Chevron Mining, Inc.
Highwall Slope Stability
AAI has investigated various aspects of highwall stability at several pits at the Kemmerer Mine, including large-scale slope failure, wedge analysis, and most recently, rockfall risk assessment. Alternative catch bench and berm designs were evaluated using the statistical CRSP program and numerical UDEC models. Both programs were calibrated using on-site experimental measurements.
Highwall Mining Evaluation
A comprehensive evaluation was completed of the geotechnical and operational issues related to conducting highwall mining in three different pits. The combination of multiple thick, steeply dipping seams and variable topography resulted in a challenging optimization study balancing recovery, practicality (cost), and safety. Candidate mining configurations involved varying the opening inclination and mining height (multiple passes) and using multiple lifts. Several empirical design techniques were employed in addition to a number of numerical models to develop pillar design charts for the optimum opening configuration. The weakening effect of the highwall mining openings on overall slope stability was also analyzed.
