(STEP) See pressure sewer.

The collection of a series of separate air or water samples at timed intervals.

The various transitions in the orderly and predictable changes in a biological community from the pioneer community stage to the climax stage. See succession.

Testing the components of a model to determine the change in the model’s prediction based on the relative change in each component; can be used to decide which component measurements/estimates should be emphasized in the application of the model, that is, which values have most effect on the predicted outcome.

An allergic response to a chemical substance that is preceded by a sensitizing exposure. Once an individual is sensitized to a substance, quite low doses can elicit an adverse response affecting the skin or respiratory system. See allergen.

Liquids and/or solids pumped out during the periodic cleaning of a domestic septic tank.

Apparatus used to treat sanitary waste from an individual residence or business. Such systems range from a simple underground tank with the overfl ow connected to a system of underground drain pipes (septic tank) to sophisticated mechanical units equipped with aeration devices and disinfection capability. See pressure sewer; primary treatment; secondary treatment.

An organism that has the capacity to satisfy its requirements for carbon-containing nutrients by the fixa-tion, reduction, and incorporation of carbon dioxide from the environment. Green plants, which derive their energy from sunlight through the process of photosynthesis, represent a major group of autotrophic organisms. Compare heterotroph.

A buried tank used to treat domestic wastes. The sanitary waste from a household is deposited and retained in a covered tank to allow solids to settle to the bottom and to provide an environment for the decomposition of organic components by anaerobic bacteria. The liquid effl uent that fl ows from the tank is [...]

(STEF) See pressure sewer.