Abstract
Radioactive sources utilized in many industries, including the petroleum industry, have raised security, safety and environmental concerns. Oilfield sources are highly mobile, transported across the world and often used in remote locations. Despite safeguards and regulations, such sources have been lost, stuck down-hole, or breached. Concerns have been raised on sources being used in a radiological dispersal device (RDD). The US National Academy of Sciences, being concerned primarily with RDD, recently recommended replacing radioactive sources used in several industries with alternative sources. These include replacing Am-Be neutron sources used in porosity devices with either neutron generators which are switchable or with Cf-252 which would contain a lower amount of radioactivity. The lower risk Cs-137 source used in measuring density was spared at this time. However, a breached Cs-137 density source down-hole recently necessitated the setting up of a very long-term, elaborate monitoring program and thus such sources are of concern too.
This paper discusses the critical role of radioactive sources in petroleum exploration and production, protocols prescribed by regulators and the International Atomic Energy Agency for their safe use, concerns about their RDD potential, and lessons learned from a recent breached radioactive source incident in the field. The paper identifies additional procedures the oil industry needs to consider to use radioactive sources safely and securely, reviews the NAS recommendations and their potential impact on the industry, and describes alternatives to current chemical sources the industry is considering and the challenges which have arisen in making the transition.
