Quote: Originally posted by Mexitron |
Well, there was a suitable site called Yucca Mountain but folks got scared I guess. Might indeed find a use for the spent fuel someday.
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This is the reason why some of those who have looked at Yucca Mountain as a nuclear repository got scared:
Geology
The formation that makes up Yucca Mountain was created by several large eruptions from a caldera volcano and is composed of
alternating layers of ignimbrite (welded tuff), non-welded tuff, and semi-welded tuff. The tuff surround the burial sites is expected to protect human
health as it provides a natural barrier to the radiation. It lies along the transition between the Mohave and the Great Basin Deserts.
The volcanic tuff at Yucca Mountain is appreciably fractured and movement of water through an aquifer below the waste repository is primarily through
fractures. While the fractures are usually confined to individual layers of tuff, the faults extend from the planned storage area all the way to the
water table 600 to 1,500 ft (180 to 460 m) below the surface. Future water transport from the surface to waste containers is likely to be dominated by
fractures. There is evidence that surface water has been transported down through the 700 ft (210 m) of overburden to the exploratory tunnel at Yucca
Mountain in less than 50 years.
Some site opponents assert that, after the predicted containment failure of the waste containers, these cracks may provide a route for movement of
radioactive waste that dissolves in the water flowing downward from the desert surface. Officials state that the waste containers will be stored in
such a way as to minimize or even nearly eliminate this possibility.
The area around Yucca Mountain received much more rain in the geologic past and the water table was consequently much higher than it is today, though
well below the level of the repository.
Earthquakes
Nevada ranks fourth in the nation for current seismic activity. Earthquake databases (the Council of the National Seismic System Composite Catalogue
and the Southern Great Basin Seismic Network) provide current and historical earthquake information. Analysis of the available data in 1996
indicates that, since 1976, there have been 621 seismic events of magnitude greater than 2.5 within a 50-mile (80 km) radius of Yucca
Mountain.
DOE has stated that seismic and tectonic effects on the natural systems at Yucca Mountain will not significantly affect repository performance. Yucca
Mountain lies in a region of ongoing tectonic deformation, but the deformation rates are too slow to significantly affect the mountain during the
10,000-year regulatory compliance period. Rises in the water table caused by seismic activity would be, at most, a few tens of meters and would not
reach the repository. The fractured and faulted volcanic tuff that Yucca Mountain comprises reflects the occurrence of many earthquake-faulting and
strong ground motion events during the last several million years, and the hydrological characteristics of the rock would not be changed significantly
by seismic events that may occur in the next 10,000 years. The engineered barrier system components will reportedly provide substantial protection of
the waste from seepage water, even under severe seismic loading.
In September 2007, it was discovered that the Bow Ridge fault line ran underneath the facility, hundreds of feet east of where it was
originally thought to be located, beneath a storage pad where spent radioactive fuel canisters would be cooled before being sealed in a maze of
tunnels. (don't you just love these "experts"? And they think they are qualified to make 10,000-year predictions!) The discovery required
several structures to be moved several hundred feet further to the east, and drew criticism from Robert R. Loux, then head of the Nevada Agency for
Nuclear Projects, who argues that Yucca administrators should have known about the fault line's location years prior, and called the movement of the
structures “just-in-time engineering.” In June 2008, a major nuclear equipment supplier, Holtec International, criticized the Department of Energy's
safety plan for handling containers of radioactive waste before they are buried at the proposed Yucca Mountain dump. The concern is that, in an
earthquake, the unanchored casks of nuclear waste material awaiting burial at Yucca Mountain could be sent into a "chaotic melee of bouncing and
rolling juggernauts".
Probably not a good idea to put spent nuclear fuel with a who-knows-how-long half-life cycle in a volcanic area where it could be launched into the
atmosphere some day--to say nothing of the earthquakes coupled with the fractures that lead directly down to the water table...no matter what the
"experts" say about how safe containers might be built. We have some containers up here at the Hanford Nuclear Reserve that are slowly leaking their
radioactive waste into the Columbia River. The reason nobody can settle on a place to build a storage facility is that there just isn't a place that
is guaranteed not to be subjected to a natural disaster some day. Hence, they keep piling the spent fuel in "temporary storage."
[Edited on 7-25-2015 by Bajatripper] |