TOPICS
[
UP
] [ Serious nuclear accident occurred
in Tokai ] [ Operation
of Rokkasho Reprocessing Plant Delayed Once Again ] [
Review
of Long-term Program on Nuclear Energy Begins ] [ Electric
Utility Industry Law Amended ] [ Primary
coolant water leakage shut downs Tsuruga 2 ] [ The
Fourth Shipment of HLW ] [ Current
Situation in Japanese Nuclear Industries ] [ 20
Reactors - Unlikely to Succeed ] [ Uncertain
Future for Deregulation ] [ New
Series of Roundtable Talks ] [ Petition
to Cancel the Approval of Design for Casks ] [ Aomori
Allows Spent Fuel Shipment ] [ Jabiluka
Mining ] [ Nuclear
Power is No Future Energy ]
Report [2] 10/2/99 21:00
(1) Conduct a thorough research and release complete
data on the findings of the released radioactivity!
There has been a very limited amount of data given regarding the radioactivity
released. However, CNIC has done a provisional trial calculation on the
amount of uranium that reacted, and the amount of radioactivity released.
| Of the uranium in the precipitation basin that caused the criticality
accident, we assume that roughly 1-10grams of uranium 235 underwent fission,
and 1016 to 1017 Bq (becquerel) of fission products
were produced. (When assumed that the radioactive materials released at
Chernobuyl was roughly 1019 Bq, this estimated amount is 1/1000
to a couple hundredth of one. This amount is based on very limited information,
thus we apologize for the possibility of the numbers entailing some inaccuracy.
)
When it is assumed that 1/100 of the produced 1016 to 1017
Bq fission materials (radioactive materials) were released, based on the
assumption that all the radioactive gas was released and some of the other
radioactive materials were released as well, the amount of radioactive
materials released was 1014 to 1015 Bq, i.e. one
hundred to one thousand teraBq. According to IAEA International Nuclear
Event Scale, an accident involving a release of hundreds to thousands teraBq
radioactivity is categorized as level 5. STA announced that this accident
was level 4, however, in reality it is a level 5 accident.
We assume that an amount of radioactive materials corresponding to the
amount produced in the facility were released to the outside of the facility,
and that the radioactive materials with short halflives have already attenuated.
However, it is certain that no small amount of radioactive materials are
still left inside the precipitation basin.
It has been reported that the gamma ray emitted from the remaining radioactive
materials are kept inside because of a shelter consisting of layers of
aluminum was put around the facility. However, this shelter is an unreliable
tentative treatment, and there are serious doubts for its sufficiency.
There is a possibility that some of the remaining radioactive materials
are still being released at the moment, and the possibility of such materials
being released in the future cannot be denied as well. |
At 10/2/99 6:30 p.m. a "Declaration of Safety" was issued by the government
saying that the area 350meters radius of the site has no contamination
and thus they would call off the evacuation request. However, judging from
the conditions supposed above, we do not beleive that the government has
sufficient enough facts to release such a declaration.
In addition, the exposure check done for the area residents who request
such an examination is only checking if the surface of their body is contaminated
by radioactive materials, and is not a check for previous exposure (internal
and other exposure by neutron rays, gamma rays, and radioactive materials
) from the accident. Thus this examination cannot determine whether a person
has been exposed or not.
(2) The realities of the exposure is not known yet.
It is said that the 49 workers and area residents have been exposed. However,
this is not a number based on examinations for various types of exposure.
The examination was conducted to detect exposure by neutrons, and thus
relates only to the number of people who had sodium24, that is produced
by neutron exposure, in their body.
Thus there has not been an investigation on exposure by gamma-ray and
internal exposure by inhalation of radioactive materials. There are good
reasons to believe that a much higher number of people have been exposed.
There must be an all inclusive investigation and a complete release of
the findings.
In the early morning of 10/1/99, workers went to the space underneath
the floor of the accident site to extract coolant water in order to contain
the criticality reaction. Due to that operation, 18 people were exposed
to an amount of 20mSv to 103mSv. It is regulated by law that the annual
dose limit for workers are 50mSv/y, and 100mSv for one operation during
emergencies. However, many workers were exposed to an amount beyond the
regulated annual dose limit, and one of them was even exposed to an amount
beyond the emergency limit. There should be a system that does not involve
such exposure to the workers. JCA and the Science Technology Agency (STA)
are greatly responsible for bring on such exposure to the workers. There
must be a detailed data for exposure.
(3) An absent of criticality control measures brought
about this accident.
