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By Walt Meglasson

The Kaiser Aluminum Company Smelter, one of several in the Pacific Northwest, was built in 1942 and operated by the Olin Company during World War II and then purchased by Kaiser Aluminum after the war. At its height, the facility employed over 350 workers and was capable of producing 73,000 tons of aluminum per year. It was closed in 2000 through a combination of rising electrical and labor costs, and the inability to compete with more up-to-date foreign facilities.

Jan 1, 2008

By Sami Kara, Marsel Nabium

This paper provides an overview of the solution applied in underground Silver mine in Russia. The paper reviews the dilution problem throughout the entire mining process, and provides a rational approach to underground mine Blast design in order to minimize dilution

Feb 1, 2020

By Dipankar Gorain, A K. Vishwakarma, Vivek K. Himanshu, Murari P. Roy, Shubham Singh, R S. Yadav

The industrial establishments of a power plant consist of many important structures viz. cooling tower, wagon tippler, track hopper, plants and offices. The leveled foundation is the utmost need for erecting these structures. The leveling of the foundation is done by rock excavation, when the establishments have to be setup in hilly/rocky areas. Drilling and blasting is the cheapest and most dominant method of rock excavation. However, this method has associated hazards in terms of blast induced ground vibration, air overpressure, flyrocks etc. The foundation work and erection of the industrial buildings are done in parallel to achieve the faster construction of the establishment. The challenges to reduce the induced hazards in such cases are more. This paper presents a case study on the controlled blasting method devised for the rock excavation for construction of 2 × 660 MW Obra-C thermal power plant. The foundation work for this power plant was made by excavation of Dolomitic rock. The excavation work was performed in the proximity of the existing residence of the local people and Obra market. With the advancement of project, the excavation was also performed in the proximity to the ongoing construction work of various industrial buildings. Accordingly, the controlled blasting pattern was devised suitable to the specific sites. The pattern consisted of variations in blasthole diameter, burden-spacing, maximum explosive charge per delay, total explosive in a blasting round, initiation system and direction of initiation. The suitable muffling arrangements were also used, when the blast was conducted in the close proximity to the structures. The initial blasting pattern was established by analysis of blast vibration wave propagation characteristics. Thereafter, the final pattern was adopted for the safe excavation at the site. The safe excavation for the foundation work of this power plant has been completed successfully based on the devised controlled blasting pattern.

Feb 6, 2023

By Dennys Huaman, Carlos Rojas

Using the Levenberg-Marquardt algorithm to reparametrize the Kuz-Ram original model equation of the mean characteristic size and assess the errors of both models and their comparisson using different statistics measures like chi-squared or relative error with the usage of the Monte-Carlo algorithm.

Feb 1, 2020

By Sami Kara, Marsel Nabium

As a mining project is developed from conceptual to production phases, there exists a variety of uncertainties and difficulties that affect the operation’s designs and economic values. A notable design parameter to be taken into account is the factor of dilution. Dilution is the waste material not separated from the ore in the stages of mining and is sent to the processing plant. It is defined at the ratio of tonnage waste mined and sent for processing over the combined ore and waste tonnage milled. Dilution reduction is one of the areas that offer metal mines an opportunity to increase revenue and reduce costs, resulting in enhanced profits. Effective dilution control programs require interaction on a multidisciplinary level. This paper outlines recent initiatives undertaken at Polysmetal Silver Magadam Mine to reduce dilution and increase revenue. This paper provides an overview of the solution applied in underground Silver mine in Russia. The paper reviews the dilution problem throughout the entire mining process, and provides a rational approach to underground mine Blast design in order to minimize dilution. The mining companies put a lot of effort into extracting lower grade while minimizing cost. The dilution control assists with achieving this goal. In Polymetal Silver Magadam Mine we succeeded to control more than 20 blasts by keeping almost the same grade measured in the face. The results indicated that using the adequate blasting timing design can help to separate the ore from the adjacent waste in drift blasting with different ore body configuration.

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 Jacqueline Berendzen

Summer internships are a great way for students to explore different career paths in the industry and get first hand experiences with potential employers. As a junior in mining and explosive engineering, my 2009 summer internship gave me a behind the scenes view of the actual workings of an explosive company and the role they play in the mining industry.

