The FPSO Berge Helene (IMO 7360083) is a floating storage/production unit of 274,333 deadweight-ton capacity built in France in 1976 and converted to an FPSO in Singapore in 2005. The vessel, 372 meters long and 52 meters wide was flagged and registered in Singapore, classed by DNV GL. Our client, BW Offshore, agreed to the disposal of the FPSO Berge Helene for environmentally safe demolition and recycling in compliance with the Hong Kong Convention at ISO Priya Blue shipyard in India in 2021.
Following a successful 5 year contract win to deliver radiation protection and radioactive waste advice to BW Offshore’s worldwide fleet, our team at Aberdeen Radiation Protection Services conducted a series of radiological surveys for BW Offshore to establish levels of Naturally Occurring Radioactive Material (NORM) contamination on board FPSO Berge Helene during decommissioning.
Throughout the lifecycle of the Berge Helene decommissioning project, a dedicated team from ARPS, including RPAs and RPSs, provided vital support and advice to the client to help them achieve their project goal – to clean the FPSO as far as was reasonably practicable to background levels of NORM.
Challenges
One of the major challenges faced in-field whilst executing the disconnection and demobilisation (D&D) scope is often the removal of NORM decontamination from the FPSO’s process and cargo systems.
The scope and extent of the NORM decontamination carried out was vast.
NORM can surface naturally or through human activities such as mining, and oil and gas extraction. NORM is radioactive. Once it is brought to the surface or concentrated, the ionizing radiation that it emits can affect humans resulting in various cancers.
Ensuring that the decontamination scope was detailed and sufficient for decontamination contractors to be effective on the project was essential to protecting people during the decommissioning process.
The Solution
After the cessation of production in December 2017, ARPS had an almost continuous presence onboard Berge Helene from Q1 of 2018 to provide advice on, and verification of the NORM cleaning activities – which encompassed pipework, tanks, vessels, and other associated equipment – carried out by the onboard cleaning crew. ARPS personnel used T407 contamination monitors and probes to identify areas where further cleaning was required until there were no readings of NORM above background levels.
In Q2 2018, the Berge Helene FPSO left Mauritanian Waters after the successful disconnection and demobilisation of the facility. ARPS personnel met all KPIs (Key Performance Indicators) in the delivery of this project and the team was proud to play a key role in such an overwhelming decommissioning success story.
The radiation compliance audits carried out by ARPS at onshore and offshore sites provide a detailed assessment of the performance of the sites in terms of legislative and regulatory compliance, conformance with company procedures and best practices. Members of the ARPS team take a proactive approach during these audits and the opportunity is often taken to provide one-to-one coaching for site RPSs.
