2. Nuclear Disaster
By International Atomic Energy Agency (IAEA), The
Nuclear disaster is "an event that has led to significant
consequences to people, the environment or the
facility”.
The major Nuclear disaster is one in which the
reactor core is damaged and amount of radioactivity
are released such as Chernobyl Disaster.
4. CONTD
The Chernobyl disaster was a nuclear reactor
accident in the Chernobyl Nuclear Power Plant in
the Ukraine, which used to be a part of the Soviet
Union.
It is considered to be the worst nuclear power
plant disaster in history and the only level 7
instance on the International Nuclear Event Scale.
5. CONTD In Northern
Ukraine
10 miles away
from Belarus
80 miles North
of Kiev
7. CONTD
Located 11 miles north of the city of Chernobyl
Plant consisted of 4 reactors
Produced 10% of Ukraine’s electricity
Construction began in the 1970’s
Reactor #4 was completed in 1983
At the time of the accident, reactors #5 and #6 were
in progress.
9. Flawed operating explanation
Having a mistake or weakness
Ignorant of safety requirement
Lack of experience and training
Insufficient communication
Overconfident : only normal electrical
test
Choosing cheapness over safety
10. Second factor is the operators were not
informed about problems with the
reactor.
The designers knew that the reactor was
dangerous in some conditions but
intentionally concealed this information.
The Chernobyl accident in 1986 was the
result of a flawed reactor design that
was operated with inadequately trained
personnel and without proper regard for
safety
Apart from that the two official
explanations, the causes of the accident
is say to be cause by the poor design of
the plant.
11. Poor Design of Plant
Partial containment was bypassed
and went out on the top of reactor
core.
Hot fuel and graphite were exposed
to air
Cesium and radioactive Iodine
12. Sequence of events
Excessive insertion of control rods
Excessive removal of control rods even more
than the operating levels
Commencement of the test at low levels of
power generation
Excessive water flow rate used
Experiment started
Rise in temperature
13. CONTD
SCRAM started
Displacement of coolant due to control rods
Excessive temperature
Fracture of fuel rods
Control rods stuck
Reactor thermal output 30 GW (10 times
normal)
14. CONTD
Sudden increase in steam pressure
Bursting of cooling water pipes
Reactor Lid blown off
Explosion of either hydrogen or the
graphite
15. Day of disaster
25 April 1986
01:00 The preparation for the test
13:47 Lowering of the reactor power halted at 1,600
MWt
14:00 The ECCS was isolated
23:10 The power reduction resumed
16. 26 April 1986
24:00 Operation shift change
24:28 Power level is now 500 MWt and kept
decreasing to 30 MWt
24:40 The operator withdrew some control rods
01:00 Power had risen to 200 MWt
01:03 Connecting the fourth main cooling pump to
the left loop of the system 200 MWt
01:07 Connecting the fourth main cooling pump to
the right of the loop system - this was a violation of
NOP
17. 26 April 1986 (cont.)
01:19 Increased feed water flow to the steam
drums and removed more control rods -violation
of NOP
01:23 The test was started
01:23:10 Automatic rods withdrawn from the core
01:23:21 Two groups of automated control rods
were back to the core.
18. 26 April 1986 (cont.)
01:23:30 Power kept increasing
01:23:40 Emergency button pushed
01:23:44 Power is at 300000 MWth
01:23:48 1st thermal explosion
01:23:55 2nd explosion
19.
20. (a) International Spread of Radioactivity
The explosion at Chernobyl acted like a
volcano, blowing radioactive particles far
into the sky.
Wind moved the plume, or cloud of
radioactive particles, all around the world.
Even worse, when the plume passed by
several countries, it began to rain, and
nuclear fallout hit the ground.
Large areas of Belarus, Ukraine, Russia and
beyond were contaminated in varying
degrees.
21. (b) Health of People
According to Ukrainian health ministry
officials, 125,000 people have died as a
result of the accident, and more deaths are
expected.
Two people died in the initial steam explosion,
but most deaths from the accident were attributed
to radiation.
Over 300,000 people were moved because of
the accident.
An increase of thyroid cancer has been
diagnosed among children in areas of
Belarus, Ukraine and Russia.
Some believe the stress of the accident has
been worse on people than the radiation.
22. (c) Delayed Health Effects
One of the most delayed effects of the
radiation is the induction of cancer.
For example: Solid cancers among Russian
liquidators whom exposed to more than 150
mSv.
The people in the area of contamination have
suffered a paralyzing fatalism.
Man and young boy
operated for thyroid
cancer after Chernobyl
nuclear accident.
23. The Children of Belarus
Children were much more affected by Chernobyl and
the radiation, due to their weaker immune systems.
1991-1992--sickness rate among children almost
tripled
Threat to gene pool—fewer children being born.
The following problems have increased in Belarusian
children:
heart and circulatory diseases, malignant tumors,
and disorders of the nervous system, sensory
organs, of the bone, muscle and connective tissue
system.
24. Children Contd
It is estimated that 1 out of every 4 infants in Belarus
will develop thyroid abnormalities.
The normal rate of thyroid cancer would be only one
in 1 million.
Normally, this is a rare disease, with only 1 case per
year being reported in Belarus before the Chernobyl
accident.
Thyroid cancer can take 10-30 years to show it’s
effects.
25. Children Contd
Normally, this is a rare disease, with
only 1 case per year being reported in
Belarus before the Chernobyl accident.
Thyroid cancer can take 10-30 years to
show it’s effects.
There has been a 2,400% increase in
the rates of thyroid cancer in Belarus
since 1986.
26. The topic of the children of Chernobyl is most shocking and awful.
The increase in leukemia is even worse where there are dozens of
cases of leukemia among the children.
An increase of thyroid cancer has been diagnosed among children in
areas of Belarus, Ukraine and Russia.
These children have to take painful procedures every day to
postpone the fatal moment.
By year 2000, about 4000 cases of thyroid cancer had been
diagnosed in exposed children.
Mutation in newly born children
27. Flora and fauna
(i)Flora
After the disaster, four square kilometres of pine forest in
the immediate vicinity of the reactor turned ginger brown
and died, earning the name of the “Red Forest”
Local pine trees grow huge pine cones, pine needles of the
needle-like leaves 10 times heavier than normal.
Some fruits and vegetables also affect which causes the
oddly shaped of potato, tomato and so on.
28. Flora and
fauna
(ii) Fauna
Radiation has affected animals living near the site
of Ukraine's Chernobyl nuclear disaster.
A major effect on the livestock was mutation.
The livestock was culled and buried.
Figure above: These animals suffering
from a serious effect of mutation
Figure above: A cow that
experiencing mutations. This
co having a cleft lip.
29. Economically
In the 1986 to 1989 industrial and agricultural losses and
insurance payments total about US$36 Billion spent during
this period
The total costs including cleanup, resettlement, and
compensation to victims has been estimated to be roughly
US$200 Billion.
The accident, about US$400 Million was spent on
improvements to the remaining reactors at Chernobyl,
considerably enhancing their safety.
30. CONTD
Between 300,000 and 600,000 people were
brought in to clean-up.
Belarus lost 1/5 of its farming lands(700
million dollars a year loss.)
350 industries were lost due to the disaster.