A

Acid Rain
Acid rain forms when certain atmospheric gases (primarily carbon dioxide, sulfur dioxide, and nitrogen oxides) come in contact with water in the atmosphere or on the ground and are chemically converted to acidic substances. Oxidants play a major role in several of these acid-forming processes. Carbon dioxide dissolved in rain is converted to a weak acid (carbonic acid). Other gases, primarily oxides of sulfur and nitrogen, are converted to strong acids (sulfuric and nitric acids).
Active Ingredient
In any pesticide product, the component that kills, or otherwise controls, target pests. Pesticides are regulated primarily on the basis of active ingredients.
Afforestation
The act or process of establishing a forest, especially on land not previously forested.
Agricultural Waste
Poultry and livestock manure, and residual materials in liquid or solid form generated from the production and marketing of poultry, livestock, furbearing animals, and their products. Also includes grain, vegetable, and fruit harvest residue.
Air pollution
The existence in the air of substances in concentrations that are determined unacceptable to human health and the environment. Contaminants in the air we breathe come mainly from manufacturing industries, electric power plants, exhaust from automobiles, buses and trucks.
Air Quality Standards
The level of selected pollutants set by law that may not be exceeded in outside air. Used to determine the amount of pollutants that may be emitted by industry.
Asbestos
A mineral fiber that can pollute air or water and cause cancer or asbestosis when inhaled.
Assimilative Capacity
The ability of a natural body of water to receive wastewaters or toxic materials without harmful effects and without damage to aquatic life.
Atmosphere
The air surrounding the Earth, described as a series of layers of different characteristics. The atmosphere, composed mainly of nitrogen and oxygen with traces of carbon dioxide, water vapour and other gases, acts as a buffer between Earth and the sun. The layers, troposphere, stratosphere, mesosphere, thermosphere and the exosphere, vary around the globe and in response to seasonal changes.

B

Bactericide
A pesticide used to control or destroy bacteria, typically in the home, schools, or on hospital equipment.
Bioassay
A method of testing a material's effects on living organisms.
Biochemicals
Chemicals that are either naturally occurring or identical to naturally occurring substances. Examples include hormones, pheromones, and enzymes. Biochemicals function as pesticides through non-toxic, non-lethal modes of action, such as disrupting the mating pattern of insects, regulating growth, or acting as repellants. Biochemicals tend to be environmentally compatible and are thus important to Integrated Pest management programs.
Biodegradable
The ability of a substance to be broken down physically and/or chemically by microorganisms. For example, many chemicals, food scraps, cotton, wool, and paper are bio-degradable; plastics and polyester generally are not.
Biodiversity
The number and variety of different organisms in the ecological complexes in which they naturally occur. Organisms are organized at many levels, ranging from complete ecosystems to the biochemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, and genes that must be present for a healthy environment. A large number of species must characterize the food chain, representing multiple predator-prey relationships.
Biological pesticides
Certain microorganisms, including bacteria, fungi, viruses, and protozoa that are effective in controlling target pests. These agents usually do not have toxic effects on animals and people and do not leave toxic or persistent chemical residues in the environment.
Biome
Well-defined terrestrial environment (e.g. desert, tundra, or tropical forest). The complex of living organisms found in an ecological region.
Bioremediation
The use of living organisms (e.g., bacteria) to clean up oil spills or remove other pollutants from soil, water, and wastewater.
Biosphere
Part of the Earth system in which life can exist, between the outer portion of the geosphere and the inner portion of the atmosphere.
Biota
All living organisms in a given area.

C

Carcinogenic or Carcinogen
Capable of causing cancer. A suspected carcinogen is a substance that may cause cancer in humans or animals but for which the evidence is not conclusive.
Chlorination
Adding chlorine to water or wastewater, generally for the purpose of disinfection, but frequently for accomplishing other biological or chemical results. Chlorine also is used almost universally in manufacturing processes, particularly for the plastics industry.
Chlorofluorocarbons (CFCs)
A family of chemicals commonly used in air conditioners and refrigerators as coolants and also as solvents and aerosol propellants. CFCs drift into the upper atmosphere where their chlorine components destroy ozone. CFCs are thought to be a major cause of the ozone hole over Antarctica.
Chronic Effect
An adverse effect on any living organism in which symptoms develop slowly over a long period of time or recur frequently.
Clear Cut
Harvesting all the trees in one area at one time, a practice that destroys vital habitat and biodiversity and encourages rainfall or snowmelt runoff, erosion, sedimentation of streams and lakes, and flooding.
Cloning
In biotechnology, obtaining a group of genetically identical cells from a single cell; making identical copies of a gene.
Clouds
A visible mass of liquid droplets suspended in the atmosphere above Earth's surface. Clouds form in areas where air rises and cools. The condensing water vapour forms small droplets of water (0.012 mm) that, when combined with billions of other droplets, form clouds. Clouds can form along warm and cold fronts, where air flows up the side of the mountain and cools as it rises higher into the atmosphere, and when warm air blows over a colder surface, such as a cool body of water.
Climate Change
This term is commonly used interchangeably with "global warming" and "the greenhouse effect," but is a more descriptive term. Climate change refers to the buildup of man-made gases in the atmosphere that trap the suns heat, causing changes in weather patterns on a global scale. The effects include changes in rainfall patterns, sea level rise, potential droughts, habitat loss, and heat stress. The greenhouse gases of most concern are carbon dioxide, methane, and nitrous oxides. If these gases in our atmosphere double, the earth could warm up by 1.5 to 4.5 degrees by the year 2050, with changes in global precipitation having the greatest consequences.
Commercial Waste
All solid waste from businesses. This category includes, but is not limited to, solid waste originating in stores, markets, office buildings, restaurants, shopping centers, and theaters.
Community Relations
Two-way communications with the public to foster understanding of conservation programs and actions and to increase citizen input into conservation decisions.
Compost
Decomposed organic material that is produced when bacteria in soil break down garbage and biodegradable trash, making organic fertilizer. Making compost requires turning and mixing and exposing the materials to air. Gardeners and farmers use compost for soil enrichment.
Concentration
The relative amount of a substance mixed with another substance. An example is five parts per million of carbon monoxide in air or 1 milligram/liter of iron in water.
Condensation
Change of a substance to a denser form, such as gas to a liquid. The opposite of evaporation.
Construction and Demolition Waste
Waste building materials, dredging materials, tree stumps, and rubble resulting from construction, remodeling, repair, and demolition operations on houses, commercial buildings and other structures, and pavements. May contain lead, asbestos, or other hazardous materials.
Convection
The rising of warm air and the sinking of cool air. When a layer of air receives enough heat from the Earth's surface, it expands and moves upward. Colder, heavier air flows under it which is then warmed, expands and rises. The warm rising air cools as it reaches higher, cooler regions of the atmosphere and begins to sink. Convection causes local breezes, winds, and thunderstorms.
Corrosive
A substance that eats or wears away materials gradually by chemical action.
Conservation
Preserving and renewing natural resources to assure their highest economic or social benefit over the longest period of time. Clean rivers and lakes, wilderness areas, a diverse wildlife population, healthy soil, and clean air are natural resources worth conserving for future generations.

D

Deep Well Injection
A process by which waste fluids are injected deep below the surface of the earth.
Discharge
The release of any waste into the environment from a point source. Usually refers to the release of a liquid waste into a body of water through an outlet such as a pipe, but also refers to air emissions.
Disposal
The discharge, deposit, injection, dumping, spilling, leaking, or placing of any solid waste or hazardous waste into the environment (land, surface water, ground water, and air).
Disposal Facility
A landfill, incinerator, or other facility which receives waste for disposal. The facility may have one or many disposal methods available for use. Does not include wastewater treatment.
Dissolved Oxygen (DO)
Oxygen that is freely available in water to sustain the lives of fish and other aquatic organisms.
Dose
In terms of monitoring exposure levels, the amount of a toxic substance taken into the body over a given period of time.
Dose Response
How an organism's response to a toxic substance changes as its overall exposure to the substance changes. For example, a small dose of carbon monoxide may cause drowsiness; a large dose can be fatal.
Dump
A land site where wastes are discarded in a disorderly or haphazard fashion without regard to protecting the environment. Uncontrolled dumping is an indiscriminate and illegal form of waste disposal. Problems associated with dumps include multiplication of disease-carrying organisms and pests, fires, air and water pollution, unsightliness, loss of habitat, and personal injury.

E

Earth system
The Earth regarded as a unified system of interacting components, including geosphere (land), atmosphere (air), hydrosphere (water and ice), and biosphere (life).
Ecology
The study of the relationships between all living organisms and the environment, especially the totality or pattern of interactions; a view that includes all plant and animal species and their unique contributions to a particular habitat.
Ecosystem
The interacting synergism of all living organisms in a particular environment; every plant, insect, aquatic animal, bird, or land species that forms a complex web of interdependency. An action taken at any level in the food chain, use of a pesticide for example, has a potential domino effect on every other occupant of that system.
El Niño
A warming of the surface waters of the eastern equatorial Pacific that occurs at irregular intervals of 2-7 years, usually lasting 1-2 years. Along the west coast of South America, southerly winds promote the upwelling of cold, nutrient-rich water that sustains large fish populations, that sustain abundant sea birds, whose droppings support the fertilizer industry. Near the end of each calendar year, a warm current of nutrient-poor tropical water replaces the cold, nutrient-rich surface water.
Emergency Broadcasting System (EBS)
Used to inform the public about an emergency and the protective actions to take. The EBS is a service of local radio and television stations, activated as needed and approved by a local emergency management agency.
Emission
The release or discharge of a substance into the environment. Generally refers to the release of gases or particulates into the air.
Emission Standards
Government standards that establish limits on discharges of pollutants into the environment (usually in reference to air).
Endangered Species
Animals, plants, birds, fish, or other living organisms threatened with extinction by man-made or natural changes in the environment.
Energy Recovery
To capture energy from waste through any of a variety of processes (e.g., burning). Many new technology incinerators are waste-to-energy recovery units.
Environmental Equity
Equal protection from environmental hazards for individuals, groups, or communities regardless of race, ethnicity, or economic status.
Environmental Justice
The fair treatment of people of all races, cultures, incomes, and educational levels with respect to the development and enforcement of environmental laws, regulations, and policies. Fair treatment implies that no population should be forced to shoulder a disproportionate share of exposure to the negative effects of pollution due to lack of political or economic strength.
Erosion
The wearing away of soil by wind or water, intensified by land-clearing practices related to farming, residential or industrial development, road building, or logging.
Estuary
A complex ecosystem between a river and near-shore ocean waters where fresh and salt water mix. These brackish areas include bays, mouths of rivers, salt marshes, wetlands, and lagoons and are influenced by tides and currents. Estuaries provide valuable habitat for marine animals, birds, and other wildlife.
Exposure
Radiation or pollutants that come into contact with the body and present a potential health threat. The most common routes of exposure are through the skin, mouth, or by inhalation.

