The Ufuq field, operated by Petroleum Development Oman (PDO), is located in Oman in close proximity to the Lekhwair field, the discovery well being drilled in early 2006. An appraisal well was subsequently drilled with the objective of further evaluating the discovery and delineating its’ extent so that early commercial development decisions could be made. This second well was drilled with an extended horizontal section which identified a second zone of reservoir quality rock above the main zone of interest.

As a consequence a second horizontal section was drilled to optimize the intersection of the two reservoir units and plans were made for evaluation testing. The first part of the test was planned to evaluate commingled flow while the second was to plug off the additional zone and flow test the main zone. To achieve these objectives, a unique combination of a 92° well inclination and an open hole scab liner were used with the scab liner providing a seat for an inflatable bridge plug to be set to isolate the upper zone once commingled testing was complete. Following testing of the main or lower zone the plug was retrieved thru-tubing and the well returned to commingled flow.

In this paper the authors will review in detail the planning and execution of this procedure which avoided a workover, thereby saving 7 days of rig time, and was a "first" for both Operator and supplier.

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