The K5.4 well was located offshore Sarawak and was the fifth well drilled in the area. It had objectives of characterizing the high temperature carbonate reservoir containing 70% CO2 and acquiring core samples. Challenges included uncertainty around the reservoir and potential for losses while coring. To address these, the team conducted planning, risk assessments, and lessons learned from previous projects. Through preparation and teamwork, the well was successfully completed ahead of schedule and under budget, achieving all objectives including the longest carbonate core in PETRONAS history and first injectivity test in a high CO2 carbonate reservoir.

1. K5.4 Success Story (18th March 2015 to 27th July 2015)
Introduction
The K5.4 well is located in SK302B open block in the western
part of the Central Luconia province, offshore Sarawak. It is
the fifth well that has been drilled after K5.1 (1970), K5.2
(1997), K5.2 RDR (1997) and K5.3 (2006). It is a high
temperature carbonate reservoir (312 deg F) containing 70%
CO2 and 70ppm H2S. The well was budgeted for 75 MM USD
and planned for 139 days with two DST.
Well Objectives
The well objectives were to acquire all the critical data that
can help in reducing the uncertainties of the cap rock
integrity, CO2 injectivity & geochemical properties by
obtaining cap rock core samples, obtain carbonate core
samples for reservoir characterization & de-risking GIIP,
ascertain wax content & contaminants through fluid
sampling. The proposed TD of the well would be at 2475m
TVDSS which would explore 151m into the S1 reservoir.
Challenges
 High temperature carbonate reservoir with 70% CO2 and
70ppm H2S content in reservoir
 Uncertainty of the Top of Carbonate
 Coring in potential total losses zone in carbonate section
 Coring in transition zone with potential total losses
 Pioneer in aquifer injectivity test
 Remote location
 Poor performance of coring service provider during
carbonate coring in previous project (Kuang North-3)
 Changing DD/MWD service provider at the last moment
Initiative Summary
To deal with the above challenges, the team worked on the
following initiatives:
 Run VSP log 70m above Top of Carbonate to minimize
risk of poking carbonate & encountering total losses.
 Reorganized the coring service provider manpower, held
coring workshop, reviewed coring program in detail and
incorporated coring lessons learnt from Kuang North-3.
 Did PMCD PRA to come up with mitigation plans in case
of event of total losses while coring in carbonate
reservoir.
 Did detailed risk assessment for water zone injectivity
test and well testing in high CO2 reservoir (70%).
Implementation
K5.4 plan was successfully implemented because of the
following reasons:
 Active HSE participation from all as seen in the 100%
participation of the HUNS Card, Compliance to PCSB Stop
Work Policy, ZETO Rules and Rig As A Second Home
Campaign.
 Prepared Detailed Drilling Program and Standing
Instructions for Driller (SID).
 Pre Job Planning and Materials Take Off review with all
related service providers & logistics personnel.
 Have contingency back up plan and mitigation in place
based on identified risks for each hole section.
 Working as one team with close coordination with G&G
and Well testing team.
 Using PRTVC communication system efficiently during
daily operation morning meeting.
 Diligently monitoring the drilling operations with using
Real Time Monitoring (RTD & RTO)
 Capturing the after action reviews (AAR)/lessons learnt
from each hole section/job to be applied for next hole
section/project.
 All documents stored for easy access and recordkeeping
in ECM for everyone’s reference.
Results
 Recorded 2,071,682 man-hours with zero LTI and & TRCF
 Achieved all well objectives
 Rated as Best in Class well in DDPTF and DCPF
 8.5 days ahead of NOOP (139days)
 12 million USD lower than AFE (75 mill USD)
 Relatively low NPT 7.8%
 Longest carbonate core in PETRONAS (224m) with 98%
core recovery
 100% core recovery for cap rock shale coring
 First mini frac test in Malaysia
 First aquifer injectivity test in carbonate reservoir
containing high CO2 in PETRONAS
 Successfully flared 70% CO2 for first time in PETRONAS
 Compliance to P2P