Alaska University Transportation Center PROJECT - Institute of ...

Report of activities – Geophysical investigation at 9-Mile Hill study site 1
Alaska University Transportation Center PROJECT
Use of Geophysical Methods in Subsurface Investigations for Arctic/Subarctic
Transportation Planning and Maintaining
Application #1: Highway Planning in Discontinuous Undisturbed Permafrost
Introduction
Report of Activities
Geophysical investigation along the realignment of Dalton Highway
at 9-Mile Hill near Livengood
This report of activities presents the preliminary results of a geophysical
investigation undertaken along the realignment of Dalton Highway at 9-Mile Hill near
Livengood. The principal goal of this investigation is to assess the spatial distribution of
permafrost conditions along the realignment based on the interpretation of geophysical
surveys including the information from boreholes.
The Alaska Department of Transportation and Public Facilities (ADOT&PF) is
investigating the reconstruction of approximately 4 miles of the Dalton Highway between
the mile post (MP) 8 and 12 (Figure 1) to current design standards for providing safer
alignments, grades, and a new asphalt surface. The project area is located about
10 miles east of Livengood and 80 miles north of Fairbanks. The Trans-Alaska Pipeline
parallels the Dalton Highway and is located approximately 1.5 miles to the east of the
project location. The three mile long realignment is sloping gently to the north-west.
According to Péwé (1975) and Jorgenson et al. (2008), the study area is in the
discontinuous permafrost zone. The bedrock is made of highly deformed and weathered
sedimentary rocks, and overlain by colluvial and fluvial gravelly soils, and silt (loess).
Permafrost formed syngenetically during the late Pleistocene is ice-rich with high
occurrence of ice wedges.
Over the last 20 years, the Northern Region Materials Section (NRMS)
conducted four separate geotechnical investigation of the project area including several
boreholes (Schlichting et al., 2006). In 2008, 8 boreholes were drilled for permafrost
sampling to allow the detailed description of cryostructure (Shur and Kanevskiy, 2010).
The ground-truth coming from these boreholes offers a unique opportunity to verify the
capabilities of geophysical methods for permafrost investigation along linear man-made
infrastructures with well-documented borehole data.