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The mining industry is confronting a less visible but increasingly critical threat as mining operations push deeper and geological conditions grow more complex, which is reactive ground and elevated blast-hole temperatures. These conditions are redefining how mines approach safety, demanding more rigorous science, tighter controls and continuous validation across the life of an operation.
BME is positioning itself at the forefront of this shift, supporting mining companies with practical, science-led solutions designed to improve blasting performance while safeguarding personnel in high-risk environments. At the core of this approach is the recognition that reactive ground is not a static challenge. It evolves as mining progresses, often without obvious warning, requiring constant reassessment and adaptation.
The first step in managing risk lies in early identification. According to BME’s Reactive Ground Specialist, Victor Krause, blast holes are typically classified as “hot” when temperatures exceed 40°C or increase by at least 3°C during monitoring. “Elevated temperatures may result from coal seam fires, sulphide oxidation, geothermal gradients and other geological factors. Coal seam fires can generate temperatures exceeding 600°C and during active combustion, more than 1 000°C,” said Krause.
Temperature alone is not always a reliable indicator. Some of the most severe incidents occur in conditions that initially appear stable.
Krause cautioned that temperature alone is not always a reliable indicator of reactive ground. He noted, “Some of the most severe reactions occur in blast holes showing little or no evidence of elevated temperatures before charging.” Instead, mines must look for a broader set of warning signs including sulphide-bearing sediments, acidic conditions, corrosion, fumes, bubbling or unexplained changes in hole conditions.
BME’s response to these risks is grounded in detailed scientific testing and site-specific analysis. Through reactivity assessments, inhibitor requirement determination and sleep-time validation, the company helps mines tailor explosive formulations and procedures to their unique geological conditions. “Site-specific reactivity assessments, inhibitor requirement determination and sleep-time validation remain essential to ensuring safe blasting performance,” emphasised Nishan Hariparsad, General Manager at BME.
While inhibited emulsions play a key role in slowing reaction rates and extending safety windows, they are not a substitute for discipline and testing.
Hariparsad said, “They therefore complement, rather than replace, rigorous testing and disciplined operating procedures.” Temperature adds another layer of complexity. Elevated heat can affect both explosive integrity and initiation systems.
“Certain explosive components may begin to soften at temperatures of around 70°C, increasing the risk of degradation or premature initiation. Both electronic and non-electric initiation systems may also be adversely affected if conditions are not properly understood and controlled,” noted Hariparsad. He added that ammonium nitrate-based bulk explosives at “prolonged exposure to elevated temperatures can increase the likelihood of decomposition or ignition, particularly where reactive ground conditions are present.”
A key shift in industry thinking is the move away from one-off assessments towards continuous monitoring and validation. Hariparsad explained, “Reactive ground testing should begin as soon as reactivity is suspected and continue throughout the life of the operation. As mining advances into new geological domains, changing ground conditions may alter a site’s reactivity profile, requiring explosive formulations, inhibitor levels and allowable sleep times to be continuously validated.” This lifecycle approach reflects the reality that risk conditions can change rapidly as new areas are exposed.
Beyond technology and testing, safe blasting ultimately depends on strict operational discipline. BME advocates a stop-work approach whenever uncertainty exists around temperature, reactivity or product suitability, ensuring that risks are reassessed before operations continue. “Safe blasting also depends on maintaining confidence in the predictability of the entire blasting process,” noted Hariparsad.
Clear protocols are essential in high-risk scenarios. Once a reaction begins, intervention is no longer an option. He added, “Once a reaction has started, exclusion zones and emergency procedures must be implemented immediately.” Krause reinforced this point, stressing that under no circumstances should personnel attempt to remove explosives or recharge a reacting hole.
The potential consequences of misjudging reactive ground are stark. In one monitored case, emulsion-loaded soil samples gradually increased in temperature from 32°C to 178°C over several days before entering thermal runaway. Within just 19 minutes, temperatures surged to approximately 800°C, resulting in ignition. The example underscores the unpredictable nature of reactive ground and the importance of early detection and continuous monitoring.
As mining moves into increasingly challenging environments, the margin for error continues to narrow. Managing reactive ground is no longer a niche technical concern but a central pillar of operational safety and efficiency. By combining scientific testing, tailored product solutions and strict procedural controls, BME is helping to raise the standard for safe blasting in modern mining. In an industry defined by risk, the ability to anticipate and manage the unseen may prove to be one of its most valuable capabilities.
