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gre senior associates

mark smith, pe, ge, dgE, se

expert geotechnical engineer

Mr. Smith has been working in heap leaching since 1979 and focused on Heap Leach / SX-EW projects for gold, silver, copper, nickel, and uranium since 1979. He has worked extensively throughout the Americas, Africa, and Asia; his key clients include BHP Billiton, Rio Tinto, Vale, Xstrata, Anglo American, Barrick, Codelco, Groupo Mexico, Glencore, Minmetals, Newmont, Freeport, and many mid-tier companies. He has also worked extensively with the major EPCM firms: Fluor, Bechtel, Aker, Hatch, and SNC Lavalin. Mark is a registered civil, geotechnical, and structural engineer. He has published dozens of papers in the field and has taught engineering short courses through universities in 8 countries. He was the founding principal and manager of Vector Engineering, Inc., building it from inception to a team of 500 people working in offi ces in the USA, Australia, Argentina, Chile, Peru, the Philippines, and Colombia. Vector, now part of Ausenco, is a multi-disciplinary engineering and environmental consulting firm working for both local and multi-national clients.

dave hallman, pe, pg

expert geotechnical engineer

Mr. Hallman has more than 30 years of experience specializing in geotechnical engineering and construction on a variety of mining and civil engineering projects throughout the world. His technical expertise includes tailings and water dam design and construction, design and construction of heap leach and landfi ll facilities, static and dynamic stability of embankments an natural slopes, landslide evaluation, rock slope stability, open pit design, seismic risk characterization, liquefaction evaluations, dynamic deformation analyses, mine subsidence risk assessment and abatement, mine fi re investigation and extinguishment, liner and seepage cutoff system design and evaluation.

clay newton


Mr. Newton is a certified professional geologist who has been responsible for project management, geological staff management, mineral reserve and resource evaluations, and planning and supervision of mine development programs. He has provided SEC and NI 43-101 compliant reserve and resource studies for gold, silver, base metals, coal, rare earth, and industrial minerals deposits. He has considerable experience in geological mapping, structural and tectonic surveys, geological and geotechnical core logging. He has designed Quality Assurance and Quality Control (QA/QC) procedures for gold and rare earth element exploration programs. He is experienced in ore deposit exploration with an emphasis on structural/tectonic and geochemical techniques. Mr. Newton is a Mining and Metallurgical Society of America (MMSA) Qualified Professional in Geology, Mining and Ore Reserves.

susan poos

senior mining engineer

Ms. Poos has over 25 years of experience in the mining industry predominately in open-pit mine planning and operations. Her experience includes working with precious and base metals, coal and industrial minerals in the Americas, Africa, Australia, Europe and Russia. Most recently she was Chief Mine Planning Engineer for Gold Fields Ltd. In this role, she worked with projects from preliminary evaluations of project potential through scoping, prefeasibility and feasibility studies as well as being involved in due diligence reviews. Throughout the project development process, Ms. Poos' focus was on strategic long-term planning for the Project and Corporation using tools such as Whittle and GEMS. Through her experience she has developed different ways of planning and evaluating projects based on management objectives whether these are maximize ounces or maximize margin. Her experience includes optimization analysis, mine design, production scheduling, resource and reserve estimation, cost estimation, permitting and financial analyses. Ms. Poos also has experience in management as a Vice President responsible for managing a consulting office and operationally as a Chief Mine Engineer. Ms. Poos fulfills the definition of a Qualified Person in accordance with Canadian NI 43-101, JORC and SAMREC standards.

Robert Hemming

mineral landman

Mr. Hemming has over 30 years of experience as a mining executive related to mineral land evaluation, development, acquisition, maintenance, and compliance. His experience covers mineral properties including precious metals, base metals, and uranium in North and Latin America. He has negotiated acquisitions of surface, mineral, and water rights and drafted several joint venture agreements. He has conducted the acquisition of public domain lands through mining claim location and concession denouncement to obtain federal and state leases and prospecting / exploration permits. Finally, he has coordinated the necessary permits, contracted environmental consultants and survey crews, and submitted plans of operations to insure compliance with federal and state natural resource laws and regulations.

gregory knell, cpg, chmm

environmental scientist

Mr. Knell is a certified professional geologist in six states and a certified hazardous materials manager with over 30 years of experience in hydrogeology, environmental assessment, waste management, and regulatory compliance. He has completed baseline environmental studies at mining properties as well as evaluation/assessment of environmental impact from mining operations. Mr. Knell has extensive field experience in the western U.S. and two Latin American Countries. He is well versed in surface water and groundwater monitoring network design, implementation, and evaluation; environmental permitting; the assessment and remediation of impacted groundwater and soils; waste characterization and identification of disposal options; and the preparation of SPCC and other critical material management plans.

james hitt,p.e.

senior mining engineer

Mr. Hitt is a registered Professional Engineer with over 40 years in the mining industry providing him with a thorough understanding of resource estimation, mine design, detailed planning, permitting, closure, and fi nancial analysis. He has extensive industry experience working in positions including the Director of Engineering, Engineering Manager, and Senior Mine Engineer for over 20 years before becoming a consultant. During his time in industry, he was responsible for construction management, engineering oversight, operations management, and new project acquisitions for multiple surface operations throughout the US. His core skills include project evaluation, due diligence reviews, mine design and planning, capital cost estimates, operating cost estimates, budget preparations, operations and engineering management, mine permitting, and closure. Mr. Hitt has worked both domestically and internationally with experience in India, Indonesia, Mexico, Columbia, Mongolia and Canada primarily in the coal, potash, and oil sands businesses.

benjamin juba

chief chemist

Mr. Juba is a Chemist with over 10 years of experience as an analyst and laboratory manager for several process-related companies. His analytical experience includes clients such as Great Western Inorganics, Inc, GeoSynFuels, LLC, Colorado Department of Agriculture, and Local Distilling Inc. He has worked as a laboratory manager and been involved in laboratory establishment, method development and trouble shooting.  He has experience with multiple analytical techniques including: ICP, AAS, GC, UV/VIS, XRF, YSI, FTIR, HPLC.  Mr. Juba has specialized in ICP analysis for organics and metals over the last several years and has also played an important role in product QA/QC.   Mr. Juba holds a B.Sc. in Chemistry from the Colorado School of Mines with an analytical emphasis and a M.Sc. in Engineering and Technology Management also from that same institution.

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