Glossary of terms

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Acid rain: Gases such as sulphur dioxide and oxides of nitrogen that undergo chemical reactions in the atmosphere and are transformed to sulphate and nitrate particles (acid gas precursors) as well as gaseous sulphuric and nitric acids (acid gases). These acids can be deposited with rain and adversely affect vegetation and aquatic ecosystems.

Adsorbed phase fuel: When hydrocarbons enter soil profiles, some of the hydrocarbons attach to the soil and rock particles.

Ammonium nitrate: A compound of nitrogen, hydrogen and oxygen (NH4NO3) that is used in the manufacture of explosives and fertiliser.

Aquifer: A rock formation that contains groundwater which may be able to be extracted for use.

Ballast water: Water carried in tanks to maintain stability when a ship is lightly loaded; normally discharged to the sea when the ship is loaded with cargo.

Baseline information: Information relating to a specific time or defined area of land or water, from which trends or changes can be assessed; often a key component of environmental impact and risk assessments.

Biodiversity: The variety of all life forms; plants, animals and micro organisms, the genes they contain and the ecosystems they form. Often considered at three levels: genetic, species and ecosystem diversity.

Bleeder: A piece of equipment that allows liquid or gas to escape safely and in a controlled manner.

Chlorofluorocarbons (CFCs): Synthetic carbon compounds containing chlorine and fluorine; used in various industrial processes and as refrigerants. CFCs deplete ozone in the stratosphere and are powerful greenhouse gases.

Cleaner production: An overall approach to business management that reduces the use of energy and material resources, and minimises waste and pollution.

Climate change: A change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods. (source United Nations Framework Convention on Climate Change) Coal seam methane: Methane gas that is contained within coal beds.

Co-generation: Process by which waste heat is captured and used to produce electricity.

Condensate: Hydrocarbons in gaseous form in a geologic reservoir but which condense to liquid at surface pressures and temperatures when extracted.

Contaminated sites: Areas of land that have been subject to contaminants so that the soil and/or groundwater contains contaminants which are at levels above naturally occurring background concentrations, and which may cause potential harm to human health and the environment.

Dieback:  dieback can refers to impairment (stress and/or death) of forest adjacent to the river due to increased overbank flooding and deposition of additional sediment load.

Dioxins: Refers to polychlorinated dibenzo para dioxins (PCDDs) and polychlorinated dibenzo furans (PCDFs), of which there are many isomers of varying toxicity. These halogenated compounds are resistant to degradation resulting in their persistence in the environment.

Dissolved oxygen: The oxygen which is dissolved in water and is necessary for aquatic organisms to live.

Dissolved phase fuel/hydrocarbons: In the context of soil and ground water contamination, some hydrocarbons can be in a dissolved form within groundwater.

Ecology: The scientific study of living organisms and their relationships with one another and the environment.

Ecosystem: A dynamic complex of plant, animal and micro organism communities and their non living environment interacting as a functional unit.

Effluent: A discharge or emission of waste liquid or sludge.

Energy intensity: The amount of energy per unit of product or activity (usually expressed as gigajoules per tonne).

Environmental impact assessment (EIA): A methodology to assess the potential impact of a project or proposal upon the environment; the process is often required by law, but is also undertaken on a voluntary basis as a component of good environmental management practice.

Environmental impact statement (EIS) is the document produced by the EIA study.

Environmental management system (EMS): Organisational structure, responsibilities, policies, practices, procedures, processes and resources for implementing and maintaining environmental management.

Exceedence: An event where concentrations of contaminants or other relevant operating parameters are outside of a set range of operating conditions or licence limits.

Flaring: The practice of burning off waste gas or oil during testing or production processes.

Free phase fuel/hydrocarbon: In the context of soil and groundwater contamination, hydrocarbons that are not dissolved or absorbed but in a liquid physical phase separate from water or air.

Fugitive emissions/dusts: Emissions of gases or dusts which escape during the processing and handling of materials other than through a designated process emission point.

Greenhouse gases: Naturally occurring and man made trace gases including water vapour, carbon dioxide, methane, nitrous oxide, ozone and CFCs which trap heat in the atmosphere, keeping the surface of the Earth warmer than it would otherwise be.

Greenhouse intensity: The amount of greenhouse gases released per unit of activity or output.

Halons: Inert gases used in some fire extinguishing systems. Halons are also ozone depleting substances.

Hazardous waste: A waste which has the potential through its production, transport, storage, handling, use or disposal to harm the health of people or the environment, and as such requires special precautions and practices.

Heavy metal: Ametallic element with relatively high atomic mass, such as lead, cadmium, arsenic and mercury; which are generally toxic to plant and animal life in relatively low concentrations.

Injection wells: Wells that are used to inject either liquid or gas into a reservoir to improve recovery of hydrocarbons.

ISO 14001: International Standards Organisation specification for environmental management systems.

Life cycle analysis (LCA): A process to study the environmental aspects and potential impacts throughout a product’s life, from raw material, through production, use and disposal.

Ozone depleting substance (ODS): A group of chemical substances which have been linked to the reduction of stratospheric ozone providing a protective layer shielding Earth from ultraviolet radiation. Known ODSs include halons, chlorofluorocarbons, hydrochlorofluorocarbons and hydrofluorocarbons.

Particulates: Very small pieces of solid or liquid matter, such as soot, dust or mist.

Pathogens: Micro organisms which are parasitic, cause disease in, or otherwise affect organisms.

Photochemical smog: Air pollution caused by chemical reactions among various substances and pollutants in the atmosphere in the presence of sunlight; ozone is a major constituent.

Phytoplankton: Small, water living organisms, such as algae and diatoms, that use photosynthesis to produce energy.

Rehabilitation: Treatment of a disturbed area to achieve a land form and level of productivity and stability consistent with an agreed post operation land use.

Remediation: Returning something, usually land and groundwater, to a standard suitable for an agreed use.

Risk assessment: Determines the relative risk of a potential environmental impact in terms of the severity of environmental impact and likelihood of the impact occurring.

Shoals: Steep sided underwater calcium carbonate banks, whose tops support shallow water ecosystems.

Suspended solids: Any solid substance present in water in an undissolved state, usually contributing directly to turbidity.

Toxicity: Measure of how poisonous a substance is to humans and other organisms.