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By Chris Breeds, Ken Johnston, Omar Fulton

This paper describes the process typically involved with obtaining permits for quarry blasting in urban, suburban, and rural areas, including: content of SEPA (State Environmental Policy Act) driven documentation; regulatory review and comment; public interaction; public hearing(s); periodic regulatory review(s); negotiated solutions; monitoring; and the role of public interaction, demonstration(s), and education in the process. Case studies will be presented of projects undertaken in the State of Washington that illustrate the approach and regulatory interaction as well as the importance of public interaction throughout the process. Reference will be made to the role of national and state regulations and local codes and ordinances that provide additional limitations on blasting practice. The paper will also present regional blast monitoring data that are used in the permitting process and the layout and design of blast monitoring systems typically required as conditions of the quarrying permit. Our presentation will include tools, which we have developed to assist with explaining blast related phenomenon to both regulators and the public.

Jan 1, 2003

By Jack Eloranta

This paper documents the relationship between material handling and processing coete compared to blasting cost. The old adage, "The cheapest crushing is done in the pit", appears accurate in this c!ase study. Comparison of the accumulated cost of: powder, selected wear materials and electricity; indicate a strong. inverse correlation with powder factor (lbe powder/long ton of rock). In this case, the increased powder cost is more than offset by electrical savings alone.

Jan 1, 1995

By Braden Lusk, Paul Sainato, Josh Calnan, Hiago Vasconcelos, Luis Felipe Marinho

"Blasting and rock fragmentation is one the most important unit operations in mining. Since itsintroduction into the mine production cycle, mining has become more efficient in mineral production(Hartman, 2002). Widely used with the main objective of breaking rock mass in smaller fragments to be loaded and hauled at a minimum cost, blasting is optimized when stemming materials properly confine drillholes charged with explosives. Halim Cevizci (2013) performed a stemming application using Gypsum plaster, a kind of material that exhibits solid-like behavior when it is dry. Based on his theory, the present article reports an experiment using another type of material that shows similar behavior, non-Newtonian fluids. The primary goal of this study is to measure the confinement effectiveness provided by a non-Newtonian mixture as the stemming component. The study also analyzes the explosives’ energy propagation throughout the rock mass relating to the stemming materials applied. Currently, mining literature recommends the application of dry granular materials in stemming columns, because of its inertial and high frictional effects (Hagan, 1973). However, the test verified that the mixture added to the stemming column was able to reduce energy and gas losses to the atmosphere, because of the liquid’s property of filling voids in the material. The solid-like behavior of the non-Newtonian mixture was investigated for its capability to improve borehole confinement, since the mixture reacts like a solid when under shear stress. The results were compared to those from sand and air stemming applications, configured in different arrangements. It was concluded that the non-Newtonian mixture yielded high results due to its better confinement effectiveness, a reduction of air overpressure, and an increase of the strain propagation and ground vibration throughout the rock."

Jan 1, 2016

By Steve Dillingham

The horrific events surrounding September 11th left Americans with a feeling of sudden helplessness...the shock of being unprepared and powerless. From this tragedy, we can understand the need to prepare for the unexpected, and can apply this hard lesson into operational planning for those involved in the commercical explosives industry.

Jan 1, 2003

By Randall M. Wheeler

"Fourier analysis is a very powerful frequency analysis tool. However, it is frequently misunderstood and sometimes used inappropriately. Part of this workshop will involve the basics of Fourier series, the Fourier integral and finally the Fourier transform. Included will be a brief discussion of analysiswindows, including the box and Hamring windows."

Jan 1, 1998

By Brian W. Stump, David P. Anderson, John Wiegand

Mining explosions are designed for a variety of purposes including the fragmentation and movement of materials. The blast design is dependent on the particular application intended and the material properties of the rock. The range of mining applications from hard rock quarrying to coal exposure to mineral recovery leads to a great variety of blasting practices.

Jan 1, 1997

By George Boucher, Simon Williams, Neil McBride

"The aim of these analyses was to utilise the latest available production information for the Wandoooperation to determine the optimal blasting parameters, costing’information and predicted results(fragmentation, muckpile shape and vibra.tton). Much of the data used as input was made availablefrom the information gathered during the excavation of the test pits during 1995. As with any“planning stage” analyses, many assumptions were required to fill gaps in the available data."

