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By Raymond W. Henn

The 32nd annual short course ?Grouting Fundamentals and Current Practice? was held at the Colorado School of Mines, June 13-17, 2011. The field demonstration portion of the course was conducted June 16 at Baski Inc.?s yard in Denver, CO. The full-scale field demonstration presents many types of drilling and grouting equipment in operation as well as numerous grouting methods per-formed under various field conditions. As part of the field demonstration, the class was shown the proportioning, mixing, testing and injection of various cement grout mixes into sand columns under controlled and recorded conditions. These sand column demonstrations have been conducted under controlled and measured conditions each year since 1999 as part of the short course. The sand column demonstrations were conducted prior to 1999, but with less quality control and minimal record keeping of the proportioning, mixing, testing, injection pressures and the final permeation results.

Jan 1, 2011

By A. T. Iannacchione

From 1990 to 1996, 16 states reported 92 injuries from falls of roof, rib or face in the more than 90 underground stone mines in the United States (Fig.1). Missouri, Pennsylvania and Kentucky accounted for 48% of the total number of injuries (Fig. 2). Of this total, 11 miners were killed. Of the 11 fatalities, 10, or 91%, were associated with unrecognized loose or failed rock within the roof beam. Additionally, unrecognized roof beam failures resulted in a majority of the falls of ground injuries occurring in underground US stone mines from1990 to 1996. This number is not large in magnitude. But a workforce of fewer than 2,000 miners makes for a high fatal-accident rate. The severity of the typical fall-of-ground injury is, in general, very high. About three-fifths of all roof, face and rib fall injuries were designated by the US Mine Safety and Health Administration (MSHA) as some kind of lost time accident. MSHA assigns each accident a severity value from one to six. A one represents a fatality, a two, a permanent disability and three, a lost time accident (Fig. 3).

Jan 1, 2000

All aspects of precious metals processing were featured at a symposium held Oct. 3-6, 2007, at Loews Ventana Canyon Resort in Tucson, AZ. Although billed as "Precious Metals Processing: Advances in Primary and Secondary Operations," the symposium also looked at economic, regulatory and environmental issues affecting the precious metals industry. The symposium was sponsored by SME; The Minerals, Metals & Materials Society (TMS); and the International Precious Metals Institute (IPMI). It included workshops, technical presentations, guest speakers and social activities. Mining industry management, process engineers, equipment manufacturers, consultants, metals marketers, academics and others involved in the precious metals industry attended the conference. Needless to say, with gold nearing $25.721g ($800/oz) and platinum pushing $41.801g ($1,300/oz) at the time of the meeting, the mood among the attendees could not have been more positive. The symposium was privileged to have Father Ernest S. Sweeney, professor of Latin American History at Loyola Marymount University, as a guest speaker. Sweeney, a Jesuit priest, provided a colorful account of the history of mining in Arizona and the surrounding region of North America (Fig. 1). He described the importance of the mining industry and said, "To go down into the bowels of the earth to extract its riches for the benefit of all of us is an awesome task deserving our sincere respect and gratitude." However, he warned the industry that: "The ever increasing de¬mands on the mining community for the protection of the environment calls for endless efforts to maintain ethical standards in a business filled with risk, uncertainty and frustrations." Sweeney noted that the Spanish conquest of the Americas was driven by the three fundamental motives of "God, glory and gold." He noted that gold was the basic, most powerful driving force of the conquest and occupation of the Spanish empire. The first European to explore Arizona was the Franciscan missionary Marcos de Niza. He came to Arizona in 1539 in search of the fabled Seven Golden Cities of Cíbola. Sweeny noted that Spanish explorers were consumed, as Cortes himself described it, "with a burning fever that only gold could cure." Sweeney told the story of some of these early explorers, including Francisco Vázquez de Coronado who "mounted an expedition in pursuit of gold and rich empires to conquer." Coronado passed through Arizona and discovered the Grand Canyon. "Coronado returned to Mexico exhausted, bankrupt and disillusioned, but with a wealth of new knowledge of the borderlands of the Spanish empire," said Sweeney. He then described the colorful history of early gold, silver and copper exploration and mining in Arizona, including the famous tale of the Lost Dutchman's Mine. In a luncheon address, David Kanagy, SME's executive director, introduced the attendees to the upcoming OneMine. org Web site. Kanagy told the audience" One-Mine.org will be a collaborative digital library that will