According to "Basic Guidelines for the Licensing of Nuclear Facilities"
put to effect in 2/7/1980, it is stated that for all facilities dealing
with nuclear fuel materials, "there must be a counter measure set up to
prevent criticality reaction under all possible scientifically conceivable
conditions." If this policy was pursued, all installations of the facilities
must be designed to prevent criticality even in a case of human error (i.e.
the facilities must be designed with criticality prevention installment).
Criticality control by the amount and density of nuclear materials can
cause criticality by human errors. However, there were no installation
for criticality control in the precipitation basin where the reaction took
place.
In addition, the guideline requires that "there must be a proper counter
measure set up for in case of a criticality accident." However, no sufficient
measures could be taken to stop this criticality, and it was left alone.
Furthermore, there was no neutron detection system in the plant to detect
criticality. These facts are clearly in violation of the guideline. The
company that designed such an illegal facility, and the STA that licensed
the facility hold great responsibility. The cause of this accident cannot
be explained away as human error.
There are many facilities with units that do not have criticality prevention
installment. This accident has made it clear that such facilities must
be fit with criticality prevention installment. All facilities including
JCO must be reassessed under renewed licensing review for the safety and
the location of the sites to prevent any type of damage to the area residents,
even in a case of a worst criticality accident.
Report [1](10/1/1999 3:45 p.m.)
Accident is not over
In regards to the accident first detected in the afternoon of 9/30/99,
it has been reported that the criticality condition had ceased after the
coolant extraction was completed early this morning (10/1/99). However,
we do not believe that the accident is over.
Although the criticality condition has ceased, the radioactive materials
are still being released into the atmosphere, and CNIC thinks that this
condition will continue yet for a while.
Furthermore, effective measures have not been taken to respond to the
above condition. It seems necessary to remain fully cautious of the situation.
CNIC's Statement on the Criticality Accident at
Tokai
There has been a criticality accident at JCO Ltd. Tokai site. Three workers
were hospitalized for acute radiation injury. A large amount of radioactivity
released into the atmosphere and a radiation amount 16000 times normal
amount was measured. Thirty-nine households (150 people) were evacuated
and 200m radius of the site was declared off-limits. The roads in the 3km
radius of the site were closed and residents within 10 km radius of the
site were advised to stay indoors. A criticality accident of this nature
at a Japanese nuclear facility has never occurred before, and the situation
is serious. The nuclear industry, the Science and Technology Agency (STA),
and the overseeing governmental offices that allowed this serious accident
face grave responsibility.
CNIC demands an absolutely thorough investigation, and demands that
the plant be shut down. We also demand a full inspection of the safety
measures system and a review of the existing safety inspection system.
Furthermore, any other facilities without adequate safety measures to respond
to a criticality accident should be shut down immediately.
It has been reported that the criticality explosion accident happened
during a refining process for highly-enriched uranium for the fast breeder
test reactor, Joyo. Sixteen kg of highly-enriched uranium was filled into
a settling basin designed for no more than 2.4 kg, an amount almost 6.5
times more than it should have been.
For such act to take place, there must have been a serious flaw in the
criticality control or the criticality control system of the plant itself
had been insufficient. Furthermore, twelve hours after the accident at
the time of this press release, the criticality explosion has not yet ceased,
and the radioactive count is still high in the vicinity of the site. Sufficient
action has not been taken in response to the accident or to isolate the
site. We find the following points problematic: the structure and the sealed
nature of the site; the fact that a plant dealing with highly-enriched
uranium was built adjacent to a residential area of ordinary citizens;
and that the safety regulations were far looser for this plant compared
to nuclear power plants.
This accident has proved that the existing criteria for the location
of the site and safety regulation systems that disregard the dangers of
nuclear material are significantly flawed. In addition, the delay in notifying
local government and the residents, and the lack of sufficient information
concerning this accident has brought to light the inability of the nuclear
industry and the STA to sufficiently respond to an emergency. Even at an
area like Tokai village where there are a number of nuclear facilities
including nuclear power plant, it took one hour for the accident to be
reported, and not even the evacuees were given accurate information on
the matter. In view of these facts, we assert that the company and the
STA that cannot even grasp an accurate situation of the accident are not
capable of handling nuclear materials. By denying the possibility of the
criticality accident, and neglecting to secure the safety of local residents
, the nuclear industry and the STA have indirectly allowed this criticality
combustion accident to happen. This fact should not be taken lightly and
the responsibility of company and the STA is grave.
This accident has brought to light the dissembling nature of the Japanese
governmentís nuclear policy that has been concealing the danger of nuclear
utilization with the myth of the safety of nuclear energy. CNIC strongly
calls on the state, STA, Ministry of Trade and Industry, to openly lay
out the dangers and problems of nuclear energy utilization and to scrutinize
the propriety of current nuclear energy policies.
