Kurt Tuggle, PE

President, Chief Executive Officer

Laramie, WY | Year Joined: 1992

This is a company where we understand, respect, and appreciate the contributions of our employees, who all have unique backgrounds, abilities, and passions.

While conducting post-graduate research in civil and environmental engineering at the University of Wyoming, I found myself out of money and looking for work. My college advisor suggested I apply to a small local Laramie firm. That firm was Trihydro.

I have lived my entire life in the Rocky Mountains. I’ve always wanted a career that aligns with my love of the mountains and outdoors and allows me to do meaningful work with passionate people. Trihydro gave me the opportunity to have this career. I’m proud to have been part of the Trihydro team since 1992.

Early in my career with the company, I worked on projects as a field technician, construction manager, and junior engineer, which enhanced my understanding of how engineering designs become reality and function in real-world conditions, along with how the company works as a business entity. My experiences working for Trihydro, doing everything from fieldwork to engineering design and project management, have provided me with a solid foundation to perform my current role as the company’s president and chief executive officer.

Away from work, my passions are my family and the outdoors. I’ve been happily married for 26 years and have two fantastic children. I enjoy all forms of exercise and own seven bicycles (wait, okay, maybe eight by now) and at least ten pairs of skis.

George Mathes, PE

Executive Vice President, Chief Development Officer

Laramie, WY | Year Joined: 1998

The “work hard, play hard” mentality was apparent in my first interview, and I knew Trihydro would provide me with the great family environment I was looking for.

When I started college at the University of Wyoming, I wasn’t sure if I wanted to study physics or engineering. During freshman orientation, I noticed that engineering seemed more practical and solution-focused. I have always enjoyed working with people, so I became heavily involved in student government and taught entry-level engineering during graduate school. I ultimately received my bachelor’s degree in civil engineering and my master’s degree in environmental engineering.

I was looking for an opportunity to make a difference with a company when my master’s advisor recommended I apply at Trihydro. I’ve been with the company for over 27 years and have been fortunate enough to help Trihydro grow from a small firm of 42 to over 600 people. I currently serve as the company’s executive vice president and chief development officer. In my role, I help guide the company’s strategic vision, support new ventures, oversee the company’s mergers and acquisitions program, and lead our Business Development and Marketing teams.

Outside Trihydro, I have a wonderful wife, two incredible daughters, and a black labrador named Aspen. We enjoy spending our time hiking, fly fishing, skiing, mountain biking, trail running, and exploring the Wyoming backcountry. Additionally, both of my daughters were competitive swimmers, and I continue to spend many hours officiating swim meets around the state and nation.

Mark Donner, PE

Senior Vice President, Chief Operating Officer

Laramie, WY | Year Joined: 2002

A desire to be close to the activities I love brought me to Trihydro, but the people I work with led to my long-term commitment to the company.

My decision to become an engineer was not shaped by one defining moment, but rather by my personality and strong aptitude for math-related subjects. I earned my engineering degree at Colorado State University, where I met my wife of 25+ years. We met in a concrete lab, and one of our first dates was a road trip to Winnipeg, Canada, for a concrete toboggan competition—about as romantic as it gets.

My family and I have always called the Rockies home, close to loved ones and endless outdoor opportunities like camping, hunting, motorcycling, and snowmobiling. This love for the outdoors has deeply influenced my engineering focus on water resources, mining, mine reclamation, and natural resource management—a passion that led me to Trihydro in Laramie in 2002.

While proximity to the outdoors brought me to Trihydro, it’s the people who keep me here. Over the years, I’ve built strong friendships with colleagues and clients, witnessed the company’s growth, and supported others in achieving their goals. Trihydro is much more than a workplace—it’s family.

As Chief Operating Officer, I lead efforts to support business units, develop talent, and optimize operations to drive continued success.

Outside of work, I cherish time with my family and enjoy the outdoors. I’m often found cheering on my boys at their sports events, grateful that they share my passions as they grow into young adults.

Holly Barker

Senior Vice President, Chief Financial Officer

Laramie, WY | Year Joined: 2017

Trihydro is a company of innovative thinkers and problem solvers. We believe in doing things right and taking care of employees.

Growing up in Southern Colorado, I gained valuable early experience working for my parents’ family-owned pallet and sawmill business. This exposure allowed me to participate in the daily operations and acquire knowledge of accounting, financial management, and capital investment, which fostered my interest in business.

Upon entering the University of Wyoming, I initially pursued engineering, following in my father’s footsteps, but soon recognized that my passion lay in business administration, prompting a change in major. Early in my career, I held numerous positions in banking, fiscal management, and financial analysis, subsequently advancing my education in accounting to strengthen my understanding of the language of business.

