The Price and Promise of Nuclear Science Nuclear radiation has it’s good points and it’s bad points.

Learning Objectives Describe the beneficial uses of nuclear radiation. Describe the advantages and disadvantages of nuclear power. Describe the hazards and current methods of disposal for nuclear waste. Give the significance of the incidents at “3-mile island” and “Chernobyl” to the nuclear power industry.

Uses of Nuclear Radiation 103 nuclear reactors in the world providing about 20% of the total electricity used each year. 70% of the capital ships in the U. S. Navy are powered by nuclear reactors. Medicine - –Radioactive tracers are used in diagnostic testing –Radiation therapy is used to treat cancer –Radiation is used to sterilize instruments –Radio-assay tests are used to determine levels of hormones in blood and tissues Weapons - At least 12 countries now posses nuclear weapons, and about half of them don’t like us. MAD Doctrine (Mutually Assured Destruction) – If you fire on us, then we will fire on you.

Nuclear Power Advantages and Disadvantages Advantages: –No greenhouse gases or other air pollutants produced. –Abundant supplies of domestic fuel. –Efficient, large amounts of energy produced from small amounts of fuel. –Nuclear powered ships run 10 to 20 years without refueling. Disadvantages: –Nuclear accidents can release huge amounts of highly toxic radioactive materials Three Mile Island Chernobyl –Nuclear waste remains highly radioactive for thousands of years and must be safely stored or disposed of. –Nuclear reactors are very expensive to build. –Potential for nuclear accidents or terrorist acts.

Nuclear Bombs and Explosions Hiroshima and Nagasaki –The only locations ever bombed with nuclear weapons –Both bombs had a 10 to 15 kiloton yield (compared to 10Mton) –One mile wide area around blast zone was leveled –140,000 casualties In the event of the explosion of an average nuclear bomb (10mT): –Within a 1-3 mile radius, 100% of all life and all buildings would be incinerated by 100,000° + temperatures (100,000,000° at blast site). –Up to 5 miles out 80% of the buildings and all life above ground would be destroyed by 200 mile per hour winds, 1,000° temperatures and extreme radiation. –Up to 10 miles away, all living things would be subject to lethal doses of radiation resulting in 90% mortality. –Dangerous radiation levels could be spread up to 200 miles away. –Area within 20 miles would remain dangerously radioactive for up to 20 years

Bombing Aftermath

Nuclear Accidents 2 nuclear accidents have occurred at power plants worldwide 3 Mile Island (1979) - Reactor damage resulted from a stuck cooling water valve. Small amounts of radioactive substances were released to the atmosphere. Reactor damaged beyond repair and never reopened. Chernobyl (1984) - Russian power plant that exploded releasing large amounts of radioactive material that spread over most of Europe. –50+ deaths during the initial accident –Radioactive fallout spread over 10 countries –It is estimated that 100,000 to 250,000 people will ultimately die from radiation exposure. –Areas around the power plant are still uninhabitable

Three Mile Island

Images From Chernobyl

Nuclear Waste The products of nuclear fission are extremely toxic radioactive materials that last thousands of years. Exposure to radioactive wastes can lead to: –Leukemia and various other cancers –Radiation Poisoning –Genetic mutations and birth defects Methods of Disposal –There is no absolutely safe way of neutralizing or disposing of nuclear wastes. –Rocket into the sun –Buried deep into the sediment in the deepest parts of the ocean –Buried underground –Stored indefinitely in non-porous rock formations Nuclear wastes are currently shipped to specialized storage facilities and stored indefinitely.

Key Concepts Review Nuclear power is widely used in medicine, electricity generation, scientific research and weapons production. Nuclear power promises to produce abundant electricity without generating large amounts of pollution. The disadvantages of using nuclear power are the inherent dangers in nuclear accidents and the storage and disposal of nuclear waste Nuclear waste remains hazardous and must be stored for thousands of years.