Permafrost Tunnel Research Facility threatened by increased summer rain in Fairbanks

FAIRBANKS, Alaska (KTVF) - Ice wedges, pre-historic animal bones, and frozen plant matter line the walls of a hole dug straight into the side of a hill near Fairbanks.

The U.S. Army Corps of Engineers Permafrost Tunnel was first built in the Goldstream Valley in 1963 to see how well permafrost could act as a bunker during the Cold War.

By the next year, it was turned over to the Cold Regions Research Engineering Laboratory (CRREL).

Originally built 100 meters deep, the tunnel’s size tripled with an expansion project, starting in 2011. Gary Larsen, Operations Manager at the Alaska Research Office of CRREL, said. “We now have almost 350 meters of tunnel.”

“We actually have two entrances and three crosscuts, as well as a gravel room,” he added.

While at first research focused on permafrost as a building material, now much more is being discovered, “like life in extreme environments, like microbes that are part of the Permafrost,” Larsen said. “It’s really kind of cool to think that bacteria can still be viable after having been frozen for 25 thousand years.”

While no researcher is staged permanently at the tunnel, 22 people conduct regular research here.

The facility is also used by the military to determine how permafrost conditions affect its potential efforts. “Understanding where permafrost is, how it reacts to either maneuver, operations, building infrastructure across the arctic, so not just here in Fairbanks, but all the way across Alaska and the arctic around the world,” according to Larsen.

During the summer, the tunnel must be kept artificially cool to maintain its stability. Larsen explained, “When the temperature rises more than 26 degrees, we turn on the refrigeration system to keep the tunnel at about 26 degrees or colder all summer long.”

Now, the facility is under threat from changing conditions in the region. According to Larsen, “Over the last 10 years, we’ve had a lot more rain during the summer than we typically do, and because of all that rain, what’s happening is the rain is coming down the hill. It’s draining in places it didn’t used to. Instead of going into two really large gullies on each side of the tunnel, now it’s coming down right on top of the tunnel itself.”

This water carries thermal energy, which could dig holes through the surrounding permafrost and into the tunnel itself.

Threatening a record of Fairbanks’ geologic past going back thousands of years.

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