2011 Sendai Earthquake And Tsunami, Tōhoku Region, Pacific Ocean

Seismic recordings at six assessed nuclear power plant facilities indicated the plants had been exposed to peak ground accelerations of 0.037 – 0.383 g and peak ground velocities of 6.18 – 52.62 cm/sec.
Fukushima I & II Nuclear Power Plants
Japan declared a state of emergency following the failure of the cooling system at the Fukushima I Nuclear Power Plant, resulting in the evacuation of nearby residents. Officials from the Japanese Nuclear and Industrial Safety Agency have reported that radiation levels inside the plant are up to 1,000 times normal levels, and that radiation levels outside the plant are up to 8 times normal levels. Later, a state of emergency was also declared at the Fukushima II nuclear power plant about 11 km (7 mi) south. This brings the total number of problematic reactors to six, two of which (unit 1 and 3 at Fukushima I) experienced a partial meltdown, A large explosion, thought to be caused by the buildup of hydrogen gas, blew away the roof and outer walls of the Reactor 1 building, releasing a large cloud of dust and vapor, but the reactor itself was not damaged in the explosion. A similar explosion occurred at Reactor 3 of the Fukushima I plant just after 11:00 am local time on March 14th. An exterior wall of the building collapsed, but the reactor vessel was not damaged according to a government spokesperson. At 16:29 UTC on Monday 14 March (14 March 01:29 UTC), the Japanese Nuclear and Industrial Safety Agency announced that the explosion had occurred. The local population was advised by the authorities to stay home until the radioactive situation of the environment is totally clarified. Unlike the other five reactor units, reactor 3 runs on mixed uranium and plutonium oxide, or MOX fuel, making it potentially more dangerous in an incident due to the neutronic effects of plutonium on the reactor and the carcinogenic effects in the event of release to the environment. Tokyo Electric Power Company (TEPCO) is trying to reduce the pressure within the plants by venting contaminated steam from the reactor vessels into the atmosphere. According to Tomoko Murakami, of the nuclear energy group at Japan's Institute of Energy Economics, this would not result in the release of significant radiation. Residents living within a 20 km (12 mi) radius of the Fukushima I plant were evacuated, as well as residents within 3 km (1.9 mi) of the Fukushima II plant. On 12 March, a BBC journalist reported being stopped 60 km from the blast site by police. As of 14 March, about 160 people have been exposed to dangerous radiation levels near the power stations. One plant employee was killed while operating a crane, eight others have been injured and three are reported to have severe symptoms of radiation poisoning. Some local residents and health workers have been diagnosed with mild radiation poisoning.