Throughout my professional journey, I transitioned into the grant and non-profit sectors, where I realized my passion for small business environments. In 2017, I joined Trihydro as a project accountant, motivated by the company’s alignment with my own values and its culture of innovation and employee care. My tenure at Trihydro has been fulfilling and dynamic. I am very grateful for the opportunities Trihydro has provided me over the years and am excited to play a part in helping it continue to grow in the future.

During my time off, I enjoy outdoor activities with my husband and two sons, including soccer, boating, camping, and hiking. I often travel back to Southern Colorado to spend time with my extended family. My favorite memories are usually made in the mountains where there’s no cell and internet service.

Kristie Twitchell

Senior Vice President, Chief Information Officer

Laramie, WY | Year Joined: 2003

Trihydro is not just a place where I work—it’s part of my family.

Growing up, I loved business, accounting, math, and computers. My high school business teacher suggested I major in computer information systems. I graduated from college with a degree in management information systems and came to work for Trihydro.

I worked for Trihydro’s helpdesk early in my career with the company. My first week on the job, I had an incident with a printer and ended up covered head to toe with ink. I have managed servers and databases and built our first intranet and project website, Project Direct. Today, I spend most of my time helping the company use cloud computing to its advantage. What I am most passionate about is optimizing processes and working efficiently. I once gave a presentation titled “Working Myself Out of a Job.” I am still working toward that goal today.

My experience working for Trihydro, doing everything from Helpdesk to system administration to developing, has provided me with a solid foundation for being the company’s chief information officer.

My passion outside of work is my family. We love spending time outside, living close to our families, and working on our house.

Brad Mallberg, Esq.

Senior Vice President, General Counsel, Legal & Contracting

Laramie, WY | Year Joined: 2011

I’m most excited about Trihydro’s continued diversification and expansion of our technology
services.

From an early age I wanted to be an astronomer, especially after seeing the cool telescopes in the Sears
Catalog. That dream faded when, year after year, I never got a telescope for Christmas despite always
asking for one.

I earned a B.S. in Biology from the University of Houston, initially planning to pursue a career in medicine.
However, uncertain about my future after graduation, I volunteered for a year at a homeless shelter in
Chicago. During that year, I met a few lawyers volunteering their time with the Chicago Coalition to end
Homelessness. The impressive expertise these lawyers contributed inspired me to pursue law school.

After graduating from law school at the University of Nebraska, I worked in private practice for about 5
years in Lincoln, Nebraska. My wife is from Wyoming, and we had always hoped to return to the state. In
2011, I joined Trihydro as Associate General Counsel. Now as General Counsel, I enjoy collaborating with
senior management and project teams to chart the direction of the company and solve problems.

Outside of work, I enjoy spending time with my wife, two daughters, and son—they are my top priority. I
am also passionate about learning and reading about history, politics, and foreign policy.

Eric Worden

Senior Vice President, Petroleum and Petrochemical Services

Laramie, WY | Year Joined: 1993

I appreciate Trihydro’s strong commitment to professional development, which has provided meaningful opportunities to grow, lead, and take on new challenges throughout my career.

I was originally recruited by the University of Wyoming to play defensive line, but switched to offensive line. During my time there, we went to three bowl games and had back-to-back WAC Championships in 1987 and 1988, with Top 10 national rankings. Football gave me a lot—I met my wife while working summer maintenance at the athletics department and earned my B.S. in range management. It also led me to my first job at Trihydro.

After graduating, I answered a two-line ad in the local paper for an environmental technician position. I was hired in 1993 and began conducting groundwater monitoring for refineries in California and Wyoming. Over time, I moved into project management, then to team leader, and now serve as senior vice president and business unit leader of Trihydro’s Petroleum and Petrochemical Services Business Unit.

I’m proud of the journey I’ve taken with Trihydro. Much of my professional growth stems from lessons learned on the field. My coach, Paul Roach, believed football was about more than wins and losses—it was preparation for life. The game taught me to work as a team, trust others, handle adversity, and believe in myself.

Allison Riffel, PE

Senior Vice President, Industrial and Chemical

Lakewood, CO | Year Joined: 2004

Working with great people was what drew me to Trihydro, and it is also why, after 20+ years, I have continued to make Trihydro my home.

In high school, I attended an environmental engineering summer camp at the New Mexico Institute of Mining and Technology, which hooked me on my future profession. I was excited to better understand the field of bioremediation, especially of recalcitrant compounds. It was the perfect combination of working toward a greater goal using my math and science skills.

I earned a bachelor’s degree in environmental engineering with a leadership certificate from Northwestern University, where I worked on bioreactor studies involving the degradation of polycyclic aromatic hydrocarbons. I have a master’s degree from the University of Colorado—Boulder, where my thesis was on the aerobic biostabilization of dense non-aqueous phase liquid polychlorinated biphenyls. During my master’s education, I also learned that I loved living in the mountains of Colorado.

