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By Edward L. Mooney

The past 15 years has .seen a dramatic increase in the use of computers in the mining industry. Sanford (1) has provided a comprehensive listing of available programs by application within the mining industry as a whole. Figure 1 below illustrates some of the primary uses and computer techniques currently in application in surface coal mines. As shown in Figure 1, computers have been applied to virtually every facet of surface mine development and operation. In particular, many programs presently exist to significantly reduce the time and effort required during the, planning and design phase of a surface mine. Close examination of the approach taken to utilize existing programs, however, reveals that in most instances applications have been implemented piecemeal with the result that users must be fairly sophisticated in their knowledge of computer applications.

Jan 1, 1979

By Tilley H. L

The 90 m deep Yallourn Open Cut brown coal mine in the Latrobe Valley, Victoria is developing into an area close to a reverse fault. A major batter stabilisation program, matched to ongoing operations, has com- menced to maximise coal recovery where the fault is within 100 m of the Open Cut. The various mine development options considered during the planning stages are outlined. These options were formulated in a back- ground of geotechnical constraints and the need to maintain continuous and reliable coal supply at a time when a new coal field would be developed. The geotechnical investigations and analysis procedures under- taken to determine stability of the batters during their excavation are presented. The geotechnical constraints on the mine design and opera- tions required to ensure safe working conditions are detailed. Current operational and batter stability conditions are considered satisfactory.

Jan 1, 1989

By Newman H. A

Goldsworthy Mining Limited is currently mining iron ore at an annual rate of 7 million tons from several small orebodies, each of which exhibit wide variations in iron, phosphorus, silica and alumina contents. Each orebody is mined at its average ore reserve grade and therefore mine planning and grade control techniques have had to be tailored to achieve a constant production blend.

Jan 1, 1973

By Pabel Alvarado

Mineral deposits with large data uses different block dimensions in Long term planning (LTP), short term planning (STP), and ore control (OC). Using applications can Re-block, Krige, Compute variable, Compute Route, etc. necessary block models with multiple dimensions can be created. For instance, disseminated deposits require granular ore control block model because mineralization can be unpredictable. Then different block size must be created for the ore control activity and different block size must be shaped individually in LTP, STP, and OC.

Sep 1, 2017

The Telfer main dome open pit is operated by Newcrest Mining Limited at a current production rate of 50 Mt/a from a pit dimension compromising 2 km strike length, 1 km width and 250 m depth. As part of the refeasibility of the Telfer operation undertaken early this decade, Newcrest identified that an underground sublevel cave (SLC) operation along with an increased scale of open pit would support a new plant targeting the processing of gold and copper ore at 17 Mt/a rates. The SLC was initiated in late 2006 and broke into the open pit in late 2009. This situation is unique across the mining industry where a cave breakthrough was planned and occurred within an active large open pit operation. The SLC broke though into the west side of the Main Dome open pit into a specially prepared bench that was left at the 5384 RL of cut-back stage 3. A main haulage ramp is within 100 m from the edge of the cave breakthrough zone and this ramp passes down to the active levels which are progressing toward the 5200 RL. This paper presents insight into the mine planning and risk management associated with continued operation of the open pit operation while an active SLC breaks through. The cave breakthrough presents unique areas for risk management as there is potential for rapid propagation and subsidence. To support the undertaking, mine design and major hazard management planning has been carried out. Focus areas include; dual ramp system design, preloading the breakthrough area, monitoring of cave propagation and air gap using a seismic system and deep hole extensometers, wall stability and subsidence monitoring using radar and prism systems, and key trigger and response planning.

May 1, 2010

Ranger Uranium Mines (RUM) operates an open cut located in the Top End of the North- ern Territory. Strict environmental controls govern all operations and the water management requirements have the greatest impact on mine planning. The two main goals of planning are to provide mill feed and to mine sufficient suitable quality waste rock for ongoing con- struction of the tailings dam. Early planning concentrated on staged development of the pit to provide access to as much ore as possible for a given amount of development. All waste was considered to be suitable construction material. Grade control of crusher feed was the main problem in planning, as wide vari- ations occur in ore grade over relatively short distances. Water management for the site ope- rates a no release' system for contaminated waters. Design storage has proven inadequate, and the open cut has been used as the extra storage. As construction of future stages of the tailings dam requires non-mineralised rock materials which meet specific quality criteria, the mine has had to re-examine long term plan- ning and pit development strategies. This has entailed the collection of much data not re- quired under normal mining conditions, such as the assaying of waste drill core. The overall impact on mine planning of the environmental regulations has been to alter the philosophy of earlier planning, making it necessary to create a new strategy for pit development with

