The Problem of Nuclear Waste Disposal

US Policy:

Until the mid-1970's, U.S. utilities planned that used fuel from nuclear plants would be kept on-site for a few months, and then be shipped to a reprocessing plant to recover plutonium and uranium. Consequently, plant specifications had limited spent-fuel storage capacity. Up until 1982, the federal government intended to receive spent fuel for disposal at a specified date. The date has continuously been postponed. The Nuclear Waste Policy Act of 1982 determined that the Department of Energy would accept the used fuel to be transported and disposed in geological foundations by 1988. However, this schedule has been delayed also, and no facilities have been constructed.

Internet Resources on Nuclear Waste:

• The Yucca Mountain Project
• Federal Republic of Germany
• Nuclear Waste Disposal Fund
• Comprehensive Resource
• 1995 Nuclear Waste Disposal Funding Act

The basic method of Nuclear Waste Disposal is to bury it in the ground and hope it doesn't leak out. More specifically, to identify stable Geological Foundations which can host the material for 10,000 years, like Yucca Mountain Nevada:

Here is what some countries are doing/considering but note that most nuclear waste is still stored on site.

• US: Yucca Mountain Nevada - volcanic tuff (dense volcanic ash)
  What Nevada Thinks
• Canada: Studying disposal in crystalline rock
• Spain: Salt, Granite and Clay
• France: Granite, Clay, Schist or Salt
• Switzerland: Studying disposal in crystalline rock
• Belgium: Studying disposal in clay
• UK: Plans to "reprocess" after interim storage
• Sweden: Crystalline Rock
• Japan: Studying disposal in granites and tuff
• Finland: Studying disposal in granite
• The Netherlands: Interim storage and studying disposal in salt
• Germany: Has salt disposal facility at Gorleben

Methods of Burial of Waste --> relatively inexpensive --> about 1% the cost of generating energy from nukes to begin with.

Other options for high-level waste disposal:

• launch it into space
• transmute it in accelerators or other reactors
• place containers on Antarctic Ice sheet --> they melt through the ice until they reach the ice-rock interface
• Deep salt beds --> free of water, self sealing and will flow from waste decay heat to plastically seal the wastes

Types of High Level Nuclear Wastes:

Fission Products:

⁹⁰Sr and ¹³⁷Cs --> half live of 30 years: These are harmful due to gamma ray emission

Neutron Absorption Products:

²³⁹Pu --> half live of 24,000 years (reprocessing can eliminate ²³⁹Pu but this is prime weapons grade fuel). ²³⁹Pu is harmful because its highly chemically toxic.

Other Issues:

One 1000 mega Watt nuclear facility generates 2 cubic meters of waste per year

80 million gallons of waste are stored in underground tanks at Hanford, Washington and Savannah River, South Carolina.

Whatever disposal mechanism is chosen, transport of nuclear waste remains a concern. Waste is transported in armored casks which are known to have withstood and 80mph locomotive crash test. But states will pass legislation forbidding the transport of nuclear waste within their borders. So, it probably won't even be possible to move it, should we even find a "safe" location.

Finally, decommissioning of nuclear power plants is a problem. Trojan closed in 1993 but only $40 million were allocated for cleanup when the true costs is 10 times that much. Entombment - encasing the whole plant in concrete, is not cheap.

And finally, a brief comment on Fusion Prospects:

How the Sun Works

Normal fusion requires very high energy in order for the protons to overcomb their natural electrostatic repulsion, Temperatures of at least 5 million degrees are necessary.

The main problem is finding a containment mechanism to contain this hot plasma. Work to date involves sophisticated magnetic bubbles and trapsa tokamaks.

inside view

Outside view

To date, these tokamaks require more energy to sustain their integrity than the fusion experiment releases. Sometime, probably more than 100 years from now, we may figure this out.

Frequently Asked Questions about Conventional Fusion

Cold Fusion: Believe it or Not

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