In a meeting of the Japanese Parliament's Upper House Budget Committee, Prime Minister Naoto Kan stated that the government and TEPCO failed to address safety concerns that had arisen prior to the March 11 earthquake and tsunami. An accident in June of 2010 at the Fukushima Daiichi plant revealed weaknesses in the plants systems, but neither the power company nor the Japanese government took any action subsequent to the incident.
On questioning, Kan said that nuclear plants operate on the assumption that diesel generators tasked with keeping the reactors cool will not fail. The failure at the Fukushima plant has serious implications, he said.
The admission was accompanied by a plan for an "alternate capital" in case Tokyo is incapacitated by a future disaster. Kan said that emergency plans must be in place to ensure "continuity of the capital's central functions".