Climate change has elevated the global dialogue on how to manage our polar regions. Their ecosystems are unique and fragile. Their ice sheets hold 99 percent of the world’s fresh water. Some highly valued natural resources are located in these environments, including an estimated 25 percent of the world’s oil reserves; but whether these resources can be extracted safely—and whether they should be extracted at all—remains in question.
These are not easy regions for any type of operations. The quality of available building materials is quite poor. Materials must be transported long distances, which can negatively impact the harsh but sensitive environment through which transport is conducted. It is also extremely expensive to move materials across these regions.
Geosynthetics are playing an important role in polar environments, from practical protection of infrastructure to supporting revolutionary research into the management of contaminated soils.
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As we near Earth Day 2020, we take a look at two projects that stand out to us for the way they address challenges in polar regions–and for how they produce solutions we can utilize in other environments.
GEOTEXTILE BAGS PROTECT ARCTIC ROADS
French and Norwegian researchers affiliated with the intergovernmental innovation organization Eureka sought a way to protect roadway and affiliated infrastructure in Arctic environments. They wanted a solution that would be environmentally friendly and could withstand ice erosion and corrosion.
A three-year study, coordinated with Norway’s renowned research group SINTEF, found geotextile bags to be highly effective. TenCate Geosynthetics served as a partner to the project.
The project area’s polar environment did not offer any large rock for waterfront riprap. The readily available materials consisted of sand, small stones, and soil.
“The aim of the project was to develop a solution that could exploit the availability of these local materials,” said Arnstein Watn, a Research Director with SINTEF.
TenCate specially design the geotextile bags utilized for the study, which was conducted on Svalbard. Some of the bags were installed in the municipality of Svea on a site operated by Store Norske Spitsbergen Grubekompani (SNSK). Researchers from the University Centre in Svalbard (UNIS) and Norwegian University of Science and Technology (NTNU) contributed greatly to the testing and evaluation.
How did the geotextile bags perform?
“The first winter was harsh,” Watn said, “with huge stresses caused by ice erosion. We were not at all sure that the bags would withstand the strain, but when the ice melted in the spring, we were very pleased to see that only a few bags had been damaged.”
Damaged bags were replaced. The next winter was also quite harsh (as is typical) the project team reported strong performance.
Portions of this section were adapted from a Faktotum AS story originally published in Norwegian. It was adapted by Else Lie at the Research Council of Norway for an international, English-language audience. Additional translation support was provided by Anna Godson and Carol B. Eckmann. That article and photograph were reprinted on Geosynthetica with permission.
REMEDIATING SOIL IN ANTARCTICA
The Australian Antarctic Division has been involved in exceptional soil remediation works at Casey Station. Fuel spills have occurred at the site over the years. Very large volumes of fuel must be delivered and stored to support human activities at the station over long periods of time, given the environmental conditions.
Antarctica is a very unique location at which to conduct geotechnical activities. Natural materials—even contaminated ones—cannot be removed from the continent. Less than one percent of the continent, in fact, has soils that are free of ice, which makes even cubic inch of soil that much more important.
One of the fascinating solutions they’ve advanced is to use geosynthetic liners and cover to encapsulate contaminated soil in biopiles. This enables native soil microorganisms to break down the contaminants while preventing the contaminated soil from leaching out.
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Researchers from the Australian Antarctic Division, the University of Melbourne, and Queen’s University in Canada have found great success in this work.
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Dr. Rebecca McWatters, an environmental engineer with the Australian Antarctic Division, brought to the project her expertise in using geosynthetics in managing Arctic soil contamination and helping apply the strategies to the disparate polar conditions in Antarctica.
McWatters came out of the renowned engineering program at Queen’s University, which has contributed significantly to understanding how geosynthetics perform in polar environments.
“[We’ve found] that hydrocarbon concentrations in the biopiles are decreasing by 50% every 500 days,” she said in late 2014.
Since then, the project has continued to reveal strong results and has helped them scale up the work.
The March 2020 update from the Division referred to the newest biopile as a “dirt hotel.” It represents the largest bioremediation construction on the continent. The mega-pile design measures 20 x 40 m and holds 750 cubic meters of contaminated soil.
For additional information on the Division’s work, we recommend following their research updates on LinkedIn.
