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Glossary

		
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Abandon

Used in reference to wells, abandonment is a process by which a well is filled and sealed from bottom to top

Abatement

The reduction or elimination of pollution.

Absorb

To take up or receive by chemical or molecular action.

Acclimation

Response by an animal that enables it to tolerate a change in a single factor (for example, temperature) in its environment.

Acid

A material with pH of less than 7.0

Acid Deposition

A comprehensive term for the various ways acidic compounds precipitate from the atmosphere and deposit onto surfaces. It can include: 1) wet deposition by means of acid rain, fog, and snow; and 2) dry deposition of acidic particles (aerosols).

Acid Rain

Rain with a higher than normal acid range. Caused when polluted air mixes with cloud moisture. The "acid" in acid rain comes from sulfur oxides and nitrogen oxides, products of burning coal and other fuels and from certain industrial processes. Acid rain can make lakes devoid of fish and damage human health and property.

Activated Carbon

A special carbon in powdered or grainy form that attracts and holds organic molecules. It is often used to remove dissolved contaminants.

Adaptation

Adjustments made by animals in respect of their environments. The adjustments may occur by natural selection, as individuals with favorable genetically acquired traits breed more prolifically than those lacking these traits (genotypic adaptation), or they may involve non-genetic changes in individuals, such as physiological modification (for example, acclimatization) or behavioral changes (phenotypic adaptation).

Adsorb

To gather a gas, liquid or dissolved substance on a surface

Adsorption

The clinging of molecules to the surface of particles; the process by which activated carbon removes contaminants from water.

Air Quality Standards

Federal and state government- prescribed levels of a pollutant in the outside air that cannot be exceeded during a specified period of time in a specified geographical area.

Air Stripping

Removing contaminants from water by enlarging the water's surface area and forcing air over it to evaporate volatile contaminants

Air Toxics

A category of substances in the air that are known or suspected of causing cancer or other health problems in humans, and for which a National Ambient Air Quality standard (NAAQS) does not exist (i.e. excluding ozone, carbon monoxide, PM-10, sulfur dioxide, nitrogen oxide).

Algae

Simple rootless plants that grow in bodies of water in relative proportion to the amount of nutrients available.

Algal Bloom

An unusual, sudden or excessive abundance of algae. Algal blooms can adversely affect water quality. See Also Hypereutrophic, 

Alkaline

Capacity of a lake to neutralize acid.

Alkalinity

Alkalinity is measured in mg/l as calcium carbonate (CaCO3). It represents a measure of a solution's ability to buffer or neutralize acids. Lakes located in areas of calcareous glacial till (common throughout central and southern Minnesota) will have higher alkalinity than lakes formed on non-calcareous bedrock (common in northeastern Minnesota). Water with alkalinity less than about 75 mg/L could be considered soft, 76-150 moderately hard, 151-300 hard, and greater than 300 very hard. Alkalinity has also been used as a basis for estimating sensitivity to acid precipitation. For this purpose, lakes with alkalinity values less than 5 to 10 mg/L could be considered potentially sensitive to acid precipitation based on current levels of deposition across Minnesota. At this point we have identified no "culturally acidified" lakes in Minnesota.

Ambient Air Quality

The state of quality of the air in the surrounding environment.

Ambient Ground Water Monitoring and Assessment

1. (EDA Ground Water) Ambient monitoring has two primary objectives. These are 1) to determine the status of the ground water resources, and 2) to identify trends in water quality over time. Between 1989 and 2001, the MPCA conducted ambient monitoring through the Ground Water Monitoring and Assessment Program (GWMAP). In 2003, the MPCA re-established an ambient monitoring effort.

Ambient Monitoring

Monitoring within natural systems (lakes, rivers, estuaries, and wetlands) to determine existing conditions.

