Mining Artifact Archive | Beneath the Crust | Cyber Summer Camp

ARTIFACT ARCHIVE

MINING

OVERVIEW

Below you will find related activities for today's topic of

geology. Through the webinar and exploring Artifact Archive

you'll learn so much about mining, and so much more!

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need to read everything in the Artifact Archive to complete advancements.
Younger youth can explore as much as they want and may need the help of
an adult.

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WEBINAR WITH EXPERTS

Click below to find the Zoom webinar with geologist and expert, Tim Parker.

About Tim Parker

Mr. Parker serves as the Chief Technical Officer of Encino Energy. Mr. Parker founded Ardent Exploration LLC where he served as President and CEO. He was the CEO of HighMount E&P, a subsidiary of Loews Corporation (acquired from Dominion). Mr. Parker was Senior Vice President, Exploration & Production at Dominion Exploration & Production, Inc. (“Dominion E&P”). He was responsible for all operational activities in four business units spanning 10 basins in North America, including the most active drilling program in the U.S. in 2004-2006. Mr. Parker spent 23 years at Santa Fe Snyder Corporation, including as President, International and EVP, Exploration. He holds a Bachelor of Science and a Master of Science (with a Sedimentary Geology emphasis) from Stanford University.

INTRODUCTION

Mining is the removal of materials from the earth that are valuable in creating products and services that people find useful. Miners have a saying: "If it can't be grown, it has to be mined." Look around your room. Notice everything that was made from something grown, like wood or cotton. Now look at all the things in the room that were not grown, such as plaster, glass, and metallic objects. These were made from minerals that were mined from the earth. Yet even the things that were grown required equipment for their planting, cultivation, and harvesting this equipment was made from minerals.

EARTH'S MINERAL WEALTH

How important is mining to society? From communications, transportation, power, construction, agriculture, and medicine to education, entertainment, and recreation, every aspect of society relies on mining. Whether it's a car, computer, surgeon's scalpel, smartphone, television, goalpost, or almost any other object you can name, the materials for making it (or for making the machines that produce it) must come from a mine.

Rapid communications, information technologies, and the ability to store,

retrieve, and transmit data for education, industry, and recreation—such as

video games and music downloads—are important to us. Mining provides

the raw materials for all the hardware for these conveniences. For example,

a car has about 34 minerals and metals, and a smart phone requires 30

minerals and metals—all were extracted from the earth.

Mining produces coal for generating electricity, and as a raw material for

many industrial processes. Uranium for nuclear power is also mined. Even

the devices needed to harness solar and wind energy are made from

minerals that come from mining.

THE IMPORTANCE OF MINING

In geology, a mineral is a naturally occurring crystalline substance with its

own chemical formula and its own distinctive physical properties. A rock

may be made up of one or more minerals.

In mining, the term mineral has a wider meaning. It refers to all the substances that are extracted from the earth for human use. Mined minerals are classified as metallic, energy, or industrial.

Metallic elements and compounds conduct heat and electricity, are ductile (can be drawn or stretched into wire), malleable (can be hammered into sheets), and shiny. Examples are copper, aluminum, iron, and zinc.
Energy minerals supply electrical and mechanical power by their combustion. They can also be used as a feed stock (raw materials) for liquid transportation fuels and coke, which is used to make steel. Fossil fuels, such as coal, are energy minerals, and so is uranium, which provides power by the heat from radioactive decay.
Industrial minerals are neither metals nor fuels, but are mined because we use them every day: in construction, in manufacturing, and even in the food we eat. Examples include clay, sand, limestone, gypsum, and pumice.

Your home is built of mineral products that were mined. Are the outside walls of your home or apartment made of brick, stone, or aluminum siding? All had to come from a mine at one stage or another. In a typical home, the inside walls are wall-board made of gypsum. The foundation is concrete with crushed stone in it, and the roofing shingles contain fine crushed stone. Windows are made by combining silica sand, dolomite or limestone, and soda ash. Appliances are made mostly of metals. Paint has mineral pigments. Except for wood doors and window frames, wood framing, and the like, most of your home and everything in it came from mines and quarries.

The power to heat and cool homes and to run entertainment and communications devices comes from minerals such as coal and uranium. Electricity generated from energy minerals is transmitted long distances on metal wires—aluminum and copper. Minerals are essential for affordable and convenient electricity on which we depend. Transportation depends on the products of mining. Bicycles, automobiles, trucks, ships, and airplanes are made from minerals. Highways and airport runways are made of quarried crushed stone bonded with asphalt or cement—all minerals.

Even things we think of as organic (grown) depend on mining. For example, paper made mostly from wood pulp may have limestone or kaolin (fine white clay) as a mineral filler or coating. Wood products and food crops are grown using fertilizers that are mined: phosphorous (phosphate), potassium (potash), and magnesium (dolomite). The manufacture of farm equipment for cultivating and harvesting crops also depends on the mining industry. Farm machinery is made mostly of steel (made from iron and carbon), with copper for wires, aluminum in engine blocks and wheels, lead in batteries, and chrome for trim.

At mealtimes, you use all sorts of minerals. You eat with metals-stainless steel utensils. You cook with power from energy minerals. You eat off ceramic dishes, and drink from glass containers—made from industrial minerals.

What's In Your Phone?

Producing a typical smartphone calls for the following metals and elements found in minerals: aluminum, antimony, beryllium, cadmium, carbon, chromium, cobalt, copper, gallium, gold, indium, iron, lanthanum, lead, lithium, manganese, mercury, neodymium, nickel, nitrogen, oxygen, palladium, platinum, silicon, silver, tantalum, tin, tungsten, vanadium, zinc.

MINERALS IN A BICYCLE

MINING IN EARTH'S HISTORY

People have depended on Earth's mineral wealth throughout history. Periods of human civilization are named for these materials—the Stone Age, Bronze Age, and Iron Age. In prehistoric times, humans made stone tools and weapons: arrowheads, spear points, knives, axes, and hammers, among other objects. People adorned themselves with necklaces, rings, and amulets made of stone, and they shaped clay into pots and other containers.

Metals such as copper, gold, and silver, found on or near the surface of the ground, were first used as decoration. Gold was easily noticed in streambeds because of its bright yellow color. It was easy to pound and stretch into desired shapes, often as jewelry and as objects of art and worship.

For early humans, copper served many practical purposes: tools, weapons, jewelry, and decoration. Although copper is brittle in its native state, people learned to make it more workable by heating it in a fire annealing). Heating also melted the copper out of the rocks that contained the metal—a process known as smelting.

Early metalworkers discovered bronze by smelting together rocks that contained both copper and tin. Bronze is harder, less brittle, and more durable than copper, tools and weapons of bronze were better able to maintain a sharp cutting edge. The Bronze Age was named for the metal; its properties made it so significant in human history.

