2011年10月5日水曜日

Tepco concludes own crisis manual useless

An in-house report from Tokyo Electric Power Co. has concluded its emergency manual was useless for handling the nuclear crisis at the Fukushima power plant and that the widely held belief that a hydrogen explosion might have damaged the No. 2 reactor is false.

The report on Sunday indicates the manual was drafted on the assumption that the emergency generators — including the diesel backups — would keep the reactors' cooling systems running no matter what.

At the Fukushima No. 1 plant, however, none of the backup generators for stricken reactors 1 through 4 survived the March 11 tsunami.

According to the report, compiled by an intracompany investigative panel, Tepco first became aware large explosions had been heard at reactors 2 and 4 after 6 a.m. on March 15.

The utility then confirmed that the air pressure in an area near No. 2's containment vessel was falling and also that the upper part of the building housing the No. 4 unit had been seriously damaged.

Subsequent analysis of the data led Tepco to conclude an explosion had occurred at the No. 4 reactor, but it "erroneously recognized" that something akin to an explosion had possibly taken place at the No. 2 unit as well, the report said.

The buildings housing reactors 1 and 3 were destroyed by hydrogen explosions, while that of the No. 4 unit, which was idled for a regular checkup at the time, was also destroyed. The building for the No. 2 reactor still stands.

The draft report was drawn up by an in-house investigation team Tepco set up on June 11.

Tepco reportedly plans to publish the in-house report after submitting it to a panel of seven outside experts.

The Fukushima Prefectural Government is studying ways to estimate radiation contamination in beef cattle by analyzing blood samples, officials said.

The technique could eventually prove helpful in easing public food safety fears raised by the Fukushima nuclear disaster, the officials said Saturday.

At the moment, all testing is performed only after the animals have been slaughtered, and only on some of the meat, raising doubts over the reliability and sanitation of the testing regimen, and problems for cattle producers and meat processors alike.

Although all cattle raised within 30 km of the Fukushima No. 1 power plant and in other designated areas are subject to radiation tests at local slaughterhouses, farms in other parts can ship all their cattle out as long as one animal per farm passes the test.

In some cases, slaughterhouses in other prefectures are refusing to accept Fukushima cattle because of concerns that the screening process isn't stringent enough.

To dispel those concerns, the Fukushima Prefectural Government is trying to determine how amounts of radioactive matter in blood and meat are related.

The process involves taking about 100 milliliters of blood and samples of meat from about 30 beef cattle — many raised on farms in the hot zone around the crisis-hit power plant — and measuring any evidence of radioactivity using a germanium semiconductor detector.


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