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Ángel Briseño Arellano
Hydrologist

Ángel Briseño Arellano

Hydrologist

MS, Hydrology and Water Resources
University of Arizona, 2018

BS, Geological Engineering
National Autonomous University of Mexico, 2013

Mr. Briseño is a hydrologist with experience in environmental and hydrologic studies since 2013. His work consists of performing physical and hydraulic property testing on large scale samples and laboratory data analysis, with a focus on investigating heap leach optimization. He also models surface and subsurface water-soil interactions, such as erosion, evaporation, and other unsaturated flow processes, specifically for mine waste cover systems. His field work involves soil, sediment, and water sampling in a wide range of investigations. In addition, he has instrumented various types of mining facilities for physical, hydrologic, and environmental monitoring. His background in geology and hydrology gives him a comprehensive basis to address a variety of issues in subsurface characterization.

  • Laboratory testing for physical and hydraulic properties in porous materials
  • Heap leach optimization
  • Analysis and modeling of saturated and unsaturated flow
  • Field testing of physical and hydraulic properties
  • Instrumentation and data collection systems
Layia Asakawa-Ekeland
Hydrogeologist

Layia Asakawa-Ekeland

Hydrogeologist

B.Sc. University of California
Santa Barbara; 2020

Ms. Asakawa-Ekeland assists in the lab with hydraulic property testing. She has work experience in geotechnical engineering and has spent over 200 days conducting field work in her studies and professional career. Her academic research experience includes geochronology, thin section petrochronology, and GIS. She has been primarily working on rapid brine release moisture retention curve testing, data analysis, and technical report writing for lithium brine samples from South America.

  • Laboratory testing for physical and hydraulic properties of porous materials
  • Physical characterization of soil and rock samples
  • Data management, compilation, and analysis
  • Quality Assurance/Quality Control
Monisha J. Banerjee, Ph.D.
Environmental Scientist

Monisha J. Banerjee, Ph.D.

Environmental Scientist

PhD, Soil, Water, and Environmental Science
University of Arizona, 2009

BS Biology
The George Washington University, 1998

Dr. Banerjee has been restoring and reclaiming disturbed habitat since 2007. Her work focuses on riparian restoration and abandoned agriculture and mined land reclamation, with significant expertise in arid/semi-arid land systems. She has been successfully managing complex restoration and monitoring projects to include monitoring soil moisture and groundwater, evapotranspiration cover system monitoring, site assessments for riparian restoration in saline affected areas, vegetation and erosion monitoring, and developing and implementing adaptive management strategies to meet restoration/ reclamation goals. Current projects responsibilities include designing databases for soil moisture and well monitoring data, site assessments to guide restoration planning, and mine cover system design and monitoring.

  • Mine cover system design and performance
  • Habitat restoration and revegetation studies
  • Vegetation, soil, and microbial analyses and survey techniques
  • Physical and hydraulic characterization of soils
  • Soil fertility and plant nutrition
Jaime Bañuelos
Hydrologist

Jaime Bañuelos

Hydrologist

MS, Soil Water and Environmental Science
University of Arizona, 2010

BS, Crop Production
University of Arizona, 2008

Mr. Bañuelos has been managing and supervising hydrology, soil science and crop production studies since 2011. He has managed multiple, large-scale, mine closure characterization and monitoring studies at mines in Perú and the USA and has extensive experience with physical and hydraulic characterization of soils for mine reclamation, groundwater recharge, and habitat restoration studies. His experiences ranges over a variety of environments from the arid southwest to wetter environments as those found in the Andes Mountains of Peru. He also has extensive experience in soil moisture, and soil salinity monitoring as well as soil and plant fertility assessments. Jaime is a fluent Spanish speaker.

  • Physical and hydraulic characterization of soils
  • Soil moisture and salinity management of arid lands
  • Soil fertility and plant nutrition
  • Mine cover system performance
  • Data analyses and management
Christian Barra
Soil Scientist

Christian Barra

Soil Scientist

MS, Environmental Science,
University of Arizona, 2024

BS, Forestry Sciences
University of Chile, 2011

Mr. Barra has eight years of experience in soil hydraulic, geochemical and agronomic property studies, soil-plant relationships and baseline environmental studies. Christian has expertise in field data collection, laboratory analyses, data interpretation and report writing. He has managed numerous studies in Chile, from the hyper-arid north of Chile to the subpolar maritime Tierra del Fuego, leading teams doing research on soil morphology, infiltration, heavy metal evaluations, soil moisture monitoring, vegetation monitoring, and environmental impacts to develop plans for compensation, restoration, and mitigation in degraded areas. In his research project for the MS at the University of Arizona, he assessed the effects of wildfires on the soil's biogeochemical and hydraulic properties to then model the main factors controlling the infiltration rates.