Jan 1, 2010

By Walter Valery, Sarma Kanchibotla

Due to the global financial crisis, the world economy has turned upside down and most major economies in the world are facing severe recession for the past one and half year. During this period most commodity prices have tumbled by more than half from their peaks and such a sudden and severe economic downturn is not seen since the great depression. This sudden drop in commodity prices and lack of credit made many mining operations unviable and even those mines that are marginally viable at this point are operating under severe cost pressures and capital expenditure restrictions.

Jan 1, 2010

By David N/A Doucet, Colter N/A Angell, William N/A Joa, Kyle N/A Wagner, Catherine N/A Johnson, Marty N/A Langenderfer

The Kingery-Bulmash (K-B) equations are a widely accepted means of predicting air-blast parameters from surface explosive detonations. The parameters predicted from these calculations include incident and reflected pressure, time of arrival, shock front velocity, incident impulse, reflected impulse, and positive phase duration. K-B calculations are based on curve fitting of experimental data and can be used to predict air-blast parameters for explosive weights from less than 1 kg (2.2 pounds) up to 400,000 kg (440.9 US Tons), and ranges of 0.05 to 40 meters (1.9 inches to 131.2 feet). The K-B equations can also determine the parameters for multiple explosive types using scaled distances and relative equivalency to TNT. An experiment was designed to demonstrate if the measured results for incident pressure, time of arrival, shock front velocity, incident impulse, and positive phase duration equal the expected results reported for the detonation of a small quantity of explosive determined by the K-B Calculator. Three surface-detonated 300-gram (0.66 pound) hemispherical charges of Composition C-4 were observed via high-speed imaging and hydrostatic pressure monitoring. The hydrostatic pressure generated from each charge was measured via piezoelectric pressure transducers at a scaled distance of 10 from the charge epicenter, and at elevations of 0.30, 0.61, and 1.22 meters (1, 2, and 4 feet) above ground level. Variances in experimental values from the K-B predicted values were recorded for each measured blast parameter. Time of arrival, which was redundantly confirmed through high-speed imaging analysis and hydrostatic pressure monitoring, showed the highest deviation from the predicted values at more than double the K-B predicted value. This report compares the observed blast parameters from the test series with the expected blast parameters from the Kingery-Bulmash Blast Parameter Calculator. Differences between the experimental and predicted values are reconciled through analysis and discussion of testing conditions, instrumentation setup, and scaling methods.

Jan 1, 2019

By K. Best, D. Conn

The US Army Corps of Engineers KY Lock Project in western Kentucky presented the blasters and vibration consultants with a set of unique challenges. The blasters on this project were faced with difficult geology and joint set orientation and sequencing of blasts opposite from what the explosive engineer/blasting specialist had recommended. Combining these issues with strict vibration and air overpressure specifications, blasting as close as 7 feet (2.1 meters) from a new lock wall, site topography that influenced the air overpressure, limitations on seismograph geophone placement that led to anomalies in seismograph recordings; surprising lessons were learned by everyone involved in the project and it is the authors’ goal to share this valuable information with everyone in the blasting industry.

Jan 1, 2024

By R. Jacob

Mining has been around for a long time, and new deposits are being discovered continually but are becoming more complex for processing and typically sulfide in nature. Most of the large easy deposits with simplified and cheaper to process oxide material have been mined or the deposits are locked up with legal or social issues and may never be mined. It is common to see the mines today being evaluated to mine have little in oxides and have a sulfide component to the deposit. This creates a problem with explosives being selected for the mine because ANFO could cause a reactive ground issue. When evaluating the cost component of mining for future mines, ANFO is the go-to selected bulk explosive because of the cost and effectiveness. More work needs to be done by projects evaluating costs by properly testing the ground and water conditions to match the correct bulk explosive for the ground conditions of the mine. This will prevent a possible safety hazard and the best result for the mine.

