Laserfiche WebLink
TABLE 1. SOIL CHEMICAL DATA <br /> Sample TPHG Benzene Toluene Ethylbenzene Xylene MTBE <br /> No. mg/kg ---------------------------- ug/kg ---------------------------------- <br /> B-8-2 ND ND ND ND ND ND O <br /> B-9-2 ND ND ND ND ND ND <br /> B-10-2 ND ND ND ND ND ND <br /> B-12-2 ND ND ND ND ND ND <br /> B-13-2 ND ND ND ND ND ND <br /> TABLE 2. GROUNDWATER CHEMICAL DATA <br /> Sample TPHG Benzene Toluene Ethylbenzene Xylene MTBE <br /> No. --------------------------------- ug/1 --------------------------------------- <br /> B-8 ND ND ND ND ND ND d ti(�VI <br /> B-9 ND ND ND ND ND ND <br /> B-10 ND ND ND ND ND ND�h" <br /> B-11 ND ND ND ND ND ND � <br /> B-12 ND ND ND ND ND ND <br /> B-13 ND ND ND ND ND NDy,y <br /> ND - Not Detected ug/1 - microgram per liter ug/kg- microgram per kilogram <br /> mg/kg - miligrams per kilogram <br /> Discussion <br /> The information collected during this study indicates that the dissolved contaminant <br /> plume is limited in extent. Field evidence of suspected degraded contaminants were <br /> observed at the capillary fringe at Borehole B-9. This corresponded to the sandier <br /> sediment and more rapid groundwater entry into boreholes B-9 and B-12. However, <br /> chemical analysis showed that petroleum contaminants were not detected in either <br /> soil or groundwater. <br /> A relatively slow groundwater movement is inferred from historic groundwater <br /> monitoring wells measurement data Overall site groundwater movement is <br /> northerly. This groundwater measurement data also indicates flat flow gradients <br /> which, together with clayey aquifer strata, appear to have limited migration of the <br /> plume. This could also account for the apparently anomalous contamination <br /> spreading slightly upgradient of the former tank pit at Borehole B-5. <br /> These data show that TPHG and BTEX contaminants are not present beyond <br /> downgradient Borehole B-3 (sampled in December, 1994) In our opinion, the <br /> distribution of contaminants indicate that gasoline was leaked in the vicinity of, and <br /> has only migrated a short distance from, the former tank location (see Figure 3) <br /> M&MAutomotrve Project No 4070-T Page 5 <br />