Laserfiche WebLink
�-(YVATC <br /> ASS O C I ATE S I N C . <br /> Following soil sample collection, soil borings SB3 through S135 were backfilled with neat <br /> cement grout to the ground surface. <br /> �r Gasoline Tanks <br /> k <br /> On February 23 and 24, 1999, ATC supervised the advancement of four soil borings (SB6, SB7, <br /> SB8, and SB9) in the vicinity former gasoline USTs. Drilling was conducted utilizing a hollow <br /> stem auger drill rig. Soil borings SB6 through SB8 were advanced and sampled to 36.5 feet bgs. <br /> Soil boring SB9 was advanced and sampled to 41.5 feet bgs. Soil samples were collected at five- <br /> foot intervals or significant changes in lithology, using a 2-inch diameter split-spoon sampler <br /> containing three brass tubes. A field geologist logged drill cuttings and soil samples utilizing the <br /> �. Unified Soil Classification System. <br /> An FID was used as a field-screening device for the detection of petroleum hydrocarbon vapors <br /> in drill cuttings and cored soil samples. Descriptions of soil types encountered and sample <br /> collection intervals are included on the boring logs contained in Appendix B. <br /> �. Following soil sample collection, soil borings SB6 through SB9 were backfilled with neat <br /> cement grout to the ground surface. <br /> R ' <br /> 2.2 Soil SampleAnalysis <br /> Selected soil samples were placed on ice, and transported under chain-of-custody to Sequoia <br /> Analytical (ELAP #1210) of Redwood City, California for analysis. The soil samples submitted <br /> from the former pipeline and diesel UST locations (borings SBI through SB 5) were analyzed for <br /> TPHd by EPA Method 8015 and BTEX by EPA Method 8020. Samples submitted for <br /> laboratory analysis from the borings in the vicinity of the former gasoline USTs (borings SB6 <br /> • through S139) were analyzed for TPHg by EPA method 8015, BTEX by EPA 8020, and fuel <br /> oxygenates by EPA 8260. <br /> The analytical results for soil samples are summarized in Table 1. Laboratory data sheets and <br /> ._ <br /> chain-of-custody documentation are included in Appendix C. <br /> 3.0 SUBSURFACE CONDITIONS <br /> L. <br /> r <br /> 3_1 Geology <br /> Soil in borings SB 1 through SB5 consisted primarily of fine soils including silt (ML) and clay <br /> (CL) to a depth of approximately 16 to 20 feet bgs. Under 20 feet bgs, soil lithlogy included <br /> sand (SM to SW), clay (CL), and silt(MH)to approximately 36.5 feet bgs. <br /> L <br /> ` w:1172421reportslsumwe1.doc 4 <br /> 1.. <br />