Mining engineers deal with the exploration, location, and planning for removal of minerals and mineral deposits from the earth. These include metals (iron, copper), nonmetallic minerals (limestone, gypsum), and coal. Mining engineers conduct preliminary surveys of mineral deposits and examine them to ascertain whether they can be extracted efficiently and economically, using either underground or surface mining methods. They plan and design the development of mine shafts and tunnels, devise means of extracting minerals, and select the methods to be used in transporting the minerals to the surface. They supervise all mining operations and are responsible for mine safety. Mining engineers normally specialize in design, research and development, or production. Mining equipment engineers may specialize in design, research, testing, or sales of equipment and services. Mines also require safety engineers. There are approximately 5,200 mining and geological engineers employed in the United States.
Mining Engineer Career History
The development of mining technology stretches back some 50,000 years to the period when people began digging pits and stripping surface cover in search of stone and flint for tools. Between 8000 and 3000 b.c., the search for quality flint led people to sink shafts and drive galleries into limestone deposits.
By about 1300 b.c., the Egyptians and other Near Eastern peoples were mining copper and gold by driving adits (near-horizontal entry tunnels) into hillsides, then sinking inclined shafts from which they drove extensive galleries. They supported the gallery roofs with pillars of uncut ore or wooden props.
Providing adequate ventilation posed a difficult problem in ancient underground mines. Because of the small dimensions of the passageways, air circulated poorly. All methods of ventilating the mines relied on the natural circulation of air by draft and convection. To assist this process, ancient engineers carefully calculated the number, location, and depth of the shafts. At the great Greek mining complex of Laurion, they sank shafts in pairs and drove parallel galleries from them with frequent crosscuts between galleries to assist airflow. Lighting a fire in one shaft caused a downdraft in the other.
Ancient Roman engineers made further advances in the mining techniques of the Greeks and Egyptians. They mined more ambitiously than the Greeks, sometimes exploiting as many as four levels by means of deep connecting shafts. Careful planning enabled them to drive complicated networks of exploratory galleries at various depths. Buckets of rock and ore could be hoisted up the main shaft by means of a windlass. Unlike the Greeks and Egyptians, the Romans often worked mines far below groundwater level. Engineers overcame the danger of flooding to some extent by developing effective, if expensive, drainage methods and machinery. Where terrain allowed, they devised an elaborate system of crosscuts to channel off the water. In addition, they adapted Archimedean screws—originally used for crop irrigation—to drain mine workings. A series of inclined screws, each emptying water into a tub emptied by a screw above it, could raise a considerable amount of water in a short time. It took only one man to rotate each screw, which made it perhaps the most efficient application of labor until engineers discovered the advantage of cutting halls large enough for an animal to rotate the screw. By the first century a.d., the Romans had designed water wheels, which greatly increased the height to which water could be raised in mines.
Mining engineering advanced little from Roman times until the 11th century. From this period on, however, basic mining operations such as drainage, ventilation, and hoisting underwent increasing mechanization. In his book De Re Metallica (1556), the German scholar Georgius Agricola presented a detailed description of the devices and practices mining engineers had developed since ancient times. Drainage pumps in particular grew more and more sophisticated. One pump sucked water from mines by the movement of water-wheel-driven pistons.
As mines went deeper, technological problems required new engineering solutions. During the 18th century, engineers developed cheap, reliable steam-powered pumps to raise water in mines. Steam-powered windlasses also came into use. In the 1800s, engineers invented power drills for making shot holes for rock-breaking explosives. This greatly increased the capability to mine hard rock. In coal mines, revolving-wheel cutters—powered by steam, then by compressed air, then by electricity—relieved miners from the dangerous task of undercutting coal seams by hand. As late as the mid-19th century, ore was still being pushed or hauled through mines by people and animals. After 1900, however, electric locomotives, conveyor belts, and large-capacity rubber-tired vehicles came into wide use so that haulage could keep pace with mechanized ore breaking. The development of large, powerful machines also made possible the removal of vast amounts of material from open-pit mines.
Mining Engineer Job Description
Before the decision is made to mine a newly discovered mineral deposit, mining engineers must go through successive stages of information gathering, evaluation, and planning. As long as they judge the project to be economically viable, they proceed to the next stage. Review and planning for a major mining project may take a decade or longer and may cost many millions of dollars.
