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By G J. Kulbieda

The Empire Mine initiated production in 1963. Since then the unit operations of drilling and blasting have evolved continually in order to meet the increased mining requirements demanded by plant expansions in 1968, 1973 and 1980. Additionally, advance mine planning has become an integral part of proper pit development and is necessary to insure uniform blending of the distinct ore horizons contained within the mine area. Blasting practices have been modified to facilitate the autogenous grinding system utilized at Empire and pioneered in the Iron Ore Industry. Technical innovations in the explosives industry, as well as, progress regarding on site blast engineering methods have substantially increased the use of ammonium nitrate explosives and helped to establish efficient charging procedures. In addition, the recent introduction and use of ammonium nitrate fueled with nitropropane and methanol indicates that it is a viable substitute for aluminized ANFO.

Jan 1, 1981

By Roy McKinstry, Mark Rantapaa, Thomas Bolles

In March of 2001 Barrick Goldstrike Mines, Inc. began evaluating the potential benefits of electronic detonators at the Betze Post open pit gold mine. The original evaluation focused on increased fragmentation, and excavator productivity. During the original evaluation there was an attempt to quantify mill throughput. Early tests indicated that there would be a benefit to mill throughput, however management was hesitant to take on the added cost of electronic detonators based on the initial evaluation. In early 2002 a decrease in mill throughput was being forecast as a result of harder ore being encountered. As a result of the initial electronic detonator evaluation a team of individuals from the Open Pit and Process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative. This initiative was targeted at improving mill throughput as the harder ores were encountered. Batch tests were conducted to determine if adjustments to drilling and blasting in the open pit could increase mill throughput and justify a 50% increase in drilling and blasting costs for the harder ore material.

Jan 1, 2004

By James Ludwiczak

This paper consists of the conduct of a forensic criminal investigation of the components, construction, use, and functioning of two suicide bombs. As the title states, the task was to form professional opinions as to whether the bombs would work, would cause property damage, and would injure or kill. The bombs were created and installed by a defendant in a Federal death penalty case where the defendant’s daughter was killed in a shootout with the West Virginia State Police. The two black powder bombs were placed under the front seats of the defendant’s automobile and were designed to function by the use of a toggle switch connected to the automobile’s cigarette lighter. The forensic work first consisted of an inspection of the remains of the wiring system and bombs at the Bureau of Alcohol, Tobacco, and Firearms Laboratory, in Ammendale, MD. This was necessary to determine and detail the wire diameter and lengths, the lengths and size of the wire used, the type of toggle switch used, the type of containers, the type of rocket motors used to initiate the black powder, the manufacturer and amount of black powder used in each bomb, and the type, wraps, and amount of duct tape used for the construction of each bomb. Using this data, tests were conducted by duplicating the wiring system and the two bombs to insure that the system functioned properly. Each bomb was duplicated and initiated to observe the violence produced when initiated in the open air. Duplicate bombs were placed under the seats of a similar type of automobile and initiated. The purposes of the tests were to duplicate the bombs, to observe the violence of the initiation, and to observe the damages to the automobile produced by the initiation.

Jan 1, 2007

By H Russell

An account of an experimental blast at the Sullivan Mine involving a small pillar drilled with 4 1/2" diameter up-holes, and loaded with emulsion explosives from a truck-mounted tank/pump unit.

Jan 1, 1984

By Richard L. Ash, Calvin J. Konya

Proper selection of the spacing distance between blastholes is fundamental to successful blasting. Its value directly affects the profitability of an operation. It also exercises control over adverse effects such as airblast, flyrock, generation of ground vibrations, and overbreak. One of the more significant factors influencing the spacing's specific value is the initiation firing time intervals used between blastholes. Examples are described to illustrate some of the problems that result when spacing and timing are not compatible.

Jan 1, 1979

By Christoper J. Hunter, Tony Mansel, Carl Kolada

With a current trend toward Bulk Mining methods utilizing both large diameter uphole and downhole drilling, corresponding loading equipment and technology is required to safely and efficiently load these blastholes. Such is the case at Inco Limited Thompson Mine.

Jan 1, 1990

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 J R. "Dick" Daniel

In the fall of 1988, The Cannon mine decided to investigate a central blasting system based on conventional electric blasting detonators being used to initiate rounds primed with Nonel detonators. The advantages of this hybrid detonator system were viewed as being safety and cost effectiveness. A study was done reviewing the safety aspects of utilizing a permanent blasting line installed throughout the main haulage drifts to a central blasting station located at the mine portal. The study addressed the following potential safety hazards: radio frequency induced current, stray current from both electrical utilities and transmission lines, galvanic and electrostatic sources of extraneous current.

Jan 1, 1989

By Kamal Wadhwa

Ever since the introduction of Liquid oxygen explosives in India in 1927, these explosives are being extensively used in the various mining industries such as coal, ironore, limestone, bauxite, magnesite etc. The earlier LOX compositions were based on cellulosic material of Weberlox series of French origin. They contained the basic ingredients of saw dust with an admixture of cork dust, some hydrocarbons and some metallic powders. However, there were some inherent defects in the soaking characteristics of these compositions, in as much as, absorption and retention of liquid oxygen in the cartridges were not properly regulated in the fine pores and in the inter-granular spaces inside the ingredients in a uniform manner.

