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By Darío Innamorati, Jorge Oliva

Cerro Vanguardia is a known gold and silver deposit located in the province of Santa Cruz, Argentina. The mine has been in operation since 1998 and is thought to be one of the most important mines in Patagonia. More than 102 epithermal quartz veins have been identified in the area, with variable lengths, thicknesses, orientations and dips that constitute what is possibly one of the most extensive outcropping vein systems on earth. Veins are vertical and have variable depth. For this reason, the deposit is currently mined with a variety of extraction methods. This operation is made up of more than 60 open pits and 20 underground access ramps to exploit the deepest high grade narrow veins. This study is focused on the combination of underground exploitation with open pit blasting. That is, those production stopes in the upper levels of underground mines and their interaction with the damage levels in the final slope of open pit mines, as well as in the study of the impact of the generation of vibrations from the blasting of open pit mines and their influence on underground mines. Considering the current stage of the mine, after 20 years of operation, Cerro Vanguardia faces the need to mine deeper deposits in the face of increasing costs and declining grades. For this reason, it is essential to study the interaction of these exploitations. From a personnel safety point of view, this interaction must be well coordinated so as not to affect people and equipment. Likewise, the generation of vibrations due to blasting must be studied, which would produce new cracks, potentially generating overbreak and dilution. The main objective of this study is to determine the possible causes and influences of the blasting interaction in open pit and underground mines, seeking an optimization of the blasting process and a safety standard for personnel and equipment. To achieve these goals, this study includes a vibration monitoring plan to analyze the charge performance and determine rock constants. With the use of specialized software, damage modelling and simulations are used to determine values of damage in order to reduce overbreak. In addition, this plan contemplates the estimation of flyrock in blasting where underground work is connected to the surface, determining safety distances when carrying out a blast.

Jan 21, 2025

By J J. F Smith

The application of pneumatically loaded ANFO for underground mining has continued to increase year by year since the technique was first developed and introduced underground during the early 1960's. Improvements in the manufacturing process for explosives grade prills, the design and construction of more efficient AN prill-fuel oil blending equipment, and the introduction of more durable and reliable pneumatic loaders have promoted the wide application of the relatively low cost blasting agent, ANFO.

Jan 1, 1982

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 William Yutmeyer, Meredith Hardwick

Since 1996 there have been at least two teams formed within the U.S. Government to develop a consistent set of risk-based standards to be used to govern safety. The first of these was the Risk and Lethality Commonality Team which developed risk criteria associated with protecting personnel during launches at the national test ranges. The second team titled the Risk-Based Explosives Safety Criteria Team (RBESCT) is the subject of this paper.

Jan 1, 2007

By James L. Wilcox, Douglass P. Bacon

As the U.S. Environmental Protection Agency (USEPA) and state regulators increase the stringency and enforcement of regulations concerning emissions produced by open-air detonation of energetic materials, research must provide the means of obtaining emissions data. The BangBox emissions testing program established the technical foundations for emissions characterization which have been accepted by the USEPA and other regulatory agencies; the technical issues remaining are nettlesome and require new approaches in test procedures.

Jan 1, 1996

By William C. Lane

The Pacific Northwest has an abundance of seamy, coarse granite and basalt rock. It is used primarily for road construction. Small quarries are opened nearest the road work to cut the cost of hauling. The crushers are portable. Small diameter holes 2 1/2" to 3 1/2" are placed close together to insure proper fragmentation. It is not unusual to load and shoot 100 to 700 holes 40' deep.

Jan 1, 1986

By Al Romphf

Managing blasting-induced air overpressure levels is a key compliance requirement for most blasting operations. Regression analysis, plotting overpressure amplitude vs cube root scaled distance, will often present a level of scatter which should be considered unacceptable. Relying solely on regression-based predictions can lead to overly conservative restrictions that may negatively impact other key performance indicators. Improved methods are needed for accurate overpressure prediction. The Heelan-Blair wavelet has been shown to closely resemble the overpressure waveshape produced when a single charge is fired under typical confinement conditions. The amplitude of a single-hole overpressure wave is influenced by factors such as proximity to the receiver, charge mass, orientation, and confinement both at the collar and face. Additional factors, including timing sequence, barrier effects, wind direction and velocity, must also be considered. The linear superposition method, commonly applied for ground vibration prediction, can be adapted for air overpressure modelling. In blast design software, this approach can consider all relevant parameters and environmental interactions. Given the uniform nature of air compared to rock, linear superposition using realistic elemental wavelets may replace the need to fire a signature hole. Data from 38 single-hole blasts conducted at quarries and mines throughout North America were used to develop and calibrate a linear superposition model. This model reasonably reproduces air overpressure results from full-scale production blasts, offering a practical approach to overpressure compliance and prediction.

Jan 26, 2026

By Enver Alan

In this study of applied explosives engineering the blasting applications are evaluated, which were carried out for research and development purposes at Yenisahra Station tunnels in Kartal Formation which was built with the aim of solving İstanbul's transportation problem within the framework of the Kadıköy-Kartal Metro Project. Twenty-four shots were made by using explosives in 60 blastholes that were drilled in the tunnel faces, which were located between and outside of two different faults. S

Feb 1, 2020

By Paul Worsey, Terry Nixon

The development and testing of a simple mechanical stemming aid (Patents pending) resulting from a Joint venture by Incubator Technologies Inc. and the University of Missouri-Rolla and funded by the U.S. Department of Energy is described. The aid comprises a solid unit placed in the stemming above the explosive column and is designed to improve blasting efficiency and reduce drilling and blasting costs. It works with back filled drill cuttings or any other suitable stemming material.