Jan 1, 2008

By William R. Bond, Jim V. Rouse

Introduction The pressure/vacuum (p/v) lysimeter or soil water sampler has become useful for monitoring vadose zone or unsaturated zone water conditions. The soil water sampler was first introduced around 1961. It was used as a monitoring and research device for studies in agriculture and soil contamination around landfills. Since then, it has been used for many purposes. The use of p/v lysimeters at mining facilities to monitor for solution loss is a relatively new idea. The primary purpose of the lysimeter here is to function as an early warning system. It detects leakage through liners of tailings ponds, heap leach pads, and leachate holding ponds. Their use has proven valuable for collecting baseline data and detecting loss of precious leachate fluid. Different lysimeter designs are capable of vadose moisture sampling from near the surface and down to 90 m (300 ft). They are also capable of sampling soil moisture or saturation plume contaminants from areas not accessible by conventional water well installations. The most common installations are usually simple and cost-effective. In many cases, they can be installed without the use of heavy drilling equipment. A properly placed and installed lysimeter can detect solution leaks in several days or weeks. A conventional perimeter monitor well may take months or years to detect a leak of the same magnitude. A discussion on the general design and installation of p/v lysimeters will give an understanding of its versatility. Three case studies of lysimeter installations at mining sites will be examined in detail. Design, Installation, and Sampling Design The basic design of a p/v lysimeter chamber consists of a porous material through which the soil is drawn into a collection chamber. Access tubes run from the unit to the sample station at the ground surface. Most units currently available range from 25 to 76 mm-diam (1 to 3 in.-diam). The sample collection chamber, or body, can vary from 0.6 to 1.8 m (2 to 6 ft) in length. The body can be constructed of PVC casing or Teflon, depending on the installation desired. The collection chamber functions as a holding reservoir for the collected soil moisture. The intake, or porous material, on the lysimeter is the most complex and vulnerable portion of the unit. The pore size selection varies based on the needs of the installation, type of fluid to be sampled, and type of soil material surrounding the unit. Teflon (PTFE) and porous ceramic are used in fabrication of the porous inlet portion. When using a Teflon material, which is hydrophobic, a larger pore size of 70 µm is needed to overcome surface tension and draw water into the collection chamber. It is typically used at sites involving organic contamination, because of its inert properties. Ceramic material is generally hydrophilic, having less surface tension. Therefore, it has a smaller porosity range to conduct the moisture through the porous medium while under vacuum. Pore sizes may be selected from 0.16 to 6 µm, and can be manufactured for the specific needs of the installation. The final major design component of the p/v lysimeter is the access or sampling tubes. The tubes are usually of 6.3-mm-outside-diam. (0.25-in.-outside-diam). They are made of rigid polyethylene or flexible Tygon with a wall thickness of 1.5 mm (0.06 in.). The con-

Jan 4, 1985

By Thomas Sisley, Jozef Zurawski, Richard Switalski

Hilltop Interceptor Contract G is one of the segments of the wastewater control system in the greater Cleveland area. The tunnel is a relief interceptor constructed by the Northeast Ohio Regional Sewer District to minimize combined sewer overflows in the Easterly Service Area. The design study identified the need for a 3.35 m (132 in) diameter, 3.35 km (11,000 ft)in-line storage conveyance tunnel to be constructed at depths of 30 to 70 m (100 to 230 ft).Six structures for access, future flow drop, work shafts and overflow control were required to complete the system. The interceptor reduced the design peak flow from 12.5 m3/s(285 mgd) to 6.1 m3/s (140 mgd) by detaining in line 22,800 m3 (six million gallons) of wastewater.

Jan 1, 1997

The title of “the world’s biggest volume-produced hydraulic breaker,” that was held for more than a decade by the Atlas HB 7,000, changed hands with the launch of Atlas Copco’s HB 10,000 at bauma 2007. A service weight of 10 t (11 st) and up to 50 percent higher productivity represent major steps toward a new market segment: the use of hydraulic breakers as cost-efficient production machines for primary breaking and as a true alternative to drilling and blasting. The HB 10,000 has all the technical features developed by Atlas Copco for its hydraulic breakers and includes: StartSelect — the breaker’s start-up and shut-down behavior can be adapted to the conditions. AutoControl that ensures an optimized balance of impact energy and impact frequency to maximize percussive performance. Auto-Control also reduces blank firing force and controls energy recovery. PowerAdapt — if oil pressure is too high, the breaker shuts down automatically. This prevents downtime and is particularly useful when breakers are used on different carriers. DustProtector II — a combination of multiple strippers prevents abrasive rock dust and foreign bodies from penetrating the lower breaker section. Conti- Lube II — the automatic lubrication unit guarantees optimal lubrication of the breaker at all times.

