http://www.sciencedaily.com/releases/2007/03/070321092710.htmOver the past 20 years, safety concerns dampened all aspects of development of nuclear energy: No new reactors were ordered and there was investment neither in new uranium mines nor in building facilities to produce fuel for existing reactors. Instead, the industry lived off commercial and government inventories, which are now nearly gone. worldwide, uranium production meets only about 65 percent of current reactor requirements.
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Currently, much of the uranium used by the United States is coming from mines in such countries as Australia, Canada, Namibia, and, most recently, Kazakhstan. Small amounts are mined in the western United States, but the United States is largely reliant on overseas supplies. The United States also relies for half its fuel on Russia under a "swords to ploughshares" deal that Neff originated in 1991. This deal is converting about 20,000 Russian nuclear weapons to fuel for U.S. nuclear power plants, but it ends in 2013, leaving a substantial supply gap for the United States.
Further, China, India, and even Russia have plans for massive deployments of nuclear power and are trying to lock up supplies from countries on which the United States has traditionally relied. As a result, the United States could be the "last one to buy, and it could pay the highest prices, if it can get uranium at all," Neff said. "The take-home message is that if we're going to increase use of nuclear power, we need massive new investments in capacity to mine uranium and facilities to process it."
Mined uranium comes in several forms, or isotopes. For starting a nuclear chain reaction in a reactor, the only important isotope is uranium-235, which accounts for JUST 7 out of 1000 atoms in the mined product. To fuel a nuclear reactor, the concentration of uranium-235 has to be increased to 40 to 50 out of 1000 atoms. This is done by separating isotopes in an enrichment plant to achieve the higher concentration.