2011-10-31_REVISION - M1976009HR (7)

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Reclamation Plan The bench elevation is closest to the stream elevation on its upper end. There the bench is about 5 to 6 feet higher than the channel. As the stream descends rather steeply across the old landslide, especially toward the lower end, the bench is about 12 to 15 feet higher on the south side of the bench which, again, is bounded by a bedrock cliff. The bench itself rises 3 or 4 feet from the north end (closest, elevation -wise, to the channel) to the south end. The bench surface is therefore quite flat with a general and gentle slope to the north. It is largely composed of fines and smaller stones left over from the landslide debris. Its total depth is unknown, but it is likely not much deeper than the difference in elevation from the bench surface to the bottom of the channel, plus a few more feet. This depth would work out to somewhere around 8 to 12 feet from the bench surface to the bedrock underneath everything. All other grading is above the wall at the back of the bench. That grading is normal quarry edge rounding with smoothing out the humps and valleys a bit. That grading is above the Mining Limit and is a part of the quarry reclamation. Water Resources It is very important to note that at no time after the slide and throughout the rehabilitation did the stream flow. The minor flows all occurred after all the rehabilitation work was completed. Therefore, there was no impact whatsoever on water quantity or quality during the rehabilitation process. Normally, Turkey Creek flows quite well into late June, often into July, and sometimes into August when it normally tends to decline to little more than a trickle. In 2011 though this area was in the midst of a severe drought. There was little snow the previous winter and very few spring and summer rains. The intense rains of late July and August that can produce short lived flash floods on Turkey Creek did not come in 2011. Throughout most of the summer, surrounding vegetation was in poor condition and many plants showed severe moisture stress. Interestingly, the woody vegetation on the upper portions of the east bank of the spill area exhibited only minor moisture stress. Apparently, the slide debris that forms a bench on the east side of the stream, is a deep reservoir of moisture that supports plant growth even in drought. This also explains why, shortly after the east bank rehabilitation was completed, woody plants that had been damaged showed strong regrowth with little evidence of moisture stress. The overall configuration of the stream rehabilitation was directed at re- establishing the original channel in its pre -spill condition. However, it is now evident that the pre -spill alignment is not the most stable alignment for the stream. It is the stable alignment for the stream in the post - landslide condition, but it is not the natural alignment that was established before the landslide. That alignment involved a much broader curve with less elevation drop per unit of horizontal distance and further to the west against the 30 foot rock wall that backs the bench. That is the alignment the stream should actually have and the presence of the slide debris explains the unusually steep grade of the stream channel in its post - landslide alignment. It was decided not to put the stream back into that pre - landslide alignment, even though that is clearly the best alignment. Doing that would create an abrupt, major change in the stream alignment Menzer Quarry Corrective Action Amendment Exhibit E October 2011 Page 3