Jan 1, 1984

The process of mine planning at AnacondaÆs nickel and cobalt laterite operation located at Murrin-Murrin in the Northern Goldfields of Western Australia is carried out in a number of stages in an endeavour to determine the optimum mining sequence in order to maintain supply to the 4 Mtpa plant subject to operational constraints. The 296 Mt @ 0.99 per cent Ni and 0.064 per cent Co ore reserve (based on a cut-off grade of 0.8 per cent Nickel) is spread geographically widely over three regions comprising Murrin North (15 km + 15 km), Murrin South (7 km + 16 km) and Murrin East (5 km + 13 km) (refer Figure 2). The nickel mineralisation has been broken up further within each region into 18 separate manageable block models representing the 32 different deposits. The models are based initially on the 50 m + 50 m resource drilling for long term planning and updated with 12.5 m + 12.5 m grade control drilling prior to mining. Each of the individual block models are optimised using Whittle 4X software to provide the shells used as the basis for each of the 126 pit designs. The pits are generally nested with starter pits targeting the higher value shells with subsequent pits incrementally cutting back ultimately to the life of mine shells. A series of steps including: the coding of the individual pits into the block model; data export; TCL scripting (to calculate additional economic and tracking information); importing; and re-blocking; completes the transfer of the data into a MineMax (mixed integer linear programming schedule optimising software) model. Using MineMax and the application of operational and production constraints allows the optimisation, assessment and economic evaluation of alternative scenarios in order to determine the optimum life of mine plan and schedule.

Jan 1, 2003

By S. P. Winkelmann

The expansion in gold production in the Carlin 'Trend over the last few years has been one of staggering proportion. To increase gold production while minimizing capital requirements and providing for the safe and efficient mining and processing of ores has required a tremendous effort by the Mine Engineering group at Newmont Gold. This paper discusses the organizational changes implemented to effectively deal with a full range of engineering problems and how the Newmont Gold Mine Engineering group dealt with these problems. Specially developed computer software and their applications will be explained. Improvements in the techniques used in converting geologic resources into reserves, and in scheduling the mining of multiple pits to feed multiple processing facilities, as well as ore control procedures are presented. Current mine engineering practices are discussed.

Jan 1, 1990

By Steven Hoerger

Newmont Mining has a large, integrated gold-mining operation in northern Nevada with several mines, stockpiles and processing facilities. There are more than 90 defined metallurgical ore types and more than 60 defined gold-recovery process options. Newmont developed a mine plan and process model to take better advantage of the available synergies at its Nevada mines. This plan includes a mixed integer and linear programming optimization tool. This system is maintained and operated by a Nevada planning group. Standard in-house planning software tools and methods have been implemented at all mine sites. These changes have allowed a reduction in mine engineering staff and have increased the effectiveness of mine planning.

Jan 1, 1999

By Stephen J. Brower

Located in Central Nevada, The Round Mountain Gold deposit has been continuously mined since 1977. Present proven and probable reserves are 226 Mt (250 million short tons) at 1.1 g/t (.032 oz per short ton). The current open pit mining rate of 118 Kt (130,000 short tons) per day is producing 41 Kt (45,000 short tons) per day of ore to be processed by heap leach methods. At this rate, the current reserves provide a 16 year mine life. The high mining rate and strict ore delivery requirements mandate comprehensive and realistic mine planning. The mine planning process is described in three general steps: Deposit Modeling; Mine Design; and, Production Coordination and Support.

Jan 1, 1989

The Electricity Generating Authority of Thailand own and operate an opencut mine supplying coal to on-site power stations at Mae Moh, 600 km North of Bangkok. The mine is being expanded from an annual production of 1.5 million tonnes per year in 1982 to over 9.5 million tonnes per year by 1991. The mine will be amongst the largest open pit operations in the world. It is technically difficult to operate and plan due to complex geology, weak strata and surface constraints including reservoirs, forests and traditional villages. This paper presents a case study of mine planning for the above project including associated collection and processing of geological and geotechnical information. The existing operation is described, as well as the strategy adopted for the mine at expanded production. The planning covers various phases of mine planning including a Conceptual Study, a Definitive Study and detailed short term planning. Each stage incorporated new information and reflected a higher level of confidence in the data and resulting plan. Sophisticated computer techniques were required including geological modelling, calculation of volumes, geotechnical analysis, scheduling and costing. The planning was undertaken on site by a team of Australian and Thai Engineers as part of the Thailand-Australia Lignite Mines Development Project which is a four year programme of assistance funded by the Australian Government.

