![AirPollutionSource](https://upload.wikimedia.org/wikipedia/commons/b/b9/AirPollutionSource.jpg)
A point source of pollution is a single identifiable source of
air
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...
,
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
,
thermal
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...
,
noise
Noise is unwanted sound considered unpleasant, loud or disruptive to hearing. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrations through a medium, such as air or water. The difference arise ...
or
light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...
pollution
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...
. A
point source
A point source is a single identifiable ''localised'' source of something. A point source has negligible extent, distinguishing it from other source geometries. Sources are called point sources because in mathematical modeling, these sources can ...
has negligible extent, distinguishing it from other pollution source geometries (such as
nonpoint source or
area source Area sources are sources of pollution which emit a substance or radiation from a specified area.
Air pollution
For example, area sources of air pollution are air pollutant emission sources which operate within a certain locale. The U.S. Environmen ...
). The sources are called ''point sources'' because in mathematical modeling, they can be approximated as a mathematical
point
Point or points may refer to:
Places
* Point, Lewis, a peninsula in the Outer Hebrides, Scotland
* Point, Texas, a city in Rains County, Texas, United States
* Point, the NE tip and a ferry terminal of Lismore, Inner Hebrides, Scotland
* Point ...
to simplify analysis. Pollution point sources are identical to other
physics
Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...
,
engineering
Engineering is the use of scientific method, scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad rang ...
,
optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviole ...
, and
chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...
point sources and include:
*
Air pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...
from an industrial source (rather than an airport or a road, considered 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 a ...
, or a forest fire, which is considered an area source, or
volume source)
*
Water pollution
Water pollution (or aquatic pollution) is the contamination of water bodies, usually as a result of human activities, so that it negatively affects its uses. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water ...
from factories, power plants, municipal
sewage treatment
Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable for discharge to the surrounding envir ...
plants and some farms (''see''
concentrated animal feeding operation
In animal husbandry, a concentrated animal feeding operation (CAFO), as defined by the United States Department of Agriculture (USDA), is an intensive animal feeding operation (AFO) in which over 1,000 animal units are confined for over 45 days a ...
). The U.S.
Clean Water Act
The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the responsibiliti ...
also defines municipal separate
storm sewer
A storm drain, storm sewer (United Kingdom, U.S. and Canada), surface water drain/sewer (United Kingdom), or stormwater drain ( Australia and New Zealand) is infrastructure designed to drain excess rain and ground water from impervious surface ...
systems and industrial
stormwater
Stormwater, also spelled storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow. Stormwater can soak into the soil ( infiltrate) and become groundwater, be stored on depressed la ...
discharges (such as
construction site
Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and com ...
s) as point sources.
*
Noise pollution
Noise pollution, also known as environmental noise or sound pollution, is the propagation of noise with ranging impacts on the activity of human or animal life, most of them are harmful to a degree. The source of outdoor noise worldwide is main ...
from a
jet engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term ...
* Disruptive
seismic
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other ...
vibration from a localized seismic study
*
Light pollution
Light pollution is the presence of unwanted, inappropriate, or excessive use of artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting, during the day ...
from an intrusive
street light
A street light, light pole, lamp pole, lamppost, street lamp, light standard, or lamp standard is a raised source of light on the edge of a road or path. Similar lights may be found on a railway platform. When urban electric power distribution ...
[{{cite web , url=https://www.nps.gov/subjects/nightskies/sources.htm , title=Light Pollution Sources , author= , website=Night Skies , publisher=U.S. National Park Service , access-date=2018-01-24]
*
Radio
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...
emissions from an interference-producing electrical device
See also
*
Nonpoint source pollution
Nonpoint source (NPS) pollution refers to diffuse contamination (or pollution) of water or air that does not originate from a single discrete source. This type of pollution is often the cumulative effect of small amounts of contaminants gathered ...
*
United States regulation of point source water pollution
Point source water pollution comes from discrete conveyances and alters the chemical, biological, and physical characteristics of water. In the United States, it is largely regulated by the Clean Water Act (CWA). Among other things, the Act requ ...
References
Pollution
Transboundary environmental issues