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Q <br /> RESULTS AND-CONCLUSIONS <br /> The results of our analysis indicate that the existing tailings embank- <br /> ment is stable against major slope failures. Based on the laboratory and <br /> stability analysis a minimum factor of safety of 1 .2 was obtained against <br /> C.� <br /> a major slope failure occuring through the tailings in the embankment. <br /> However since the conditions under which the earthen berm were constructed <br /> had to be assumed, it can be expected that minor failures and/or sloughing <br /> of the earthen berm will take place if suitable compaction was not utilized <br /> during placement. This analysis assumed that the ponding height of the <br /> tailings was to the elevation of the top of the existing earthen berm (i.e. <br /> 0 <br /> approximately 2' higher than was existing at the time of the test drilling). <br /> Therefore, additional tailings may be added to this elevation without decreasing <br /> the stability of the embankment. The analysis also assumed that the sand <br /> C' <br /> tailings were essentially dry. The factor of safety at the critical circle <br /> will be reduced to failure if saturation of the sands takes place as a <br /> result of ground water rise of over 5 feet at the toe. <br /> In addition to the above analysis, an analysis was conducted to determine <br /> the effects of increasing the total height of the tailings embankment 6 <br /> feet above the present elevation (i.e. equivalent to approximately 6 months <br /> of tailings). The effects of this condition, assuming a saturated slime <br /> condition and the water table approximating that boundary layer bordering <br /> 0 the slimes, would result in a minimum factor of safety of 1 .15 from increasing <br /> the total pond height an additional 6 feet. Any increase in height above <br /> this will result in a factor of safety reduction in by overloading the <br /> 0 slimes. The above analytical analysis was done under static loading conditions. <br /> -6- <br />