Yea basically the main contamination issue is that radioactive substances were spread around. Contamination of the surrounding area isn’t the only issue we have to deal with, nor is it the most serious, but it is generally is the most costly remediate.
The contamination problem is caused by radioactive matter spewed into the air and settling on the trees, buildings, ground etc… in the surrounding area.
The main remediation strategy is to remove everything in the surrounding area including the top ~3 ft or so of soil of the and haul it off to an underground landfill to slowly decay for at least a few hundred years safely separated from humans.
The economics of Bitcoin mining at scale force it to find an equilibrium where the cost of mining a Bitcoin is just a bit less than the current market value of a Bitcoin.
Electricity is the only significant variable cost at scale so the amount of electricity needed to mine a bitcoin ends up being a little less than however much a bitcoin can buy.
Thus one can estimate the total amount of electricity very accurately by simply taking the block rate (6/hr) times the block reward (~6.25 BTC) times the current price of a bitcoin divided by the wholesale price of electricity. You’ll get the upper bound for the amount of electricity being consumed.
Which by the way works out to around a TWh costing tens of millions of USD every single day. Which is more electricity than a small country
The only thing that will stop the waste is if the price of bitcoin drops. You can legislate it away, that won’t stop it, it will just move when it’s happening.