Jan 1, 2007

By William R. Yernberg

SME’s Arizona Conference was held at the Doubletree Hotel at Reid Park in Tucson on Dec. 5and 6, 2004. The annual conference is organized by the Arizona Conference Board of Directors, which represents SME sections in Arizona and adjacent areas. The conference provides an opportunity for individuals and corporations associated with mining in the region to get together each year to discuss the status of the industry. The meeting featured a keynote address and more than30 technical papers. Two years ago, the U.S. copper industry was facing on a run for two years now,” and “both precious metal and base metal prices are going up.” The increases in metal prices were attributed to development in China and other Asian countries. “With a population of 1.6 billion, China has recently created 80 million jobs,” said Silver.

Jan 1, 2005

By R. Washnock, P. James

"INTRODUCTION Abstract Tankhouse iron control through application of new treatment technology to mitigate conventional bleeding losses is considered. Implementation is discussed and the treatment economics explored. A representative case is assessed. Treatment benefits and application drivers for specific scenarios are noted. Background Hydrometallurgical ore processing has become a significant metal extraction/production avenue in recent decades. In copper mining; the focus for this examination, around 25% of global primary copper production and nearly 50% of US production result from various hydrothermal leaching extraction approaches coupled to Solvent Extraction/Electrowinning (SX/EW) metal production. Generally such processing is favored over pyrometallurgical processes for lower ore grades and as such is finding growing use and is expected to remain a key processing route looking forward with average world-wide ore grades falling as known ore reserves become exhausted. Target Problem And Motivation In hydrometallurgical processing the production circuit may be thought of as a chain of interlocked recirculation loops (Figure 1). Leaching dissolves the target metal from the ore along with other ore components which contaminate the Pregnant Leach Solution (PLS). Iron is a common component in copper ores and, as a result, occurs fairly ubiquitously in copper Pregnant Leach Solutions (PLS) generated by leaching. Leached components migrate through the production circuit from left to right (Figure 1) through a net combination of chemical and mechanical transport mechanisms. Selectivity at the recirculation loop interfaces tends to retard rejected component migration through the production process. As a result, overall relative contaminant migration fluxes are slower than the target metal (copper) and the contaminants tend to build up relative to copper in the more upstream portions of the processing circuit over time with iron often being a significant contaminant. Further, while copper is continuously removed from the system in appreciable amounts, little contaminant exit occurs and the absolute contaminant amounts and concentrations also increase throughout the EW circuit over time."

Jan 1, 2018

Construction of the Boddington Mine 130 km (81 miles) southeast of Perth, is about 89 percent complete. When the $2.9-billion development is finished, it will be the largest gold mine in Australia, producing 31 t/a (1 million oz/year), according to project majority owner Newmont Mining. Newmont?s acting regional group executive for Asia Pacific, Philip Stephenson, told a gold conference in Australia that the project would be ?the biggest thing for Newmont this year.? The project has been in the works for more than 10 years, but because of a three-sided ownership and fluctuating gold prices, it struggled to get started. However, Newmont is set to become the full owner of the project and is moving ahead on the low-grade project. ?We are targeting annual production of 31 t/a (1 million oz/year) for each of Boddington?s first five years. When it is in full production, Boddington will be the largest gold mine in Australia,? Stephenson said. ?The mine?s costs applicable to sales will be around US$9.64/g (US$300/oz) and that puts Boddington into the bottom quartile of the global cost curve. ?Strategically for Newmont, Boddington coming on-line will improve Newmont?s overall global geopolitical risk profile as it delivers greater exposure to an AAA-rated country.? Boddington has a projected mine life of 20 plus years. It has current total reserves of 622 t (20 million oz) and rising. Stephenson said Boddington has the largest reserve base of all gold projects in production or those that are about to go into production in A-rated countries or better. And it will be an important asset for many years to come. Newmont will acquire the remaining 33 percent share held by AngloGold Ashanti in a deal that should be concluded in the next two months. Australian miner Newcrest Mining Ltd. had exited the joint venture several years ago. Newmont had come into the project through the take-over of then Australia?s leading gold miner Normandy Mining, while AngloGold Ashanti gained entry through

