Transcript
NARRATOR
But what makes Yucca Mountain such a suitable candidate for this sort of facility?
EXPERT
t has various attributes. It's isolated. It's in a desert region with very low rainfall. There's a very deep water table, so the repository is above the water table, relatively dry, and even would be above the water table if the climate changed dramatically in the future and that region became wetter.
They can go into the side of the mountain and still be well beneath the surface and well above the water table. Compacted volcanic ash produced by these large explosive eruptions is relatively easy to drill. It's also got some chemical attributes whereby there's a lot of a certain type of mineral called a zeolite, which is a very absorptive mineral often used in philtres. But if there were any leaks in the future, it's hoped that this rock would actually absorb many of the radionuclides that might be travelling through the rock.
It's also located on a US government military range next door to the place where all of the atomic bomb tests were done in the 1950s and '60s. So there've been above ground and below ground explosions conducted there over a long period of time until the ban to have such experiments came into effect. It's very isolated in terms of access. You have to have special permission to go within this very large area in the Nevada desert.
NARRATOR
So how will the US transport 11,000 canisters of nuclear waste across its state lines? But how will it be treated when it arrives?
EXPERT
The spent nuclear fuel from a power station would be - the rods would be pulled out of the reactor, stored locally in some ponds or pools adjacent to where they've been used. The waste would then be put into some sort of a temporary transport container, moved to the repository site where it would be put into the permanent containers, and then sent on its way into the mountain, into the repository where it would sit for a very long period of time. So the transport is planned to be by rail, mainly, from the various places where the waste is stored to the Yucca mountainside.
In the future, although the US doesn't reprocess the waste right now, it may start, as other countries do, reprocessing the waste into other forms. Some of the reprocessed material might be used for other purposes. Then eventually, the waste would be sent to a geologic repository. Then they would be put into a sort of truck and remotely loaded into the tunnels that they're going to be drilled in the side of the mountain to store the waste.
NARRATOR
Radionuclides take thousands of years to release their energy and become less harmful, so for how long might the mountain repository function?
EXPERT
A repository like Yucca Mountain is being evaluated on how it would perform over 10,000 years, and even out to a million years. It's quite unusual for anybody, even geologists, to think ahead 10,000 years. I mean, we're very good at looking back 10,000 years or 100,000 years or a million years into earth history. But I think very few engineering or planning exercises look forward that long, way beyond the sort of normal future that we look at.