REP23690 - Laserfiche WebLink

Home Browse Search

' IV. GEOTECHNICAL DATA COLLECTION SUMMARY ' 4.01 General ' During 1999, no special detailed geotechnical data collection was necessary for either localized failure areas or highwalls excavated at slope angles steeper than default slope angles. General observations were made in the active mining areas in the Central Quarry, ' and in the North Quarry, but no detailed data collection was required or performed for interim slopes [here, in accordance with permit conditions. Geologic mapping of new final highwalls was performed at Bench A and B highwalls of the east and west sides of the Central Quarry. In addition, the optical survey of surface survey monitor points in and around the repaired failure area in the east side of the Central Quarry ' continued in 1999. During 1949, excavation in the Central and the North Quarries did not exceed any conditions ' that would require reevaluation of stability of the cut slopes. Mining in the Central Quarry was limited to excavation of benches at leas[ 30 ft wide and highwalls 50 ft high or less on the east and west sides. Within the North Quarry, 40 ft highwalls and 40 to 50 ft benches were established, not exceeding an overall slope configuration of 1 H:1 V. ' 4.02 East Side of the Central Quarry ' A. Geologic Mapping Geologic mapping data was collected far Bench A and Bench B at the east side of the Central Quarry. Joint orientation (strike and dip) data was measured at approximately 100 f[ intervals or areas of strucmral interest for final highwall segments established during 1999. Other mapping data and observations such as ' fault/shear zone locations, fold axis trends, and intrusive dike locations, as well as notes about rock type and condition, were documented. This information is included on the topographic map included as Plate 1 in Appendix A. ' B O ti l S . p ca urvey CAMAS provided survey support of the investigation and repair of the localized ' failure in the east side during 1996. Survey support continued during 1999 in the form of continued monitoring of the post-repair surface settlement points via optical survey. Survey data for March 1997, May 1997, March 1998, October 1998, and ' August 1999 document the perforntance of the repair during 1997. A discussion of these data is provided in Section 5.02. and the data are included as Appendix B. 4.03 West Side of the Central Quarry ' Geologic mapping data was collected for Bench A and Bench B at the west side of the Central Quarry. Joint orientation (strike and dip) data was measured at approximately 100 f[ intervals or areas of structural interest for final highwall segments established during 1999. Other mapping data and observations such as ' fault/shear zone locations, fold axis trends, and intrusive dike locations, as well as a Q1FRUlF,CTS'u~~2fA Mornron QwurtWS4997tneu(NWUUrkup.drc