Naturally occurring radioactive material (NORM) is present in oil and gas deposits. The extraction, movement, processing, and storage of oil and gas can influence the activity concentrations of radionuclides present in raw materials, products, by-products and wastes. Of these, sludges, scales, and produced water can have radioactivity concentrations substantially higher than natural background levels and may warrant risk mitigation controls to limit exposure to people and the environment. An example exposure scenario is that of workers conducting ‘pigging’ to clean pipelines of scale that contains NORM.
Radiological exposure hazards from NORMS can be managed using national and international guidance documents through consideration of the exposure source, the exposure pathway, and the receptor. The exposure source is not only typically the most difficult to control, but also the least quantified. Measuring radioactivity concentrations in the exposure source is fundamental to understanding the distribution of radioactivity and managing hazards associated with NORM in the oil and gas industry.
This presentation explains the process and challenges of radiological laboratory measurements to quantify radioactivity concentrations in NORM samples from the oil and gas industry analysed by the Queensland Health Radiation Health Unit. In particular, measuring isotopes of radium, uranium and thorium, 210Pb and 210Po in sample matrices with complex physical and chemical properties. The variability in activity concentrations of radionuclides between materials and sites are discussed with deidentified data provided from previously unreleased laboratory measurements and published literature.