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1 <br /> + SUBSURFACE CONDITIONC <br /> Subsurface soil and ground water conditions at the site wae explorad on January 10, 1994 <br /> 1 by ezcavating 10 test pits (TP-1 through 1'P-10) to depths ranging from about 7 W 9 feet bdow <br /> the ezisting ground surface. 'Ibe approximate locations of the test pib are ahown in Figure 2. <br /> I Logs of the ezplorations, geotechnical laboratory test results, and descriptions of the subaucface <br /> � ea�ploration and geotecbnical laboratory testing programs ue prccented in the appendix. <br /> 1 'It�e subsurface exploratioas were completed to obtain data in orda to provide gootechnical <br /> recommendatioas for site development. '11ie subsurface materials enoountered were quslitatively <br /> evaluated in the field for visual evidence of the presence of contamination by hazacdous <br /> 1 substances. Field screening consisting of visual,water shcen and headspace vapor acrcening wa4 <br /> conduaed on soil samples from each test pit in order to help idendfy any potentially contaminated <br /> I soil. The field screcning did not iudicate the presence of oontamination in any of the explorstiona <br /> and soil samples were not obtaine3 from the exploradoas for chemical analyses. Field screeoiag <br /> � . methods aze described in the appendix. <br /> 'Eae ahallow subsurface conditions, as encountered in our exploratioas, are relatively <br /> uniform across the site. In genaal, the test pits encountered a surficial layer of forest duff 0.2 <br /> 1 to 0.3 fcet thicF underlain by weatherad and unweathered gtacial till. The glacial till geoerally <br /> consists of relatively impermeable silty sand with gravel that has been overconsolidated as the <br /> � result of being overridden by glacial ice several thousand feet thick. Cobbles and bouldera, <br /> although not encountered in our test pits, commonly occur in till and may be encountaed at this <br /> site. We encountered brown, loose to medium dense, weathered dll eactending to deptLs ranging <br /> I from about 1 to 2.5 faet in our test pits. Brownish gray, dense to very deose, unweathaed till <br /> � underlies the weathered till and extends w the completion depths of our test pits. At the location <br /> � of TP-3, the dll contains sand lenses between depthc of about 2 and 4.5 feet. Caving of the test <br /> pits walis was only observed in TP3 and TP-4, where minor to moderate caving was obsaved <br /> � associatefl with ground water seepage as discussed' :low. <br /> Ground water seepage was only observed in TP-3 and TP-4. At these locatioos, moderate <br /> ground water seepage was observed between depths of about 1.5 and 4.5 feet within localizad <br /> I zones of material having relatively higher permeability. 'Ihis seepage does not reflax d►e <br /> regional ground water table, which we eacpecc is at least sevecal tens of fe� below the yround <br /> surface of the site. Rather, this water represents locally"perched" ground wata that accumulates <br /> � within the till and "bleads" from the more permeable sand lensrs. 'lbe voluma of such seepage <br /> is generaliy small and may not be encountered during the late summet and early fall. <br /> IADJACENT PROPERTIES <br /> � 1Yie site is tocated within an industrial/business pazk of very recent development. Adjacent <br /> properties on all sides of the subject site are presently undeveloped. <br /> l <br /> IG e o E n Q i n e e r � 4 Fle No.32D6-002-AO1N20394 <br />