Nate Blevens
Environmental Scientist

Nate Blevens

Environmental Scientist

BS, Environmental Science
University of Arizona, 2013

Mr. Blevens has seven years experience as an Environmental Scientist with several years’ experience managing and conducting hydraulic property tests, geochemical and electrochemical analyses. He has significant experience in conducting heap leach optimization studies for a variety of mines around the world. His background in process improvement, lab management, and QA/QC allows for projects to be completed accurately and on time.

  • Laboratory testing for physical, chemical, and hydraulic properties in porous materials
  • Laboratory and project management
  • Heap leach optimization
  • Constructing instrumentation, custom lab equipment, and data collection systems
  • Quality Assurance/Quality Control
Lindsey A. Bunting
Environmental Scientist, Soil Scientist

Lindsey A. Bunting

Environmental Scientist, Soil Scientist

MS, Soil, Water and Environmental Science
University of Arizona, 2011

Environmental Science
University of Arizona, 2007

Lindsey Bunting has over 15 years of experience specializing in environmental monitoring, habitat restoration, groundwater recharge studies, mine reclamation and salinity management. She is skilled with soil field assessments, laboratory physical and hydraulic property testing, and data acquisition system management and troubleshooting. Lindsey manages large datasets from hundreds of soil, mine waste, groundwater, and surface water monitoring stations on a daily basis, and also provides expertise in soil biogeochemical cycling and nutrient dynamics in tropical ecosystems. She has served as the data manager for a large-scale soil and groundwater monitoring project to assist with adaptive management of habitat restoration sites along the Lower Colorado River. Currently, Lindsey is managing several long-term monitoring projects to support groundwater recharge projects and mine cover closure systems.

  • Managed aquifer recharge site screening investigations and monitoring
  • Habitat restoration and revegetation studies
  • Environmental monitoring system design, installation, maintenance, and management
  • Soil and groundwater field and laboratory analyses
Todd Caldwell
Senior Soil Scientist

Todd Caldwell

Senior Soil Scientist

Ph.D., Hydrogeology
University of Nevada, Reno, 2011

M.S., Hydrogeology
University of Nevada, Reno, 1999

B.S., Earth & Planetary Sciences
University of New Mexico, 1997

Todd Caldwell has over 25 years of experience in monitoring, characterizing, and modeling unsaturated zone processes. His work focuses on in-situ and remotely sensed monitoring systems applied to mine tailings and waste cover systems. Recent responsibilities include developing national soil moisture monitoring protocols and a framework to assess mine closure covers at Uranium Mill Tailing Facilities.

  • Waste cover system design and evaluation
  • Numerical modeling, parameter optimization and uncertainty analysis
  • Environmental monitoring systems and instrumentation for vadose and saturated zones
  • Disturbed soils and arid land restoration
  • Groundwater recharge and evapotranspiration
  • Geophysical techniques for subsurface characterization
Todd Caplan
Restoration Program Director, Senior Vegetation Ecologist

Todd Caplan

Restoration Program Director, Senior Vegetation Ecologist

M.S. Natural Resources Conservation
University of Montana, 1996

Todd Caplan is a senior ecologist with GSA. He has been working nearly 30 years integrating scientific disciplines of vegetation ecology, soil science and hydrology in the design, implementation, monitoring and adaptive management of large-scale river and arid-land restoration programs. Prior to working as a consultant, Todd served as the Natural Resources Director for a 37,000-ha American Indian reservation where he initiated and managed grant funded watershed restoration programs. Since 2002, he has worked as a consultant to support federal, tribal, state and private sector clients with addressing complex watershed management and restoration challenges. His work has included burned area rehabilitation on wildlife refuges in Arizona and New Mexico, developing tropical forest restoration monitoring programs in Papua New Guinea, and leading development of large-scale floodplain habitat restoration designs across the Southwestern US.