As a business unit leader and senior vice president of the Industrial and Chemical Business Unit, I have the pleasure of stewarding quality and responsiveness for our clients and projects and providing a great place for our staff to grow their careers. I lead our management team’s business development efforts to foster growth for our diverse teams. My favorite responsibility is acting as the project director and client manager for our key relationships within my business unit.

Jeremy Sell, PE

Senior Vice President, Air and Process Services

Laramie, WY | Year Joined: 2000

I believe our strength as a company comes from the commitment and talent of our people.

The University of Wyoming (UW) brought me and my now wife to Laramie, Wyoming in 1995. Going into my final year of college, I sent out a few resumes in response to open positions in the area, thinking I needed to work on my interview skills and that it might take some time to find a job. A couple of months later, I had a message on the answering machine asking me to come in for an interview with Trihydro. Little did I know that this interview would lead me to where I am today.

I began working as an intern at Trihydro in December 1999 while finishing my wrestling career and chemical engineering degree at UW. Having started as an intern and growing my way through the company, I have worked as a field technician, field engineer, project engineer, and project manager. These experiences have provided me with a unique understanding of the various roles we have in our company and of each employee’s importance in making Trihydro successful. This understanding is something I use every day as the business unit leader for our Air and Process Services Business Unit.

Outside of work, I enjoy spending time with my family and being outdoors. We love having the university here in town and being able to attend as many Cowboys and Cowgirls games as we can.

Andy Smith

Senior Vice President, Legacy Site Management

San Luis Obispo, CA | Year Joined: 2018

Trihydro has consistently offered me growth opportunities and supportive colleagues, making it a rewarding place to build a career where effort leads to results.

My professional career began at the age of 18 with my enlistment in the Navy. During six years of service as a hospital corpsman, I obtained certifications as an EMT and pharmacy technician, focusing on providing medical support to Marine units. After my time in the military, I attended the University of Wyoming, where I explored majors in biology and geology before discovering my passion for chemistry. I ultimately graduated with a degree in chemistry as well as environment and natural resources, beginning a new chapter shaped by diverse experiences and a dedication to scientific exploration.

I began my professional journey in 2007, joining Trihydro’s chemical data evaluation team and launching my career as an environmental consultant. Over the years, I have had the opportunity to contribute to several large and complex projects in Montana, Ohio, and California. In 2014, I explored a different career path but ultimately returned to Trihydro in 2018. Today, I manage and support a business unit dedicated to overseeing complex projects, with responsibilities ranging from permitting and compliance to full-scale remediation and supporting property transactions.

When I’m not at work, I enjoy spending time with my family and caring for our small farm, which is home to goats, chickens, pigs, cows, dogs, and even a stray cat. Whenever we find the time, we love to set out on road trips across the West, discovering new places and experiences together.

Tammy Reed, PE

Senior Vice President, Infrastructure and Natural Resources

Laramie, WY | Year Joined: 2004

Trihydro is rooted in values of adventure, dedication, and connection, which align with my personal journey and commitment.

My story began when I was six years old, on a memorable road trip from Douglas, Wyoming, to Big Lake, Alaska. My dad, an avid outdoorsman, chose the rugged Alaska Highway route, starting in Dawson Creek, British Columbia. We traveled in a single-cab pickup with a camper shell, towing a camper trailer. Over ten days, we fished, camped, and soaked in the wild northern landscapes. The fresh air, endless forests, and sense of adventure left a lasting impression on me. More than anything, I was inspired by my dad’s adventurous spirit and deep love for family.

That early inspiration never faded. When he suggested engineering as a career, I listened closely. Enjoying math and science in school, I asked him which profession would combine those interests. He recommended engineering, and from that moment in eighth grade, I knew it was the path I wanted to follow.

I earned both my bachelor’s and master’s degrees in civil engineering from the University of Wyoming and chose to build my life in Laramie, a place I love and where I could raise a family. In 2004, I joined Trihydro. Today, I’m proud to lead our Infrastructure and Natural Resources Business Unit, carrying forward the values of adventure, dedication, and connection that shaped my journey.

When I’m not working, you’ll find me spending time with family and friends, exploring new places, diving into a good book, or enjoying great food.

Shane Zumpf

Senior Vice President, Technology Services and Solutions

Laramie, WY | Year Joined: 2010

Trihydro was the perfect fit and for the past 11 years, I’ve grown to love the company and the co-workers I interact with every day.

My professional journey as a software engineer began at Colorado State University (CSU). I had hopes of becoming an electrical engineer (EE) and one of the prerequisites for the EE degree was a software development class. Taking the class was eye-opening for me. I found software development appealed to both my logical and creative sides. I decided to switch my focus to computer science after completing that first class and eventually graduated with a degree in computer science after four years at CSU.

