Publications

The most optimum way to combat production decline is to open all possible reservoirs from existing wells. The same-layer reservoirs had been produced since long time ago as it is the easiest way, remaining the challenging across-layer zones, mostly shallower zones. However, most of existing wells do not fit for purpose in producing shallow zones, especially in well integrity point of view. Pilot test initially has been performed with full mitigation to produce the well without jeopardizing well integrity. However, the initial trial was too complex. This study develops fit-for-purpose mitigation in order to enable operation scalability and improve economic viability in order to perform large volume of operation and normal scope of budget. This study maintains key precautions while eliminating excessive mitigations. Key precautions to be maintained are good isolation assurance and routine well integrity monitoring. Lean mitigation applied consists of using fit-for-purpose well intervention vessel while maintaining readiness of heavy intervention barge with pressure bleed off and well killing capability. Annulus pressure anomaly will be investigated in the occurrence instead of implementing mitigations such as noise log and bleed off line installation as default operations. This lean procedure has been implemented in 4 wells. These wells could flow up to 2.6 million standard cubic feet per day (MMscfd) with total contribution at 0.4 billion standard cubic feet (BCF) and still continue flowing. No integrity issue observed after this new procedure implementation. This study showed that in order to open the possibility to produce shallow reservoirs, the method has to be validated first. Optimization only possible to be performed only if the trial has been successfully performed. On the other hand, the simple method is not possible to be performed in the first place since it will impose high risk and high uncertainty situation.