NOTE: In 1996, the U.S. Congress directed that the 

U.S. Bureau of Mines be abolished. Health and safety 

research at the research centers at Pittsburgh, PA, and 

Spokane, WA, was permanently assigned to the 

National Institute for Occupational Safety and Health 

(NIOSH). NIOSH is part of the Centers for Disease 

Control and Prevention within the U.S. Department of 

Health and Human Services. 

Cover photos: (Top) Extracting coal with a remote-operated continuous mining machine in an 

underground room-and-pillar mine in West Virginia. (Photo by Christopher C. Jobes, 

USBM.) 

(Bottom) Loading salt after a blast in a Louisiana salt mine. (Photo by Gregory M. 

Molinda, USBM.) 
Page 

Introduction .................................. 1 

Mining methods ............................... 5 

Coalmining ................................ 6 

Room-and-pillar mining ....................... 7 

Longwall mining ........................... 10 

Surface mining ............................ 12 

Metal/nonmetal mining ......................... 14 

Room-and-pillar mining ....................... 14 

Sublevel caving ............................ 15 

Block caving .............................. 18 

Cut-and-fill mining .......................... 19 

Sublevel stoping ........................... 21 

Borehole mining ........................... 22 

Surface mining ............................ 25 

Mine closure .................................. 28 

In conclusion ................................. 30 

About the U.S. Bureau of Mines ...................... 31 
UNIT OF MEASURE ABBREVIATIONS 

USED IN THIS REPORT 

cm centimeter 

ft foot 

ft3 cubic foot 

in inch 

km kilometer 

m meter 

m3 cubic meter 

mile 

short ton 

ton (metric) 
M INING IS THE BRANCH OF INDUSTRY 

involving the exploration and removal of minerals from the earth (figure I). Mining is one of the 

oldest and most important endeavors of humankind, 

because it provides the raw ingredients for most of the 

material world around us and, like agriculture, is the 

lifeblood of civilization. The main objective of any 

type of mining is to remove the valuable material 

economically and safely with minimum damage to 

the surrounding environment. 

The Earth has many natural resources on which we 

depend that must be mined. Coal, oil, gas, and 

other mineral fuels are used for heating, electricity, 

and numerous industrial processes. Nonfuel minerals such as iron ore, precious metals, and industrial metals, and nonmetallic materials like sodium 

and potassium are used in chemical and agricultural applications. Even crushed stone used in road 

building and other construction projects must be 

mined. Mining affects our standard of living and 

impacts almost everything we do. A myriad of 

items that we use in our homes and offices and for 

transportation, communications, and national defense all require minerals (figure 2). For example, 

more than 30 different minerals are needed to make 

a television or telephone! Table 1 lists several commonly mined materials and some of the end uses in 

our daily lives. 
Figure 1 .-Typical arrangement of mine development. (O Used with kind permission of Atlas Copco A B.) 
Figure 2.-A diversity of minerals are used to produce a multitude of everyday products. 

Table 1.--Commonly mined materials and end uses 

Mined material End uses 

Coal ................. Generating electricity, making iron and steel, manufacturing chemicals and other products. 

Sand and gravel ....... Building roads, homes, schools, offices, and factories. I 

Iron ore .............. Steel products (kitchen utensils, automobiles, ships, buildings). 

Aluminum ore 

(bauxite) ............ Military aircraft, naval vessels, pots and pans, beverage cans. 

Copper ore ........... Electrical motors, generators, communications equipment, wiring. 

Silver ore ............. Electric and electronics circuitry, coins, jewelry, photographic film. 

Gold ore ............. Jewelry, satellites, sophisticated electronic circuits. I 

Zinc ................. Diecasting, galvanizing brass and bronze, protective coatings on 

steel, chemical compounds in rubber and paints. 

Lead ................ Batteries, solder, electronic components. 

Clay ................. Bricks, paper, paint, glass, pottery, linoleum, concrete, wallboard, 

spackling, pencils, microwavable containers, vegetable oil. 

Gypsum .............. Concrete, wallboard, spackling, caulking, potting soil. 

Phosphate ............ Plant fertilizers. 

Salt ................. Cooking, drinking water, plastics, highway de-icing, detergents. 
Minerals are vital to any industrialized civilization. 

