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Towards a Common Language
July 2008
We’ve try to minimize the technical jargon in our communications, but some terminology is unavoidable. The following are definitions of some of the terms we commonly use in our newsletters and public documents. If there are other terms you would like explained, just let us know by completing “We’d Like to Hear From You” on the back page of this article.
Acidity: A chemical characteristic of a liquid that indicates how strongly it will react with other chemicals by donating a proton or accepting electrons. Examples of acidic liquids include vinegar, fruit juices and carbonated beverages.
Alkalinity: A chemical characteristic of a liquid that indicates how strongly it will react with other chemicals by donating electrons or accepting a proton. Examples of alkaline liquids include ammonia and detergents.
Becquerel (Bq): A measurement of the rate at which unstable atoms break down. One Bq equals one atomic breakdown per second. One Bq/L of radium-226 means that one atom of radium-226 in a litre of water breaks down each second.
Berm: A low-height (less than one metre) man-made structure constructed to hold tailings or water.
Canadian Nuclear Safety Commission (CNSC): The federal agency responsible for regulating all nuclear facilities, including uranium tailings waste management operations.
Dam: A man-made structure engineered to hold tailings or water. Permeable dams are made of rock and sand to allow water – but not tailings – to pass through. Impermeable dams have clay centres surrounded by sand and rock. This prevents water from passing through.
Effluent: Surface water and seepage collected from tailings management areas that is directed to the treatment plants.
Effluent Treatment: The addition of lime and barium chloride to surface water and seepage collected from tailings management areas. This process neutralizes acidity and removes metals and radionuclides. The water is later released to a settling pond, where treatment solids settle out and clear. The treated water is then discharged.
mSv(Millisievert) : The unit used to measure the amount of radiation absorbed by an object or living creature. The average Canadian receives 2.4 mSv of radiation annually from natural sources. Millisieverts measure the biological significance of “radiation dose.”
Ontario Drinking Water Standards: Ontario’s Ministry of the Environment has established both health-related and aesthetic standards for drinking water. The maximum allowable concentration (MAC) is the amount of a given substance in water (usually measured in mg/L) that scientific studies have shown will protect human health. Aesthetic objective (AO) is the amount of a given substance in water that does not result in an unacceptable odour, colour or taste.
Parameter: A term often used synonymously with “compound,” parameters may occur naturally or as a result of mining activities. Parameters commonly found in the Serpent River Watershed include: sulphate, radium, uranium, iron, manganese, barium and cobalt.
pH: A measure of the acidity and alkalinity of liquids. A pH of 7 is neutral. Any measure less than 7 shows increasing acidity. The pH of lakes and rivers normally varies from 6 to 8. Rainwater has a pH of 4.5 to 7.
Provincial Water Quality Objective (PWQO): The amount of a given chemical in water (usually measured in mg/L) that scientific studies have shown does not harm aquatic life. The Ontario Ministry of the Environment sets these objectives for a variety of chemical elements to ensure the ecological health of our lakes and rivers.
Radiation: Energy that takes the form of waves or can be carried by energetic particles. Light and heat from the sun are common forms of radiation.
Radiation Dose: The amount of energy absorbed by matter when radiation passes through it.
Radionuclide: All matter is composed of atoms. Unstable atoms that release energy when they break down to form new atoms are called radionuclides. The new atoms may be different elements or isotopes – different forms of the original atoms.
Radium-226: A naturally occurring element created by the breakdown of uranium. Radium-226 was not removed during milling at Elliot Lake sites. There are only about 20 pounds of radium-226 in all of the 150 million tons of tailings in the Elliot Lake area.
Settling Pond: An area downstream of a treatment plant where where treatment solids settle to the bottom and treated water is discharged. Clear, treated water is released to the environment from settling ponds.
Siphon: A pipeline that uses gravity to move water from a body of water over a topographic high (e.g. the top of a dam or a hill). The body of water at the inlet of the pipeline must be at a higher elevation than the outlet of pipeline.
Slurry: A mixture of fine grained particles (e.g. sand or smaller) and water that enables the solid material to be moved through a pipeline like a liquid.
Sump: A small pond or basin used to collect water before it is pumped or released to an outflow structure. In some cases, the water level in the sump is used to monitor and control the rate of pumping or release of water.
Tailings: Crushed rock the consistency of beach sand. Tailings are what remain when rock containing uranium (or other desirable minerals) is ground up and the uranium has been removed.
Tailings Management Area (TMA): An area used to permanently contain tailings. TMAs are generally located in natural rock basins. Dams are constructed in low-lying areas of TMAs to ensure containment of tailings.
Treatment Solids: Remaining material after water collected from the tailings management areas is treated with lime to neutralize acidity and remove metals and radionuclides.
Uranium: A naturally occurring element which, when purified and concentrated, is used as fuel to generate nuclear power. The amount of uranium in the rocks mined in the Elliot Lake area was 0.10 percent. Since 95 percent to 98 percent of the uranium was removed during milling, the amount remaining in the tailings is less than 0.005 percent, or the equivalent of half a teaspoon of sand in a 45-gallon drum.
Weir: A concrete, wooden or plastic structure that channels water through an opening where the flow can be measured. The structure can be installed in a stream or a lake outlet and may be included as part of a dam. Some weirs include stop logs or other mechanisms to control the water flow.
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