
Every few weeks we see another feasibility study completed. Normally the numbers will look fantastic. The feasibility study shows that a project could work, but will it really work?
A positive feasibility study is the moment a mining project is supposed to come alive. It’s the point where geology, engineering, and economics merge into a real (i.e. bankable) business case. However, it is also the starting point of an entirely different and more difficult path.
The roadblocks between a feasibility study and a producing mine can be numerous, varied, and often have nothing to do with the geology itself. A government can change the tax regime, or a community can withdraw support. The commodity prices can turn, or environmental permits can be challenged in court. A company’s own board can lose conviction. Understanding this development gauntlet is the difference between allocating capital to projects with returns and those that will consume capital for a decade.
Stalled projects will experience several of the roadblocks simultaneously. A single roadblock might be surmountable, but multiple roadblocks may not be.
Many of these roadblocks will be identified during confidential third-party due diligence by potential partners, acquirers, or financiers. Hence investors may never learn the actual truth as to why the project is stalled and are left guessing why.
I have been part of due diligences on behalf of lenders and have seen the negative reasons never make it to the public eye. Sometimes the company may itself not know why a project was declined, although they can make an educated guess.
The following is a checklist of the various pitfalls leading to the study graveyard. Check off all those that you think apply to your favorite stalled project. Be honest. Typically, more than one will apply and they will tend to compound.
Geotechnical & Geological Risk
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Review of the block modelling reveals concerns with grade, continuity, or metallurgical recovery.
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Review of the expected geotechnical conditions reveals mining concerns associated with faulting, weak ground, karst, high water inflows.
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Metallurgical complexity understated in feasibility (refractory ore, penalty elements).
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Resource classification is suspect and a lot more infill drilling is required, at a high cost.
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Hydrology issues, e.g. acid rock drainage severe and difficult to manage long term and becomes a corporate liability.
Technical & Engineering
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Feasibility study found to be technically flawed upon review.
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Project is very complex and will be difficult to build on budget and on time, as well as difficult to staff with qualified operating personnel.
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Processing technology unproven at scale, ore sorting risk ,etc.
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Infrastructure assumptions (power, water, road) prove more costly or difficult.
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Mine plan optimistic on strip ratios, mining rates, or equipment productivity.
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Tailings storage facility design issues, high risk, or siting problems.
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Water rights access insufficient or contested.
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Offsite infrastructure (road, rail, or port) inadequate and too costly to build.
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Remoteness – labor costs and retention problems underestimated.
Permitting, Regulatory, and Social License
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Environmental impact assessments likely to be rejected or endlessly delayed.
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Perceived difficulties to get operating licenses, water licenses, or discharge permits.
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Regulatory framework uncertain and changes mid-process (new environmental laws, mining codes).
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Federal/state/provincial jurisdictions overlap creating jurisdictional gridlock.
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Permits granted but successfully challenged in court by third parties.
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Indigenous or First Nations consultation failures, failure to negotiate community benefit agreements acceptable to all parties.
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Local community opposition leading to blockades or political pressure.
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NGO campaigns attracting negative media attention that spooks investors or lenders.
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Religious, cultural, or heritage site conflicts with site plan.
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Mineral title disputes persist with overlapping claims or historical issues.
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Land access agreements with surface rights owners difficult to acquire.
Political & Country Risks
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Government instability, coup, or change of administration hostile to mining.
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Retroactive tax increases, windfall profit taxes, or royalty rate changes.
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Nationalization or forced renegotiation of mining agreements.
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Corruption demands that the company is unwilling to meet.
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Sanctions, war, or civil unrest making the region inaccessible.
Financing & Capital
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Inability to secure project financing (debt or equity) due to financier risk appetite, commodity price outlook, or lender requirements.
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Cost overruns discovered during reviews that make the economics unviable.
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Declining commodity prices between feasibility and financing.
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Owner balance sheet too weak to fund large construction; inability to attract a joint venture partner.
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Royalty or streaming deals entered into that are too dilutive, making equity unattractive.
