Employee Biographies

Work-Life balance is important to the Tansley Associates team. Other than providing our clients with world class service and products, we enjoy living our personal lives to the fullest!

Mark G. Tansley

Mark G. Tansley


Mark is a true 'born and raised' Albertan. After 13 years of working on drilling rigs around the province, he moved on to his father’s business: environmental solutions and production chemicals for the energy industry. Mark was drawn to the challenges presented by oil and gas exploration –one example was the team’s lobbying of the BC Oil and Gas Commission to adopt Alberta’s Drilling Waste guidelines in 2004, resulting in more environmentally-friendly operations.

One of Mark’s favorite parts of TAES is the diverse pastimes of its employees – he works to support each team member’s passions.

Family is of the utmost importance to Mark, whether through continuing the family business or spending time with his wife of 25 years and three children (Mark, Luci and Georgia). Alberta remains a mainstay, too; summer or winter, Mark’s favorite place is the Rocky Mountains.

Hobbies Outside of Work: Mark coaches the St. Mary’s High School Sr. boy’s rugby team and is President of a youth soccer club (Calgary Foothills Soccer Club). He also enjoys sailing with his mates.

Advice for a Recent Graduate: “Find a job that allows for a work/life mix, one which makes you happy. Take time to make something better for someone else, too.”

I Would Change the Planet By: “Ending global unemployment. TAES is embarking on a project with Kiva.com, a microfinance-based loan system which grows the businesses of economically disadvantaged people. It’s important to give back.”



Financial Controller

Holly has been working as the TAES bookkeeper since 2005. She holds an Accounting degree from the Henderson College of Business, and has completed the Petroleum Land Administration program at SAIT Polytechnic. One of the largest projects Holly worked on was the merger of two companies (Mark’s father’s business and another environmental company) into what is now TAES. Holly’s favourite part of the job is her fellow TAES employees; everyone is a pleasure to work with.

Holly has lived in Alberta her whole life. In her spare time, she enjoys golfing and cattle-penning — she is a member of the Chinook Team Penning Association, and keeps five horses at her home. Holly loves riding her horses through Kananaskis Country.

Best Life Achievement: “Traveling to Guatemala with the Hearts & Hands Foundation, building stoves for the Mayan citizens. Many Mayan families still cook on an open, wood-burning fire that produces smoke-filled homes. Consequently, respiratory and eye disease, serious burns, and deforestation occurs.”

I’d Change the World By: “Ending world hunger.”

Advice for a Recent Graduate: “Work hard to achieve your goals!”

Mike Szigety

Mike Szigety

Operations Manager, Vacuum Services

As operations manager of Wabasca Vacuums, Mike’s favourite part of the job is helping customers in the field. He supervises installations, runs safety programs and also manages some of the odorant division. Mike brings 20 years of experience in the vacuum truck industry to TAES, and also has emergency response certifications from CP Rail and Transport Canada. Whether his team is working on injection systems up north or drilling with vacuum trucks, Mike enjoys the problem-solving challenges.

When he’s not working, Mike’s favourite place to be is around a campfire with friends and family — he camps around Alberta often with his wife and children.

Hobbies: Mike has been building racecars since he was 16 years old, and often races them himself on weekends.

I Would Change the Planet By: “Eliminating hatred between people.”

Advice for a Recent Graduate: “When you’ve finished school, don’t feel pressured to take the first job you come across. Broaden your horizons and shoot for the stars. You’re only limited by your vision.”

Don Peterson

Don Peterson

Training Supervisor

Don has been working for the Tansley family since the 1980s, when Mark’s father owned the company (then named T9 Products). He managed the odorant division and now works part-time on various projects. Over the years, Don helped grow the odorant business from a very small division to over 300 customers. He set up odorant sites on monumental projects like the TransCanada Pipeline and the Canadian/U.S. Alliance Pipeline.

Outside of work, Don enjoys camping in his holiday trailer and woodworking. He volunteers as a board member at the Bowden Friendship Centre in Alberta, organizing events and connections within the community. He enjoys the occasional trip to Disneyland, but is always happy to return to his Bowden farm.

Best Life Achievement: Working with his wife on the TransCanada pipeline system in 1986. They’ve now been married 53 years and have 3 children, 5 grandchildren and 2 great-grandchildren.

