Sure, but to truly avoid all naive readings would be to analyse the total impact of constructing the hydro plant in such an out of the way place for the purpose

Sure, but to truly avoid all naive readings would be to analyse the total impact of constructing the hydro plant in such an out of the way place for the purpose of mining. There's an emissions cost to producing the equipment required to construct the hydro plant. There's an emissions cost associated with constructing the hydro plant. This is multiplied if you are building it in an area without heavy industry (no existing demand, remember?) - because you have to construct your own support infrastructure and road network to build and service the plant. Not to mention the impact of the now flooded 'wilderness' (which is highly likely to contain carbon sinks). Or the impact to forestation and vegetation downstream.