Corporate & Strategic
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Management change leading to strategy pivot away from the project. The internal champion is gone.
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Company acquired by a buyer with a different portfolio strategy — project shelved.
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Board loses conviction or knows they cannot manage this; project deprioritized in favor of capital returns or other assets.
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Key technical personnel depart, taking institutional knowledge with them.
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High market cap of owner makes the acquisition cost high, when considering the capital cost to build must also be incurred by the acquiror. This will lower the return.
Market & Macro
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Commodity price collapse, or forecasting an oversupply, makes the project sub-economic even with a positive study.
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Input cost inflation (energy, steel, labor, reagents) erodes profit margins.
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ESG-driven investor exclusions make it impossible to raise equity capital.
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Offtake agreements cannot be secured on acceptable terms. This can be important in industrial and battery mineral projects. This may require focusing on downstream processing into upgraded specialty products, increasing risks and costs.
Conclusion
The list of potential production roadblocks is extensive. Moving from the study stage to production is very difficult and very few can do it successfully. A positive feasibility study is a necessary but far from sufficient condition for production.
When projects stall, it is likely due to multiple factors listed above. A ranking analysis may conclude the compounding effects of the perceived risks makes the project a no-go for financiers.
Some people will say be thankful that more projects don’t advance to production, because we would likely see more failures as the risks come to bear Ideally only the best projects are moving forward, but even there we can see mixed results.
Due to the upcoming shortages of < insert critical mineral > we need more exploration and more discoveries. Given the number of idle feasibility stage projects now, who is to say that these new discoveries won’t see the same roadblocks that the current projects are seeing. Real mining is a tough business – doing studies isn’t.


Inferred resources represent the lowest confidence category of mineral resources; typically estimated in zones with limited sampling and unconfirmed geological continuity. They carry the highest geological uncertainty of the three resource categories.
Companies sometimes will commence the permitting process based on their PEA study. There are some risks to doing this, and the Inferred resource creates one of these risks.
Let us examine some specific aspects of permitting that can be influenced by Inferred resources.
Inferred resources present a unique paradox; they can and can’t be used in mining economic analysis. They can be used to examine project viability but can’t be used to make a production decision.
Junior mining companies and Tech Startups share numerous similarities, although they operate in very different worlds. The following comments should recognize that junior mining ecosystem has been around for generations, long before the birth of tech ecosystems.
Exploration spending shares some of the same characteristics of more commonly R&D.
Another similarity between junior mining and tech world is in the way early-stage viability is assessed. This is required to decide whether millions of dollars of further investment is warranted. Miners will complete a PEA. Startups will complete Product-Market Fit research.
Recently I have been reviewing a few mining projects from an investor’s perspective. This led me to wonder whether junior mining companies should share more than just their drill hole highlights. What about the raw assays? A mining company announces highlighted drill intervals, but what exactly do those numbers represent?
There is a sense that many mining investors are becoming more sophisticated, and they want to fully understand the exploration process.
1. Misinterpretation & “Amateur” Experts: One risk is that someone with a very basic understanding of mining software and limited understanding of the local geology, runs flawed interpretations and publicizes their incorrect conclusions. A company may find that correcting false narratives publicly can be harder than preventing them.
Once the assay data is public, it may be more difficult for a company to manage the story. A press release lets them frame results in the context of their business plan; a raw data file does not.
For investors trying to assess a junior explorer, or geologists conducting a technical review, or a regulator trying to ensure fair and accurate disclosure, access to raw assay data can play a part in promoting good judgment and accurate disclosure from companies.
I recently noticed a few new mining studies that relied on toll milling as their base case operation. This made me wonder if this is a trend and if there are more examples of where this is happening.
USER PROMPT: What are the risks of toll milling plan.
RESPONSE: The Qualified Person (QP) signing off on a technical study that uses toll milling as the base case carries significant professional and regulatory responsibility, particularly under NI 43-101 in Canada or JORC in Australia.
The results given by Claude are quite thorough and insightful. It’s hard to argue with its observations and conclusions. This research took all of 30 seconds, so I can see it is no longer difficult to become a blog writer. Writing isn’t the challenge; finding interesting topics is.
