Sangomar

Sangomar Oil Field Project Profile

Location

The Sangomar oil field, formerly known as the SNE field, is located approximately 100 kilometers south of Dakar, the capital city of Senegal. It is situated within the Rufisque, Sangomar, and Sangomar Deep Blocks, covering an area of 7,490 square kilometers in the Senegalese portion of the Mauritania-Senegal-Guinea Bissau Basin. The water depth in the region ranges from 700 to 1,400 meters.

Discovery and Appraisal

The Sangomar oil field was discovered in November 2014 with the drilling of the SNE-1 exploration well, which encountered a 95-meter gross oil-bearing column within upper Albian sandstones at a water depth of approximately 1,100 meters and a total depth of 3,000 meters. Further appraisal wells, including SNE-2, SNE-3, SNE-4, and BEL-1, were drilled from November 2015 to May 2016 to evaluate the field's potential.

Project Development

The project is being developed by a joint venture comprising Rufisque Offshore, Sangomar Offshore, and Sangomar Deep Offshore (RSSD), with Woodside Energy as the operator holding an 82% interest and Societé des Petroles du Sénégal (Petrosen) holding an 18% interest in the Sangomar exploitation area. In the remaining RSSD evaluation area, Woodside holds a 90% stake and Petrosen holds 10%.

• Phase 1 Development: The initial phase focuses on developing the less complex reservoir areas and testing nearby reservoirs. This phase includes the development of 23 wells (11 production, 10 water injection, and 2 gas injection), with 21 wells already drilled and completed as of June 2024. A 24th production well has been approved and will be completed in the current campaign.

Infrastructure

• FPSO: The project features a permanently moored floating production storage and offloading (FPSO) facility named Leopold Sedar Senghor. This FPSO is a converted large crude carrier oil tanker, moored at a water depth of approximately 780 meters using SOFEC’s external turret mooring system. The FPSO is capable of processing 100,000 barrels of crude oil per day, 130 million standard cubic feet of gas per day, and 145,000 barrels of water injection per day. It has a storage capacity of 1.3 million barrels of crude oil.

• Subsea Systems: The subsea system includes wellheads and subsea trees, in-line tees, manifolds, flowlines, and risers connecting to the FPSO, as well as umbilicals for monitoring the wells. The subsea infrastructure is designed to support subsequent development phases, including gas export to shore and potential future subsea tie-backs from other reservoirs and fields.

Contractors and Suppliers

• MODEC: Awarded the Front End Engineering Design (FEED) contract for the FPSO in February 2019 and the FPSO purchase contract following the Final Investment Decision (FID) in January 2020. MODEC operates the FPSO under a 10-year operation and maintenance contract with 10 one-year extension options.
• COSCO Shipping Heavy Industry (Dalian): Responsible for the hull and marine works, external turret, and topsides module installation and conversion work on the vessel.
• BOMESC Offshore Engineering Company: Involved in fabricating the topsides modules of the FPSO.
• Penglai Jutal Offshore Engineering Heavy Industries (PJOE): Built the external turret mooring system.

Production and Revenue

• First Oil: Achieved in June 2024, marking Senegal’s first offshore oil production.
• Production Capacity: The FPSO can process 100,000 barrels of crude oil per day. The crude quality is expected to be 31 degrees API, which is in demand in European and Asian markets.
• Revenue: The first phase of the development is expected to generate $2 billion to $4 billion of direct revenue for the Government of Senegal.

Environmental and Social Impact

• Assessments and Approvals: The environmental and social impact assessment for phase one was completed in November 2018. The development and exploitation plan was submitted to the Senegalese government in October 2018, and front-end engineering and design activities began in December 2018 following government approvals.

Project Timeline

• Discovery: November 2014
• Appraisal Wells: November 2015 to May 2016
• Final Investment Decision: January 2020
• Construction and Development: Began in early 2020
• Completion of FPSO Construction: Announced in November 2022
• First Oil: Achieved in June 2024.

Project Costs

The total cost of the project is estimated to range between $4.9 billion and $5.2 billion.

Future Development

The project is designed to allow for the integration of subsequent development phases, including gas export to shore and potential future subsea tie-backs from other reservoirs and fields. The total recoverable oil resources are estimated to be around 500 million barrels over the life of the field.