The ceiling of Unit 1 has collapsed and an explosion has blown the entire outer structure off of the containment building at the Fukushima nuclear power plant. A controlled release has not prevented what is most likely a major meltdown. Five other reactors are situated nearby but have apparently been successfully shut down.Several workers have been injured in the explosion and black and white smoke can be seen billowing out of the plant.
An increase of radiation levels has been confirmed following the explosion. The hourly radiation within the plant was measured at 1,045 μSv. The hourly radiation leaking from the plant is reported to be equal to the amount permitted in one year.
Currently wind direction is northerly but changes to south easterly (It appears from the picture to have already shifted) tonight and then back to north easterly on Sunday morning. It remains the same on Monday.
It's not just air born radiation that will most likely spread over much of the top half of Japan in the next few days when the wind direction changes. Radiation contamination might also spread into the Philippine sea and North Pacific Ocean. This is because Fukushima is situated at a cross roads of sea currents.
A Japanese environmental group, has documented previous safety problems at the Fukushima reactor complex:
On June 17, 2010, the same Fukushima I-2 reactor experienced a loss-of-power accident. According to Citizens’ Nuclear Information Center, “On June 17, Tokyo Electric Power Company's Fukushima I-2 (BWR, 784MW) scrammed due to a problem with the generator. Power was lost for a time, because the switchover to the offsite power supply was unsuccessful. As a result, the feedwater pump stopped and the water level in the reactor core fell about 2meters. The emergency diesel generator started up just in time, so the Emergency Core Cooling System was not activated. The water level was restored by an alternative pump in the core isolation cooling system.” At least one reactor at the complex, Fukushima I-3, began using MOX (mixed plutonium-uranium) fuel in September 2010.
After a Magnitude 8.9 Earthquake at a depth of 24.4 km just off the coast of Japan that has caused extensive damage, there has been an explosion at the Fukushima Nuclear power plant at 0630 GMT. Reactor 1 had reportedly been having problems with its cooling system after damage from the quake had stopped a main valve from being operational.