BP's Wolf Lake Project involves the construction and operation of facilities for the production of bitumen from BP's Marguerite Lake leases. The leases cover an area of 30,000 hectares located about 50 kilometres north of Bonnyville in northeastern Alberta, Canada. The initial facilities include 192 wellss directionally drilled from pads of 16 to 21 wells per pad. These wells were drilled between October 1983 and July 1984. This paper discusses the drilling program at Wo1f Lake; it includes well design, equipment design, directional program, drilling data base, a record of performance, and a review of innovative and optimization techniques employed.
BP has been investigating heavy oil recovery using the cyclic steam and in-situ combustion processes since 1964. Results of this initial work were sufficiently encouraging for BP, in conjunction with Petro-Canada, to commence construction of the Wolf Lake Project which will produce 1,100 m3 per day (7,000 BID) of bitumen. The project occupies a part of BP's Marguerite lake leases, which cover an area of 30,000 hectares (75,000 acres) some 50 kilometres (30 miles) north of Bonnyville, in northeastern Alberta (Figure 1).
At the start of production, 192 wells will be operating. As the average production rate from each well declines, new well s will be added to maintain 1,100 m3/d production. Typically, an average of 350 wells will be in operation at any one time. It is estimated that a total of 800 wells will be drilled during the 25-year life of the project.
To minimize environmental disturbance and cost, the wells are positioned in cluster sites (or pads) with 16 to 21 well 5 directionally drilled from each pad. The drilling of the first 192 wells in 1983–84 are the subject of this paper.
The Wolf Lake Project drilling program consisted of ten pads, containing 192 wells. Drilling was scheduled to commence in October 1983 with completion by mid-February, 1985. The wells were scheduled to take four days each, and two drilling rigs were contracted for this work. This two rig program, rather than a multi-rig program, was selected to limit the time lost while progressing through the expected learning curve. The 1 1/2 year program was planned to allow time for the implementation of drilling optimization programs, and for the payout of specialized rig equipment. This schedule also met the Oil Sands Plant construction timetable.
Figure 2 is a plan view of a typical pad, showing surface location and target area in which the reservoir was to be penetrated. Targets were rectangular in shape, 5 m by 10 m. Surface locations were 5 m apart and arranged in a "c" configuration. The surface area of the pad was approximately 110 m × 70 m.
Maximum horizontal displacement from well head to bottomhole target was designed to be about 250 m, and the maximum inclination from vertical about 45 °.
A typical well design is shown in Figure 3. Firstly, 20 m of 305 nm conductor pipe was pre-set with a rat hole rig.