After graduating, I worked with Micron Technologies and later with Thomson-Reuters. Eventually, my wife and I moved to Laramie where I wanted to find a local job where I could make a difference in the environment and in people’s lives. Trihydro was the perfect fit and for the past 11 years, I’ve grown to love the company and the co-workers I interact with every day. I currently serve as the Technology Services and Solutions Business Unit Leader. In my role, I help to build and guide the vision for Trihydro’s software development products and consulting services that focus on transportation and environmental solutions.

Outside of work, I focus on spending quality time with my wife and our menagerie of pets including horses, dogs, and cats. We enjoy spending time outdoors hiking, trail running, rock climbing, mountaineering, traveling, and skiing.

Gregg Osland

Vice President, Mining Services

Anaconda, MT | Year Joined: 2024

Trihydro’s “Code of the West” and its commitment to the outdoors, environmental stewardship, and personal well-being deeply align with my values, and I’m honored to be part of such an exceptional team.

I was born in Columbia, South Carolina, and raised in rural Red Bank, where most families worked in manufacturing, including Safety-Kleen, where I’d later begin my career. My father was a self-taught machinist, and though money was tight, our home was rich in love, creativity, and a garden that helped fill the gaps. From a young age, I learned to work with my hands and imagination.

Although our family’s budget was tight, my parents gave me three things that had an indelible impact on my life: a fishing rod, a trombone, and private lessons with gifted teachers. Through music, I learned discipline and perseverance. After high school, I planned to become a fishing guide in Alaska—until a university band director heard me play and offered a scholarship. College, once out of reach, became possible.

Soon after, I met my future wife and decided on a more stable path, joining Safety-Kleen in 1991. My career since has taken me across the U.S. and the Caribbean, working with amazing clients in oil and gas, manufacturing, mining, and government sectors. The people have always been my favorite part.

I had long respected Trihydro’s high standards and client-focused approach, so when the opportunity arose to join the company in 2024 through its acquisition of Alloy’s Engineering Division, I was excited to come on board. I now serve as the business unit leader for the mining services team.

My wife and I have two sons and a grandson. I enjoy national parks, fishing, cooking, music, rock hounding, and gemstone cutting. If you’re ever in southwest Montana, I’ve got a spare fishing rod ready!

Brian Pelan

Vice President, Operational and Service Excellence

Laramie, WY | Year Joined: 2019

Trihydro has provided me with the opportunity to integrate my passions for the outdoors, community involvement, and helping others.

As a child, I had a wide range of interests, from mechanics and teaching to science and cooking. I was always curious about how things worked, which sometimes led to trouble, like dismantling a working lawnmower or cooking up questionable meals. Fortunately, my parents encouraged my curiosity while reminding me to think about safety.

I learned about a new environmental science program at Slippery Rock University in high school. It combined geology, chemistry, biology, math, and safety—subjects I was excited to explore. That program set the foundation for a career that continues to evolve.

I started in manufacturing as an environmental, health, and safety professional, which opened doors to roles in engineering, business operations, and sustainability. Later, after working with Trihydro on several projects, I was drawn to the company’s culture and joined the team.

Today, I serve as Trihydro’s Operational and Service Excellence Director, focusing on strengthening safety and quality systems that help our teams deliver exceptional environmental services.

Outside of work, I enjoy volunteering with Rooted in Laramie and the Laramie Police Department Foundation, and I spend as much time as I can outdoors—snowmobiling, fishing, biking, camping, and hiking.

Karissia Kersey

Vice President, Human Resources

Laramie, WY | Year Joined: 2002

Trihydro works hard to create a culture of safety, diversity, professional/leadership growth, and wellness. I am excited to be part of a team that will continue to strive for the title of ‘Best-in-Class!’

When I was young I had a very romantic view of life as an archaeologist. I wanted to travel the world to remote locations and unearth new, undiscovered civilizations. I also had a strong desire to raise a family and over time, the realist in me matured and I decided to obtain a degree in Communication from the University of Wyoming.

After spending time at home with my children, I joined Trihydro’s Accounting Team in 2002, working in accounts payable, invoicing, and employee expenses. It didn’t take long for me to recognize what a great company I joined, and I quickly fell in love with the culture and the feeling of ‘family.’

When Trihydro opened a position in the Human Resources Team in 2004, I wanted to be part of a team that could help shape and champion our culture. Now, I hold two professional certifications in Human Resources and am able to apply that knowledge in my current role as Human Resources Director. Trihydro works hard to create a culture of safety, diversity, professional/leadership growth, and wellness. I am excited to be part of a team that will continue to strive for the title of ‘Best-in-Class!’

Outside of Trihydro, I love to travel to new and exciting locations and spend quality time with my family and closest friends. I am blessed to live in a community that offers a wide variety of summer and winter outdoor activities. On weekends you might find my family and me attending college or high school sporting events, downhill skiing, snow-shoeing, hiking, biking, fishing, paddleboarding, kayaking, and camping.