Weighing up a potential project acquisition? During the due diligence phase, a thorough review of geotechnics and rock mechanics is critical to discovering opportunities… or fatal flaws.
Digging into source data from mapping, drilling and geologic modelling will uncover any geotechnical risks. When we look at source data, we ask:
• Has the data been collected in sufficient quantities to help us understand potential rock mass behaviour?
• How has the data been used when formulating the project design?
• How does the resulting design impact mineability, and does it introduce a lot of downside risk (or, on the flipside, potential upsides)?
Often, we run a mine design of our own to see how it compares to the design under review. Next, we assign a risk level to each design flaw, so as to understand if it could cause the entire mine to fail or merely impact mineability without compromising the entire project. From there, we make suggestions as to how to improve the design. In this phase we may require additional data collection and analysis; the more data at hand and the better its quality, the better the odds of helping the client reach a decision on whether to bid for the project or run away.
If the client decides to enter the bidding process, then the next stage is to use
the geotechnical data to help them estimate the value of the project. Key aspects to look at are:
• Slope design, which impacts strip ratio, among other things. If strip ratios get higher, this can lead to higher extraction costs and having to leave more resource behind.
• Design of benches and haul roads, because if these are constantly failing, it will have a substantial impact on operational costs.
• How much development is needed to commence production or upgrade the mine, as this will greatly impact capital costs.
Unfortunately, it is an all too common occurrence that a company will try to sell off a mine without providing sufficient geotechnical data. It would be easy to put this down to incompetence, but often when juniors are tight on money, the first thing they will cut back on is collecting proper data on rock mechanics and geotechnics. Whatever the reasons, inability to provide adequate geotechnical data should be a
deal breaker – because without it, you can not properly understand the inherent risks in a project.