Jan 1, 1998

By Abigail Styer, Paul Holmgren, Josh Calnan

Detonating cord is a staple of the explosives industry, used widely in the civil and defense industries. Detonating cord is a thin, flexible plastic tube filled with pentaerythritol tetranitrate (PETN). It has many applications in mining, construction and military disciplines. For civil applications, it is used to connect and initiate a series of blastholes in a desired pattern. In the defense sector, it can be used as a detonating agent, a priming agent or alone as an explosive charge. Research has been done to understand the initiation and detonation physics on the detonating cord. However, its sympathetic detonation characteristics needed to be further analyzed. The sympathetic detonation of the detonating cord can lead to the poor performance of production shots in mining or civil applications and unsafe conditions in defense applications. This paper focuses on the analysis of different factors involved in the sympathetic detonation of various sizes (grain weights) of detonating cord. The variables analyzed include the minimum distance between segments of detonating cord and grain weights. These variables were analyzed by securing segments of detonating cord at measured distances apart on a steel plate and detonating them. The physical examination of the aftermath of this detonation included a qualitative recording of data. Applications of detonating cord that could be affected by this research include mining and construction blast initiation, explosives disposal, and breaching.

By William D. Hissem

For those blasthole applications which require the use of holes ranging from 1” to 5.5” in diameter, the use of top hammer drills has been the equipment of choice for several generations of drillers. Pneumatic compressed air and hydraulic compressed oil systems represent the primary technologies which are available to the drilling practitioner. While both employ the same operating principals, the characteristics of performance, cost, and reliability can be markedly different between technologies and manufacturers.

Jan 1, 1998

By David M. Langlais, Krystle Pelham

"Explosives used in blasting operations, natural and anthropogenic sources such as septic systems,fertilizers, and decomposing vegetation can potentially contaminate groundwater with nitrate in thevicinity of construction sites and make identification of blasting impacts difficult. Blasting operationsfor a private construction project in Windham, New Hampshire were indicated as the source of water quality impacts to private drinking water wells prompting the New Hampshire Department ofTransportation (NHDOT) to implement a proactive approach to limit the potential for impacts fromblasting for ongoing NHDOT projects. NHDOT has developed a baseline drinking water monitoringprogram designed to detect potential impacts and to ensure alternative drinking water is providedthroughout the construction phase of projects. In 2013, the U.S. Geological Survey (USGS) andNHDOT began a study to determine the source and fate of nitrogen compounds near blasting sites using a combination of isotopic, time series, geochemical, hydrologic, and geologic data. Approximately 1.75 million cubic yards (1.33 cubic meters) of rock were removed by blasting in several locations for roadway construction at a major highway construction site in southern New Hampshire."

Jan 1, 2016

By Robert Morgan

With improved methods for designing and detonating shots the potential for flyrock can be significantly decreased, but there are few absolutes in blasting; therefore blasters must learn from the mistakes of others. Blasters must conscientiously employ control measures to minimize the risk of flyrock. The worst case incidents which tend to be widely reported by the media, should serve as a reminder to us all that minimizing the risk of flyrock must be incorporated into the design of the drill pattern and blast design.

Jan 1, 2001

By Derek T. Novotny

Blasting cap precision is of major importance to advanced blast design. New technologies have introduced the use of microchips within detonator casings in the hope that the electronic control of the timing element will increase the accuracy of the cap and therefore improve the results of perimeter control blasting applications. The electronic detonators have proven to be accurate in timing tests done to date. They boast cap scatter results to microsecond accuracy, but the question is, does this degree of accuracy actually prove to be beneficial during practical use in the industry, or are conventional technologies applicable.

Jan 1, 1998

This paper is concerned with the blasting of rock in mining. The most common purpose of blasting rock is to cast it or to disrupt its structure sufficiently for effective digging and subsequent removal.

Jan 1, 1991

By Brian W. Stump

"Seismic waves from explosions can be used to characterize physical processes in and around the source. The quantification of absolute levels of ground motion is important for minimizing impact on nearby people and structures. We contrast work in characterizing seismic radiation from contained nuclear explosions with ground motions from multiple explosion quarry blasts. A physical basedunderstanding of the explosion source function allows prediction and extrapolation to new environments where experimental data may not exist."

