2. The worst man made disaster in
human history .It is one of only
two classified as a level 7 event
(the maximum classification) on
the International Nuclear Event
Scale
2
4. Chernobyl 4
• Chernobyl power plant
was built in an area of
wooded marshlands in
northern Ukraine in
1978-1979
• Ukraine already held
10% of the worlds
nuclear power
production when the
Chernobyl nuclear
power-station was built.
6. April 26, 1986:
Chernobyl nuclear power plant
Operator errors cause a reactor
explosion
Explosion releases 190 tons of
radioactive gasses into the
atmosphere
People:
7 million lived in contaminated
areas; 3 million were children
Wind:
Carries radiation far distances
of Facts
6
9. An Experiment
Engineers working at Chernobyl's
number four reactor did a test on the
evening of April 25, 1986.
The experiment was to see whether the
pumps cooling system could still run
using power generated from the
reactor under low power if the
auxiliary electricity supply failed.
9
10. The Experiment Begins
10
At 11pm at night on April 25,
the control rods which are
used to regulate the fission
process in a nuclear reactor
were lowered. The fission
process being the process
used to absorb neutrons thus
slowing the initial chain
reaction. When the engineers
lowered the rods it reduced
the output of the reactor by
20% of the normal output
required for a test.
11. 11
A Problem Begins
When the Engineers lowered the control
rods they lowered too many, making the
output drop too quickly, causing an almost
complete shutdown of the reactor.
12. 12
The Problem Worsens
The output dropped so
quickly that the safety
systems were disabled. The
Engineers were concerned
about possible instability,
so they began to raise the
rods in hope of increasing
output.
At 12.30am in the morning
on April 26, they decided
to continue.
13. Trying To Raise Output
By 1am in the morning of April 26,
the power of the reactor was
only about 7%, so the engineers
raised more rods to raise the
power. The engineers disabled
the reactor's automatic
shutdown system to allow the
reactor to work under low power
conditions.
13
14. Too High :Overload
Control rods were again raised by
engineers to increase power. By
1.23am in the morning of April 26, the
power reached 12% and the decision
was made to carry on with the
experiment. Only after a few seconds
though, the power levels suddenly
surged to dangerous levels.
14
15. Overheating Begins
This caused the reactor to
overheat the water in the
cooling system started to
steam. At this point there
were only six control rods
remained in the reactor
core, the minimum safe
operating number was thirty.
15
16. Boom
At one twenty-four on the morning
of April 26, the first two explosions
occurred and caused the reactor's
roof to blow off and the content to
erupt out. The roof being blown off
caused air to get into the reactor
and ignite the carbon monoxide
gas causing a reactor fire. The
reactor fire burned for nine days.
16
18. What caused the disaster
18
There were two official
explanations of the accident
•later acknowledged to be
erroneous, was published in August
1986 and effectively placed the
blame on the power plant
operators.
•The second report published in
1992 was less critical of the
operators and placed much
greater emphasis on the design of
the reactor itself.
19. 27 April, 1986: The
first photo to be
taken of the
reactor, at 4pm, 14
hours after the
explosion. This was
taken from the first
helicopter to fly over
there.
19
21. 21
70% of the radioactive material70% of the radioactive material
was blown into the neighboringwas blown into the neighboring
country of Belarus.country of Belarus.
23. 23
In all 150,000In all 150,000
squaresquare
kilometres inkilometres in
Belarus,Belarus,
Russia andRussia and
Ukraine wereUkraine were
contaminated.contaminated.
24. Exclusion zone
Chernobyl Nuclear Power Plant
Exclusion Zone-also known as the Zone
of Alienation
Prypiat- abandoned city
Chernobyl (city)-semi-abandoned city
Kopachi- abandoned village
Poliske- abandoned town
Red Forest
24
25. 25
• “Liquidators”
– These were firemen who helped
put out the fires and helped clean
up the radiation
– Most did not realize the dangers
of radiation.
– Many later died from radiation,
because they didn’t wear
protection.
– An estimated 8,000-20,000 to
date have died (20% from
suicide)
• Robots
– United States supplied
– Specifically designed to enter
reactor core and help build the
sarcophagus
The Clean Up
27. Direct Casualties
5.5 million people still live in
contaminated areas
31 people died in 3 months of
radiation poisoning
134 emergency workers
suffered from acute radiation
sickness
25,000 rescue workers died
since then of diseases caused
by radiation
Cancer afflicts many others
Increased birth defects,
miscarriages, and stillbirths
27
28. Indirect Casualties
By the year 2000 there were
1800 case of thyroid cancer
in children and adolescent
100% increase in the
incidence of cancer and
leukemia
High number of suicide and
violent death among
Firemen, policemen, and
other recovery workers
28
30. Mutation
30
Mutations in both humans and
other animals increased
following the disaster. On farms
in Narodychi Raion of Ukraine,
for instance, in the first four
years of the disaster nearly 350
animals were born with gross
deformities
Piglet with dipyguson exhibit at
the Ukrainian National Chornobyl Museum
31. Environment Impact
Areas still impacted
today:
Soil
Ground Water
Air
Food
Crops
Livestock
31
34. Now Moose, deer,
boar, wolves, and
bears have been
reported in the
area, breeding in
large numbers.
Scientists have
been unable to
detect any large-
scale mutations.
Safe from fishing
rods, these giant
catfish swim in the
radioactive water
river near the
reactor
34
35. Chernobyl New Safe Confinement
35
The primary goal of the
NSC is to prevent the
reactor complex from
leaking radioactive
material into the
environment and the
secondary goal is to
allow a future partial
demolition of the old
structure.
37. 37
Chernobyl Memorials
A memorial to the firefighters
who died after trying to stop the
fires that engulfed the plant.
They weren’t even told there was
radioactivity.
A memorial to all of those who died
at Chernobyl
