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By S. Evans, J. Phillips-White, D. Morton

The partnership between Orica and MMG at the Dugald River Zinc mine in Australia has led to the first global field trials and deployment of Orica’s Subtek™ 4D™ (hereafter referred to as 4D) Bulk Systems underground bulk emulsion blasting technology. This technology offers advantages over conventional bulk explosives by extending the range of energy and length of explosive column that can be charged in underground production. 4D gives blast designers energy options between Relative Bulk Strength (RBS) 50 - 150, delivered uniformly along the entire column in most blasthole conditions along with the ability to instantaneously modify the energy within an individual blasthole. During Phases 1 – 3 of the project from October 2022 to January 2023, over 57 tonnes of the 4D Underground emulsion were loaded in 17 stopes. The primary objectives of this phase were to reduce hanging wall dilution and improve stope recovery. While drilling and other parameters remained unchanged, the energy selection was tailored for specific situations, guided by a revision to the site's drill and blast standard. The design used low energy (RBS 50 - 70) in holes adjacent to the hanging wall and high energy (RBS 130 - 150) where stope recovery had historically been challenging, such as at the toes of long downholes. Initial results of the project focused on five stopes selected for their similarity to those used for the baseline data set. Although the 4D data set was small, the post-blast scans indicated favourable results for recovery and dilution. This suggests that selecting and delivering bulk explosive with tailored energy levels can improve stope performance.

Jan 1, 2024

By Amanda Verno, Danilo Coppe, Andrea Reggiani, Adolfo Bacci

The methodological example that comes from the demolition of the Genoa grain silos, should not been considered as an auto-celebration of a difficult project successfully executed, but should serve as an example of a new generation of demolitions where different technologies, often in competition, come together to obtain the optimal solution of a problem. Dynamite, diamond wire and hydraulic excavators overcame the most impressive building in town, working in very little spaces and on a geotechnically difficult site; moreover, a study on the dynamics and the effects of the impact of the structure, an analysis of the presence of potentially explosive dusts and an extensive vibrometric monitoring supported the design and the development of the operations.

Jan 1, 2005

By María Rocha, Benjamín Cebrián, Roberto Laredo

"Ring blasting designs have to achieve different goals in order to become efficient whether is done in up hole or downhole fashion. Ore recovery/dilution control, fragmentation and drift integrity all have to be taken into account when selecting parameters such as burden, spacing, linear explosive density and stemming. Blast energy simulation allows identifying contours of rock breakage and fragmentation, thuschoosing a combination of spacing at the end of holes and appropriate burden. Also, simulations are keyto concentrate energy levels on the mid part of the ring while making sure there is not too high of energy concentration around the drift, which integrity is needed for a safe ore mucking."

Jan 1, 2017

By Tristan Worsey

This work was performed during the summer of 2008 during the junior year of a BS in Mining Engineering. It was observed that the mine was having a problem with back break during the blasting of development drifts. The unwanted back break was causing the mine extra costs in ventilation, ore dilution, ground support, back fill, explosives and man-hours. The blasting practices were observed for four weeks and the problems and their solutions were defined. In this paper the reasons and causes of the problem are explained with the proposed solutions to eliminate back break.

Jan 1, 2010

By Dale Preece, Mike Stern, Steve Piercey, Ayman Tawadrous, GC Zhao

The McArthur River uranium mine in Saskatchewan, Canada is the world’s largest high-grade uranium mine. It has employed a freeze-wall system consisting of multiple freeze pipes to control the large quantities of water encountered during mining.

Jan 1, 2011

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan

In the bench blasting, the realisation of an economic, and safe blasting is only possible with a reliable blasting design on condition that considering all sequential activities such as drillingblasting, excavation-loading, haulage, crushing (especially primer crushing). Here what we mean with a good, and reliable design is that ensures an almost displaced, adequately swelled muckpile with desired fragmentation degree for the loaders effectivity, and succesive usage. Meanwhile it must also has no environmental problems such as ground vibration, air blast, and rock flyings, or at least these matters have to be minimised. Two main parameters which have generally being questioned to achieve a safe and economic design on any rock conditions, are specific charge, and burden. In the condition of determining these elements, the other blasting parameters could be calculated according to them, and the blasting design could be completed. Within the scope of this study, it was aimed to determine the optimal blasting conditions of gypsum which is major rock unit of overburden at Sivas Celestine open pit mine. First of all, the engineering (mass, and material) and digging difficulty classifications of gypsum were done according to the current classification systems by using the results of field and laboratory studies. Then the blasting system which was being used on all rock units, was considered, and the necessary data were obtained. After previewing the site properties, predesigns were done, and applied by adopting Langefors design model. The necessary adjustments were done before, during, and after the shots, and the applications were observed. In order to determine, and record the data from each shots properly, a practical form was developed, and all data were transfered to these forms which give information about the blasting results such as muckpile displacement, and height, average particle size, back break, and rock fly existence, number of boulders etc. The blasting parameters such as burden, hole diameter, hole inclination, the amount and position of primers, bench height, delay sequence, and blasting geometry were considered for the iteration of each shots. During the applications, ANFO, gelatine dynamite, and electric delay detonators were used as explosives.

