1. 1. CHERNOBYL TRAGEDY THE WORST NUCLEAR POWER ACCIDENT IN THE HISTORY.
2. 2. WHAT??
   • On April 1986,reactor number 4of the Chernobyl plantexplodedreleasing plumes of highly radioactive fallout into the atmosphere and over an extensive geographical area.
   • WorstNUCLEAR POWER plantdisaster everand the onlylevel 7instance on the INTERNATIONAL NUCLEAR EVENT SCALE.
   • Fallout400 times than that had been in Hiroshima .
   • Statistics reveal56 direct deaths , and about4000 extra cancer deathsamong about6,00,000 contaminated ones .
   • Resulted inevacuation and resettlement of over 4 lakh people .
   • With estimatedcost of 200 billion USD . It iscostliest tragedyin modern history.
3. 3. WHERE??
   • Chernobyl at the time of accident was under former USSR.
   • Now its in Ukraine. Located to north of Kiev and near town of Pipriyat.
   • Ukraine and Belarus were the most affected countries by the explosion.
4. 4.
   • Station had4 RBMK 1000 plant . With first one commissioned in 1977, and fourth in 1983.
   • Each produced1 GW of electricitycontributed 10% of Ukraines power supply.
   • Plants 5 & 6 were under construction.
   • On April 26, 1986.Plant 4 was running at low power . As it neared its end of fuel cycle. Was to be shut down for maintenance.
   • ATest was proposed to check performance of generator , which supplied when main power will be off. Called Power blackout experiment.
   • Reactors design was unstable at low power , and operators werereckless about safety precautions.
   • Animportant safety device was avoidedduring station building due to financial reasons. Plant worked2 years without it . Operatorsdesperateto carry out the test
   • Experiment wasperformed at the most dangerous point in reactor cycle .
   BRIEF OUTLINE
5. 5. The REACTOR
   • Uranium Rods: by fission produced 3200 MW thermal energy.
   • Heat SteamRun Turbineelectricity.
   • Control Rods. And Graphite rods. Moderate the reactn.
   • Unusual accumulation of steam around Uranium rods may lead to uncontrollable fission.
6. 6. Exactly What Happened
   • Inexperienced crew.
   • Blackout operation started.
   • Reactor unstable below 700MW.
   • Operator mistake or system failure lead reactor power suddenly drop to 30MW.
   • Shocked crew took out whole control rod, violating safety procedures.
   • Regained to 200MW. Manual taking over of cooling systems.
   • Shut down warning systems to continue the test.
   • Steam started forming near rods. Operators Unaware.
   ON APRIL 26 1986.
7. 7. Exactly What Happened
   • Operators continue test.
   • Steam continue to build up inside reactor core. Increasing Power
   • 700MW900 MW2000MW OUT OF CONTROL.
   • Following safety shutdown procedure, control rods fully inserted.
   • But graphite tips increased the fission. Power now 10000MW. 100 times more.
   • BOOM, power lids blown off by steam from bottom of reactor.
   • Air entered the core, mixed up with the reactants. IInd bigger explosion
   • BOOM.
   BOOM!!!
8. 8. CRISIS
   • Radiation level hit off to5000r per second.
   • Theconditions were overlooked , operators and fire fighters continued to put off fire without any masks, not being aware.Many of them died within a week.
   • To reduce emissions, the teambombarded the reactor with 5,000 metric tons of shielding materialconsisting of lead, boron, sand, and clay. It took 3 weeks.
   • Emissions included Cs-17, I-131, Sr-90 and other radio nucleotides.
   • Wind carried this to other geographic regions.
   • 2 died and 52 hospitalized within 24 hours. High radioactive presence in air remains a concern.
   An ejected Graphite from Core
9. 9. CRISIS
   • Chernobyl and Pipriyat were immediately evacuated.
   • Evacuation of Belarus and other parts carried out in stages.
   • About4 lakh peoplehad to be resettled.
   • Estimated100 died within 3 months .
   • Secretive USSR tried to cover up the facts, and show the world everything was normal.
   • Chernobyl was completely sealed.
   Chernobyl Arial view right after the incident. Evacuation of Pipriyat. Inside the plant
10. 10. The SARCOPHAGUS
    • Aconcrete containment buildingor a protective box called sarcophagus was placed over the wrecked reactor.
    • This was toprevent the additional radioactive materials from escaping .
    • 200 tones of radioactive material lie deep within it.
    • The plant after isolating from the 4 threactor continued to work due to insufficient power generation.
    • But by intervention of IAEA and G-7 countries,the plant was shut down by 2000 .
    • However after this much years, the outside of sarcophagus is appearing to be degrading.
    • Anew sarcophagusor NSCwill be installed around the reactor by 2011 , which will be thelargest movable structure ever built.
11. 11. VICTIMS NOT SURVIVORS LIVING WITH THE RADIATIONS. One described.. experience of the radiation as"tasting like metal",andfeeling a sensation similar to pins and needles all over his face. At leastone type of cancerattributed to Chernobyl. Thyroid Cancer increasedfour foldsfrom 1986, with children the most affected.
12. 12. AFTERMATH
    • Evidence of leakage was first found by Sweden, and then so on. Lastly USSR had toadmit.
    • Pipriyatriver badly affected . Pine forest covering the area turned brown and died. It was then calledRed Forest
    • 20% farmlands of Belarus completely removed from production.
    • MadeUSSR less secretive . Became more open society.
    • Luckily thecontamination were not genetic and the next generation were not affected.
    • Evacuated area: ahaven for wildlife . New species found due to absence of humans.
    MEMORIAL BUILT NEAR THE REACTOR
13. 13. GHOST TOWN OF PIPRIYAT Boards showing signs of now extinct towns ANOTHER MEMORIAL
14. 14. 20 YEARS HENCE
15. 15. On Soviet
    • Potentially unstable reactor design. + Incompetent operators + Irresponsible management .
    • Resulted into that horrific explosion On that April night of 1986.
    • A book by Gregory MedvedevThe truth about Chernobyltells aboutsecretive, authoritarianSoviet bureaucracy.
    • Chose cheapness over safety. Promoted Incompetent personals.
    • Soviets policy engineered the tragedy.
    A RECENT PICTURE OF THE REACTOR
16. 16. LAST WORDS
    • GREAT POWER COMES WITH GREAT RESPONSIBILITIES.
    • Power should be used for Human Development than Economic Development.
    • Nuclear Energy although produces large amount of electricity, it is a high risk substance.
    • Hence it should be dealt by highly responsible people.
    • Judicious and specific use.