Steam assisted gravity drainage(SAGD),a tertiary recovery method,has been consistently improved by experimenting various solutions in both oil-sands and heavy-oil fields in Canada.SAGD process which is consisting of two stack-up horizontal wells has been proven technology in heavy-oil fields.Employing the same concept of the gravity drainage,the 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 which require unique drilling practices.Located in Lloydminster,province of Saskatchewan in Canada,as an active Husky Energy Inc.thermal field,the Celtic pool includes 21 SAGD well pairs.In this heavy-oil pool,one of the SAGD well pair(I3/I4)was experienced production downtime shortly after it was in service.Following several unsuccessful service jobs,a few re-entry options were suggested to recover remaining reserves.These were sidetracking the I3 well,re-drilling a new well from the same pad location,or commencing a new well from different surface location.In 2010 and based on drilling risk assessment,these cases were ranked and the new horizontal producer well(I3A)was drilled close to the existing well pair.The I3A well was counter-currently placed below the existing injector well(I4)and set successfully parallel to abandoned Well I3.In Q1 of 2011 steam conditioning was completed and the new SAGD well pair(I3A/I4)has been successfully on production.Introducing the new well pair positioning,an opposite direction of SAGD well pair placement,this paper presents the original I3/I4 pair performance,its 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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