  • Natural Resources Management & Planning
  • Monitoring and Adaptive Management
  • Arid Land and Floodplain Ecosystem Restoration
  • Riparian Ecology
  • Exotic Plant Management
  • Revegetation/Bioengineering
  • Restoration Construction Oversight
  • Grant Writing
Brennan Davis
Ecologist/GIS Analyst

Brennan Davis

Ecologist/GIS Analyst

Brennan is an ecologist and GIS analyst with over 10 years of experience working in New Mexico. His experience ranges from public land management and planning to hydrological and botanical surveys, as well as GIS and remote sensing analyses. He seeks to integrate on the ground data collection with remote sensing approaches to develop a comprehensive understanding of ecosystem form and function. From regional-scale studies to site-specific projects, Brennan’s integrated approach helps to develop creative solutions to complex questions. He is excited to continue his growth as an ecologist and GIS analyst with GSA, offering data-driven, actionable results for clients.

Nathan Haws, PhD, PE
Principal Engineer

Nathan Haws, PhD, PE

Principal Engineer

PhD, Civil and Environmental Engineering
Purdue University, 2003

MS, Civil and Environmental Engineering
Brigham Young University, 1999

BS, Civil and Environmental Engineering
Brigham Young University, 1999

Nathan Haws is a registered professional civil engineer with over 15 years of engineering experience focused on surface and near surface water management, particularly for the gold and copper mining industry. He has served as project technical lead of the analysis and design of surface mine reclamation; mine heap leach facilities; river stabilization; and surface water risk mitigation in diverse regulatory and climatic environments. Nathan has authored or co-authored several peer reviewed publications and conference papers related to water and solute transport, surface water erosion protection, and heap leach design.

  • Surface water hydrology
  • Vadose zone hydrology
  • Open Channel hydraulics
  • Mine drainage master planning
  • Riverbank and levee stabilization
  • Stormwater management
  • Mine reclamation and closure
  • Heap leach design
Quentin R. Hays
Senior Wildlife Ecologist

Quentin R. Hays

Senior Wildlife Ecologist

M.Sc., Biology, Ecology and Evolution
University of Western Ontario, 2008

B.S., Wildlife Biology, Honors
University of Montana, 2001

Quentin Hays has nearly 20 years of experience as a professional wildlife biologist, including extensive work within the private sector and academia as well as with government agencies and non-profit organizations. His research background and expertise centers on avian ecology and mammalogy, and he has spent much of the past decade focusing on the interaction of wildlife and utility-scale alternative energy facilities. In addition to managing large-scale energy projects, Quentin has managed complex electrical transmission development projects in the Southwest and has provided wildlife-centered consultative support on a number of mining projects. Quentin has also worked extensively with the USDA Forest Service developing survey and management strategies for sensitive wildlife species, conducting post-wildfire monitoring and forest restoration, and continues to work with American Indian tribes in the Southwest to support wildlife resource management.

  • Avian Ecology
  • Biology and Ecology of Bats
  • Interaction of Wildlife and Energy Infrastructure
  • Threatened, Endangered, and Sensitive Species Monitoring and Mitigation Planning
  • Ecological Monitoring Design, Implementation and Trainin
  • Fire Ecology, Post-fire Monitoring and Restoration
  • Southwest Forest Restoration
  • Grant Writing
Quinn Hull
Staff Hydrogeologist

Quinn Hull

Hydrogeologist

MS, Hydrology
University of Arizona, 2022

BS, Geology
Oberlin College, 2014

Quinn has 10 years of experience as a water scientist specializing in the simulation and analysis of hydrologic systems. He has led interdisciplinary multi-year monitoring campaigns of contaminated groundwater; built and installed sampling systems at the groundwater/surface-water interface in rivers and lakes; and created and managed database systems for tabular and geo-spatial hydrologic datasets. Prior to joining GSA, Quinn worked in government, NGO, and academic settings. Quinn's integrated field and computational experience helps add to GeoSystem's data analysis capabilities.