Feb 6, 2023

By Jeffrey Loeb

Recent trends in blasting engineering and its related fields, at the level of professional academia, have tended to exclude detailed discussion and examination of the formative experiences of the engineering student. In particular, the extra-curricular aspects of the undergraduate program in engineering—focused, in this case, on the summer job—will be shown to contain a wealth of heretofore underappreciated knowledge in the field. In Surveying the Damage: Post Traumatic Stress and Pre-Blast Surveys, I intend to outline and examine some of the more unusual experiences afforded me by my work as a preblast surveyor in the summer of 2007. In this capacity, I was required to make a visual note of existing conditions of surrounding residential and commercial structures within 100 m (328 ft) of two separate blasting sites in central-east Ontario. In the interest of both convenience and specificity, I have attempted to organize the paper as a crossdiscipline survey of the field according to the conference’s list of suggested topics. In the paper’s first section, I will discuss the topic of Environmental Improvement and Remediation by using a case study in which not one, but two dead cats were found during the course of a routine pre-blast survey. The second section will undertake a discussion of on-site blaster gossip as an entry point into a wider discussion of Workplace Communications Management. In the paper’s final section, I will detail an early morning encounter with a 300 lb, stark-naked trailer park inhabitant as a cross-sectional analysis of the topics of Drilling in Hostile Environments, Vibration and Seismology (Sizemology?), Ethics in Blasting, Crisis Management, Risk Assessment and Public Relations. It is my hope that this paper will begin to open up a critical space for discussion of the formative experiences of engineering students during the undergraduate university program in terms of their far-reaching effects on later performance within the industry.

Jan 1, 2009

By Scott King, Norm Patterson, Ruilin Yang

The multiple blasthole fragmentation (MBF) model developed by Orica models the contributions from multiple blastholes to fragmentation at any given point in the rock and simulates a production blast with the actual geometry of the blasted overburden and free faces, explosive loading, multiple decking, and delay timing of each explosive charge. The model has been successfully applied to several open pit mines and quarries around the world, including Canada and the United States. The peak particle velocity (PPV) induced in the rock from the explosive detonation is used in the MBF model as the key parameter relating to the size distribution of the rock fragmentation. Relating the PPV to the rock fragmentation is based on earlier work relating the particle velocity to the dynamic strain in rock. A recent publication further revealed that the PPV is related to the maximum relative displacement that induces three dimensional strain at a point in the rock. The model can explicitly model most of the blast design parameters including explosive properties.

Jan 1, 2018

By Brent Blanchard

As most veterans of our industry are aware, explosive demolition by its very nature is often a challenging proposition. Even under the best of circumstances, proper planning and care must be taken during a variety of processes to ensure a safe, successful result. However, every now and then a project suddenly arises where safety, timing and cost factors combine to form a critical scenario requiring rapid execution in an environment far more challenging than the norm. On these occasions, the stresses, complications - and most notably the dangers - related to the industry increase exponentially, and conspire to test the mettle of even the most seasoned experts.

Jan 1, 2003

By Thierry Bernard, Philippe Dozohne

May 13th, in the back country of Nice @arice) collapsed a complete piece of mountain, cutting the RN 2085 and destroying a part of Valabfre’s viaduct. The fist inspections of the site showed that materials had broken loose from surrounding cliffs, The geologists discovered that a block of several thousands of m3 remained suspended in cliff and that it presented a risk raised of gliding. Decision to destroy it by blasting in one blast was there taken by the French department’s council of the Maritime Alps. A race against the clock engaged. Indeed, the RN on 2085 is the main axis connecting the village of Saint Etienne de Tinee and the resort station of ISOLA in the centre of Nice

Jan 1, 2001

By Tristan Worsey, Nathan Rouse, Daykin Schnell

The authors were retained by a proposed underground metals mine operation to evaluate the potential blast vibration amplitudes that could be generated at surface structures above the proposed mine. Literature reviews of published blasting documentation gave little information, data, or models on surface blast vibrations produced by underground mines. At the client’s request, the authors contacted a number of underground mining operations to evaluate interest in sharing blast vibration data with the authors so that the authors could develop an underground-to-surface blast vibration regression equation.

