The objective of this paper is to describe the well management process which includes the design methodology and the well execution procedures utilized by Petrobras International to drill its first ultra deepwater well in a remote and challenging area of the Turkish waters in the Black Sea. Ranked as a well of the highest complexity level, the drilling of this wildcat deepwater well has faced a number of expected hazards such as the presence of shallow gas zones, long abnormally pressurized intervals, low fracture pressure gradient sections, loss circulation zones due to the presence of fractured limestone, great potential for false kicks (breathing formation and ballooning) and the possibility of having gas migration to the riser. In addition to the risks listed above, the well location, in the middle of a remote area of the Black Sea, has been also considered a great challenge in terms of operational logistics. This came from the fact that Petrobras had to plan all its operations from scratch, including moving a huge semi-submersible drilling rig under the bridges located on the Bosphorus Strait. In this work it is also presented the Well Classification Methodology developed by Petrobras. Such method takes into account several factors that includes water depth, number of well drilled in the area, the existence of abnormally pressurized formations and a number of other obstacles. The main idea of this procedure is to establish the proper well design robustness and to define operations actions which should be used to mitigate operational problems that could arise. Despite of all these challenges, the well was executed according to its original plan indicating that the methodology was successfully applied and can be repeated in other wells. A number of lessons learned during the planning and execution phases of this project are also discussed within the scope of this work.
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