Moon Seen As Nuclear Waste Repository
Aug 22 (Science - space.com) - As the debate rages over using the
Yucca Mountain as a burial ground for thousands of tons of
radioactive material, a better site for unwanted nuclear waste holds
its mute vigil in the skies above the Nevada desert: the Moon.
After 20 years of study, last July President Bush ( news - web sites)
signed a bill making Yucca Mountain the planned site to house 77,000
tons of nuclear refuse. The site is to be open for business by 2010,
located in Nevada desert, 90 miles (150 kilometers) from that
gambling Mecca, Las Vegas.
Since its approval, politicians, scientists, lawyers, environmental
activists, and protesting citizens have been locked in heated dispute
over the $58 billion project.
Advocates of the plan say the repository site is safe. Radioactive
materials can be responsibly and securely tucked away in the mountain
for some 10,000 years.
However, others fear, among a list of worries, that transporting
nuclear waste over city streets and state highways is asking for
trouble, as well as being a tempting target for terrorists.
"No site for a long term, nuclear waste repository within Earth's
biome or accessible to low-tech terrorist threat is acceptable,"
argues Sherwin Gormly, an environmental engineer for Tetra Tech EM
Incorporated in Reno, Nevada.
Gormly contends that the waste issue is the single most important
problem limiting nuclear power development. A revolutionary change,
he said, is required to break the impasse.
"We need to seriously reconsider more advanced concepts, including
repository options on the Moon," Gormly said.
In the past, thoughts about a lunar nuclear waste repository have
come and gone.
A new twist in the Gormly plan is using off-the-shelf
intercontinental ballistic missiles (ICBMs), warhead targeting
technology, and a reusable suborbital launch vehicle. It's an idea
whose time may have returned, he said, broaching the notion last
month at a Return to the Moon workshop held in Houston, Texas, held
by the Space Frontier Foundation.
The concept employs a low-cost, highly reliable suborbital space
plane. Flying to high altitude, the piloted plane then dispatches an
ICBM upper stage assembly. Multiple Independent Reentry Vehicle
(MIRV) hardware, guidance equipment, and modified reentry vehicles
carrying a casks of plutonium or waste material top this stage, which
ignites and speeds into space.
An internal targeting system within the reentry vehicles precisely
places the casks of waste headlong onto an outbound lunar trajectory.
The target would be a small lunar crater with steep sides. In later
years, the flight path of the casks could be aided by final guidance
equipment installed on the crater rim. That will assure an even more
accurate bulls-eye impact of the incoming waste-carrying
containers.
One by one, the casks smack into the Moon. The soft deep lunar
regolith in the impact area should ensure proper waste burial.
Plowing into the lunar surface at high speed, the waste would be
buried under several feet of glassified regolith, Gormly said.
The impact area would be highly contaminated, the environmental
engineer said, so a clearly delineated repository area would be
needed. "However, the problem of waste migration would be eliminated
because the lunar surface has no hydrosphere."
The situation in Nevada is a classic case of the "Not In My Back Yard
(NIMBY) syndrome," Gormly said. Furthermore, the reality of
the situation is that waste streams from medical sources and weapons
grade plutonium production are also of concern.
"A solution outside of the biome and out of casual reach must be
found," Gormly said.
"The lunar surface is a sterile, hard radiation environment with
great geological stability and no potential to pollute the Earth
biome...a potential that is inevitable to all Earth sites due to
groundwater," Gormly said. "NIMBY politics don't apply to the lunar
surface at this time and can be avoided in the future by good
planning and negotiation of beneficial use agreements," he added.
Once deposited on the Moon, nuclear materials would be of potential
value. Access to the lunar repository site by future Moon
dwellers could be regulated. Retrieval, reuse, even reprocessing of
the nuclear material can enhance both lunar operations and
further deep space commerce, Gormly speculated.
"The reality of the situation is that this material is a political
liability today and a resource tomorrow," Gormly told SPACE.com.
The development of a lunar waste repository is an off-world
opportunity to develop positive political and social momentum. This
proposal is simple, safe, and uses current off-the-shelf technology,
Gormly concluded.
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