President Bush signed into law yesterday the measure approving Nevada’s Yucca Mountain as the nation’s nuclear-waste burial ground, which was approved two weeks ago by Congress. The signing, closed to journalists and attended by only a handful of allies who were instrumental in brokering the bill’s passage, marks the official end of Nevada’s legislative fight to keep the highly radioactive waste out of the state. But in a statement issued after the signing, Nevada Gov. Kenny Guinn (R) said the battle would merely change venues, moving from Capitol Hill to the courts: “I have always believed that our best chance in defeating Yucca Mountain is in the federal courts, where impartial judges will hear the factual and scientific arguments as to why Yucca Mountain is not a safe place to store this nation’s high-level nuclear waste.”