The Permafrost Tunnel Near Fox, Alaska Expansion Project

The Fox Permafrost Tunnel, now almost 50 years old, will be expanded in the next few years to stimulate research in key permafrost areas. The tunnel, 10 miles north of Fairbanks, Alaska, was excavated in the 1960s by the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) and U.S. Bureau of Mines. It was not excavated to become a natural laboratory, but rather to research excavation methods in permafrost. In spite of the limitations, more than 70 technical papers have been written about the tunnel, including topics on mining and geotechnical engineering, surface geophysics, geocryology, geology, biology, paleontology, paleoclimatology and Mars permafrost studies. It does provide a good example of yedoma permafrost seen throughout the Interior Alaska and Siberia, with high ice content, organic-rich loess and massive ice features. Beyond the research, thousands of people, both students and leaders, have toured the tunnel to learn about permafrost firsthand.

The permafrost tunnel expansion is in response to climate warming as well as long standing issues related to building on permafrost. The main research foci is expected to be on these four critical areas: 1) improving standoff detection technology and surface geophysical methods for monitoring permafrost, 2) understanding how permafrost will respond to warming, 3) improving estimates of carbon stocks and release rates, and 4) developing models of permafrost heterogeneity for engineering.

The expanded tunnel will more than double the current tunnel's length, and is designed to directly incorporate research needs. Some design ideas include: a) detailed 3D map of complex permafrost features, b) extensive baseline mapping and sampling, c) side rooms to allow for permafrost warming experiments, d) boardwalks and gantry above tunnel for test geophysics and remote sensing. In addition to the expanded tunnel, new facilities will be built on site, including laboratories, offices, cold rooms, and a learning center. Combined, these will form the Alaska Permafrost Research Center (APRC). http://permafrosttunnel.crrel.usace.army.mil/