Laserfiche WebLink
south of the excavation; both borings are in the presumed upgradient direction from the tanks <br /> according to the San Joaquin County Flood Control Map. The purpose of these borings is to <br /> provide an indication of the lateral extent of soil contamination. The fourth boring will be drilled <br /> east of the excavation,and will be drilled to groundwater so that a water sample can be collected. <br /> The precise,depth of groundwater in,the area is unknown at this time,but it is our understanding <br /> from Mr. Hartzell that he recently measured the depth at approximately 80 feet in a domestic well <br /> on the property. <br /> Soil samples will be collected at 5-foot intervals and boring logs will be prepared. We estimate <br /> that twenty samples will be preserved for laboratory analysis,and five of these will be analyzed <br /> for gasoline oxygenates using EPA method 8260. Selected shallow samples will also be analyzed <br /> for total lead. <br /> Augers will be steam-cleaned between borings,and drill cuttings will be placed on plastic <br /> sheeting pending laboratory analysis to profile them for disposal. <br /> 3.0 PROCEDURES <br /> 1) Prepare a site-specific Health and Safety Plan <br /> 2) .Submit an application for a drilling permit <br /> 3) Notify PHS/EHD at least 48 hours prior to field work <br /> 4) Drill four vertical borings with 8-inch diameter hollow-stem augers <br /> 5) Collect soil samples at 5-foot intervals and screen for hydrocarbon odors using a portable <br /> PID;describe the samples on the boring log <br /> 6) Preserve the bottom sleeve of each sample on ice for possible laboratory analysis <br /> 7) Decontaminate the sampling and drilling equipment between borings <br /> 8) Place drill cuttings on plastic sheeting <br /> 9) Collect a groundwater sample through the augers from the deepest boring <br /> 10) Use a tremmie pipe to backfill the borings with.cement grout <br /> 11) Transmit selected soil and water samples to a state-certified laboratory for analysis of: <br /> Total Petroleum Hydrocarbons as gasoline <br /> Benzene,toluene,ethylbenzene,xylene, and MTBE <br /> Gasoline oxygenates <br /> Total lead <br /> 12)Prepare a Preliminary Investigation and Evaluation report, signed by a California <br /> Registered Geologist <br /> i <br />