F

First Draw
The water that comes out when a faucet in the kitchen or bathroom is first opened, which is likely to have the highest level of lead contamination from old plumbing solder and pipes.
Fugitive Emissions
Air pollutants released to the air other than those from stacks or vents; typically small releases from leaks in plant equipment such as valves, pump seals, flanges, sampling connections, etc.
Fungicide
A pesticide used to control or destroy fungi on food or grain crops.

G

Garbage
Food waste (animal and vegetable) resulting from the handling, storage, packaging, sale, preparation, cooking, and serving of foods.
Greenhouse effect
Process by which significant changes in the chemistry of Earth's atmosphere may enhance the natural process that warms our planet and elevates temperatures. If the effect is intensified and Earth's average temperatures changes, a number of plant and animal species could be threatened with extinction.Greenhouse gas
A gaseous component of the atmosphere contributing to the greenhouse effect. Greenhouse gases are transparent to certain wavelengths of the sun's energy, allowing them to penetrate deep into the atmosphere or all the way into the Earth's surface. Greenhouse gases and clouds prevent some of infrared radiation from escaping, trapping the heat near the Earth's surface where it warms the lower atmosphere. Alteration of this natural barrier of atmospheric gases can raise or lower the mean global temperature of the Earth.
Ground Water
Water found below the surface of the land, usually in porous rock formations. Ground water is the source of water found in wells and springs and is used frequently for drinking.

H

Heavy Metal
A common hazardous waste; can damage organisms at low concentrations and tends to accumulate in the food chain.
Herbicide
A pesticide designed to control or kill plants, weeds, or grasses. Almost 70% of all pesticide used by farmers and ranchers are herbicides. These chemicals have wide-ranging effects on non-target species (other than those the pesticide is meant to control).
Household or Domestic Waste
Solid waste, composed of garbage and rubbish, which normally originates from residential, private households, or apartment buildings. Domestic waste may contain a significant amount of toxic or hazardous waste from improperly discarded pesticides, paints, batteries, and cleaners.
Hydrocarbons
Chemicals that consist entirely of hydrogen and carbon. Hydrocarbons contribute to air pollution problems like smog.
Hydrosphere
The totality of water encompassing the Earth, comprising all the bodies of water, ice and water vapor in the atmosphere.

I

Incineration
The destruction of solid, liquid, or gaseous wastes by controlled burning at high temperatures. Hazardous organic compounds are converted to ash, carbon dioxide, and water. Burning destroys organics, reduces the volume of waste, and vaporizes water and other liquids the wastes may contain. The residue ash produced may contain some hazardous material, such as non-combustible heavy metals, concentrated from the original waste.
Indoor Air
Breathing air inside a habitable structure, often highly polluted because of lack of exchange with fresh oxygen from outdoors. Solvents, smoke, paints, furniture glues, carpet padding, and other synthetic chemicals trapped inside contribute to an often unhealthy environment.
Industrial Waste
Unwanted materials produced in or eliminated from an industrial operation and categorized under a variety of headings, such as liquid wastes, sludge, solid wastes, and hazardous wastes.
Insecticide
A pesticide compound specifically used to kill or prevent the growth of insects.
Irradiated Food
Food that has been briefly exposed to radioactivity (usually gamma rays) to kill insects, bacteria, and mold. Irradiated food can be stored without refrigeration or chemical preservatives and has a long "shelf life."

L

Landfill
A method for final disposal of solid waste on land. The refuse is spread and compacted and a cover of soil applied so that effects on the environment (including public health and safety) are minimized. Under current regulations, landfills are required to have liners and leachate treatment systems to prevent contamination of ground water and surface waters. An industrial landfill disposes of non-hazardous industrial wastes. A municipal landfill disposes of domestic waste including garbage, paper, etc. This waste may include toxins that are used in the home, such as insect sprays and powders, engine oil, paints, solvents, and weed killers.
Litter
The highly visible portion of solid waste (usually packaging material) which is generated by the consumer and carelessly discarded outside of the regular garbage disposal system, as on the highways or in streets.
Microorganisms
Bacteria, yeasts, simple fungi, algae, protozoans, and a number of other organisms that are microscopic in size. Most are beneficial but some produce disease. Others are involved in composting and sewage treatment.
Milligrams/liter (mg/l)
A measure of concentration used in the measurement of fluids. Mg/l is the most common way to present a concentration in water and is roughly equivalent to parts per million. A measure of concentration used in the measurement of fluids. Mg/l is the most common way to present a concentration in water and is roughly equivalent to parts per million.
Mutagenicity
The property of a chemical that causes the genetic characteristics of an organism to change in such a way that future generations are permanently affected.

O

Organically Grown
Food, feed crops, and livestock grown within an intentionally-diversified, self-sustaining agro-ecosystem. In practice, farmers build up nutrients in the soil using compost, agricultural wastes, and cover crops instead of synthetically derived fertilizers to increase productivity, rotate crops, weed mechanically, and reduce dramatically their dependence on the entire family of pesticides. Farmers must be certified to characterize crops as organically grown and can only use approved natural and synthetic biochemicals, agents, and materials for three consecutive years prior to harvest. Livestock must be fed a diet that includes grains and forages that have been organically grown and cannot receive hormones, sub-therapeutic antibiotics, or other growth promoters.
Organism
Any living being, whether plant, mammal, bird, insect, reptile, fish, crustacean, aquatic or estuarine animal, or bacterium.
Oxidant
A substance containing oxygen that reacts chemically with other materials to produce new substances. Oxidants are the primary ingredients in smog.
 Ozone
An almost colorless, gaseous form of oxygen with an odor similar to weak chlorine. A relatively unstable compound of three atoms of oxygen, ozone constitutes -- on the average -- less than one part per million (ppm) ozone concentration in the atmosphere (peak ozone concentration in the stratosphere can get as high as 10 ppm). Yet ozone in the stratosphere absorbs nearly all of the biologically damaging solar ultraviolet radiation before it reaches the Earth's surface where it can cause skin cancer, cataracts, and immune deficiencies and can harm crops and aquatic ecosystems.
 Ozone hole
A large area of intense stratospheric ozone depletion over the Antarctic continent that typically occurs annually between late August and early October, and generally ends in mid-November. This severe ozone thinning has increased conspicuously since the late seventies and early eighties. This phenomenon is the result of chemical mechanisms initiated by man-made chlorofluorocarbons (see CFC's). Continued buildup of CFC's is expected to lead to additional ozone loss worldwide.
Ozone layer
The layer of ozone that begins approximately 15 km above Earth and thins to an almost negligible amount at at about 50 km, shields the Earth from harmful ultraviolet radiation from the sun. The highest natural concentration of ozone (approximately 10 parts per million by volume) occurs in the stratosphere at approximately 25 km above Earth. The stratospheric ozone concentration changes throughout the year as stratospheric circulation changes with the seasons. Natural events such as volcanoes and solar flares can produce changes in ozone concentration, but mad-made changes are of the greatest concern.

P

Pesticide
Substances intended to repel, kill, or control any species designated a "pest" including weeds, insects, rodents, fungi, bacteria, or other organisms. The family of pesticides includes herbicides, insecticides, rodenticides, fungicides, and bactericides.
pH
The measure of acidity or alkalinity of a chemical solution, from 014. Anything neutral, for example, has a pH of 7. Acids have a pH less than 7, bases (alkaline) greater than 7.
Plume
A concentration of contaminants in air, soil, or water usually extending from a distinct source.
Pollution
Any substances in water, soil, or air that degrade the natural quality of the environment, offend the senses of sight, taste, or smell, or cause a health hazard. The usefulness of the natural resource is usually impaired by the presence of pollutants and contaminants.
Pollution Prevention
Actively identifying equipment, processes, and activities which generate excessive wastes or use toxic chemicals and then making substitutions, alterations, or product improvements. Conserving energy and minimizing wastes are pollution prevention concepts used in manufacturing, sustainable agriculture, recycling, and clean air/clean water technologies.

