Steam assisted gravity drainage (SAGD), a tertiary recovery method, has been consistently improved by experimenting with various solutions in both oil-sands and heavyoil fields in Canada. The SAGD process consists of two stacked horizontal wells and is proven technology in heavy-oil fields. Employing the same concept of gravity drainage, SAGD well placement convention has been revisited and challenged many times. Known to the industry, the X-SAGD and JAGD processes are two examples of fit-for-purpose well design and recovery schemes that require unique drilling practices. The Celtic pool, located in Lloydminster, Saskatchewan in Canada is an active Husky Energy Inc. thermal field that includes 21 SAGD well pairs. In this heavy-oil pool, one of the SAGD well pairs (I3/I4) experienced production downtime shortly after coming into service. Following numerous unsuccessful service jobs, several re-entry options were suggested to recover remaining reserves. These included sidetracking the I3 well, re-drilling a new well from the same pad location, or commencing a new well from a different surface location. These cases were ranked and in 2010, based on a drilling risk assessment, the new horizontal producer well (I3A) was drilled close to the existing well pair. The I3A well was placed counter-currently below the exisiting injector well (I4) and successfully set parallel to the abandoned Well I3. Steam conditioning was completed in the first quarter of 2011, and the new SAGD well pair (I3A/I4) has been successfully put on production.

The new well pair was positioned in the opposite direction of a conventional SAGD well pair placement. This paper presents the original I3/I4 pair performance, the challenges, result of re-drilling Well I3A, reservoir simulation study and recent field production of the I3A/I4 SAGD well pair.

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