ARCHIVED REPORTS XR0009862 - Laserfiche WebLink

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I the samples for benzene, toluene, ethylbenzene, and xylenes (BTEX), total petroleum hydrocarbons as gasoline (TPHg), and total petroleum hydrocarbons as diesel (TPHd) using EPA ' methods 8020 and modified 8015, respectively Split samples were analyzed for total lead by Sequoia Analytical of Redwood City, California (DHS cert #1210) using EPA methods 6010 and 239 2 for soil and water, respectively Analytical results of soil and groundwater samples are summarized on Tables 3 and 4, respectively Laboratory data sheets are included in ' Appendix II ' 5.0 SUBSURFACE CONDITIONS 5.1 Soil Soil encountered beneath the site consists primarily of lean clay (CL) from ground surface to ' approximately seven feet below grade, clayey sand (SC) with silty sand (SM) and silt (ML) from seven feet to approximately 15 feet, and CL to fat clay (CH) from 15 feet to 28 feet, the maximum depth explored During drilling, the supervising geologist noted slight to moderate petroleum hydrocarbon odors at the water table interface in borings SB3, SB5, S136, and S138, while slight to strong odors were noted in boring S137 No odors were noted in borings SBI, SB2, SB4, S139 or previously installed wells T1, T2, and T3 PID readings (see logs) ranged from 0 in the borings with no odor to a maximum of 117 ppm in SB7 ' Analytical results verified the presence of residual hydrocarbons in sods at the water table interface from borings SB3 (140 ppm TPHg), S135 (60 ppm TPHg), SB6 (1 3 ppm TPHg), and IS137 (1,800 ppm TPHg) In addition, petroleum hydrocarbons were detected at 4 5 feet below grade in boring SB3 (I 1 ppm TPHg) No petroleum hydrocarbons were detected in the samples i collected from SB6 and S137 at 11 0 feet Analytical results for lead were relatively uniform among samples and are believed to be representative of background levels No petroleum ' hydrocarbons were detected above the method detection limit in borings S131, SB2, SB4, S138, 150087/8 053194 FNL 5