nuclear disasters

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A nuclear accident anywhere is a nuclear accident everywhere Najmedin Meshkati Professor of Nuclear scienceA nuclear and radiation accident is defined by the International Atomic Energy Agency as "an event that has led to significant consequences to the people, the environment or the facility." Examples include lethal effects to individuals, large radioactivity release in to the environment, or reactor core melt.Technical measures need to be adopted to reduce the risk of accidents or to minimize the amount of radioactivity released to the environment.What is Nuclear Disaster ?

A nuclear disaster could take several forms . The most obvious would be a meltdown at a nuclear reactor plant . Though the plant might not explode, the result of such a disaster would very likely be the release of massive amount of radiation and radioactive material into the environment and it would take hundred years to decay to anything near safe levels . Nuclear disasters are usually associated with meltdowns.When a meltdown occurs in a reactor, the reactor "melts". That is, the temperature rises in the core so much that the fuel rods actually turn to liquid, like ice turns into water when heated. If the core continues to heat, the reactor would get so hot that the steel walls of the core would also melt. In a complete reactor meltdown, the extremely hot (about 2700 Celsius) molten uranium fuel rods would melt through the bottom of the reactor and actually sink about 50 feet into the earth beneath the power plant.

The molten uranium would react with groundwater, producing large explosions of radioactive steam and debris that would affect nearby towns and population centers.

Causes of Nuclear Disaster

In a safe nuclear reactor the condenser and the cooling tubes work efficiently and the heat applied on the uranium rods is controlled.Uranium Mining

Fuel Enrichment

Power Generation

Waste Disposal

RADIATION INCREASES multifold at each stage!Radioactive WasteGenerated at each stage - Mining, Enrichment, Power GenerationWaste from Enrichment has been used in Depleted Uranium (DU) bombs used in IraqEven 21st century science has NO ANSWER for Nuclear Waste DisposalWaste contaminates (beyond scope for inhabitation) a huge area in its vicinity for 1000s of years

What about the Environment & People?Is it Safe?Radiation Contaminates AlwaysEven if there is NO NUCLEAR ACCIDENT

Around a Uranium Mine

Around an Enrichment Facility

Around a Nuclear Plant

Around Nuclear WasteAn area of 30-35 km radius gets contaminated by nuclear radiation regularly!

homeRadiation Spares NothingImpacts Vegetation - AgricultureTrees near Jaduguda Uranium Mines have DEFORMED SEEDSAgricultural produce is bound to carry unacceptable amounts of radioactive content

Impacts AnimalsRadioactive Boars on the rise in Germany (thanks to Chernobyl)

Impacts Human Beings

homeNuclear explosions produce both immediate and delayed destructive effects. Immediate effects (blast, thermal radiation, prompt ionizing radiation) are produced and cause significant destruction within seconds or minutes of a nuclear detonation. The delayed effects (radioactive fallout and other possible environmental effects) inflict damage over an extended period ranging from hours to centuries, and can cause adverse effects in locations very distant from the site of the detonation.Consequences of nuclear disaster

Nuclear disaster can produce climate issues because the high temperatures of the nuclear fireball cause large amounts of nitrogen oxides to form from the oxygen and nitrogen in the atmosphere (very similar to what happens in combustion engines). Each megaton of yield will produce some 5000 tons of nitrogen oxides. The rising fireball of a high kiloton or megaton range warhead will carry these nitric oxides well up into the stratosphere, where they can reach the ozone layer. A series of large atmospheric explosions could significantly deplete the ozone layer.

Natural Ways to Mitigate Radiation DamageFukushima disaster caused many people to become aware of potassium iodide tablets, available from your local drug store, via outlets online, and sometimes distributed by utilities or local officials to people living near nuclear facilities experiencing problems. This stable form of iodine, which is used by the thyroid gland to produce necessary hormones for metabolism and fetal brain development can protect your thyroid gland from radioactive iodine-131. But it does not protect against any other limiting isotopes likely to be released from a nuclear event.However, these measures are not enough to completely moderate the harmful effects of a nuclear disaster. A nuclear disaster causes the depletion of the ozone layer which in turn leads to skin diseases. The only way to insure safety of people is to build robust nuclear reactors and efficient coolants.

Prevention is better than cure.Nuclear explosions can release high levels of radiation, an energy that removes electrons.

Nuclear radiation can damage DNA.

