Well Integrity Management in Talisman Energy Norway: A Systematic Way of Describing and Keeping Track of the Integrity Status for Wells in Operation

Abstract
Talisman operates several fields on the Norwegian Continental Shelf (NCS), many of these mature fields are taken over at the end of their design life. These old fields represent challenges with respect to well integrity and overall profitability.

Talisman is a member of the Well Integrity Forum (WIF), a co-operative effort between the operating companies on the NCS to define a unified approach for handling well integrity. Using WIMS and the WIF recommendations together with internal guidelines improves Talismans ability to handle well integrity issues throughout the production phase of a well and in compliance with regulatory requirements.

This paper describes how Talisman Energy Norway (Talisman) manages well integrity for their assets, and discusses the benefits, challenges and lessons learned from implementing a well integrity management system, focusing on technical and organizational aspects.

Introduction
In 2006 the Norwegian petroleum authority (PSA) initiated a comprehensive well integrity survey of seven operating companies on the Norwegian Continental Shelf (NCS) and pre-selected offshore facilities/wells. The survey indicated that in average 18 % of the production- and injection wells were to some degree impaired by well integrity issues (PSA, 2006). The PSA concluded that each of the participating companies generally needed to improve their focus on well integrity issues, and stated; "It is recommended that the operating companies review their in-house management systems for compliance with the requirements in the regulations for barriers and how this is distributed and actively used internally to reduce the chances for any incidents??. The PSA study and similar studies with focus on well integrity (e.g., Bourgoyne et al 2000) have increased the emphasis on well integrity among the operating companies on the NCS.

Standards like NORSOK D-010 and API RP90 have also increased the focus on well integrity. NORSOK D-010 defines well integrity as "the application of technical, operational, and organizational solutions to reduce risk of uncontrolled release of formation fluids throughout the life cycle of the well.?? This definition is widely accepted on the NCS. The focus on well integrity is not only reflected in authority audits and standard. Most NCS operating companies have also included/revised well integrity requirements in their organisation and steering documents in the recent years.

Today the operating companies are followed-up internally by management and by the PSA on their ability to maintain and manage well integrity. It can therefore be argued that companies with control of their well integrity have a competitive advantage. As such, well integrity has become part of the oil companies' business strategy.
This paper describes how Talisman Energy Norway (Talisman) manages well integrity for their assets, and discusses the benefits, challenges and lessons learned from implementing a well integrity management system, focusing on technical and organizational aspects.

Talisman operates several fields on the NCS, many of these mature fields taken over at the end of their design life. These fields represent challenges with respect to well integrity and overall profitability.

Talisman has in the recent years focused on improving its ability to manage well integrity. Early 2008, Talisman purchased a well integrity management system (WIMS) and have since customized the tool to their requirements. WIMS is a tool that enables and facilitates changes to how Talisman works and manages well integrity. Currently the tool is implemented on Gyda and Varg A.

Talisman is also a member of the Well Integrity Forum (WIF), a co-operative effort between the operating companies on the NCS to define a unified approach for handling well integrity based on prevailing regulations and standards.