The United States uses more than 3.6 billion t 

(4 billion st) of new mineral materials yearly, or 

about 18,000 kg (40,000 lb) per person, with about 

half constituting mineral fuels and the other half 

being metals and nonmetals. Stable and economic 

domestic mining, mineral, metal, and mineral reclamation industries are essential to our economy 

and our national defense. The value of processed 

(nonfuel) materials of mineral origin produced in 

the United States totaled approximately $360 billion in 1994. During the lifetime of the average 

American, he or she will use- 

* 1,600 kg (3,600 1b) of aluminum 

360 kg (800 lb) of zinc 

11,300 kg (25,000 lb) of clay 

25,400 kg (56,000 lb) of steel 

360 kg (800 lb) of lead 

680 kg (1,500 lb) of copper 

12,200 kg (27,000 lb) of salt 

More than 226,000 kg (500,000 1b) of coal 

More than 453,000 kg (1 million lb) of stone, 

sand, gravel, and cement. 

As you can see, the mineral extractive industries 

play a critical role in the vitality of our Nation's 

economy, in our standard of living, and in our 

personal lives. 
T HE METHOD USED TO MINE A SPECIFIC 

commodity depends chiefly on the shape and 

location of the deposit. In many instances, the deposit 

is relatively flat and continuous over a large area. 

Examples of flat, or tabular, deposits are coal, potash, 

salt, and oil shale. These deposits are found in beds, 

or seams, between layers of rock. The material above 

the seam is called the overburden; the seam itself may 

vary in thickness from several centimeters to more 

than 30 m (100 ft) (figure 3). 

Mining of deposits that are not flat and continuous, 

however, requires one of a variety of methods to 

extract these deposits either from the surface or underground. The method used depends on the geometry, size, and altitude of the deposit. 

Some of the minerals produced, such as coal and salt, 

are ready to use right after they have been mined. It 

may be necessary to wash or treat these commodities 

in different ways to enhance their quality, but their 

properties remain essentially unchanged. 

Metals, conversely, usually 

occur in nature as ores, i.e., 

combined with other materials. This means that they must 

be treated, usually with chemicals or heat, to separate the 

desired metal from its host material. These processing techniques can be very complex 

and expensive, but they are 

necessary to recover the metal 

of interest. Figure 3.-Cross-section of a mineral deposit. 

Surface 

//>. .... ... ... .;? ....... . . . . : . . ... . . .... ....... . . .' . . ,.. . . 1 : . . .: ..... 

... 
COAL MINING 

Coal was formed from plant remains deposited millions of years ago. There are several types of coals, 

and their characteristics depend largely on how many 

million of years it took them to form and the levels of 

heat and pressure to which they were exposed. Coal 

deposits range from a soft peat (a kind of "precoal") 

to a hard, shiny anthracite. Most of the coal mined in 

the United States is a midrange bituminous coal. 

Coal is our most abundant fossil fuel. It is used to heat 

homes and offices, power electric plants, and supply 

energy to many industries. When heated in the absence of air (carbonization), coal produces coke, 

which is used to manufacture iron into steel. Coal is 

also used to produce synthetic products that can be 

substituted for less abundant natural gas and fuel oil 

or for the many plastic items we use daily. 

Coal and other tabular deposits can be mined underground by various tunneling methods or from the 

surface by simply removing the coveringrocks, called 

overburden. Underground mining is usually done 

when the deposit is more than 45 m (150 ft) below the 

surface, in which case the overburden is simply too 

thick and expensive to remove. Access to deep coal 

seams is achieved either by shafts or slopes driven 

down to the seam or through drifts driven directly 

into the coalbed if it is exposed on a hillside. 

Many years ago, underground coal was mined by 

pick and shovel and hauled out in carts by people, 

sometimes even by children. Later, horses and mules 
were used to drag the carts 

(figure 4). Today, powerful machines help miners 

to cut and transport the 

coal out of the mine to 

preparation plants, where 

it is cleaned, sorted, and Figure 4.-Horses and mules were used to 

readied for industrial use. haul out underground coal in carts years ago. 

Coal is usuallyrecovered from underground mines in 

either of two methods: room-and-pillar mining or 

longwall mining. 

Room-and-Pillar Mining 

The room-and-pillar mining method entails the excavation of a series of "rooms" into the coalbed, leaving 

"pillars" or columns of coal to help support the mine 

roof (figure 5). In conventional room-and-pillar mining, the coal is broken up by explosives, loaded onto 

a vehicle by a mechanized loading machine, and 

transported from the production area by shuttle cars 

(figure 6). 

