March 13, 2011 |
Japanese officials have begun pumping seawater into a second nuclear reactor at the Fukushima No. 1 power plant 140 miles north of Tokyo to cool the reactor core in a last-ditch effort to stave off a core meltdown. The action indicates that the reactor's normal backup cooling system has failed and is no longer able to supply fresh water to the core. Officials at Tokyo Electric Power Co., which owns the plant, have been struggling to keep six shut-down nuclear reactors cooled because seawater from the tsunami that followed Friday's magnitude 9.0 earthquake damaged the diesel generators that power the circulating pumps.
March 12, 2011 |
Another nuclear reactor at the Fukushima No. 1 facility in Japan has lost its emergency cooling capacity, according to the Associated Press, bringing to three the number of reactors at that facility to fall prey to Friday's magnitude 8.9 earthquake and tsunami. Added to failure of three reactors at Fukushima No. 2, the count is now six overall. So far, the only reactor that seems to pose an immediate risk of widespread danger is one of the two shut-down reactors at Fukushima No. 1, also known as Fukushima Daiichi, which was disabled by an explosion overnight that destroyed the building housing the reactor and the backup cooling system.
March 15, 2011 |
Dangerous levels of radiation escaped a quake-stricken nuclear power plant after one reactor's steel containment structure was apparently breached by an explosion, and another reactor building in the same complex caught fire, Japan's leaders told a frightened population. Authorities warned that people within 20 miles of the crippled reactors should stay indoors to avoid being sickened by radiation. The fast-moving developments at the Fukushima No. 1 (Daiichi) plant, 150 miles north of Tokyo, catapulted the 4-day-old nuclear crisis to an entirely new level, threatening to overshadow even the massive damage and loss of life spawned by a devastating earthquake and tsunami.
March 22, 2011 |
Radiation has been detected in seawater in areas surrounding the earthquake and tsunami-ravaged Fukushima nuclear plant in northeastern Japan, creating one more cause for concern after radiation was found in food items and tap water. Officials stressed that the levels -- which they said would have minuscule impact on the human body even if the seawater were ingested daily over a year -- were not cause for alarm. Tokyo Electric Power Company, which owns the plant, said it detected radioactive iodine-131 more than 125 times higher than the legal limit in a sample of ocean water found about 0.2 miles south of the Fukushima Daiichi plant on Monday, Kyodo News Agency reported.
March 14, 2011 |
Engineers are now pumping seawater laced with boron into two nuclear reactors at Japan's Fukushima No. 1 (Daiichi) power plant 150 miles north of Tokyo and are considering doing it at a third reactor in a last-ditch effort to stave off a meltdown that could release dangerous amounts of radioactivity into the environment. Hydrogen explosions have now occurred at two reactors at the facility. Here's a look at the engineers' efforts and what the potential consequences are, according to various experts.
March 20, 2011 |
Radiation levels at the stricken Fukushima Daiichi nuclear power plant in Japan are still high but may be tapering off, a senior U.S. nuclear official said Sunday. Indications from the plant, which houses six nuclear reactors, were levels in the range of hundreds of millisieverts per hour, said Gregory Jaczko, chairman of the U.S. Nuclear Regulatory Commission. The duration of those levels was unclear. The exposure limit for Japanese workers was recently raised to 250 millisieverts per year.
March 17, 2011 |
Who are the "Fukushima 50" -- the workers trying to take regain control of Japan's stricken Fukushima Daiichi nuclear power plant? Twitter messages and blog posts by the workers' families offer an inkling of the "Fukushima 50," so nicknamed because the 180 employees at the site work in 50-person shifts. One of the workers is a veteran power plant worker, a 59-year-old who volunteered to take on the assignment, according to Jiji Press, a Japanese news wire service, quoting a woman who claimed to be his daughter on Twitter.
March 28, 2011 |
Highly radioactive water is building up in tunnels underneath at least three reactors at the Fukushima Daiichi nuclear power plant, impairing the ability of workers to reestablish power connections at the facility. Officials of the Tokyo Electric Power Co., which owns the facility, also said that tests last week found trace levels of plutonium in soil outside the plant, an indication that the containment vessel of reactor No. 3, the only one that is fueled with plutonium, may have been breached.
March 23, 2011 |
[Update 12:47 a.m.] Tokyo's utility company says black smoke has been seen emerging from Unit 3 of the crippled nuclear plant in northeastern Japan, prompting a new evacuation of the complex. Officials with Tokyo Electric Power Co. said Wednesday that workers from the entire Fukushima Dai-ichi plant have been temporarily evacuated. _________________ Control room lights were on and electronic thermometers were functioning Wednesday at several of Japan's stricken nuclear reactors, marking small but potentially critical steps toward controlling overheated fuel that has been spewing radiation for more than a week.
March 14, 2011 |
The fuel rods at a third nuclear reactor at the Fukushima No. 1 nuclear power plant have been fully exposed to air for short periods of time and at least partially exposed for more than three hours, allowing them to heat up and sharply raising the risk of a meltdown, according to officials of the Tokyo Electric Power Co., which owns the plant. The cooling problems at reactor No. 2 represent the most serious development in the ongoing problems at the nuclear power plant to date, according to nuclear specialist Edwin Lyman of the Union of Concerned Scientists.