R

Radioactive Waste
Any waste that emits energy as rays, waves, or streams of energetic particles. Radioactive materials are often mixed with hazardous waste, usually from nuclear reactors, research institutions, or hospitals.
Radon
A colorless, naturally occurring gas formed by radioactive decay of radium atoms. Radon accumulating in basements and other areas of buildings without proper ventilation has been identified as a leading cause of lung cancer.
 Rain forest
An evergreen woodland of the tropics distinguished by a continuous leaf canopy and an average rainfall of about 100 inches per year. Rain forests play an important role in the global environment. The Earth sustains life because of critical balances and interactions among many factors. Were there not processes at work that limit the effects of other essential processes, Earth would become uninhabitable. Destruction of tropical rain forests reduces the amount of leaf area in the tropics, and consequently the amount of carbon dioxide absorbed, causing increases in levels of carbon dioxide and other atmospheric gases. It is estimated that cutting and burning of tropical forests contributes about 20 percent of the carbon dioxide added to the atmosphere each year. The World Resources Institute and the International Institute for Environment and Development have reported that the world's tropical forests are being destroyed at the rate of fifty-four acres per minute, or twenty-eight million acres lost annually. Rain forest destruction also means the loss of a wide spectrum of biological life, erosion of soil, and possible desertification. 
Recycling
Reusing materials and objects in original or changed forms rather than discarding them as wastes.
Reference Dose (RfD)
The particular concentration of a chemical that is known to cause health problems. A standard that also may be referred to as the acceptable daily intake.
Release
Any spilling, leaking, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment of a hazardous or toxic chemical, or extremely hazardous substance.
Resource Recovery
The extraction of useful materials or energy from solid waste. Such materials can include paper, glass, and metals that can be reprocessed for re-use. Resource recovery also is employed in pollution prevention.
Rodenticide
A pesticide or other agent used to kill rats and other rodents or to prevent them from damaging food, crops, or forage.

S

Sanitary Water
Water discharged from restrooms, showers, food preparation facilities, or other nonindustrial operations; also known as "gray water."
Septic tank
An underground tank to collect wastes from homes that are not connected to a municipal sewer system. Waste goes from the home to the tank and is decomposed by bacteria. Solids and dead bacteria settle to the bottom as sludge while the liquid portion flows into the ground through drains. While properly placed and maintained septic systems can effectively treat domestic wastewater, others are a major source of ground water and surface water pollution.
Smog
Dust, smoke, or chemical fumes that pollute the air and make hazy, unhealthy conditions (literally, the word is a blend of moke and fog). Automobile, truck, bus, and other vehicle exhausts and particulates are usually trapped close to the ground, obscuring visibility and contributing to a number of respiratory problems.
Solid Waste
Any solid, semi-solid, liquid, or contained gaseous materials discarded from industrial, commercial, mining, or agricultural operations, and from community activities. Solid waste includes garbage, construction debris, commercial refuse, sludge from water supply or waste treatment plants, or air pollution control facilities, and other discarded materials.
Solid Waste Management Facility
Any disposal or resource recovery system; any system, program, or facility for resource conservation; any facility for the treatment of solid wastes.
Source Reduction
The design, manufacture, purchase, or use of materials (such as products and packaging) to reduce the amount or toxicity of garbage generated. Source reduction can help reduce waste disposal and handling charges because the costs of recycling, municipal composting, landfilling, and combustion are avoided. Source reduction conserves resources and reduces pollution.
Source Separation
Organizing materials by type (such as paper, metal, plastic, and glass) so that these items can be recycled instead of thrown away. For example, many of us separate these items from the rest of our household and office wastes. Industries also organize materials in this fashion.
Surface Water
All water naturally open to the atmosphere (rivers, lakes, reservoirs, ponds, streams, seas, estuaries) and all springs, wells, or other collectors directly influenced by surface water.
Sustainable Agriculture
Environmentally friendly methods of farming that allow the production of crops or livestock without damage to the farm as an ecosystem, including effects on soil, water supplies, biodiversity, or other surrounding natural resources. The concept of sustainable agriculture is an "intergenerational" one in which we pass on a conserved or improved natural resource base instead of one which has been depleted or polluted. Terms often associated with farms or ranches that are self-sustaining include "low-input," organic, "ecological," "biodynamic," and "permaculture."
Synergism
The cooperative action of two or more organisms producing a greater total result than the sum of their independent effects; chemicals or muscles in synergy enhance the effectiveness of one another beyond what an individual could have produced.

T

Teratogen
A substance capable of causing birth defects.
Tolerance
Permissible residue level for pesticides in raw agricultural produce and processed foods. Whenever a pesticide is registered for use on a food or feed crop, a tolerance must be established.
Tonnage
The amount of waste that a landfill accepts, usually expressed as tons per month. The rate at which a landfill accepts waste is limited by the landfill's permit.
Toxic Chemical
Substances that can cause severe illness, poisoning, birth defects, disease, or death when ingested, inhaled, or absorbed by living organisms.
Toxic Cloud
An airborne mass of gases, vapors, fumes, or aerosols of toxic materials.

V

Volatile
Any substance which evaporates quickly.

W

Water Quality Standard (WQS)
The combination of a designated use and the maximum concentration of a pollutant which will protect that use for any given body of water. For example, in a trout stream, the concentration of iron should not exceed 1 mg/l.
Wellhead Protection Area
A protected surface and subsurface zone surrounding a well or well field that supplies a public water system and through which contaminants could likely reach well water.
Wetlands
Areas that are soaked or flooded by surface or ground water frequently enough or for sufficient duration to support plants, birds, animals, and aquatic life. Wetlands generally include swamps, marshes, bogs, estuaries, and other inland and coastal areas, and are federally protected. Wetlands frequently serve as recharge/discharge areas and are known as "nature's kidneys" since they help purify water. Wetlands also have been referred to as natural sponges that absorb flood waters, functioning like natural tubs to collect overflow. Wetlands are important wildlife habitats, breeding grounds, and nurseries because of their biodiversity. Many endangered species as well as countless estuarine and marine fish and shellfish, mammals, waterfowl, and other migratory birds use wetland habitat for growth, reproduction, food, and shelter. Wetlands are among the most fertile, natural ecosystems in the world since they produce great volumes of food (plant material).
Wildlife Refuge
An area designated for the protection of wild animals, within which hunting and fishing are either prohibited or strictly controlled.
Wood Treatment Facility
An industrial facility which treats lumber and other wood products for outdoor use. The process involves use of chromated copper arsenate and other toxic chemicals which are regulated as hazardous materials.

X

Xenobiotic
A term for non-natural or man-made substances found in the environment (i.e., synthetics, plastics).

A

Abutment - In coal mining, (1) the solid coal along each side of a narrow roadway and (2) the solid coal ahead of a longwall face or the settled packs behind the face.
Acid deposition or acid rain – Refers loosely to a mixture of wet and dry deposited material from the atmosphere containing higher than normal amounts of nitric and sulfuric acids. Acid rain formation results from both natural sources, such as volcanoes and decaying vegetation, and man-made sources, primarily emissions of sulfur and nitrogen oxides resulting from fossil fuel combustion.
Acid mine water - Mine water that contains free sulfuric acid, mainly due to the weathering of iron pyrites.
Active workings - Ventilated areas of a mine where miners are normally required to work or travel.
Adit - A nearly horizontal passage from the surface by which a mine is entered and dewatered. A blind horizontal opening into a mountain, with only one entrance.
Advance - Mining in the same direction or order of sequence; first mining as distinguished from retreat.
Air split - The division of a current of air into two or more parts.
Airway - Any passage through which air is carried. Also known as an air course.
Anemometer - Instrument for measuring air velocity.
Angle of dip - The angle at which strata or mineral deposits are inclined to the horizontal plane.
Angle of draw - In coal mine subsidence, the angle which bisects the angle between the vertical and the angle of repose of the material. The angle of draw is  20° for flat seams. For dipping seams the angle of break increases, being 35.8° from the vertical for a 40° dip.
Angle of repose - The maximum angle from horizontal at which a given material will rest on a given surface without sliding or rolling.
Anticline - An upward fold or arch of rock strata.
Aquifer - A water-bearing bed of porous rock, often sandstone.
Arching - Fracture processes around a mine opening leading to stabilization by an arching effect.
Area (of an airway) - Average width multiplied by average height of airway, expressed in square feet.
Auger - A rotary drill that uses a screw device to penetrate, break, and then transport the drilled material (coal).
Auger Mining - Removes coal by drilling or cutting horizontally into the coal seam.
Auxiliary operations - All activities supportive of but not contributing directly to mining.
Auxiliary ventilation - A portion of the main ventilating current directed to the face of a dead end entry by means of an auxiliary fan and tubing.
Azimuth - A surveying term that references the angle measured clockwise from any meridian (the established line of reference).

