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By Corry Goumans

The job location is at Bear Lake Hydro Project located north of the town of Sechelt, British Columbia, Canada

Jan 1, 2013

Bloomfield Collieries Rix’s Creek Mine is an open cut coal operation located in the Hunter Valley region of Australia. The mine produces approximately 1.1 mt of saleable product per year and routinely employs cast-blasting practices for its unique dragline-truck overburden excavation method.

Jan 1, 2006

By Albert G. Funk, Gary M. Thornley

The available energy of aluminized ANFO and aluminized slurry blasting agents has been measured by seismic methods, calculated theoretically, and compared. With aluminized ANFO it is concluded that aluminum concentrations should be restricted to less than 10 percent because of diminished energy yields at high aluminum concentrations. However, with aluminized slurry it is concluded that efficient use of aluminum can be made at aluminum concert"rations up to 18 percent. It is further concluded that the difference in efficiency of use of aluminum by these two classes of blasting agents results from a higher contribution to useful work from the condensed detonation products of the relatively higher density aluminized slurry blasting agent.

Jan 1, 1981

By Doug Wathen, Philip M. E Thomas

The City of Fort Myers needed to replace a 40-year old 42-inch storm sewer line in downtown Fort Myers with a new 54-inch line to accommodate population growth. The old line had to be kept operational while a new line was installed. The contractor spent two months using a drop ball, a hoe ram, and large rippers trying to break the three to four feet of rock that needed to be removed to accmmodate the new pipe. Mechanical trenching was considered but was proven to be overly expensive. On very short notice, Ireco of Florida was asked to design and execute a blasting procedure that would allow this project to proceed. Nearby buildings were over 80 years old, three of them containing antique shops specializing in glass antiquities with attorney offices above them. High water table compounded problem with a 20-year old steel water main and clay drainage pipe 15 feet frcan the new sewer line. Holes had to be drilled within six inches of the edge of the existing pipe to four feet below the pipe on either side of the pipe and blasted. No interruption in the sewer line flow was to be tolerated.

Jan 1, 1996

By W. Reisz

The fear of heights is a natural defense against performing a dangerous and unnatural act such as standing on the edge of a hundred foot wall. Yet through familiarity, a casual attitude often exists. Those of us, who work near highwalls on a daily basis, may become overly comfortable in our surroundings, losing sight of the disaster which may often rest a single misstep away. And this is where the hidden dangers lie.

Jan 1, 2009

By Jesus A. Pascual de Blas

After 30 years of development and introduction, electronic initiation systems are now well established in blasting applications, both mining, quarrying and civil works. In terms of blast technology, it could be considered that timing is the new challenge: how to define the most appropriate sequence to improve fragmentation, reduce vibrations, avoid dilution, eliminate damage… Some classic tools have been updated and adapted to the new scenario, and are giving us good performance; on the other hand, others should be considered obsolete, given the accuracy of electronic initiation systems has exposed these tools to incoherent conclusions. Besides, other tools have appeared and are in use, providing new approaches to old issues. Additionally, not only the technical side has to be considered: safety, security, economics are well present in daily blasting activity and affect to the final decision: are electronic initiation systems the right answer to my blast?

Jan 1, 2019

By Jan Mehren, Arild Neby

Underwater Tunnel Piercing or Lake Tap, often also called the Norwegian Method, will in many projects be an important part of the hydro electric development scheme. The very last blasting round in the Lake Dorothy Lake Tap Tunnel, which penetrated into the lake at a depth of 120 ft (36 m), was such a key step in constructing the Lake Dorothy Hydroelectric Project. A lake tap project is multidisciplinary. Besides the pure blasting and construction technique aspect, engineering geological and geometric considerations that aim to optimize the tunnel alignment making a lake tap possible at minimized risk are of significant importance. Output data from numerical model analysis of the hydrodynamics resulting from the blasting is vital for the final adjustments to the geometrical layout. The planning of monitoring systems for the surveillance of hydrodynamic impact on valves and pipes as well as control with water levels and air pressures prior to and during the blasting, are all additional crucial elements in the design. More than 600 lake taps have been successfully performed in Norway since the 1890`s. The technique, which deserves to be called well proven, has been applied mostly in the hydropower sector but over the last 20 years also for shore approaches in the oil and gas industry. The demand for this technique seems to be ever more growing.

Jan 1, 2009

By Thomas Rupp, Michael Siegwart

The paper presents the vibration and sound emission measurement campaigns carried out in 2007 in preparation for the Ceneri-Basistunnel construction. We also present the vibration measurement campaign conducted during the construction of the Zimmerberg-Basistunnel. Both tunnels form an integral part of the Swiss Federal Railway Company Neue Eisenbahn Alpentransversale project (NEAT). This strategic project comprised the construction of several new tunnels. Its aim is the improvement of the existing infrastructure. The improved infrastructure will be able to accommodate a larger volume of railway traffic that is also crossing the Alps at higher speeds. The construction of the Ceneri-Basistunnel commenced in 2006. Both the Zimmerberg-Basistunnel and the Ceneri- Basistunnel are located underneath densely populated areas. Therefore, noise and vibration emissions have to be kept to a minimum and must not exceed applicable codes of practice. In order to identify the most appropriate blasting strategy for the yet to be constructed Ceneri-Basistunnel, blasting trials were conducted. The paper presents the findings of these trials and identifies ways to reduce both noise and vibration emissions from blasting. The construction of the first phase of the Zimmerberg-Basistunnel took place between 1999 and 2003. While the first phase is already in operation, the construction of the second phase has been postponed (commencement originally due in 2007). The Zimmerberg-Basistunnel connects the outskirts of Zürich with the city centre. As the tunnel site was not located close to the surface near populated grounds, no special measures were needed to reduce the noise emissions from blasting. However during the construction of the tunnel, the vibration emissions from blasting were monitored on more than 50 locations on the surface. The paper presents the analysis of some of the data. An emphasis is placed on the appropriate synopsis and presentation of data for documentation purposes.

Jan 1, 2009

By Romel Villanueva, Juan Vasquez

We present the results of our field research on the variation of the density of the gassed explosives and their influence on the blasting results in the Peruvian mines: Yanacocha, Toquepala and Antamina. Currently, 90% of Peruvian mines uses gassed explosives, for their economic and technical benefits. But new practices and design criteria have had to be adopted, and the most important a careful control of the in-hole density, whose variation in the depth of the hole strongly affects the detonation process. For gassed explosives the density varies gradually according to the depth in the hole, due to the pressure on the bubbles by its own weight. The density at the bottom of the hole can reach critical values, which directly affects the start of the detonation in the booster zone with a high probability of nitrous fumes formation. On the other hand, density translates into the amount of explosive and energy available. Therefore, for the optimum performance of the explosive, the minimum and maximum values of the in-hole density must be determined. For the cases studied, the maximum in-hole density and the maximum charge length have been determined. When the charge length is greater than 7.0 m [ 23 ft.] special care must be taken with the cup density, which as a general rule should not exceed the value of 1.15 g/cm3 [71.8 lb/ft3] at the risk of losing the sensitivity at the bottom, also increasing the probability of nitrous fumes, bad fragmentation and finding intact explosive after blasting. In the large holes in Toquepala and Antamina mines, where the charge length can be greater than 9.0 m [29.53 ft]. If the cup density is greater than 1.15 g/cm3 [71.8 lb/ft3] the in-hole density can easily reach a high value of 1.30 g/cm3 [81.16 lb/ft3].

By Terri Jordan, Kenneth Hollingshead, Mary Jo Barkaszi

The Port of Miami, Miami-Dade County, Florida (Port) is the largest container port in the State of Florida. However, it is located in the center of a diverse ecosystem. Biscayne Bay surrounds the Port and portions of the bay have been designated as a National Park, a Florida Aquatic Preserve and a state Critical Wildlife Area. The bay is home to many protected, threatened and endangered species including the Florida manatee, five sea turtle species, American crocodile and bottlenose dolphin, in addition to important recreational and commercial fish species.

Jan 1, 2007

By Stuart Brashear, Lee Schettler

"The effect of water on several ANFO/emulsion blend ratios is documented by both physicalobservations and analytical testing to demonstrate the effect even small quantities of water canhave on water resistant blends."

Jan 1, 1996

By John M. Bolger, Keith E. McMaster

Excessive salt fines are undesirable in underground salt mining as they are considered a costly waste byproduct. This paper describes an extensive explosive application program conducted at The Canadian Salt Company Ltd, located in Pugwash, Nova Scotia, Canada. The prime objective of the program was to reduce the quantity of fines generated from this company’s underground production blasts. The program was known as the “The Fines Reduction Program”.

Jan 1, 1996

By Douglas R. Burns

Complying with SARA-Title III and the Emergency Planning and Community Right-To-Know Act as a Non-Manufacturing Facility. As of August 23, 1988 non-manufacturing facilities storing end using chemicals which require MSDS (Materia1 Safety Data Sheets) must fi1e with SERC (State Emergency Response Commission), the LEPC (Loca1 Emergency Planning Commission), and the loca1 Fire Department a list or copies of all MSDS sheets with the Tier I and Tier II forms completed.

Jan 1, 1989

By Michael K. Phang, Thomas A. Simpson

Field studies at an underground mine site were conducted to evaluate and monitor blast-induced vibrations on an underground coal mine roof. The vibration data were evaluated so that a suitable damage criteria or guidelines from which a safe operating distance between surface blasting and underground mine operations can be established.