Ammonia (NH3-N)

an inorganic form of nitrogen, is contained in fertilizers, septic system effluent, and animal wastes. It is also a product of bacterial decomposition of organic matter. Ammonia NH3-N (NH3-N) becomes a concern if high levels of the un-ionized form are present. In this form NH3-N can be toxic to aquatic organisms. The presence of un-ionized ammonia is a function of the NH3-N concentration, pH, and temperature. Conversion of NH3-N to nitrite nitrogen by nitrification requires large quantities of oxygen which can kill aquatic organisms due to the lowered dissolved oxygen concentrations in water. NH3-N concentrations are reported in mg/L NH3-N.

Animal Units

A unit of measure used to compare different types of animals. This measure is calculated by multiplying the number of animals by their average weight and dividing by 1000: AU = (w * n)/1000 where w is the average weight of the animals and n is the number of animals.

Anthropogenic

Caused by human activity.

Appearance

1. (CSMP) Each day that you sample, please record the one number that best describes the appearance of stream water within one meter of your sampling site.

1A = Clear - crystal clear, transparent water

1B = Tea-colored - transparent water, which has been colored by dissolved organic matter from upstream bogs or wetlands

2 = Cloudy - not quite crystal clear; cloudy white, gray or light brown

3 = Muddy - cloudy brown due to high sediment levels

4 = Green - due to algae growth; indicative of excess nutrients released into the stream

5 = Muddy AND Green - a combination of cloudy brown from high sediment levels and green from algae growth

Aquatic Assemblage

An organism group of interacting populations in a given waterbody, for example, fish assemblage or a benthic macroinvertebrate assemblage.

Aquatic Biota

Collective term describing the organisms living in or depending on the aquatic environment.

Aquatic Community

Association of interacting assemblages in a given waterbody, the biotic component of an ecosystem. See Also Aquatic Assemblage, 

Aquatic Life

Plants or animals living in water.

Aquatic Life Use

A beneficial use designation in which the waterbody provides suitable habitat for survival and reproduction of desirable fish, shellfish, and other aquatic organisms.

Aquatic Recreation

Formerly referred to as "swimmable use" support, this use support classification considers not only swimming, but also wading, aesthetics, and other related uses. The various classes of full, partial and non support are defined in the text of the Lake Water Quality Assessment Report (2008). (http://www.pca.state.mn.us/water/lakequality.htm l#reports)

Aquifer

An underground layer of sand, gravel or rock that stores or conveys water below the surface of the soil.

Aquitard

An underground bed or layer of soil, rock or clay that is too dense to allow easy passage of water.

ARAR

Applicable, relevant and appropriate requirements -- federal, state and local regulations that apply to cleanup options.

Area Sources

Area sources are smaller sources of air emissions that are not required to submit criteria pollutant data to the MPCA. Examples of area sources include gas stations, dry cleaners and auto body shops. Individually, these sources do not emit much air pollution, but collectively release large amounts of one or more toxic air pollutants.

Artesian

Ground water under sufficient pressure to rise above the top of the aquifer containing it.

Asbestos

An incombustible, chemical-resistant, fibrous mineral form of impure magnesium silicate. Prolonged, inhalation of asbestos can lead to asbestosis -- a chronic, progressive lung disease.

Ash

In combusion, solid residue that remains after waste has been completely burned.

Assemblage

An association of interacting populations of organisms in a given waterbody. Examples of assemblages used for biological assessments include: algae, amphibians, birds, fish, reptiles and amphibians, macroinvertebrates (insects, crayfish, clams, snails, etc.), and vascular plants.

Atmosphere

The body of air surrounding the earth. The body of air surrounding the earth.

Attainment Area

A geographic area in which levels of a criteria air pollutant meet the health-based primary standard (national ambient air quality standard, or NAAQS) for the pollutant. An area may have an acceptable level for one criteria air pollutant, but may have unacceptable levels for others. Thus, an area could be both attainment and nonattainment at the same time. Attainment areas are defined using federal pollutant limits set by the U.S. Environmental Protection Agency.

Attribute

A measurable component of a biological system.