Nuclear waste disposal

[midnight armadillo]

Question: why can't nuclear waste be disposed in such hard-to-reach places as the bottom of spent oil wells? Some of those are extremely deep.

Edit: It looks like Finland plans on sticking iron casks 400-700 meters into bedrock: http://www.stuk.fi/english/nuclear_materials/final_disposal.html

[NNadir]

1. It is dumb to bury spent fuel.

It is extremely valuable material.

If it is isolated underground for some period, it should be done in such a way that makes it very easy to recover.

It will be a sensible world when people stop obsessing about so called "nuclear waste" which has proved rather harmless to store while they are completely indifferent to the far more widely distributed and deadly wastes of the fossil fuel economy - which are killing people every day.

It is, in a word, irrational.

[ManiacJoe]

5. Valuable in what way?

I have never heard this before.

[Massacure]

6. Nuclear "waste" in all reality contains rare metals and fissile materials.

The only reason it isn't bred and recycled is because it is just cheaper to dig it out of the ground.

One of the reasons the nuclear industry should be controlled by the government, IMO.

[dcfirefighter]

7. Externalities

it's my impression that *most* of nuclear power's externalities are accounted for in it's price. My guess is that the only real 'leakage' is at the mine. Strict regulations there would favor reproccessing.

I don't like the idea of a government - run nuke plant. From what I've seen in DC, private contractors actually tend to do a better job of O&M than either DC or Federal government.

I do like the idea of 24/7/365 on-site government (and Int'l NGO) oversight. I also tend to favor Adm. Rickover's suggestiont that it be done by USN Nuclear Officers.

One shortcoming in nuclear power, as I see it, is the seeming inability for small-scale installations that can be scaled to demand and located near enough residential & commercial areas to provide district heating. This may not be a technical shortcoming, but it is a practical one nonetheless. You can pipe high temperature water quite a way with little losses, provided the piping is large enough and insulated enough.

[NNadir]

8. Here is a calculation of the value of various components of so called

"nuclear waste."

The United States has about 75,000 metric tons of so called "nuclear waste."

When a fuel rod in a nuclear reactor is removed because it can no longer be made to critical, about 95% of the uranium remains unchanged. The U-235 is not entirely depleted, but in fact remains slightly enriched with respect to natural uranium, having an enrichment of around 0.9 % to 1% U-235. As such this uranium could be immediately be used to fuel a CANDU type reactor. It could also be subject to re-enrichment to obtain more highly enriched fuels. About 95% of a spent fuel rod is uranium, meaning that 71,250,000 kg remaining, worth about $50/kg. The value of this material is thus about 3.6 billion dollars.

One prominent fission product formed by the fission of uranium is Ruthenium. When uranium-235 is fissioned about 17% of the fission events yield a stable isotope of ruthenium. The price of ruthenium is roughly 85 USD per troy oz. or $2576/kg. The total quantity of fission products represents about 675,000 kg for a total value of $1,668,000,000. In order to sell this ruthenium, one would be advised to wait 15 years in order for any Ru-106 (half life 373.59 days) to decay to background before using the remaining ruthenium in open systems.

Another prominent fission product is rhodium. Rhodium results from about 3% of the fissions and is represented by 114,000 kg of this important catalytic metal, easily outstripping the world supply from mining, which represents about 3000 kg/per year. The price of Rhodium is $2,740/troy oz or $83,000/kg. Thus the total value of Rhodium that could be obtained from so called nuclear waste is about 9.5 billion dollars.

Another prominent fission product is palladium metal. Palladium obtained from nuclear reactors containing the long lived isotope Pd-107 which has a half life of 6,500,000 years. The long half-life and low fission yield with respect to other isotopes lead to a mild specific activity for this metal of 4 millicuries per gram. This will require the use of this palladium in closed systems, such as large continuous chemical reactors for certain hydrogenation reactions or in the catalytic cracking of future synfuels. The current price of palladium is $198/troy oz. or $6000/kg. Thus the total value of the palladium in spent nuclear fuel in the United States is around $361,000,000.00. Some uncontaminated palladium-106 can be found from the decay if ruthenium 106 as described above.

So called "nuclear waste" typically contains 1% plutonium, which sells for about $1000/kg. Thus there are $7,500,000,000 worth of plutonium in nuclear reactors. There are certain configurations in which plutonium can be used to greatly extend the burn-ups of nuclear fuels, yielding fuels that provide as much as 150,000 MW-days/ton of heavy metal. This compares with typical fuel performance in the 30,000-40,000/MW-d/THM in modern day reactors.

Thus the total value of the nuclear materials found in the accumulated spent fuel in the United States is roughly 22.5 billion dollars. There are some other substance is this so called waste that could easily be made to have economic value.

Sources: http://www.platinum.matthey.com/producer_index.html

http://atom.kaeri.re.kr/

The calculations are mine, and are simplified with respect to certain minor effects in the normal fuel depletion equations, which must be solved analytically.

[Massacure]

2. Why do people protest building research breeder reactors?

It is in our interest to breed fuel down so it is less radioactive the original mined ore after 300 years.

I know some people get mad for answering a question with another question. So i'll give you a straight forward answer. Humans in general are stupid.

[midnight armadillo]

3. I agree with both of you

However, the problem of nuclear waste looms large in the public's perception of nuclear power, and Yucca Mountain isn't going to be a viable disposal solution.

If breeder reactors aren't politically feasible, then you gotta dump it somewhere...

[Oerdin]

4. The sad thing is...

This is a political and not a technological or economic problem. Global warming caused by our use of green house gas producing fossil fuels is a bigger threat then the tiny amounts of nuclear waste produced by nuclear energy and nearly all of that "waste" ca be recycled. We have crap loads of existing nuclear fuel just from the dismantling of our nuclear weapons due to the SALT treaties which we don't know what to do with and which we are storing anyway.

Any body who takes a hard and realistic look at how to reduce our green house gas production without massive disruption to our economy will see that nuclear power is the anwser. It will let us continue the life style we all want while slashing the production of green house gases which are harming our enviroment.

[FreeMason]

9. Problems.

The problems of iron casks is that iron is highly corrosive even in bedrock which the hole dug will eventually erode if even that is necessary, and allow the casks to corrode.