Tunnel vision: BHS geology class visits abandoned railroad tunnel

By JORDAN DAWSON / Bigfork Eagle

Bigfork High School science teacher Hans Bodenhamer's geology class emphasizes practical applications in math and science to help students prepare for a variety of careers including geology, soil science, engineering and architecture.

During the beginning of the year they focused on mapping and surveying skills. Students learned how to use a transit level and make a topographic map of part of the school grounds.

Recently, they put those skills to use again to map an abandoned railroad tunnel near Marion using Suunto compasses and inclinometers.

"It really shows us the potential we have and shows us some types of careers we can do," said junior Alex Johnson. "It's good to get students out to see the world rather than just sitting in a class room."

While inside the tunnel students worked in groups to plot specific points of interest, such as collapses. They also worked together to ensure that the tunnel was better than when they arrived at it by scrubbing away about 80 feet of graffiti on the walls.

"We bond together more as a class when we go on these trips," Johnson said. "You get to know people better. Friendships are made and grown traveling there and back and working in groups in the cave."

In the days following their trip to Marion, the students used engineering software and graphics programs to reduce their survey data and prepare engineering-quality maps. The resulting maps allowed the students to get a different perspective of the tunnel.

"It was really fun because we could see how far under the ground we were and see what all was in the cave," said junior Emily Bermel. "We were able to see how tall and wide it was. You don't really realize how big it is when you're in it. It makes you feel kind of small."

The tunnel is about 1,600 feet long and gradually drops down to a depth of 88 feet. It was last used in the early 1900's to transport logs cut in Pleasant Valley to the lumber mill in Kalispell. The tunnel is still intact, except for the northwest entrance, which is completely collapsed.

"The mapping project was a success," Bodenhamer said. "It was the first time I had tried mapping the tunnel. Last year I had them map a cave. The tunnel was longer, but easier to work in. Like all things I think they would do better if they were to do it again, but that does mean they learned. In review of the whole project I'm really happy."

Later in the year the students will learn to identify rocks, fossils, faults and other formations. In the spring, they will combine that knowledge with their mapping skills and return to the field to make geological maps, develop geological histories for areas, assess geological hazards, and evaluate the potential of contamination to ground water systems.

"Getting my students out into natural settings outside the classroom gives them a greater appreciation of our region's history, ecology, and how the agencies and businesses interact," Bodenhamer said. "I think it will help them make more educated decisions after they graduate."

Though this sounds like rigorous work for high schoolers, the hands-on learning is appreciated by the students.

"I'm an active person and this project gave us the get up and go drive, and that was great," Bermel said. "Most teachers would just give you a worksheet, but Mr. Bodenhamer sent us out there and we had to figure it out on our own. We were able to learn more that way about surveying."