First mining engineers try to get a general idea of the deposit’s potential. They accomplish this by reviewing geological data, product marketing information, and government requirements for permits, public hearings, and environmental protection. Based on this review, they prepare rough cost estimates and economic analyses. If it appears possible to mine the deposit at a competitive price with an acceptable return on investment, mining engineers undertake a more detailed review.
Meanwhile, geologists continue to explore the mineral deposit in order to ascertain its dimensions and character. Once the deposit has been reasonably well defined, mining engineers estimate the percentage of the deposit that can be profitably extracted. This estimate, which takes into account the ore’s grade (value) and tonnage (volume and density), constitutes the minable ore reserve. It provides mining engineers with enough specific information to refine their economic appraisal and justify further analysis.
At this stage, engineers begin the process of selecting the most suitable mining method—one that will yield the largest profit consistent with safety and efficient ore extraction. In considering the adaptability of mining methods to the deposit, they rely heavily on rock mechanics and geologic data. Measurements of the stresses, strains, and displacements in the rock surrounding the ore body help engineers predict roof-support requirements and settling of rock masses during excavation. Evaluation of the deposit’s geologic features (such as the dimensions, inclination, strength, and physical character of the ore and overlying rock) enables engineers to place mine openings in stable rock, avoid underground water, and plan overall excavation procedures. If the evaluation calls for surface mining, engineers must decide where to dig the pits and where to put the rock and soil removed during mining.
Having estimated the ore reserve, chosen a mining method, and begun mine planning, engineers can determine daily (or yearly) mine output tonnage in light of product demand. They also select equipment and help plan and size the mine’s plant, support, ore processing, and shipping facilities.
For underground mining, mining engineers must determine the number and location of mine shafts, tunnels, and main extraction openings. They must also determine the size, number, kind, and layout of the various pieces of equipment. If the project continues to appear economically viable, construction begins.
As actual mine-making proceeds, mining engineers supervise operations. They train crews of workers and supervisors. The stress fields around the mine workings change as the mine expands. Engineers and engineering technicians must inspect the roof of underground cavities to ensure that it continues to have adequate support. Engineers must also continually monitor the quality of air in the mine to ensure proper ventilation. In addition, mining engineers inspect and repair mining equipment. Some mining engineers help plan ways of restoring or reclaiming the land around mine sites so that it can be used for other purposes.
Some mining engineers specialize in designing equipment used to excavate and operate mines. This equipment typically includes ventilation systems, earth- and rock-moving conveyors, and underground railroads and elevators. Engineers also design the equipment that chips and cuts rock and coal. Others select and determine the placement of explosives used to blast ore deposits.
Mining engineers also work for firms that sell mining supplies and equipment. Experienced mining engineers teach in colleges and universities and serve as independent consultants to industry and government.
Mining Engineer Career Requirements
To meet the standards set by most engineering colleges, high school students should take as much math and science as possible. Minimum course work includes elementary and intermediate algebra, plane geometry, trigonometry, chemistry, and physics. Courses in solid geometry, advanced algebra, and basic computer functions are highly recommended. In addition, many engineering colleges require three years of English (preferably emphasizing composition and public speaking) and social science (especially economics and history). Course work in foreign languages also is helpful, because many engineers work overseas.
A bachelor’s degree in engineering, preferably with a major in mining engineering, from an accredited engineering program is the minimum requirement for beginning mining engineering jobs. The organization that accredits engineering programs in the United States is the Accreditation Board for Engineering and Technology (ABET). ABET-accredited mining engineering programs assure students that their education will prepare them for professional practice and graduate study.
In a typical undergraduate engineering program, students spend the first two years studying basic sciences, such as mathematics, physics, and chemistry, as well as introductory engineering. Students must also study such subjects as economics, foreign languages, history, management, and writing. These courses equip students with skills they will need in their future work as engineers. The remaining years of college are devoted mostly to engineering courses, usually with a concentration in mining engineering. Engineering programs can last from four to six years. Those that require five to six years to complete may award a master’s degree or provide a cooperative engineering education program. Cooperative programs allow students to combine classroom education and practical work experience with a participating mining company or engineering firm.
After completing their formal studies and landing a job, many mining engineers continue their education. They take courses, attend workshops, and read professional journals in order to keep up with developments in their field. Continuing education also enables them to acquire expertise in new technical areas. Some mining engineers pursue advanced degrees. A graduate degree is needed for most teaching and research positions and for many management positions. Some mining engineers pursue graduate study in engineering, business, or law.
