The 250-ton slab of Navajo Sandstone peeling off the south wall of the canyon at Glen Canyon dam has been bolted into place to prevent it from falling on to power plant facilities immediately below (bottom photo). The photo below shows the slab in the lower left area of the circle below with dozens of dark circles marking the rock bolts. [my photo, 10-5-15]
An official at the dam said plans are to remove small pieces of the slab over time to eliminate the threat.
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