The Nuclear Regulation Authority denied Monday that the Great East Japan Earthquake damaged piping related to critical cooling equipment in the building housing reactor 1 at the Fukushima No. 1 power plant before the tsunami hit.
The NRA made the assertion after inspecting the building to study why a water leak developed near the No. 1 reactor's two isolation condensers after the magnitude 9.0 quake struck on March 11, 2011.
An influential nuclear investigation panel said in a report last year that the leak might have been caused by quake-related damage to the piping for the condensers, but the NRA said the water likely splashed out of the reactor's spent fuel pool during the violent quake. The leaked water was radioactive.