About 15 miles that used to have small nuclear reactors, all of them for power-generation research. One in fact did run a generating-station once connected to the National Grid.
All gone. Britain and France were world-leaders in this field, but first France pulled out of the co-operation (I don't know the reasons), then blinkered UK governments of both parties over the years threw it all away in their usual manner.
Most of the site is now an industrial-estate, and the two largest reactors, in an area cordoned off from the rest, are being dismantled. The other reactors, about 10 of them I think, were much smaller and have long gone.
Did their presence worry me? No.
As for dangerous chemicals, to my knowledge there are none in large quantities around here, but the regulations on them are now so tight I would not worry unduly. Admittedly the regulations were based on lessons learnt the hard way though.
I just read today that they as "dismantling" San Onofre...the one nearest to us. What do they do with the radioactive stuff? How deep do you have to bury it? How long is harmful? I shall ask. Thank you for your reply Durdle! :)
There are three forms of ionising ("radioactive") radiation, and the hazard depends on the type and amount.
A radioactive material also has a "half-life" by which half of it changes to a more inert form in that "life", half of what's left in the next "life", and so on. Some half-lives are short, others, including that of uranium, are in many millions of years....
but....
the radiation type is important because that determines the shielding necessary. Uranium emits alpha particles that are dangerous but easily stopped by quite thin materials.
A lot of the parts and materials from dismantled reactors and fuel-processing equipment can be washed off, concentrating any radioactive material from them into smaller volumes.
It is not depth of burial that matters, but stability and long-term site security, and that can mean deep burial but as an effect of those criteria. The first requirement is encasing the radioactive material in something that keeps the radiation in, and will not degrade significantly. The next is where to put it, where it will remain safe and undisturbed for as long as necessary - and bearing in mind we cannot safely predict our world 50 years ahead, let alone, say, 5000.
So they use fairly deep rock burial in geologically-stable regions - old metal mines could be suitable. "All" that's necessary then is being as sure as reasonable that the packaging will survive, probably under water that might be fairly aggressive due to natural minerals in it - but would keep the containers cool.
There was an interesting proposal made by years ago, I suppose by the United Kingdom Atomic Energy Authority (the scientific civil-service organisation overseeing nuclear research), to package the "strongest" stuff in sealed containers placed in vessels shaped a bit like torpedoes. These would be released in deep ocean areas known to be accumulating silt at geologically rapid rates, so the sea floor is covered by a deep, soft mud under little or no currents. The "torpedoes" would dive nose-first and bury themselves deeply in the ooze, which would tend to fall back over them. And there they would stay, kept cool by the wet mud, away from the wildlife, safe from being found or dredged up, for tens of millions of years while the material in them slowly loses its radioactivity.
What happened? The Seamen's Union blocked the experiments by refusing to crew the trials ships.
What reason did they give for refusing to do that? Did they think it would endanger them in any way? Sounds like a great plan to me.
Of course if we have massive earthquakes it could disrupt or dislodge them. If we have space debris crash into our earth and hit any of them maybe it could crush them thereby exposing all that material to the oceans and by evaporation in the air? Or is that a stretch?
For sure they didn't know 100 years what we would be today and what will be (providing we still exist) in 100 years is anyone's guess. Thank you for your very informative reply Durdle. Do you worry about it at all or is that so far down the list of things to worry about you don't even think about it? :) What do you worry about the most?
Durdle 