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By Thomas M. Keevin, Gregory L. Hempen

Natural resource agencies, under various regulatory authorities, are challenged with permitting underwater explosive use while at the same time protecting aquatic resources. Deciding on whether or not to allow use of explosives requires striking a balance between development and aquatic resource protection. A company's goal in underwater explosive use is to select methods that are both expedient and cost effective. Use of explosives is often the best alternative for engineering reasons or economic considerations. Over and above legal requirements, indiscriminate destruction of fish and other aquatic resources is not in a company's best interests because of concerns relating to public image, as well as the need to secure future contracts.

Jan 1, 1995

By Dale S. Preece

A new three dimensional (3D) mechanistic model of fragmentation, called the Fracture Density Model (FDM) is used to simulate full-scale bench blasts at the Bararp dimensional stone quarry in Sweden. The model uses several computational mechanics algorithms to simulate the effect of blasting in different rock types

Feb 1, 2020

By Raphael Trousselle, William Reisz

The blasting industry is now well into its second decade of commercial use of electronic detonators. As an increasing number of blasters are introduced to the technology, the benefits are becoming more widely monitored and accepted in many surface blasting operations. However, their use in underground applications is not yet as widely established. This is primarily due to the distinct cost dynamics and processes associated with underground lasting.

Jan 1, 2012

By Matt Brandon

This case study demonstrates how integrating drone and GPS surveying with 3D modeling software creates more effective blast designs that address specific geotechnical challenges while improving safety and blast performance. In this case study an 80ft (25m) highwall experienced recurring slip plane failures exacerbated by a previously mined 40ft (12m) bench that removed back support, creating an unstable triangular rock mass. Previous blasting along this wall displaced the upper 40ft (12m) of material, opening geological discontinuities and causing progressive slope failures that compromised crew safety and blast effectiveness. High-resolution drone photogrammetry, GPS surveying, and laser measurements were employed to precisely map slip planes, bedding planes, and fault structures within the bench geometry. These geological features were imported into 3D design software to develop a shot pattern that strategically utilizes natural rock discontinuities rather than working against them. GPS-guided hole placement ensured accurate field implementation, while marking geological features on the surface of the bench provided visual references for the blast crew. The final blast design positioned the last row of holes to break preferentially along an existing slip plane while avoiding intersecting the next slip plane behind the blast. Explosive loading and timing sequences were adjusted based on the hole location relative to the 3D geological model to optimize fragmentation while maintaining wall stability. The optimized design improved highwall stability significantly, by reducing the slip plane failure mechanism that had previously compromised operations. Measurable improvements included enhanced highwall stability, reduced back-break, improved blast performance, and reduced safety risks for equipment operators and blast crews. Two subsequent shots using identical methodology were able to remove the rest of this problem area, confirming the repeatability and effectiveness of this integrated approach. This methodology demonstrates practical integration of surveying technologies with geological understanding to solve complex blasting challenges. Accurate 3D modeling of geological features enables blast designers to work with natural rock structures rather than against them, resulting in safer, more effective blasting practices. This case study shows the value of understanding the precise locations of geological features for optimizing blast design and provides a replicable process for addressing geotechnical challenges in blasting operations.

Jan 26, 2026

By PHILIPP HARTLIEB, Peter Schimek, Thomas Seidl, Pablo Segarra, José A. Sanchidrián, Juan Navarro

This paper develops a new Blastability Index to assess hole-to-hole fragmentation in bench blasting based on a new Rock Factor exclusively obtained from drill-monitoring data, that can provide an automatic assessment of rock structure, strength, and waste/ore, the effective energy factor of the explosive and the delay time per blasthole.

Feb 1, 2020

By George W. MacDonald

ALFRED NOBEL was born at Stockholm on October 21st. 1833, and died on December 10th, 1896. Although Sobrero’s discovery of nitroglycerin dated back to 1847, this explosive was manufactured on a commercial scale for the first time in 1862, by Nobel at a factory which he erected at Heleneborg, near Stockholm. These works were entirely wrecked by an explosion in 1864. In 1865, he erected works, which are still in existence, at Winterviken, near Stockholm. In 1864 Nobel introduced modifications in the manufacture of nitroglycerin which were the subject of a patent (see footnote No. 1), and at the same time, claimed a process for the detonation of nitroglycerin. Nobel states that, up to that time, the method used for the manufacture of nitroglycerin consisted in pouring glycerin, drop by drop, into a mixture of sulphuric acid and nitric acid contained in a refrigerating mixture. In order that the nitroglycerin should not be decomposed, the temperature was not allowed to rise above 0° C.