Jan 1, 1990

By Douglas Bartley, Robert McClure

This paper discusses the advances in programmable, testable high accuracy electronic detonator technology. The operation and safety of electronic detonator systems are required to meet rigid safety standards and withstand the demanding environment of in-field applications. These requirements are discussed through comments on existing safety requirements in Europe.

Jan 1, 2000

By William G. Szymczak

A set of experiments were conducted at the Aberdeen Proving Grounds [1] in which explosive charges were buried in saturated sand beneath a suspended rigid platform. The goal of these experiments was to measure the dependence of the impulse transmitted to the platform on the standoff distance and the charge burial depth. Simulations of these experiments were performed using the BUB2D axi-symmetric code using a frictional-cohesive visco-plastic model to describe the response of the saturated sand. This code solves a constrained set of conservation laws in which the liquid region (in this case saturated sand) is assumed incompressible. The explosion is initialized as a high pressure gas bubble (void) within the fluid. Comparisons of the simulations to the experiments are presented together with a study of the physical phenomenology associated with the loading process. In particular, it is shown that the force imparted to the platform is a combination of the impact of the sand on top of the explosion gas bubble and the pressure of the bubble as it expands before venting into the atmosphere. Under certain conditions, when the platform standoff is sufficiently small and the platform is sufficiently large, the bubble can over-expand before venting and pull the platform downward. This phenomenon was studied further through carefully measured and photographed small-scale experiments performed at the University of Maryland [2]. The small-scale experiments provide additional important validation benchmarks for our model.

Jan 1, 2005

By Robert Hopler

Testing Stations Abroad At the Seventh International Congress of Applied Chemistry, Drs. Mente and Will communicated a paper on the above subject. All large coal-getting countries employ testing stations of some kind, in order to safeguard, to the highest possible extent, the lives of the men employed in this industry. Most countries employ galleries of considerable diameter, and fairly short length; but within recent times, long galleries, with drives and other accessories approaching as closely as possible the actual conditions of mining have been installed. The following are the details of the testing stations employed in the countries mentioned.

Jan 1, 2010

By Matt Slezak, Tristan Worsey, Nathan Rouse, Kyle Hall

As everyone knows, blasters are required to file blast reports of every blast for regulatory purposes. To this day, the authors see many handwritten blast reports. Handwritten blast reports are notorious for containing errors or omissions. This is not because the blaster intends to misreport information. It is because blasters have many tasks to complete in a day, are sometimes in a rush, and could accidentally miscalculate data, omit items, or record incorrect data. In most cases, blasters do not suffer consequences to these errors because blast reports are seldom reviewed in detail. In some cases, such as when a blasting operation undergoes some sort of litigation process, the reports are reviewed in detail and the blaster is ultimately held responsible. If the reports contain errors, the blaster can be fined, have his/her license revoked, or worse. Electronic blast reporting and centralized data management can help reduce or eliminate the potential for accidental blast reporting errors to occur. This paper presents many ways that electronic blast reporting can reduce or eliminate blast reporting errors, decrease time and extra costs spent reporting, and improve efficiencies in the field and the office.

Jan 1, 2018

By Bruce Vandenberg, Andy Battfay, Don Lake, Steve Conway, Jeff Yorsz

"High-speed motion pictures are an invaluable resource for blasting analysis. Whether processed by the human eye or a computer, this imagery can provide important insight into a blast and its effects.While certainly popular, traditional high-speed film cameras hamper this process. Instant feedback is not available since film requires developing and, relevant in the case of automated analysis, film isnot immediately compatible with a computer. With these facts in mind, a new high-speed video camera system, the SVCSOO, has been developed. The SVC500 combines the capabilities of a high-speed film camera, the convenience of a solid-state digital video camcorder, and the computing power of a ‘486 PC to provide a complete, standalone platform for high-speed image acquisition and analysis. This paper will describe the design, features, and use of the SVCSOO andcompare these with the analogous aspects of film cameras."

Jan 1, 1994

By Trevor Howie, Mal Edwards

"Thiess Contractors Pty Ltd. designed and operate the Mt Owen Mine in the Hunter Valley of NewSouth Wales, Australia on behalf of the owners of the mine, BHP Coal Pty Ltd. The mine is a multiseam open cut coal operation. Mining by Thiess commenced in September 1996 following thecompletion of the coal preparation plant. The location of the mine is shown below on Figure Al."

Jan 1, 1997