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Grand Island Resources, LLC Page 8 <br />Idaho Tunnel Portal – Slope Stability Analysis <br />Applied GeoLogic LLC 5/7/2020 <br />Photograph 6 – Regolith and colluvium exposed in the right (north) wing wall of the portal excavation. <br />GIR has explored the first 200 ft of the Idaho Tunnel in order to investigate the corresponding ground <br />conditions that can be anticipated during the rehabilitation efforts. Starting from the back of the last steel <br />set, the existing ground support consists of timber sets with full lagging on the back and ribs for the next <br />41 ft, followed by rock bolts and chain link mesh. The timber sets retain loose soil and rock, obscuring the <br />undisturbed ground. Loose blocky material has also fallen onto much of the chain link and pulled it from <br />the roof in places. The ground mass and rubble observed consists of granular fragments of decomposed <br />rock mixed with blocky pieces of rock, transitioning more to angular pieces of highly fractured weathered <br />rock with increasing distance into the tunnel. Other than a change in the type ground support previously <br />employed, there does not seem to be a well-defined point in the tunnel at which a change from <br />“Decomposed Granite” to “Weak Hard Rock” occurs. It appears to be a gradual transition with some of <br />each type of material found within the other. <br />At approximately 200 ft from the new portal there is a collapse after which, the rock exposed in the sides <br />of the tunnel (ribs) appears to be fresh and less fractured gneiss, the tunnel exhibits a more regular 6 ft x <br />6 ft opening, and there is no ground support visible. This is interpreted as the “Hard Rock with Fractures” <br />indicated on Figure 1.