With technological advances came the Iron Age, when iron and steel became extensively used, especially for cutting tools. Smelted iron was hammered into the desired shape to make steel swords and other weapons and tools.

In ancient Rome, soldiers carried steel swords, and they were sometimes paid with another mineral: salt. In fact, the word salary comes from the Latin word for salt, salarium. It was important to Romans as a food preservative and seasoning. The Romans built roads to make it easier to ship salt into the city. For instance, the Via Salaria, a road between the Adriatic Sea and Rome, made the delivery of highly valued sea salt faster and easier.

As important as salt was to the ancient Romans, an even more valuable mineral-gold-helped to shape the history of North America. It sparked mass migrations of people in search of their fortunes. After gold was discovered at Sutter's Mill, California, in 1848, more than 300.000 people traveled to California over the next seven years. Known as the Forty-Niners, the newcomers came by land and sea, helping to settle the western United States.

The Klondike Gold Rush of 1896-1899 brought more than 100.000 gold seekers to Alaska on their way to the Yukon region of northwest Canada. The harsh conditions stopped many, but then in 1899 gold was discovered in Nome, Alaska, triggering another mad dash by gold prospectors.

THE KLONDIKE GOLD RUSH

Gold was not the only valuable metal found in the American West. When silver was discovered in the Comstock Lode in 1859, Virginia City, Nevada, became a bustling boomtown almost overnight. San Francisco, California, grew into a major financial center because its banks funded the mining. Comstock Lode silver helped finance the Union in the Civil War (1861-1865).

Because legal battles were waged over claims ownership, the U.S. Congress in 1866 passed the first law to govern how Americans could prospect and mine on federal public lands. Then in 1872, Congress passed the General Mining Act, which is still in effect today.

ONE MINER'S STORY: JOHN W. MACKAY

John William Mackay (1831–1902) was born in Dublin, Ireland. His immigrant parents came to New York in 1840. As a 20-year-old, Mackay made his way west, hoping to strike it rich with the rest of the Forty-Niners during the California Gold Rush. He didn't find much gold, but in 1873 he struck the Big Bonanza, one of the greatest silver veins ever found. In just four years, the Big Bonanza mine in Nevada produced over $400 million in silver. As senior partner, Mackay kept the largest share for himself. When the silver played out in 1877, he and his partners moved to San Francisco as millionaires.

Mackay was a great philanthropist. He donated generously to the Nevada School of Mines, originally established in 1888 and renamed The Mackay School of Mines to honor its benefactor. Today the school is called the Mackay School of Earth Sciences at the University of Nevada, Reno. The school has graduated generations of mining professionals who have worked throughout the world.

In what other ways have minerals influenced history? Consider this more recent example. In the 1920s and 30s, the Empire of Japan sought to conquer its Asian neighbors. Japan needed iron and petroleum, which it did not have in large amounts. China and Southeast Asia, however, were rich in these mineral resources. To stop Japan's aggression, the United States cut off shipments of iron and steel along with oil exports to Japan Japan considered this an act of war, and on Dec. 7. 1941, the Japanese attacked the U.S. Navy battleship fleet at Pearl Harbor, Hawaii. Japan's surprise attack brought the United States into World War II.

There are many steps in finding the mineral resource; planning, constructing, and operating the mine. Then closing the mine after the resource is removed.

WHERE TO FIND MINERALS

Button

Click on the map above or this link to access an INTERACTIVE map of mines in the United States

The U.S. Geological Survey (USGS) Mineral Resources Data System catalogs information about mineral resources around the United States and the world. Using the map tool, users can zoom in to obtain reports and data on past and present mines, mine prospects, and processing plants. Only 2.5 of every 1,000 acres in North America are occupied by mines. From this small area come all the minerals we use.

MINING ENTERPRISES IN YOUR AREA
mining in society merit badge requirement

For requirement #2, use the map above to mark the locations of 5 mining enterprises in your area. Then look up what resource is being processed at each location.

Or simply google "Mining Enterprises in ____________ (your state or area) to find a better map. For example, click this link for mines in Ohio.

MAJOR SOURCES AND USES OF MINERALS

The following charts list minerals, their major sources, and their main uses. Note how many mineral resources are mostly or entirely mined outside of the United States.

INDUSTRIAL MINERALS

METALS

ENERGY MINERALS

EXPLORING FOR MINERALS

In mining, exploration is the search for a useful mineral that can be extracted from Earth's crust. When you think of exploration, you might imagine an old-time prospector with his trusty mule. With his pick and shovel, off he would go in search of something valuable. One common method of exploration was to find a place that had geology similar to a known ore deposit. For example, in 1849 in California, prospectors who knew that gold could be found in some streams would pan for gold there.

Panning is a method of separating gold from other particles. Small amounts of gravel and sediment from the streambed are put in the pan. The pan's contents are swirled gently, allowing lighter materials to wash out of the pan. Heavier particles fall to the pan's bottom. Any gold will remain in the bottom of the pan.

The prospector would follow the gold upstream, panning every so often, seeking the "mother lode," or major ore deposit. When he stopped finding gold in the sediments, he would backtrack to locate where the gold was entering the stream, narrowing his search. Traditionally, once found, a miner would shout, “Eureka!"-Greek for, "I found it!"

MODERN EXPLORATION METHODS

Many old methods are still used, but today's "professional prospectors" have more high-tech ways of locating the right geological conditions for the kind of deposit being sought. Modern-day specialists include geologists, geochemists, mining engineers, metallurgists (experts in metals), and logistics specialists (experts in handling the details of an exploration venture).

In their planning, exploration teams often use remote-sensing. Satellites collect and process

data using different detection methods from photography to multispectral scanning. Some

methods that use laser technology even allow scientists to see through" trees and vegetation

to the ground beneath.

Because we can't see below Earth's surface to identify deposits underground, the team

relies on geophysical methods that measure differences in gravity, magnetism, and electrical

resistance. For shallow studies, the team may use ground-penetrating radar. Seismic

techniques give the team a picture of underground rock formations, similar to how

earthquakes are located and measured.

Mineral rights are property rights that allow the owner to extract minerals within an area,

they may be separate from surface property ownership

STEPS IN EXPLORATION

An exploration team always plans ahead. Team members first read the scientific literature about the area and the type of mineral deposit they are seeking. This research helps make the most of valuable field time. The team determines what tools to use for exploration. Basic tools used in the initial fieldwork include a sturdy field vest or backpack, maps and GPS devices, a compass, a hat that provides shade, a full canteen, good hiking boots, a jacket, eye protection, a rock hammer, sample bags, a notebook and writing instrument(s), a pocketknife, a weak acid solution, and sometimes a four-wheel-drive vehicle.

