A Successful Story: Improving Success Ratio Up To 80% of Well Reactivation Job Pamusian Field Case Study, Tarakan, North Kalimantan, Indonesia
Authors: Kurniawan I. 
Published: March 2023

Pamusian Field is located in northern part of North Kalimantan, Zona 10, Pertamina Hulu Indonesia area, approximately 1 km Southeast from Center of Tarakan City. Pamusian field is one of Top Ten Fields (Kalimantan Area under Pertamina EP operation Area) based on its OOIP, 553 MMSTB approximately with more than 1200 wells drilled since 1905 (brown field). However, this role doesn’t mean Pamusian production stands at tremendous number of productions. Moreover, only 50 active wells contribute to Pamusian oil production. More than 1000 wells are idles even though there bunch of oil opportunities on the idle wells. As an overall, Pamusian oil production remained constant for around 500 BOPD at 3 years back before massive reactivation delivered in 2021 & impacting to production gain achieve 150-200 BOPD gain in 2021. In the end of 2020, aligned with company’s goal to maximize existing Asset, the idea of production optimization was commissioned by improving success ratio of well reactivation job in Pamusian Field. In the last 3 years, success ratio of well reactivation job was not encouraging. The team focused on all aspects of optimization & reactivation practices. Field review & reactivation lookback are aggressively conducted to figure out Pamusian Field problems. Lack of workover & well intervention jobs, inadequate surveillance data, and miss perception of well reactivation method are raised to be the root cause for under developed field. Another surprising fact is more than a hundred attics wells located up dip in Main Closure not active (idle) which has lower surrounding well in a good oil production performance (10-30 BOPD) BOPD with various of water cut 90%. Again, this is real opportunity! Low hanging fruit to become more oil by producing those wells. An integrated and comprehensive assessment successfully delivered. Subsurface assessment cover the geological and reservoir engineering assessment. The most important outcome of this assessment is reactivation method recommendation, it’s called Locomotive (Low Cost, Massive Impact, & Innovative). Three innovations created and delivered to conduct well reactivation jobs in Pamusian field, there are Subsurface Data Hierarchy Development (to set subsurface confident level), Fill up Annulus Activity (to check fluid sample), and Locomotive Risk Mapping Assessment (to set priority by comparing confident & impact level) as decision tool. These reactivation methods delivered in high confidence level of success. Resulting a dramatic rise of success ratio up to 80% (previously 30% at 3 years back) and oil gain average 150 – 200 BOPD which remained stable for several months until early 2022. Another campaign of well reactivation programs was carried out after right to other wells and fields. Another typical reactivation was implemented, which had impressive results. All the objectives define were achieved. The outcome of the reactivation program was completely successful and exceeded the expectations which will be beneficial for value of information in capturing optimizing and development opportunities. This reactivation campaign in 2021 successfully added real oil gain & arrest production decline in Pamusian Field.