Continuous mining is a type of room-and-pillar 

method in which a powerful machine called a continuous miner (figure 7) cuts and loads the coal into 

shuttle cars or onto conveyor belts that remove the 

coal from the mine. Bolts installed in the mine roof 

(figure 8) help to ensure that all of the layers of roof 

are consolidated and properly supported (figure 9)) 

thereby preventing dangerous roof cave-ins that 

could injure or kill the underground miners. 
Figure 5.-Room-and-pillar mining. (0 Used with kind permission of 

Atlas Copco A B.) 

Figure 6.-Shuttle car used to transport coal from the 

production area. 
I'" 1 

Figure 7.-Continuous mining machine for cutting coal. 

Figure 8.-Bolts installed in the mine Figure 9.-Diagram of roof bolts suproof help to prevent roof falls, thereby pre- porting the mine roof. 

venting fatalities and injuries to underground miners. 
Longwall Mining 

The second underground coal mining system is 

longwall mining. Originally developed in Europe, 

longwall mining is now also popular in the United 

States because of the greater safety and efficiency it 

affords. In this method, a rotating shear on the mining machine (figure 10) shaves from blocks or panels 

of coal in a back-and-forth motion, similar to that of a 

meat slicer, and dumps the broken coal onto a conveyor belt that extends across the longwall (figure 11). 

Perhaps the most attractive feature of modern 

longwall mining is the shielded roof supports that 

advance with the mining operation, providing maximum protection to the miners (figure 12). As the 

mining machine advances, the roof behind it caves in. 

This collapsed area is called the gob (figure 11). 

Figure 10.-Longwall shearer cutting coal. 

10 
Figure 11 .-Plan view of longwall mining. 

Figure 1 2.-Longwall roof supports. 
Surface Mining 

Surface, or open pit, mining of coal is done where the 

overburden is relatively shallow. Large earth-moving equipment, draglines (figure 13), or shovels are 

used to remove the fractured overburden from the 

coal (figure 14). The coal is then typically broken up 

by blasting it with explosives. The coal is loaded into 

special haulage trucks (figure 15) that carry it away to 

preparation plants, where the rock, soil, and impurities, such as sulfur, are removed. Federal laws require 

that the resulting open pits be filled, graded to about 

their original contour, and planted for agricultural or 

recreational purposes so that the natural environment is protected and our Nation is kept beautiful. 

Figure 13.-Dragline used to remove overburden. 
Blast holes Explosives fracture 

are drilled overburden Dragline removes overburden 

Figure 14.--Overburden is fractured with explosives, then removed 

with a dragline or large excavating shovel. 

Figure 15.-Large haulage trucks are used to transport coal from the mine. 

13 
METAL/NONMETAL MINING 

Most metallic and nonmetallic deposits are found in 

a variety of shapes of varying size and mineral content, properties that dictate the economic feasibility of 

mining these commodities in the first place and that 

also determine the most appropriate mining method. 

The highest-volume commodity produced by the 

U.S. minerals industry is crushed stone. An estimated 1.2 billion t (1.3 billion st) of crushed stone was 

produced in the United States in 1994 valued at approximately $6.4 billion. 

Room-and-Pillar Mining 

A wide range of methods can be used to mine such 

deposits. Underground room-and-pillar mining 

methods for many metal/ nonmetal deposits differ 

from those of coal and other softer mineral deposits. 

These differences primarily involve equipment used, 

method of breaking up the ore, and ways of removing 

the ore from the mine. 

The ore-breaking system used in these instances differs from coal breakage systems because of hardness. 

Whereas coal can be cut continuously with a shearer 

or continuous mining machine, almost all metal 

mines use pneumatic or hydraulic percussion drills of 

the jackhammer type to drill small-diameter holes 

(6.4 cm by 3 m (2.5 in by 10 ft)). These holes are filled 

with explosives, which are then detonated. Some 

mines may use larger holes (15 cm by 12 m (6 in by 

40 ft)) if the physical limits of the ore allow it. The 

holes in a limited section are blasted, the area is then 

made safe, and ore removal can begin. 
Figure 16.-Load-haul-dump unit for ore transfer. 

Front-end loaders or load-haul-dump machines (figure 16) remove the broken ore from where it was 

blasted. Normally, a load-haul-dump unit will not 

haul ore out of the mine, but rather transfers the ore 

to a truck. In addition to diesel vehicle haulage, a conveyor belt or rail may be used for hauling ore to a 

shaft, which then hoists the ore to the surface. On rare 

occasions when a deposit is shallow, ore can be carried directly to the surface processing facilities. 

