Summit Award Winners
THE APEGGA Project Achievement Award
Well Network Drilling Project
The project was initiated by the Wabasca
Resource Development Team of Amoco Canada Petroleum Company Limited in
response to challenges presented by development of the Wabasca-Pelican
Lake heavy oil play north of Slave Lake.
In 1995, commercial, horizontal drilling
for Amoco in Wabasca consisted of a 1,200-metre-long, lined horizontal
wellbore. These single wells with slotted liners became known as a single
well equivalent (SWE). In order to reduce development costs, the team
eliminated the slotted liner and drilled an experimental openhole horizontal
well. Success of this unlined wellbore field trial resulted in three more
unlined tests, and led to a simplified multilateral technique with wells
consisting of up to five legs, only one of which was lined. This process
reduced the drill, complete and equip (D, C & E) costs to 60 per cent
of a SWE.
As above-average rainfall made road construction
on the muskeg increasingly difficult, the team identified the need to
get out of the road-building business to make the play a success. This
required drilling horizontal wells much longer than conventional techniques
allow, since longer wells could develop more land with fewer roads. The
team attacked the problem in two ways. The first technique, through innovations
in drill string design, using a top drive and special drilling fluid additives
allowed one extended reach well to achieve a world record horizontal displacement
to true vertical depth ratio of 7.20. The horizontal leg on this well
stretched to over 2,700 metres, an increase of over 225 per cent from
a standard 1,200-metre well.
The second, patent-pending technique was
to drill horizontal wellbores to establish effective fluid communication
with a main production well. This technique was attempted on two existing
horizontal wells, one of which succeeded. This led to planning and drilling
of a large drainage network specifically designed to use this technology.
A main conduit drainhole — with production equipment and facilities for
the network was drilled from a permanent all-weather surface location.
Two wells were drilled to communicate with this conduit well. These communicating
wells were drilled from frozen, winter-access-only sites. All three wellbores
were then effectively produced from the first permanent conduit location.
When fully developed, this network will develop five sections of land
from one permanent surface location versus half a section for comparable
conventional horizontal methods.
As well as achieving costs of 50-60 per
cent of that of conventional wells, a number of operational benefits were
realized, including level loading of surface equipment, improved serviceability
and more effective use of operations manpower. A major win was also achieved
on the environmental side by reducing permanent surface access and flowline
requirements. By gathering more production to a single point, the feasibility
of waste methane recovery to reduce greenhouse gas loading was enhanced.
These efforts helped Amoco to achieve peak production rates in excess
of 14,000 barrels of oil per day at Wabasca.
Nearly 80 per cent of major services were
provided by Alberta-based companies, including Precision Drilling, Tesco
Corp, Bigstone Band Enterprises, McLeay Geological Consultants, Prudential
Steel and GL Slotco. Morley Frank, P.Eng., of Bear River Engineering provided
drilling engineering and project management.
This model of extended reach wells was
quickly adopted by other operators in the area, and is being used successfully
The technique also may open the door to
a new, enhanced oil recovery methods in Alberta’s oil sands.