Update 2 The Japanese earthquake-induced nuclear emergency is growing worse by the hour.
After sustaining heavy damage to its cooling systems during Friday's megaquake, and after problems were encountered when damage mitigators attempted to release pressure that was building up in its reactors, Japan's Fukushima nuclear reactor may now be toying with emulating a 1970's potboiler. Athough information is still spotty, the No. 1 reactor at the Fukushima No. 1 nuclear power plant may be beginning to melt down.
Japan's Kyodo News reported on Saturday afternoon, Japan time, in an article entitled "URGENT: Concerns of core partially melting at Fukushima nuke plant," that there are indications that a reactor core at Fukushima No. 1 is, indeed, beginning to melt down.
"The core at Fukushima No. 1 nuclear power plant's No. 1 reactor may be partially melting, the nuclear safety agency said Saturday," Kyodo News reports. "Radioactive substance cesium was detected around the reactor," they quoted that agency as admitting.
The Fukushima No. 1's reactor No. 1 is only one of five Japanese reactors reeling after the megaquake: three at Fukushima No. 1, two at Fukushima No. 2. ®
Kyodo News has now reported that an "explosion was heard at 3:36 p.m. [Japan time] following large tremors and white smoke" at Fukushima No. 1's reactor No. 1.
"Four people have been injured in an explosion that occurred at the No. 1 reactor of the quake-hit Fukushima No. 1 nuclear power plant," Kyodo News said they had been told by Tokyo Electric Power Company.
In a short clarification published three and a half hours after its first report of an explosion at Fukushima No. 1's reactor No. 1, Kyodo News said that: "Japanese authorities have confirmed there was no explosion at the troubled No. 1 reactor of the Fukushima No. 1 nuclear power plant, top government spokesman Yukio Edano said. The chief Cabinet secretary also told an urgent press conference that the operator, Tokyo Electric Power Co. [TEPCO], has confirmed there is no damage to the steel container housing the reactor."
The blast reportedly occurred in the building housing the reactor, and not in the reactor itself. The news agency also noted that the evacuation area has now been expanded to a 20-kilometer radius around both Fukushima No. 1 and Fukushima No. 2, and that TEPCO has begun a "new cooling operation", filling the reactor with sea water mixed with boric acid.