Jan 1, 2004

By Dwayne Tannant, Jeffrey Loeb

Blasting techniques and protective measures exist that can mitigate risks associated with flyrock and the nuisance of vibration, and overpressure. However, these are often misused or not used because there are no prescriptive regulatory requirements and typically urban blasting guidelines do not exist. The relationship between the increasingly negative publicity that the urban blasting industry receives and the existing state of regulatory control on blasting in urban environments is presented.

Jan 1, 2012

By Roberto Folchi, Hans Wallin, Mara Battocchio

An understanding of explosives science and technology, and the competence to harness it is central to maintaining Explosives capability, national security, and in sustaining a competitive industry. A consequence of eroding this competence is the increased likelihood of explosives accidents. These are often catastrophic as demonstrated by accidents in Nigeria, Russia, Toulouse and Enschede. In addition to the serious loss of life there was the very significant damage to houses, domestic and industrial infrastructure and to the environment at a cost of many millions of Euros.

Jan 1, 2013

By Timothy Smith, Matthew Ryan, Dr. Anthony Konya

Hybrid specifications are a relatively new style of specifications specifically for the drilling and blasting industry that has seen widespread use over the last decade with the U.S. Army Corp of Engineers. This paper analyzed how this methodology was applied to develop this specification for the Soo Lock Deepening Project.

Feb 1, 2020

By John Petty, John Loviza

Single sentence describing content-- "The best ally an Explosives Engineer can have in a court of law is a regulations enforcer stating all codes and standards were met on a jobsite".

Jan 1, 1996

By Dean E. Albon

The author gives a brief resume of his observations of drilling and blasting supervision in surface coal mines during the past thirty years and recommendations for upgrading this supervision to the category of a professional.

Jan 1, 1979

By Gregory B. Poole

Data collected with 16K sampling at a variety of blasting sites (construction, quarry, trench, mine) and monitoring locations was analyzed to effectively show the 16 different 1K readings all based on the microsecond that the unit went into monitoring.

Feb 1, 2020

By Paulo C. Fernández A, Sergio Matamala V, Claudio C. Gajardo, Christian A. Rees P

In fragmentation processes in open-pit mining, it has been observed that there are many opportunities for improvement if greater control of ore displacement in blasting is achieved, reducing the percentage of mixing between ore and waste material (dilution) through the integration of new technologies that allow its quantification and optimization of extraction polygons. This work investigates the relevance of the initiation sequence and direction of displacement in blasting in relation to ore dilution and the potential benefits of process optimization. A three-dimensional modeling tool was used to evaluate movement control optimizing the extraction zone based on the maximization of ore recovery. The study was made by iterating different scenarios, by varying only the initiation sequence and inter-hole delays. To validate the displacement simulation, a total of 10 blasts were carried out for calibration, obtaining a level of agreement between the simulation surface and the actual topographic survey of 80% or higher. The analysis included horizontal and vertical displacement, quantification of swell and dilution within extraction polygons for different scenarios, and informed decision-making based on ore control. The results clearly indicate that by modifying the blast initiation sequence, greater control over dilution in ore/waste transition areas is achieved, thus optimizing the recovery of the planned material and maximizing the ore grade. The use of this type of simulation tools allows for the generation of extraction strategies based on the value of the polygon, unnecessary displacements in the free face, optimal loading fronts, etc., maximizing the recovery of ore and stockpile material, complying with the planned tonnage and ore grade for each extraction polygon, delivering added value to the chain and emphasizing the importance of adding new technologies to the mining industry that allow for the optimization of processes to maximize profits.