The team then sets a timetable for when the work will be done and prepares a budget to determine how much the project will cost. Good communications are essential so the team members location, and when they plan to return, is always known. Land ownership is an important consideration. The exploration team needs to avoid trespassing (exploring on land without authorization). Local government offices have records of land ownership as well as information on who owns the mineral rights.

Besides asking the surface owner(s) for permission to prospect on a piece of land, the team may need to get permits from local, state, or federal government agencies before exploration on the ground begins. Typically, a team has specialists who find out about land ownership and obtain the necessary permits.

DRILLING AND IMAGING

If the fieldwork uncovers good signs of valuable minerals, the next step may be to drill core holes. This allows the geologists to see underground. Drilling also provides more geochemical or geophysical data. The exploration team enters all the data collected into a computer, constructing a geological model of the mineral resource. With enough data, a three-dimensional computer image can be created to show what the mineral deposit looks like underground.

Mining software uses prospecting data to build images of mineral deposits. This “slice" through such a model provides a 3-D view.

The next phase of exploration involves additional drilling of the mineral deposit. This helps determine the concentration of an element or a compound, along with other characteristics that allow it to be mined and processed. Once team members know how big the deposit is and what the grade is, they calculate the amount of the resource present. The resources calculation estimates how much ore is in the deposit. If the analysis is positive, then the next step is mine planning to see if mining is feasible.

One basic method that has long been used is to conduct an assay. Just as an 1849 California prospector might bring in a rock sample to have its composition analyzed, so do modern prospectors. By a series of chemical and physical tests, assaying reveals the elements of a rock sample. If an element of value has a high enough concentration, then an exploration program may follow. Some people choose exploration as a career because much of it is done outdoors.

Rules Of Thumb For Geological Modeling20190916170021987.jpg

MAJOR STEPS IN EXPLORATION

Library studies identify geological formations that may hold a mineral.
Remote sensing may help to identify places to send an exploration team.
Fieldwork planning is completed (obtaining permits, getting permission to explore the site, etc.).
After examining the surface, more tests, like drilling, may be necessary.
Field data is used to build a computer model of the mineral deposit.
If there is potential economic value, core drill sampling is done.
Enough data is collected to confirm the size and quality of the deposit.
If the deposit still has potential economic value, mine planning begins.

MINE PLANNING & OPERATIONS

If you're preparing to write a report for school or take a hike, your first step is to make a plan. You may plan by yourself, or have help from friends and family. The same is true in organizing a mining operation. Mine planning is the realm of the mining engineer, supported by geologists, metallurgists, and others.

Planning a new mine takes several steps as seen in this illustration. The steps are all connected. For instance, mine design and safety go hand-in-hand: land reclamation and mine closure may occur at the same time.

MAJOR CONSIDERATIONS

When identifying resources that could be mined, mining engineers (with the geologist) review the site information and analyze geographic, geologic, technical and economic information. As mining engineers calculate the resources that are recoverable (obtainable), they evaluate all the advantages and disadvantages of the mine site. This tells if it is feasible to mine and process resources economically and legally. A feasibility study completed at this point allows the mining company, bank(s), or investor(s) to decide if the project is worth their spending additional funds on it.

Resource control confirms ownership of land and minerals through lease or purchase. If the mineral is privately owned, surface and mineral owners and the mining company must all negotiate contract agreements to build the mine and share the profits.

When state or federal governments own the minerals in the ground, a U.S. citizen or corporation may stake a mining claim on land over the mineral occurrence. A claim owner has the right to possess and extract any minerals under the claim starting on the date the claim was located. There are several kinds of claims. Lode and placer claims are named for the type of mineral deposit under it. Mill site and tunnel site claims are necessary to locate and erect mills and other structures for mineral processing. We'll use a lode claim on federal land to describe how to locate a mining claim.

To locate a lode claim, you have to discover a valuable mineral there. Next you erect claim posts at the point of discovery and at each of the four corners of the claim. You then attach a location notice at the discovery post. Posted information typically includes the name of the claim, date of location, county and state, description of the land by township and range, name and address of the locator (you), and a map of the claim. You must record this within 90 days with the U.S. Bureau of Land Management, the agency that administers all land owned by the U.S. government. You pay any filing fees at the time you record the claim.

Permitting a new mine can be a lengthy process, typically five years or more. A mine plan must meet all government rules, including local ordinances, to protect air, water, land, and wildlife. Permits are needed in several categories, including:

Mining
Reclamation
Water discharge
Air emissions
Zoning
Safety
Wastewater control
Explosives material handling and storage

Local, state, and federal agencies review and approve permits. Interested people and groups can learn about the mine plan and comment on it beforehand. Mine construction begins once permits are approved and the mining company posts a bond (a financial guarantee) to ensure that funds will be available for reclamation.

Infrastructure includes roads, water wells, gas pipelines, buildings, and electric power lines that are already there. In addition, mining infrastructure needs to be built. The mine may require haul roads: shafts; elevators; additional power, fuel, and water utilities: office facilities: showers and lockers for miners, warehouse and maintenance buildings, material handling, processing, disposal, and transportation facilities, and drainage and sediment-control systems (such as sediment ponds and ditches). Parts of the existing infrastructure may be unaffected, relocated, or mined around. Mine infrastructure is built so that it doesn't interfere with mining operations. For example, processing plants should not be constructed directly over minable resources.

Mine design varies according to the mining method. Plans for a surface mine take into account the shape of the pit, the amount of material to be handled, and the sequence of mining. Plans for an underground mine set the location of shafts, slopes, entries, ventilation systems, and roof supports, and the sequence of mining. Detailed plans and cost estimates determine whether a mine is economically feasible. The success or failure of the mining operation often depends on the success of the design phase.

Mine closure and land reclamation shuts down the mine and restores the site to a natural condition or to a useful purpose. Former mine sites are reshaped and contoured so they blend in with the surrounding area, restored sites are then replanted with vegetation. Reclamation of underground mines tends to be less involved because affected areas are smaller than for surface mines. When government authorities declare reclamation successful it allows the release of bonds posted before the mining started.

Long-term monitoring of a restored site is often necessary if there is a special concern. Examples may include specific needs for revegetation or perhaps erosion control.

Even after mining begins, mine planning doesn't stop. Ongoing mine planning can be short-term or long-term. Short-term planning typically covers less than five years, focusing on current mine operations, production goals, and economic budgets. Long-term planning extends more than a year beyond current mining activity. It provides detailed plans for at least 10 years as well as general plans for the life of the mine.

TYPES OF MINING

The type of mine is determined by the size and shape of the mineral deposit how deep it is, and
the kind of rock that surrounds it. The main types of mineral deposits include tabular, massive,
vein, and placer.

