Six months into the Fukushima No. 1 nuclear power plant crisis, only three of the 11 nuclear plants that decided they needed to improve their sea defenses in the light of the March 11 earthquake have actually started building.
Six months into the Fukushima No. 1 nuclear power plant crisis, only three of the 11 nuclear plants that decided they needed to improve their sea defenses in the light of the March 11 earthquake have actually started building.
New seawalls are currently being constructed or existing walls are being raised at Chubu Electric Power Co.'s Hamaoka plant, Hokuriku Electric Power Co.'s Shika plant and Chugoku Electric Power Co.'s Shimane plant, according to an Asahi Shimbun survey.
But eight other plants that decided to improve their defenses are at the planning stage. Many are still discussing the details of their designs and expect construction to be completed in one to three years.
Those eight plants are Tokyo Electric Power Co.'s Kashiwazaki-Kariwa plant in Niigata Prefecture, the Higashidori plant in Aomori Prefecture operated by Tohoku Electric Power Co. and TEPCO, Tohoku Electric Power's Onagawa plant in Miyagi Prefecture, Japan Atomic Power Co.'s Tokai No. 2 plant in Ibaraki Prefecture, Kansai Electric Power Co.'s Mihama, Takahama and Oi plants in Fukui Prefecture, and Japan Atomic Power's Tsuruga plant, also in Fukui Prefecture.
Most of the eleven plants are basing their new plans on a worst-case scenario of a 15-meter tsunami, but the Hamaoka plant is building an 18-meter seawall. Six nuclear plants are not considering bolstering their sea walls at all. The Asahi Shimbun's survey excluded the Fukushima No. 1 and No. 2 plants.
Immediately after the start of Fukushima crisis, the Nuclear and Industrial Safety Agency asked all utilities to implement extra emergency measures at their nuclear plants, such as deploying extra power-generation vehicles and fire engines.
However, action on longer-term safety improvements appears to be stalled at some plants. In fact, some safety improvements suggested prior to the March 11 earthquake have not been implemented at many of the nation's nuclear facilities.
In the 2007 Chuetsu-Oki Earthquake, emergency operations were hindered when a door to an emergency control room at the Kashiwazaki-Kariwa plant became stuck. Insights gained from that crisis informed the use of earthquake-resistant technologies in the construction of the emergency management building at the Fukushima No. 1 plan that has been used as the main base for operations since March 11.
Only three other plants--the Kashiwazaki-Kariwa plant, the Hamaoka plant and the Tokai No. 2 plant--are equipped with such technology.
Six plants, including the Shika plant and the Ikata plant, have decided to erect earthquake resistant buildings, and some of them have already started construction, but the remaining seven plants are still uncertain of the necessity of the buildings and discussing whether to follow suit.
There is also great variation in the disaster-response planning by local authorities with nuclear plants in their areas. The Fukushima crisis uncovered flawed assumptions behind the Emergency Planning Zones (EPZ) stipulated by the government's pre-quake plans for a nuclear disaster. Those zones were supposed to cover localities within an 8- to 10-km radius of a nuclear plant, but the Fukushima no-entry zone was eventually extended to a 20-km radius around the plant.
Many municipalities have asked the Nuclear Safety of Commission of Japan for revision of the EPZ framework and new guidance on dealing with a multiple disaster on the scale of March 11, but that revised advice is not yet available. The commission has said it will review the EPZ by October and issue new guidance by next March.
In the meantime, several municipal governments have taken matters into their own hands. In May, the prefectural government of Kyoto expanded its EPZ from 10-km to 20-km around the Takahama and Oi plants. The Nagasaki prefectural government extended its planned evacuation area from 10-km around the Genkai plant to a 30-km radius.
The existing disaster prevention guidelines were revised in 1999 when a nuclear incident occurred at a nuclear facility operated by the nuclear fuel processor JCO Co. It did not envisage the possibility of the extended radiation leaks seen at the Fukushima plant.
Haruki Madarame, chairman of the NSCJ, said: "The current guidance contains numerous problems such as assuming that people will be able to take refuge inside (their own homes) over the long-term. We need to learn lessons (from the Fukushima accident)."