The government Friday urged municipalities and companies to flesh out preparations for a massive earthquake that could occur off the Pacific coast, including evacuation plans for areas that may not be affected by the initial temblor.
Based on guidelines released the same day, local governments and companies will consider their responses according to the scale of a potential disaster, with the most serious case assuming a quake exceeding magnitude 8 along the Nankai Trough, which extends from off the coast of central Honshu to the country's southwest.
The government estimates there is a 70 to 80 percent chance of a magnitude 8 to 9 quake occurring along the trough within the next 30 years.
In the worst case scenario, the quake could produce massive tsunami waves over 30 meters high, possibly killing up to 323,000 people, according to the estimate.
As previous quakes have first occurred in the eastern part of the trough, residents living in coastal areas that may not be devastated by the initial temblor will also be urged to evacuate.
Local governments will designate areas in which residents will be asked to leave their homes in advance because it could be too late for them to evacuate once an aftershock occurs. The evacuation period for such people is expected to last for about a week.
Companies in unaffected areas will be urged to continue operating as usual while looking out for the safety of their employees.
"We will explain the guidelines (to parties concerned) and make utmost efforts to ensure, together with local governments, the safety of citizens," Chief Cabinet Secretary Yoshihide Suga said at a news conference.
