Nuclear Energy

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Traditional Aboriginal Knowledge

Nuclear Energy

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Ionizing Radiation
Examples of Radiation Risk
Nuclear Energy Fission
Fusion of Hydrogen to make Helium
Environmental Effects of Various Energy Sources - Comparison
Chernobyl, Ukraine
Radioactive Waste Repositories

adapted to HTML from lecture notes of Prof. Stephen A. Nelson Tulane University

Ionizing Radiation

Ionizing Radiation is radiation that ionizes (or removes electrons from) material that it passes through.
Examples of Ionizing Radiation include:

Radioactivity is natural; we have been bombarded by ionizing radiation from Uranium (U), Potassium (K), and Thorium(Th) as well as by cosmic rays all our lives.
Billions of years ago when life first started there was much more natural radiation than at present. Life has evolved with natural ionizing radiation. Some maintain that without the natural radiation which causes genetic mutations, evolution would not be possible.

Average Relative Radiation Exposure of Humans
Source Relative Exposure (%)
Cosmic rays 24
Terrestrial (U,K,Th) 32
Medical (X-rays) 40
Nuclear fallout 2
Misc. nuclear plants, waste 2

Ionizing Radiation
Dose (mSv) Effect
5,000 Lethal
1,000 to 2,000 Vomiting, fatigue, increased rate of abortion
within first 2 months, temporary sterility in males
500 Physiological damage
50 Maximum allowed for nuclear employees per year
1.0-2.5 Natural background

Dosage Effect
Extremely high dose burns and damage to brains, die within 48 hours
Lower Doses Diarrhea, bleeding and hair loss
Increased susceptibility to infection
Lowest (Natural) Dose Genetic mutation (some argue that this is necessary for evolution)

Examples of Radiation Risk

Nuclear Energy Fission

In a reactor U-235 or Pu-239 undergoes fission.

This entire system is enclosed in a containment building for further protection in case of a accident.
Comparison of coal and nuclear power plants:

As can be seen, the two types of plants are basically the same...the only real difference is in the method of heat generation. In Australia there is one nuclear facility which produces medical isotopes. In the U.S., as of 1988 there were 110 operable nuclear power plants, 1 in construction and 10 for which construction permits had been granted. None of the new plants were completed and put into energy production.

Environmental impacts and concerns of Fission:

Fusion of Hydrogen to make Helium

In this reaction a tritium nucleus (hydrogen 3) is combined with a deuterium nucleus (hydrogen 2) (fused) to create a helium 4 nucleus. This reaction releases energy and neutrons.

Environmental Effects of Various Energy Sources - Comparison

Environmental Effects of Various Energy Sources
Coal Oil Natural Gas Uranium
Disturbed Land 
    • Mining
    • Ash Disposal
    • Acid Mine Drainage
Brine Pipeline Construction Disposal of Nuclear Waste
Pipeline Construction
Oil Spills Carbon Dioxide Some Radioactive Gasses (Contained)
Nitrogen Oxides & Acid Rain
Carbon Dioxide
Radioactive Gasses

Environmental Effects of Various Energy Sources Coal Oil Natural Gas Uranium Disturbed Land Brine Pipeline Construction  Disposal of Nuclear Waste Pipeline Construction Oil Spills Carbon Dioxide Some Radioactive Gasses (Contained) Nitrogen Oxides & Acid Rain Carbon Dioxide Radioactive Gasses

Accidental Deaths per Billion Watt Power Plant
Energy Source Extraction Processing and Transport Power Plant Total
underground 1.7 2.32 0.01 4.0
strip mining 0.3 2.32 0.01 2.0
Oil 0.2 0.13 0.01 0.4
Natural Gas 0.16 0.03 0.01 0.2
Uranium 0.2 .011 0.01 0.2

Chernobyl, Ukraine

April 26, 1986 - the worst nuclear accident in the history of nuclear power generation occurred here. Operators of the plant were testing the emergency core cooling system. Power in the system rose rapidly. A steam explosion occurred followed by a hydrogen explosion. The graphite moderator began to burn. The outside containment structure, although substantial, was not adequate enough to hold the accident. Some 30 workers who were trying to prevent further  probems received lethal dosages of radiation. The local people as well as the world were not informed of the accident until several days later. The wind was blowing toward the northwest. Sweden was alerted to the problem when it found unusually high radiation counts in its atmosphere. Eventually some 400,000 people were evacuated from the area.
I131 has a half-life of 8 days. Many people recieved substantial doses of I131 as word about the accident was not released for several days.
Thyroid cancer in children that were living in this area has increased dramatically. Iodine is concentrated in the thyroid gland in humans.
Other cancers have not yet shown an increase, but it can sometimes take up to 20 or 30 years for an increase in certain cancer rates to show up.
The psychological stresses related to this accident seem to be having the worst health effects on the people.

Radioactive Waste Repositories

(examples from U.S.A.)
There is a need for repositories for two types of waste:
Low Level Waste
High Level Waste
High Level Waste Repositories

The government considered three possible sites for such a repository:
Congress has decried that only Yucca Mountain should be considered for non-defense waste. Yucca mountain has some advantages choice for this repository because:

A problem with Yucca Mountain is that the site area is in an area of active faults (earthquakes). If an earthquake occurred on a fault crossing the repository it could pump water into the repository and hasten migration of the high level waste.
Agencies involved in high level waste site selection:


The U.S. Energy Information Administration maintians a page covering many various energy sources, including coal and other fossil fuels, as well as nuclear energy.

 Nuclear Energy Pro's and Con's Page This page doesn't include any discussion in itself, but has a large array of links arguing both sides of the topics.