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By C. Zuniga, S. Combrinck, C. Peters

Agnico Eagle Gold have partnered with Enaex Australia at their Fosterville gold mine to leverage a combination of drill and blast technologies to optimise underground development mining. The mine is the first site globally to collaboratively develop and trial Enaex SWIFT electronic development detonators, which utilise a novel approach to the user interface, simplifying implementation and enabling the benefits of electronic initiation without the complexity of a conventional system. This has been combined with the use of a Sandvik 422i smart jumbo, and the Enaex underground emulsion charging unit with the capability to tailor the delivery of explosives as required and report on a hole-by-hole basis. The combination of these technologies enables full engineering oversight of the development cycle, in turn enabling optimisation of this process in a historically conservative application. The methodology for leveraging these technologies is to bore a controlled and defined blast pattern through using a smart jumbo, load the blast holes utilising lace loading to deliver a desired quantity of ammonium nitrate emulsion per hole, with the ability to reduce chargeweight for perimeter control, and utilising Enaex SWIFT electronic detonators with flexible template type pre-defined delays to initiate the blast holes. Subsequent to firing and excavation the performance of the blast in fragmentation, advance efficiency, and overbreak and underbreak is measured and reviewed. This is then used to optimise the development cycle and apply to other parts of the mine.

Feb 6, 2023

By E. Lentilucci, A. Dey, X. Liu, A. Datta, S. Ghosh

The segmentation of quarry blast smoke plumes is a crucial research area that has the potential to enhance safety, environmental monitoring, object detection, and regulatory compliance in the mining industry. Smoke plume segmentation can be used to identify the spatial extent and temporal evolution of smoke plumes generated by the blast. This information can be used to improve the understanding of blast dynamics and optimize blast designs. Furthermore, smoke plume segmentation can assist in identifying potential environmental and health hazards associated with the release of smoke and dust particles into the atmosphere during quarry blasts. However, many current smoke plume segmentation algorithms are designed for segmentation of smoke plumes from fires and are not suitable for segmentation of plumes from quarry blasts. The proposed method in this paper leverages the video frame captured before the blast as a stationary background image, which helps to reduce other confuser objects present in the image along with a selfadaptive clustering method. The color channels of the image are utilized based on the different contrast properties of the smoke, with a self-adaptive gradient compensation applied for edge detection of the smoke plume. This approach offers a novel and effective way to segment smoke in quarry blast analysis, with potential applications in the calculation of noxious gas volume and concentration within the plume. Compared to other algorithms, our method improves accuracy, decreases the false alarm rates, and reduces the overall miss rate. Overall, this paper contributes to the research on smoke plume image segmentation, particularly for quarry blast smoke plumes, which possess unique characteristics that require specialized algorithms for accurate segmentation.

Jan 1, 2024

By Khiva Haidar Shauma Tassno, Zulham Ahmad, Farhan Harist Maharesi, Abdullah Badawi Batubara

Blasting operations can use a bulk emulsion explosive (EE) with a formulation based on used oil as a replacement for refined fuel oil. The most commonly employed used oil for making EE is a mineral based used engine oil that passes an impurity content standard. It is known that not all types of used oil are easily incorporated into EE formulations. Impurities in used oil can disturb EE stability resulting in crystallization and phase separation and consequently led to poor detonation quality. In 2024, a poor blast result occurred at an Indonesian mine due to utilization of used oil that was not within specification. A research project conducted from February to April 2025 found that used transmission oil differs from used engine oil in hydrocarbon composition. Transmission oil contains more additives that affect EE stability due to polarity differences and the disruption of colloidal state stability. Lab tests including stress testing and crystal growth observation aided the development of a stable EE formulation based on used oil and used transmission oil. In mid-April 2025, blast evaluations were conducted using the EE that was formulated using used engine oil and used transmission oil. Measurements of velocity of detonation, fragmentation, and digging time, demonstrated high quality EE was produced. Application of used oil in EE revolutionized the capability of mining operations to improve blast sustainability and cleanliness. Through comprehensive research, robust testing, and effective supply chain management, it is possible to replace some portion of refined fuel oil with used oil without compromising blasting performance. The inclusion of used transmission oil broadens the overall used oil specification and increases the volume of recycled used oil available for blasting. The increased volume of used oil available can reduce the amount of waste generated by mining projects while maintaining operational efficiency.

