Area sources are sources of pollution which emit a substance or radiation from a specified area.Examples of area sources include gas stations, dry-cleaners, print shops, autobody shops, furniture manufactures, and home sources such as wood stoves, pesticides, and cleaners. Area sources contribute to 26 percent of all man-made air toxic emissions according to EPA estimates.

Air pollution

For example, area sources of

air pollution Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...

are air pollutant emission sources which operate within a certain locale. The U.S. Environmental Protection Agency has categorized 70 different categories of air pollution area source.

Locomotives A locomotive is a rail vehicle that provides the motive power for a train. Traditionally, locomotives pulled trains from the front. However, push–pull operation has become common, and in the pursuit for longer and heavier freight train ...

operating on certain linear tracks are examples of a

line source A line source, as opposed to a point source, area source, or volume source, is a source of air, noise, water contamination or electromagnetic radiation that emanates from a linear (one-dimensional) geometry. The most prominent linear sources ...

, whereas locomotives operating within a railyard are an example of an area source of pollution. Other area sources of air pollution are: * Multiple flue gas stacks within a single industrial plant * Open burning and

forest fires A forest fire A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a bushfire ( in Au ...

Evaporation Evaporation is a type of vaporization that occurs on the Interface (chemistry), surface of a liquid as it changes into the gas phase. A high concentration of the evaporating substance in the surrounding gas significantly slows down evapora ...

losses from large spills of volatile liquids

Water pollution

Water pollution Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...

manifestations of an area source—often called nonpoint source pollution—include: *

Surface runoff Surface runoff (also known as overland flow or terrestrial runoff) is the unconfined flow of water over the ground surface, in contrast to ''channel runoff'' (or ''stream flow''). It occurs when excess rainwater, stormwater, meltwater, or other ...

of fertilizer or pesticides from rainfall or irrigation water * Widespread failure of a

septic drain field Septic drain fields, also called leach fields or leach drains, are subsurface wastewater disposal facilities used to remove contaminants and impurities from the liquid that emerges after anaerobic digestion in a septic tank. Organic materials in ...

* Dispersal of an

oil spill An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially the marine ecosystem, due to human activity, and is a form of pollution. The term is usually given to marine oil spills, where oil is released into th ...

in a water body. In the 1950s or earlier hydrology transport models appeared to calculate

surface runoff Surface runoff (also known as overland flow or terrestrial runoff) is the unconfined flow of water over the ground surface, in contrast to ''channel runoff'' (or ''stream flow''). It occurs when excess rainwater, stormwater, meltwater, or other ...

, primarily for flood forecasting. Beginning in the early 1970s computer models were developed to analyze the transport of runoff carrying

water pollutant Water pollution (or aquatic pollution) is the contamination of water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. W ...

s, which considered dissolution rates of various chemicals, infiltration into soils and ultimate pollutant load delivered to receiving waters. One of the earliest models addressing chemical dissolution in runoff and resulting transport was developed in the early 1970s by the

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent agency of the United States government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on De ...

.C. Michael Hogan, Leda Patmore, Gary Latshaw, Harry Seidman et al. 1973 This

computer model Computer simulation is the running of a mathematical model on a computer, the model being designed to represent the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determin ...

formed the basis of much of the regulatory framework that led to strategies for water pollution control via

land use Land use is an umbrella term to describe what happens on a parcel of land. It concerns the benefits derived from using the land, and also the land management actions that humans carry out there. The following categories are used for land use: fo ...

and chemical handling techniques. People produce so much trash that half of it goes in water sources.

References

* C. Michael Hogan, Leda Patmore, Gary Latshaw, Harry Seidman et al. 1973. ''

Computer model Computer simulation is the running of a mathematical model on a computer, the model being designed to represent the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be determin ...

ing of pesticide transport in soil for five instrumented watersheds'', U.S. Environmental Protection Agency Southeast Water laboratory, Athens, Ga. by ESL Inc., Sunnyvale, California * Arnold W. Reitze, J. B. Shapiro and Maurice C. Shapiro. 2005. ''Stationary Source Air Pollution Law'', Published by Environmental Law Institute, 500 pages ,

Line notes

{{reflist Pollution

Air pollution

Water pollution

See also

References

Line notes