Human error stops cooling functions at nuke plant

TOKYO - The operator of the crippled Fukushima Daiichi nuclear power plant Tokyo Electric Power Co ( TEPCO) admitted that human error was the cause of a pump cooling nuclear fuel being stopped on Monday morning.

The embattled utility also stated on late Monday that in addition to the cooling of nuclear fuel being temporarily suspended, in two of the complex's containment units, the decontamination of radioactive gases was also halted due to the error.

Power failure was blamed in both cases, with TEPCO claiming that one of its workers accidentally pushed a stop button causing power to be cut to the plant's key systems at around 9:47 am Monday morning.

Monday's blunder follows a series of preventable oversights by the utility, including workers overfilling a storage tank to the point highly-radioactive water leaked into the adjacent Pacific Ocean, building shoddy, leaking storage tanks to contain massive amounts of toxic wastewater and allowing rodents to short circuit a switchboard, leading to systems to cool spent fuel rods being offline for almost 30 hours.

Naomi Hirose, TEPCO's president, was summoned to speak before an Upper House committee on Monday to account for the utility's continued gaffes and its plans to contain the huge volume of contaminated water that is collecting on a daily basis - some of which has leaked into the ocean.

"We need to increase the workforce," said Hirose, claiming that the staff at the Daiichi facility in Japan's northeast were over- stretched, "We also believe it's very important to improve their working environment."

Industry minister Toshimitsu Motegi and Nuclear Regulation Authority (NRA) Chairman Shunichi Tanaka also attended the upper house meeting, with Tanaka again calling into question TEPCO's competence.

"The situation at Fukushima Daiichi has not been sufficiently stabilized to reassure the public about safety," the NRA chief told Hirose and the upper house panel Monday.

"We will proceed very carefully with our safety inspections at the Kashiwazaki-Kariwa nuclear plant," Tanaka said.

Tanaka was referring to TEPCO's application to restart the shuttered Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture and insisted the utility provide a safety report by the end of the week.

Monday's saga follows the Secretariat of Japan's NRA, Katsuhiko Ikeda, summoning Hirose on Friday to attend a meeting with NRA officials at which Hirose was chastised following the revelation of yet more leaks from the crippled Fukushima Daiichi nuclear power plant.

Hirose admitted that workers at the Daiichi facility has miscalculated and overfilled a storage tank to beyond it's capacity, causing 430 liters of radioactive water to leak into the ocean a day earlier.

Ikeda told Hirose that TEPCO is monumentally failing to manage the situation at the leaking plant effectively and that more measures needed to be taken.

He also said he was highly concerned that more leaks could happen in the future and urged the company to better make its staff aware of ongoing and changing safety protocols and draft in additional staff from other facilities if necessary.

Hirose once again admitted that human error at the plant was responsible for radioactive materials spreading into the environment.