Japanese Nuclear Emergency Response

An 8.9 magnitude earthquake (the 5th largest earthquake ever recorded) struck Japan last night northeast of the island of Honshu. The quake unleashed a massive tsunami into the Japanese seaboard. As the sun rose in the land of the rising sun this morning, the full extent of the damage and devastation was still being ascertained. Even by the most cautious estimates, a horrible human tragedy occurred: hundreds are believed to be dead and many more have lost their homes.

Potentially making matters worse, the quake damaged several nuclear power plants, forcing officials to declare a nuclear emergency. Officials shutdown at least four reactors along Honshu’s eastern seaboard: Onagawa, Fukushima Daiichi, Fukushima Daini, and Tokai (see the map above). Some reports indicate that as many as eleven reactors have experienced shutdowns. This has left many residents, quite literally, in the dark.

Japan is the third largest producer of nuclear energy in the world, behind the United States and France and generates 30% of its power using nuclear power from 53 reactors (despite being the only country in the world to have witnessed firsthand the damage that nuclear energy is capable of when unleashed via a nuclear bomb). Japan’s lack of natural energy reserves and reliance upon foreign imports is expected to lead to an ever increasing reliance on nuclear power in the future. Some estimates find Japan generating 50% of its power from nuclear energy by 2030.

Japan sits on an area of rampant seismic activity and the nuclear commission pays especially close attention to the possibilities of earthquakes in the siting, design and construction of nuclear power plants. Japanese regulations require plants to be built on hard rock foundations to minimize shaking. Additionally, all Japanese plants are equipped with seismic detectors that trigger an immediate reactor shutdown when a large earthquake occurs. The standards issued for seismic resistance of plants were adopted in 1978 and amended in 2001. The regulations specify requirements in terms of localized ground motion (measured in Gal.) as opposed to the more familiar Richter Scale because there is not always a correlation between amount of energy released (what the Richter Scale measures) and the amount of ground motion locally (what actually causes damage). Still, the NSC concluded that under current guidelines, Japanese plants could survive a quake with a magnitude of 7.75 on the Richter Scale. Today’s tragedy isn’t the first occasion that a nuclear plant in Japan faced a forced shutdown because of seismic activities – for example, the largest plant in the world at Kashiwazi-Kariwa was shut down in 2007 in the wake of a an earthquake measuring 6.8 on the Richter scale.

Under the regulatory policies developed by the Nuclear Safety Commission of Japan (similar to the Nuclear Regulatory Commission in the United States), the central nuclear emergency response headquarters (NERHQ) issues the nuclear emergency declaration with technical assistance from the Nuclear Safety Commission. The declaration is analogous to a declaration of federal emergency in the United States. In a nuclear emergency situation, a joint council is formed that includes the National Government’s representatives from NERHQ, senior nuclear emergency response specialists, and representatives of the Nuclear Safety Commission. The joint council devices an overall plan, provides instructions for resident evacuations, guides emergency services, and directs the armed forces. Under the current emergency order, 3,000 residents have been evacuated near the Fukishima plant.

It seems that the highly engineered plants in large part resisted the damaging effects of the quake. Current reports indicate that the plants have not leaked any radiation and remain in fairly good shape. My only hope is that these emergency response agencies do an effective job of dealing with repairing and reactivating the damaged nuclear plants and restoring power to residents. Other than that, there isn’t much to say besides: our thoughts and prayers go out to the residents of Japan.