Developed the hydrogeologic conceptual and numerical flow models for Diavik, an Arctic mine. Modeling included calibration to head data, gallery inflow data, tracer test data, and shut-in test data. The mine is located within a geologically-complex terrain comprised of volcanics and faulted granitic and metasedimentary deposits. An existing geologic/structural model was used as the basis for the numerical flow model. The calibrated flow model was used to represent alternate interpretations of faults, and predict future inflow rates at lower mine levels. Initial predicted results from the post-calibration period using newly acquired data indicate that the model has been successful at predicting heads and head response to dewatering at depths hundreds of meters deeper than the depths from which calibration data were available. Project included development of new methodology for spatial analysis and representation of the hydrogeologic interpretation coupled with the geologic/structural interpretation. The model was further discretized for application of slope stability analyses. Predictive modeling will allow for dewatering design through the mine life. Project included beta testing of new inverse method.
Analyzed current data and re-calibrated a flow model for multiple mine sites in Nevada and California. Data analysis activities included assessment of dewatering effects from exploration drilling, interpretation of recharge based upon mine surface features, and the incorporation of a pitlake package to simulate the hydraulic behavior of the ground water/surface water system in the vicinity of the pits. Data preparation and grid modifications included development of Fortran programs.
Selected and implemented a suite of analytical solutions to simulate pit dewatering during mining and pitlake recovery under two proposed closure alternatives for a mining site under permit review in California.
Performed hydraulic testing and analysis at the Newmont Deep Star site near Carlin, Nevada. Conducted packer testing to evaluate the permeability of a faulted and fractured formation associated with the ore zone for feasibility analysis of the hydrologic component of underground development. This feasibility analysis supported development of the first underground mine along the Carlin Trend.
Formulated work plan for quantification of river leakage impacting inflow rates at an underground mine. Rock types include limestone, shale and crystalline basement, the latter of which has been folded and faulted creating a structurally complex flow system.
Performed the hydrogeologic and geotechnical evaluations for a future tailings site at a Newmont mine in NV.
Project hydrogeologist for water supply well sites at a Newmont mine in NV.
Designed pump system for high inflow rates for a copper mine in Zambia.
Revised and re-calibrated the numerical model for use as a water-management tool for a Battle Mountain Gold mine site in Nevada.
Participated in mineral resource evaluation of coalbed methane deposits in China. Responsibilities included fracture analysis, and selection and oversight of various testing procedures to determine confining pressures and stress fields contemporaneous with gas formation; and rank of the coal throughout the field (by ASTM methods).
Participated in numerous hydrogeologic characterizations to support mine permitting for proposed mines and mine expansions in Colorado, Montana, Utah, Nevada, Oregon, California and Northwest Territories.
Designed and implemented pilot-scale pumping tests for tailings dewatering at the Atlas Uranium Mill Tailings Site in Moab, Utah as part of the Correction Action Plan.