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Without oxygen.

Carbon (C)

A nonmetallic element. It occurs in all organic compounds. All life on Earth depends on carbon.

Carbon cycle

The process by which carbon moves from the atmosphere into the Earth and its organisms and then back again.

Carbon dioxide (CO2)

A colourless, odourless non-combustible gas with the formula CO2 that is present in the atmosphere. It is formed by the combustion of carbon and carbon compounds (such as fossil fuels and biomass) and by respiration, which is a slow combustion in animals and plants, and by the gradual oxidation of organic matter in the soil.

Closing the loop 

Means waste is collected and made into new products e.g. aluminium cans recycled to make new aluminium cans. The symbol for recycling is three green arrows going around in a circle which means closing the loop.


Means to put things together very closely. To compact something means to squash it up.


Once things are squashed up they are said to be compacted.


Is the process of organic material decomposing into compost which is then used to improve soil.


A person who buys things (goods or services) for themselves.


Rotting or decaying. It is the process of plant and/or animal material breaking down by the action of bacteria and fungi.


Packed or crowded closely together.


Designed to be thrown away after use.


Becoming part of a liquid e.g. sugar dissolves in water.


Something that is released into the environment e.g. smoke from a fire, fumes from a car.

Generation plant 

All the machinery that produces electricity. At Redvale this includes a gas turbine that changes energy in methane gas to mechanical energy and generators that converts that energy into electricity.


A machine that changes one type of energy into another. At Kate Valley a generator changes mechanical energy into electricity.

Greenhouse effect 

The effect of the Earth's atmosphere, due to certain gases, in trapping heat from the sun; the atmosphere acts like a greenhouse.

Greenhouse gases

Gases that trap the heat of the sun in the Earth's atmosphere, producing the greenhouse effect. The two major greenhouse gases are water vapour and carbon dioxide. Lesser greenhouse gases include methane, ozone, chlorofluorocarbons, and nitrogen oxides.

Hooklift bins 

Large sealed containers (bins) that are picked up by a hooklift crane.

Hooklift cranes  

Cranes that have an extended arm with a hook designed to fit into the end of hooklift bins.


A term used to describe the power of an engine. 1 hp is equal to 746 watts. A 200hp engine (a powerful car) is the same as 147 kilowatts.

Impact (as a noun) 

The effect that something has on the environment e.g. rats have had a serious impact on the birds in the forest.


Happening near the side of the road or footpath (near the kerb).


Water that drains (or leaches) down through the soil. Often leachate has things dissolved in it that makes it poisonous.

Life cycle thinking 

Thinking about all of the impacts that a product has through its life cycle (from cradle to grave). The life cycle might include: extraction of raw materials, product manufacturing, packaging and distribution, product consumption, end of life. At each life cycle stage, there is resource and energy consumption and impacts created (social, economic and environmental).


The fabric at the bottom of the landfill that separates the rubbish from the ground. Any water that leaches down through the rubbish gets to the liner and drains away to be collected.

Methane (CH4)

A colourless, odourless flammable gas which is the main part of natural gas. Methane can be used as a fuel. It forms from the decomposition of organic material.


A word for a rubbish heap. The word is used to describe rubbish heaps created by people a long time ago e.g. early Maori created middens that contain shells, bones and broken tools that are very interesting for archaeologists.


To check the progress of something over a period of time (e.g. a year). Environmental monitoring often involves sensors such as water temperature or pH sensors, and this information being recorded and possibly sent to another location e.g. by telemetry.

National grid 

The network of high voltage power lines that go from power stations to electricity users such as people in houses and factories.

Organic waste

Organic waste is material that is biodegradable and comes from either a plant or animal.




Anything that is or has been living e.g. plant or animal material.


Anything used to wrap and protect a product.


Preparing something for processing. E.g. filtering out the muck from used engine oil before it is refined into reusable oil.


Something that is manufactured (created through a series of steps). E.g. packets of biscuits, smart phones and light bulbs are all products.


To restore something to its original condition e.g. the rehabilitation of a forest that had been badly affected by possums.


The treatment of material taken from the waste stream to make new materials or products.


What is left after other things have been taken away. Residual waste is what is left after everything that can be recycled, reused, recovered has been taken away.

Resource Management Act (RMA) 

The RMA is an act of parliament passed in 1991 that governs how the New Zealand environment (land, air and water) is managed. Councils have to make rules that comply with the RMA. A key part of the RMA is that it is based on the principle of sustainability.


This word means that an activity is able to be continued forever. E.g. fishing can be sustainable so long as we leave enough fish in the sea to breed.


The process of recording and transmitting (sending out) the readings of an instrument.



Transfer stations/resource recovery 

A place where waste is collected and sorted before being transferred to recycling plants or the landfil.