By Lesley McGilp, Executive Director, IMII; and Craig Funk, Director, GeoServices & Land, Nutrien & IMII Board Member
This article was prepared for publication prior to the December 2025 ground-fall event at the Esterhazy K3 mine that took the life of a member company employee. The authors wish to acknowledge the tragedy and that of other miners who have lost their lives in the line of duty. This incident emphasizes the importance of continuing efforts to improve mine safety so all miners can return home safety to their families at night.
The International Minerals Innovation Institute (IMII) is a member-based consortium that facilitates collaborative innovation and workforce development to advance the Saskatchewan mining sector. IMII’s focus areas include safety and the consortium has a number of cutting-edge initiatives focused on improving safety from hazards posed from the rock itself.
One of the hazards of any underground mining operation is rock stability and especially “back” stability (aka the mine roof). Figure 1 illustrates this hazard.
While mining machines, processes, and operating procedures are designed to mitigate risks to people and equipment from back falls, improved knowledge and technology can further reduce risk. Potash is a ‘soft rock’ that behaves viscously, causing it to ‘flow’ in response to induced stresses. Saskatchewan potash mines employ stress-relief mining techniques, which use “short-term sacrificial mine rooms to draw mining-induced high horizontal stresses away from nearby long-term entries”, according to the article “How geoscientists are making potash safer”, which can be found on the CSEG website. Clay seams, which are found in the Saskatoon area mines, require extra diligence because they are zones of weakness. The Shadowband clay – a distinct geological marker within the Lower Patience Lake salt beam (aka B-Zone) – is poorly understood. As such, operators excavate this layer, along with adjacent extra sub-economic material to mitigate roof failure risks. The Shadowband clay is a subdued and a rather subtle feature which is how the name ‘Shadowband’ was coined.
University of Regina professor Dr. Leslie Robbins is working with a team to identify characteristics of the Shadowband clay that may contribute or lead to roof collapses in the Patience Lake B zone. The U of R team will review data from funders Nutrien & BHP (Mitacs is also a funder), including geophysical data, mining reports, core photos, and borehole logs. Statistical techniques will be used to identify the key contributing factors to roof collapse and then seek to identify optimal measurement methods to monitor those factors.
IMII also has other projects underway exploring underground measurement and sensing techniques to detect ‘beyond the mining face’. A completed project explored mining-induced micro-seismicity with Nutrien and Western University, and a current project with University of Saskatchewan funded by Nutrien, Mosaic, and BHP is building on this work by examining the mechanical behaviour of pillars under variable mining and geological conditions in potash mines. Mitacs/NSERC contributed funding to both projects. Saskatchewan Polytechnic and the Southern Alberta Institute of Technology recently began a project to identify the most promising electromagnetic frequency ranges for imaging beyond the visible surface of the boring face. The goal of the work is to enable future development of an imaging system for field use. The project is supported by Nutrien and BHP, and falls under the P2inacle program co-funded by PrairiesCan.
Ground Penetrating Radar (GPR) tools developed for Saskatchewan potash operations presently provide real-time measurements of salt-beam thickness, which are used to warn operators about potential thinning of this layer. While GPR technology has been a great success, further innovations could further improve mine safety. Presently, IMII members Mosaic and BHP are contributing funding to a system under development by Saskatchewan’s Ambitionner AI Solutions. Known as AmbDrift, it will integrate AI-powered visual inspection and analysis of non-visual data, such as stress and movement within geological formations, collected through a network of sensors. The system will identify visible and invisible defects, prioritize areas needing attention, and recommend timely remedial actions without interrupting daily operations. This project is co-funded by IRAP/SAIF and Ambitionner with in-kind from Sasktel.
The described projects involve IMII member contributions of $627,000 cash and $116,000 of in-kind contributions, which, with additions from other funders acknowledged above, involves a total budget of $1.68 million. The projects take place from 2020 to 2028 and involve over 36 researchers and industry collaborators. IMII’s work in this area is increasing the collective knowledge of the Saskatchewan mining innovation ecosystem that drives innovative advancements to improve underground potash mining safety.