B

Back - The roof or upper part in any underground mining cavity.
Backfill – Mine waste or rock used to support the roof after coal removal.
Barren - Term used to describe rock or vein material containing no minerals of value.  Term used to describe strata containing no coal or containing coal in seams too thin to be workable.
Barricading - Enclosing part of a mine to prevent inflow of noxious gasses from a mine fire or an explosion.
Barrier - Barrier pillars are solid blocks of coal left between two mines or sections of a mine to prevent accidents due to inrushes of water or gas, or from explosions and mine fires.
Beam - A bar or straight girder used to support a span of roof between two support props or walls.
Beam building - The creation of a strong, inflexible beam by bolting or otherwise fastening together several weaker layers.
Bearing – A surveying term used to designate direction. The bearing of a line is the acute horizontal angle between the meridian (an established line of reference) and the line.
Bearing plate - A plate used to distribute a given load.  In roof bolting, the plate used between the bolt head and the roof.
Bed - A stratum of coal or other sedimentary deposit.
Belt conveyor - A looped belt on which coal or other materials can be carried and which is generally constructed of flame-resistant material or of reinforced rubber or rubber-like substance.
Belt idler - A roller, usually of cylindrical shape, which is supported on a frame and which, in turn, supports or guides a conveyor belt. Idlers are not powered but turn by contact with the moving belt.
Belt take-up - A belt pulley, generally under a conveyor belt, kept under strong tension parallel to the belt line. Its purpose is to automatically compensate for any slack in the belting created by start-up, etc.
Bench - One of two or more divisions of a coal seam separated by slate or formed by the process of cutting the coal.
Beneficiation - The treatment of mined material, making it more concentrated or richer.
Berm - A pile or mound of material capable of restraining a vehicle.
Binder - A streak of impurity in a coal seam.
Bit - The hardened and strengthened device at the end of a drill rod that transmits the energy of breakage to the rock. The size of the bit determines the size of the hole. A bit may be either detachable from or integral with its supporting drill rod.
Bituminous coal – A middle rank coal (between subbituminous and anthracite) formed by additional pressure and heat on lignite. Usually has a high Btu value and may be referred to as "soft coal."
Black damp - An atmosphere depleted of oxygen or an atmosphere having an excess of carbon dioxide.
Blasting agent - Any material consisting of a mixture of a fuel and an oxidizer.
Blasting cap - A detonator containing a charge of detonating compound, which is ignited by electric current or the spark of a fuse. Used for detonating explosives.
Blasting circuit - Electric circuits used to fire electric detonators or to ignite an igniter cord by means of an electric starter.
Bleeder or bleeder entries - Special air courses developed and maintained as part of the mine ventilation system and designed to continuously move air-methane mixtures away from the active workings and into mine-return air courses. Alt: Exhaust ventilation lateral.
Bolt torque - The turning force in foot-pounds applied to a roof bolt to achieve an installed tension.
Borehole - Any deep or long drill-hole, usually associated with a diamond drill.
Borrow Area - An area from which soil is taken to be used in the reclamation of a different area.
Bottom - Floor or underlying surface of an underground excavation.
Box-type magazine - A small, portable magazine used to store limited quantities of explosives or detonators for short periods of time at locations in the mine which are convenient to the blasting sites at which they will be used.
Brattice or brattice cloth - Fire-resistant fabric or plastic partition used in a mine passage to confine the air and force it into the working place. Also termed "line brattice," "line canvas," or "line curtain."
Break line - The line that roughly follows the rear edges of coal pillars that are being mined. The line along which the roof of a coal mine is expected to break.
Breakthrough - A passage for ventilation that is cut through the pillars between rooms.
Bridge carrier - A rubber-tire-mounted mobile conveyor, about 10 meters long, used as an intermediate unit to create a system of articulated conveyors between a mining machine and a room or entry conveyor.
Bridge conveyor - A short conveyor hung from the boom of mining or lading machine or haulage system with the other end attached to a receiving bin that dollies along a frame supported by the room or entry conveyor, tailpiece. Thus, as the machine boom moves, the bridge conveyor keeps it in constant connection with the tailpiece.
Brow - A low place in the roof of a mine, giving insufficient headroom.
Brushing - Digging up the bottom or taking down the top to give more headroom in roadways.
BTU – British thermal unit. A measure of the energy required to raise the temperature of one pound of water one degree Fahrenheit.
Bug dust - The fine particles of coal or other material resulting form the boring or cutting of the coal face by drill or machine.
Bump (or burst) - A violent dislocation of the mine workings which is attributed to severe stresses in the rock surrounding the workings.
Butt cleat - A short, poorly defined vertical cleavage plane in a coal seam, usually at right angles to the long face cleat.

C

Cage - In a mine shaft, the device, similar to an elevator car, that is used for hoisting personnel and materials.
Calorific value - The quantity of heat that can be liberated from one pound of coal or oil, measured in BTU's.
Cannel coal - A massive, non-caking block coal with a fine, even grain and a conchoidal fracture which has a high percentage of hydrogen, burns with a long, yellow flame, and is extremely easy to ignite.
Canopy - A protective covering of a cab on a mining machine.
Cap - A miner's safety helmet. Also, a highly sensitive, encapsulated explosive that is used to detonate larger but less sensitive explosives.
Cap block - A flat piece of wood inserted between the top of the prop and the roof to provide bearing support.
Car - A railway wagon, especially any of the wagons adapted to carrying coal, ore, and waste underground.
Car-dump - The mechanism for unloading a loaded car.
Carbide bit - More correctly, cemented tungsten carbide. A cutting or drilling bit for rock or coal, made by fusing an insert of molded tungsten carbide to the cutting edge of a steel bit shank.
Cast - A directed throw; in strip-mining, the overburden is cast from the coal to the previously mined area.
Certified - Describes a person who has passed an examination to do a required job.
Chain conveyor - A conveyor on which the material is moved along solid pans (troughs) by the action of scraper crossbars attached to powered chains.
Chain pillar - The pillar of coal left to protect the gangway or entry and the parallel airways.
Check curtain - Sheet of brattice cloth hung across an airway to control the passage of the air current.
Chock - Large hydraulic jacks used to support roof in longwall and shortwall mining systems.
Clay vein - A body of clay-like material that fills a void in a coal bed.
Cleat - The vertical cleavage of coal seams. The main set of joints along which coal breaks when mined.
Clean Air Act Amendments of 1990 – A comprehensive set of amendments to the federal law governing the nation's air quality. The Clean Air Act was originally passed in 1970 to address significant air pollution problems in our cities. The 1990 amendments broadened and strengthened the original law to address specific problems such as acid deposition, urban smog, hazardous air pollutants and stratospheric ozone depletion.
Clean Coal Technologies – A number of innovative, new technologies designed to use coal in a more efficient and cost-effective manner while enhancing environmental protection. Several promising technologies include: fluidized-bed combustion, integrated gasification combined cycle, limestone injection multi-stage burner, enhanced flue gas desulfurization (or "scrubbing"), coal liquefaction and coal gasification.
Coal - A solid, brittle, more or less distinctly stratified combustible carbonaceous rock, formed by partial to complete decomposition of vegetation; varies in color from dark brown to black; not fusible without decomposition and very insoluble.
Coal dust - Particles of coal that can pass a No. 20 sieve.
Coal Gasification – The conversion of coal into a gaseous fuel.
Coal mine - An area of land and all structures, facilities, machinery, tools, equipment, shafts, slopes, tunnels, excavations, and other property, real or personal, placed upon, under, or above the surface of such land by any person, used in extracting coal from its natural deposits in the earth by any means or method, and the work of preparing the coal so extracted, including coal preparation facilities. British term is "colliery".
Coal reserves - Measured tonnages of coal that have been calculated to occur in a coal seam within a particular property.
Coal washing – The process of separating undesirable materials from coal based on differences in densities. Pyritic sulfur, or sulfur combined with iron, is heavier and sinks in water; coal is lighter and floats.
Coke – A hard, dry carbon substance produced by heating coal to a very high temperature in the absence of air.
Collar - The term applied to the timbering or concrete around the mouth or top of a shaft. The beginning point of a shaft or drill hole at the surface.
Colliery - British name for coal mine.
Column flotation – A precombustion coal cleaning technology in which coal particles attach to air bubbles rising in a vertical column. The coal is then removed at the top of the column.
Comminution - The breaking, crushing, or grinding of coal, ore, or rock.
Competent rock - Rock which, because of its physical and geological characteristics, is capable of sustaining openings without any structural support except pillars and walls left during mining (stalls, light props, and roof bolts are not considered structural support).
Contact - The place or surface where two different kinds of rocks meet. Applies to sedimentary rocks, as the contact between a limestone and a sandstone, for example, and to metamorphic rocks; and it is especially applicable between igneous intrusions and their walls.
Continuous miner - A machine that constantly extracts coal while it loads it. This is to be distinguished from a conventional, or cyclic, unit which must stop the extraction process in order for loading to commence.
Contour - An imaginary line that connects all points on a surface having the same elevation.
Conventional mining – The first fully-mechanized underground mining method involving the insertion of explosives in a coal seam, the blasting of the seam, and the removal of the coal onto a conveyor or shuttle car by a loading machine.
Conveyor - An apparatus for moving material from one point to another in a continuous fashion. This is accomplished with an endless (that is, looped) procession of hooks, buckets, wide rubber belt, etc.
Core sample – A cylinder sample generally 1-5" in diameter drilled out of an area to determine the geologic and chemical analysis of the overburden and coal.
Cover - The overburden of any deposit.
Creep - The forcing of pillars into soft bottom by the weight of a strong roof. In surface mining, a very slow movement of slopes downhill.
Crib - A roof support of prop timbers or ties, laid in alternate cross-layers, log-cabin style. It may or may not be filled with debris. Also may be called a chock or cog.
Cribbing - The construction of cribs or timbers laid at right angles to each other, sometimes filled with earth, as a roof support or as a support for machinery.
Crop coal - Coal at the outcrop of the seam. It is usually considered of inferior quality due to partial oxidation, although this is not always the case.
Crossbar - The horizontal member of a roof timber set supported by props located either on roadways or at the face.
Crosscut - A passageway driven between the entry and its parallel air course or air courses for ventilation purposes. Also, a tunnel driven from one seam to another through or across the intervening measures; sometimes called "crosscut tunnel", or "breakthrough". In vein mining, an entry perpendicular to the vein.
Cross entry - An entry running at an angle with the main entry.
Crusher - A machine for crushing rock or other materials. Among the various types of crushers are the ball mill, gyratory crusher, Handsel mill, hammer mill, jaw crusher, rod mill, rolls, stamp mill, and tube mill.
Cutter; Cutting machine - A machine, usually used in coal, that will cut a 10- to 15-cm slot. The slot allows room for expansion of the broken coal. Also applies to the man who operates the machine and to workers engaged in the cutting of coal by prick or drill.
Cycle mining - A system of mining in more than one working place at a time, that is, a miner takes a lift from the face and moves to another face while permanent roof support is established in the previous working face.