  • Analysis and modeling of saturated and unsaturated flow
  • Relational database management systems
  • Machine learning and data analysis
  • Field and lab testing of hydrogeochemical, physical and hydraulic properties
Kai Jones
Hydrogeologist

Kai Jones

Hydrogeologist

Kai is a recent University of Arizona graduate and is new to the field of hydrogeology. With their new degree, they are interested in learning the specifics of soil properties and are excited to gain valuable experience in all areas of the field. Kai performs sample testing and data collection in the laboratory.

Jason Keller
Senior Hydrogeologist

Jason Keller

Senior Hydrogeologist

M.S. Soil, Water, Environmental Science
The University of Arizona, 2002

BS, Environmental Science
Oregon State University, 1998

Registered Geologist
Oregon and Arizona

Mr. Keller has over 20 years of experience performing subsurface assessment and modeling studies, including the design and implementation of site-characterization investigations. His work focuses on investigating groundwater and vadose zone processes using field, laboratory, and numerical tools. Mr. Keller’s work includes material characterization, monitoring, and unsaturated and saturated flow modeling to investigate groundwater recharge at diverse locations ranging from the Pacific Northwest, Great Basin, Rocky Mountains and southwestern deserts in the United States to the Andean Mountains and deserts of South America. Mr. Keller has performed water balance studies at small catchment scales and basin scales in excess of 200 square miles. Additionally, Mr. Keller has applied his expertise in unsaturated zone hydrology to evaluate subsurface impacts of waste management areas, performance of waste cover systems, heap leach hydrodynamics and soil erosion.

  • Saturated and unsaturated flow
  • Subsurface characterization
  • Water balance numerical modeling
  • Groundwater recharge processes
  • Surface water / groundwater interaction
  • Waste cover system design and performance
  • Heap leach hydrology optimization
Jacquelyn Kellin
Wildlife Ecologist

Jacquelyn Kellin

Wildlife Ecologist

Jacquelyn has a B.S. in Biology with a Concentration in Ecology, Evolution, and Organismal Biology from The University of New Mexico. During undergrad, she worked as an ecology research assistant to record and map observations of threatened, endangered, and sensitive species in New Mexico. Since receiving her bachelor’s degree, she has participated in various types of field work in the southwest for avian, small mammal, fish, amphibian, and plant species. She currently focuses on coordinating and participating in field surveys to monitor avian species with an emphasis on nesting and/or threatened, endangered, and sensitive species.

Laurel J. Lacher
Senior Hydrogeologist

Laurel J. Lacher

Senior Hydrologist

PhD - 18 years experience

Dr. Lacher has over 20 years experience on surface water and groundwater investigations, modeling and monitoring, and in water resources development, management, and watershed protection. Dr. Lacher created, and continues to consult to the Hydrology and Water Resources Program for the 1.7-million acre Fort Apache Indian Reservation. Accomplishments include establishing water quantity and quality monitoring programs, evaluating and expanding the Tribe's water supply and developing natural resources policy. Other experience includes the design, installation, and testing of municipal water supply wells, and groundwater flow modeling to support Endangered Species Act assessments and groundwater recharge impact analysese. Dr. Lacher also serves as an expert witness on stream-aquifer interactions and drought impact analysis.

  • Groundwater resource development
  • Water resources evaluation and planning
  • Wildfire damage assessment and stabilization planning
  • Source water assessment and watershed protection
  • Numerical modeling of groundwater and surface water systems
Jeff Ladderud
Hydrologist

Jeff Ladderud

Hydrologist

MS, Hydrology
Colorado School of Mines, 2014

BS, Geology
Washington State University, 2013

Jeff Ladderud has over 5 years of experience in environmental studies focused on mine waste mitigation and closure. He specializes in conducting and supervising hydrogeologic field and laboratory investigations. He has conducted field studies evaluating dust control measures on mine sites in a variety of climates in the western USA, as well as surface water sampling campaigns in the Colorado Rockies. Jeff has run laboratory and pilot-scale studies of sulfate-reducing bioreactors for the passive remediation of mine-influenced waters. Recently, Jeff has assisted in the maintenance of automated groundwater and vadose zone monitoring systems.

