Abstract SPE – Proposal for Paper ‘North West Hutton Decommissioning - a Major Challenge.…a Major success’
Description and Scope This paper describes the HSE challenges surrounding the decommissioning and removal of the first UK Major Offshore Installation in the UK sector of the North Sea, the North West Hutton (NWH) installation. The paper will explain how excellent HSE performance was maintained throughout a complicated and many faceted project, including dealing with; the harsh North Sea environment, the interfacing of an array of contractor disciplines and a multi-national workforce. The many lessons learned during the project are outlined.
The NWH Installation comprised an 18,000 tonne steel jacket support structure and 20,000 tonnes of topsides module. In removal terms this involved the reverse installation of 21 modules, followed by subsea cutting and removal of 58 sections of steel jacket, sitting in 140m water in the northern North Sea.
If the NWH decommissioning project was going to protect the offshore workforce and the environment there had to be a clear hazard management strategy and implementation programme. It was essential that hazard management was integrated right from selection of the right removal engineering solution through to final disposal. The work was executed safely through building an excellent relationship with all contractors and provision of absolute clarity on expectations, standards and processes and their communication and application.
Application The information in this paper will be of interest and use to for the planning of any offshore decommissioning activities.
Results and Conclusions The total offshore removal programme was executed with approximately 900,000 man hours. There were no days away from work cases or high potential safety incidents. A number of lessons were learned, including:
Benefits of good early upfront planning with an integrated contractor workforce
Good communications of expectations, taking into consideration a multi-national workforce
Clarity on hazard management processes
Development and implementation of a Human Factors strategy
Good assurance of compliance
The NWH experience has shown that major decommissioning projects, including a multitude of hazardous activities can be undertaken safely and without damage to the environment.
Significance of Subject Matter This project was a pivotal North Sea milestone and a UK first for size of installation, complexity and removal environment. As such there have been valuable learnings in managing safe and successful offshore decommissioning.