Nuclear power is making a comeback worldwide, but finding permanent storage sites for spent fuel -- which can be hazardous for many thousands of years -- is a huge challenge.

Japan is no exception as it pivots back towards "maximum use of nuclear power" in a safe manner, according to its energy policy, 15 years after the Fukushima disaster.

The government wants to conduct a preliminary survey on Minamitorishima, Japan's easternmost island in the Pacific, to see if it is fit to host a facility.

State-owned Minamitorishima, uninhabited by civilians and off-limits to tourists, has "some unexplored landmass capable of hosting a facility," industry minister Ryosei Akazawa told reporters Tuesday.

The triangle-shaped island surrounded by coral atoll also has some "scientifically favourable traits", the minister said.

A request was later submitted to a Tokyo municipality that administers the island to inspect its land conditions and volcanic activity through geological documents -- the first of a three-part survey to select the ultimate disposal site.

Probes were already conducted in three locations in two of Japan's main -- and heavily populated -- four islands, including two in Hokkaido and another in Kyushu.

Minamitorishima, which is around 1.5 square kilometres (0.6 square miles), is reportedly the first candidate the central government picked at its own initiative.

In January, Japan switched back on the world's biggest nuclear power plant in its central Niigata region for the first time since the Fukushima disaster in 2011.

Finland has built the world's first deep geological repository for spent nuclear fuel, the Onkalo facility where waste is meant to be isolated 400 metres (1,300 feet) below ground.