Tabular. The mineral deposit is basically horizontal and fairly uniform in thickness, like a
slab or countertop. It can be at the surface or thousands of feet below. Examples of minerals
found in tabular deposits are bituminous and lignite coal, limestone, salt, and trona (sodium
carbonate or soda ash). Many tabular deposits like coal, gypsum, and potash may have layers
of unwanted rock types in between
Massive. The mineral deposit lies within a large rock formation and is usually hundreds of
feet thick and thousands of feet wide. It can be at the surface or thousands of feet below.
Massive mineral deposits include metals like gold, silver, copper, lead, and zinc.
Vein. The mineral deposit is a narrow sheetlike seam of mineral crystals within a host rock.
Veins come from crystal growth on the walls of fractures in rocks. They usually are inclined
(tilted). Some minerals found in veins include gold and silver. Steeply inclined anthracite coal
formations resemble vein deposits, but they developed by folding and faulting tabular
deposits.
Placer. The deposit is an accumulation of minerals in loose sand and gravel. Streambeds
and beaches are the usual sites for placers. They are mined for gold, platinum, diamonds,
titanium, and uranium.

The mining engineer decides how to mine a mineral deposit safely with the least environmental
impact and at the lowest cost. Surface mining is usually the first choice if the mineral deposit is at
or near the surface. If it is deep below the surface, then underground mining is required. The
majority of all mined substances are mined by surface methods. Tabular, massive, and placer-type
deposits are mined this way.

SURFACE MINES

Surface Mines In a surface mine, the unwanted material above the mineral deposit is called the overburden. Mining starts when the overburden is removed by blasting and excavating. Once the mineral deposit is exposed, miners load the ore mineral into haul trucks or conveyor belts to transport it to a mineral processing plant.

Surface methods usually involve moving large amounts of material at a relatively low cost per ton or per cubic yard. A surface mine almost always appears larger than an underground mine that produces the same mineral because all the mine-works are visible. Underground mines can be the size of cities, but are hidden from view. Many underground mines range up to 24 square miles, as large as the island of Manhattan.

EXAMPLES OF SURFACE MINES

Open-pit mine. This type of mine is typically used for massive deposits close to
the surface. A quarry is a common open-pit mine. Quarries produce building
materials such as sand, gravel and stone. Quarries are often located near
populated areas where the construction materials are used, so cooperation
between the mine and its neighbors is essential.
Strip mine. This type of surface mining is generally used for tabular deposits.
The picture shows a strip mine in a coal deposit. Mine planners carefully design
the angle of the rock wall (above the coal) so that it does not fail during mining.

Notice the benches and roadways around the inside of Utah's Bingham Canyon, an open-pit copper mine. Bench design helps maintain the stability of the mine wall. Haul roads are required to remove rock from the pit.

SURFACE MINING EQUIPMENT

Surface mining requires huge equipment. For example, the largest bucket from a modern rubber-tire loader, used to excavate the blasted minerals and rocks, can hold 53 cubic yards. That's 160,000 pounds of material, which is equal to the weight of about 40 pickup trucks.

UNDERGROUND MINES

Underground mining is more selective in the way minerals are extracted. Under-ground mines

require careful designing and planning with more structures than surface mines. The necessary

structures include shafts, hoists (elevators), ventilation fans, underground maintenance shops,

and conveyance (transport) systems.

The geometry, or shape, of the deposit determines which underground method to use. No two

mineral deposits are identical, so the mine design is customized to the size, shape, and location

of the deposit.

EXAMPLES OF UNDERGROUND MINES

Room and pillar. This mining method extracts minerals (tabular and massive) from a
series of rooms” along horizontal openings. Because part of the deposit is left behind as
support pillars to hold up the mine roof, it is not the most efficient method. Each pillar
tends to be the same size and shape for a particular mine, forming a pattern like a
checkerboard when viewed from above. Room-and-pillar mining is used to extract coal
and metal ores, stone, talc, soda ash, salt and potash. Most underground mines in the
United states use the room-and-pillar method.
Longwall mining. In a longwall mine, a panel of coal or trona, measuring about two miles long and 750 to 1,500 feet wide, is cut by shearers (or plows) moving back and forth along the mine face (wall). Conveyors bring the mineral to the surface. Heavy-duty shields protect the miners working along the face and the shearing edge itself. As the shields move forward, overlying rock falls behind them into the empty spaces that were just mined. The fallen rock is known as gob.
Block caving. This method mines large, low-grade ore bodies that are vertical or slightly inclined (massive or veins). The ore body is undercut (dug out from underneath), or undermined, over a large area. Then it is drilled and blasted above the undercut rock opening. The rock mass drops into draw bells and is removed at loading draw points, then conveyed or hoisted to the surface for processing.
Stoping. Stoping is used when surrounding rock is strong enough to prevent a cave-in of the stope, or open space. Vertical shafts reach down to the ore body (massive or vein). Miners remove the ore along horizontal levels, or tunnels. Stoping is used to mine large deposits of gold, silver, lead, platinum, molybdenum, and many minerals.

SURFACE SUBSIDENCE

When minerals are removed from underground mines, the surface above may subside or sink. A room-and-pillar mine generally has no subsidence on the surface, unless the pillars fail after the mine closes. However, longwall or block caving methods will—by design—cause surface subsidence. So precautions are necessary to avoid mining under surface structures (buildings, highways, etc.) and may call for a plan to restore the surface structures after mining ends.

Many areas rely on groundwater for irrigation or drinking water. When there is subsidence, the water supply can be disrupted. In most cases, the interruption is temporary; in others it is permanent. Mining companies are required to provide alternative sources of water if they are responsible for water loss or poor water quality.

MINING PROCESSESING

Companies mine minerals to sell at a profit to customers who need and demand them. However, most minerals cannot be sold immediately after they are extracted, because customers can't use them in that form. Mineral processing gets the minerals ready for the customers. Processing converts rock into a form that is usable, transforming it into such things as a gold bar, or separating it into different sizes for sand and gravel, or in the case of coal, it's cleaned to reduce pollution when it's burned. Mineral processing can be simple with only a few transformation steps, or it can take many steps to release the minerals or metals. Each step uses specialized tools and equipment. The equipment used in modern mineral processing is huge, highly automated, and worth millions of dollars.

PROCESSING METHODS

Separating and purifying an ore into a useful product can be difficult. In gold-bearing ores,
for example, the gold particles may be microscopic. The mining industry has found ways to

recover gold from grades as low as 0.01 ounce of gold per ton of ore. To put it another way,

a ball of gold ore 3 feet in diameter would contain the equivalent weight in gold of only 10

Cheerios (one-hundredth of an ounce).

ROCK CUTTING

Dimension stone is natural stone or rock that is cut to specific sizes or shapes. To make dimension stone, diamond saws and wedges separate large blocks of rock in quarries. The blocks are cut into smaller pieces: from small slate roofing tiles and walkway pavers to large rectangular slabs for granite kitchen and bath countertops and marble monuments or interior walls.

