After a March 11, 2011 earthquake off the shore of Japan’s Northeastern Fukushima Prefecture, magnitude 9.0, a tsunami wiped out homes and businesses, displacing some 300,000 and killing nearly 19,000 others.
The earthquake and resulting tsunami were catastrophic events on their own, but the continuing chain reaction also resulted in a series of failures at the Fukushima Daiichi Nuclear Power Plant, also located on the East Coast. Fortunately, the plant didn’t go into meltdown, as technicians were able to shut down reactors in time, but the cooling pumps failed, which allowed for a dangerous buildup of hydrogen gas. The hydrogen gas reached explosive concentrations, causing severe damage to the containment buildings.
Aside from the obvious damage to the visible structure of the Fukushima Daiichi Nuclear Power Plant, many suspected that the cooling-water holding tanks could be damaged, leaking irradiated water before it could be properly processed. Eventually, this was confirmed, that the cracked holding tanks were leaking some three hundred tons of water into the ground every day.
Unfortunately, due to its proximity to the coast, the Fukushima Daiichi Nuclear Power Plant is especially susceptible to changing weather conditions. Granted, tsunami aren’t a common occurrence, and definitely put coastal residential and industrial zones at a far higher risk than normal. Typhoons, on the other hand, are fairly common, and coastal regions are generally prepared for these. The problem arises when Typhoon Man-yi comes ashore while workers are working hard to repair the damages from the tsunami two years earlier.
In spite of the fact that Typhoon Man-Yi struck further north than Fukushima Prefecture, the nuclear power plant was inundated with rainfall, forcing cooling-water holding tanks beyond their capacity. All told, experts estimate that some 1,100 tons of irradiated cooling water was released into the ground, and therefore, the nearby Pacific Ocean. Experts also say that the water’s radiation level was well below safety limits imposed by Japanese authorities.
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