Jan 1, 1984

By W. J. Birch, R. Farnfield

All shock-tube based initiation systems have a time lag relating to the propagation velocity of the shock-tube itself. This paper examines the exploitation of this inherent time lag to achieve delay blasting with accuracies approaching that achievable with electronic systems albeit over a much shorter delay range. The system employed consists of a combination of standard shock-tube, plain detonators and various shock-tube branching components. The accuracy of the complete system depends on the scatter in delay time induced by each component. In order to quantify this scatter a series of trials were undertaken to determine the variability for each component. These trials are described along with a detail statistical summary of the data recorded.

Jan 1, 2009

By Trevor Ames

Highwall instability, and sometimes referred to as ground failures, historically are a consistent contributor of mine injuries and fatalities within surface mines. To combat this several efforts, including those from NIOSH (CDC), to educate the mining community with insightful literature focused on hazard recognition and advances in ground monitoring systems have been performed. The question is can more be done or is this our last line of defense to manage potential dangers? Is there a more effective method to reduce hazards presented by ground failures including rockfalls?

Jan 1, 2015

By J T. Schamaun

Recent applications of explosives and blasting agents to rubble rock have led to requirements for more elaborate design and analysis methods. In most blasting uses, it is necessary not only to fracture the rock, but also to move the broken rubble in a predictable manner. Many in situ extraction techniques require; rubblization to take place in a confined region where rock motion is a predominate factor in creating a permeable broken bed. In this paper, an engineering model is presented which describes the large rubble motion during blasting. This model is intended to provide the blast designer with a tool for evaluation and further refinement of blasting patterns and timing sequences.

Jan 1, 1983

By R Heater, G Glynn

Various small diameter commercial grades of slurry and emulsion explosives were tested and compared. Velocity diameter curves for confined and unconfined charges were established and the effects of temperature and hydrostatic pressure on critical diameters and minimum primer weights were determined.

Jan 1, 1984

By Michael Louis, Charles Dowding

Concern over construction vibration-induced cracking has led to development of a new approach to vibration monitoring called autonomous crack measurement (ACM) and illustrated in Figure 1. This paper describes the concept as well as sensor performance in the first test house fitted an ACM system. Response of three cracks in this concrete masonry unit (CMU) house was measured as part of the system verification. ACM employs a single sensor that measures both weather-induced micrometer changes in crack width and those produced by habitation and ground motioninduced vibration. This comparison is displayed in real time via the Internet without human interaction. Graphic display through the Internet provides a new pathway for communication with the public. Such visual comparison of changes in crack width provides a simple alternative to the present system of comparison of measured and allowable vibration time histories. Measurements reported herein show that weatherinduced response of cracks is greater than that caused by presently allowable construction-induced vibration.

Jan 1, 2003

By Richard Mainiero, James H. Rowland III

For many years there have been small scale tests available for evaluating the toxic fumes production by capsensitive explosives (DOT Class 1. l), but these could not be used with blasting agents due to the large charge sizes and heavy confinement required for proper detonation. Considering the extensive use of blasting agents in construction and mining, there is a need to determine the quantities of toxic ti,tmes generated by blasting agents. At the International Society of Explosive Engineers Twenty Third Annual Conference on Explosives and Blasting Technique in 1997, the authors reported on a facility for detonating large (4.54 kg), confined blasting agent charges in a controlled volume that had been constructed at the National Institute for Occupational Safety and Health’s Pittsburgh Research Lab’s Experimental Mine. Since 1997, this facility has been used to collect data on toxic fumes produced by the detonation of various ammonium nitrate/fuel oil (ANFO) mixtures and several cap-sensitive explosives. ANFO composition ranging from 1 to 10 percent (pet) tieI oil have been studied. As expected from previous studies, with an increase in fuel oil content the carbon monoxide production increases, while nitric oxide and nitrogen dioxide production decrease. The detonation velocity varies from 3,000 to 4,000 m/set for the 1 to 10 pet range of fuel oil content, suggesting that ANFO mixes with improper fuel oil content may appear to detonate properly, while their fume production differs significantly from optimum. The study also considers such factors as degree of confinement, water contamination, and aluminum content on blasting agent fume production. Results indicate that water contamination of the ANFO has little effect on carbon monoxide production, but causes significant increase in nitric oxide and nitrogen dioxide production. Decreasing confinement from Schedule 80 steel pipe to 0.4~mm thick sheet metal also has little effect on carbon monoxide production, but significantly increases nitric oxide and nitrogen dioxide production. Adding 5 and 10 pet aluminum to the ANFO had no clear effect on carbon monoxide, nitric oxide, or nitrogen dioxide production.

Jan 1, 2000