Jan 1, 1988

By Jon Andrews

Purpose: To show how in managing risk in avalanche control blasting has changed throughout the years, and try to define the term “Acceptable Risk”. History: The history and the way we manage risk in avalanche control blasting to the avalanche control crews and public has change over the years dramatically. From the mid 1800s to about 1920 was the Risk vs. Rewards era, the Industrial Revolution. Now it is a Risk vs. Liability, the age of Liability.

Jan 1, 2009

By Paul Worsey, Larry Kenchel, David Randall, Mark Schmidt

The University of Missouri-Rolla (UMR) has historically maintained a manual, paper inventory of explosives stored and used at the university. Although this system was accurate for inventory control and reporting criteria, it was labor intense and delays in record keeping were predominant. A directive from the university’s administration mandated the development of a precise real time system “on-line” to maintain and control the explosives inventory in line with the universities new chemical tracking policies.

Jan 1, 2001

By Richard D. Love

Competition in the aggregate industry of the 90's will be an over increasing really. With this in mind a quarry manager should always be comparing new and innovative concepts to increase productivity and reduce operating costs. In this paper, the author will present a comprehensive history of a drilling and blasting program that achieves these results. By employing proven methods and implementing new concepts, this program was proven to be a success over a ten year period.

Jan 1, 1991

By Ann Barron

Even though you think your company’s safety program is the best it can be, equipment, processes, supplies, surroundings and people do not always behave or react as expected. Consequently, needless accidents occur each year at quarries, construction sites, surface mines, and other locations where explosives are used. While blasting accidents account for only a small portion of the total accidents reported, the severity rate for blasting accidents is higher than for any other accident category.

Jan 1, 2007

By David E. Siskind

In the period 1989 to 1994, the U.S. Bureau of Mines assisted the Office of Surface Mining, Reclamation and Enforcement (OSM) in studying a high-complaint situation near an active surface coal mine. As part of a review for its project report, the Bureau had to address issues on the adequacy of the safe blasting criteria and analysis procedures in its 1980 report RI 8507, Structure Response and Damage Produced by Ground Vibration From Surface Mine Blasting.

Jan 1, 1996

By R C. Berglund

Since the Republic Mine began production in the mid 1950's, drilling and blasting practices have continually changed. In recent years, progress has been achieved through the development of more precise blast engineering methods, in greatly increasing the use of non-water resistant ammonium nitrate explosives, and in changing to a non-electric in-hole delay initiation system. Also, recent experience indicates that ammonium nitrate fueled with nitropropane and methanol is a viable substitute for aluminized AN-FO.

Jan 1, 1980

By C A. "Hawk" Hanger

"The paper that will be presented is an in-depth study of sequential blasting using standardnon-electric shock tube down hole timing along with surface M.S. connector timing.Included also will be a discussion on the advantages in fragmentation, digability, oredilution' and ground vibration versus the common practice of row by row blasting. Alongwith the written presentation, several visual illustrations will be included. The visuals willrefine the actual direction and predicted movement of the shot involved."

Jan 1, 1993

By Gordon C. Petersen, Gary A. Almeraris

This paper describes the controlled blasting techniques required to mine a rock tunnel section of a main interceptor located in the Boston Metropolitan area. The 3m (10 ft) x 2.8m (9.25 ft) horseshoe shaped tunnel was driven 490m (1600 ft) by conventional drill and blast methods. The geology varied round by round and consisted of five highly faulted and jointed igneous rock types. The tunnel intersected numerous slickenslides and open mud seams which hampered both drilling and loading operations. Smooth blasting wee critical in order to keep overbreak tc a minimum in this extremely hard but blocky ground.

Jan 1, 1991

By Joe Strobbe, Kevin Joe

The U.S. Bureau of Reclamation awarded PCL Civil Constructors the project to build a new visitor's center and parking lot structure at the Hoover Dam. The excavations for these structures present many blast design challenges. The visitor center, a 30 foot deep excavation was blasted in the Nevada side of the canyon wall, 600 feet above the existing power plant. This excavation also included a through-cut underneath the existing road that carries the traffic over the Dam between Nevada and Arizona.

Jan 1, 1993

By Jerome S. Brower

Quadrex-L is a two component liquid explosive which was developed by J. S. Brower & Associates, Inc. to facilitate handling and shipping, and use in unique applications, while emphasizing safety. It may be advantageously used for all explosive applications. Quadrex-L can be introduced into a preinstalled container configuration and may be easily drained or flushed from these containers when necessary to do so. This characteristic can be effectively utilized to reduce the hazard period during assembly or disassembly operations.

Jan 1, 1975

By Franklin J. A, Tam C. Palangio, N H. Maerz

WipFrag systems I, II and III have become the world standard in photoanalysis systems to measure particle sizes. Mines, quarries and excavating contractors can now easily measure blast results and track the progress of optimization efforts. This technology was developed and evolved ~to allow automatic measurements of the size distribution of particles on moving conveyors, in truck boxesand on crusher feeds. Production machinery can now be controlled by photoanalysis results and multiple cameras allow various locations to be monitored by a single system. Blast designs can, be monitored on a shot by shot basis. Changes in delay times, explosives, patterns and hole sizes can be quickly evaluated. Along with this measurement capability has come a heightened awareness of the importance of “optimum size” and uniformity of particles for lowest cost production and material handling efficiency. In the past, savings in the “drill / blast” cycle of the operation were sometimes overshadowed by downstream production costs related to fragmentation. Now total production costs can be compared with fragmentation sizes, which will immediately show the trend towards optimum size for economical production. No cost reduction program can be complete without this critical information.

Jan 1, 1998