Jan 1, 2009

The 112th Annual National Western Mining Conference (NWMC) hosted by the Colorado Mining Association (CMA) drew some political heavyweights, if by voice only, into the fray of two of the hottest topics that the mining industry is currently facing ? climate change and the new energy economy. A changing political landscape in Colorado, as well as in Washington D.C., has given rise to questions about the economic future of the United States and the mining industry?s role in that future. While there has been a recent push away from traditional energy sources to a ?new energy economy? that is rich in renewable energy sources such as wind and solar, the NWMC?s agenda emphasized the role that minerals will play in new energy technologies. The conference was also full of talks about the industry?s role in reducing the United States? reliance on foreign oil and other mineral commodities. To that end, an impressive lineup of speakers were invited to attend the three-day conference Feb. 8-11, in Denver, CO. Unfortunately, Mother Nature had other plans and three of the four headliners, including Denver?s mayor and Democratic candidate for governor of Colorado, John Hickenlooper, were unable to get to the conference because of a massive blizzard on the East Coast locked them in Washington, D.C. However, with modern technology, a full auditorium heard presentations from Hickenlooper, National Mining Association (NMA) president and chief executive officer Hal Quinn and Glenn Kelly, vice president, government affairs for NMA. Republican candidate for governor of Colorado, Scott McInnis, did speak to the crowd in person.

Jan 4, 2010

By Stephen A. Orr

Underground mining is a dynamic art and science with a diverse set of design, production, and economic criteria that must be considered before selecting an optimal method to extract the ore. While all methods can be technically classified as either self-supported, supported, or caving, the multitude of subsystems and existing variations bear witness to the fact that each orebody is unique and, as such, justifies an individual approach to optimize mineral extraction. In this sense, underground mining is an art. The ability to evaluate the unique characteristics of each ore body and utilize sound engineering principles to design the optimal system constitutes effective method selection. The task by no means ends at this juncture, however. Subsequent implementation requires an ability for modification. Very rarely are all the facts available to make a concrete decision prior to development of the resource. As a result, the risk of a wrong decision can never be eliminated. This requires a significant degree of flexibility with each method. Each unit of exploration, development, or exploitation work contributed to a deposit enhances knowledge of the ore body. The best mining methods are those that correctly account for the known parameters but provide an allowance for change at minimal cost and adapt to unanticipated conditions.

Jan 1, 2008

By William R. Yernberg

A conference on coalbed and coal mine methane was held March 27 and 28, 2000, in Denver, CO. The conference, organized by the Strategic Resource Institute, was attended by leaders in the coal mining and gas energy industry. The conference focused on the recovery of methane from coal beds as an energy resource and the removal and utilization of coal-mine methane (CMM) related to underground coal mining. The two-day conference discussed methane resources around the world, methods of recovery, methane markets, underground coal mining, health and safety issues and environmental issues related to methane. The consensus among the presenters is that the future looks promising for coal bed methane (CBM) and CMM.

Jan 1, 2000

By R. L. Hudak, R. F. Randolph, A. S. Azman

The mining workforce experiences high rates of hazardous noise exposure and hearing loss. However, previous studies have identified specific behavioral and attitudinal barriers that keep miners from effectively acting to prevent their own hearing loss. The National Institute of Occupational Safety and Health (NIOSH) has developed several new hearing loss prevention tools and interventions that specifically target these barriers to prevention. The NIOSH Hearing Loss Simulator addresses motivation to take action and knowledge about the consequences of noise exposure. The QuickFit earplug test device and QuickFitWeb online hearing protection tester address barriers to effective earplug and earmuff use by verifying at least 15 decibels of protection. The NIOSH Roll-Pull-Hold technique helps miners obtain better protection through an easy-to-remember set of steps that improves attenuation by nine decibels. The “Inquiring Ears Want to Know” fact sheet helps miners to understand audiograms and to use them to maintain their hearing health. Each of these interventions can be used within the context of a comprehensive hearing loss prevention program.