Sublevel Caving 

Caving methods require that the ground surface be 

permanently available for closure and isolation and 

that the rock above and around the ore body be weak 

so that it will break into a fractured mass and the 

ore will fracture into small pieces. Sublevel caving 

(figure 17) applies best to wide, vertically oriented, 

vein-type ore bodies (figure 18). This mining method 

entails a ramp and borehole from which sublevels, 

spaced 6 to 12 m (20 to 40 ft) apart vertically, extend 
Figure 17.-Sublevel caving mining method. (O Used with kind permission 

of Atlas Copco AB.) 
through the ore body. Each 

main level, which is 60 to 120 m 

(200 to 400 ft) apart vertically, 

may intersect one or more of 

the boreholes with chutes to 

transfer the broken ore to rail 

or other haulage systems out 

of the mine. Each sublevel ad- Figure 18.-Vein-type deposit. 

vances sequentially by drilling and blasting, with supports added as necessary 

until the sublevel has penetrated though the ore 

body. 

Reversing the process, either the supports are gradually removed in 0.6- or 1.2-m (2- or 4-ft) segments or 

the ore overhead is drilled and blasted in the same 

pattern. The ore falls, and the load-haul-dump unit 

hauls it to the borehole. As the ore is removed, the 

rock above gradually falls. When this rock 

(called waste) appears, the operator removes additional supports or blasts in a retreat pattern, repeating 

the process until all ore on that sublevel is removed 

and the waste has filled the sublevel. Other sublevels 

are similarly activated in sequence. Gradually, the 

process progresses down the ore body while the surface subsides into the opening. The method does not 

apply to narrow veins that would cause hangup or 

dilution of the ore with waste or to flat-lying ore 

bodies where gravity cannot be used to cause the ore 

to break. 
Block Caving 

Large ore bodies of lower grade can be mined with 

the block caving method (figure 19), so called because 

mining occurs sequentially in segments or blocks 60 

to 150 m (200 to 500 ft) on a side in all three directions. 

A series of railroad tunnels is constructed under the 

Transport drift 

Figure 19.-Block caving mining method. (O Used with kind permission of 

Atlas Copco A B.) 

18 
ore to be mined. At approximately 30-m (100-ft) intervals along each tunnel in a checkerboard pattern, 

3- to 6-m (10- to 20-ft) diameter raises connect the rail 

tunnels with another series of cross drifts. In the cross 

drifts, scrapers (hoes pulled by a cable from an electric 

motor) pull the ore back to the raised areas to dump 

the ore in railroad cars. The ore falls down finger 

raises intersecting the cross drifts below. These raises 

are driven in many directions into the ore above, 

usually with four or more intersecting at one point in 

the cross drift. These raises act first as a place to blast 

the entire underside of the ore block, then later as a 

funnel to draw the blasted ore. The ore continues 

to fall from the bottom of the block as it is pulled from 

the raises, for it now has no foundation. No further 

entry can be made in the finger raises once the block 

begins to cave in. 

On extremely large ore bodies, many parallel and 

abutting blocks are mined, a process that can last 

several years. If the ore extends in depth, additional 

levels develop in the same manner below. Ore and 

waste that are separated may exceed 90,000 t (100,000 st) 

daily from such an operation. 

Cut-and-Fill Mining 

Some ore deposits are essentially tabular but irregular, with varying thickness, inclination, and strength. 

The cut-and-fill mining method (figure 20) provides 

adaptability to all of these variables. Its name is derived from the way the ore is mined. The ore is 

removed, or cut, from a small segment of the ore body 
Figure 20.-Cut-and-fill mining method. (O Used with kind permission of 

Atlas Copco A B.) 

(0.6 to 110 m3 (20 to 4,000 ft3)), then waste rock is 

placed back in the hollow for support. This process 

is repeated, advancing along a horizontal level 

through the ore body. 

After one level is mined and filled, the process is 

repeated in the ore body above the fill material. Most 

frequently today, the filling material comes from the 

processing plant in the form of fine sand and water 

called slurry or tailings, which is mixed with cement 

to form a stable fill. 