Did you know?

One responsibility of the mineral processing engineer and metallurgist is devising methods to remove valuable minerals from the ore rock after it is hauled out of the mine.

ROCK CUTTING

STONE CRUSHING

MATERIAL SEPARATION

To separate different sizes of materials, screens are used. A mixture of sand and gravel may be fed into a series of screens to separate the various sizes. The fine sand might be used in a sand trap on a golf course, while the gravel could be used to make concrete or road base.

CRUSHING AND GRINDING

Many mineral processing plants have equipment to break different sizes of rocks into smaller ones. Large, heavy-duty crushers can reduce boulders the size of an automobile. Some crushers pinch the rocks between moving walls and fixed walls, much like a hammer and anvil.

Other kinds of crushers drop the rocks onto hard materials or other rocks to break them. In coal processing, for example, the coal is softer than the rocks, so the coal shatters. Rotary breakers reduce the size of the coal, which passes through holes in a drum. The larger rocks are rejected out one end. After going through a crusher, rocks may be ground to a fine powder using a mill. A mill is a cylinder or drum filled with rock, water, and steel balls or rods. As it rotates, the steel balls crush and grind the rock into tiny particles making it possible later to separate the mineral from the waste rock. Modern grinding mills may be

up to 40 feet in diameter, and use 30,000 horsepower. A typical family car may have only

200 horsepower.

Grinding releases the individual mineral crystals that make up the rock. Once the different

mineral crystals are separated, they can be concentrated for higher purity. Separation

methods use the different physical and chemical properties of distinctive mineral crystals. For

example, magnetic separators concentrate magnetic mineral crystals, such as magnetite, from

nonmagnetic mineral crystals, such as quartz.

CYCLONE SEPARATION

Coal coming directly from the mine is contaminated with heavier rock and sulfur-bearing minerals such as pyrite. A type of gravity separator called a cyclone is used to separate out the lighter coal. The cyclone swirls a slurry (a mixture of water and solids) of pulverized coal and rock.

FLOTATION

Flotation is a chemical process for separation using a vat, or flotation cell, filled with water

and a chemical called a flotation agent. Tiny ore mineral particles are added to the cell to form

a slurry. Agitating it creates air bubbles, which mix with all the tiny particles. The air bubbles stick to

the valuable mineral particles, lifting them to the surface to be skimmed off as foam: the waste minerals

sink. In some cases, the desired mineral sinks and the waste minerals float to the top.

CHEMICAL PROCESSES

Some minerals can be chemically dissolved, then recrystallized or precipitated into a highly pure solid form. Examples include titanium dioxide used in sunscreen to block ultraviolet radiation; sodium carbonate used in baking soda, and table salt formed by the evaporation of seawater. Some metal mines use a technique called heap leaching to chemically dissolve and separate valuable metals such as gold, copper, and silver from a pile of crushed rock.

SMELTING

Metal-containing minerals are concentrated by mineral processing and shipped to a smelter where high temperatures transform the metal-bearing mineral into pure metal. During smelting a flux, such as limestone, is added to the molten metal to combine with unwanted impurities called gangue. The combined gangue and flux form slag

that is separated from the molten metal. The molten metal is then poured into a

mold to make very pure bars or ingots. Smelting involves a chemical change to

the raw material, but in refining, the final material is usually chemically identical

to the original one, only purer.

REFINING

Refining is usually the last step in processing metals. After smelting, a metal is

dissolved in acid and electroplated (deposited in a thin layer by electrolysis) as an almost pure metal. In copper production, the copper coming from the smelter may contain impurities such as arsenic. The copper is dissolved in acid and then plated out in a way similar to how a car battery works, by creating an electric current. The pure copper is sold to make wire or other products.

CALCINATION

Another process of heat-treating rock or mineral is called calcination. In one example, calcination is used to transform calcite, the major component in limestone, into lime. (This was mentioned in the "Rocks and Minerals" section). Gypsum is calcined at 250 to 300 degrees Fahrenheit to remove the water of crystallization as water vapor. Calcined gypsum is called stucco.

WASTE PRODUCTS

After processing ore to recover valuable minerals, the leftover materials are called refuse, gangue, or tailings. These must be disposed of in an environmentally safe manner. Disposal facilities are designed to hold all the waste generated during decades of mining and processing plant operations.

Processing rocks and minerals is done in a plant that houses all the equipment and has storage space for ore, processed materials, and waste. Mineral processing requires moving and storing large volumes of rock, water, tailings, and finished products. Mineral processing plants can look very complicated with all the tanks, silos, conveyors, and pipes that transport materials from one stage to the next.

Did you know?

Gravity separators separate heavy, dense minerals such as gold from lighter rock fragments. An example of a simple gravity separator is the prospector's gold pan.

Make sure to visit the Lava Lab to complete a connected STEM activity!

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MINING IN THE FUTURE

In the future, mineral deposits most easily mined from Earth will be depleted. Miners will need to dig deeper and work in more challenging conditions to mine newly discovered deposits. Other potential sources of minerals exist beyond these, however. It may sound like science fiction to talk about mining the oceans or interplanetary space, but we already harvest minerals from the ocean. Also, detailed plans are in the works to mine the moon, near-Earth asteroids, and even other planets.

Miners have many reasons to look beyond the usual places for minerals. A mineral deposit in a remote location on Earth might not have water, electrical power, roads, or workers nearby, and the cost to install or obtain these might be excessive. In addition, the grade might not be high enough; that is, the mineral concentration might not be at the necessary level to cover the cost of the machines and processes to mine it. Also, an unfriendly country might control the only source of a certain mineral, charging high prices for it or preventing others from extracting it. Wars are sometimes fought over such resources.

Finally, the environmental cost of mining the usual places” may be too high in terms of loss of species (biodiversity), water and air pollution, damage to Earth's natural landscapes, or any combination of these.

MINING IN THE OCEAN AND SEABED

If you have ever tasted ocean water, you know how salty it is. The ocean is Earth's greatest storehouse of minerals. Besides hydrogen and oxygen that make up water, the most abundant elements in the ocean are sodium and chlorine, the elements that form salt. While these elements come mostly from surface erosion of the continental landmass, most sodium is leached from the ocean floor and most chlorine is emitted from Earth's interior by volcanoes and hydrothermal vents.

Electrolysis removes magnesium metal from seawater in one step. The magnesium forms alloys with other metals, especially aluminum.

