This paper describes the objectives, the completion, and the first res
ults of the dual-horizontal Well BK-4-M, which was drilled in May 1996
in the Bongkot field. The main objective of Well BK-4-M was to maximi
ze the recovery from a shallow and thin oil rim by delaying the water
breakthrough by 2 years and by maintaining a flow rate of 4,000 B/D. C
ompared with a conventional deviated well, the final recovery will inc
rease by three times. The completion of Well BK-4-M was a challenge in
terms of technical and economic planning. Well BK-4-M was put on stre
am successfully in July 1996 with a potential now rate of 4,000 B/D. T
he duration of operations was 21 days, including completion. Each of t
he two horizontal branches has a length of approximately 1000 m and is
located in the upper third of the 10-m-thick oil rim. The cost of Wel
l BK-4-M was 1.70 times higher than a conventional single-drain deviat
ed well, and the well is expected to triple recovery by using only one
platform slot. It is the first dual-horizontal well ever completed in
Southeast Asia.