Each submarine has up to eight missiles on board and each missile carries up to five nuclear bombs (or warheads) on it. A Trident submarine patrols the seas at all times. The HEU is one of the most dangerous metals on earth and also one of the simplest nuclear materials to work with. These twin traits also make it a security risk for fear that dishonest or terrorist states may develop a nuclear weapon, or that mishaps will trigger a serious accident.
It is also the reason why it has been the subject of non-proliferation treaties to reduce its use. Ingar Amundsen, head of international nuclear safety at the Norwegian Nuclear Safety and Radiation Authority, agrees that it is a question of when, rather than if, sunken submarines will pollute the waters if left as they are. Nuclear submarines also generate noise from the reactor, including coolant pipes, turbines, and steam generation. Unlike the United States and the United Kingdom, Australia does not have a domestic nuclear energy industry, which could provide a highly skilled workforce of nuclear engineers and physicists.
Needless to say, losing a nuclear submarine is not a situation that any navy would want to be in, but if it does, nuclear material on board is not as serious a risk to humans as it would have been if it had been lost somewhere on earth (or even in the air). Nuclear propulsion, being completely independent of air, frees the submarine from the need to come to the surface frequently, as is necessary for conventional submarines. The two nuclear submarines, which together contain one million curios of radiation, approximately a quarter of that released in the first month of the Fukushima disaster, will pose an even greater challenge. However, another nuclear submarine sank during the “damn month of August,” Russian newspapers wrote, but the incident caused little furor compared to the Kursk.
The high cost of nuclear technology means that relatively few of the world's military powers have deployed nuclear submarines. With a draft decree published in March, President Vladimir Putin launched an initiative to erect two Soviet nuclear submarines and four reactor compartments from the silty bottom, reducing the amount of radioactive material in the Arctic Ocean by 90%. It currently rests on the floor of the Barents Sea, a mile deep, with its nuclear reactor and two nuclear warheads still on board. Just 60 miles (97 km) from the border with NATO member Norway, the Arctic port of Murmansk and surrounding military bases became the center of the USSR's nuclear navy and icebreakers, as well as its highly radioactive spent fuel.
The construction of the world's first nuclear submarine was made possible by the successful development of a nuclear propulsion plant by a group of scientists and engineers from the United States in the Naval Reactor Branch of the Bureau of Ships and the Atomic Energy Commission. Therefore, even if a submarine melts, the chances of a tremendous and instantaneous leakage of its nuclear material are very slim. Donors are discussing Russia's request to help finance the project, said Balthasar Lindauer, director of nuclear safety at the EBRD. Nuclear submarines have considerable performance advantages over conventional submarines (usually diesel-electric).
The most recent nuclear subdisaster involved the Russian Kursk, which sank after a faulty welding of a torpedo caused an explosion that then detonated other torpedoes.