Jan 1, 2012

By PHILIPP HARTLIEB, Peter Schimek, Thomas Seidl, Paulo Couceiro, Pablo Segarra, José A. Sanchidrián, Juan Navarro

This paper describes a new methodology to assess rock mass-quality to guide blasting in open pit operations. A developed Structural Block Model and Strength-Grade factor have been combined in a Rock Factor, that, exclusively obtained from drilling data, can provide an automatic assessment of rock structure, strength, and waste/ore identification.

Feb 1, 2020

By W B. Gregg

"A review, update, and expansion of Thiokol’s presentation at BAl’s Fiih High Tech Seminar titled ‘ADetonator - An Era of Precision in All-Electronic Detonators” is provided herein (and should be considered as a supplement to that publication). Thiokol is currently in the development and field evaluation phase of activities for our ACCUBLASTTM all-electronic detonator. The ACCUBLASTTM detonator uses a semiconductor bridge (an electronic match) in place of a conventional hot wire to initiate a safer, less sensitive material, titanium subhydride potassium perchlorate. The device is programmable to provide blast delays in one millisecond increments ranging from 1 to 500 milliseconds. The ACCUBLASTTM detonator combines an all-electronic programmable timer coupled with a semiconductor bridge to ensure detonation timing accuracy with +I00 microsecond precision. Initial development and field testing have been completed. These tests have verified ACCUBLASTTM detonators’ precision."

Jan 1, 1995

By Alvin D. Christmas

The missing link is a connector between the congested downtown area of Knoxville, Tennessee adjacent to the former World's Fair site, the I_40 I_75, and Western Avenue traffic arteries. This connecter was designed to accommodate the 37,470 motorists who presently travel through these highly congested narrow paths to be replaced by the 21.8 million dollar Henely Street Connecter. All construction and blasting was to take place while existing traffic was re_routed so as to allow access between the downtown area and the vital interstate corridor. To avoid major traffic problems, the project was to be accomplished in three phases: (1) the Western Avenue viaduct demolition; (2) two new viaducts to be constructed; (3) the open box cut at Henely Street next to the L & N Depot. Due to the past attempts by the Fort Sanders Community Home Owners group and the Historical Society to stop the Henely Street Connector, this project involved a very comprehensive blasting damage control program with special provisions of .5 inches per second measured at the foundation of the closest structure.

Jan 1, 1995

By Sunil Vytla, Akash Adhikari, Purushotham Tukkaraja

Blasting operations produces gases and fumes that may be toxic or non-toxic in nature. A detonation of commercial explosives such as ANFO, emulsion, and dynamite would ideally produce only nontoxic products such as steam (H2O), carbon dioxide (CO2) and nitrogen (N2). However, in the real world, the detonation of explosives produces toxic products such as nitrogen dioxide (NO2), nitric oxide (NO) and carbon monoxide (CO). The focus of this study is the blast fumes entrapped in the muckpile. Fume clearance and workplace re-entry time studies performed in the past have overlooked the toxic gases entrapped in the muckpile. Studies show that as much as 60% to 70% of the fumes or gases produced during blasting underground can remain entrapped in the adjacent rock mass or in the muckpile. The toxic fumes trapped inside the muckpile are slowly released and could be fully uncovered during the mucking process. Exposure to these gases or fumes is hazardous to mine workers. In this study, author have analyzed the nature of fume flow, i.e. accurately predicting where and how the fumes flow after an underground development/tunnel blast. This will help in determining i) precise re-entry times for the workers ii) rate and direction of the fume flow. Computational Fluid Dynamics (CFD), a mathematical simulation technique that predicts fluid dynamics phenomena is used for this purpose. CFD is preferred over physical models because it is inexpensive, once the accuracy is established, a wide range of scenarios can be simulated quickly, and the toxic gas flow patterns through underground openings can be analyzed efficiently. For this study, CFD is performed using SC/Tetra software owned by MSC software company.

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 Thomas E. Ricketts

Occidental Oil Shale, Inc. constructed two commercial-sized modified in situ (MIS) retorts, Retorts 7 and 8, at its Logan Wash Oil Shale Mine in February and April 1981, respectively. One of the primary objectives of this two-retort program was to examine large-scale blasting reproducibility for commercial-sized retorts. The blast design used 545 blastholes and 550,000 pounds of explosive in ANFO equivalent per retort. Each retort was blasted using millisecond delay blasting caps tied into a single round. The blasts resulted in rubble beds very close to one another and to predicted results obtained using newly developed limited void blasting technology. The heights of the remaining void rooms over the beds after blasting were within 0.3 feet of one another. This excellent reproducibility is brought into true perspective when compared to the scale of the rubble beds which were 230 feet high with volumes of over six million cubic feet each.

Jan 1, 1984

By Matthew Hirsch, Jason Connot, Nathan Rouse, Srivatsan Jayaraman, Akash Adhikari, Brent Meins, Purushotham Tukkaraja

The Deep Underground Neutrino Experiment (DUNE) is a world-class particle physics research project currently being constructed 4,850 ft, 1,478 m underground at the Sanford Underground Research Facility (SURF), former site of the historic Homestake Gold Mine in Lead, SD. Construction for the project involves drill and blast excavation of 800,000 tons of rock to house neutrino detecting cryostats adjacent to on-going particle research and sensitive lab areas. To protect nearby labs during the planned 4 years of blasting operations, project specs required installation of six steel, heavily reinforced blast doors designed to withstand 20 psi blast loads. This research aimed to quantify the pressure reduction across the blast doors and more accurately model underground blast wave propagation. 827 blasts to date have been monitored at eight locations on the 4850 level of SURF with some locations behind blast doors and some in front. Additionally, pressure measurements directly in front of and behind one blast door were taken during 94 blasts.

Feb 6, 2023

By Duncan Chalmers, Rob Nowell, Miguel Araos

Australian underground mines produce in excess of 60 mtpa of coal. Most of these use the longwall method, and they require the use permitted explosives (which are called “permissible” in other countries) for challenges that appear during the day-to-day activities. To obtain the approval for these explosives, they should pass Testing Memorandum #2 (TM-2), which sets out the test required for each category of permitted explosive. These categories are P1, P3, and P5. With P5 being unrestricted use and P3 and P1 have conditional use in underground mines. The TM-2 test was originally set up for NG-based permitted products around 1900. With the closing of NG plants around the world, ammonium nitrate explosives were the natural replacement, and therefore these explosives need to pass the TM2. Australia does have a P1-emulsion based explosive available. For high-risk scenarios (like blasting coal), no P5 explosives are available. The lack of P5 explosives has been prolonged for more than 25 years, since the phasing out of nitroglycerine-based permitted explosive products around the world. The main problem has been that when emulsion based permitted products are tested in the deflagration cannon, the results obtained were not considered in the TM2 criteria and therefore the tests were invalid. A research work on permitted explosives began in 2005 funded by the Australian Coal Association Research Program (ACARP). The aim of the project was to address the lack of P5-type permitted explosive (and, potentially develop them further, i.e., develop safer explosives) and understand the behaviour of emulsion explosive and the results they presented in the tests. Both bureaucratic and technical barriers appeared along the way. On the bureaucracy side, the facility was shut down, reopened, and shut down again. In view of these difficulties, assistance was sought overseas. On the technical side, from the very start the results of the tests when using emulsion-based permitted explosives were not established in the criteria, ignitions occurred for trial samples that were expected to be P5-type, etc. The aim of this document is to present the painful journey in the Australian industry to have a P5-type emulsion-based permitted explosive, for use in UG coal. Also, the technical learning acquired about emulsion explosives and the ignition path of mixtures methane / air will be shown.

Jan 21, 2025

By Lawrence Mirabelli, AngloGold Ashanti, Greg Gibson

Cripple Creek & Victor Gold Mining Company (CC&V) operates the largest surface gold mine operation in Colorado and is located west of Colorado Springs in Teller County between the towns of Cripple Creek and Victor. Gold was first discovered in the Cripple Creek mining district in the 1890s. CC&V has been conducting gold mining and precious metal extraction operations in the Cripple Creek Mining District since 1976. Current reserves are only amiable to surface mining since previous underground mining has depleted near surface ore rich veins.

Jan 1, 2014

By Kia Riihioja, Mike Higgins

A major difference between electronic and pyrotechnic detonators is that, in almost all but the simplest of blast layouts, computer software is required to plan a blast using electronic detonators. While it may be possible to program delay times without software, using only the manufacturer’s control hardware, the full potential of electronic detonators can only be realized through software. Until recently, the only software available has been provided by the suppliers of the electronic detonators. These usually have just enough features to create a hole layout and to assign times to the detonators in the holes. The software is also able to communicate only with the manufacturer’s detonators. This means that the client may be compelled to change several parts of the blasting process when a different delay system is adopted, from design through to implementation and reporting, even though these may be sub-optimal at the client’s mine. While many authors have demonstrated improvements in blasting outcomes using electronic detonators, very few have discussed how the delay times were calculated. Where the calculations are discussed, it is also obvious that the delay times must be monitored and re-evaluated as conditions in the mine change. For example, the principles of superposition and scaled distance, burden relief and energy cooperation between holes should be checked constantly for different locations within the mine, changes in rock properties, or even for differences between design and actual hole positions. The most common methods in blast design software to calculate delay times are inter-hole interval, relief contour and direct editing. Although they are simple in concept, they can result in fundamental errors if they are not applied correctly. The software for electronic blast designs should be capable of not just a timing calculation, but also of showing, to some degree, the impact and interaction of the calculated times.

Jan 1, 2004

By Gregory Hempen, Thomas Keevin, Russell Wilcox, William Wild

The Department of Defense Strategic Environmental Research & Development Program (SERDP) awarded funding for evaluation of procedures to mitigate peak pressures and energy flux density in the water column from ordnance being detonated on the ocean floor. The research purpose was to conduct scaled testing to resolve whether a theoretically-viable covering technology was operationally effective in reducing blast effects and the impacts of shrapnel. An additional objective was testing effectiveness of this method for hard-bottom units (rock or coral) and (unconsolidated) sediment substrate.

Jan 1, 2011

By Baohua Guo, Xuelin Yang, Tingkan Lu, Hailin Sun

The work presented in this paper mainly involves two parts. Firstly, the fundamental characteristics of the high pressure carbon dioxide gas fracturing technique (CO2 technique), including, a proposed method of TNT equivalence calculation, which is used to calculate the TNT equivalence of discharge of CO2 technique, and the comparison of the explosion volume generated by dynamite and expansion volume of liquid carbon dioxide is conducted to show the differences of fragmentation capacity between the two of them. Secondly, the coal seam fragmentation mechanisms of CO2 technique are proposed, including, 1) Gas jet cutting and penetration by shaped charge, 2) Gas volume expansion by changing phases of carbon dioxide, 3) Coal seam softening by destress blasting and 4) Coal seam fragmentation by discharge vibration, associating with the mechanisms, the equations for calculating fragmentation radius are developed and verified.

Jan 1, 2017

By John Atkinson, Steve Repola

This paper will describe two blasting plans that have been developed for American Aggregates' Marble Cliff Quarry located near Columbus, Ohio. Two different limestone formations are mined on different levels of the quarry. Each formation requires a different blasting plan which address vibration considerations, crusher productivity, drilling and blasting costs and adjacent neighborhood concerns. Controlled blasting is critical to continued mining operations in this Midwest urban setting.

Jan 1, 1993

By Jason Baird, Joshua Hoffman, Phillip Mulligan

The purpose of this report is to address the method of reducing the overall explosive weight of Explosively Formed Projectiles (EFPs) while still achieving satisfactory performance. This reduction is crucial in order to comply with outdoor explosives testing standards for Missouri University of Science and Technology’s (Missouri S&T’s) Experimental Mine. Initial EFP design testing exceeded given limitations, making reliable data difficult to ascertain. EFPs must be tested outdoors to allow for specific information recordings which aid in defending against them.

Jan 1, 2010