An English translation of the statement issued at 1:30
a.m. 10/1/99
Serious nuclear accident occurred in Tokai
30 September 1999
The nuclear accident at a test facility in the JCO Ltd.'s uranium processing
plant, Tokai took place in 10:35 am Japanese Standard Time (+900) on 30
SEP 99.
Initially an atmospheric radiation count of 0.84 mSv/hour (4000 times
of the annual limits of intake) was monitored, but the local government
says now the count is back to normal. A criticality accident is suspected.
Three workers were exposed because of the accident, and the exposed
workers taken to the hospital were then transferred by helicopter to the
Science and Technology Agency's radiological center in order to treat the
acute radiation injuries. One of the three is reported to be in a critical
condition.
The facility in which the accident occurred is a commercial plant where
enriched UF6 gas is converted to UO2 powder for further processing. The
pellet fabrication is to be done in another plant nearby.
Police has declared a provisional 200m radius off-limit zone, around
the site. People are told to shut all the windows and not to go outside.
The cause and details of the accident has not yet been disclosed.
Worst Ever Accident Within Japan at Tokai, Ibaraki
Information Part 1
30 September 1999
There was a nuclear accident at a test facility in the JCO Ltd.'s uranium
processing plant located in Tokai, Ibaraki. It happened at 10:35 am Japanese
Standard Time (+900) on 30 September, 1999.
Initially, an atmospheric radiation count of 0.84 mSv/hour (10,000 times
of the annual dose limit) was monitored, but the local government has announced
that the radiation count is back to normal. The Science and Technology
Agency (STA) has announced that it was a criticality accident.
Three workers were exposed because of the accident, and the exposed
workers taken to a local hospital were later transferred by a helicopter
to the National Institute of Radiological Sciences in Chiba City, east
of Tokyo, in order to treat the acute radiation injuries. They seem to
have inhaled high concentration uranium gas. Two of the three exposed workers
are reported to be in a critical condition.
The facility in which the accident occurred is a commercial plant where
enriched UF6 gas is converted into UO2 powder for further processing. The
pellet fabrication is done in another plant nearby.
Police has declared the area of 200m radius of the site to be an off-limit
zone. The local government (Tokai-mura administration) issued an evacuation
request to the residents of the surrounding 350m radius of the site. All
the villagers residing outside the 350m radius were asked to stay indoors.
School children are ordered not to go home, but remain indoors at each
school. Naka-machi, a town next to Tokai mura, also advised the residents
to remain indoors.
The cause and details of the accident has not yet been disclosed. CNIC
will release a statement as soon as enough materials are collected, however,
we will keep people post on any further details gathered.
Tokai accident information, part 2
According to T.V. news around 6 p.m., the head of Tokai village stressed
three points at a press conference.
1) The atmospheric radiation count has not decreased around the site.
2) There is a possibility that nuclear fission is still occurring at
the moment.
3) The plant's structure is intact.
Tokai accident information part 3
The radiation count is still high and not even JCO workers can enter
the site. No one is aware of the situation inside the plant and nothing
is being done. Thus it is very likely that the criticality condition is
still in progress.
Latest news as of 9 p.m.
1) Ibaraki prefecture has advised the residents of 10km radius of the
plant to stay indoors.
2) Government has set up a committee head by Obuchi prime minister
to respond to the situation. The cabinet organization will be put off for
the moment to fully cope with this situation.
3) Atmospheric radiation count was 0.7milisievert per hour (mSv/h)
at 3 p.m. Normal count is 1milisievert per year (mSv/y).
4) Two of the three workers hospitalized are suspected to have been
seriously exposed due to a sudden increase of white blood corpuscle experienced
by both of them.
5) 160 people have evacuated to a community center. The evacuees will
have to spend the night at the center.
[
UP
] [ Serious nuclear accident occurred
in Tokai ] [ Operation
of Rokkasho Reprocessing Plant Delayed Once Again ] [
Review
of Long-term Program on Nuclear Energy Begins ] [ Electric
Utility Industry Law Amended ] [ Primary
coolant water leakage shut downs Tsuruga 2 ] [ The
Fourth Shipment of HLW ] [ Current
Situation in Japanese Nuclear Industries ] [ 20
Reactors - Unlikely to Succeed ] [ Uncertain
Future for Deregulation ] [ New
Series of Roundtable Talks ] [ Petition
to Cancel the Approval of Design for Casks ] [ Aomori
Allows Spent Fuel Shipment ] [ Jabiluka
Mining ] [ Nuclear
Power is No Future Energy ] |