2624 Heartland Drive
Sheridan, WY  82801
(307) 672-7133 Office
(307) 672-7143 Fax


Firm Principal

P. Joe Gerlach, Principal, Geologist

  • M.S., Hydrogeology, South Dakota School of Mines and Technology
  • B.S., Geology, Miami University of Ohio
  • Licensed Professional Geologist, Wyoming
  • MSHA-Certified (Surface/Coal Mining)

Mr. Gerlach is the principal of ATC, and has amassed a broad range of expertise in geology, hydrology and mining engineering.  Joe’s experience of more than 35 years includes mining and engineering management, municipal and industrial water resource development, and technical investigations in the geosciences.  Initial experience as a coal mining employee was formative in Joe’s decision to serve clients as a private consultant, and that experience has proved valuable for providing turn-key solutions to engineering and permitting challenges routinely faced by mining companies.  Joe’s management skills have resulted in continued success and forward expansion for ATC regardless of economic conditions, a testament to his recognized expertise in the industry and ability to provide quality work products to our clients.  ATC routinely relies upon Joe for senior technical advice, as well as insight into the broad spectrum of issues that arise on large-scale projects.

Firm Managers

Julie Gerlach, Landman

  • Studies in civil and architectural engineering, University of Wyoming
  • MSHA-Certified (Surface/Coal Mining)
  • Wyoming Public Notary

Ms. Gerlach joined ATC in 1993, bringing more than a decade of experience in regulatory permitting, legal estate research, surveying, and GIS.  Julie provides efficient, timely, and thorough legal estate research to prepare adjudication materials for mine permitting, property transfer and water rights matters.  Her ability to navigate complex records from multiple agencies results in comprehensive legal estate research with no stones unturned.  She routinely uses her research to develop negotiation strategies that often entail a tangle of surface and mineral ownership, water rights issues, and infrastructure matters.  Julie is our in-house expert in mining permits that consistently are accepted by regulatory agencies with minimal follow-up.  ATC relies on Julie’s long-term expertise in drafting and GIS to produce interactive, digital materials that are used by clients, partners and regulators for analytical and archival purposes.

Steve Stresky, Hydrogeologist

  • M.S., Hydrology, University of New Hampshire
  • B.S., Geology and Geophysics, University of Wyoming
  • Certified Professional Geologist, Wyoming
  • Licensed Geologist and Hydrogeologist, Washington
  • MSHA-Certified (Surface/Coal Mining)
  • OSHA-Trained (Hazardous Waste Operations and Site Supervisor)

Mr. Stresky joined ATC in 2004, bringing more than 20 years of broad experience in hydrology, geology, and geophysics to the firm.  His past experience includes oil and gas exploration, groundwater resource development, contamination assessment and environmental remediation that spans a variety of geologic settings in the mountain west, New England, the west coast, and numerous international locations.  His experience is applied at ATC to aquifer characterization, quantitative hydrology, geologic characterization, and permit management for mining, environmental and water resources projects.  Steve has specific expertise in groundwater modeling, well hydraulics, environmental assessment, landfill characterization, and risk-based contamination evaluation.

Michael  Terry, Geologist

  • B.S., Geology, University of Wyoming
  • Geologist in Training, Wyoming
  • MSHA-Certified (Surface/Coal Mining and Pond Inspection)
  • OSHA-Trained (Hazardous Waste Operations)

Prior to joining ATC in 2000, Mr. Terry accumulated 14 years of experience in environmental laboratory support services that include environmental sampling management, regulatory compliance, and impact assessment of groundwater and surface water throughout the western United States.  With his distinctive insight into laboratory procedures and aqueous geochemistry, Mike has become our authority on the chemical characterization of natural systems as well as those impacted by contamination.  Mike combines his geochemical expertise with his geologic background on a wide variety of projects that involve hydrologic and geologic characterization, industrial compliance, and environmental assessment and clean-up.  His hydrologic assessment expertise has been applied to numerous evolving mining projects that date back to the 1980s.

Professional Staff

Bob Giurgevich, Senior Scientist & Project Coordinator

  • B.S., Biology, Bellarmine University
  • Ph.D., Botany, University of Georgia
  • MSHA-Certified (Surface/Coal Mining)

Mr. Giurgevich joined ATC in 2006 after 25 years with the Wyoming Department of Environmental Quality, most of which as District Supervisor of the Land Quality Division.  His regulatory experience is well-recognized in Wyoming, and gives ATC a unique advantage in solving regulatory challenges associated with mining and reclamation.  A natural evolution for Bob has been tackling inter-agency negotiation, including the development of multi-state communications and negotiations strategies necessary for the successful completion of projects that span state borders.  His extensive expertise in vegetation provides ATC with tools in providing turn-key baseline and reclamation characterization for mining projects.

James Kunsman, Engineering Technician

  • Associate of Applied Science, Drafting, Northern Wyoming Community College

Mr. Kunsman has been with ATC since 2006.  Before joining ATC, James provided field assistance for a petroleum service company, giving him familiarity with drilling and field programs comparable to those implemented by ATC.  Mr. Kunsman assists in the design and drafting of all types of maps and drawings that are routinely packaged in deliverable products, using his formal training in drafting to utilize the most efficient approaches for AutoCAD design, GIS, and mapping analyses.  He also assists in AutoCAD database development and data-entry tasks.  James has an artistic ability that helps produce drafting products that are easy to understand and routinely complimented by ATC’s clients.

Andy Patceg, P.E. , Water Resource Engineer

  • M.S., Civil Engineering Water Resources, South Dakota School of Mines and Technology
  • B.S., Civil Engineering, South Dakota School of Mines and Technology
  • Licensed Professional Engineer, Wyoming, Georgia
  • MSHA-Certified (Surface/Coal Mining)

Mr. Patceg joined ATC in 2013. He brings over 6 years of experience in analysis of storm water runoff through hydrologic and hydraulic modeling, storm water infrastructure inventory, and stream habitat assessment. He has proficiency in AutoCAD Civil 3D design and has been involved with multiple stream restoration projects. Andy brings substantial knowledge and experience with ESRI ArcGIS and is familiar with interoperability among GIS, AutoCAD and other software programs. He has conducted multiple spatial analyses using GIS data and has built tools within ESRI ArcGIS Model Builder to automate processes and improve efficiency. His water resources and database management skills compliment his experience and talent utilized for engineering projects.

Cathy Reed, Lands Assistant

Mrs. Reed has been with ATC since 2007.  Cathy brings legal estate research and abstracting knowledge to ATC as well as many years of experience in event coordination and management.  Cathy utilizes her expertise in title research and organization to maintain digital land management systems supporting mining permits and legal documentation.  Cathy uses an organized system of research to efficiently compile records from local, state and federal agencies that include surface and mineral estate, title history, and property easement information.  Cathy has patience and an attention to detail that are critical to assuring that this legal information is accurate and comprehensive.

Tiffany Shaw, Engineering Technician

  • Associate of Applied Science, Veterinary Practice, Northern Wyoming Community College
  • MSHA-Certified (Surface/Coal Mining)

Prior to joining ATC in 2007, Ms. Shaw spent seven years with an analytical laboratory collecting field data to characterize and monitor weather and water quality for Wyoming coal mines.  At ATC, Tiffany manages compliance sampling for surface-water and groundwater discharges, including quality control coordination, instrumentation calibration, sample management, data entry and reporting.  She is experienced with meteorological station instrumentation and related field maintenance, remote data acquisition and troubleshooting of field installations.  Tiffany’s data management skills are utilized in the office to consistently ensure error-free report deliverables to clients and environmental compliance agencies.