Jan 26, 2026

By Chris Searing

An underground room-and-pillar limestone mine in Western Missouri acquired a new primary crusher, physically larger in every dimension than the unit it replaced. Due to the space constraints within the mine, resetting the truck dump and feeder to account for the larger crusher was unfeasible. Mine management determined the most practical solution was to increase the available area for the new crusher via blasting. Fitting the new crusher into the existing area required the removal of 6 feet (1.83m) of limestone from the original floor grade. Blast parameters had to be designed to effectively break this shallow depth of rock while controlling movement to avoid contacting the mine back 23 feet (7.01m) overhead, an apron feeder 13 feet (3.96m) above the southern extent of the area, and the original crusher which was still in place 15 feet (4.57m) from the first pattern. Additionally, work needed to be completed within an aggressive schedule set forth by the mine, allowing little room for delay or error. This paper will examine the efforts taken to safely and effectively blast the rock while protecting nearby equipment and integrity of the mine back. Subjects covered will include blast design, adjustments made to account for drilling and equipment-related constraints, and how seemingly small changes in load parameters can significantly impact performance with small-diameter blast design.

Feb 6, 2023

By J Deen, P Sterk, W Forsyth

Homestake Mining Company has made a firm commitment to develop a functional and cost effective perimeter blasting program. The goal of the program is to develop smooth, sound walls in all development ends. A good perimeter blasting method will improve safety, reduce waste rock handling, allow easier support installation and reduce scaling time. All the benefits will contribute to an overall reduction in total development costs.

Jan 1, 1997

By Thomas Palangio, Blessing Taiwo

Image-based fragmentation analysis is increasingly utilized in blasting operations to evaluate particle size distribution in a non-intrusive and efficient manner. However, the accuracy of optical granulometry systems can vary significantly with particle size. Higher precision is typically achieved for larger fragments, generally those greater than golf ball size when using drone-based orthomosaic analysis. In contrast, the detection and delineation of fine particles become less reliable due to constraints such as pixel resolution, particle overlap, and partial burial within the muck pile. This variability does not undermine the value of image analysis but rather highlights the need for a deeper understanding of its operational thresholds and the integration of complementary methods or calibration approaches to improve its reliability across the entire particle size distribution. Technologies such as WipFrag, originally developed in the 1980s, are designed to conduct in-situ fragmentation analysis within complex blast environments, where fines are often obscured by larger fragments. The challenge becomes more significant in blast rounds exhibiting wide gradation ranges and increased fines, particularly resulting from excessive energy concentration in high-pressure zones near the borehole. Previously, this issue was addressed through methods such as analytical correction, zoom-merge correction, and empirical calibration using Rosin-Rammler and Swebrec distribution models. However, these traditional empirical calibration approaches, particularly those tied to distribution functions like Rosin-Rammler have shown limitations, especially in accurately representing the fine region of the fragmentation curve. In contrast, the recently developed xP-fan model, which incorporates the relationship between powder factor and fragment size, introduces the fragmentation energy fan principle which Kuz-Ram model does not entail. This paper presents a study on the application of the novel xP-fan calibration to enhance the accuracy of optical granulometry systems. The findings demonstrate how xP-fan help calibrate the fine region of the PSD without deflecting the maximum size.

Jan 26, 2026

By AK Chakraborty, AK Raina

Burden of drill hole is third most sensitive parameter effecting the ground vibration in blasting apart from maximum charge per delay and distance. Various types of burdens can be seen in practical bench blasting situations. Burden can be expressed as drilled burden and initiation burden. Drill holes may have various front row burdens (toe burden), which may be different from the designed burden. In order to ascertain the impact of front row burden as well as the initiation burden on intensity of ground vibration and air overpressure experiments were conducted in sandstone overburden benches of an opencast coal mine and limestone quarry. Blast trials were carried out in cognisance of both drill and initiation burden while keeping all other parameters constant. Effect of front row burden was also extensively studied by keeping almost all other parameters constant. The results of the study reveal that there is substantial influence of front row burden on the vibration and air overpressure. The statistical analysis of vibration and air overpressure data with drilled burden and initiation burden gives significant evidence that the level of peak particle velocity of vibration (Vmax)) is reduced by reducing effective burden with modification of initiation. Data analysis carried out for air overpressure versus initiation burden shows that reducing effective burden with modification of initiation results in increasing the level of P. The study reveals a qualitative assessment of the influence of burden on the blast induced vibration and air overpressure. The study also recommends to modify the initiation pattern to reduce the effective burden in order to reduce the vibration, without disturbing the fragmentation.