D

Demonstrated reserves – A collective term for the sum of coal in both measured and indicated resources and reserves.
Deposit - Mineral deposit or ore deposit is used to designate a natural occurrence of a useful mineral, or an ore, in sufficient extent and degree of concentration to invite exploitation.
Depth - The word alone generally denotes vertical depth below the surface. In the case of incline shafts and boreholes it may mean the distance reached from the beginning of the shaft or hole, the borehole depth, or the inclined depth.
Detectors - Specialized chemical or electronic instruments used to detect mine gases.
Detonator - A device containing a small detonating charge that is used for detonating an explosive, including, but not limited to, blasting caps, exploders, electric detonators, and delay electric blasting caps.
Development mining - Work undertaken to open up coal reserves as distinguished from the work of actual coal extraction.
Diffusion - Blending of a gas and air, resulting in a homogeneous mixture. Blending of two or more gases.
Diffuser fan - A fan mounted on a continuous miner to assist and direct air delivery from the machine to the face.
Dilute - To lower the concentration of a mixture; in this case the concentration of any hazardous gas in mine air by addition of fresh intake air.
Dilution - The contamination of ore with barren wall rock in stopping.
Dip - The inclination of a geologic structure (bed, vein, fault, etc.) from the horizontal; dip is always measured downwards at right angles to the strike.
Dragline – A large excavation machine used in surface mining to remove overburden (layers of rock and soil) covering a coal seam. The dragline casts a wire rope-hung bucket a considerable distance, collects the dug material by pulling the bucket toward itself on the ground with a second wire rope (or chain), elevates the bucket, and dumps the material on a spoil bank, in a hopper, or on a pile.
Drainage - The process of removing surplus ground or surface water either by artificial means or by gravity flow.
Draw slate - A soft slate, shale, or rock from approximately 1 cm to 10 cm thick and located immediately above certain coal seams, which falls quite easily when the coal support is withdrawn.
Drift - A horizontal passage underground. A drift follows the vein, as distinguished from a crosscut that intersects it, or a level or gallery, which may do either.
Drift mine – An underground coal mine in which the entry or access is above water level and generally on the slope of a hill, driven horizontally into a coal seam.
Drill - A machine utilizing rotation, percussion (hammering), or a combination of both to make holes. If the hole is much over 0.4m in diameter, the machine is called a borer.
Drilling - The use of such a machine to create holes for exploration or for loading with explosives.
Dummy - A bag filled with sand, clay, etc., used for stemming a charged hole.
Dump - To unload; specifically, a load of coal or waste; the mechanism for unloading, e.g. a car dump (sometimes called tipple); or, the pile created by such unloading, e.g. a waste dump (also called heap, pile, tip, spoil pike, etc.).

E

Electrical grounding - To connect with the ground to make the earth part of the circuit.
Entry - An underground horizontal or near-horizontal passage used for haulage, ventilation, or as a mainway; a coal heading; a working place where the coal is extracted from the seam in the initial mining; same as "gate" and "roadway," both British terms.
Evaluation - The work involved in gaining a knowledge of the size, shape, position and value of coal.
Exploration - The search for mineral deposits and the work done to prove or establish the extent of a mineral deposit. Alt: Prospecting and subsequent evaluation.
Explosive - Any rapidly combustive or expanding substance. The energy released during this rapid combustion or expansion can be used to break rock.
Extraction - The process of mining and removal of cal or ore from a mine.

F

Face – The exposed area of a coal bed from which coal is being extracted.
Face cleat - The principal cleavage plane or joint at right angles to the stratification of the coal seam.
Face conveyor - Any conveyor used parallel to a working face which delivers coal into another conveyor or into a car.
Factor of safety - The ratio of the ultimate breaking strength of the material to the force exerted against it. If a rope will break under a load of 6000 lbs., and it is carrying a load of 2000 lbs., its factor of safety is 6000 divided by 2000 which equals 3.
Fall - A mass of roof rock or coal which has fallen in any part of a mine.
Fan, auxiliary - A small, portable fan used to supplement the ventilation of an individual working place.
Fan, booster - A large fan installed in the main air current, and thus in tandem with the main fan.
Fan signal - Automation device designed to give alarm if the main fan slows down or stops.
Fault - A slip-surface between two portions of the earth's surface that have moved relative to each other. A fault is a failure surface and is evidence of severe earth stresses.
Fault zone - A fault, instead of being a single clean fracture, may be a zone hundreds or thousands of feet wide. The fault zone consists of numerous interlacing small faults or a confused zone of gouge, breccia, or mylonite.
Feeder - A machine that feeds coal onto a conveyor belt evenly.
Fill - Any material that is put back in place of the extracted ore to provide ground support.
Fire damp - The combustible gas, methane, CH4. Also, the explosive methane-air mixtures with between 5% and 15% methane. A combustible gas formed in mines by decomposition of coal or other carbonaceous matter, and that consists chiefly of methane.
Fissure - An extensive crack, break, or fracture in the rocks.
Fixed carbon – The part of the carbon that remains behind when coal is heated in a closed vessel until all of the volatile matter is driven off.
Flat-lying - Said of deposits and coal seams with a dip up to 5 degrees.
Flight - The metal strap or crossbar attached to the drag chain-and-flight conveyor.
Float dust - Fine coal-dust particles carried in suspension by air currents and eventually deposited in return entries. Dust consisting of particles of coal that can pass through a No. 200 sieve.
Floor - That part of any underground working upon which a person walks or upon which haulage equipment travels; simply the bottom or underlying surface of an underground excavation.
Flue Gas Desulfurization – Any of several forms of chemical/physical processes that remove sulfur compounds formed during coal combustion. The devices, commonly called "scrubbers," combine the sulfur in gaseous emissions with another chemical medium to form inert "sludge" which must then be removed for disposal.
Fluidized Bed Combustion – A process with a high degree of ability to remove sulfur from coal during combustion. Crushed coal and limestone are suspended in the bottom of a boiler by an upward stream of hot air. The coal is burned in this bubbling, liquid-like (or "fluidized") mixture. Rather than released as emissions, sulfur from combustion gases combines with the limestone to form a solid compound recovered with the ash.
Fly ash – The finely divided particles of ash suspended in gases resulting from the combustion of fuel. Electrostatic precipitators are used to remove fly ash from the gases prior to the release from a power plant's smokestack.
Formation – Any assemblage of rocks which have some character in common, whether of origin, age, or composition. Often, the word is loosely used to indicate anything that has been formed or brought into its present shape.
Fossil fuel – Any naturally occurring fuel of an organic nature, such as coal, crude oil and natural gas.
Fracture - A general term to include any kind of discontinuity in a body of rock if produced by mechanical failure, whether by shear stress or tensile stress. Fractures include faults, shears, joints, and planes of fracture cleavage.
Friable - Easy to break, or crumbling naturally. Descriptive of certain rocks and minerals.
Fuse - A cord-like substance used in the ignition of explosives. Black powder is entrained in the cord and, when lit, burns along the cord at a set rate. A fuse can be safely used to ignite a cap, which is the primer for an explosive.

G

Gallery - A horizontal or a nearly horizontal underground passage, either natural or artificial.
Gasification – Any of various processes by which coal is turned into low, medium, or high Btu gases.
Gathering conveyor; gathering belt - Any conveyor which is used to gather coal from other conveyors and deliver it either into mine cars or onto another conveyor. The term is frequently used with belt conveyors placed in entries where a number of room conveyors deliver coal onto the belt.
Geologist - One who studies the constitution, structure, and history of the earth's crust, conducting research into the formation and dissolution of rock layers, analyzing fossil and mineral content of layers, and endeavoring to fix historical sequence of development by relating characteristics to known geological influences (historical geology).
Gob - The term applied to that part of the mine from which the coal has been removed and the space more or less filled up with waste. Also, the loose waste in a mine. Also called goaf.
Global climate change – This term usually refers to the gradual warming of the earth caused by the greenhouse effect. Many scientists believe this is the result of man-made emissions of greenhouse gases such as carbon dioxide, chlorofluorocarbons (CFC) and methane, although there is no agreement among the scientific community on this controversial issue.
Grain - In petrology, that factor of the texture of a rock composed of distinct particles or crystals which depends upon their absolute size.
Grizzly - Course screening or scalping device that prevents oversized bulk material form entering a material transfer system; constructed of rails, bars, beams, etc.
Ground control - The regulation and final arresting of the closure of the walls of a mined area. The term generally refers to measures taken to prevent roof falls or coal bursts.
Ground pressure - The pressure to which a rock formation is subjected by the weight of the superimposed rock and rock material or by diastrophic forces created by movements in the rocks forming the earth's crust. Such pressures may be great enough to cause rocks having a low compressional strength to deform and be squeezed into and close a borehole or other underground opening not adequately strengthened by an artificial support, such as casing or timber.
Gunite - A cement applied by spraying to the roof and sides of a mine passage.

H

Haulage - The horizontal transport of ore, coal, supplies, and waste. The vertical transport of the same is called hoisting.
Haulageway - Any underground entry or passageway that is designed for transport of mined material, personnel, or equipment, usually by the installation of track or belt conveyor.
Headframe - The structure surmounting the shaft which supports the hoist rope pulley, and often the hoist itself.
Heading - A vein above a drift. An interior level or airway driven in a mine. In longwall workings, a narrow passage driven upward from a gangway in starting a working in order to give a loose end.
Head section - A term used in both belt and chain conveyor work to designate that portion of the conveyor used for discharging material.
Heaving - Applied to the rising of the bottom after removal of the coal; a sharp rise in the floor is called a "hogsback".
Highwall – The unexcavated face of exposed overburden and coal in a surface mine or in a face or bank on the uphill side of a contour mine excavation.
Highwall Miner – A highwall mining system consists of a remotely controlled continuous miner which extracts coal and conveys it via augers, belt or chain conveyors to the outside. The cut is typically a rectangular, horizontal cut from a highwall bench, reaching depths of several hundred feet or deeper.
Hogsback - A sharp rise in the floor of a seam.
Hoist - A drum on which hoisting rope is wound in the engine house, as the cage or skip is raised in the hoisting shaft.
Hoisting - The vertical transport coal or material.
Horizon - In geology, any given definite position or interval in the stratigraphic column or the scheme of stratigraphic classification; generally used in a relative sense.
Horseback - A mass of material with a slippery surface in the roof; shaped like a horse's back.
Hydraulic - Of or pertaining to fluids in motion. Hydraulic cement has a composition which permits it to set quickly under water. Hydraulic jacks lift through the force transmitted to the movable part of the jack by a liquid. Hydraulic control refers to the mechanical control of various parts of machines, such as coal cutters, loaders, etc., through the operation or action of hydraulic cylinders.
Hydrocarbon – A family of chemical compounds containing carbon and hydrogen atoms in various combinations, found especially in fossil fuels.

