Radiation impact on growth of marine algae: informing offshore oil and gas decommissioning

Alexandra Bastick, an honours student at Charles Sturt, has researched the impact of ionising radiation on marine microalgae at ANSTO’s Lucas Heights campus. Her study focused on how decommissioned pipelines containing Naturally Occurring Radioactive Materials (NORM) might affect marine organisms. Australian legislation currently mandates the complete removal of decommissioned offshore oil and gas facilities, but there has been discussion around the benefits of leaving certain infrastructure as artificial reefs to enhance local biodiversity in these ecosystems.

Using a sealed source of radioactive Cesium-137 to generate external radiation dose rates expected from NORM contaminated pipelines, she simulated ocean environments in the lab and found minimal growth impact on Tisochrysis. This is a first step in creating the possibility of suitable decommissioning options for this type of infrastructure. This work also attracted interest at the 2024 joint conference with AMSA and NZ Marine Sciences Society, where Alex was awarded the Ron Kenny Award for her work.