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the asphalt plant is sedimentary, consisting of shales and sandstones <br />upturned to near vertical orientations, striking almost north-south. The <br />asphalt plant has been upgraded with significant structural and foundation <br />work being completed in the past two years. The highwall located <br />immediately west and north of the bottom plant facility is currently stable, <br />with no evidence of significant highwall instabilities (Photo 10). Several <br />localized water seeps were noted in alternating beds along the exposure of <br />the sedimentary unit but did not appear to be impacting stability. No other <br />significant changes in the condition of the highwall were noted and no major <br />cracks, settlement, or ponding areas were identified in the ground surface <br />above the highwall, leading us to conclude that the asphalt plant highwall is <br />stable under the current conditions. <br />Between the highwall and portions of the new facility a new concrete <br />masonry retaining structure has been installed at the base of the highwall. <br />' The structure is approximately 100 feet long by 20 feet high by 20 feet wide, <br />and is reinforced and backfilled with graded crushed aggregate. It is L&A's <br />understanding that this structure has been installed in order to further <br />stabilize conditions along the highwall and to protect the recent upgrades to <br />~ the plant (Photo 11). <br />In addition to the inspection of the highwall, observations along the access <br />road leading from the lower part of the asphalt plant to the top were also <br />made with no surface cracks or settlement noted. Some minor erosion was <br />identified, but is not currently impacting the stability of the access road. <br />Monitoring of this area should continue. The road is located perpendicular <br />to the strike of the bedding, which is a favorable orientation for minimizing <br />slope stability problems along the access road (Photo 12). <br />-11- <br />