Studies into the various decommissioning options began as far back as 1993. These studies were used to plan and engineer the detailed technical solutions and assess the environmental impacts of the decommissioning options.
The selection of the best decommissioning option for the Maureen facilities was based on thorough evaluations of all the options, with particular consideration given to ensuring that the selection process balanced technical feasibility, safety, environmental impacts, costs and impacts on other users of the sea, in accordance with national and international regulations.
Refloating the platform and the ALC in one piece for reuse at another location was the design intent. Once the technical studies confirmed the feasibility of this method, it became the chosen method for decommissioning both structures.
In June 1999, production at the Maureen field became unviable following a rapid decline in production levels. A Cessation of Production (COP) Notice was granted by the DTI on 7 October 1999.
In August of that year the Maureen owners announced that they had awarded the contract to refloat and tow the platform and ALC to Aker Offshore Partner A/S (now AkerKvaerner).
Meanwhile, the meticulous process began to obtain some 93 consents and approvals for all stages of the work to be carried out offshore and onshore. The key document for approval was the Decommissioning Programme which describes all the decommissioning works to be carried out. This was approved in December 2000 by Secretary of State for the Department of Trade & Industry.
The first phase of the decommissioning process was to prepare the structures for removal, including plugging and abandoning the 23 Maureen wells and removing hydrocarbons from the topsides and cleaning them. The three tanks were flushed with water, which was then discharged into a tanker and taken to Norway for treatment and disposal