"CUU evaluation.....This may be a really dum question. But how do they do this?"

That’s what the BFS is attempting to do; to put a value on SC.

Conceptually, based on the planned production capacity, one can calculate the revenues from the various minerals, less the operating costs, to arrive at a net revenue each year for the next 30 years or whatever they use as the production period. Discount this revenue stream back to the present for the NPV (net present value). Similarly, one estimates the capital investments required for the equipment and discount that expenditure to the present (a negative NPV). Add the two NPV and you have the NPV of SC; a theoretical current value of SC, based on the planned production capacity.

Of course, it involves many assumptions and projections including the production capacity, mineral grade and potential tonnage at each grade, selling price for each mineral, operating costs, discount rate etc. over the next 30 years.

This is a very simplistic and conceptual look at how a value can be calculated.

Not sure if that was your question.

JMO GLTA!