Certification or Licensing
Regardless of their educational credentials, mining engineers normally must obtain professional certification in the states in which they work. Professional registration is mandatory in all 50 states and the District of Columbia for mining engineers whose work may affect life, health, or property or who offer their services to the public. Registration generally requires a degree from an ABET-accredited engineering program, four years of relevant work experience, and passing a state examination.
Certain characteristics help qualify a person for a career in mining engineering. These include the judgment to adapt knowledge to practical purposes, the imagination and analytical skill to solve problems, and the capacity to predict the performance and cost of new processes or devices. Mining engineers must also be able to communicate effectively, work as part of a team, and supervise other workers.
Exploring Mining Engineer Career
To learn about the profession of mining engineering, you may find it helpful to talk with science teachers and guidance counselors and with people employed in the minerals industry. You might also wish to read more about the industry and its engineers.
Companies and government agencies that employ graduates of mining engineering programs also hire undergraduates as part of a cooperative engineering education program. Students often enter such programs the summer preceding their junior year, after they have taken a certain number of engineering courses. They normally alternate terms of on-campus study and terms of work at the employer’s facilities.
On the job, students assume the role of a junior mining engineer. They report to an experienced engineer, who acts as their supervisor and counselor. He or she assigns them work within their capabilities, evaluates their performance, and advises them as though they were permanent employees. Students have ample opportunity to interact with a diverse group of engineers and managers and to ask them about their work, their company, and mining engineering in general. Participation in the actual practice of the profession can help students assess their own aptitudes and interests and decide which courses will be most useful to them during the remainder of their engineering program.
There are approximately 5,200 mining and geological engineers employed in the United States. Approximately 40 percent work in the mining industry itself; the others work for government agencies or engineering consulting firms.
Beginning mining engineers generally perform routine tasks under the supervision of experienced engineers. Some mining companies provide starting engineers with in-house training. As engineers gain knowledge and experience, they receive increasingly difficult assignments along with greater independence to develop designs, solve problems, and make decisions.
Mining engineers may become directors of specific mining projects. Some head research projects. Mining engineers may go on to work as technical specialists or to supervise a team of engineers and technicians. Some eventually manage their mining company’s engineering department or enter other managerial, management support, or sales positions.
The U.S. Department of Labor reports that median annual earnings of mining and geological engineers were $69,370 in 2004. Salaries ranged from less than $42,150 to more than $119,110.
According to the National Association of Colleges and Employers, new graduates with bachelor’s degrees in engineering, including mining and mineral engineering, received starting offers averaging $49,715 a year in 2005.
Engineers who work for the federal government in its mining operations tend to earn slightly less than their counterparts in private industry.
Engineers in the mining industry generally work where the mineral deposits are situated, often near small, rural communities. But those who specialize in research, management, consulting, or sales may work in metropolitan areas.
For those who work at the mine sites, conditions vary depending on the mine’s location and structure and on what the engineer does. Conditions in the underground environment differ from those in surface mining. Natural light and fresh air are absent; temperatures may be uncomfortably hot or cold. Some mines have large amounts of water seeping into the openings. Potential hazards include caving ground, rockfalls, explosions from accumulation of gas or misuse of explosives, and poisonous gases. Most mines, however, are relatively safe and comfortable, owing to artificial light and ventilation, protective clothing, and water-pumping and ground-support systems.
Many mining engineers work a standard 40 -hour week. In order to meet project deadlines, however, they may have to work longer hours under considerable stress.
Mining Engineer Career Outlook
The demand for mining engineers is expected to decline through 2014 because of predicted low growth in the demand for coal, metals, minerals mining, as well as the demand for products made from stone, clay, and glass. Petroleum, natural gas, and nuclear energy are more readily available at more reasonable prices. The employment rate for mining engineers in the United States also depends on the price of coal and metals from other countries.
Despite this prediction, opportunities for mining engineers should be good for several reasons. Many mining engineers are nearing retirement age. Since few students major in mining engineering, these vacant positions may not be completely filled by new graduates. Additionally, U.S. mining engineers are increasingly sought after to work on projects in foreign countries. Mining engineers who are willing to work in foreign countries will have strong employment prospects.
Shortages in our natural resources will also create new opportunities for mining engineers. As mineral deposits are depleted, engineers will have to devise ways of mining less accessible low-grade ores to meet the demand for new alloys and new uses for minerals and metals.