Abstract
This paper examines the challenges associated with NORM disposal for the offshore oil and gas industry in Australia. This paper will address the Australian regulatory context and ‘textbook’ disposal alternatives and identify the approved avenues for disposal. Whilst this paper will reflect on how NORM is managed to minimise personnel and public exposure to NORM, in essence this paper will review regulatory considerations required for NORM disposal. This paper attempts to answer the question of, where to now with NORM disposal in Australia?
The accumulation of Naturally Occurring Radioactive Material or "NORM" can occur during hydrocarbon production. During the extraction of hydrocarbons and associated formation fluids, some radioactive materials may become entrained and precipitate out of suspension in the form of sulfate and carbonate scale, sands and sludge. NORM has also been known to occur where there is a commingling of reservoir fluids and where there is a significant temperature or pressure decrease (i.e. as fluids flow from the production tree towards a production facility). For example, the injection of sea water has been known to assist in the formation of NORM as it can introduce sulphates to the reservoir which start to precipitate due to the reservoir containing soluble barium and trace concentrations of Ra-226 and Ra-228.
NORM in the offshore petroleum industry is typically identified as Radium (usually Radium-226 and Radium-228) and Thorium (usually Thorium-228). These isotopes are purely radioactive and have no nuclear application. NORM activity levels have been observed to range from:
