Laserfiche WebLink
<br />• Bedrock - underlies the entire site at varying depth and <br />is assumed to be of sufficient strength to prevent any potential <br />shear surface associated with failure of the waste piles from <br />developing within the bedrock. <br />Alluvial soils fill the valley bottom and underlie the waste <br />piles to a large extent at locations where the valle;r is reason- <br />ably wide. The coarse nature of alluvial sediments results in <br />its having similar physical properties to those of the waste <br />material. <br />colluvial soils are developed on steeper slopes shove the al- <br />luvial valley. Their depth, as it has been discussed in <br />Section 3.1, varies at different locations. It is probahle <br />that colluvial soils cover the alluvium at certain locations. <br />The accurate contact between alluvium and colluvium was <br />estimated. Its accurate determination would require drilling. <br />• Physical properties of individual materials were developed either <br />with the help of simple soil testing or they were based on data available <br />from literature describing similar matererials. A more detailed dis- <br />cussion of physical properties is presented in Appendix A. <br />As can be seen on both sections, it has been assumed for the <br />purposes of the analyses that the waste piles are completely underlain by a <br />layer of colluvial soils at all locations. Since the colluvial soils have <br />the lowest shear strength of all materials at the site, this assumption <br />is conservative. <br />The same general approach has been taken in the stahility analy- <br />sis of each stability section. Factors of safety have been calculated <br />for potential sliding along selected surfaces which represent realistic <br />failure mechanisms for the waste pies. <br />• <br />_ 20 _ <br />