; it had been below detection limits for benzene, ethylbenzene, & toluene. Based upon the data, it appears that the zylene plume may continue offsite to the north. MW-2 continues to be ND. PLATE XII shows lines of equal concentration for TPHg. MW-1 recorded the highest level at 1670 ug/L; MW-3 had 264 ug/L, and MW-4 had 224 ug/L, and MW-2 was ND. The level measured in MW-5, 635 ug/L, is much higher than expected when compared to the levels in MW-4. MW-6 measured 88 ug/L, which again indicates that the gasoline plume may extend a short distance off the property to the north. PLATE X111 shows the isoconcentration lines for MTBE. The shape is similar to the others, and appears to extend off the property to the north. MW-6 measured the highest levels of any of the wells, 230 ug/L, which has not been the pattern for the other compounds. An analysis of the latest data presents a different picture than assumed from previous work. MTBE, which had only been measured in one unconfirmed water sample from SP-3, is present in both soil & water samples from MW-4, 5, & 6. It was also detected in the water sample from MW-1. Assuming that the source was the removed UST, the MTBE plume has been carried to the north by groundwater movement. This is not unexpected since the compound is very soluble in water and has been shown to travel a long way from its source. 40 Xylene &TPH as gasoline have migrated farther downgradient than the lighter benzene, ethylbenzene, &toluene. The mechanics of this are not clear. I Wm. J. Hunter&Associates 6