Criticality Incident

[Philip Hypes <phypes@lanl.gov>]

Here's the Associated Press article about the incident, taken from ABC.com.
 Interesting that this article refers to the incident as a "leak", and does
not mention criticality.

The Associated Press
 T O K Y O, Sept. 30 — Three workers were hospitalized and local schools
were ordered to keep their students indoors today after a radiation leak at
a uranium processing facility in northeast Japan. 
   The workers were taken to a local hospital, where two of the three were
nauseous and had diarrhea, said hospital spokesman Masaru Ogura. They were
then flown by helicopter to a medical center specializing in radiation
sickness. 
   About 150 people living within a 350-yard radius of the accident in
Tokaimura, a town about 70 miles northeast of Tokyo, were being evacuated
to a nearby community center, said town official Eiko Onuma.
   Police declared off-limits an area nearly 2 miles around the plant after
radiation levels 10,000 times higher than normal were detected. 
   Ibaraki prefectural police spokesman Yasuo Hasuda identified the three
workers as Hisashi Ouchi, 35, Masato Shinohara, 29, and Yutaka Yokokawa, 54. 

Visions of a ‘Blue Glow’ 
    The leak was detected at 10:35 a.m. Its cause was not immediately
known, but police denied reports that a fire had broken out. 
    A 200-yard area inside the site was sealed off, said Yukio Mimura, an
official for the local government in Ibaraki prefecture (state). Several
hours later, police were still keeping all traffic out of the area. The
sickened workers said they saw a blue glow before becoming ill, said Makoto
Ujihara, head of the Tokyo office of JCO, Co., the private company that
operates the plant. He said other details were not clear. 
    Ujihara said the plant reprocesses uranium for nuclear fuel. 
    Warnings to residents were broadcast over the town’s loudspeaker
system, and nearby schools were instructed to close their windows and keep
their students inside, said Toru Hizawa, a town official. 

Accidents Happen 
    Radiation levels around the leak were 10,000 times higher than normal,
and at a distance of about one mile from the accident about 10 times
normal, said Tatsuo Shimada, an Ibaraki official. 
    Shimada said the radioactivity in areas around the facility had
returned to normal, but it was still high at the site of the leak. 
    Accidents have plagued the Japanese nuclear power industry, undermining
public faith in the security of the nation’s atomic plants. 
    In 1997, a fire and subsequent explosion at the Tokaimura plant exposed
37 workers to low levels of radiation. 
    In July, radiation at 11,500 times above the safety limit leaked out of
a cracked pipe in a plant in Tsuruga, 200 miles west of Tokyo. Officials
said no radiation was released into the atmosphere. 
    Japan, a nation poor in natural resources, relies on nuclear power for
about one-third of its electricity. 


___________________________________________________________
Philip Hypes
Los Alamos National Laboratory
Safeguards Science and Technology Group (NIS 5)
(505) 667-1556  phypes@lanl.gov

Opinions expressed are purely my own unless otherwise noted

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