Our team
Dr. Liz Andrews is a hydrogeochemist with extensive experience in geochemical measurements and hydrogeochemical data interpretation. Legacy Geosciences is Liz's first venture into mining consulting. Prior to joining Legacy, she managed geochemical facilities and instrumentation for elemental and isotopic analysis of earth materials. Her academic research focused on simulating mineral precipitation and dissolution in fractured rocks using reactive transport and hydrologic models. With expertise in geochemical analysis and numerical simulations, Liz will support hydrologic and geochemical investigations using PFLOTRAN and PHREEQ-C.
Dr. Alan Jang is a hydrogeologic modeler with more than 20 years of experience in groundwater flow and contaminant transport modeling, subsurface investigations, and numerical code development. His work focuses on mining hydrogeology, including mine permitting, operational water management, and closure planning. Dr. Jang has extensive experience developing and applying numerical groundwater models to support mine dewatering design, water balance evaluations, and environmental impact assessments. He has worked on mining projects across the United States, South America, South Africa, and India, addressing complex hydrogeologic systems associated with open-pit and underground mining operations. His technical expertise includes analytical and numerical analyses of single- and multiphase subsurface flow, reactive chemical transport in saturated and unsaturated media, non-aqueous phase liquid migration, and density-driven groundwater flow. Through his modeling work, Dr. Jang supports mining companies and regulators by providing defensible technical analyses for permitting, operational planning, and long-term mine closure strategies.
Gary Johnson is a mining focused hydrogeologist with 8 years of experience in consulting for the mining and 3D modeling industries. Gary is a global expert in Seequent's Leapfrog Geologic Modeling software, which is used extensively in the mining industry to build resource and conceptual 3D models. Gary also has extensive experience in groundwater modeling and conducting field work at various mine sites, both domestically and internationally. He has constructed groundwater flow models for mine sites in the United States, South America, and Africa, supporting baseline studies, environmental impact assessments, mine dewatering for open-pit and underground operations, and mine-closure planning. He has also planned and participated in various hydrogeologic and geotechnical field studies around the world. Gary brings a unique skillset to the project team with his ability to create 3D visualizations that bring your site to life.
Dr. Houmao Liu has more than 30 years of project experience in mining hydrogeology, geochemistry, and groundwater flow modeling. He has worked on and directed numerous mining hydrogeology projects in southern Africa, South America, Turkey, North America, Europe, Russia, and East Asia. He has also been the Principal-in-Charge of ITASCA's hydrogeologic projects for key mining companies, such as Rio Tinto, De Beers, Cameco, Anglo American, Debswana, Doe Run, Newmont/Goldcorp, Alrosa, Hecla, Vale, Freeport-McMoRan, and Codelco. These projects include mine dewatering, slope depressurization, water management of surface and underground mines, environmental impacts, and mine water quality. In addition, Dr. Liu has extensive experience in the code development of MINEDW as well as more than 25 years of groundwater flow modeling experience using other commercial codes, such as MODFLOW, MT3D, and FEFLOW. He has taught mining hydrogeology short courses at the Society for Mining, Metallurgy & Exploration (SME), Cameco, and the American Rock Mechanics Association (ARMA). He also provides expert opinions for regulatory hearings and due diligence reviews. In addition to his project experience, he also taught the hydrogeologic section of several caving short courses.
Dr. Steve Meyerhoff was the project manager and groundwater modeler for the Goldrush and Fourmile, Phoenix, Twin Creeks, and South Area Operations projects as well as other modeling projects in Nevada. Dr. Meyerhoff is also an expert in conceptual and numerical model development for mining hydrogeology projects. Dr. Meyerhoff has conducted more than 30 numerical groundwater flow modeling studies for large-scale open-pit and underground mines in Nevada, Arizona, Canada, Europe, South America, and Africa. His project experience includes the development of hydrogeologic conceptual models, construction and calibration of groundwater flow models, construction and calibration of solute fate and transport models, management of projects, and preparation of technical reports. The results of the groundwater models he has developed have been used to design dewatering and water-disposal systems, as inputs for slope-stability analyses, for water-management studies, and for international, federal, and state permitting studies (i.e., EIS, EAs, DNAs, and WPCPs).
Dr. Bryan Moravec has more than 20 years of project experience in mining hydrogeology and geochemistry and is an expert in materials characterization and baseline assessments for pre-feasibility/feasibility and permitting new and mine expansion projects. He has worked at several base-metal, precious-metal, and oil-sands mines, focusing on acid rock drainage characterization and predictions, metals mobilization and attenuation, weathering processes, mineral surface geochemistry, and water quality investigations. He specializes in pre-feasibility, feasibility, operational, and closure geochemistry to meet permitting requirements and closure designs, as well as operational geochemical investigations to mitigate water impacts in support of effective mine water management. Dr. Moravec has designed and executed several fit-for-purpose projects, from small-scale, standalone geochemical studies to complex site-wide characterization projects.
Benjamin Radtke is a hydrogeologist with 8 years of experience in consulting for the mining industry, providing a data driven approach to evaluating and managing water-related risks. His project repertoire covers PFS/FS, permitting, operational, and closure stages for multiple commodities across the globe. Ben has extensive experience in designing and managing hydrogeologic field programs, as well as conducting hydrogeologic data analysis and conceptual groundwater model development for site hydrogeologic characterization purposes. He also has experience in developing numerical groundwater flow and solute transport models for simulating site hydrogeologic conditions, life of mine, and closure predictions.
Mr. Andrew Whittle has over 6 years of consulting project experience in the mining hydrogeology industry. He attained his masters in Hydrologic Science and Engineering from Colorado School of Mines. Mr. Whittle specializes in everything from the initial planning to technical report writing of mining hydrogeologic programs. He has extensive experience in field data collection programs on a variety of drilling rigs such as packer testing, vibrating wire piezometer installation and datalogger setup, well installation and development, constant and falling pumping head tests, core logging, geochemical sampling, etc. Regularly tasked with the management and analyzation of data gathered in the field as well as technical report writing. The results of these hydrogeologic testing programs have been used to assess the feasibility of numerous mining and dewatering programs across Nevada.
Jianwei Xiang, Ph.D., is a Senior Hydrogeologist with over 15 years of specialized experience in numerical modeling for the global mining industry. He holds a Ph.D. in Hydrology and Water Resources from the University of Arizona and has built a distinguished career focusing on groundwater inflow prediction, open-pit depressurization optimization, and pore-pressure modeling for slope stability. His project portfolio spans six continents, including major diamond, copper, and gold operations in Botswana, Chile, Canada, and the USA. In addition to his field expertise, Dr. Xiang is a skilled programmer in C++, Python, and C#, contributing to the development of groundwater modeling software and advanced solute transport simulations.