HOW TO MANAGE NORM DURING A DECOMMISSION
WHAT IS NORM ? Every mineral and raw material contain what are called radionuclides of natural origin . While the vast majority of human activity involving these minerals and raw materials is of no cause for radiative concern , some activities do increase the exposure to ionising radiation . This is known by the acronym NORM .
Burning coal , making and using fertilisers and oil and gas production are all common cases which result in NORM , meaning processes must be in place to deal with the heightened exposure . The term NORM also exists to distinguish ‘ natural radioactive material ’ from anthropogenic sources of radioactive material , such as those produced by nuclear power , where the radioactive properties of a material is the reason for human interest .
As more NORM hazards have been identified over time , industries have become increasingly subject to monitoring and regulation , although the World Nuclear Association says there is little consistency among these regulations , meaning what is considered as radioactive waste in one country may not be in another .
“ Anyone maintaining an oil or gas facility needs to be aware of the fact that even if NORM is not detected during or after the shutdown of a plant , it should still be regarded as a long-term recurring issue ”
In terms of oil and gas production , the extent of NORM depends largely on the radioactivity of the reservoir rock and salinity of water co-produced from the wells . The more saline in the water , the more NORM is likely to be found . This means that older wells tend to exhibit higher degrees of NORM than their younger counterparts .
Fracking is a gas extraction technique which can lead to significant release of NORM in some geological environments . Generally , however , external exposure to NORM in the oil and gas industry is low enough not to require protective measures to make sure workers stay under their annual limits .
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