Other abundant elements dissolved in seawater are magnesium, sulfur, calcium, potassium, carbon, bromine, boron, strontium, and fluorine. Some are already mined from the oceans. You are eating salt harvested from seawater if the package says "sea salt." Common salt is obtained from seawater by collecting it in ponds where the sun's energy evaporates the water. The salt is left behind as sodium chloride crystals and is then harvested for consumption. Salt is used for seasoning and preserving food. It is also used in water softening and for deicing roads in wintertime.

Bromine, too, is extracted from seawater. It is used in flame retardants, water purification, particularly in swimming pools and hot tubs, pesticides: over-the-counter and prescription drugs, and photography. Iodine is mined from ocean water by harvesting seaweed. Its dry weight can have up to 0.45 percent iodine. Without iodine as a catalyst, or booster, plastic drinking bottles would not be possible. Other uses for iodine include pesticides, medical applications, pharmaceuticals, and stain-resistant chemicals.

The shallow near-shore realm concentrates some minerals. Gravel for concrete and beach reconstruction is mined by dredging the sea bottom close to shore. Titanium dioxide is mined along beaches and offshore sandbars as the minerals rutile, anatase, leucoxene, and ilmenite. These are heavier than the rest of the sand grains, so gravity processing easily separates them.

DEEP-SEA MINING

Volcanic activity and hydrothermal vents on the ocean floor yield iron, manganese, copper, cobalt, and zinc. Harvesting these requires deep-sea mining methods. The crushing pressure of the water, frigid temperatures, and total darkness are among the challenges of deep-sea mining. New exploration methods are needed—mobile exploration platforms for deep-sea drilling and mapping, and remote sampling techniques. Remote-control methods and robotics are likely answers to the challenges. Some minerals might be scooped off the ocean bottom at a depth of two to three miles (13,000 to 18,000 feet). Manganese nodules, composed mostly of manganese and iron compounds, might be mined this way. The nodules are valued for other metals they contain—copper, nickel, and cobalt.

For locating, sampling, and drilling these hard-to-reach deposits, new approaches are necessary. How can these minerals be dug from the ocean floor? How can they be brought to the surface? Can they be processed in factory ships or shipped to processing plants onshore? What is to be done with leftover materials after separating the desired metals? These are questions that still must be answered for a successful deep-sea mining operation.

PROTECTING THE MARINE ENVIRONMENT

The environmental impacts of ocean mining must be considered before launching any operations. Where unique marine habitats exist mine operations face restrictions.

Seasonal limitations may be necessary to protect marine organisms during special life stages such as breeding and egg or embryo development.
Dredging changes seabed topography which may
need to be restored.
Mining could displace certain bottom-dwellers.
Miners will need to consider how long it would
take for these organisms to recover and
reestablish colonies.
Miners will need to limit the amount of disturbed
seafloor sediment that increases cloudiness or turbidity (measure of light transmitted through water).

MINING IN SPACE

Most of the Apollo astronauts were not geologists, so they received extensive training in geology before their moon missions. It was essential for them to know about rocks before they landed. Rocks would reveal how Earth and the moon were similar and whether they shared a common origin.

In 1972, the last moon mission landed a geologist-astronaut on the lunar surface so that a better

geological assessment could be made. Harrison H. "Jack" Schmitt, holder of a Ph.D. in geology, could

expertly judge the rocky terrain and quickly saw the potential mineral wealth right at his feet. He later

proposed commercial ventures to mine lunar helium-3, which could theoretically be used for fuel for

nuclear fusion, replacing nuclear fission and fossil fuels.

Developing such space enterprises would help to use resources from space to support human space

activities and settlement, and help develop efficient and cost-effective ways to launch large payloads from Earth into deep space.

CHALLENGES OF SPACE MINING

Mining methods in space would resemble those on Earth, but adjusted for the absence of oxygen and differences in gravity. Surface methods will be used when minerals are at or near the surface. Devices will collect magnetic metals and minerals such as those associated with iron meteorites. Underground shafts will be dug when the target is a deep lode or vein. Space miners will likely melt ice to get water and to generate oxygen for breathing.

For interplanetary mining, the equipment would have to be shipped or manufactured in space on site, or shipped as parts from Earth, then assembled on-site. Space mining poses major transportation challenges at every stage that must yet be overcome. Designs are on the drawing boards, however, for space barges, space tugs, and power-generation systems.

Another issue is whether to process raw materials on-site, ship them to mills on Earth, or transport them to mills on specially designed space stations. Interplanetary shipping of large, bulky loads will be expensive, so processing on-site will probably be more cost-effective. This does not eliminate the problem since refined metals and maybe industrial minerals will have to be shipped, too.

Just like on Earth, an interplanetary exploration team must decide whether to use robot or human operators.

Hauling, crushing, and screening all depend on gravity to some extent, so these steps need modification for smaller cosmic bodies with less gravity. Enclosed circuits using magnetic, electric, or pneumatic air pressure) transport may solve the problem, or previously unforeseen technology may be developed. Flotation processes will face the similar challenges of low gravity, limited water, and exposure to the hazards of space.

High cost is the main concern for any space operation. Today it would take billions of dollars to explore, mine, and ship mere ounces of materials to Earth. Instead of bringing the minerals to Earth, space mining might best be applied as what is called “in situ resource utilization," where materials are found. extracted, processed, and used right at the site. Mined materials would be used for constructing and maintaining space stations or human settlements in near and deep space. Even so, interplanetary mining remains an expensive proposition. Only space-faring nations with the incentive and economic means could plan such ventures.

MINING LANDFILLS

You are finished with an electronic device that no longer works and is too costly to repair. Everything we use has a life expectancy—the time when it becomes obsolete, it no longer performs its intended function, or it isn't needed anymore. The item enters the waste stream: the flow of waste from its point of origin through its treatment to its disposal. What we toss out may end up in a sanitary landfill. waste incinerator, recycling center, or open-air dump.

According to the U.S. Environmental Protection Agency, for every million cell phones recycled, we recover 35,274 pounds of copper, 772 pounds of silver, 75 pounds of gold and 33 pounds of palladium. Recovering these metals saves energy and reduces the extraction of raw metals from the earth.

Many cities and towns have recycling programs. Most people are familiar with curbside recycling—we put recyclable household items (typically paper, plastics, glass, and aluminum) in a bin and take them to the curb, and municipal sanitation workers haul them to a recycling facility for sorting and distribution. Some communities have recycling centers where citizens drop off their recyclables. Once sorted and separated into different categories, the recyclables can be used to make new products.

Not all recycling centers accept electronic waste. Before you decide to throw out any electronic devices, check the municipal policy in your area. More and more centers now recycle electronics, from cell phones and laptops to TVs and other electronic devices. After sorting, the devices are dismantled and processed. Many of them contain contaminants such as lead, cadmium, and beryllium, which require special handling and disposal or recycling. Many metals, such as gold, silver, platinum, palladium, copper, tin, and zinc, can be recovered in recycling Glass and plastics also are recovered and recycled.