  • Hydrogeologic and environmental field investigations
  • Fugitive dust management
  • Mining geochemistry
  • Environmental monitoring system maintenance
  • Data processing and analysis
Chad McKenna
Ecologist, GIS Analyst

Chad McKenna

Ecologist, GIS Analyst

BS. Biology
University of New Mexico, 2001

Chad McKenna is an ecologist and GIS analyst with more than 12 years of experience performing vegetation inventories, designing and implementing large-scale floodplain restoration projects, and designing and developing GIS databases. Over the past ten years, he has served as the lead rangeland specialist and data analyst on rangeland assessments over more than 3 million acres of tribal land in NM and AZ. He has also mapped riparian and wetland vegetation along nearly 250 river miles of the Rio Grande to support various river and floodplain restoration projects. Chad provides tremendous value to our clients by his ability to integrate his field experience with comprehensive geo-spatial and tabular data analysis capabilities.

  • Geographic Information Systems
  • Ecological data management and analysis
  • Vegetation mapping and plant community studies
  • Noxious weed inventory and management
  • Riparian and wetland restoration
  • Rangeland stocking rate studies
  • Certified Rangeland Specialist, Certified Wetland Delineation, Member of the NM Noxious Weed Advisory Committee
Michael A. Milczarek
Program Director, Senior Soil Scientist

Michael A. Milczarek

Program Director, Senior Soil Scientist

MS, Soil and Water Science
University of Arizona, 1994

BS, Chemistry and Environmental Science
Northern Arizona University, 1984

Mr. Milczarek has over 25 years of experience with the development, implementation, and management of hydrogeologic and geochemical studies. He has a broad range of project management experience on groundwater recharge studies, mine waste cover system design, riparian habitat restoration and monitoring, monitoring of natural groundwater recharge in a variety of environments, and heap leach hydrodynamic studies. Mr. Milczarek has also designed and conducted professional workshops on groundwater recharge, mine waste cover systems and heap leach optimization. He has authored or co-authored over 40 refereed publications on groundwater recharge, vadose zone characterization and modeling, mine reclamation and habitat restoration.

  • Groundwater recharge processes
  • Mine waste closure system assessment and design
  • Habitat restoration
  • Unsaturated flow and contaminant fate and transport
  • Surface water/groundwater interactions
Kurt Minno
Laboratory and Field Technician

Kurt Minno

Laboratory and Field Technician

Mr. Minno assists in the research, design, and implementation of monitoring systems and laboratory testing as GSA's hydrologic technician and lab field specialist. Kurt specializes in design and fabrication of custom equipment for hydrologic flow rate testing, as well as installation, maintenance and repair of a diverse array of field instrumentation. In the lab, Kurt ensures viable and consistent data collection, examines and interprets data, and improves testing efficiency and laboratory processes. Kurt, began working as a metallurgical technician in 2016, and transitioned to hydrology in 2020. He ensures the laboratory provides viable, reproduceable, and high quality data for hydrological analysis.

Iozsef Miskolczi
Principal Engineer

Iozsef Miskolczi

Principal Engineer

MASc, Mining and the Environment
University of British Columbia, Vancouver, Canada, 2007

Dipl. Ing. Underground Mining Engineering
Universitatea de Nord, Baia Mare, Romania, 1999

Iozsef is a Professional Engineer who has over 20 years of experience in the mining industry with proven expertise in a multidisciplinary approach to mine waste management and mine closure. He has worked his entire life in and around mines, working his way up from laborer to Principal Engineer, which allows him a unique perspective and deep understanding of the mining process. He joined GSA in 2023 and is based in Vancouver, Canada. He is familiar with all stages of project planning, from PEA through permitting and into operations. He has completed mine reclamation planning and mine waste facilities design studies and is familiar with GISTM, environmental guidelines and regulations, and regulatory requirements. His expertise is in soil covers design, performance prediction, and performance monitoring as well as geotechnical design and materials characterization of cover soils. He has completed numerous projects including numerical modelling of unsaturated flow to predict performance of proposed cover configurations, as well as supervising installation of instruments and commissioning of data acquisition systems, followed by data management and data interpretation.

  • Mine reclamation planning, design, and performance
  • Cover designs
  • Unsaturated flow studies
  • Numerical modeling
  • Environmental monitoring systems and instrumentation
Rebecca Moskal
Hydrologist

Rebecca Moskal

Hydrologist

Rebecca has a bachelor's degree in geology from Eastern Kentucky University and a master’s degree in hydrology from New Mexico Institute of Mining and Technology. During her undergraduate degree she worked on a project studying ridgetop aquifers in Kentucky using electrical resistivity tomography. In her master’s degree she had a project that focused on flash flood events in a local arroyo that was monitored using aerial photography and HEC-RAS modeling to estimate sediment deposition and transport.