Jan 1, 2010

By R. Marrill

Mining is a complex and intensive industry. Extracting raw material with different shapes, sizes, chemistry from the earth?s crust and transform them into a standardized and high quality final product is a big processing challenge - which involves energy and control on large scales. Not only is the physical work challenging, the mining industry today is facing unprecedented challenges: Decline of mineral grade and reserves, cost escalation for new developments and modernization, regulations, safety, lack of skilled people, and market uncertainty are the new constant. It is clear that process control and management of electrical power will be of increasing importance to the recovery rates the mine will achieve. The objective of this paper is to provide a quick vision about future trends and evolutions in technology related to these fields and their impact on Electrical Safety and Control of the mineral recovery. The paper will cover trends in safety, energy management and efficiency, communications of data, control room evolutions, plant integration, other control technologies, and we will examine how these technologies provide information and the benefits of aligned reporting systems to address current industry challenges. More than just the trends or breakthrough concepts, current technologies are available today that can be applied in the mineral recovery operations now to help overcome anticipated future challenges will be presented later in this document. Finally, a brief discussion to look at some real tools to help make real time changes to the process while maximizing recovery and optimizing cost.

Feb 27, 2013

By L. Westerstrom

Supply and Demand After a dismal first half, the industry saw a marked improvement in its markets during the final six months of 1983. Domestic consumption was 17.6% higher in the second half of the year, primarily due to a surge in electric power requirements. The sharp increase in demand for electric power during the third and fourth quarters afforded utilities the opportunity to lower stocks that had accumulated to record levels during 1982. Consumer stocks were reduced from 179 Mt (197 million st) at the end of June to 153 Mt (169 million st) by the end of the year. That is the largest inventory drawdown on record during a six-month period without a major coal strike. Despite the huge depletion in inventories, coal production in the second half of 1983 rose 1.3% above output in the second half of 1982. However, because of the disappointing first half, production in 1983 totaled only 712 Mt (785 million st), 6.4% less than the 760 Mt (838 million st) produced in 1982. Demand The extent to which the economic recovery affected coal markets in 1983 varied: • total domestic coal consumption increased 4.2%; • electric utility coal consumption increased 5.3%; • exports declined by about one-fourth; • coal consumption at coke plants declined 9.5%; and • coal consumption in the other industrial sectors increased 2.9%. Domestic coal consumption totaled 667 Mt (737 million st) it 1983, 27 Mt (30 million st) more than 1982. Electric utility consumption increased from 539 M1 (594 million st) in 1982 to 567 M1 (625 million st) in 1983. Coal consumption at coke plants declined from 37 Mt (41 million st) to 34 M1 (37 million st). Residential and commercial use increased 181 kt (200,000 st) - from 7.4 to 7.6 Mt (8.2 to 8.4 million st). Electric Utilities: Electric power generation increased 3.1% in 1983. Demand for electric power increased in all major consumer categories. Residential and commercial use rose 2.7% and 3.3%, respectively. The most striking increase, however, and indicative of the economy's strong upturn, was the increase in industrial electric power use. Industrial power requirements, which declined 9.8% in 1982, rose 4.1% in 1983. The electric utility sector continued to expand its use of coal last year while lowering its requirements of oil and natural gas. In 1983, electric generation from coal increased 5.7%, while genera-

Jan 5, 1984

By Lee W. Abramson

Performing risk analyses on tunnel projects has become common place and on many projects it is required from an owner or regulatory perspective. After the project is planned, designed and constructed, the data concerning identified risks, assumptions, costs, probabilities and mitigations is generally long forgotten and buried in some file somewhere. A study was performed comparing predicted risks versus actual events on several recently constructed tunnel projects. Probabilities and costs for selectively common risks on tunnel projects have been studied and re-evaluated. Conclusions are presented that can guide future projects and the veracity of the tunnel risk analyses performed.

By J. Drelich, J. Pletka

Lost foam casting patterns are foamed polystyrene shapes glued together into the shape of the part to be cast and are coated with a refractory material consisting of a mineral mixture and binders. Prior to casting, a significant number of the patterns are damaged and inevitably land-filled. In this study, a process is developed for the recovery of foamed polystyrene from the coating and glue contaminants. The process consists of shredding, impact comminution, size classification and density separation. It is successful in separating up to 97% of the contaminants, while recovering 95% of the polystyrene.

