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Highwall Measurements of the slope of [he highwall were taken from vantage points severi distant by various members of the group using a BruntonT*' Compass. The slope of tlt measured in the following values, 48, 68, 46, 60, 59, and 60 degrees from horizontal. average of the slopes is approximately 57 degrees. The large vaziation in slope angl to different vantage points and the roughness of the slope. hundred feet e highwall was The azithmetic ;s is likely due The highwall was constructed with three benches, is approximately 110 feet high, and is located approximately 140 feet from Colorado State Highway 141. The highway is protec ed from rocks falling off the highwall and rolling toward the highway by berms constructed near a highway as visual and protective barriers. The major jointing orientation appears to be perpendic laz to the face of the highwall as is indicated by the pegmatite dike and other intrusions intruded alo fractures and planes of weakness shown on the attached photographs. The highwall was cleaned (reported by Mr. Schmall) of loose rocks by hand scaling ~he slope. Six men with pry bars worked to remove rocks from the slopes and benches. The rocks they removed did not roll to the highway and they removed a significant rockfall hazazd. The report by Agapito Assocjates, Ina(AAI), prepared June 19, 1987 recommended a~benched slope with an overall finished slope of 53 degrees for stability. They also concluded that t e jointing and fracture patterns did not adversely affect the stability of the highwall. Given that the highwall slope is close to that recommended by AAI and that our obs rvations were that the main jointing is perpendicular to the face, we feel that the slope is reasonab y stable. We recommend that if consideration of the highwall can be separated from the stock ile, [he Staff consider approving the highwall as it presently exists with one stipluation. The sti lation would require construction of another berm to "close" the access road as a route for rolling ocks to enter the highway. Removal of the 60,000 Cubic Yard Stockpile Removal of the stockpile was discussed at the meeting. Mr. Erickson brought up the possibility of selling the stockpile material to CDOT. The discussion resulted in Mesa County indi sting that the county would not have a problem with this alternative. CDOT personnel indicated that the rock appeared to be useable, but could not commit for the operations personnel. It is the Division's feeling that if the material can be sold and the slope revegetated th would be in the best interest of all parties. The resolution of the meeting was that Mr. Schmall w uld approach CDOT with the question and report back. Summary In Summary, it is the Division of Minerals and Geology's recommendation that the hi hwall be left in place, and protected by a berm. We recommend [hat [he 60,000 cubic yard stockpil be removed down to the original soil, the soil tested to see if it requires augmentation prior to re-se ing, and the