Heap leach operations have long occupied an unusual space in the mining industry — treated more as process infrastructure than high-consequence mine waste facilities, and historically subject to far less scrutiny than tailings storage facilities. That is changing rapidly.
Writing for the AusIMM Bulletin, SRK Consulting's Heather Thomson, along with author Jamie Wade and contributors Breese Burnley and Aaron Debono, examine why heap leach governance is emerging as one of mining's next major operational risk frontiers — and what the industry needs to do differently.
A combination of high-profile global failures, growing investor awareness, and tightening governance expectations is forcing a rethink of how heap leach facilities are designed, operated, and monitored across their full lifecycle.
Heather, a principal civil engineer in SRK's tailings group, highlights a fundamental gap in the Australian context: there are currently no dedicated guidance documents or standards for heap leach facilities in Australia. Projects are instead borrowing frameworks from tailings and waste rock management, making outcomes highly operator- and designer-dependent. While highly prescriptive regulation isn't always appropriate for inherently site-specific facilities, the absence of a mature governance framework creates significant variability in design standards and oversight expectations.
Central to the discussion is the role of water. As Heather puts it plainly: "Water drives everything." Seepage, saturation, liner performance, and downstream consequences are all water-dependent variables — and recent global failures have demonstrated that the assumption of lower risk in heap leach operations due to reduced water volumes can lead to dangerous complacency.
The article draws on two significant international failures — one in Türkiye and one in Canada's Yukon — as inflection points that are reshaping industry thinking, much as major tailings failures drove the development of the Global Industry Standard on Tailings Management (GISTM). A recurring theme is that failures rarely stem from a single design flaw, but rather from a long history of expansions, ownership changes, and accumulated operational modifications that erode corporate memory over time.
One of the strongest recommendations to emerge is the adoption of an Engineer of Record (EOR) model for heap leach facilities — continuous, independent technical oversight across design, construction, operation, and closure. The panel is also clear that closure planning can no longer be an afterthought. As Breese notes, facilities designed purely for short-term operational efficiency often create long-term liability — and planning for closure from the outset is ultimately cheaper.
The article also contrasts Australia's emerging governance landscape with Nevada's more mature regulatory environment, where minimum design criteria, closure planning requirements, and site-specific flexibility have been developed over decades of operational experience.
On the technology front, the growing availability of real-time monitoring data — from drone surveys to automated stability systems — is welcomed, but the panel urges caution against over-reliance on remote monitoring. Heather is clear that physical site presence remains irreplaceable: "When you go out there and touch the dirt, you learn an awful lot."
The overall message is straightforward: heap leach facilities carry the same lifecycle, stability, and governance risks that transformed tailings management globally. The industry's mindset is beginning to shift — and for those willing to invest in independent oversight, rigorous design, and genuine closure planning, the path forward is well-defined.
Read the full article from AusIMM Bulletin here.