Jan 1, 1986

By M. G. Premo

The McKinley Mine is located in the northwest New Mexico, in McKinley County, approximately 25 miles from Gallup. The mine is operated by The Pittsburg & Midway Coal Mining Co. (P&M), a wholly owned subsidiary of the Chevron Corporation. P&M is headquartered in Englewood, Colorado. Since the McKinley Mine began operations in 1962 a total of 83,391,000 metric tons of coal have been sold through 1990. The 1991 production was approximately 5.000.000 metric tons. The mine operations are contained on a 109.000 square kilometers lease area of which 44.000 square kilometers are on the Navajo Nation. The present customer base consists of four utilities and one industrial account, all of which are located in Arizona. The utility customers are the Arizona Public Service Co. Cholla Station at Joseph City, The Salt River Project. Coronado Generating Station near Joseph City, and The Tucson Electric Company, Irvington Generating Station in Tucson. The industrial customer is the Stone Container Corporation, Snowflake Paper Mill.

Jan 1, 1992

By B Ascott, J Kennedy, A White

At mines with low tonnes per vertical metre, like the Jundee Mine in Western Australia, operated by Newmont Asia Pacific, high development rates across multiple mining areas are critical to achieving the delivery outlined, or promised, in the annual business plan. The challenge is to deliver the short-term requirements while keeping in balance with the long-term strategic direction. Newmont Jundee has developed a system called æMine Planning by QuartersÆ that integrates the planning process with the business process in one end-to-end continuum. Short-, medium- and long-term schedules are reviewed and updated by applying four integrated subprocesses, which capture new information as it becomes available. The four subprocesses are: resource development planning û evaluating mineral resource,reserve development planning û preliminary design for new reserves,mine operating planning û final mine design for reserves, andmine production planning û detailed plans for stoping a proved reserve. Commercial mine planning software is used in these subprocesses to facilitate the flow of information into a central storage æhubÆ for uploading into the rolling business plan. A regular and consistent quarterly review helps to identify and qualify areas of business risk at an early stage, allowing time to plan for contingency and minimise the impact of the risk.

Jan 1, 2008

By James E. Lonergan

To determine the best materials handling system for surface mined materials, one must develop a mine plan for each candidate system based on the most efficient use of that system. This is essential for a fair, unbiased economic compari¬son of the candidate systems. This paper will present two case studies where an integrated mine planning /systems engineering approach has been utilized at different levels of detail in the analysis of an in-pit crushing/conveying system vs. total truck haulage at 2 open-pit copper mines.

Jan 1, 1985

By Alan D. Curtis

A standard planning block model for Phelps Dodge North America Operations has been developed to improve mine planning efficiency and performance in a skill starved environment. The model saves time on software management and training, consolidates data and standard information/output, enhances evaluation and strategic process, and improves communication between sites.

May 1, 2007

By Westcott PC

The development of a coal project must pass through a number of phases, taking it from a preliminary evaluation through to detailed mine planning. For each phase the cost of data acquisition and associated mining studies increases exponentially for linear improvement in confidence levels. Within each mine planning phase there are four main activities. These are the economic ordering of reserves, the development of optimum mining strategies, mine design and scheduling and finally the estimation and analysis of costs. The development of the optimum mining strategy is one of the most critical aspects of a mining evaluation and the application of economic criteria at this stage of the project is vital to the successful generation of an optimised mine design. A recommended method is the concept of Economic Ratio (ER) which expresses the likely cost of mining from a given location in a deposit in terms of the value of the product likely to be recovered. The most economic mining strategy will be to mine areas from low economic ratio to high economic ratio within the constraints of reasonable equipment application. When selecting equipment a particular machine should not be selected solely on comparison with other machines in isolation, but the total application must be analysed. In the final selection the decision should be based on whether or not it has a beneficial effect on overall project economics. The economic assessment must take into account the time value of money, so the real cost can be determined with adequate provision for capital and operating costs over different time spans.

