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In response to the Division's first question 1.(a). One type cross section, showing the <br />maximum vertical relief that may be left at final build out (320') was used to project <br />risk factors of potential failure. The tallest potential vertical run of proposed highwall <br />structure was used to stay as conservative as possible. <br />b) the location of the final highwall build out will be normal to and along the eastern <br />end of the typical cross section A -A' line as shown on the highwall study map. An <br />approximate location of the of upper bench of the final highwall structure is <br />N38.60838 W104.94415 at app. elevation of 7300'. <br />c) The approximate location above has been checked with the TR -02 Reclamation <br />Map and appears to be near the westernmost edge of the proposed set -back area in the <br />northeast corner of Phase One area. <br />2. Foliation measurements of the granite gneiss, while generally following a <br />consistent strike and dip are locally dynamic and will reflect a range of alignment and <br />attitude. The typical cross section was intended to show the general tendency of <br />foliation with relation to the overall highwall geometry. Compressive strength test <br />results show that the foliated rock highwall is at low risk of failure at an overall slope <br />of 1:1, to up to eight 40 bench lifts at overall 40 horizontal run. On a local level, this <br />geometry allows for flexibility to handle a zone of foliation that might need re- <br />alignment of the exposed bench face to facilitate bench face stability over the long <br />term. At worst case scenario, a talus slope at no more than 1:1 slope may be left in <br />place along the mine bench runs. <br />3. Again, Section A -A' is a type section defining the direction perpendicular to the <br />final bench configuration and may be located at various horizontal locations along <br />that directional line depending upon factors mentioned in paragraph 1 above. The <br />residential area above and east of the permit boundaries is obviously outside of the <br />permit boundary and any projections of rock characteristics or structural limitations <br />used to analyze risk of slope failure are gross estimations at best and more than likely <br />over -reaching. A risk analysis of ground stability in the area of the neighboring <br />residents would need to have a much more appropriately acquired data set than is <br />currently available. The analysis of the "fault"zone found within the pit area will be <br />addressed in paragraph 5 below. <br />4. The Spencer -Wright and Sarma methods are two different methodologies that are <br />incorporated into the Galena software to have the capability of analyzing risk factors <br />from different engineering perspectives. The 320'of fmal bench configuration (8 <br />lifts) was used to reflect a maximum build out vertical height. The risk analysis of <br />the overall slope (1:1), is the critical factor considering overall slope stability. For <br />purposes of running comparative risk analysis using different methodologies, it was <br />explained to the investigator by Galena technical support that the program input needs <br />only the overall final slope input. <br />5. There are faults noted on geologic maps of the local area. On the USGS web site, <br />a fault is a geologic structure that is or has been the location of relative movement of <br />bedrock or soils from one side of the fault line compared to the other side. Faults are <br />