While areas around a nuclear explosion are immediately exposed, radiation can also remain in the atmosphere for decades, traveling great distances before it settles to the ground-level air or earth's surface

Disposing of one's outer clothing can remove up to 90% of radioactive material after a nuclear disaster.

The peace symbol was initially designed for the Direct Action Committee Against Nuclear War (DAC).

Facts about nuclear disaster:Cycle of Radioactive Materials

Nuclear EnergyApart from its disastrous potential, nuclear radiation is one of the most effective means of providing electricity to the country and ensuring economic development. If handled carefully, nuclear energy can be a greener alternative to other forms of energy like coal and petrol.

Proponents, such as the World Nuclear Association, the IAEA and Environmentalists for Nuclear Energy believe that nuclear power is a safe, sustainable energy source that reduces carbon emissions

People should stay inside buildings or areas far away from the nuclear plantPhones should not be used unless absolutely necessary, the lines may collapse if everybody is using phones and phone lines are very necessary for emergency equipment.There should be a ban on consumption of agricultural products or water. For example in Japan there was a ban on consumption of products from near the nuclear plant.In case of a Nuclear DisasterInternationalNuclear EventScale

ExhibitionSeveritySymptomsSomemillisievertsonlypossible long-termSeveral hundredmillisievertsNoimmediate effectPossibletemporarynauseaandslight feverBetween1 000and2 000millisievertsremarkable medicalEffectvomiting, fatigue,fever,riskof infection, cancerBetween2 000and4 000millisievertsserious medicalEffectvomiting,fever, digestive disorders, bleeding,hair loss, leukemia,othercancersBetween4 000and10 000millisievertsand

probabilitygreater than50%death, property damageneurological(dizziness,disorientation)andcancersof manytypesExcess of 10 000mSv

safeDeathSome Nuclear and Radiation accidents - 1952 - AECL Chalk River Laboratories, Chalk River, Ontario, Canada. Partial meltdown, about 10,000 Curies released. September 1957 - a plutonium fire occurred at the Rocky Flats Plant, which resulted in the contamination of Building 71 and the release of plutonium into the atmosphere, causing US $818,600 in damage.September 1957 Mayak nuclear waste storage tank explosion at Chelyabinsk. Two hundred plus fatalities, believed to be a conservative estimate; 270,000 people were exposed to dangerous radiation levels. Over thirty small communities had been removed from Soviet maps between 1958 and 1991. (INES level 6).

October 1957 - Windscale fire, UK. Fire ignites plutonium piles and contaminates surrounding dairy farms.An estimated 33 cancer deaths.1959, 1964, 1969 - Santa Susana Field Laboratory, Los Angeles, California. Partial meltdowns.July 1961 Soviet submarine K-19 accident. Eight fatalities and more than 30 people were over-exposed to radiation.1962 Radiation accident in Mexico City, four fatalities.January 1969 Lucens reactor in Switzerland undergoes partial core meltdown leading to massive radioactive contamination of a cavern.July 1979 - Church Rock Uranium Mill Spill in New Mexico, USA, when United Nuclear Corporation's uranium mill tailings disposal pond breached its dam.

March 1984 Radiation accident in Morocco, eight fatalities.[August 1985 Soviet submarine K-431 accident. Ten fatalities and 49 other people suffered radiation injuries.September 1987 Goiania accident. Four fatalities and 249 other people received serious radiation contamination.December 1990 Radiotherapy accident in Zaragoza. Eleven fatalities and 27 other patients were injured.April 1993 - accident at the Tomsk-7 Reprocessing Complex, when a tank exploded while being cleaned with nitric acid. The explosion released a cloud of radioactive gas. (INES level 4).

1996 Radiotherapy accident in Costa Rica. Thirteen fatalities and 114 other patients received an overdose of radiation.September 1999 - Criticality accident at Tokai nuclear fuel plant (Japan)February 2000 - Three deaths and ten injuries resulted in Samut Prakarn when a radiation-therapy unit was dismantled.April 2010 - Mayapuri radiological accident, India, one fatality.March 2011- Fukushima I nuclear accidents, Japan (current event).March 2011- Fukushima Daichi Power Station - radioactive discharge

Why is Nuclear Power Promoted in India?Current energy policies are designed to benefit foreign MNCsGeneral ElectricsWestinghouseArevaNewspapers admit that THEY ARE HERE FOR A $40 BN BUSINESS

homeWhy is Nuclear Power Promoted in India?Profit for MNCs who will provid