The cut-and-fill method provides a reasonably safe, 

versatile system for recovering ore that could not 

otherwise be mined. Throughout the world, hundreds of mines use this method in almost as many 

variations. However, the ore deposit must be of sufficiently high concentration and value to economically justify this approach. 
Sublevel Stoping 

Wide-vein deposits contained within competent 

waste rock and at vertical or steeply angled inclination permit use of a method called sublevel stoping 

(figure 21). This method can be likened to the month 

on the page of a calendar, with the top and bottom 

Figure 21 .-Sublevel stoping mining method. (O Used with kind 

permission of Atlas Copco AB.) 
edges representing the main haulage levels where all 

of the ore from above is removed. Each row of weeks 

on the calendar page represents sublevels started 

from the right-hand edge raise toward the left-hand 

edge raise widened to full-vein width. The sublevels 

starting at the bottom left day of the calendar page are 

drilled with long holes in a circle around the opening, 

then blasted in one large blast, removing a segment 

of rock 0.6 to 1.2 m (2 to 4 ft) along the sublevel. It 

would be like removing one day of the week from left 

to right, bottom to top of the calendar page, and 

dropping it to the bottom edge, where previously 

installed chutes funnel them to the train or load-hauldump unit for haulage to the shaft. 

The sublevel stoping method works only if the walls 

of the opening around the ore do not cave. The safety 

of this method relies on exposing personnel to a small 

tunnel opening that can be supported. Variations of 

the method include vertical crater retreat (figure 22) 

and blasthole mining. Large-tonnage production can 

be provided in veins 3 m (10 ft) to hundreds of meters 

wide with ingenuity in design and planning. 

Borehole Mining 

Some commodities, such as salt or phosphate, which are 

soluble in water, are mined through boreholes (figure 23). 

A borehole is drilled into the formation. A jet of water 

is then used to loosen the desired material, which is 

pumped to the surface with the water. Here, the salt is 

separated from the water, usually by evaporation. 

Materials like copper and precious metals can have 

the minerals dispersed. With in situ mining, a fluid 
Figure 22.-Vertical crater retreat mining method. (O Used with kind permission 

of Atlas Copco A B.) 
that will dissolve the ore is circulated through the 

deposit. The fluid, with the mineral in solution, is 

then pumped to the surface where the minerals are 

separated from the fluid, which is reused (figure 24). 

Figure 23.-Borehole mining method. 

Figure 24.-In situ mining operation. 

24 
Surface Mining 

Deposits that can be mined using surface mining 

techniques differ greatly in character. They may vary 

from small surface gold, sand, gravel, or stone to large 

metal sulfide or oxide deposits that are several kilometers wide and long and possibly 0.8 krn (0.5 mi) 

deep, but most readily mined from the surface. Other 

metallic deposits may fill cracks in the rocks, twist, or 

form large underground areas, but are so deep that 

they require shafts and tunnels to reach them. Even 

some relatively flat-lying deposits are so deep that 

they require shafts more than 3.2 krn (2 mi) deep to 

reach them. 

Today's surface mining methods in metal/nonmetal 

mines usually require removal of soil and/or useless 

rock before drilling and blasting the deposit in 

benches or stairsteps. Since few deposits are pure, 

waste rock may be removed to the waste pile by 

shovel and truck or front-end loader while ore is 

loaded into other vehicles to be taken to processing 

plants. 

Generally, surface mining includes (1) identification 

of the ore and waste rock, (2) removal of surface soil 

and debris, (3) drilling and blasting of ore and waste, 

(4) removal of ore to processing facilities and waste to 

the dump, and (5) reclamation and environmental 

rehabilitation. 
The first step, identification, must include as much as 

possible about the size, geometry, values, environment, water, strength, and physical qualities of the ore 

and waste in and around the ore body to be mined. 

This requires drilling holes that recover samples, 

making test pits and openings, and using geophysical 

methods involving waves, rays, or other systems to 

acquire information, Identification may take years at 

great costs, but without the information, the engineer 

cannot design a safe, economical plan to remove the 

desired material. 

The next four steps often proceed in sequence, with 

each process overlapping if possible. Surface soil and 

debris may be placed to one side for later reclamation 

and replanting. At the very least, such soil is removed 

and protected against erosion and environmental 

damage. Surface rain and drainage must also be controlled for the life of the mine and future environmental protection after mine shutdown. 

Although the stripped soil may uncover the rock, the 

remaining surface is often irregular and weathered, 

requiring leveling and removal by either bulldozing 

or drilling holes that are loaded with explosives and 

blasted. This initial work establishes the mining plan 

for haul roads, bench width and height, drilling, loading, and blasting of the ore body and the waste that is 

included in the ore and external to the ore body. 

