Decommissioning is necessary in the life cycle end of any oilfield. Decommissioning issues are of particular importance for offshore fields, which pose the greatest risks to the preservation of ecological systems. Subsea pipeline infrastructure occupies a significant place in the total works of the offshore field decommissioning. In practice, a variety of the abandonment methods of the submarine pipelines can be used, from leaving in-situ to removing the pipeline completely, with the reconstruction of the previous submarine relief. Subsea pipelines decommissioning is a carefully planned in advance sequence of activities, which are the safest and most economically feasible. Submarine pipelines decommissioning is reviewed on the individually basis, using comparative analysis, whereby a decision is made on the appropriate decommissioning method. The article considers Vietsovpetro JV existing technical solutions and the milestones of the submarine pipelines decommissioning. The authors analyzed current international practices for the subsea pipelines decommissioning, in order to optimize expenses and practice application. The authors considered the pipeline mechanical cutting method by hydraulic power shear and had carried out a comparative study with the existing in Vietsovpetro JV cutting methods, based on this data the feasibility conclusions were implemented. The list of the measures proposed for Vietsovpetro JV adoption is given in order to optimize costs of the submarine pipelines decommissioning.
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