Jan 26, 2026

By Shadrack Nuamah, Erik Westman, Bright Afum, Jesse Addy

Rock fragmentation is the most critical aspect of hard rock production blasting due to its significant impact on drilling and blasting costs and the economics of subsequent loading, hauling, and crushing operations. This study analyzes current cost trends in the drill and blast operations of an anonymous open pit gold mine and proposes cost-effective drill and blast geometric parameters. The investigation focused on one operational pit with provided design parameters for two shots, shot 1 and shot 2. Existing blast parameters and two additional proposed sets of geometric parameters were evaluated using the Kuz-Ram and Chung and Katsabanis fragmentation models to estimate mean fragment sizes. The results indicated that the proposed blast parameters produced estimated mean fragment sizes within the mine’s desired range (not exceeding 45 cm). Additionally, the explosive energy was utilized efficiently per in-situ material blasted. The proposed parameters increased the estimated total volume of in-situ material fragmented by approximately 14% for both Shot 1 and Shot 2 compared to the current parameters. Furthermore, adopting the proposed blast parameters could lead to significant cost savings. The evaluated total drill and blast cost savings were approximately 11% for Shot 1 and 12% for Shot 2. These savings stem from the increased efficiency and effectiveness of the blast operations, highlighting the potential for substantial economic benefits. This study demonstrates that optimizing blast geometric parameters will allow open-pit mines to achieve desired fragmentation, utilize explosive energy more effectively, and realize considerable cost savings in drill and blast operations.

Jan 21, 2025

By Michael A. Peltier, Dennis V. D'Andreal, Larry R. Fletcher

Accident data obtained from the Mine Safety and Health Administration (MSHA) were analyzed by the Bureau of Mines to determine the most frequent causes of blasting accidents in U.S. mining and to examine trends in blasting accidents. This accident analysis is an update of a similar blasting accident study conducted by the Bureau and published in 1983. The analysis shows that there has been a recent reduction in mine blasting accidents: The annual average number of nonfatal injuries has decreased from 107 for 1978-81 to 46 for 1982-85. The annual average number of fatal injuries was reduced from 11.3 to 5.0 during that time.

Jan 1, 1987

By R L. Keller

Hong Kong has some of the most restrictive practices regarding blasting than any place in the world. Regulations regarding vibration limitations are 1 in/sec for structures and 0.5 in/sec (or even less) for most utilities; with no recognition of frequency response or adjustment. The Hong Kong Geotechnical Engineering Office has one of the most conservative approaches and protective guidelines for pre-blast assessment of slopes subjected to blast vibration (SEE paper '96). The protective measures to control flyrock generally required by the Mines Division are additionally very stringent. It is not uncommon for the costs associated with protective measures or methods which must be employed to exceed the cost of the drilling and blasting itself - or to waiver blasting application unfeasible altogether. From these restrictions it can easily be imagined how blasting in this urban environment would be most challenging.

Jan 1, 1997

By Michael Laing

"Geology plays a critical role in many aspects of blasting, from fragmentation to wall control. One often overlooked component of blasting concerns blast results due to the effect of geologic features. The direction of blasting, with respect to strike and dip, can produce varied results, depending on thescenario. Working with geological features, as opposed to against them or without regard to them, can therefore dramatically improve blasting results. This paper focuses on the role of “geologic features”, which include joint-sets, natural fractures, and bedding planes (all of which are commonly referred to as “seams”) for the purposes of this paper. The goal of this paper is to promote understanding and mitigation techniques for various scenarios in which there are identifiable geologic features. Depending on the nature of these features (strike and dip specifically), blast design and pit advancement/development can be carefully considered to use make the best use of these features and optimize blast results."

Jan 1, 2016

By T. Bajpayee, G. Mowrey, D. Ingram, T. Rehak

Blasting operations are an essential element in the recovery of our Nation’s mineral resources. The mining industry uses billions of pounds of explosives annually. The majority of blasting occurs in surface mining .operations. Blasting results in the fragmentation and often the projection of rocks. Frequently, the rocks are thrown beyond the expected limits. Flyrock and failure to secure the blasting area dominate blasting-related accidents in mining, especially in surface mining.

Jan 1, 2001

By Isaac E. "Chip" Harris

A general understanding is given to how and where blast hole drills are used and what recent developments have taken place with small and large diameter drill hole machines. Indications are that new developments with high penetration rates and large diameter holes are not necessarily the answer to increased production in the field.

Jan 1, 1979

By Harry Verakis, Thomas Lobb

Blasting accident data over a 30-year period (1980-2010) are summarized and presented for all types of surface and underground mining operations in the USA. The historical record of injuries from blasting accidents in all types of mines continues to show a significant decline. The overall decline in mine blasting injuries in the U.S.A. has resulted from advancements in blasting technology, training and improvements in blasting products and blasting processes. Some of the technology advancements such as safer blasting agents and computerized bulk vehicle loading, electronic detonators and remote operated blasting systems, and computerized blast design have and continue to significantly contribute to improvements in the historical blasting safety record. Also, the progress of significantly improving the safety of mine blasting has resulted from the combined efforts of miners, mine companies and operators, miners, unions, explosive and blasting product manufacturers, associations such as the International Society of Explosives Engineers and the Institute of Makers of Explosives and various government agencies.

Jan 1, 2012