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(VYAT4t <br /> A S S O C I A t E 5 I N C <br /> Task 2: Soil Excavation, Transport, and Disposal <br /> Prior to completing the subsurface investigation, ATC will supervise the excavation of the <br /> impacted backfill material located in the former U$T location. For estimating purposes, ATC is <br /> assuming that excavating a hole twelve feet wide, twelve feet long, and twelve feet deep will <br /> remove all of the impacted backfill material. Excavated backfill material will be field screened <br /> with a photoionization detector (PID) to confirm that all impacted soil has been removed. The <br /> impacted backfill material will be immediately transported to Forward Inc. landfill in Stockton and <br /> stockpiled at the landfill. Composite soil samples will be collected from the impacted backfill <br /> material as it is loaded into the trucks. <br /> Soil samples will be placed on ice and transported under chain-of-custody documentation to a <br /> State-certified laboratory for analysis. Samples will be analyzed for total petroleum hydrocarbons <br /> as gasoline (TPHg, EPA Method 8015), total petroleum hydrocarbons as diesel (TPHd, EPA a <br /> Method 8015), benzene, toluene, ethylbenzene, and xylenes (BTEX, EPA Method 8020), and <br /> total lead. Once analytical results have been received, the data will be supplied to Forward Inc. <br /> landfill and they wiII place the soil in the appropriate location in the landfill based on the analytical <br /> results. <br /> The excavation will be backfilled with clean pea gravel from twelve feet to five feet below ground <br /> surface (bgs). The remaining five feet will be backfilled with clean Class H aggregate base ' <br /> material to the surface. The Class II material will be compacted as it is placed in the excavation. <br /> It is anticipated that the excavation, disposal, and backfill activities will be completed in one long <br /> day. Traffic control measureswill have to be taken in the alley area to allow access for the trucks <br /> and prevent public access to the excavation area. <br /> PHASE TWO <br /> i <br /> Task 3: Installation of Three Borings and Three„Monitoring Wells <br /> ATC will supervise the advancement of three soil borings, collect soil samples, and complete the <br /> borings as groundwater monitoring wells. Three borings will be advanced using; a hollow stem <br /> auger equipped drill rig. A field geologist will be present to log all drill cuttings and soil samples. <br /> Descriptions of soil types encountered and sample collection intervals will be recorded on <br /> boring/well logs. Soil samples will,be collected at five foot intervals or significant changes in <br /> lithology, field screened with a PID, and at least two samples from each of the three borings will <br /> be submitted for Iaboratory analysis. All drill cuttings will be drummed and stored on-site pending <br /> laboratory results. <br /> Placement of Borings and Wells <br /> To determine the horizontal extent of soil and groundwater contamination, two soil borings will <br /> be advanced to approximately 57 feet bgs and completed as groundwater monitoring wells. To <br /> w:Ipmpo=11p910001p91015b.doc 2 <br /> II <br />