Acidic (a-SID-ick): The condition
of water or soil which contains a sufficient amount of acid substances
to lower the pH below 7.0.
Acanthamoeba: A type of protozoa found in soil and fresh water, which may cause infection in humans and animals.
ADWG: Australian Drinking Water
Guidelines, published by the National Health and Medical Research Council
(NHMRC).
Aeration: Mixing or agitation
of wastewater, allowing for the mixture of air (oxygen) with the wastewater.
Alarm: A visual and/or audible warning of a problem, condition or incident.
Alert: A notification that some change has occurred in a process which needs to be brought to an operator's attention.
Algae: Type of simple aquatic plants.
Algal bloom: An extensive
growth of algae in a body of water (river, lake, dam), usually as a
result of high nutrient levels in the water.
Alkali (AL-ka-lie): Various soluble salts,
principally of sodium, potassium, magnesium, and calcium, that have the property
of combining with acids to form neutral salts and may be used in chemical water
treatment processes.
Alkaline (AL-ka-LINE): The condition
of water or soil which contains a sufficient amount of alkali substances to raise the
pH above 7.0.
Alkalinity (AL-ka-LIN-it-tee):The capacity of
water to neutralise acids. This capacity is caused by the water's content of carbonate,
bicarbonate, hydroxide, and occasionally borate, silicate, and phosphate. Alkalinity is
expressed in milligrams per litre of equivalent calcium carbonate. Alkalinity is not the
same as pH because water does not have to be strongly basic (high pH) to have a high alkalinity.
Alkalinity is a measure of how much acid can be added to a liquid without causing a great change in pH.
Aquifer: A water-containing soil or rock layer below
the land surface through which water can move.
Audit trail: A sequence of records showing all activities, interactions, warnings, alerts, alarms, incidents and comments associated with the running of an overall process.