Plutonium lifespan in U.S. weapons much longer than thought: report

The plutonium used to trigger U. S. nuclear warheads and bombs will remain reliable for about 100 years, far longer than had been believed, the U.S. National Nuclear Security Administration (NNSA) said.

Studies have shown that the degradation of plutonium in U.S. nuclear weapons would not affect warhead reliability for decades, The Washington Post reported Thursday, citing NNSA Administrator Linton F. Brooks.

An independent panel of renowned scientists and academics known as the Jason group reviewed the studies by the Los Alamos and Lawrence Livermore national laboratories and concluded that "most plutonium pit types have credible lifetimes of at least 100 years, " the newspaper quoted a NNSA statement as saying.

Results of the studies could affect the Bush administration's plans for building a new generation of nuclear weapons under the Reliable Replacement Warhead (RRW) program. A major reason for going to a new nuclear warhead was the belief that highly radioactive plutonium would degrade so much within 45 years that it could affect the reliability of currently deployed and stockpiled nuclear weapons, which were built beginning in the 1960s, according to the report.

The present refurbishment program, which does not include the nuclear package, is directed at upgrading for 20 more years the aging conventional explosives and hundreds of the thousands of non- nuclear components in each weapon, the report said.

Robert W. Nelson, a senior scientist associated with the Union of Concerned Scientists, told the newspaper on Wednesday that the studies "dramatically undercut the prime justification for having to rebuild the existing stockpile." The core plutonium component " will not need to be replaced for 50 years or more."

NNSA officials said however that they did not agree that the plutonium findings mean that the RRW program does not need to go forward. "Plutonium aging is but one variable that can affect overall system reliability," the NNSA statement said.

Source: Xinhua



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