Saad FarooqiSaad FarooqiBS-Environmental SciencesBS-Environmental Sciences55thth Semester SemesterDeptt of Environmental And Deptt of Environmental And Conservation SciencesConservation SciencesUniversity of SwatUniversity of Swat

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.

BackgroundChernobyl disaster  April 26, 1986

CONTDThe 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. 

CONTD In Northern Ukraine

10 miles away from Belarus

80 miles North of Kiev

CONTD

CONTDLocated 11 miles north of the city of ChernobylPlant consisted of 4 reactorsProduced 10% of Ukraine’s electricityConstruction began in the 1970’sReactor #4 was completed in 1983At the time of the accident, reactors #5 and #6 were 

in progress.

Cause of Chernobyl

Flawed operating explanation

Having a mistake or weaknessIgnorant of safety requirementLack of experience and trainingInsufficient communicationOverconfident : only normal electrical

test Choosing cheapness over safety

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.

Poor Design of Plant

Partial containment was bypassed and went out on the top of reactor core.Hot fuel and graphite were exposed

to airCesium and radioactive Iodine

Sequence of eventsExcessive insertion of control rodsExcessive removal of control rods even more

than the operating levelsCommencement of the test at low levels of

power generationExcessive water flow rate usedExperiment startedRise in temperature

CONTDSCRAM startedDisplacement of coolant due to control rodsExcessive temperatureFracture of fuel rodsControl rods stuckReactor thermal output 30 GW (10 times

normal)

CONTDSudden increase in steam pressure

Bursting of cooling water pipes

Reactor Lid blown off

Explosion of either hydrogen or the

graphite

Day of disaster25 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

26 April 198624:00 Operation shift change24:28 Power level is now 500 MWt and kept

decreasing to 30 MWt24:40 The operator withdrew some control rods 01:00 Power had risen to 200 MWt01:03 Connecting the fourth main cooling pump to

the left loop of the system 200 MWt01:07 Connecting the fourth main cooling pump to

the right of the loop system - this was a violation of NOP

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 started01:23:10 Automatic rods withdrawn from the core01:23:21 Two groups of automated control rods

were back to the core.

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

(a) International Spread of RadioactivityThe 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.

(b) Health of PeopleAccording 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.

(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.

The Children of BelarusChildren were much more affected by Chernobyl and

the radiation, due to their weaker immune systems.1991-1992--sickness rate among children almost

tripledThreat 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.

Children ContdIt 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.

Children ContdNormally, 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.

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

Flora and fauna(i)FloraAfter 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.

Flora and fauna

(ii) FaunaRadiation 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.

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.

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.

Some Picture of the Disaster