I

Inby - In the direction of the working face.
Incline - Any entry to a mine that is not vertical (shaft) or horizontal (adit). Often incline is reserved for those entries that are too steep for a belt conveyor (+17 degrees -18 degrees), in which case a hoist and guide rails are employed. A belt conveyor incline is termed a slope. Alt: Secondary inclined opening, driven upward to connect levels, sometimes on the dip of a deposit; also called "inclined shaft".
Incompetent - Applied to strata, a formation, a rock, or a rock structure not combining sufficient firmness and flexibility to transmit a thrust and to lift a load by bending.
Indicated coal resources – Coal for which estimates of the rank, quality, and quantity have been computed partly from sample analyses and measurements and partly from reasonable geologic projections. The points of observation are ½ to 1 ½ miles apart. Indicated coal is projected to extend as an ½ mile wide belt that lies more than ¼ mile from the outcrop or points of observation or measurement.
Inferred coal resources – Coal in unexplored extensions of the demonstrated resources for which estimates of the quality and size are based on geologic evidence and projection. Quantitative estimates are based largely on broad knowledge of the geologic character of the deposit and for which there are few, if any, samples or measurements. The estimates are based on an assumed continuity or repletion of which there is geologic evidence; this evidence may include comparison with deposits of similar type. Bodies that are completely concealed may be included if there is specific geologic evidence of their presence. The points of observation are 1 ½ to 6 miles apart.
In situ - In the natural or original position. Applied to a rock, soil, or fossil when occurring in the situation in which it was originally formed or deposited.
Intake - The passage through which fresh air is drawn or forced into a mine or to a section of a mine.
Intermediate section - A term used in belt and chain conveyor network to designate a section of the conveyor frame occupying a position between the head and foot sections.
Immediate roof - The roof strata immediately above the coalbed, requiring support during the excavation of coal.
Isopach - A line, on a map, drawn through points of equal thickness of a designated unit. Synonym for isopachous line; isopachyte.

J

Jackleg - A percussion drill used for drifting or stopping that is mounted on a telescopic leg which has an extension of about 2.5 m. The leg and machine are hinged so that the drill need not be in the same direction as the leg.
Jackrock – A caltrop or other object manufactured with one or more rounded or sharpened points, which when placed or thrown present at least one point at such an angle that it is peculiar to and designed for use in puncturing or damaging vehicle tires. Jackrocks are commonly used during labor disputes.
Job Safety Analysis (J.S.A.) - A job breakdown that gives a safe, efficient job procedure.
Joint - A divisional plane or surface that divides a rock and along which there has been no visible movement parallel to the plane or surface.

K

Kettle bottom - A smooth, rounded piece of rock, cylindrical in shape, which may drop out of the roof of a mine without warning. The origin of this feature is thought to be the remains of the stump of a tree that has been replaced by sediments so that the original form has been rather well preserved.
Kerf - The undercut of a coal face.

L

Lamp - The electric cap lamp worn for visibility. Also, the flame safety lamp used in coal mines to detect methane gas concentrations and oxygen deficiency.
Layout - The design or pattern of the main roadways and workings. The proper layout of mine workings is the responsibility of the manager aided by the planning department.
Lift - The amount of coal obtained from a continuous miner in one mining cycle.
Liquefaction – The process of converting coal into a synthetic fuel, similar in nature to crude oil and/or refined products, such as gasoline.
Lithology - The character of a rock described in terms of its structure, color, mineral composition, grain size, and arrangement of its component parts; all those visible features that in the aggregate impart individuality of the rock. Lithology is the basis of correlation in coal mines and commonly is reliable over a distance of a few miles.
Load - To place explosives in a drill hole. Also, to transfer broken material into a haulage device.
Loading machine - Any device for transferring excavated coal into the haulage equipment.
Loading pocket - Transfer point at a shaft where bulk material is loaded by bin, hopper, and chute into a skip.
Longwall Mining – One of three major underground coal mining methods currently in use. Employs a steal plow, or rotation drum, which is pulled mechanically back and forth across a face of coal that is usually several hundred feet long. The loosened coal falls onto a conveyor for removal from the mine.
Loose coal - Coal fragments larger in size than coal dust.
Low voltage - Up to and including 660 volts by federal standards.

M

Main entry - A main haulage road. Where the coal has cleats, main entries are driven at right angles to the face cleats.
Main fan - A mechanical ventilator installed at the surface; operates by either exhausting or blowing to induce airflow through the mine roadways and workings.
Manhole - A safety hole constructed in the side of a gangway, tunnel, or slope in which miner can be safe from passing locomotives and car. Also called a refuge hole.
Man trip - A carrier of mine personnel, by rail or rubber tire, to and from the work area.
Manway - An entry used exclusively for personnel to travel form the shaft bottom or drift mouth to the working section; it is always on the intake air side in gassy mines. Also, a small passage at one side or both sides of a breast, used as a traveling way for the miner, and sometimes, as an airway, or chute, or both.
Measured coal resources – Coal for which estimates of the rank, quality, and quantity have been computed from sample analyses and measurements from closely spaced and geologically well-known sample sites, such as outcrops, trenches, mine workings, and drill holes. The points of observation and measurement are so closely spaced and the thickness and extent of coals are so well defined that the tonnage is judged to be accurate within 20 percent of true tonnage. Although the spacing of the points of observation necessary to demonstrate continuity of the coal differs from region to region according to the character of the coal beds, the points of observation are no greater than ½ mile apart. Measured coal is projected to extend as a ¼-mile wide belt from the outcrop or points of observation or measurement.
Meridian -– A surveying term that establishes a line of reference. The bearing is used to designate direction. The bearing of a line is the acute horizontal angle between the meridian and the line. Azimuths are angles measured clockwise from any meridian.
Methane – A potentially explosive gas formed naturally from the decay of vegetative matter, similar to that which formed coal. Methane, which is the principal component of natural gas, is frequently encountered in underground coal mining operations and is kept within safe limits through the use of extensive mine ventilation systems.
Methane monitor - An electronic instrument often mounted on a piece of mining equipment, that detects and measures the methane content of mine air.
Mine development - The term employed to designate the operations involved in preparing a mine for ore extraction. These operations include tunneling, sinking, cross-cutting, drifting, and raising.
Mine mouth electric plant – A coal burning electric-generating plant built near a coal mine.
Miner - One who is engaged in the business or occupation of extracting ore, coal, precious substances, or other natural materials from the earth's crust.
Mineral - An inorganic compound occurring naturally in the earth's crust, with a distinctive set of physical properties, and a definite chemical composition.
Mining Engineer - A person qualified by education, training, and experience in mining engineering. A trained engineer with knowledge of the science, economics, and arts of mineral location, extraction, concentration and sale, and the administrative and financial problems of practical importance in connection with the profitable conduct of mining.
Misfire - The complete or partial failure of a blasting charge to explode as planned.
MSHA - Mine Safety and Health Administration; the federal agency which regulates coal mine health and safety.
Mud cap - A charge of high explosive fired in contact with the surface of a rock after being covered with a quantity of wet mud, wet earth, or sand, without any borehole being used. Also termed adobe, dobie, and sandblast (illegal in coal mining).

N

Natural ventilation - Ventilation of a mine without the aid of fans or furnaces.
Nip - Device at the end of the trailing cable of a mining machine used for connecting the trailing cable to the trolley wire and ground.

O

Open end pillaring - A method of mining pillars in which no stump is left; the pockets driven are open on the gob side and the roof is supported by timber.
Open pit box cut - A method of mining in which the overburden and underlying mineral are removed from the earth in large, rectangular sections.   The sections are removed in a sequence so that overburden being removed from a section being excavated is used to backfill the previous section.
Outby; outbye - Nearer to the shaft, and hence farther from the working face. Toward the mine entrance. The opposite of inby.
Outcrop – Coal that appears at or near the surface.
Overburden – Layers of soil and rock covering a coal seam. Overburden is removed prior to surface mining and replaced after the coal is taken from the seam.
Overcast (undercast) - Enclosed airway which permits one air current to pass over (under) another without interruption.