Haley Ormsbee
Civil Engineer

Haley Ormsbee

Civil Engineer

Haley is a recent MS graduate with 2 years of experience in surface water modeling. Her recent work has focused on one- and two- dimensional modeling to support silvery minnow habitat restoration along the Middle Rio Grande. She has experience using a wide range of modeling softwares including HEC-RAS, HEC-HMS, HYDRUS, BehavePLUS, Forest Vegetation Simulator (FVS), and GoldSim. In addition, Haley has experience in conducting hydraulic property laboratory tests. She has also assisted in a variety of projects including post-wildfire flooding, drainage management, and irrigation structure design.

Bob Rice
Senior Soil Scientist

Bob Rice

Senior Soil Scientist

MS, Civil Engineering
Arizona State University, 1965

BS, Agricultural Engineering
Colorado State University, 1960

Mr. Rice has over 40 years experience on developing methods for measuring hydraulic conductivity of soils, aquifer material and groundwater recharge. The field methods he helped develop are accepted by government agencies, engineers, and scientists throughout the world. In addition, he has extensive experience in wastewater renovation by soil-aquifer treatment. He has also conducted research on spatial variability of solute transport and preferential flow phenomenon in the vadose zone as part of best management practice studies related to irrigation and fertilizer applications. He has conducted numerous groundwater recharge investigations and is the author or coauthor of 75 publications.

  • Measurement of soil and aquifer hydraulic properties
  • Soil-aquifer treatment of waste water
  • Groundwater recharge investigations
  • Transport of water and chemicals through the vadose zone and groundwater
  • Vadose zone instrumentation and experimental design
Gabriel Rogers
Hydrogeology Laboratory Technician

Gabriel Rogers

Hydrogeology Laboratory Technician

BS, Environmental Health
University of Arizona 2019

Mr. Rogers has six years of a combination of analytical and process-based lab work experience, with experience in various geotechnical testing techniques and soil properties.

Justin Showalter
Environmental Scientist I

JustinShowalter

Environmental Scientist I

BS, Environmental Science
University of Arizona, 2023

Justin holds an environmental science degree from the University of Arizona. He has worked as a wildlife technician for AZ Game and Fish Department, and as a soil science lab technician for U.S. Geological Survey. He has experience conducting occupancy surveys concerning Flat-Tailed Horned Lizards and Sonoran Desert Tortoises and has worked on lab analysis for a soil carbon study led by Dr. Laura Norman at the USGS. Before earning a degree, Justin worked as a skilled carpenter for over ten years, mainly focused on residential renovations.

Jonathan Tanis
Ecologist

Jonathan Tanis

Ecologist

BA Cultural Anthropology
University of Southern California 2010

MS Agroecology
Norwegian University of Life Science/Wageningen University 2017

Jonathan is an ecologist and GIS analyst with five years of experience in habitat restoration, originally in California and for the past two years in New Mexico. They have extensive experience both in field surveying and mapping as well as geospatial analysis of field-collected, satellite and UAS/drone data. Recently, Jonathan has been developing GSA's capacity to collect, process and leverage UAS data for environmental monitoring and restoration planning.

  • GIS analysis
  • Plant ecology
  • Field data collection
  • Remote sensing
  • UAS piloting and data processing
  • Vice president - NM Society for Native Plants
Berennice Torres
Finance and Business

Berennice Torres

Finance and Business

BS, Public Accounting
Universidad Autónoma de Baja California, 2003

Berennice has been a Public Accountant since 2003. While living in Mexico after she graduated from Universidad Autónoma de Baja California, she was able to work with international corporations managing both Mexican and US accounting systems. Berennice has been part of the GSA Team since 2009. Her recent responsibilities at GeoSystems include managing all accounting, finance and administrative activities within the company, as well as being one of our main contacts with our South America clients because of her bilingual skills.

Pedro Traviesa
Civil Engineer

Pedro Traviesa

Civil Engineer

Pedro is a recent graduate with a Bachelor of Science in Civil Engineering from San Diego State University, focusing in hydraulics and hydrology. Since 2023, Pedro has been gaining experience as an on-call intern at GSA and is now working in surface water and groundwater modeling.