Jan 1, 2004

By César Ugaz, Jorge Cardenas

Mitigating the vibrations resulting from a blasting rocks is one of the most common challenges that Peruvian mining has, since if this impact is not mitigated it can generate discomfort and altercations with neighboring communities and also puts the continuity of the mining project at risk. In that sense, we must establish control parameters to mitigate these effects as much as possible. As a starting point we must establish areas of interest that in this context would be the communities near the mine; first stage to carry out constant monitoring at these points, the registration of vibrations and noise is vital for the success of this control, with this information we can establish predictive models, the registration of elemental waves and the evaluation of human perception. In a second stage, this information allows us to make decisions in engineering such as the selection of delay times, elaboration of detonation sequence schemes, maximum amount of operating load per delay window, as well as the use of special load designs (Decks). There is a fear that these controls generate negative impacts to the process, referring to fragmentation, dig rate, throughput, etc. Since we limit the explosive load necessary for the results we need. To avoid this we use "Decks" type load designs under a sequencing between these under time calculations by elemental waves, which generate a reduction in vibrations up to 50%, also complying with strict regulations without affecting the power factors to comply with our performance indicators. Finally, in a third stage we must carry out a constant evaluation of results according to the progress of the mine.

Jan 26, 2026

By M R. Hettigner, J Nawrocki, C E. Johnson, P G. Cahill

This study evaluates the effects of both short inter-hole and intra-hole delay times on rock fragmentation and throw. Full-scale test blasts were analyzed at a granite quarry in Talbotton, GA. This analysis provides a representative understanding of timing effects on fragmentation in the field, different from previous lab scale studies that negate the effect of geology. Inter-hole delay times between 0 ms and 25 ms were tested on a series of 4 bench blasts and subsequently examined using photographic fragmentation analysis methods.

Jan 1, 2017

By P. Ravanal, J. Blazquez, F. Ortega, P. Couceiro, J. Navarro

Massive blasting technique is an interesting alternative to optimize mining’s performance by enhancing digging rates and overall operation’s activities, especially when a reduced operational bench width is available. The exploitation of a huge bench through multiple blasts would mean a potential reduction in productivity and higher operational difficulties. In such hard circumstances, combined with complex geotechnical conditions, a full ground vibration analysis for near and far field vibrations are required in order to safely design and conduct the blast. In this paper, a comprehensive case study will be discussed to show how the application of massive blasting techniques was safely implemented in very complex geotechnical conditions. The proposed solution was based on performing a full ground vibration study to optimize blast design parameters, such as charging and timing, in order to fire the complete bench blast in a single shooting event, without compromising the slope stability. Thus, a massive blast with an approximate tonnage of 6.0Mt was successfully designed and blasted, attending all safety and stability criteria defined by the geotechnical and drilling and blasting departments of Minera Escondida.

Jan 1, 2024

By Z X. Zhang

If the iron ore loss is 15% in the process of mining, the total iron ore loss in the world will be about 461 million tons, this is equal to the total production of 230 iron ore mines each of which produces 2 million-tons of iron ore per year. Based on a series of blast tests in the Malmberget mine, this paper shows that ore recovery can be markedly increased by improving blasting technology such as choosing a correct primer position and making use of shock wave collision. The paper further suggests that a high ore recovery can not only reduce natural resource loss and mining cost but also prolong the life of a mine. In addition, the paper shows an example of reducing blast-caused rock damage in the roofs and walls of underground drifts (tunnels) by using new blasting methods in the Malmberget mine. Finally, the paper shows how the Malmberget mine has successfully reduced the ground vibrations, without adversely affecting fragmentation and ore recovery in sublevel caving mining.