These recycled materials-no longer destined for landfills or incinerators—are recovered and used to create new products. Garden furniture, license plate frames, nonfood containers, replacement auto parts, art, and jewelry are among the many types of goods produced from recycled materials. Rechargeable batteries are recycled into other rechargeable battery products.

Did you know?

Iron, nickel, platinum, and cobalt are among the valuable elements that may be mined from asteroids or other cosmic bodies.

RECYCLING METALS

Most metals remain usable even after the products that use them have reached the end of their lifespan. Recycling metals saves the energy that is used to separate them from their ores. Also, the hauling of the recycled objects is usually shorter than from distant mined sources, further saving energy and the materials used in mining.

Worldwide demand for metals grows steadily at 1 to 3 percent annually. Even this apparently slow growth rate means additions must continually be made to the metal supply. New supplies come from new mine developments, expansions of existing operations, increased recycling, or all three.

Typically called scrap metal, recycled metal is categorized as either new or old scrap. New scrap comes from pre-consumer sources generated from the manufacturing of different products. Some gold, for example, is wasted unintentionally in the production of jewelry. The unused waste gold still has value, so the jewelry maker sells it to a scrap dealer. That way the unused gold is reintroduced into the jewelry-making business.

Old scrap comes from post-consumer supplies generated when an item has reached the end

of its usefulness. Cast-off jewelry, dental gold (gold teeth), and the gold components of

unwanted electronics are good examples of old-scrap gold. Copper is another commonly

recycled metal. A third or more of annual consumption comes from recycled scrap copper.

Other metals typically recycled at scrap yards include aluminum, brass, lead, silver, platinum,

iron, steel, and zinc. Most of these are recycled by manufacturers as new scrap. Much of the

old scrap is rescued from the waste stream and recycled by individuals committed to

salvaging such materials.

Recycling one aluminum can saves enough

energy to run a TV for three hours.

Sanitary landfills will probably be one source of minerals in the future. Metals and other

materials could be extracted from them, processed, and refined for reuse.

"RECYCLING" LANDFILLS

Except for the items that people conscientiously recycle and reuse, the vast majority of material entering the waste stream is picked up as municipal waste and placed in sanitary landfills. Waste in landfills is buried between layers of earth and isolated from the environment until it breaks down biologically, chemically, and physically.

Mining municipal landfills will require special skills and techniques to protect air, water, and soil from contamination. Care will be needed to restore or reclaim the sites for uses such as farming, forestry, recreation (golf courses, public parks, zoos, ball fields, etc.), or industrial parks for factories and other businesses.

Most of the consumer waste in landfills still has value. How could we recycle everything? Organics (substances of plant or animal origin) could serve as compost and be used as fuel. Solids such as plastics could become fuels or the basis for new products. Glass could be recycled for new glass or energy-saving insulation. One innovation is to use glass fibers with cement to form a stronger type of concrete.

We are able to account for about 85 percent of all the gold ever mined. About 15 percent is lost, mainly in electronics because the amount of gold in each device is too tiny to be recovered economically. The rest of the world's mined gold is held as heirloom jewelry, coins, and gold bullion (bars or ingots).

HEALTH & SAFETY IN MINES

At one time, mining was the most dangerous occupation in the United States. Making mines healthier and safer places is the responsibility of everyone involved—mine owners and workers, and federal and state governments. Improvements in mining engineering, education and training, government regulation, and industry leadership and decreasing community tolerance of mining incidents has led to a significant reduction in mining incidents and disasters.

Today, mining is among the safest industries in the United States as measured by nonfatal injury rates.

Operating a healthy and safe mine requires planning and active participation of all workers, from senior managers to miners. Mining companies understand that safety is a moral obligation necessary to minimize losses. Safety and health laws and regulations cover all facets of mining: planning, operations, maintenance, equipment, training, blasting, air quality, emergency response, etc. The U.S. Mine Safety and Health Administration and state agencies enforce mine health and safety laws and regulations.

The industry strives continually to improve safety. Many companies working with the National Mining Association have launched the CORESafety program to do just that. It plans to optimize mine safety by improving mine engineering work processes, and working conditions.

TOOLS FOR MINE AND HEALTH SAFETY

It is difficult to eliminate all risk from mining, so the focus is on managing risk at an acceptable level—for miners, management, government, and society. Some tools and techniques used in American mines to this end include hazard identification and risk assessment, personal protective equipment, environmental monitoring, and the introduction of automation for mining equipment.

Hazard Identification and Risk Assessment

"Being prepared” in mining means to anticipate and understand the risks in the mine. What is the likelihood that something will go wrong, and what is likely to happen if it does? Examples include the potential for gas or dust explosion in underground coal mines, mine wall collapse, fire, and mobile equipment striking a miner.

Personal Protective Equipment

Miners wear personal protective equipment to guard against injury. A hard hat protects the head; safety

glasses protect eyes, earplugs or ear-muffs minimize exposure to noise; gloves protect hands; and hard-toed

boots minimize the risk of foot injury from impact, slip trip, pinch heat and cold, etc. Where needed,

respirators protect against inhaling harmful dust, fumes, or gases.

Experts believe it is more effective to eliminate hazards where they occur. An example is using roof bolts to prevent roof fall accidents by holding up an underground mine roof. Steel rods, 4 to 16 feet long, anchor the roof rock in place. Ventilation systems help ensure air quality. When coal rock releases flammable methane gas, ventilation dilutes its concentration. Large fans on the surface and auxiliary fans inside the mine provide ventilation throughout underground tunnels and shafts to accomplish this.

Underground miners use a "self-rescue device" for protection from carbon monoxide gas and when escaping from smoke and toxic gases in case of fire or explosion.

Environmental Monitoring Technology

Different instruments, often handheld devices, detect harmful and flammable gases, dust, fumes, noise, or radiation, and ensure that adequate oxygen is present. Some monitor many gases at the same time. Others measure airflow in the ventilation system.

Instruments may be stationary or attached to mobile equipment. They measure environmental factors—such as carbon monoxide levels—in the mine, relying on telemetry (wireless communication) to send data to central control stations. Computers monitor ventilation fans in underground mines. Other devices track the position of miners so that mobile equipment doesn't run into them.

Detection systems warn miners of any developing fire. Alarms announce the need to take action. It may mean to evacuate the mine or, in an underground mine, to seek shelter in a refuge chamber. GPS networks help surface mines pinpoint equipment and help isolate hazards as they occur.

Remote Control and Automation

Computer technology has radically improved mine safety and health. Many mining

machines are remotely controlled to keep the miner from exposure to moving parts,

dust, noise, unstable ground, etc. The introduction of robotics is helping miners reduce

exposure to unnecessary risks. Some surface mines now use haul trucks that run

without a driver, using satellite navigation and robotics.

