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Photos

Snapshots of what’s happening in the Defense Department.

A line of people wearing hard hats walk through a lighted tunnel with a railing.

Permafrost Tunnel

Gary Larson, facility operations manager with the Cold Regions Research and Engineering Laboratory, leads a tour group through the U.S. Army Corps of Engineers Permafrost Tunnel north of Fort Wainwright, Alaska, Sept. 12, 2019. Larson pointed out significant features of the tunnel, the world’s only permafrost tunnel used for researching how permafrost relates to climate change.

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