The legacies of the Cold War, especially those arising from nuclear activities, still pose a challenge in the Arctic – the site of various facilities and nuclear experiments overseen at the time by both of the world’s superpowers (the Soviet Union and the United States) and home of both of their nuclear submarine fleets. Two of the biggest legacies are nuclear fallout and nuclear waste, both of which are responsible for the high levels of artificial radionuclides still found in the Arctic today. Another legacy problem in the Arctic is the fate of infrastructure built on permafrost, which is seeing a significant reduction in foundation stability in light of global warming.
Ageing infrastructure is increasingly becoming a legacy problem in the Arctic due to global-warming induced climate changes such as thawing permafrost, which substantially reduces the stability of foundations. Researchers estimate that permafrost accommodates 120,000 buildings, 40,000 kilometres of roads, and 9,500 kilometres of pipelines in the Arctic; up to 70 percent of this infrastructure could be at risk by the mid twenty-first century. With nearly 80 percent of its land underlain by permafrost, Alaska is especially at risk, as are Canada and Russia, whose land is respectively 50 percent and 65 percent underlain by permafrost. Thawing permafrost was one of the major reasons behind an industrial disaster that saw 21,000 tonnes of diesel spill into rivers and subsoil near the Russian city of Norilsk on the Taymyr Peninsula after the storage tanks that held this diesel sank into the ground. Permafrost deterioration also leads to other issues, such as thermal erosion, ice-wedge degradation, and thaw slumps, which have also already been documented on highways in the Canadian Arctic. Thawing permafrost causes an estimated $51 million’s worth of annual damage to public infrastructure alone in Canada’s Northwest Territories.
Maintaining infrastructure built on permafrost in the Arctic poses both an engineering challenge and a financial challenge expected to amount to an estimated US $15.5 billion by 2059. The risk of environmental incidents can be minimised through a number of mitigation methods, including heat removal techniques, such as convection embankments. Another solution is to strengthen climate stress performance assessments for future infrastructure projects and adjust them accordingly. Finally, multilateral communication between scientists, governments, business, and local residents is paramount for standardising best practices for building on permafrost and finding a balance between sustainable growth and development.
Nuclear fallout in the Arctic is a legacy of atmospheric nuclear weapons tests undertaken by nuclear powers largely in the northern hemisphere.
Located between the Bering Sea and the Pacific Ocean, Alaska’s Amchitka Island (part of the Aleutian Islands) was used for underground tests. The United States conducted three tests there between 1965 and 1971: the Long Shot (1965), the Milrow (1969), and the largest underground test, the Cannikin (1971), which had a reported energy yield of five megatons.
The Soviet Union’s Novaya Zemlya was the only atmospheric test site in the Arctic; 130 nuclear weapons tests were conducted there between 1955 and 1990 with 224 separate explosives releasing about 265 megatons of energy. The other atmospheric test site in the Northern Hemisphere was in Semipalatinsk, which was located on the steppe of the Kazakh SSR. Recent data has revealed that fallout from the Semipalatinsk test site eventually made its way up to the Arctic via wind.
With regard to waste, before 1993, there were no international laws forbidding countries from dumping radioactive waste into the oceans. As a result, thirteen countries including the United Kingdom, Switzerland, the United States, the Soviet Union (later Russia), Belgium, France, the Netherlands, Japan, Sweden, New Zealand, Germany, Italy, and South Korea participated in this practice from 1946 to 1993.
Other than the above, a number of other incidents and facilities have contributed to marine radioactive contamination over the past century. In January 1968, an American B-52 bomber carrying nuclear weapons crashed into the sea ice near the Thule Air Base in Greenland, dispersing radioactive materials on sea ice in the resulting fire. While most of these materials were cleaned up, some travelled further south over Greenland by wind. Similarly, on 7 April 1989, a fire broke out in the Norwegian Sea aboard the Soviet nuclear submarine Komsomolets, which sank along with the nuclear reactor and two nuclear-warhead torpedoes it carried. In 1982, water leakage following an accident at Building 5 of Andreeva Bay, a base specially built to service nuclear submarines, also caused widespread contamination. Discharges from the United Kingdom’s Sellafield nuclear decommissioning site’s reprocessing activities have been identified as an important source of elevated radioactivity in the Arctic. The site has considerable volumes of spent nuclear fuel and radioactive waste which may still contribute to future Arctic contamination. Finally, two other potential sources of contamination are the K-27 and the K-159 nuclear submarines that remain on the Arctic seabed and still contain spent nuclear fuel in their reactors.
Multiple monitoring and clean-up projects have been undertaken or are underway to help eliminate anthropogenic radionuclides in the Arctic. Firstly, all eight Arctic countries have national monitoring programmes; these programmes show that radionuclides levels are currently lower than they were in the 1970s, 1980s, 1990s, and are further decreasing. Secondly, governments and companies are engaged in important projects to cleanse the environment of hazardous radioactive materials. For example, in the Lepse floating technical base was towed to a shipyard and placed into a safe shelter in a collaborative project between Russia, the European Union, and other partners.
Decontamination is an important item on the agenda of the Arctic Council, which established a Radiation Expert Group (RAD EG) in 2019 and is preparing a report on radioactivity in the Arctic for 2023 as part of its "Radioactivity in the Arctic" project.