Functional mill, yes.
The ability to get gold out of the ground, questionable.
I am by no means an expert...but it stands to reason that if Barrick down the road is using a different process to extract gold from the same land, then maybe PCFG should use the exact same process.
Otherwise, it's just a tin building in the middle of the dessert that tries to get gold out of the ground using a method that doesn't look like it's working.