THE MONITORING AND TREATMENT OF THE DRILL CUTTINGS ACCUMULATION DURING OPERATION AND DECOMMISSIONING - MAUREEN ALPHA, BLOCK 16/29A UKCS

摘要

As a first phase in its decommissioning the Maureen Alpha Steel Gravity Base platform was refloated from Block 16/29A on the United Kingdom Continental Shelf to Norway in late June 2001. In order to carry out this decommissioning the Maureen Owners, through the Operator, Phillips Petroleum Company United Kingdom Limited, had to obtain approval from the UK Govemment of a Decommissioning Programme to be executed in accordance with the UK Petroleum Act 1998 and its Decommissioning Guidelines. In compiling the Decommissioning Programme the Maureen Operator needed to consider inter alia the environmental aspects of all its operations. Into this analysis came the issue of the Drill Cuttings accumulation which lay beneath and beyond the platform. This paper will describe the factors and methodology used to develop the position taken with respect to treatment of the historic drill cuttings accumulation arising from drilling 26 wells. At the time of the preparation of the Decommissioning Programme (early 2000) until the refloat of the platform, the Environmental Non Governmental Organisations were keenly interested in the fate of drill cuttings and the Oil Industry in the UK was carrying out a project to determine the impact and management issues around such accumulations. The seabed around Maureen had been sampled extensively before drilling and throughout field life. This was significant within the development at the Decommissioning Programme. The paper will include discussion of Drilling History, long term monitoring, recovery of species diversity, links to industry study work, peer and academic review, disturbance modelling, environmental modelling and the actual disturbance of the cuttings at the time of refloat.