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Nuclear199

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Fallout from Chernobyl
400 million people exposed in 20 countries
Chernobyl’s political fallout
• Stimulated Gorbachev’s glasnost (openness)
• Stimulated nationalism in Ukraine, Belarus, and
other republics that lost clean-up workers.
• Growth of environmental opposition
• Questioning of the heart of technocratic power
– Soviet leaders were engineers, not lawyers
– USSR collapsed within 5 years.
Radiation and Health
• Health effects as a result of radiation exposure:
-increased likelihood of cancer
-birth defects including long limbs, brain
damage, conjoined stillborn twins
-reduced immunity
-genetic damage
8,000 deaths in 14 years
3.5 million sick,
one/third of them children
My grandmother, by Luda
Death of my life, by Marina
Chernobyl is war, by Irena
Beauty and the beast, by Helena
Nothing escapes radiation, by Irena
Chernobyl, our hell, by Eugenia
Self-portrait, by Natasha
“It Can’t Happen Here”
• U.S. reaction to Chernobyl, 1986
– Blamed on Communism, graphite reactor
• Also Soviet reaction to Three-Mile Island, 1979
– Blamed on Capitalism, pressurized-water reactor
• No technology 100% safe
– Three-Mile Island bubble almost burst
Three-Mile Island, PA 1979
Health around TMI
• In 1979, hundreds of people reported nausea,
vomiting, hair loss, and skin rashes. Many pets
were reported dead or showed signs of radiation
• Lung cancer, and leukemia rates increased 2 to 10
times in areas within 10 miles downwind
• Farmers received severe monetary losses due to
deformities in livestock and crops after the
disaster that are still occurring today.
Plants
near TMI
-lack of chlorophyll
-deformed leaf patterns
-thick, flat, hollow stems
-missing reproductive parts
-abnormally large
TMI dandelion leaf at right
Animals Nearby TMI
• Many insects
disappeared for years.
– Bumble bees,
carpenter bees, certain
type caterpillars, or
daddy-long-leg spiders
– Pheasants and hop
toads have
disappeared.
Nuclear reaction
• Chain reaction occurs when a Uranium
atom splits
• Different reactions
– Atomic Bomb in a split second
– Nuclear Power Reactor more controlled, cannot
explode like a bomb
History of nuclear power
1938– Scientists study Uranium nucleus
1941 – Manhattan Project begins
1942 – Controlled nuclear chain reaction
1945 – U.S. uses two atomic bombs on Japan
1949 – Soviets develop atomic bomb
1952 – U.S. tests hydrogen bomb
1955 – First U.S. nuclear submarine
“Atoms for Peace”
Program to justify nuclear technology
Proposals for power, canal-building, exports
First commercial power plant, Illinois 1960
Economic advantages
• The energy in one pound of highly enriched
Uranium is comparable to that of one
million gallons of gasoline.
• One million times as much energy in one
pound of Uranium as in one pound of coal.
Emissions Free
• Nuclear energy annually prevents
– 5.1 million tons of sulfur
– 2.4 million tons of nitrogen oxide
– 164 metric tons of carbon
• Nuclear often pitted against fossil fuels
– Some coal contains radioactivity
– Nuclear plants have released low-level radiation
Early knowledge of risks
• 1964 Atomic Energy Commission report
on possible reactor accident
–
–
–
–
45,000 dead
100,000 injured
$17 billion in damages
Area the size of Pennsylvania contaminated
States with nuclear power plant(s)
Nuclear power around the globe
• 17% of world’s electricity from nuclear power
– U.S. about 20% (2nd largest source)
• 431 nuclear plants in 31 countries
–
–
–
–
103 of them in the U.S.
Built none since 1970s (Wisconsin as leader).
U.S. firms have exported nukes.
Push from Bush/Cheney for new nukes.
