2011-10-31_REVISION - M1976009HR (7)

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Mining Plan somewhat smaller rock in the channel to allow the stream to flow more freely through the area. There seemed to be a general recollection that during rare high water flows, sometimes the rocks that were in the stream at the toe of the slope backed up a small pool of water. That water would pool there for a few days before draining out. Thus the new configuration allowed a faster drainage but still had plenty of rock armor to resist erosion. Thus water users downstream will be receiving the full complement of water the stream can generate. As the stream is barren of fish, at least this far up, such action had no impact on fish resources. GEOLOGICAL STRUCTURE OF THE CORRECTIVE ACTION AREA: At this point in a mining plan exhibit, some discussion would be provided of the geological features of the area to be mined Because the area has already been mined, discussion of those features is much more of a report of what was found about the geological structure and any stability problems or other kinds of problems that were encountered. First, it needs to be said that no particularly difficult problems with the geology were encountered. No stability problems were encountered that produced rock slides or slope collapse. The entire project was conducted without encountering such difficulties. It was not actually known before hand what the toe of the slope was composed of. Based upon projections from adjacent land which showed near vertical walls of solid rock, it was assumed that the toe of the slope was also solid rock covered by a veneer of scree and spill rock that was a few feet deep. It was recognized that could present an operational problem with getting to the stream if that veneer was too shallow. Rock might need to be added to provide a wide enough path for the track hoe and then the rock would need to be removed as the track hoe worked back up the slope. As it turned out that was not the case. Once the dozer began to excavate a diagonal path to the stream corridor, the scree seemed to be deep. After reaching the stream corridor and cleaning that up along with some shaping of the channel the track hoe moved back up the path, excavating material behind it. It was found that the toe of the slope was completely composed of loose material backed by a vertical rock wall about 35 feet west of the stream course. At this point it was decided to remove as much of this material as possible while leaving a more or less level bench elevated above the stream channel. What was ultimately found was that the toe of the slope was the remains of an old landslide that had come down the steep slope above and filled a former meander that curved to the west and undercut the slope. Now many other features that had been noted over the years made sense. Before mining the top of the slope above, it was noted that there were overhanging blocks of bedrock near the top of the slope with a slightly concave scree slope below, as described earlier. It looked like it might well have been an old landslide and the rocky channel at the base certainly was consistent with that. The problem was that the amount of material at the toe of the landslide was inconsistent with the apparent amount of rock that had come down. Where had the additional rock gone? There was no evidence that the stream had removed it and so it was just viewed as an anomaly. Now it is known where the additional rock went - it filled the old meander, dammed the stream and forced a new channel to form near the current channel Menzer Quarry Corrective Action Amendment Exhibit D October 2011 Page 5