PERMFILE118982

• Permit No: M1997014
• IBM Index Class Name: Permit File
• Doc Date: 2/25/1997
• Section_Exhibit Name: PERMIT FILE
• Media Type: D
• Archive: No

on the North end of the wall which terminates in quarry floor, thus
eliminating a potential failure plane. It appears that good quarry safety
design dictated that this approach be utilized to maintain the stable slope
(Figure 6e). Strikes and dips taken here: 322 degrees with a dip of 44
degrees to the Southwest, and 360 degrees with a dip of 70 degrees to the
East.
The West wall has a fracture spacing from 6 to 8 inches and has a number
of subparallel joints relatively closely spaced, i.e., less than one foot, dipping
into the quarry. A small planar joint surface can be seen near the south
end of the West wall which was probably removed for safety reasons. The
orientation of the joint plane strikes at 275 degrees with a dip of 46 degrees
to the Northeast. Figure 7 shows subsequent ravelling of material into the
quarry and on to the safety bench in the area of this planar feature.
The West wall bedrock surface consists of excavations and rock removed
predominantly along existing joint planes which dip into the quarry. Many
of the dips on the surficial joint surfaces appear to be part and parcel of the
same joint set. There is a resulting sloping "stair-step" effect which shows
up in the photos taken of this wall (Figure 8). As can be seen, while joint
faces control the slope of the rock face, the backside of the joint face is
typically blasted. The West wall has an overall orientation of 105 degrees
with a dip of 52 degrees to the Northeast. At the North end of the West
wall, there appears to be several boulders in excess of one foot in diameter
resting on a mixed rock rubble and soil slope which is revegetated with
grass. The soil slope near the West wall dips on the average of 45
degrees.
Bench 2. The second bench is defined by being approximately 50 feet higher than the
first bench and consists of a "U" shaped excavation with rock outcrops seen
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