Jan 1, 2014

By Walter Voglauer, Elisabeth Zechmeister

Five serial photos show the first second of the demolition of a 75 m high, reinforced concrete tower in the 23rd District of Vienna, Austria. The tower demolition with high explosives was necessary because a 175t excavator could not finalize the destruction with mechanical tools. All mechanical works in preparation of the blast, such as the borehole drilling, were done by civil companies under the responsibility of the contracted demolition company PRAJO. The blasting itself was planned and executed by the engineer corps of the Austrian Armed Forces, Sunday, May 26, 2013. Nearly 800 boreholes filled with more than 100 kg of military plastic explosives were initiated with about 1,600 Austin electric delay detonators in exactly 1,000 ms and 30 steps of delay. The 10,000 tons of reinforced concrete tower fell as planned without any damage to the environment. Photo 5. The rest of the detonators initiate the water pools filled with high explosives forming a bizarre white water front to fight the following strong development of dust. The first 1,000 milliseconds are over.

Jan 1, 2015

By Jack Eloranta

Proper selection of stemming has a profound effect on blast performance. This paper describes several methods of evaluating stemming performance in 16-inch blastholes. Tests are done on stemming ranging in size from nominal 1/4" crushed rock up to railroad ballast size rock (2 1/2" > diameter < 3/4"). Concrete plugs (both pre-cast and poured) are evaluated as well as air decking.

Jan 1, 1994

By Ronald Ticona

Generally, the drilling and blasting operation are managed independently to the processing plant outcomes. Therefore, the technical segmentation to determinate the ore drill and blast designs do not include processing plant rock properties such as Bond Work Index, Axb, Drop Weight Index or other. This work describes the case study of a copper mine in Peru, which, together with its strategic partner ORICA, have implemented projects focused on optimizing mine fragmentation. The year 2021, mine operation according to its mine plan would have a significantly increased SAG mill hardness, which would impact directly on copper concentrated production. An integrated strategy from mine to plant has become necessary to maintain the production levels.

Feb 6, 2023

By Michael S. Wieland

Delay detonators that are damaged by cross-hole wave interactions degrade blasting work and raise the risk of incidents. Damaged detonators impose risk, because they can retain sensitive explosives that respond to stray energy during recovery, inspection or disposal. Laboratory techniques were developed to rank the ruggedness of delay detonators under replicated field-shooting conditions. The hazards are tremendously magnified if trial detonators are installed directly in secondary explosives to rank initiation strength. Therefore indirect ranking techniques were sought that mitigate the risks without compromising the worthiness of the method. Four types of hardware fixtures, referred to as simulators, were developed to yield distinct forms of transient compression. The shock and rift versions generate compression pulses representative of in situ waveform components. The waiting time, until the trial detonator functions, duplicates typical delay periods. The trial detonator is mounted within water, which has a density and inertial resistance comparable to most blasting explosives. The work output from the trial detonator explosion is registered as fixture wall-expansion. This work output determines malfunction results, regardless of which type of simulator is used.

Jan 1, 1997

By Daniel Haines, Benjamin Konshak, Michelle Crull

American Technologies Incorporated Group (ATI) is the prime contractor with U.S. Army Corps of Engineers, Huntsville Center (CEHNC) in the Honolulu District for the removal of munitions and explosives of concern (MEC) at the Former Waikoloa Maneuver Area. The site is approximately 123,000 acres on the Big Island of Hawaii, which was used as an artillery firing range with live ammunition and other explosives deployed. ATI utilizes state of the art metal detection equipment to find and excavate metallic anomalies that have hazard potential. Both the investigation and disposal procedures present challenges due to residential communities and archeological sites that are located in and around the site. In order to excavate metallic anomalies safely and without adverse impact, ATI utilizes CEHNC-designed, open front barricades constructed of sandwiched sheets of aluminum with a support structure. When munitions or explosives are located, ATI is responsible for safe disposal using shape charge perforators to detonate the item where found. Sandbags are used for mitigating the effects of all detonations.

