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Fallout from Chernobyl.ppt
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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