NIWR at WERC

Exploring morphological impacts of snow and ice bridges used by seismic surveyors on the coastal plain of the Arctic National Wildlife Refuge

  • Project Student PI: Julian Dann
  • Project Faculty PI/Co-PI: Robert Bolton
  • Keywords: remote sensing, Arctic Coastal Plain, ANWR, environmental impacts, stream crossing, snow ice bridges

Abstract

Oil and gas exploration and development in the Arctic National Wildlife Refuge (ANWR) of Alaska have been proposed for decades, however legislation has not permitted exploration since the 1980s. In 2017, the Tax Cuts and Jobs Act opened ANWR to oil and gas leasing, which has increased the need for seismic exploration to characterize the location and magnitude of oil reserves. On October 24 2020, the Kaktovik Inupiat Corporation (KIC) proposed a three dimensional survey over ~540,000 acres along the Arctic Coastal Plain of ANWR.

The Arctic Coastal Plain, the most biodiverse region of ANWR, is a narrow strip of land that runs from the base of the Brooks Range to the Beaufort Sea. The proposed seismic survey will be based out of ‘camps’ consisting of multiple trailers (living quarters), Steiger tractors, Tucker Sno-Cats, Inova Vibroseis vehicles, snow machines, and other equipment required to conduct the survey (geophones, etc.). As exploration progresses across the Coastal Plain, vehicles, including ‘camp’ trailers that are mounted on skis and pulled in a train by Caterpillar D7 steel-tracked tractors, will follow (Raynolds et al., 2020). In areas with insufficient snow cover, movement of these vehicles could cause severe and long lasting damage to the tundra environment.

Previous comparable environmental impact studies of seismic lines from the 1980s have focused on disturbance to vegetation and the active layer. These studies, however, have not addressed the hydrologic impact of using snow and ice bridges to cross streams while relocating these ‘camps’. Creation of fortified ice bridges could result in changes to the timing and magnitude of stream/river discharge, with potential subsequent impacts on sediment load, fish habitat, and water quality.

Using high resolution remote sensing products, we will observe stream bank erosion and surface inundation at and around stream crossing locations. If significant disturbance is observed, we will use topographic, vegetation, and climatological data to assess and predict conditions that result in significant changes to the hydrologic regime. Knowledge gained from this project will be used to inform land managers and direct future research and mitigation projects.