Scott Waibel, PhD
Hydrogeologist

Scott Waibel, PhD

Hydrogeologist

PhD, Enviromental Sciences and Resources: Geology
Portland State University, 2017

MS, Geology: Geohydrology
Portland State University, 2011

BS, Geology, Cum laude
Portland State University, 2007

Dr. Scott Waibel has been a GSA team member since 2018. He has been involved with academic and professional geologic and hydrologic studies since 2011, with an emphasis on using physical and geophysical measurements in combination with numerical modeling to better understand complex physical processes. He has experience developing and implementing regional and local scale groundwater and multi-dimensional unsaturated flow models. Relatedly, he has experience with contaminant transport modeling. Scott also works on characterizing the hydraulic properties of subsurface soils and bedrock. He conducts statistical analyses of environmental data to help identify trends, patterns, and anomalies in data related to hydrologic processes. His experience also extends to mine waste closure systems. Scott is particularly passionate about projects related to managed aquifer recharge.

  • Numerical modeling
  • Hydrologic budgets
  • Saturated and unsaturated flow
  • Data processing and analysis
  • Statistical analyses
  • Groundwater recharge processes
Will Widener
Ecologist

Will Widener

Ecologist

B.S. Botany (minor in Zoology)
Western New Mexico University, 2005

William Widener is a biologist with over 10 years of experience in environmental consulting specializing in botany and plant taxonomy. Will also has extensive experience performing botanical and biological inventories associated with habitat restoration, rangeland management, mine land reclamation, energy development and transportation planning projects. He routinely performs vegetation monitoring studies, threatened and endangered plant and animal surveys, wildlife presence/absence surveys, wetland determinations and delineations, and noxious weed inventories. Will's broad capabilities and keen attention to detail makes him an invaluable asset to any field-based project.

  • Botany
  • Noxious Weed Inventories
  • T & E Species Surveys
  • Rangeland Inventories
  • Environmental Compliance
  • Wetland Determination & Delineation
Tzung-mow, "Mike" Yao
Senior Hydrologist, Soil Physicist, Laboratory Director

Tzung-mow, "Mike" Yao

Senior Hydrologist, Soil Physicist, Laboratory Director

PhD(1998), MS(1993), Hydrology
New Mexico Institute of Mining and Technology

MS(1988), BS(1985)
Geology, National Taiwan University

Dr. Yao has over 20 years of experience in the design and implementation of laboratory and field studies to determine water movement in the vadose zone. He has developed or refined a number of field and laboratory methods to determine water and solute movement in porous media. He also has expertise in the use of various geophysical methods. Recent responsibilities include the design and implementation of a laboratory and large-scale characterization and monitoring studies for validation of unsaturated flow models and the supervision of over ten monitoring studies to assess net percolation and groundwater recharge rates.

  • Instrumentation, monitoring, and modeling for vadose zone and groundwater hydrology
  • Water and solute movement through the unsaturated and saturated zones
  • Heap leaching instrumentation, monitoring, and hydrological optimization
  • Non-invasive geophysical techniques to measure soil water and solutes in the vadose zone
  • Environmental monitoring systems and instrumentation for vadose and saturated zones
Ben Zimmerlund, MS
Senior Hydrogeologist

Ben Zimmerlund, MS

Senior Hydrogeologist

MS, Hydrology and Water Resources
University of Arizona, 2008

BS, Environmental Geology
Western Washington University, 2003

Ben Zimmerlund has over 20 years of experience in water resources and mining hydrogeology. He has very strong expertise in hydrogeologic characterization, conceptual model development, and baseline field program design and implementation with extensive experience in mine dewatering and pit slope depressurization programs, field hydraulic testing programs, data analysis and interpretation, and 3D geologic modeling. Mr. Zimmerlund also has extensive experience in constructing, calibrating and managing complex groundwater flow models using both MODFLOW and FeFlow to assess groundwater and surface water flow at the local and regional scales.

  • Bedrock hydrogeology
  • Subsurface characterization
  • Conceptual model development
  • Numerical modeling
  • Groundwater monitoring programs
  • Mine dewatering / depressurization programs
  • Well / piezometer design and installation

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