SAFETY ABANDONED MINES - KEEP OUT!

Mines are not like caverns open to the public for tours and recreation. Every year,

dozens of people are injured or killed in accidents on mine property. Active mines are

dangerous places even for highly trained workers and are regularly inspected for

hazardous conditions, unlike abandoned mines. These are not inspected and probably not ventilated, which means toxic or explosive gases may be present. Tripping and falling is common in abandoned mines—they are unlit and have no guardrails.

Quarry ponds, too, are dangerous. Diving into them is extremely risky because pond depth can vary greatly and abruptly. Riding dirt bikes and quads (four-wheelers) or otherwise trespassing on mine property is dangerous and illegal. High walls or steep cliffs may not be well marked

Mine rescue work uses a track-mounted robot to explore mines, reducing the need to send workers into potentially dangerous conditions. Automation and robotics will increasingly be used as people mine deeper deposits less accessible to miners, such as very thin deposits.

STAY OUT - STAY ALIVE!

Every year, dozens of people are injured or killed at active and abandoned mine sites. Every single one of these tragedies could have been avoided. The goal of this nationwide effort - called Stay Out - Stay Alive is to educate the public, particularly young people, about the dangers of abandoned and active mines.

Water-filled quarries and pits hide rock ledges, old

machinery and other hazards. The water can be

deceptively deep and dangerously cold. Steep,

slippery walls make exiting the water difficult. Hills of

loose material can easily collapse on an unsuspecting

biker or climber. Vertical shafts can be hundreds of

feet deep and may be completely unprotected, or hidden by vegetation.

Even so dozens of people are injured or killed while exploring or playing on mine property every year. The men and women employed in our nation's mines are trained to work in a safe manner. For trespassers, hazards are not always apparent.

For example:

Water-filled quarries can not only hide rock ledges but can also contain dangerous electric currents that become deadly under water.
Abandoned mine shafts that may seem fun to explore can unexpectedly collapse.

It is more important than ever to remind people to stay out of abandoned or active mine sites like quarries and pits – and stay alive.

Stay Out Stay Alive MSHAnet 940x590b-01.png

PROTECTING THE MARINE ENVIRONMENT

CAREERS IN MINING

When most people think about what a miner does, the first image that springs to mind is the miner heading underground with a headlamp, hardhat, simple tools, and a lunch pail. Or you may think about the shovel operator, haul-truck driver, or someone working a bulldozer or front-end loader. These images have triggered the imaginations of artists and writers who have passed them down to us over time.

A career in the mining industry includes many more occupations than these. The cycle of developing mineral resources has many parts, and all offer interesting, well-paying career opportunities. Mine workers take satisfaction in knowing they provide essential minerals and fuels that benefit society. Discovering and providing the minerals that increase our standard of living, minimizing environmental impacts, and contributing to a safe work situation are all benefits of a mining career. A mining career offers the prospect of travel, the challenge of working with advanced technology, and the opportunity for career advancement with increased responsibilities.

This illustration shows the sequence of events in mining and related careers.

MINING PERSONNEL

Some positions in mining are paid hourly. People working in the mine itself are mostly equipment operators. Those working at a surface mine include drillers and blasters, dragline, shovel, and excavator operators; front-end loader and bulldozer operators; haul-truck drivers, and support personnel. In an underground mine, workers operate cutting machines, shuttle cars, roof bolters, scoops, longwall shearers, jumbo drills, loaders, haul trucks, belt conveyors, trains, and other mobile equipment.

An operating mine might be in a remote location, along with the operations office and any connected processing plant. The division offices and company headquarters, however, or technical support are generally located in a large town or city.

The workers at a processing plant operate equipment for crushing and screening; physical and chemical procedures, especially in metal mines; haulage and mobile equipment; lab work; mapping and surveying; and other tasks. These are supported by software specialists, mechanics, welders, machinists, electricians, general laborers, and equipment manufacturers.

TECHNICAL PERSONNEL

The minimum educational requirement for technical workers typically is a high school diploma. An associate degree or trade school education will help the worker meet requirements for positions of greater responsibility and higher pay. An example is the electrical certification required for an underground electrician, who is paid more than a typical laborer in a coal mine. Underground professionals tend to earn more than their counterparts in surface mining. Many trade skills are obtained through programs provided by the mining company in combination with on-the-job training or community colleges.

PROFESSIONAL PERSONNEL

Many different kinds of professionals are needed to explore for minerals and to mine them; to plan new operations or to manage a mine. Mining professionals include geologists, mining and geological engineers, metallurgists, civil engineers, mine managers, and environmental specialists. These positions require a college degree, and in some cases, graduate degrees. Professional personnel evaluate the mineral or ore deposit for its economic potential. They create mining plans based on those evaluations. Scientists and engineers work together to plan and build the processing plant(s) needed to treat the ore or rocks after they are hauled out of the mine.

It takes many thousands of people to mine all the minerals and fuels we rely on and use. Mining provides above average income to miners, pays taxes to local, state, and federal governments, and often works with local communities to improve the quality of life for its neighbors.

CAREERS SUPPORTING THE MINING INDUSTRY

Equipment manufacturers and service companies support the mining industry, too. A wide variety of products is delivered to mines, ranging from office supplies to explosives, to heavy equipment Service companies may provide security for the mine site; workers for short-term maintenance positions such as welders, mechanics, and electricians, and consulting engineers for almost every aspect of mining and processing. There are careers in regulating the mining industry on local, state, or federal levels. These include health and safety inspectors, reclamation and water quality technicians and inspectors, and environmental quality experts.

Herbert Clark Hoover (1874-1964), was a mining engineer and scholar before he became the 31 st president of the United States (1929-1933). His mining career began in 1897, in the gold fields of Western Australia. He later traveled to the Far East, where he worked for the Chinese Bureau of Mines as chief engineer and then as general manager of the Chinese Engineering and Mining Corporation. Hoover became an independent mining consultant in 1908, setting up offices worldwide. His mining ventures brought him wealth, but he was also famous as a published scholar.

John Llewellyn Lewis (1880-1969) was an American leader of organized

labor. From 1920 to 1960 he served as president of the United Mine

Workers of America. He also worked to establish the Congress of

Industrial Organizations, organizing millions of industrial workers in

the 1930s. Under his leadership, coal miners won high wages, an

eight-hour work day, good pensions, and good medical benefits.

The creation of the UMWA Welfare and Retirement Fund was perhaps

his greatest legacy. The fund helped establish eight regional hospitals

and many medical clinics in Appalachian coal country. In 1964,

President Lyndon Johnson awarded Lewis the Presidential Medal of Freedom, the highest civilian decoration in the country, recognizing his many contributions to the labor movement.