Our Team

Mark Lewis
President

Mark joined Det'on Cho in 2019 as Chief Financial Officer before becoming Chief Operating Officer in early 2022 and President and CEO in May 2023. Mark's focus during his tenure has included implementing a continuous improvement program for operational excellence and driving strategic investments to maximize growth and diversify Det'on Cho's businesses.
Over his 15 years in the North, Mark has developed significant experience with Northern companies, including leadership roles in finance and accounting for a local airline, a diamond mine, and a Western Canada-based accounting firm. Mark has also served as an auditor for various non-profit, government, and private businesses.
Mark serves as Treasurer of the Northwest Territories and Nunavut Construction Association and has served on boards of several Yellowknife-based non-profits.
Mark has a business degree from Memorial University in Newfoundland. He lives in Yellowknife with his wife, their two sons, and their dogs, and he enjoys cycling, golfing, and running in his free time.

Claire Tincombe 
Managing Director

With professional experience as an education and training instructor,
engagement specialist, and social scientist, Claire has lived and worked in Fort Liard and Yellowknife, NT and through this has gained valuable insight into the unique opportunities and challenges present when executing projects in Canada’s north. Claire consistently promotes the value of Indigenous business inclusion
in projects around Yellowknife as well as YKDFN involvement in environmental monitoring, remediation, and training programs.
She is experienced in Indigenous Knowledge and Land Use, community engagement, research, data management, and report writing. She has also served as an engagement facilitator for complex meetings with numerous stakeholders present. Currently, Claire is completing a joint Master of Governance and Entrepreneurship in Northern and Indigenous Areas through the University of Saskatchewan and the Arctic University of Norway. 

Cody Drygeese 
Environmental Specialist

Cody Drygeese is an Environmental Specialist with Det’on Cho Environmental and a proud member of the Yellowknives Dene First Nation (YKDFN), with over ten years of professional experience in the environmental field. He is a beginner speaker of Wiiliideh Yati, the language of the YKDFN. He promotes the value of Indigenous business inclusion in projects around Yellowknife as well as YKDFN involvement in environmental monitoring and environmental management.
Cody spent eight years in the Environmental Department at the Ekati Diamond Mine, first as a wildlife technician administering the Wildlife Effects Monitoring Program (WEMP), then as an Environmental Specialist which had a wide range of tasks and programs, mainly the Aquatic Effects Monitoring Program (AEMP). His technical proficiencies include environmental monitoring fieldwork, wildlife monitoring and wildlife management, bird identification and surveys, water quality sampling, data processing, remote field work, caribou studies and monitoring surveys, wildlife deterrence, boating operations, snowmobile operations, all-terrain vehicle operations, Indigenous Knowledge, Traditional Land Use, research, and final report preparation. Cody has lived and worked in remote northern communities and applies this experience to mitigate and plan for the logistical challenges of conducting work in the Northwest Territories.

Rachael Bakker
Terrestrial Ecology Lead

Rachael Bakker is the Terrestrial Ecology Lead for Det’on Cho Environmental. In this role, Rachael leads and supports a variety of terrestrial projects, such as wildlife monitoring and vegetation surveys. She is also experienced in construction monitoring, water quality monitoring, air quality monitoring, remote fieldwork, scientific research, and regulatory reporting. 
Rachael completed her Master of Environmental Sciences at the University of Guelph, where she studied the biogeochemistry of wetlands and human health in the environment. She received her undergraduate degree in Biology, where she specialized in Plant Sciences. Through five years in the agricultural industry, Rachael is adept at plant and insect identification and assessing soil nutrient issues. She is working towards her professional designation with the Alberta Institute of Agrologists. 

Lauren Newton
Fish and Aquatics Lead

Lauren Newton is Fish and Aquatics Lead for Det’on Cho Environmental. Lauren completed her 2-year Fish and Wildlife Technician Diploma at Fleming College School of Environmental and Natural Resources.
With this Diploma she was able to gain plenty of hands-on experience which consisted of: Nearshore Community Index Netting, Benthic Invertebrate collection, Avian Identification, hands on lab work with many different taxa, and wildlife identification and management skills.
After Lauren graduated, she moved to Yellowknife to start her new career as an Environmental Specialist at the Ekati Diamond Mine. While on site Lauren gained experience with Wildlife Effects Monitoring Program (WEMP), Aquatics Effect Monitoring Program (AEMP), Point Lake Project, and a wide range of other programs that take place throughout the field season. Lauren also worked as a Waste Reduction Analyst with the GNWT – Environment and Climate Change. With this work Lauren coordinated Winter Road and All-Weather Road activities and distributed contracts for transportation of recycling and electronics. She also assisted with the Waste Reduction and Recovery Program Annual Report for 2022-2023 fiscal year.
Lauren’s technical proficiencies consist of bird identification and surveys, wildlife surveys, water sampling, data management, all-terrain equipment operation, remote work, and fisheries work.
Outside of working Lauren enjoys fishing, hiking and camping with her husband and two Labrador Retrievers. 

Matthew Johnson
Environmental Technician

Matthew Johnson is an Environmental Technician for Det’on Cho Environmental. In this role, Matthew has provided technical support for projects both in the field and from the office. With his diverse background and training, he is as adept in a field setting as he is behind a desk and enjoys the variety of helping manage projects and getting his hands dirty.
Matthew completed his diploma in Environmental Sciences at Aurora College in Fort Smith, NT where he received training in plant and animal specimen collection and identification, aerial and ground based wildlife survey design and completion, aquatic organism sampling, necropsy, research, and reporting among other disciplines. He also has experience operating and maintaining remote field camps, vehicles, and equipment in support of fieldwork programs. Matthew is an avid outdoorsman with significant on-the-land experience, and has operated in challenging northern conditions throughout all seasons as a former bush pilot. Going forward he intends to continue his education with a focus on Wildlife Biology, while working towards his Project Management designation.