Re: Also
Private firm drills a well or digs a coal mine, loses money and goes bust, the liability for the safety of those disused workings falls on the public purse
Well that's the fault of the law, which ought to require a company engaging in new drilling or mining to post a bond/insurance sufficient to cover the cost of remediation.
Yeah yeah I know the fossil fuel proponents will claim this is an unreasonable regulation and you aren't doing the same to green energy. Fine, require the same for people putting up wind or solar farms that there is a bond set aside to fund their decommission. Of course, doing that might be the death of nuclear, due to the essentially unlimited liability in the event of a Fukushima scale disaster so if the government wants to encourage nuclear they might have to be the insurer of last resort there.
Can't do anything about the past mistakes, but you can learn from them and prevent future ones from happening.