Jan 1, 1989

By Zhang Yangde

"This paper reports the clinical research work of Micro-explosion of Biliary Calculi . In theprogram the technique of directional micro explosion applied to disintegrate the biliarycalculi of body and decreases the rate of operation. Up to the present, 235 cases of biliaryduct calculi have been successfully treated by use of implusive force of micro-explosion .The success rate of blasting stones was 100% by the use of the directionalmicro-explosive instrument made by us , the once success ratio of micro-explosion was93.2% and tl~o rmulb of treatment were satisfactory. . Considering the density of theblood vesselsiD the human liver, limitation of space in the h~patic.ducb, the securiey andadaptation, we have designed two types of micro- explosives equipment called ZS device,electric initiation and nonelectric initiation to initiate explosion. The head diameter of thedevice ie 1.5-1.8 mm . It is applicable to all kinds of fiber endoscope by inserting ZSdevice under grossing eyes or TV set ."

Jan 1, 1993

By Shawn Kirkpatrick, Yang Ruilin, Tamara Whitaker

In order to manage blast vibration in soft ground containing large diameter holes and large charge weights, a number of issues must be considered. This paper describes techniques to control and reduce near-field blast vibrations absorbed by highwalls in soft ground. Sympathetic detonations need to be controlled. Sympathetic detonations can cause excessive vibration due to an unknown number of charge weights firing out of sequence. The excessive vibration can cause damage to the ground. Sympathetic detonations can be controlled through proper design of blast patterns and, in some cases, through the use of specialized electronic detonators.

Jan 1, 2009

By B R. Spencer

Using bulk repumpable water gel explosives in underwater shooting results in even more benefits to the user than a "dryland" customer. It is nearly impossible to reshoot underwater, so a bad shot causes tremendous problems. The huge expense of operating drill boats, dredging buckets and clamshells makes shot loading, hookup and digging cycle times critically important.

Jan 1, 1990

By Robert L. Martin, Brian W. Stump, David P. Anderson, David Gross

In an attempt to better understand the impact that large mining shots will have on verifying compliance with the international, worldwide, Comprehensive Test Ban Treaty (CTBT, no nuclear explosion tests), a series of seismic and videographic experiments has been conducted during the past two years at the Black Thunder Coal Mine. Personnel from the mine and Los Alamos National Laboratory have cooperated closely to design and perform experiments to produce results with mutual benefit to both organizations. This paper will summarize our activities, highlighting the unique results of each.

Jan 1, 1997

By Yves Lizotte, Malcom Scoble, Sanu Hanspal

"This paper reviews the physical, chemical and mechanical components of what is considered to be the anatomy of a blast muckpile. These relate principally to geometry, floor, fragment size and shapedistribution, density, hydrology, weathering, and diggabiity characteristics."

Jan 1, 1995

By George E. Jackson

ANFO, as a blasting agent, is used in large quantities in coal surface mines. It can be purchased on the open market or through reliable suppliers. The blaster in the field must assume that his ANFO is homogeneous, consistent, and nearly identical on a daily basis. A quality control program will enable him to be assured of the correct product. Therefore, the material cost and operational efficiency can be better controlled.

Jan 1, 1978

By Virgil J. Stachura, Larry R. Fletcher, Matthew N. Plis

Falls of ground remain a leading cause of fatalities and injuries in underground mines. In response to this situation, the Bureau of Mines conducted a series of experiments in the White Pine room-and-pillar copper mine which resulted in smoother, safer ribs due to a reduction in the amount of overbreak caused by blasting. The tests evaluated the effects of changes in the loading of the rib holes of the mine's 20- by 28-ft drift round driven in shale and sandstone. The relative integrity of the ribs remaining after the blasts was measured using both photographic and seismic refraction techniques.

Jan 1, 1989

By P. Katsabanis

Numerical modelling was used to examine damage in wall control operations. Decoupled charges appear to create larger damage zones than fully coupled low density charges with similar charge distributions: Air was shown to be a very efficient coupling medium, while water coupling resulted in significant damage. However, Mach stems are formed when air is used as a decoupling medium, leading to compression of the charge ahead of the detonation wave. Air decked charges generate two damage zones, one close to the charge and another close to the air-deck/stemming interface, where pressure pulses are reflected. The extent of the latter depends on the length of the air-deck.

Jan 1, 2001

By Thomas A. Simpson, Yung-Kwaun Jow, Dennis L. Gamble

Construction of the $200 million Riverchase Galleria Mall in Hoover, Alabama was started in early 1984. The construction area consists of about 70 acres. The extensive building complex requires heavy concrete foundations which have to be poured during the early stages of construction and on a nearly daily situation so that contractual agreements can be met on a timely basis.

Jan 1, 1985

By R W. Givens

This paper presents blast casting design variables that have been developed and are currently being used at the High Power Energy mine in West Virginia. The shot specifications are summarized in Table I. The two active casting pits were designed with casting in mind and as a result are better designed and more efficient. About 55% of the overburden material is effectively cast and clean up is done by a bulldozer, front-end-loader, and trucks. This results in a 15X decrease in the cost of coal production.

Jan 1, 1988

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