Radiological risk assessment to marine biota from exposure to NORM from a decommissioned offshore oil and gas pipeline

MacIntosh, Amy; Koppel, Darren J.; Johansen, Mathew P.; Beresford, Nicholas A.; Copplestone, David; Penrose, Beth; Cresswell, Tom. 2022 Radiological risk assessment to marine biota from exposure to NORM from a decommissioned offshore oil and gas pipeline. Journal of Environmental Radioactivity, 251-252, 106979. 14, pp. https://doi.org/10.1016/j.jenvrad.2022.106979

Before downloading, please read NORA policies.

Preview

Text
N533047JA.pdf - Published Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.
Download (3MB) | Preview

Official URL: http://dx.doi.org/10.1016/j.jenvrad.2022.106979

Abstract/Summary

Scale residues can accumulate on the interior surfaces of subsea petroleum pipes and may incorporate naturally occurring radioactive materials (NORM). The persistent nature of ‘NORM scale’ may result in a radiological dose to the organisms living on or near intact pipelines. Following a scenario of in-situ decommissioning of a subsea pipeline, marine organisms occupying the exteriors or interiors of petroleum structures may have close contact with the scale or other NORM-associated contaminated substances and suffer subsequent radiological effects. This case study used radiological dose modelling software, including the ERICA Tool (v2.0), MicroShield® Pro and mathematical equations, to estimate the likely radiological doses and risks of effects from NORM-contaminated scale to marine biota from a decommissioned offshore oil and gas pipeline. Using activity concentrations of NORM (226Ra, 210Po, 210Pb, 228Ra, 228Th) from a subsea pipeline from Australia, environmental realistic exposure scenarios including radiological exposures from both an intact pipe (external only; accounting for radiation shielding by a cylindrical carbon steel pipe) and a decommissioned pipeline with corrosive breakthrough (resulting in both internal and external radiological exposure) were simulated to estimate doses to model marine organisms. Predicted dose rates for both the external only exposure (ranging from 26 μGy/h to 33 μGy/h) and a corroded pipeline (ranging from 300 μGy/h to 16,000 μGy/h) exceeded screening levels for radiological doses to environmental receptors. The study highlighted the importance of using scale-specific solubility data (i.e., Kd) values for individual NORM radionuclides for ERICA assessments. This study provides an approach for conducting marine organism dose assessments for NORM-contaminated subsea pipelines and highlights scientific gaps required to undertake risk assessments necessary to inform infrastructure decommissioning planning.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1016/j.jenvrad.2022.106979
UKCEH and CEH Sections/Science Areas:	Pollution (Science Area 2017-)
ISSN:	0265-931X
Additional Information. Not used in RCUK Gateway to Research.:	Open Access paper - full text available via Official URL link.
Additional Keywords:	decommissioning, in-situ disposal, natural radionuclides, dose modelling, contaminant, radioecology
NORA Subject Terms:	Ecology and Environment
Date made live:	12 Aug 2022 14:16 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/533047

Item Type:

Publication - Article

Digital Object Identifier (DOI):

https://doi.org/10.1016/j.jenvrad.2022.106979

UKCEH and CEH Sections/Science Areas:

Pollution (Science Area 2017-)

ISSN:

0265-931X

Additional Information. Not used in RCUK Gateway to Research.:

Open Access paper - full text available via Official URL link.

Additional Keywords:

decommissioning, in-situ disposal, natural radionuclides, dose modelling, contaminant, radioecology