P

Panel - A coal mining block that generally comprises one operating unit.
Panic bar - A switch, in the shape of a bar, used to cut off power at the machine in case of an emergency.
Parting - (1) A small joint in coal or rock; (2) a layer of rock in a coal seam; (3) a side track or turnout in a haulage road.
Peat – The partially decayed plant matter found in swamps and bogs, one of the earliest stages of coal formation.
Percentage extraction - The proportion of a coal seam which is removed from the mine. The remainder may represent coal in pillars or coal which is too thin or inferior to mine or lost in mining. Shallow coal mines working under townships, reservoirs, etc., may extract 50%, or less, of the entire seam, the remainder being left as pillars to protect the surface. Under favorable conditions, longwall mining may extract from 80 to 95% of the entire seam. With pillar methods of working, the extraction ranges from 50 to 90% depending on local conditions.
Percussion drill - A drill, usually air powered, that delivers its energy through a pounding or hammering action.
Permissible - That which is allowable or permitted. It is most widely applied to mine equipment and explosives of all kinds which are similar in all respects to samples that have passed certain tests of the MSHA and can be used with safety in accordance with specified conditions where hazards from explosive gas or coal dust exist.
Permit – As it pertains to mining, a document issued by a regulatory agency that gives approval for mining operations to take place.
Piggy-back - A bridge conveyor.
Pillar - An area of coal left to support the overlying strata in a mine; sometimes left permanently to support surface structures.
Pillar robbing - The systematic removal of the coal pillars between rooms or chambers to regulate the subsidence of the roof. Also termed "bridging back" the pillar, "drawing" the pillar, or "pulling" the pillar.
Pinch - A compression of the walls of a vein or the roof and floor of a coal seam so as to "squeeze" out the coal.
Pinch – A compression of the roof and floor of a coal seam so as to "squeeze" out the coal.
Pinning - Roof bolting.
Pitch - The inclination of a seam; the rise of a seam.
Plan - A map showing features such as mine workings or geological structures on a horizontal plane.
Pneumoconiosis - A chronic disease of the lung arising from breathing coal dust.
Portal - The structure surrounding the immediate entrance to a mine; the mouth of an adit or tunnel.
Portal bus - Track-mounted, self-propelled personnel carrier that holds 8 to 12 people.
Post - The vertical member of a timber set.
Preparation plant - A place where coal is cleaned, sized, and prepared for market.
Primary roof - The main roof above the immediate top. Its thickness may vary from a few to several thousand feet.
Primer (booster) - A package or cartridge of explosive which is designed specifically to transmit detonation to other explosives and which does not contain a detonator.
Prop - Coal mining term for any single post used as roof support. Props may be timber or steel; if steel--screwed, yieldable, or hydraulic.
Proximate analysis - A physical, or non-chemical, test of the constitution of coal. Not precise, but very useful for determining the commercial value. Using the same sample (1 gram) under controlled heating at fixed temperatures and time periods, moisture, volatile matter, fixed carbon and ash content are successfully determined. Sulfur and Btu content are also generally reported with a proximate analysis.
Pyrite - A hard, heavy, shiny, yellow mineral, FeS2 or iron disulfide, generally in cubic crystals. Also called iron pyrites, fool's gold, sulfur balls. Iron pyrite is the most common sulfide found in coal mines.

Q

R

Raise - A secondary or tertiary inclined opening, vertical or near-vertical opening driven upward form a level to connect with the level above, or to explore the ground for a limited distance above one level.
Ramp - A secondary or tertiary inclined opening, driven to connect levels, usually driven in a downward direction, and used for haulage.
Ranks of coal – The classification of coal by degree of hardness, moisture and heat content. "Anthracite" is hard coal, almost pure carbon, used mainly for heating homes. "Bituminous" is soft coal. It is the most common coal found in the United States and is used to generate electricity and to make coke for the steel industry. "Subbituminous" is a coal with a heating value between bituminous and lignite. It has low fixed carbon and high percentages of volatile matter and moisture. "Lignite" is the softest coal and has the highest moisture content. It is used for generating electricity and for conversion into synthetic gas. In terms of Btu or "heating" content, anthracite has the highest value, followed by bituminous, subbituminous and lignite.
Reclamation – The restoration of land and environmental values to a surface mine site after the coal is extracted. Reclamation operations are usually underway as soon as the coal has been removed from a mine site. The process includes restoring the land to its approximate original appearance by restoring topsoil and planting native grasses and ground covers.
Recovery - The proportion or percentage of coal or ore mined from the original seam or deposit.
Red dog - A nonvolatile combustion product of the oxidation of coal or coal refuse. Most commonly applied to material resulting from in situ, uncontrolled burning of coal or coal refuse piles. It is similar to coal ash.
Regulator - Device (wall, door) used to control the volume of air in an air split.
Reserve – That portion of the identified coal resource that can be economically mined at the time of determination. The reserve is derived by applying a recovery factor to that component of the identified coal resource designated as the reserve base.
Resin bolting - A method of permanent roof support in which steel rods are grouted with resin.
Resources – Concentrations of coal in such forms that economic extraction is currently or may become feasible. Coal resources broken down by identified and undiscovered resources. Identified coal resources are classified as demonstrated and inferred. Demonstrated resources are further broken down as measured and indicated. Undiscovered resources are broken down as hypothetical and speculative.
Respirable dust - Dust particles 5 microns or less in size.
Respirable dust sample - A sample collected with an approved coal mine dust sampler unit attached to a miner, or so positioned as to measure the concentration of respirable dust to which the miner is exposed, and operated continuously over an entire work shift of such miner.
Retreat mining - A system of robbing pillars in which the robbing line, or line through the faces of the pillars being extracted, retreats from the boundary toward the shaft or mine mouth.
Return - The air or ventilation that has passed through all the working faces of a split.
Return idler - The idler or roller underneath the cover or cover plates on which the conveyor belt rides after the load which it was carrying has been dumped at the head section and starts the return trip toward the foot section.
Rib - The side of a pillar or the wall of an entry. The solid coal on the side of any underground passage. Same as rib pillar.
Rider - A thin seam of coal overlying a thicker one.
Ripper - A coal extraction machine that works by tearing the coal from the face.
Rob - To extract pillars of coal previously left for support.
Robbed out area - Describes that part of a mine from which the pillars have been removed.
Roll - (1) A high place in the bottom or a low place in the top of a mine passage, (2) a local thickening of roof or floor strata, causing thinning of a coal seam.
Roll protection - A framework, safety canopy, or similar protection for the operator when equipment overturns.
Roof - The stratum of rock or other material above a coal seam; the overhead surface of a coal working place. Same as "back" or "top."
Roof bolt - A long steel bolt driven into the roof of underground excavations to support the roof, preventing and limiting the extent of roof falls. The unit consists of the bolt (up to 4 feet long), steel plate, expansion shell, and pal nut. The use of roof bolts eliminates the need for timbering by fastening together, or "laminating," several weaker layers of roof strata to build a "beam."
Roof fall - A coal mine cave-in especially in permanent areas such as entries.
Roof jack - A screw- or pump-type hydraulic extension post made of steel and used as temporary roof support.
Roof sag - The sinking, bending, or curving of the roof, especially in the middle, from weight or pressure.
Roof stress - Unbalanced internal forces in the roof or sides, created when coal is extracted.
Roof support – Posts, jacks, roof bolts and beams used to support the rock overlying a coal seam in an underground mine. A good roof support plan is part of mine safety and coal extraction.
Roof trusses - A combination of steel rods anchored into the roof to create zones of compression and tension forces and provide better support for weak roof and roof over wide areas.
Room and pillar mining – A method of underground mining in which approximately half of the coal is left in place to support the roof of the active mining area. Large "pillars" are left while "rooms" of coal are extracted.
Room neck - The short passage from the entry into a room.
Round - Planned pattern of drill holes fired in sequence in tunneling, shaft sinking, or stopping. First the cut holes are fired, followed by relief, lifter, and rib holes.
Royalty - The payment of a certain stipulated sum on the mineral produced.
Rubbing surface - The total area (top, bottom, and sides) of an airway.
Run-of-mine - Raw material as it exists in the mine; average grade or quality.

