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CAAaBRIA from cone penetration testing (CPT) borings SB-12 through SB-16 and SB-18 did not contain methanol These grab groundwater samples were collected at the same depth range (and in some cases shallower and deeper)as the groundwater samples from wells S-1-85 and S-3-84 Methanol is known to degrade rapidly in the subsurface and as a result, does not migrate very far from its source Based on the low concentration (relative to the regulatory level) of methanol detected in groundwater beneath this site, methanol's rapid biodegradation, and the delineation provided by the CPT borings mentioned above, we feel that further investigation for methanol is not warranted at this site 1,2-DCA This compound was added to gasoline as a lead scavenger until 1991 Lead scavengers were a part of a "lead package" that was added to gasoline as an anti-knock package The "lead package" consisted of ethylene dibromide (EDB), 1,2-DCA, and one or more lead compounds Because 1,2-DCA was a component of gasoline in the past it is possible that the 1,2-DCA found beneath the subject site is due to a fuel release at this site However, 1,2-DCA is not a compound that is exclusively found in gasoline It is used in the production of soaps and vinyl chloride It is also used as a solvent and was formerly used as a fumigant Household uses of 1,2-DCA include cleaning solvents, glues,varnishes, and strippers Groundwater samples collected from wells S-1-85, S-3-84, and S-4-83 contained 1,2-DCA concentrations ranging from 45 to 74 ppb (Table 1) Groundwater samples collected from the shallow groundwater monitoring wells have most recently contained 1,2-DCA at concentrations ranging from 2 8 to 540 ppb Grab groundwater samples collected from bonngs during previous investigations at the subject site have contained 1,2-DCA concentrations as high as 1,640 ppb (Table 2) 1,2-DCA has only been detected (0 141 parts per million) in one out of 79 soil samples collected beneath the site The 1,2-DCA analytical results of groundwater samples collected to date are shown on Figure 2 A review of Figure 2 shows a rather uneven distribution of 1,2-DCA in the subsurface Boring SB-8, which contained no 1,2-DCA in groundwater, is located approximately 18 feet north of boring SB-4, which has contained the highest level of 1,2-DCA in groundwater at the subject site North (up/crossgradient) of boring SB-8 (approximately 95 feet away) is boring SB-18, which contained 1,2-DCA at concentration ranging from 25 to 140 ppb It would seem that if the 1,2-DCA found in SB-18 originated from the subject site that it would be present in intermediate sampling locations (SB-8) as well This anomaly is repeated in the groundwater analytical data from borings SB4, SB-10 and SB-15, where SB-10, the intermediate sampling point contains no 1,2-DCA and the SB-4 and SB-15 contain 1,2-DCA These anomalies make it unclear as to whether the 1,2-DCA originates from a fuel release at this site 0797 2