Mining for Closure: Policies, practises and guidelines for sustainable mining and closure of mines

Surplus Rock or Waste Rock Rock that must be extracted to reach economic ore but does not contain significant commercial mineralization. Tailings Residue from metallurgical processing, mainly comprising finely ground rock. Tailings may contain process chemical residues. Tailings Retention System Holding areas for process wastes (tailings), also referred to as Tailings Storage Facili- ties, Tailings Dams, and Process Waste Storage Facilities. Topsoil The upper layer of soil which supports plant growth. Generally the layer containing nutrients, organic matter and seeds. Toxic Chemical A chemical compound that is fatal to hu- mans in low doses, or fatal to over 50% of test animals at stated concentrations. Units k = kilo (thousands – 10 3 ) as in kilogram (kg); G = giga (billions – 10 9 ) as in gigajoule (GJ); M = mega (mil- lions – 10 6 ) as in megajoule (MJ); T = tera (one million million or 10 12 ) as in terajoule (TJ); ppm = parts per mil- lion; ppb = parts per billion. VOCs Volatile Organic Compounds. Organic compounds (i.e. compounds of carbon) which evaporate at normal ambient temperatures. In addition to hydrocarbons (i.e. compounds of carbon and hydrogen) VOCs include oxy- genated compounds and compounds containing sulphur and halogens. Methane (CH 4 ) is treated separately by convention. VOCs contribute to the formation of ground level ozone through reaction with NO x and sunlight. VOCs can include toxics such as benzene and 1,3-buta- diene. Toxicity Measure of how harmful a substance is.

pass items such as the consequences of an event or set of circumstances and the likelihood of particular consequences being realised. Exposure pathways – that is, the manner in which people, property, or the biophysical, social, or cultural environment are exposed to a source of potential harm or a situation with a potential for harm are important is important when considering the likelihood of harm.

Harm Any damage to people, property, or the bio- physical, social, or cultural environment.

Likelihood A qualitative term covering both probability and frequency. The use of this termcan avoid problems caused by using frequency of defined events and prob- ability of specific outcomes interchangeably. Exposure pathways – that is, the manner in which people, prop- erty, or the biophysical, social, or cultural environment are exposed to a source of potential harm or a situation with a potential for harm are important is important when considering the likelihood of harm. Consequence(s) The intermediate or final outcome(s) of an event or situation. Consequence is a term that contains elements of the social as well as biophysical world thus system response factors such as stake- holder reactions (e.g. outrage) to an event or situa- tions are highly relevant here. Sulphuric Acid (H2SO4) Acid commonly used in industry for the refining of metals, solvent extraction of uranium and in the manufacture of chemicals and fertiliser. Hazard A source of potential harm or a situation with a potential for harm, thus a potential cause of harm.

Sulphur Dioxide (SO2) A gas that contributes to climate effects, acidification and other air quality problems.

Waste Rock see Surplus Rock

Salinization The accumulation of salts in soil that can eventually make the soil unable to support plant growth.

Water Table Upper surface of the zone of saturation, in which all available pores in the soil ands rock in the sub-sur- face are filled with water. Also called the phreatic surface.

Salinity Amount of various salts dissolved in a given vol- ume of water.

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MINING FOR CLOSURE