Feb 1, 2020

By Terry Matts, Bruce Ripley, Clark Fletcher, Paul Rapp, Stan Holtby, Jim Dent

The Stave Falls Project of BC Hydro, situated 65km east of Vancouver, BC, Canada, involved the construction of a new two-unit 9OMW hydro-electric facility to replace an existing powerhouse. The final phase of the intake excavation consisted of a plug blast to break the channel through into Stave Lake. The plug consisted of a rock and till wall topped with a fill cofferdam, about 51m wide and between 8 and 12m high. Total rock volume was approximately 2600m3, overlaid with about 4600m3 of till/fill. This paper describes the methodology and practical techniques used in planning and loading the blast, and the precautions taken to protect the new and existing structures and equipment. Blasting of the plug by the normal method using downholes would have required the placing of extra fill and much drilling through casing, so the contractor made the decision to drill horizontal holes from the dry, downstream side. Because of poor rock conditions, all 183 holes had to be drilled oversize at 3.5” dia. and fitted with 2.5” id. plastic pipes to keep them open. Hole lengths ranged from 2.5 to 18rn, with a pattern of 1.5m spacing and l.Om burden (with the holes slightly fanned vertically). Because of significant water exposure, a film-packaged emulsion explosive was used, placed using a pneumatic cartridge loader for maximum borehole compaction. The powder factor averaged 1.3kg/m3 (2.21bs/yd3, rock only). An initiation system of combination surface/downhole delay shocktube units was employed, with double and triple redundancy. The maximum number of holes firing in any 8ms window was limited to three (to minimize vibration), while the whole sequence was fully activated before the first hole fired. All shocktube connections were secured and covered over at the foot of the rockface before flooding the excavation downstream of the plug prior to the shot, To protect the powerhouse gates from hydraulic shock, all hole collars were grouted and an air curtain was provided. The blast was completely successful. A maximum vertical displacement of 6m was recorded, but no flyrock was evident. Readings for peak over-pressure and vibration were well below the allowed limits. Mucking proved to be easy, with fine fragmentation, full pull, and no tights.

Jan 1, 2000

By Reinhold Daykin, Piers Wendlandt, Nathan Rouse

Drilling and blasting are key components of every hard-rock (i.e., metal/nonmetal/coal) mining operation. Well-executed and maintained drilling and blasting can have a major positive impact on the overall success of such operations. This case study presents the implementation of a new drill and blast engineer position and systematic improvement of the drill and blast operations at a surface metal mine.

Feb 1, 2020

By Tony Rorke, Tamara Wiseman

Due to the advancements in technology it becomes easier to obtain accurate measurements for mining, quarry, and construction operations even in the most remote places. The use of off-the-shelf photogrammetric imaging technology and unmanned aerial vehicles (UAVs) are becoming more common in the mining industry for blast design and surveying. Pattern optimization, face profiles, pre and post blast volumetric, stockpile measurements and mine mapping are all areas where these technologies can be used with ease.

Jan 1, 2015

By Sedat Esen

"This paper presents a critical review of the fragmentation data obtained from some large open pit copper and gold mines. Database ncludes 35 mines with Uniaxial Compressive Strength values ranging from 19 MPa to 227 MPa (2756 psi to 32923 psi). Variation in the fragmentation data and the causes are discussed in detail. Quality assurance/quality control (QA/QC) in drilling and blasting was shown to have significant impact on fragmentation. In addition, controllable blast design parameters including drill pattern, powder factor, blast timing, stemming length, etc as well as the large blast sizes havesignificant potential to improve fragmentation. Feed size requirements of crushing and grinding circuits were discussed in detail. The paper discusses the effects of different size fractions (top size, 80 %passing size and % passing 10 mm (0.5 in)) on the downstream processes and the role of the fragmentation model in the mine to mill process. Blast domains based on rock strength and structure canbe established by using a fragmentation model which is calibrated using measured fragmentation data. This allows the blast engineer to compensate for changing rock characteristics and stabilize the ROMfragmentation size and result in increased crusher and mill throughput. Two case studies were presented to demonstrate the benefits achieved in downstream processes. Main benefits were reduced downtime at crusher circuits, improved mill throughput as well as reduced total operating cost. A simple relationbetween uniaxial compressive strength and powder factor was proposed using the database for the optimized mines as a guideline to allow site engineers to compare their sites against the other sites."

Jan 1, 2017