A major operator asked us to develop a decommissioning strategy for the out of service pipelines of an onshore network in an environmentally sensitive area of the UK, featuring sites of special scientific interest, special protection areas, and national nature reserves.
Due to the sensitive location and the age of the asset, a highly tailored decommissioning strategy was required to minimise risk to the environment.
Our expert team collated all available information to produce a complete inventory, before reviewing key stakeholders’ requirements and the extensive regulatory considerations. We completed a hazard identification assessment, and considered the differing options of leaving the lines in-situ or complete removal along with more specific activities such as grout-filling, sectionalising by cutting and plugging exposed ends.
A comparative assessment was completed to consider the safety and environmental issues, technical challenges and the economic cost of the various options. Key considerations included the future integrity if left in-situ, the potential to act as a channel between different environment-types such as freshwater and saltwater, and the possible effects on the irrigation systems in place.
Finally, the condition of each pipeline was assessed, the preferred pipeline cleaning options identified, and a
schedule for the decommissioning activities was produced.
We successfully identified the optimal decommissioning methodology for each of the pipelines to minimise the disturbance to the environment and the risk to people, and using technically feasible methods. It was demonstrated that the preferred decommissioning methodology for most of the pipelines would be to leave in-situ given the impact of removal on the surrounding environment.
Download our capability statement here.