Jan 1, 1983

To provide a means for rapidly evaluating proposed mine layouts in order to avoid potential hazards while minimizing loss of coal. The Approach: Development of a computer program that will compute many possible mine layouts by changing the mine plan until the arrangement giving minimal hazards with optimum extraction is found. How It Works: The Hazard Evasion Program for Mine Planning, developed by the Bureau's Denver (Colo.) Mining Research Center, tests hundreds of possible solutions to a mining layout, and by sorting out the 10 best (based on the criteria of maximum safety for workers with minimum abandoned coal), limits the number of choices that need to be considered and appraised for applicability to a given mine scheme. The program is applicable for room and pillar or longwall mining, for oil and gas well hazards, and for other hazards that can be described mathematically such as channel sands, potential bad roof areas, faulting, voids, or water pockets.

Jan 1, 1974

By Thomas L. Vandergrift

Multiple-scam mining is becoming more common in the United States, especially in the East, where primary reserves arc being depleted, forcing mining companies to develop secondary seams, Although mine engineers and planners are aware of the basic effects of seam interaction and generally follow guidelines for columnizing entries and avoiding load abutments, mine design earn greatly benefit bum more quantitative estimates of scam interaction effects. This paper presents case studies from two eastern mines subject to seam interaction effects where pre-mining stresses were quantified: the Mingo Logan Coal Company's Mountaineer Alma A Mine, and Peabody Group's Lightfoot No. 2 Mine. In each of these mines. mining is being carried out within 60 to 90 ft of overlying longwall and pillar panels under maximum cover of about 1,100 ft As part of overall mine planning and design efforts al these mines. NSA Engineering performed numerical modeling analyses using the non-linear boundary-element code MULSIM/NL Input parameters were calibrated by modeling areas where ground conditions resulting from seam interaction were well documented. By incorporating actual cover loading based on topography and seam dip, and the integrity of remnant, gate road, arid harrier pillars in the overlying mines, the pre-mining vertical stress in the underlying scants was estimated based on the pre-mining stress, plans for mains, gate road, bleeder, and pillar panels were developed. Although mining experience in these areas has beers somewhat limited to date, she designs developed as a result of these analyses have so far proven successful.

Jan 1, 2000

By Milton C. Head, Aulton E. Roland, William E. Hawes

INTRODUCTION Uranium mining in the Grants Mineral Belt has undergone changes from methods pioneered during the 1950's and has now become fairly standardized throughout the district. The orebodies vary in size and shape and have been most successfully mined by using modified room and pillar methods with pillar recovery. This paper will expand on methods and equipment that are being used and modifications of these that will increase productivity and efficiency. GEOLOGICAL BACKGROUND The petrology of the Grants Mineral Belt consists of alternating layers of sandstone and shales (mudstone), with occasional thin layers of coal. The sandstones are aquifers which are generally artesian to some extent. The shales are bentonitic and decompose into extremely sloppy mud when exposed to water. Figure 1 shows a typical geologic section. Most of the uranium produced in the Grants Mineral Belt comes from the Westwater Canyon member of the Morrison Formation and occurs as scattered ore bodies throughout the formation. This formation consists of layers of bentonitic shale and sandstone of varying degrees' of cementing and grain size. It is also a very significant artesian aquifer. The unconfined compressive strength of the various formations is not high, as shown in Table I. It is important to note that these represent average values and a great range may exist within a single formation, especially In the Westwater which is the ore formation. [ ]

Jan 1, 1982

By John G. Henning

Unplanned ore dilution has a direct and large influence on the cost of a stope, and ultimately on the profitability of a mining operation. This paper presents results of a study on the influence of a variety of factors on ore dilution in a blasthole stoping environment. A series of 3-D numerical models were developed and analyzed to examine the effect of mining depth, stope geometry and stope setting within the orezone extraction sequence. To quantify modelled ore dilution from the three-dimensional simulations, the ore Dilution Density (DD) is a term introduced in this study to denote potential hanging-wall overbreak. It was found that hanging-wall overbreak is not significantly influenced by depth alone, and that stopes with large or small axial ratios are more stable than large rectangular stopes. It was also demonstrated that, in addition to stope dimension, the amount of unplanned dilution differed according to stope type. Five stope types were identified, based on their position within a tabular blasthole mining sequence. The methodology presented in this paper can be adopted to develop mine-specific design tools for the estimation of ore dilution associated with a proposed mine design. This can prove extremely helpful in the process of underground mine planning and optimization.

May 1, 2007