2011-10-31_REVISION - M1976009HR (7)

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Menzer Quarry Corrective Action Amendment Exhibit D October 2011 Page 4 Mining Plan stream channel picking up rock and loading it into a truck that came down the same road. This crude road was very carefully constructed so the large haul truck would be able to get up the road after it had come down the road. After the stream corridor had been cleared of spill rock, the track hoe began to work back up the slope, producing a final grade as it went. Attempts were made to try and remove only the spill rock from the stream corridor while leaving the original rock, but that approach quickly became unworkable. Therefore, most of the rock was removed and then rock was replaced in the stream bed to produce a condition approximating the original, pre -spill condition. Essentially, rock size and density was replaced in a fashion that was similar to the natural rock in the channel downstream from the spill. This was a bit less rocky than the original, but it eliminated a slow spot in the stream flow that often created minor ponding upstream and tended to drain slowly, even before any mining was done or the spill occurred. Rock removed from the east bank, which suffered very little physical damage to the soil, was carefully done so the original land surface was left in place. Basically, each rock was picked up vertically leaving the underlying soil disturbed to the minimal amount possible. Vegetation topgrowth, of course, was damaged, but the root mass was left undisturbed. As the plants are mostly streamside shrubs, the roots should quickly send up new shoots. This will lead to a rapid recovery of the stream shore much like it originally was. Isolated, outlying rocks were removed by hand. It is very important to note that at no time after the spillage occurred or during the rehabilitation process did Turkey Creek produce any flow. Therefore, there was no need to make provision for sediment control or other activities to protect the water resources. No water was ever encountered during the entire process. As the track hoe moved out of the canyon and back up the slope, removing spill rock as it went, it began to excavate and shape the lower portions of the spill slope. It was then that it was found that no matter how deep the track hoe reached it did not hit bedrock. The original intent was to create a somewhat rocky final surface similar to the scree slope that had been there. Unfortunately, that became impossible as the underlying material seemed to extend deep into the ground. The more the track hoe dug into the material the more the final configuration was looking more like a bench than a slope. About 35 feet west of the stream, a vertical wall of bedrock was encountered. It was at that time that it was decided to leave a broad, nearly level bench beside the stream channel, backed by solid rock on the west and the south. The bench would start at about 5 to 6 feet above the assumed stream channel mean water line. This was on the north end of the bench. The bench would then have a very gradual uphill slope to the south until it met the bounding bedrock on the south. Adding the rise of the bench and the decline of the stream channel, the south end of the bench would have a height of about 12 to 15 feet above the assumed stream channel mean water line. The boundary between the bench and the stream would then be lined with large rock to reduce westward cutting of the stream during high water. As the track hoe moved to the top of the wall on the west side of the bench, it completed the excavation of the bench area leaving solid rock bounding the bench. Thus the channel was restored in the same location and configuration with regard to gradient as it was before the slide, but with