The current low oil price has resulted in several continuous improvement drives particularly focused on capital efficiency. With over 60 producing oil fields and approximately 700 producing wells, some of which date back to the 60s, work over operations in Shell Petroleum Development Company (SPDC) is imperative. Having completed over twenty (20) Work Over operations in the last six years in SPDC, the importance of Work Over operations as a means to sustain production especially for relatively old, dysfunctional or non-compliant wells and keep the production funnel full at a relatively lower cost compared to new drills is more evident. Work over operations, defined as the repair and/or stimulation of existing wells in order to improve production performance presents the opportunity to maximize short term gains from already existing facilities. The objective of the workover operations on Agbada ABC and XYZ was to restore well integrity with the installation of sub surface safety valves and gas lift mandrels instead of insert orifice while assuring the development of oil and associated gas. The insert orifice had been installed on both wells to enable gas lift operations from the Agbada Associated Gas Gathering (AGG) plant since they were unable to sustain natural flow. However, due to epileptic AGG, both wells quit frequently requiring nitrogen lift with an average Non-Productive Times (NPT) of 6 months per year while Agbada XYZ was put on cyclic production and had been a pressure build-up well with at least two weeks down time per month. The workover operation was therefore proposed to replace the existing (punched) tubing, install proper gas lift mandrels for optimum performance, reduce well operating cost arising from AGG outage and/or compressor failure and restore production in the reservoir. This paper aims to discuss the cost reduction strategies such as collaboration, re-use, program optimization and operational efficiency applied in driving down Non-Productive Times (NPT) in the efficient delivery of these workover operations which resulted in <6% NPT, >30% time savings, ca. 40% cost savings and early return of wells to production.

The exploration and production of oil and gas mostly occurs in remote locations, so as to minimize human exposure and Health Security Safety and Environment (HSSE) risks. Shell Companies in Nigeria is not any different having operated for over 50 years in Nigeria with the largest footprint of all the international oil and gas companies operating in the country spanning over land, swamp, shallow waters and offshore terrains. Shell Petroleum Development Company, the operator of a joint venture (the SPDC JV) between the government-owned Nigerian National Petroleum Corporation – NNPC (55% share), Shell (30%), Total E&P Nigeria Ltd (10%) and the ENI subsidiary Agip Oil Company Limited (5%) focuses mostly on onshore and shallow water oil and gas production in the Niger Delta with about 60+ producing oil and gas fields and a network of approximately 5,000 kilometers of oil and gas pipelines and flow lines spread across the Niger Delta. Escravos Beach is over 60km from the closest major city, Warri, a major oil and gas zone in the Niger Delta. It is bounded by the Escravos River to the East, Chevron canal to the North and the Atlantic Ocean to the South and is covered with predominantly mangrove forest especially along the creeks and consists of a number of natural and man-made waterways (rivers, creeks and canals). Unlike most other onshore operations, this location can only be accessed via the waterways; thus requiring the rig equipment and every other equipment to be channeled via the waterways and subsequently on land to arrive at the site. The amphibious nature of this operation requires a combination of onshore and swamp requirements with increased HSSE exposure, logistics requirement and cost. This paper aims to highlight the practical experience garnered in the rig move and workover operations of Rig XYZ which operated in the Escravos Beach region.