S

Safety fuse - A train of powder enclosed in cotton, jute yarn, or waterproofing compounds, which burns at a uniform rate; used for firing a cap containing the detonation compound which in turn sets off the explosive charge.
Safety lamp - A lamp with steel wire gauze covering every opening from the inside to the outside so as to prevent the passage of flame should explosive gas be encountered.
Sampling - Cutting a representative part of an ore (or coal) deposit, which should truly represent its average value.
Sandstone - A sedimentary rock consisting of quartz sand united by some cementing material, such as iron oxide or calcium carbonate.
Scaling - Removal of loose rock from the roof or walls. This work is dangerous and a long bar (called a scaling bar)is often used.
Scoop - A rubber tired-, battery- or diesel-powered piece of equipment designed for cleaning runways and hauling supplies.
Scrubber – Any of several forms of chemical/physical devices that remove sulfur compounds formed during coal combustion. These devices, technically know as flue gas desulfurization systems, combine the sulfur in gaseous emissions with another chemical medium to form inert "sludge," which must then be removed for disposal.
Seam - A stratum or bed of coal.
Secondary roof - The roof strata immediately above the coalbed, requiring support during the excavating of coal.
Section - A portion of the working area of a mine.
Selective mining - The object of selective mining is to obtain a relatively high-grade mine product; this usually entails the use of a much more expensive stopping system and high exploration and development costs in searching for and developing the separate bunches, stringers, lenses, and bands of ore.
Self-contained breathing apparatus - A self-contained supply of oxygen used during rescue work from coal mine fires and explosions; same as SCSR (self-contained self rescuer).
Self-rescuer – A small filtering device carried by a coal miner underground, either on his belt or in his pocket, to provide him with immediate protection against carbon monoxide and smoke in case of a mine fire or explosion. It is a small canister with a mouthpiece directly attached to it. The wearer breathes through the mouth, the nose being closed by a clip. The canister contains a layer of fused calcium chloride that absorbs water vapor from the mine air. The device is used for escape purposes only because it does not sustain life in atmospheres containing deficient oxygen. The length of time a self-rescuer can be used is governed mainly by the humidity in the mine air, usually between 30 minutes and one hour.
Severance – The separation of a mineral interest from other interests in the land by grant or reservation. A mineral dead or grant of the land reserving a mineral interest, by the landowner before leasing, accomplishes a severance as does his execution of a mineral lease.
Shaft - A primary vertical or non-vertical opening through mine strata used for ventilation or drainage and/or for hoisting of personnel or materials; connects the surface with underground workings.
Shaft mine – An underground mine in which the main entry or access is by means of a vertical shaft.
Shale - A rock formed by consolidation of clay, mud, or silt, having a laminated structure and composed of minerals essentially unaltered since deposition.
Shearer - A mining machine for longwall faces that uses a rotating action to "shear" the material from the face as it progresses along the face.
Shift - The number of hours or the part of any day worked.
Shortwall – An underground mining method in which small areas are worked (15 to 150 feet) by a continuous miner in conjunction with the use of hydraulic roof supports.
Shuttle car – A self-discharging truck, generally with rubber tires or caterpillar-type treads, used for receiving coal from the loading or mining machine and transferring it to an underground loading point, mine railway or belt conveyor system.
Sinking - The process by which a shaft is driven.
Skid - A track-mounted vehicle used to hold trips or cars from running out of control. Also it is a flat-bottom personnel or equipment carrier used in low coal.
Skip - A car being hoisted from a slope or shaft.
Slack - Small coal; the finest-sized soft coal, usually less than one inch in diameter.
Slag - The waste product of the process of smelting.
Slate - A miner's term for any shale or slate accompanying coal. Geologically, it is a dense, fine-textured, metamorphic rock, which has excellent parallel cleavage so that it breaks into thin plates or pencil-like shapes.
Slate bar - The proper long-handled tool used to pry down loose and hazardous material from roof, face, and ribs.
Slickenside - A smooth, striated, polished surface produced on rock by friction.
Slip - A fault. A smooth joint or crack where the strata have moved on each other.
Slope - Primary inclined opening, connection the surface with the underground workings.
Slope mine – An underground mine with an opening that slopes upward or downward to the coal seam.
Sloughing - The slow crumbling and falling away of material from roof, rib, and face.
Solid - Mineral that has not been undermined, sheared out, or otherwise prepared for blasting.
Sounding - Knocking on a roof to see whether it is sound and safe to work under.
Spad – A spad is a flat spike hammered into a wooden plug anchored in a hole drilled into the mine ceiling from which is threaded a plumbline. The spad is an underground survey station similar to the use of stakes in marking survey points on the surface. A pointer spad, or sight spad, is a station that allows a mine foreman to visually align entries or breaks from the main spad.
Span - The horizontal distance between the side supports or solid abutments along sides of a roadway.
Specific gravity - The weight of a substance compared with the weight of an equal volume of pure water at 4 degrees Celsius.
Split - Any division or branch of the ventilating current. Also, the workings ventilated by one branch. Also, to divide a pillar by driving one or more roads through it.
Spoil - Material overlying a coal seam that is removed during a surface coal mining operation.
Squeeze - The settling, without breaking, of the roof and the gradual upheaval of the floor of a mine due to the weight of the overlying strata.
Steeply inclined - Said of deposits and coal seams with a dip of from 0.7 to 1 rad (40 degrees to 60 degrees).
Stemming - The noncombustible material used on top or in front of a charge or explosive.
Strike - The direction of the line of intersection of a bed or vein with the horizontal plane. The strike of a bed is the direction of a straight line that connects two points of equal elevation on the bed.
Stripping ratio – The unit amount of overburden that must be removed to gain access to a similar unit amount of coal or mineral material.
Stump - Any small pillar.
Subbituminous – Coal of a rank intermediate between lignite and bituminous.
Subsidence – The gradual sinking, or sometimes abrupt collapse, of the rock and soil layers into an underground mine. Structures and surface features above the subsidence area can be affected.
Sump - The bottom of a shaft, or any other place in a mine, that is used as a collecting point for drainage water.
Sumping - To force the cutter bar of a machine into or under the coal. Also called a sumping cut, or sumping in.
Support - The all-important function of keeping the mine workings open. As a verb, it refers to this function; as a noun it refers to all the equipment and materials--timber, roof bolts, concrete, steel, etc.--that are used to carry out this function.
Surface mine – A mine in which the coal lies near the surface and can be extracted by removing the covering layers of rock and soil.
Suspension - Weaker strata hanging from stronger, overlying strata by means of roof bolts.
Syncline - A fold in rock in which the strata dip inward from both sides toward the axis. The opposite of anticline.

T

Tailgate - A subsidiary gate road to a conveyor face as opposed to a main gate. The tailgate commonly acts as the return airway and supplies road to the face.
Tailpiece - Also known as foot section pulley. The pulley or roller in the tail or foot section of a belt conveyor around which the belt runs.
Tail section - A term used in both belt and chain conveyor work to designate that portion of the conveyor at the extreme opposite end from the delivery point. In either type of conveyor it consists of a frame and either a sprocket or a drum on which the chain or belt travels, plus such other devices as may be required for adjusting belt or chain tension.
Tension - The act of stretching.
Tertiary - Lateral or panel openings (e.g., ramp, crosscut).
Through-steel - A system of dust collection from rock or roof drilling. The drill steel is hollow, and a vacuum is applied at the base, pulling the dust through the steel and into a receptacle on the machine.
Timber - A collective term for underground wooden supports.
Timbering - The setting of timber supports in mine workings or shafts for protection against falls from roof, face, or rib.
Timber set - A timber frame to support the roof, sides, and sometimes the floor of mine roadways or shafts.
Tipple - Originally the place where the mine cars were tipped and emptied of their coal, and still used in that same sense, although now more generally applied to the surface structures of a mine, including the preparation plant and loading tracks.
Ton – A short or net ton is equal to 2,000 pounds; a long or British ton is 2,240 pounds; a metric ton is approximately 2,205 pounds.
Top - A mine roof; same as "back."
Torque wrench - A wrench that indicates, as on a dial, the amount of torque (in units of foot-pounds) exerted in tightening a roof bolt.
Tractor - A battery-operated piece of equipment that pulls trailers, skids, or personnel carriers. Also used for supplies.
Tram - Used in connection with moving self-propelled mining equipment. A tramming motor may refer to an electric locomotive used for hauling loaded trips or it may refer to the motor in a cutting machine that supplies the power for moving or tramming the machine.
Transfer - A vertical or inclined connection between two or more levels and used as an ore pass.
Transfer point - Location in the materials handling system, either haulage or hoisting, where bulk material is transferred between conveyances.
Trip - A train of mine cars.
Troughing idlers - The idlers, located on the upper framework of a belt conveyor, which support the loaded belt. They are so mounted that the loaded belt forms a trough in the direction of travel, which reduces spillage and increases the carrying capacity of a belt for a given width.
Tunnel - A horizontal, or near-horizontal, underground passage, entry, or haulageway, that is open to the surface at both ends. A tunnel (as opposed to an adit) must pass completely through a hill or mountain.

U

Ultimate analysis - Precise determination, by chemical means, of the elements and compounds in coal.
Undercut - To cut below or undermine the coal face by chipping away the coal by pick or mining machine. In some localities the terms "undermine" or "underhole" are used.
Underground mine – Also known as a "deep" mine. Usually located several hundred feet below the earth's surface, an underground mine's coal is removed mechanically and transferred by shuttle car or conveyor to the surface.
Underground station - An enlargement of an entry, drift, or level at a shaft at which cages stop to receive and discharge cars, personnel, and material. An underground station is any location where stationary electrical equipment is installed. This includes pump rooms, compressor rooms, hoist rooms, battery-charging rooms, etc.
Unit train – A long train of between 60 and 150 or more hopper cars, carrying only coal between a single mine and destination.
Universal coal cutter - A type of coal cutting machine which is designed to make horizontal cuts in a coal face at any point between the bottom and top or to make shearing cuts at any point between the two ribs of the place. The cutter bar can be twisted to make cuts at any angle to the horizontal or vertical.
Upcast shaft - A shaft through which air leaves the mine.

V

Valuation - The act or process of valuing or of estimating the value or worth; appraisal.
Velocity - Rate of airflow in lineal feet per minute.
Ventilation - The provision of a directed flow of fresh and return air along all underground roadways, traveling roads, workings, and service parts.
Violation - The breaking of any state or federal mining law.
Virgin - Unworked; untouched; often said of areas where there has been no coal mining.
Void - A general term for pore space or other reopenings in rock. In addition to pore space, the term includes vesicles, solution cavities, or any openings either primary or secondary.
Volatile matter - The gaseous part, mostly hydrocarbons, of coal.

W

Waste - That rock or mineral which must be removed from a mine to keep the mining scheme practical, but which has no value.
Water Gauge (standard U-tube) - Instrument that measures differential pressures in inches of water.
Wedge - A piece of wood tapering to a thin edge and used for tightening in conventional timbering.
Weight - Fracturing and lowering of the roof strata at the face as a result of mining operations, as in "taking weight".
White damp - Carbon monoxide, CO. A gas that may be present in the afterdamp of a gas- or coal-dust explosion, or in the gases given off by a mine fire; also one of the constituents of the gases produced by blasting. Rarely found in mines under other circumstances. It is absorbed by the hemoglobin of the blood to the exclusion of oxygen. One-tenth of 1% (.001) may be fatal in 10 minutes.
Width - The thickness of a lode measured at right angles to the dip.
Winning - The excavation, loading, and removal of coal or ore from the ground; winning follows development.
Winze - Secondary or tertiary vertical or near-vertical opening sunk from a point inside a mine for the purpose of connecting with a lower level or of exploring the ground for a limited depth below a level.
Wire rope - A steel wire rope used for winding in shafts and underground haulages. Wire ropes are made from medium carbon steels. Various constructions of wire rope are designated by the number of strands in the rope and the number of wires in each strand. The following are some common terms encountered: airplane strand; cablelaid rope; cane rope; elevator rope; extra-flexible hoisting rope; flat rope; flattened-strand rope; guy rope; guy strand; hand rope; haulage rope; hawser; hoisting rope; lang lay rope; lay; left lay rope; left twist; nonspinning rope; regular lay; reverse-laid rope; rheostat rope; right lay; right twist; running rope; special flexible hoisting rope; standing rope; towing hawser; transmission rope.
Working - When a coal seam is being squeezed by pressure from roof and floor, it emits creaking noises and is said to be "working". This often serves as a warning to the miners that additional support is needed.
Working face - Any place in a mine where material is extracted during a mining cycle.
Working place - From the outby side of the last open crosscut to the face.
Workings - The entire system of openings in a mine for the purpose of exploitation.
Working section - From the faces to the point where coal is loaded onto belts or rail cars to begin its trip to the outside.