Low-yield nuclear tests can be conducted in underground caverns in ways that make detection almost impossible.

CENTERFORSECURITYPOLICY: Center for Security Policy | A New Skepticism on Arms Control, By James T. HackettThe Washington Times, 18 October 1999

Thermal vents among the trees on the hillsides let off jets of hot steam from underground caverns.

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One answer is to use the energy to compress air, which can be squirrelled away in hermetically sealed underground caverns.

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Each year, the Pentagon and the Energy Department must certify to the president that the nuclear weapons stockpile is safe and reliable and that there is no need to resume tests involving the detonation of nuclear warheads and bombs in underground caverns, as was done until 1992.

CENTERFORSECURITYPOLICY: Center For Security Policy

This involves compressing air and storing it in large repositories, such as underground salt caverns.

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The energy firm said it would continue to store waste on site until a deep geological disposal facility was made available - similar to the storages created in underground rock caverns in Finland.

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Kitsch roars its dinosaury head at Grand Canyon Caverns, luring you 21 stories underground for an ubercool cavern tour and even an overnight stay.

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M. has basked in the fame of nearby Carlsbad Caverns National Park, with its awesome underground stalactites and stalagmites.

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But as these visions are developed, their potential to become a reality will depend on the success of facilities such as the Jurong Caverns -- considered by Tan as a prototype for underground developments in Singapore.

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