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By Aiden Carey, Jim Kennedy

During December 2007, Lake Cowal Gold Mine located in New South Wales, Australia experienced a significant pit wall failure. The wall failure resulted in the deposition of a large quantity of saprolite consisting largely of clays and lake bed sediments to the bottom of the Phase 1 open pit mine. This wall failure ultimately buried two loaded blast patterns.

Jan 1, 2011

By Dale S. Preece

The blast-induced movement and final location of geologic layers that may cause environmental problems can be predicted using discrete element methods. This prediction capability can be used by mine operators to locate the material in the muck pile during excavation which would allow encapsulation to prevent groundwater infiltration.

Jan 1, 1994

By D T. Froedge

The latest development in vibration measurement equipment involves small microcomputer operated micro-sized seismographs. As the result of this there has been an explosion of the data generated by these systems. For example: ten micro-seismographs taking ten shots generate over 2.5 megabytes of data.

Jan 1, 1994

By Robert Hopler

The use of electrical fuzes is rapidly superseding the old cap and fuse method of firing blasts. It is therefore desirable that the details of this kind of blasting should be more generally understood

Jan 1, 2006

By H. Rossmanith

This contribution introduces the fundamental concepts of wave propagation and fracture mechanics which form the basis of electronic blasting, i.e. precise initiation timing using electronic detonators. The concept of Lagrange diagrams will be frequently used for the calculation of the delay time between blast-holes in a row and rows of blast-holes. The effect of burden and structural geology will be briefly touched. It is found that the advanced blasting technology based on the use of electronic detonators introduces a change of paradigm. It will be shown that knowledge in wave propagation and fracture mechanics is essential for the successful application of the new blasting technique in industry. In particular, the delay time, the wave speeds in the rock mass, the shape of the wave pulse and the acoustic impedance mismatch have become decisive parameters in advanced blasting. Utilizing the wave speed and wave shapes of detonations, large scale tests Utilizing the wave speed and wave shapes of detonations, large scale tests in various countries (Australia, Chile, etc.) have shown that optimal delay timing requires shorter delay times in conjunction with allowing for a wider drilling pattern and the use of a reduced amount of explosives, i.e. a lower powder factor. This seemingly contradictory arrangement is fully justified by using scientific principles in blasting, and converting blasting from an art to a scientific discipline.

Jan 1, 2003

By Gabriel Gonzalez, Paulo Couceiro, Luis Manriquez, Alejandro Gutierrez, Juan Navarro

A high-stakes blasting campaign was successfully executed at a major open pit copper mine in northern Chile. This operation posed a significant technical challenge due to its immediate proximity to the tailings dam - a critical infrastructure whose structural integrity depends on strict control of blast-induced seismic vibrations. The geological complexity of the area, characterized by upper andesite interbedded with caliche (carbonate), further complicated the operation. This lithological composition, known for its high tenacity and cohesion, posed additional challenges for achieving effective fragmentation, necessitating a highly customized blast design and loading strategy. The campaign included four production blasts and one secondary blast, all executed under the constraint of not exceeding the Peak Ground Acceleration (PGA) threshold of 0.64g, as defined by the Maximum Credible Earthquake (MCE) scenario. To ensure compliance, geophones were strategically installed at three monitoring points (P1, P2, and P3) on the dam to capture real-time acceleration data. The use of specialized blast patterns, precise stemming control, and electronically sequenced detonations ensured that all recorded accelerations remained well below the critical threshold. A total of 496,163 tonnes of material were safely blasted, with 8,452 meters drilled and powder factors ranging from 419 to 594 g/ton. Therefore, this case study exemplifies operational excellence in controlled blasting, demonstrating the feasibility of safe mining near geotechnically sensitive zones through predictive modeling, rigorous QA/QC, and post-blast analysis.

Jan 26, 2026

By R F. Hoeberling

"The use of ground penetrating radar (GPR) for geological purposes has been underway for almost two decades. The commercial need for a versatile GPR that can rapidly identify buried objects andunderground voids has been recognized and is an area of research that has already proved useful for several geological activities. Several types of GPR endeavors have been reported in the literature, including exploration of placer deposits (Davis, et al. 1985) and heavy metals (Hammond and Sprenke, 1991), improving oil recovery (Witterholt and Kretzschmar, 1984), investigating coal seams (Coon, et al., 1981), stratigraphic survey (Fisher, et al. 1992), Lunar soils characterization (Olhoeft, et al. 1975 and Strangway, et al. 1977), characterization of rock around mine tunnels (Cook, 1985), location of old mine workings (Scaife, et al., 1992), location of abandoned gas wells in coal seams (Kemerait, 1992) and survey of hazardous waste burial areas (Horton, et al., 1981). Coal seammapping has been developed using a related continuous wave, phase discrimination technique (Stolarczyk, 1990). As the technology for the radar equipment and the onsite computational power has increased, many new applications have become feasible. This article will describe the present status of the GPR technology and indicate some of the exciting possibilities for nearterm prototypes now being constructed."