Countries Generating Most Nuclear Power
Country
USA
France
Japan
Germany
Russia
Canada
Ukraine
United Kingdom
Sweden
South Korea
Total MW
99,784
58,493
38,875
22,657
19,843
15,755
12,679
11,720
10,002
8,170
Nuclear fuel cycle
•
•
•
•
•
•
Uranium mining and milling
Conversion and enrichment
Fuel rod fabrication
POWER REACTOR
Reprocessing, or
Radioactive waste disposal
– Low-level in commercial facilities
– High level at plants or underground repository
Front end:
Uranium mining and milling
Uranium tailings
and radon gas
Deaths of Navajo
miners since 1950s
Uranium enrichment
• U-235
– Fissionable at 3%
– Weapons grade at 90%
• U-238
– More stable
• Plutonium-239
– Created from U-238; highly radioactive
Radioactivity of plutonium
Life span of least
240,000 years
Last Ice Age glaciation
was 10,000 years ago
Neanderthal Man died out
30,000 years ago
Risks of enrichment
and fuel fabrication
• Largest industrial users of water, electricity
– Paducah, KY, Oak Ridge, TN, Portsmouth, OH
• Cancers and leukemia among workers
– Fires and mass exposure.
– Karen Silkwood at Oklahoma fabrication plant.
• Risk of theft of bomb material.
Nuclear Reactor Process
• 3% enriched Uranium pellets formed into
rods, which are formed into bundles
• Bundles submerged in water coolant inside
pressure vessel, with control rods.
• Bundles must be SUPERCRITICAL; will
overheat and melt if no control rods.
Reaction converts water to steam, which
powers steam turbine
Technology depends on operators
Other reactor accidents
(besides TMI and Chernobyl)
• 1952 Chalk River, Ontario
– Partial core meltdown
• 1957 Windscale, England
– Graphite reactor fire contaminates 200 square miles.
• 1975 Browns Ferry, Alabama
– Plant caught fire
• 1976 Lubmin, East Germany
– Near meltdown of reactor core .
• 1999 Tokaimura, Japan
– Nuclear fuel plant spewed high levels of radioactive gas
United States
Risk of terrorism
(new challenge to industry)
9/11 jet
passed near
Indian Point
Nuclear Reactor Structure
• Reactor’s pressure vessel
typically housed in 8” of steel
• 36” concrete shielding
• 45” steel reinforced concrete
Breeder reactor
“Breeds” plutonium as it operates
Uses liquid sodium metal instead of water for coolant
– Could explode if in contact with air or water
• 1966 Fermi, Michigan
– Partial meltdown nearly causes evacuation of Detroit
• 1973 Shevchenko, Russia
– Breeder caught fire and exploded
• Controversial proposals in Europe, U.S.
Reprocessing
• Separates reusable fuel from waste
– Large amounts of radioactivity released
• 1960s West Valley, NY
– Radiation leaked into Lake Ontario
• 1970s La Hague, France
– Released plutonium plumes into air
Back end: Radioactive wastes
• Low-level wastes in commercial facilities
• Spent fuel in pools or “dry casks” by plants
• Nuclear lab wastes
– Hanford wastes leaked radiation into Columbia River
• High-level underground repository
– Yucca Mountain in Nevada to 2037
– Wolf River Batholith in Wisconsin after 2037?
– Risks of cracks in bedrock, water seepage
Yucca
Mountain
Transportation
risks
• Uranium oxide spills
• Fuel rod spills (WI 1981)
• Radioactive waste risks
“Mobile
Chernobyl”
to Yucca Mtn.
Kyshtym waste
disaster, 1957
Orphans
– Explosion at Soviet weapons factory forces evacuation
of over 10,000 people in Ural Mts.
– Area size of Rhode Island still uninhabited; thousands
of cancers reported
Radioactive Waste Recycling
• Disposal of radioactive waste from nuclear power
plants and weapons facilities by recycling it into
household products.
• In 1996, 15,000 tons of metal were received by the
Association of Radioactive Metal Recyclers .
Much was recycled into products without
consumer knowledge.
• Depleted Uranium munitions for military.
Summary
• Nuclear energy has no typical pollutants or
greenhouse gases
• Nuclear waste contains high levels of radioactive
waste, which are active for hundreds of thousands
of years.
• The controversy around nuclear energy stems
from all parts of the nuclear chain.
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