https://phys.org/news/2018-07-antarctica-nuclear-nukey-poo.html

By the late 1950s nuclear power was viewed with optimism, as an exciting new solution to both the world's energy and social problems. The Antarctic Treaty was signed in 1959, designating Antarctica as a place for international scientific cooperation. Both the USA and USSR were original signatories, and both were concerned about the possible use of nuclear weapons in the far south.

The Antarctic Treaty therefore included freedom of inspection of all facilities, and stipulated "any nuclear explosions in Antarctica and the disposal there of radioactive waste material shall be prohibited".