Jan 1, 1994

By Steven D. Knudsen, Dale S. Preece

Computer modeling of the blasting process can aid in gaining an understanding of the physics controlling the process. The sequence of events in a blast occur so rapidly and in such a violent environment that measurements are still difficult to obtain. Computer modeling using a program such as DMC [Taylor and Preece, 1989a, 1989b] can provide insights into the physics of the rapid and violent events associated with a blast. DMC has been used to simulate crater blasting @‘teece, 199Oc] and the blasting of Oil Shale for modified in-situ retorting [Freece, 1990a, 1990b]. This paper will address the influence that damping has on the velocity distribution in the rock mass during the rock motion phase of a blast. Since velocity distribution is a controlling factor of muck pile shape, damping also conbibutes to muck pile shape.

Jan 1, 1992

By Thomas C. Palangio

Since the advent of explosives, people have been trying to mechanize the process of loading it into long, narrow holes. Automated loading frees manpower from the arduous task of charging granular, cartridged and slurry explosives. An unexpected bonus of the automation process has been the realization of some valuable side effects such as high throughputs which speed up the loading process and higher loading densities which enhance explosive performance and permit hole patterns to be expanded.

Jan 1, 1990

By C. Morel, P. Fredes, L. Rojas

This article presents a comprehensive study on the development and application of the specific module called "Exclusion Zone" created by Orica to determine blast evacuation exclusion zones. This module, integrated into the "SHOTPlus™ (blast design software)" software, has been used in the context of optimizing equipment evacuation exclusion zones in a northern Chile mine. The main objective has been to reduce the travel times of extraction equipment without compromising the safety of individuals. The module considers various factors such as the explosive charges used, stemming, sector topography, and detonation sequence to determine the rock projection generated by the blast. Furthermore, it utilizes information collected by drones and support tools such as Groundprobe and BlastVision™. The results obtained demonstrate that the use of this technology has allowed the optimization of blast evacuation distances in the northern Chile mine, generating significant economic benefits for the client.

Jan 1, 2024

By Lon Santis

This paper analyzes 110 serious accidents that occurred during the use of commercial explosives in mining, construction, and other industries since 1992. Data from the Mine Safety and Health Administration (MSHA), the Institute of Makers of Explosives (IME) members’ reports, and media reports were used. Only accidents that resulted in a fatality, significant lost work time, or injury to the public were considered in this analysis. The accident data were analyzed for trends in frequency, type of industry, cause, type of individual harmed, and geographical region. Although the data showed that explosives accidents are decreasing in frequency, still, 29 people were killed and 134 injured. Eightyfive of the accidents occurred in mining, 17 occurred in construction, and 8 occurred in other industries including oil recovery, seismic exploration, agriculture, logging, boiler cleaning, and avalanche blasting. As other studies have shown, flyrock and failure of blast area security caused over half of the accidents. Mishandling, misfires, or fumes caused just over one-third of the accidents. Lightning and drilling into explosives were responsible for the remainder of accidents.

Jan 1, 2003

By Bruce Notthup

Using a Three Dimensional Laser Profiler, persomrel from Austin Powder were able to determine drilling patterns for use in underground mine Room and Pillar blasting operations, The faces had got out of alignment, causing concave faces across the 100 feet wide, 28 feet high tunnels. This was leading to poor drilling and poor blasting results. By profiling the faces, modifications could be made to the drilling pattern to help gradually straighten the faces. The Laser Profiler was also used to check the accuracy of collaring the holes and also perform post blast surveying of the positions of the bootlegs. This allowed recommendations to be made to improve drilling operations at the face. In addition, other volumetric calculations could be performed using the systems’ surveying software, all a lot more easily and quickly than by standard methods.

Jan 1, 1994

By V. Wetzig

In the past, various investigations have been carried out at the Hagerbach Experimental Gallery under accurately reproducible conditions, in order to determine the emissions emanating from blasting operations. Comparative investigations proved that the composition of the blast fumes is influenced by the choice of different explosives. It also emerged that the use of emulsion explosives leads to significantly lower concentrations of harmful substances in the blast fumes. Further investigations concerned the residues and reaction products from the explosive process which are left in the debris. Eluate tests on representative samples of debris were used to determine the concentrations of nitrate, nitrite and ammonium in the debris.

