Eight employees at the stricken Fukushima No. 1 nuclear power plant have worked without wearing personal dosimeters since June 2011, while 20 have lost their dose measurement devices, Tokyo Electric Power Co. said Aug. 23.
Eight employees at the stricken Fukushima No. 1 nuclear power plant have worked without wearing personal dosimeters since June 2011, while 20 have lost their dose measurement devices, Tokyo Electric Power Co. said Aug. 23.
TEPCO apologized for the sloppy enforcement of radiation control and its failure to take appropriate measures to prevent a recurrence of such incidents. The plant operator also acknowledged its "slow response" in reporting the oversights to authorities.
The Asahi Shimbun revealed in July that some subcontractor workers were ordered to cover their dosimeters with lead plates at the Fukushima plant in December to keep radiation dose readings low. Those findings were followed by revelations that three employees worked without dosimeters and one dosimeter was lost at the Fukushima No. 1 nuclear plant.
Those developments prompted TEPCO to review dosimeter lending records as far back as June last year.
Two of the eight workers who wore no dosimeters on the ground were TEPCO employees and six were subcontractor employees. TEPCO said six of them forgot to borrow a dosimeter, one of them decided on his own that he didn't need to wear one, and the remaining worker could not get a dosimeter due to mismanagement in the lending process.
All 20 dosimeter losses were by subcontractor employees. Many of the losses occurred during work or while the workers were changing their clothes, TEPCO said.
Three of the lost dosimeters were later recovered, but the rest are still missing, and some details of the incidents remain unclear.
Losing a dosimeter or working without one means correct dose records are unavailable, presenting a serious problem in terms of safety control.
Officials on the grounds of the Fukushima plant were aware of the problems as soon as they arose, but TEPCO's head office in Tokyo failed to notify the Ministry of Health, Labor and Welfare and the Nuclear and Industrial Safety Agency accordingly.
Junichi Matsumoto, acting general director of TEPCO's Nuclear Power and Plant Siting Division, said the utility notified the government authorities of all those cases only on Aug. 23.
"We have taken it seriously that personal doses were not measured properly," Matsumoto told a news conference on Aug. 23. "In retrospect, we were slow to respond."
The health and labor ministry plans to take a tough stance in investigating the matter.
"These are cases where we should have been notified immediately," one ministry official said. "And the cases are so numerous. TEPCO's delayed response is problematic."
"We were notified only today," a NISA official said. "We will review TEPCO's response."