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Ob/03/1999 09 51 7078382323 GALLARD© AND ASSOC PAGE 12 Ltmited Soil sod Gronadwater R"-05/24/99 Page& Westerst Od&SprE!d!M site Project No 024 98 I6.0 SITE SOILS The site soils encountered beneath the site property durmg drilling consisted of brown silty sand to a depth between 8 to 9 314 feet bgs followed by an underlying layer of grey to brown sand,with the ' exception of boring B-3,which did not contain a sand seamy at that elevation Below these layers of soil at a depth of between 12 and 13 feet bgs,a browmssh-grey to browns clayey sand to salty sand was encountered to a depth of approximately 40 feet bgs ifowever,a grey sand layer approxmaately 9 feet thick(at 13-2-)and a half-foot thick grey silty clay layer(at B-4), were encountered followed by a grey silty Clay anal grey-brown sand layer(at 13-2)or a grey sand, grey-brown silty sand, and light ! grey sand layer (at B-4) At the time of sampling, petroleum hydrocarbon odors and soil ' discoloration were noted in the soul samples collected from borings B-1, 13-2, and B-4 commoncing at a depth of approxuriately 14, 4, and 12 feet bgs, respectively Analytical results later confirmed petroleum hydrocarbons witbain the soU at these three locations. No indication of impacted soil was observed or confirmed by analytical results at bortngs B-3 and B-5 ' 7.0 SOIL SAMPLING A total of 20 soil samples were seketcd durrrng the dueling of borings B-1 tbarough B-5 and submitted ' :For laboratory analysis of TPII-d,TPH-k,TPH-g,MTBE, and B'KX The soil samples for bonngs B-2 through B-5 were collected using a 2 if.-foot long, 2-inch I D steel split-spoon sampler containmg three six-inch long stainless-steel or brass liners,while soil samples for boring B-1 were collected using a threeinch diameter, five-foot long split-spoon sampler containing no brass liners Each sampler used was decontaminated before and after each use by using a Tri-Sodium Phosphate wash solution and tap water. The sampler was placed down the boring and driven into the ground approximately 18-triches using a 140-pound Hammer, with the exception of boring B-1, which was continuously-torted Soil sampling intervals and initial sampling mras were used for visual classification of the underlytrig soil The soil sampling nrtmvals were generrally at depths of approximately 5, l 0, 15, 20, 25, 30, 35, and 40 feet bgs Soil saxnples not submitted for laboratory analysis were used for visual identification of the uuderlymg lithology. 8.0 GROUNDWATER SAMPLING ' Because groundwater was encountered in only one of the exploratory soil bo s a total of one groundwater -grab"'sample was collected from burin l-4 After boiiitg B-4 was completed,the ' hollow-stem augers were left in-place for approximately one hour to prevent collapsing of the borehole and to assure that a representational groundwater 'grub"sample could be collected from the borehole Groundwater samples were collected by placing a disposable bailer down the center of the auger to allow for an it situ water sample collection The water sample was placed in three 44 Ml VOA vials containing HCL as a preservative for TP14 g and/MTBE analysis and a ane-liter amber bottle for TPH-d and T H k analysis The sample, vials were filled with the collected ' groundwater until they overflowed, and were then sealed with Teflon-lined sepia caps so that no air . was trapped in the vial or bottle. Once flied, each of the samples were mverted and tapped to test for air bubbles The groundwater water samples were contained in vials approved by the US EPA. ' and the SI~BRWQCB in accordance wtth EPA SW 849 Each smWe container was properly labeled and contained the sample number, and date of sampling