I Would Change the Planet By: “Achieving peace within the world and a harmonious community for everyone.”

Advice for a Recent Graduate: “Pick a job you enjoy — something you want to wake up in the morning for. And once you find it, always be on time!”

Chad Marshall

Chad Marshall

Senior Operations Manager, Odorant Division

Chad started as an environmental field consultant at TAES for 8 years. Holding a B.Sc. in Geography from the University of Calgary, he began his TAES career as a field work consultant, and moved on to a variety of managerial positions afterward. Chad enjoys handling the varying challenges of odorant projects, as well as the good company of his colleagues.

Outside of work, Chad likes skiing, playing hockey and baseball. His favourite place is Seattle — he makes the trip for the friendly atmosphere, fresh market food and, recently, a Toronto Blue Jays game. He also enjoys travelling with his two boys and fiancée.

A Significant TAES Project: Chad helped install over 240 Nexen Shallow Gas wells during the oil boom in 2005. He managed the Sunshine Oilsands OSE drilling project, and recently facilitated the installation of two pump injection odorizers for the Alberta Newsprint Company.

Advice for a Recent Graduate: “Spend your life working on whatever you’re most passionate about.”

I Would Change the Planet By: “Giving everyone the opportunity for happiness and peace, in spite of differing beliefs.”

Lian Zhao, PhD, P. Eng.

Lian Zhao, PhD, P. Eng.

Sr. Engineer, Environmental Division

Lian currently is Sr. Environmental Engineer at Tansley Associates Environmental Sciences Inc. (TAES). Lian joined TAES in 2013. She was awarded a PhD degree in Environmental Engineering from University of Guelph in 2007. She is a member of APEGA, and a member of the environment committee of APEGA since 2013. She has worked as an environmental consultant for many years and put in some time with non-profit organizations working in the renewable energy and oil and gas industries. She published many papers in peer reviewed journals and gave presentations at conferences. Her professional practice areas are focusing on energy development projects, specifically, drilling waste management, environmental impact assessments (EIA) , phased environmental sites assessment (ESA), remediation, risk assessment, environmental liability assessment, environmental modeling, underground/above ground storage tanks and fuel site environmental management,environmental regulatory compliance, environmental permitting, monitoring and reporting on behalf of clients in various industrial sectors in Canada and internationally.

Advice to recent graduate: develop your discipline based on how to work extremely hard and explore your impassioned legacy for your profession.

I’d Change the Planet By: Universal energy and passions are leading me through a straight learning-growing-becoming path to make positive influence and serve the best interest of those I do care most for.

Connect with me in LinkedIn, twitter, facebook

Jac Leeuwenburgh

Jac Leeuwenburgh

Odorant Supervisor

Jac has been working for TAES since 2000, originally a senior field supervisor in the environmental field. He took the position of Odorant Supervisor for its flexibility and field-work opportunities — and to work with his wife, Carolyn, a TAES odorant technician. Together, Jac and Carolyn travel everywhere from Lethbridge, AB, to Fort St. John, B.C. and as far as Quebec City. They coordinate delivery of odorant to clients, work on clean-up jobs and uphold safety standards.

Jac holds a bio-sciences degree from the University of Calgary, and a land resource management diploma from Olds College. Outside of work, he enjoys racing radio-controlled cars on outdoor tracks, camping in the Albertan wilderness, and spending time with his six children.

Favourite Place: Being in the fresh Rocky Mountain air.

Advice for a Recent Graduate: “Keep it cheap when you start off — no fancy trucks in the oil field!”

I Would Change the Planet By: “Getting rid of the ‘career politician’ by limiting politicians to two terms.”

Kim Wang

Kim Wang

Environmental Specialist

Kim Wang is a recent graduate who joined Tansley’s Environmental Division in 2014. He’s received both his Bachelor’s and Master’s degree in Environmental Science. He studied at Northwest A&F University in China, and then at Memorial University in Newfoundland, Canada. He enjoys the outdoors, anywhere with fresh air and sunshine.

Hobbies: Movies, Basketball, Hiking, and Cooking

Advice for a recent graduate: Being a recent graduate himself, he recommends being patient and continue learning everyday.

If you could fix something about the world: Pollution.