ARCHIVED REPORTS XR0006812 - Laserfiche WebLink

Home Browse Search

MW2. Benzene (0.020), toluene (0 022 ppm), ethylbenzene (0 0050 ppm) and xylenes (0.027 ppm) were detected in soils from SBI Benzene (0.010 ppm) was detected in the soils collected tfrom SB2, and xylenes (0.026 ppm) were detected in soils collected from SB8. Chromium (41 ppm), lead (8.4 ppm) and zinc (67 ppm) were detected in the soils collected from the soil boring ' drilled near the waste oil tank pit (SB11). No other petroleum hydrocarbon analytes were detected above method reporting limits (Table 1) 5.2 Groundwater Prior to development, purging and sampling, depth to water data was collected (Table 2). Subsequently a groundwater gradient map was created (Figure 4). The gradient magnitude is ' 0.006 ft/ft or 30 ft/mile in a northeasterly direction This gradient direction and magnitude is consistent with other Tracy area sites. Groundwater monitoring and purging data is presented ' in Appendix III lot The wells were purged and developed by pumping, with a bladder pump, a minimum of 3 well and casing volumes from each well Groundwater samples were collected after EC, pH and temperature had stabilized. Groundwater samples were analyzed for BTEX, TPHG and TPHD by EPA methods 8020 and modified 8015, respectively Moderate to high levels of dissolved petroleum hydrocarbon analytes were detected in wells ' MW I and MW2 (Table 3) No analytes were present in MW3. Detection limits were increased during sample analysis in samples collected from MW1 and MW2 due to the high levels of ' constituents in the samples 6.0 CONCLUSIONS ' 6.1 Soil impact Laboratory analysis of soil samples indicates that the extent of petroleum hydrocarbon contamination in the soil has been defined The lateral extent is confined to a narrow zone beneath the former product lines, beneath the former waste oil tank (TP2), and around the l R-012792 LF 6