“...we have many abandoned mines which are empty and pose no threat to any water table. throw the waste down there and fill it up with concrete and dirt.”
Sure that would work. But the problem exists that this radwaste has a half-life of hundreds of thousands of years. There has never been a civilization that lasted that long and the whereabouts of dangerous waste is likely to be forgotten.
It makes more sense to place the radwaste somewhere man is not going to have access in the next half-million years. Do you savvy?
And the only reason for that is that the spent fuel has an incredible amount of energy left in it.
The way we operate our nuclear reactors is like throwing a big fat log on a campfire, warming our hands over it until the bark gets a little charred, and then taking it off and throwing it away.
We use only about 2% of the energy available in nuclear fuel, and yet people are talking about throwing it into the sun?? What a waste!!
If you strip out the actual waste products from the spent fuel - instead of treating spent fuel as if it were all waste - the remaining actual waste only has a half-life of a few decades to a few hundred years.
If you use the right technology, nuclear reactors will CREATE MORE FUEL THAN THEY BURN, in some special cases nearly twice as much. In fact in a normal nuclear reactor, over a third of the energy produced comes from fuel that was newly-created inside the core.
In the uranium atom, we have been given the means to supply every last one of billions of humans on this planet, and any other planets, all the energy they need until the sun burns out, if only we are wise enough to use it.