The lesson is that QP’s signing off on technical information for clients should be proficient in the nature of their work and need to know the reporting rules very well. Some of these incidents involve error and poor judgment, not outright fraud.
43-101 regulations state that “An issuer must not file a technical report that contains a disclaimer by any qualified person responsible for preparing or supervising the preparation of all or part of the report that
This ends Part 2 of this blog post. It hopefully highlights the importance of QP’s being knowledgably on the disclosure rules and the technical aspects of what they are hired to do.
The focus of this blog is on the types of activities that raised the red flags in the past. I am less interested in naming the people responsible, although the associated web links do provide more detail on the events.
This ends Part 1 of this blog post. Part 2 will continue with a few more examples, specifically involving Qualified Persons, and can be found at this link 
So, you just completed your initial PEA cashflow model and the resulting NPV and IRR are a little disappointing. They are not what everyone was expecting. They don’t meet the ideal targets of an IRR greater than 30% and an NPV that is more than 2x the initial capital cost. The project could now be on life support in the eyes of some.
The discounting of cashflows in a cashflow model means that up-front revenues and costs have a bigger impact on the final economics than those far off in the future. This effect is amplified at higher discount rates.
ake to the cashflow model. Sometimes several of the small ones, when compounded together, will result in a significant impact. Here are some of the other cashflow model adjustments that I have seen.
Don’t let a disappointing NPV get you down. There may be a few ways to boost the NPV by applying some common practices. However, if after applying all of these adjustments, the NPV still isn’t great, something bigger may be required. That could be an entire project scope re-think.
Two dilution approaches are common. One can either construct a diluted block model; or one can apply dilution afterwards in the production schedule. I have used both approaches at different times.
Sometimes lower grade stockpiles are built up by the mine each year but only processed at the end of the mine life. Periodically the ore mining rate may exceed the processing rate and other times it may be less. This is where the stockpile provides its service, smoothing the ore delivery to the plant.
Once the schedules are finalized, they are normally reviewed by the client for approval. The strip ratio and ore grade profile by date are of interest. One may then be asked to look to at different stockpiling approaches to see if an NPV (i.e. head grade) improvement is possible.
The last task for the mine engineer in Chapter 16 is estimating the open pit equipment fleet and manpower needs. The capital and operating costs for the mining operation will also be calculated as part of this work, but the costs are only presented in Chapter 21.
The support equipment needs (dozers, graders, pickups, mechanics trucks, etc.) are typically fixed. For example, 2 graders per year regardless if the annual tonnages mined fluctuate.
These two blog posts hopefully give an overview of some of the things that mining engineers do as part of their jobs. Hopefully the posts also shed light on the amount of work that goes into Chapter 16 of a 43-101 report. While that chapter may not seem that long compared to some of the others, a lot of the effort is behind the scenes.
So I thought what better way to explain the mining engineer role than by describing the anatomy of a typical Chapter 16 (MINING) in a 43-101 Technical Report. That chapter is a good example of the range of tasks typically undertaken by mining engineers.
There is always a mineral resource estimate available before doing a PEA. The way the resource is reported will indicate what type of mine this likely is. The geologists have already done some of the mining engineer’s work.
Before starting pit optimization, we require economic inputs from several people. The base case metal prices must be selected (normally with input from the client). The mining operating cost per tonne must be estimated (by the mining engineer). The processing engineers will provide the processing cost and recovery for each ore type.
Once the optimization is run, a series of nested pit shells are created, each with its own tonnes and grade. These shells are compared for incremental strip ratio, incremental head grade, total tonnes, and contained metal.
The mining engineer is now ready to undertake the pit design. The pit design step introduces a benched slope profile, smooths out the pit shape, and adds haulroads. Hence a couple of key input parameters are required at this time. The mining engineer will need to know the geotechnical pit slope criteria and the truck size & haul road widths. Let’s look at both of these.
Ramps: Next the mining engineer needs to select the truck size, even though the production schedule has not yet been created.