Without low enough costs (including subsidies), miners will move elsewhere. But the effects of using largely excess power (hydroelectric) on the environment are nothing like strip mining operations.
Obviously I don't mean strip mining in the literal sense. I do mean opening the door to operators who'll come in and milk things as intensely as possible and then bugger off having contributed nothing to the jurisdiction that lured them there other than exploiting the subsidies paid for by the little people.
I don't think some local governments are realising how hungry, fleeting and predatory mining operations are. It's not like building an ongoing business that's going to settle in and thrive. They're more like locusts who'll move on once everything's been consumed.
If they're OK with that from the off then cool. I'm not sure they are.
There's a lot of excess generated electricity that would otherwise be wasted because it's difficult to efficiently store. Hydroelectric power during wet seasons is a good example. Mining operations can definitely have a symbiotic relationship with power plants if only as a matter of load balancing.
The ideal is to create the proper incentives (and perhaps disincentives) to drive miners towards excess capacity, where they can work with power plants to soak up excess power without spiking demand. Right now, miners just go where it's currently cheap -- probably with little regard for grid capacity -- and then they drive up everyone else's generation costs and/or threaten the entire power grid. That's a problem.
