Laserfiche WebLink
I LABORATORY TESTING: <br />Routine classification and index property testing was <br />1 performed for the varid~j,s,~ soil types encountered on site, <br />~. <br />including an analysis of" soil gradation and plasticity <br />characteristics. In addition, direct shear testing was performed <br />on samples of the colluvial soil (landslide debris), man-made <br />fill materials, and the weathered shale bedrock. <br />1 <br />DESCRIPTION OF STRATA: <br />In general, the nature of the soil profiles utilized in <br />slope stability modeling consisted of a deposit of colluvial soil <br />of varying thickness overlying a bedrock surface consisting of <br />1 interbedded sandstone, siltstone and shale. The colluvial <br />material would typically terminate at the base of the slope in a <br />thick deposit of river terrace or alluvial soil. The vertical <br />thickness of colluvium utilized in the stability models would <br />typically be on the order of 35 feet. However, the thickness of <br />this layer would typically vary, being thinner higher in the <br />profile and becoming thicker near the base of the slope. <br />_I Detailed profile indicating the position and orientation of all <br />1 assumed soil materials are provided in the Appendix of this <br />report. <br />Although no free water was observed in any of the colluvial <br />1 materials on site at the time of drilling, it is assumed, for the <br />J purpose of stability modeling, that a 4-foot thick zone of <br />seepage will develop at the colluvium/bedrock interface. A <br />static piezometric level at the base of the slope was assumed at <br />l an approximate depth of 6 feet below the ground surface, as <br />5 <br />