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Abstract This paper will describe the project organization, methods, philosophy and execution used to develop the Ceiba Field; a fast track, two phased, subsea tieback to an FPSO, offshore Equatorial Guinea. It will detail the advance planning that was done by Triton Equatorial Guinea, Inc. (acquired by Amerada Hess in August 2000), the engineering study performed for Ceiba, the process by which primary contractors were selected and how the coordination of various aspects were handled. The paper will discuss the installation of the early production system and startup of the field in less than 14 months from discovery and subsequent expansion of the system in the following 14 months. Introduction Triton discovered the Ceiba Field in October 1999 in the previously under-explored Rio Muni Basin in the Gulf of Guinea, offshore Equatorial Guinea. Following the discovery well, Ceiba-1, and drilling of the confirmation well, Ceiba-2, Triton embarked on an aggressive development with prudent risk management to achieve first oil production in a record setting 14 months from discovery. (Figure 1) The Ceiba Field development was implemented in two phases. Phase 1 is an early production system whereby four subsea trees and manifolds are tied back to a spread moored FPSO in shallow water. Water depth at the FPSO location is 90 meters and approximately 700 meters at the subsea wells. Each Phase 1 well is tied back to the FPSO via dual 8" insulated steel flowlines with flexible jumper connections to the manifolds. Flexible risers from each flowline are supported by a riser support structure (RSS) set on the seabed adjacent to the FPSO. Separate multifunction control umbilicals are routed along the flowline routes to the individual manifolds withintegral subsea distribution units (SDU). Phase 1A was implemented in parallel with Phase 1. While Phase 1 equipment was being fabricated and installed, Phase 1A engineering, design and start of manufacture was in process. Phase 1A added two, four well production manifold systems; three, four well water injection manifold systems; and one satellite water injection well. Production manifolds are tied back to the FPSO with dual 10" flowlines. Water injection manifolds are tied back with single 10" flowlines. Additional processing capacity on the FPSO for production and water injection was accomplished by changing out the FPSO rather than adding process modules in the field. Phase 1A start up occurred 14 months after the Phase 1 first oil milestone. Ceiba Development Early Planning and Conceptual Engineering By the end of the first quarter of 1999, Triton had assembled a multi-disciplinary team of exploration and operations personnel to develop a plan for drilling and appraisal of Triton's license acreage in Blocks F and G. Concurrent with the exploration team work, early in-house conceptual engineering work was done with cost estimating software and information in the public domain. This work helped to evaluate possible development concepts and was incorporated into project economics.

This paper emphasizes the concept of "as-built" reliability vs "as-designed" reliability related to fixed offshore platforms. After an offshore platform is initially designed in accordance with criteria based on probabilistic concepts, modifications may be introduced which can affect its intended structural reliability. These modifications can occur during the various phases of design, fabrication, and installation. Several examples of such changes are cited. A brief outline of one approach to computing a platform's probability of failure is also presented and a computational example is included to illlustrate the methodology of comparing the as-built reliability with the as-designed reliability.