Japan is located in a seismically and volcanically active part of the world – which is why the country’s decision to build nuclear power plants has always been so controversial. As the Fukushima incident showed, a large-scale natural disaster has the potential to be devastating. Recently a team of geologists discovered that a nuclear reactor in Tsuruga is located on an active seismic fault, and now the Japanese government is considering scrapping the plant.
The team assembled by the Nuclear Regulation Authority (NRA) closely studied the tectonic situation underneath the Tsuruga plant and found that it had signs of “geologically recent movement”. According to government guidelines, atomic installations cannot be sited on a fault (for obvious reasons). ‘Active’ faults don’t necessarily have to be currently moving. According to the definition, an active fault is classed as one that has moved within the last 120,000-130,000 years.
In the aftermath of the Fukushima’s disaster, all of the country’s nuclear reactors were taken offline, but recently a couple have been reactivated. While many have undergone regular safety checks in the aftermath of the 2011 crisis, all plants must now get the go-ahead from the newly-formed NRA before they can be restarted.
Speaking to Phys.org, Shunichi Tanaka, head of the regulatory body, said: “I have the impression that we will never be able to go ahead with a safety review (of Tsuruga) for resumption.” If the body does indeed decide to decommission the plant, then it’s possible it could signal the beginning of the end for the country’s remaining plants. The Oi nuclear plant, Japan’s only working atomic power plant, also sits on an active fault.