Tokyo Electric Power Co (TEPCO) has released an interim report in which the company says that no significant damage was caused to the Fukushima Daiichi nuclear power plant by the March 11 earthquake.
The 130-page report, released to the media on Friday, also claims that there was no explosion at the plant following the earthquake. It says that critical equipment in reactors one to four within the Daiichi plant were not damaged by the earthquake, based on the fact that there were few changes to data readings from the monitoring systems until the arrival of the tsunami, NHK said.
The report says the sounds of an explosion heard emanating from No. 2 reactor were, in fact, the sounds of a hydrogen explosion in No. 4 reactor. The utility explains that a sudden drop in pressure detected in the suppression pool was probably due to a failure of the monitoring systems.
The report's release came just after it was revealed that a recent TEPCO simulation concluded that overheated fuel could have eaten through the thick concrete floor in the plant's No. 1 reactor. The news is at odds with what company executives originally told Japanese lawmakers during the height of the crisis.
Meanwhile, the New York Times reports that a number of scientists and nuclear engineers have questioned whether the company's makeshift cooling system is capable of cooling nuclear fuel that could have trickled into the concrete. While the new simulations paint a far bleaker picture than earlier reports, assistant physics professor Hiroaki Koide of Kyoto University Research Institute believes TEPCO's latest assessments are still unrealistic.
"This is still an overly optimistic simulation," Koide told the New York Times. He noted that although TEPCO is playing down the possibility that nuclear fuel may have penetrated the outermost protective barriers, "even by their own simulation, it's very borderline."
Britain's Guardian newspaper reports that the darkening picture of the situation at Fukushima Daiichi has emboldened many of TEPCO's critics.
A series of scathing new reports concluded that TEPCO ignored advice warning that the nuclear power facility was at risk of damage from the tsunami. The reports also accused TEPCO of ignoring recommendations that it should implement improved seawater flooding controls, according to the Guardian.
TEPCO admitted in the report that its countermeasures against a possible tsunami were inadequate. It said the plant could have withstood tsunami up to 6 meters high and that the March 11 tsunami, which was 13 meters high, was far beyond the utility's expectations.
Experts say that the failure of three of the six nuclear reactors at Fukushima Daiichi was caused by seawater, which flooded power supply lines and disabled cooling systems. Japan is a global leader in nuclear power use, with two-thirds of the nation's electricity supply coming from nuclear facilities.© Japan Today