1. Upgrade the Waste Rock

This improves the NPV 8% from $513M to $927M using my rough calculations here.

2. Improve the Recoveries

I have no idea what type of improvements are possible. Assuming a 1% improvement in each metal, the NPV 8% goes from $513M to $636M.

3. Get Value for the Rhenium

With the assumptions in the feasibility study, the rhenium could potentially produce an extra $24.6M in revenue as I showed here. However, the additional cost of shipping to a capable roasting facility as well as the additional roasting costs likely mean the rhenium won't add much value, if any at all. Assuming we get $5M in extra profit from the rhenium, the NPV 8% improves from $513M to $549M.

4. Expand to 180,000 tpd

This is a tough one to put a number to. An expansion to 180,000 tpd increases capex, decreases mine life, and increases annual cash flow. This likely will result in an improved NPV on paper, but from a practical standpoint it doesn't seem to make sense at this point.

5. Reduce the capital and operating costs

I don't think there is much room for improvement here. The Merit review likely brought costs down as low as possible.

6. Shorten the Development Timeline

Again, I don't think there is much room for improvement here. Even if we did reduce the development timeframe by a year it would have a minimal impact on the economics. With Copper Fox currently in charge of the schedule we need all the time we can get.

Combining 1, 2, and 3 results in an improvement of the NPV 8% from $513M to $1044M. These numbers are all very rough estimates but it gives a good idea of the impact of various improvement opportunities.