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The information contained on this page is
subject to the disclaimer.
© copyright WMC Resources Ltd 2005
Why is "water usage" an important measure?
Water resources are valuable because they are fundamental to any human or commercial activity and because they are scarce.
What is the definition of "total water use and high quality water use"?
"Total water use" - includes all water we use, whether it be good quality, saline or hyper saline. It excludes water extracted as part of dewatering activities which is not used for mining purposes or in mineral processing.
"High quality water use" - includes only that water containing less than 5,000mg/L total dissolved solids. Its high quality means that it could have been used for agricultural or pastoral use. High quality water is supplied either from a public utility or from WMC managed groundwater and surface water collections.
A "megalitre" is a unit of volume equal to a million litres.
Why is "energy usage" an important measure?
The energy we use is generally from non-renewable sources. Our energy use therefore depletes these resources and generally results in the emission of greenhouse gases. We are a relatively energy intensive industry. Energy is expensive and we seek to minimise our use of energy as best we can.
What is the definition of "energy use"?
The unit of measure for energy is joule. A joule is the amount of energy needed to heat one gram of water by one degree centigrade. A "terajoule" is equal to a million million joules.
We report the energy we use in our operations associated with the use of electricity, natural gas, LPG and liquid fuels such as diesel and petrol. We convert the fuels used into their energy equivalents using standard conversion factors.
For electricity generation we report the energy content of the primary fuel source only where we operate or lease the power generation facility. Where electricity is purchased from a third party we only report the energy of the electricity that is actually supplied to our operation.
Why is "greenhouse gas emissions" an important measure?
Available evidence indicates that the emission of greenhouse gases may contribute to the greenhouse effect and to global warming. We generate greenhouse gases through the use of energy (i.e. use of purchased electricity and combustion of fossil fuels) and in the production of ammonia in our Queensland Fertilizer Operation. We are a relatively energy intensive industry and seek to minimise our energy use and associated greenhouse gas emissions as best we can within the limits of available and cost effective technology.
What is the definition of a "greenhouse gas"?
A "greenhouse gas" is any gas that may contribute to the greenhouse effect. This includes carbon dioxide, methane and nitrous oxide.
A tonne is a unit of mass equal to a thousand kilograms. Each greenhouse gas has a different impact in global warming. The impact of all greenhouse gases are aggregated in terms of the equivalent amount of carbon dioxide (CO2 equivalent) required for the same impact. Methane, for example, has 21 times the greenhouse effect of carbon dioxide - so 48 kilograms of methane is one tonne CO2 equivalent.
We report both direct and indirect emissions (eg. emission associated with the generation and transmission of purchased electricity and product transport between our facilities).
Why is "sulphur dioxide emissions" an important measure?
Sulphur dioxide is a priority air pollutant. High levels of sulphur dioxide in the air can cause adverse health effects to people and can cause damage to vegetation. Sulphur dioxide in the air can also cause "acid rain" - an effect where the sulphur dioxide dissolves in the rain forming dilute sulphuric acid.
What is the definition of "sulphur dioxide emissions"?
Sulphur dioxide emissions include measured or estimated point source stack emissions as well as estimated emission arising from fuel combustion.
A "tonne" is a measure of mass equal to a thousand kilograms.
Why is "disturbed land" an important measure?
Undisturbed land is environmentally valuable because it provides an important habitat for native species and contributes to maximising biodiversity.
Our operations generally lead to the disturbance of land. We seek to keep this disturbance to a minimum and aim to return the land to its original state as much as practical through rehabilitation as soon as practicable once we have determined that we have no further need to access the land.
What is the definition of "disturbed land"?
"Disturbed land at years start" is the total area of land that has been intentionally cleared, or partially cleared, of vegetation which has not been rehabilitated
"Land disturbed during the year" is the total area of land that has been intentionally cleared, or partially cleared, of vegetation during the reporting period.
"Rehabilitation" is the process by which disturbed land is returned as much as practicable to its original state.
Phase one of the rehabilitation process is "Land rehabilitation earthworks". It is the area of disturbed land on which earthworks have been completed to develop a profile which is stable and will minimise erosion. Top-soil stripped during disturbance is applied to support vegetation establishment.
Phase two of the rehabilitation process is "Land rehabilitation revegetation" It includes spreading seeds and/or planting of selected plant species seedlings of appropriate vegetation.
"Land rehabilitated during the year" area of disturbed land on which both phase one and two of the rehabilitation process has been completed. Rehabilitation monitoring is undertaken as part of phase three to determine the success of rehabilitation against agreed criteria.
Why is "tailings management" an important measure?
Tailings are fine grained materials produced from the processing of mineral ores and are a major by-product of the mining industry. Tailings storage facilities are generally large and can have a significant impact on visual amenity.
Once closed, tailings storage facilities undergo rehabilitation equivalent to that undertaken for other disturbed land.
What is the definition of "tailings"?
"Operating tailings facilities at years start" is the estimated mass of tailings stored and total area of land occupied by tailings storage facilities at the start of the reporting period.
"Tailings production" is the estimated mass of tailings produced during the reporting period.
"New tailing facilities opened" is the area of land occupied by tailings storage facilities brought into operation during the reporting period.
"Tailings facilities closed" is the total area of tailings storage facilities which were closed during the reporting period. Rehabilitation of the facility may still be required.
"Closed tailings facilities at the years end" is the estimated mass of tailings stored in closed tailings storage facilities as well as the total area of land occupied by closed tailings storage facilities.
"Operating tailings facilities storage at year's end" is the estimated mass of tailings stored as well as the total area of land occupied by tailings storage facilities at the end of the reporting period.
A "tonne" is a unit of mass equal to one thousand kilograms.
A "hectare" is a unit of land area equal to ten thousand square metres.
(LT+MT)IFR means the combined lost time and medical treatment injury frequency rate.
The injury rate is an important measure of our safety performance as it captures all serious injuries, or those which require attention beyond the scope of normal first aid.
Why is lost days and severity rate an import measure?
The lost days and severity rates are an important measure as they reflect the duration of a persons incapacity to work.