Information gathered from exploration, as well as the 

initial excavation activities, help to develop the plan 

for appropriate bench height and width, slope of each 
segment of the pit, tonnage and value to be recovered 

each shift, and other parameters necessary for successful, orderly recovery of the ore body at maximum 

safety and economy. Gradually, the pit deepens, and 

problems of water encroachment, haulage road maintenance, pit slope, and increasing waste-to-ore ratio 

are resolved until a predetermined closure point is 

reached or economical changes occur that no longer 

make it profitable to mine. 
C LOSURE NORMALLY MEANS CESSATION OF 

all mining at a site. Of course, some temporary 

disruption to the environment is unavoidable when 

taking mii~erals from the ground and turning them 

into useful products. Mine closure, therefore, usually 

requires some environmental activities such as removal of hazards, recontouring, and planting where 

possible. 

Closure occurs when all scheduled reclamatiol~ plans 

have been completed and safety of the area is ensured. 

In fact, through comprehensive environmental planning, mining companies can now return mined land 

to the identical condition that existed before mining 

occurred (figure 25). Mining can thus be executed 

Figure 25.-Protecting the environment through reclamation is a 

vital part of mining. With modern mining technology, the land is left 

as close as possible to the way it was found before mining. 
with mindful concern for our health and respect for 

ecological needs. If plans consider future reactivation, Federal, State, and local regulations provide for 

protection of the public. 

The time to locate and define the mineral deposit, 

prepare and mine, and finally close the deposit can 

vary from 2 to more than 100 years. Capital costs to 

begin mining can range from $100,000 for a small 90-t 

(100-st) per day mine to $1 billion for a large 18,000-t 

(20,000-st) per day remote mine. Comparisons may 

be misleading because of diversity of location, physical situations, and products involved. However, in 

the free-world marketplace, profitability controlled 

by economics of costs and prices dictates whether and 

how long a deposit will be operated as a mine. 
M OST OF US TAKE FOR GRANTED THAT THE 

mining and processing of raw materials from 

the ground are the basic building blocks from which 

all technological advancements and products are 

made-products that we need and use in our everyday life, from the cars we drive to the planes we fly... 

from the chemicals used in medicines to the fertilizers 

we feed our crops ... from the multitude of appliances, 

tools, and machinery to, in general, all of the useful 

devices that humankind can imagine and fashion. 

Fossil fuels from the earth-coal, oil, natural gasprovide the energy to heat, cool, and light our homes, 

refrigerate and cook our food, power our factories, 

and transport ourselves and our products around the 

world. 

Yes, there are few times, if any, that we stop to consider the importance of mining and minerals. Yet 

the quality of our life, our national security, the stability of domestic and world economies, science, industry, and the arts are all based on the minerals we 

mine from the earth. No matter how complex or 

simple a finished product may be or how routine its 

use, it exists because of something found in the - 

ground that we can mix, mold, melt, cast, extrude, 

alloy, grind, stamp, or stretch into something useful. 

But first it must be mined! 
ABOUT THE 

HE MISSION OF THE U.S. BUREAU OF MINES 

Twsm, is to help ensure that the United States 

has an adequate, dependable supply of minerals and 

materials to meet its national security and economic 

needs at acceptable social, environmental, and economic costs. The USBM is engaged in all aspects of 

mining and minerals processing research-coal, 

metal, and nonmetal-as well as mineral data collection and analysis. The USBM research program has 

reached a high degree of maturity, with numerous 

techniques already in use or approaching the point 

where they can be applied by the industry. 

Nevertheless, changing mining conditions, such as 

deeper andlor thinner deposits with unstable formations, will continue to dictate the need for improvements in existing mining processes. Also, 

improvements in mine efficiency have increased the 

need for new or alternative methods to maintain current health and safety achievements. The USBM is 

committed to addressing these needs through new 

and radical approaches that will provide the information and technology necessary to improve mining 

health, safety, and efficiency while maintaining high 

environmental standards. 

For additional information, please contact theLaboratory Director 

NOSH Pittsburgh Research Laboratory 

626 Cochrans Mill Rd. 

P.O. Box 18070 

Pittsburgh, PA 15236-0070 

Phone: (4 12) 3 86-660 1 

Fax: (412)386-6614