Jan 1, 2001

By Vincent Tirolo

The proposed Second Avenue Subway is a new two-track subway line running from 125th Street and Park Avenue at the north, east along 125th Street to Second Avenue and south along Second Avenue to the Financial District in lower Manhattan, NY with 16 new stations and 13.6 km (8.5 miles) of track. The project has been broken into four construction phases. The initial Phase 1 operating segment includes three new stations (96th, 86th and 72nd Street stations) with a connection to the existing Broadway line at the 63rd Street Station at Lexington Avenue. Rehabilitation of the 63rd Street Station is also included in the scope of Phase 1. Subsequent phases extend service north and west to 125th Street (Phase 2), south to Houston Street (Phase 3) and finally to Hanover Square (Phase 4). The DMJM Harris/Arup Joint Venture (DHAJV) prepared the Contract Documents MTA for Phase 1. Parsons Brinckerhoff is providing the MTA with construction inspection services for Contract C-26002. In April 2007, NYCT awarded first Phase 1 for $337 million to S3 Tunnel Constructors, a tri-venture comprised of Skanska USA Civil, Schiavone and Shea. Contract C26002 is for the construction of the tunnel boring ma-chine (TBM) launch box and the mining of the TBM tunnels from 92nd Street to 63rd Street. The major part of the contract is to construct a shaft, commonly referred to as the launch box, from East 92nd Street to East 95th Street having dimensions of 244-m- (800-ft-) long by 18.9-m- (62-ft-) wide and a depth of 19.8 m (65 ft), including more than 91,000 m3 (119,000 cu yd) of soil and rock contained within its walls. The launch box will ultimately become the southern half of the 96th Street Station. The focus here is geological conditions at the launch box and existing structures along the launch box. These geologic conditions and existing structures had a major influence on the selection and design of the support of excavation system (SOE), the SOE bracing system, construction staging, the ground movements, dewatering and other challenges of constructing the launch box (Fig. 1).

Jan 1, 2013

By Ian Hutchison, Ted Sluder, Jack Caldwell, Don Moore

Introduction The Cannon mine at Wenatchee, WA has recently been brought into operation to recover gold from the sandstones of the Swauk formation. The mine is a joint venture between Asamera Minerals (US) Inc. and Breakwater Resources. A tailings impoundment was constructed to impound 2.7 to 3.6 Mt (3 to 4 million st) of tailings at 1.8 kt/a (2000 stpd) over about five years. This paper describes the design and construction of the impoundment. In particular, it describes the 100 m (300 ft) high earthfill embankment that is the main feature of the facility. Project environment The project is located on the outskirts of Wenatchee, a town of about 40,000 people. The town is situated on the flat alluvial terraces beside the Columbia River. The Cascade Mountains rise from the terraces in a series of ridges and valleys. The mine is at the foot of the Cascades. The tailings impoundment is in one of the steep valleys. The climate is mild and dry (Table 1). Site selection Twelve alternative sites within a 16-km (10-mile) radius of the mine were examined. Decision making theory was used to select the most suitable site. Advantages of the chosen site include its proximity to the mine and its low visibility from points of common public access. Also, the area was already heavily impacted by an existing silica quarry. The major disadvantage of the site is the need to pump tailings over a distance of 1.5 km (1 mile) and against a static head of 200 m (655 ft). Also, it is located in a gulch just upstream from the town of Wenatchee. Site geology The impoundment is generally underlain by interbedded sandstones and siltstones. The siltstones are often shattered. The sandstones are often friable. Both rock types are extensively jointed. Some isolated faulting of the sediments occurred before the area was covered with basalt flows. About 10,000 years ago, at the end of the ice age, the basalts were covered by 3 to 10 m (10 to 33 ft) of wind blown loess - a fine sandy clay and silt. River deposits filled the base of the valley to depths between 5 and 25 m (16 and 82 ft). Under the main part of the embankment, these materials were removed to expose bedrock. Ground water flow is generally through the more permeable layers. The permanent water table is about 5 m (16 ft) beneath the ground surface. Project and impoundment layout Figure 1 shows the layout of the mine, the mill, and the tailings impoundment. The tailings deliv-

Jan 8, 1986

By Katherine Hynard, Colin Eustace

Suboptimal decisions introduced during the mine planning process are generally a consequence of both a myopic view of planning objectives as well as time and resources available to convert longer-term plans into execution plans. Erosion of strategic mine plan value in conversion to execution plans is likely to amount to billions of dollars each year. When integrated with operations data feeds, simulation and optimization tools can be used to preserve the value in the strategic mine plan. Optimization models are capable of both automating production of execution plans and improving performance. This reduces the manual burden of revising plans while improving alignment with long-term production objectives. Simulation models can also support the process of developing effective execution plans by providing forward visibility of mine operations performance. They can also be used to test the robustness of optimized execution plans and response to operational variability and disturbances.

May 1, 2025