Jan 1, 2008

By Iván E, Alex Araya Jofre, Jean Guiroux Toro, Eduardo Valdés Guerra

Currently, it is important for companies to have controlled mining operations and adhere to production schedules. To achieve this, one of the key factors is maintaining high reliability in the P&T process, primarily the opening of ore stope, which could be delayed due to any unplanned or uncontrolled problem. These ore stope opening processes, whose main activity is generating free face, are a very important pillar for future mine planning. The possibility of ensuring their opening brings a series of downstream benefits: safety, economics, productivity, and compliance and adherence to plans. The process under discussion consists of developing free faces in a single blasting event. This will help us leverage greater reliability for overall production operation plans, reduce construction times, and open up opportunities for downstream improvements in the production process, considering technical factors in P&T designs. This study presents a developed methodology and shows the results of its implementation in ten (18) single-event free face blasts. The analysis includes cavity geometry, geology, rock qualities, drilling deviations, and the blasting strategy implemented for each event. The methodology used considered material fluffing processes, the actual drilling trajectory, the initiation sequence, QA/QC during explosive loading, monitoring instrumentation (vibrations), and VOD recording, among others. As a result, out of a total of 18 free-face events blasts in a single event, 16 were successful and two achieved 90% efficiency, reducing the stope's production start-up time by 50% compared to current operations. By implementing free face blasting in a single event, there are savings in operating costs, increased productivity of the mining equipment, and improved adherence to production plans. For applications with greater heights of free faces, where blasting cannot be carried out in a single event, we should consider performing them in two stages using wireless detonators already available on the market for mining operations.

Jan 26, 2026

By Jason Wilkinson

Drilling operations are a vital component of surface mining, directly influencing productivity, safety, and cost efficiency. This paper explores a multi-faceted approach to drill optimization, focusing on minimizing delays, and enhancing operational effectiveness. Key areas of inefficiency such as shift changes, fuel and water delays, and time lost between drilling holes are analyzed to identify actionable improvements. Equipment related factors, including the frequency of drill bit and drill steel changes, as well as the condition of deck bushings, are evaluated for their impact on downtime and performance consistency. Additionally, the integration of smooth drives and shock subs is examined for their role in reducing vibration related wear and improving drilling precision. Optimization of pattern approach strategies is highlighted as a means to reduce non-productive movement and align drilling with blast design more effectively. To support continuous improvement and accountability, the implementation of a driller scorecard is proposed. This tool enables the measurement of individual performance based on key operational metrics, fostering a culture of data driven management. Through a combination of field data analysis and best practice recommendations, this study provides a comprehensive framework for enhancing drilling productivity in mining operations. The findings aim to support mine operators in achieving higher efficiency, reducing operational costs, and extending equipment life through targeted optimization strategies.

Jan 26, 2026

By Claude Cunningham

AEL’s Electronic Delay Detonators are in routine use and growing in both volume and breadth of application in Africa. This trend will continue and grow internationally owing to increasing pressure on rockbreaking operations to conform to sustainable development principles. A fundamental breakthrough has been achieved, bringing production blasting into line with technologies, which leverage performance through tight monitoring and control. When moving from pyrotechnic systems, benefits are normally realized without having to adopt different timing patterns, but significant additional benefits are realisable by using the flexibility and precision of the electronic units to enter windows of timing previously closed. The higher price and increased care needed are a worthwhile investment, enabling operations to cross the chasm to stronger revenues, but the system must be robust and suited to the application and personnel. Economic models are vital for keeping track of the potential and achieved benefits of these systems. Some resistance can be expected from those who stand to lose income as a result of the improved efficiencies.

Jan 1, 2004

By Lon D. Santis

This paper reports on an evaluation of the safety characteristics of short lead, 5 centimeter (cm), Magnadet1 detonators. The Magnadet initiation system uses magnetic induction principles to transfer electric energy from the firing line to the detonator without a physical connection. This study was initiated because the Magnadet initiation system represents a new technology and the Bureau is interested in ensuring that no potential safety hazards are introduced into the nation's mining environment. The Magnadet system and its proper use are described along with a discussion of how it works. The potential hazards examined are: stray current from mine service power, lightning, DC current, static electricity, and radio frequency transmissions. Tip strength is also evaluated. Experiments were conducted to evaluate some hazards and theoretical methods were used to evaluate others. The results showed that the Magnadet short lead initiation system does not exhibit any unusual safety hazards. The new system is at least six times as resistant to common hazards as currently used electric initiation systems, so long as the insulation is intact.

Jan 1, 1992