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M03030GE • formational material was encountered in test boring 2 to a depth of about thirty (30) feet, the maximum depth or the test boring. Free subsurface water was not encountered in test borings at the time of our field study. We anticipate that the free subsurface water may become perched on the surface of the formational material with time and may be variable with time. It is difficult to predict if unexpected subsurface conditions will be encountered during construction. Since such conditions may be found, we suggest that the owner and the contractor make provi- sions in their budget and construction schedule to accommodate unexpected subsurface conditions. 3.0 SLOPE STABILITY l~ • The stability of any slope is dependent on many factors. Typi- cally the stability of a slope is analyzed by calculating the anticipated gravitational forces that tend to drive the mass of soil downhill and the anticipated internal strength of the soil along the expected plane of failure that will resist the downhill movements. .If the driving forces are equal to or greater than the resisting forces then failure is imminent. We understand that the minimum theoretical calculated factor of safety of 1.3 is consid- ered by the Division of Minerals and Geology as a minimum factor of safety for a slope. to be considered. Our stability analysis is based on this understanding of a minimum theoretical calculated factor of safety of 1.3. Factors that have an adverse influence on slope stability can generally be classified as those that increase the stress (driving force) on the system or decrease the strength (resisting forces) of the soil. Our stability analyses of the existing reclamation fill slope was based on the Bishops Method of Slices. This method is based on the assumption that the slope soil mass will fail in a rotation mode on a circular arc plane. In this method of analysis the mass of soil is divided into vertical slices. The forces acting on each slice are evaluated from the equilibrium of the slices; that is, the forces that tend to drive the slice downhill and the forces that tend to resist the movement of the slice. The equilibrium of the entire mass is determined by summing the driving and summing the resisting forces acting on all slices and comparing these forces. Our slope stability analysis was performed using "Slope Stability Analysis'I program by Geosoft computer software. Our slope stabil- ity analysis considered one (1) cross section provided by Mr. 3 llam6ert ana ~,~~ociate~ CONSULTING GEOTECH NICAL EN GIN EENS AND M ATE ALAI TESTING