Workers knew little about criticality 8211; Report

TOKYO, OCT 10: The most senior of three workers blamed for Japan's worst nuclear accident had been taught little about chain reactions wh...

TOKYO, OCT 10: The most senior of three workers blamed for Japan8217;s worst nuclear accident had been taught little about chain reactions which resulted from their faulty operation last month, a report said on Sunday.

The operator of a uranium processing plant where the radioactive leak occurred on September 30 told police that he was briefed about quot;criticalityquot; just once 23 years ago when he joined JCO Co Ltd, the Asahi newspaper said.

quot;I did not understand well what it meant,quot; the 54-year-old worker was quoted as saying in the report, which added to daily revelations about safety violations and omissions allegedly committed by the company.

A JCO spokesman said he had yet to confirm the report about the allegations. A spokesman at the prefectural police, charged with investigating the accident, was not immediately available for comment. JCO earlier admitted the trio, two of them listed in critical condition, used steel buckets to pour 16 kilograms of uranium into settling tanks, starting off aself-sustaining quot;criticalityquot; reaction.

The maximum permissible limit was 2.4 kilograms and it should have been poured through a reserve tower to be mixed with nitrogen gas and slowly filtered.

The senior worker, who was the least affected by the exposure among the three, told police he did not know how much uranium could spark off a critical chain reaction, according to the report. quot;I have never thought about criticality,quot; he said.

The leak at the JCO plant in Tokaimura, 120 kilometres northeast of Tokyo, exposed at least 49 people to radiation in the world8217;s worst nuclear accident since the 1986 incident at the Chernobyl power plant in the Ukraine. It also forced more than 3,20,000 people to shelter at home for 24 hours.

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Police raided JCO8217;s offices last Wednesday, the same day Prime Minister Keizo Obuchi visited the scene of the incident and promised to consider new laws to tighten regulations. The company has been suspected of changing manuals for plant operations without government authorisation,a violation of the nuclear power reactor regulations law.

On Saturday, the government acknowledged it had not conducted on-site inspections at the troubled plant since 1992. Under the law on nuclear facilities, the government should regularly inspect nuclear power plants and nuclear fuel reprocessing plants, but not uranium processing plants.

On Friday, the government agreed to let in the Vienna-based International Atomic Energy Agency IAEA, which offered to help immediately after the radiation leak only to be turned down.