Jan 1, 2001

By Larry Schneider

In 1998, the Blast Vibration and Seismograph Section of the International Society of Explosives Engineers formed a working group to collect and compile a list of regulations limiting ground vibrations from blasting. The goal was to locate those countries, states, provinces, and cities that have such regulations, identify which governmental body enforces them, and determine what limits on ground vibrations are imposed upon the blasting operations. In the course of this study, data was collected from over 60 jurisdictions where peak particle velocity restrictions range from non-existent to very stringent. Some of the regulations were found to be based upon standards grounded in good science, while others possess little or no technical justification. This presentation will summarize the findings of the subcommittee, focusing primarily on what the limits are, which type of blasting operations must adhere to them, and to what structures they apply. The degree to which these regulations are based upon valid scientific and engineering research will be discussed. A listing of specific locations having such regulations and information about those regulations will be provide

Jan 1, 2000

By Yeon-Ho Jin, Eui-Haeng Heo, Yun-Seok Park, Sung-Oong Choi, Hyung-Dong Min, Min-Su Jeong, Seung-Joong Lee

As rock fragmentation in bench blasting can affect the following process such as loading, hauling and crushing, its good control is essential for assessment of blasting efficiency and production cost.

Jan 1, 2015

By Timothy Stark

Blasters are usually strictly liable for injury or damage caused by flyrock (trespassory invasion) and blast-induced vibrations (non-trespassory invasion). The application of strict liability to non-trespassory invasions has resulted in significant litigation that has hampered the use of blasting and the blasting industry. Stark (2002) proposes that blasters should not be held strictly liable for non-trespassory invasions but should be liable only if their conduct is proven to be negligent. This change in legal standard was proposed because improvements in blasting technology over the last thirty years allow blasting to be conducted without substantial risk of harm to property and thus the amount of harm imposed by a blast can be related to the level of care exercised by the blaster. It is anticipated that a negligence standard will reduce the amount of litigation because a plaintiff will have a greater burden to overcome. To facilitate the acceptance of a negligence standard by a court of law, this paper summarizes the standard of care using the 1977 Surface Mining Control and Reclamation Act, extensive U.S. Bureau of Mines research, and current blasting techniques, such as blasting mats. It is important for the blasting industry to promulgate a standard of care so a judge can feel confident that blasting can be routinely and systematically controlled and if the legal standard is changed from strict liability to negligence a subsequent judge or jury will be able to evaluate the level of care exercised by the blaster. This paper also suggests that the industry and/or ISEE develop and disseminate a comprehensive standard of care that courts can use to further justify a change from strict liability to negligence and evaluate the standard of care.

Jan 1, 2003

By David A. Bacca

Hydraulically powered submersible borehole dewatering pumps and emulsion/ANFO blends evolved at about the same time and for the same reasons. Mining operators needed safe, efficient dewatering systems and water resistant products.

Jan 1, 1994

By Steve Dillingham

In every aspect of conduct, on the blast site or off, the issue of credibility is raised. Promises are made, commitments are satisfied, safe practices are obeyed, communication is maintained, and proven procedures followed. Only by fulfilling these objectives, are we deemed trustworthy and reliable - in other words - credible. Unfortunately, at times, we fall short of achieving our goals. Whether intentionally or accidentally, everything is not completed according to plan or accuracy. On the blast site, falling short of achieving such goals may contribute significantly to a chain of events that can potentially produce accidents. At the very least, a blaster’s credibility will be jeopardized. The fact remains that the blaster that continuously conducts business in a professional manner will less likely find him or herself as a defendant in future claims.

Jan 1, 2003

By John W. Gunnett

The purpose of this afternoon’s presentation is to highlight the investigative proce dures employed to complete an engineering audit of a mining operation. Skelly and Loy has been retained to perform operational audits throughout the nation’s coal fields, The need for such studies is generally associated with long term coal supply contracts and is typically initiated by the utility company. However, a number of projects have been commissioned by mining companies while others have been jointly funded by the utility and mining company.

Jan 1, 1992

By Harley Cheema, Brandon Fryman, John Tatom

A new magazine propagation model has been proposed by the IMESAFR Science Panel for eventual implementation into the IMESAFR QRA program. Initial results from this QRA propagation model are now available.

Feb 1, 2020