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- 5 - <br />• of the contact between the landslide deposits and intact bed- <br />'' rock. This interpretation is shown in five profiles along <br />' ~! individual mine entries Nos. 1 through 5, presented on Plates 2 <br />~; through 6. The line showing the probable limit of landslide <br />j! deposits is shown on these profiles. The location of the contact <br />is based largely on ARCO's interpretation. It is only an inter- <br />. I pretation and the actual location of the contact can vary. <br />The interpretation shows that the excavation of the mine <br />portal bench will be largely in soil (landslide) deposits and I <br />that the portal cut will be 21so excavated in soils. <br />We believe that, for the design purposes, it should be as- <br />sumed that all excavations within the landslide area will en- <br />counter soils of a similar character as identified during our <br />drilling program and that the bedrock formation will be encoun- <br />tered only locally. It cannot be excluded that the bedrock form- <br />. ations, when encountered, may not be in-situ, but that they may <br />have been also transported by old slide movements. <br />I~ <br />2.2 HYDROLOGIC CONDITIONS <br />We feel that hydrologic conditions are of a crucial import- <br />ance for the stability of the existing landslides, for the <br />sucessful completion of the proposed construction, and for the <br />long-term stability of the.. area. The adverse climatic conditions <br />of the 1980 spring demonstrated clearly that a complete satu- <br />ration of the soils (the ground water coinciding with topographi- <br />cal surface) can occur at.numerous locations. It was also evi- <br />dent that some steeper slopes, when saturated, may become un- <br />stable. The excavation of some very low cuts caused sliding of <br />an important extent. <br /> <br />~i,IC1,D O01'Y4iM6 K <br />