The 2014 Wood Review is a report reviewing UK offshore oil and gas recovery and its regulation, led by Sir Ian Wood. The report identifies and addresses key challenges in the UK petroleum industry, among them the lack of a strong regulatory body and a decommissioning strategy. The UK petroleum industry is mature, and Norway may benefit from UK's experiences in decommissioning. The article investigates the applicability of the Wood Review recommendations for decommissioning in Norway. The analysis of the recommendations in the Wood Review is carried out by a SWOT-analysis of the general recommendations with a high potential impact on decommissioning as well as the five recommendations specific to decommissioning. The recommendations in the Wood Review were broadly accepted by UK authorities and formed the basis for numerous initiatives aimed at improving policies and practices in UK decommissioning. The key initiatives are presented to illustrate how the Wood Review recommendations has been interpreted. A summary of the key differences between the petroleum industries and the regulatory authorities in Norway and the UK is provided for background. Decommissioning in Norway face similar challenges to those identified in the Wood Review. The analysis indicates that several of the UK initiatives following the recommendations in the Wood Review has the potential of improving decommissioning in Norway. Differences in regulatory regimes between the regions may complicate the implementation of some of the initiatives following the Wood Review in Norway. In most cases only minor changes to regulations and/or practices are required. Recent UK initiatives with a high impact on decommissioning include increased focus on sharing of information and lessons learned, increased collaboration, the development of a decommissioning strategy, benchmarking of decommissioning cost estimates for all projects and the development and publishing of annual UK decommissioning cost estimates. There are indications that the Norwegian Petroleum Directorate (NPD) and the Norwegian Ministry of Petroleum and Energy (MPE) are falling behind their UK counterparts in key areas. Norway has limited experience with decommissioning, and scrupulous analysis of lessons learned in other regions is essential. Decommissioning of Norwegian offshore infrastructure is a major undertaking and even minor improvements may have a substantial impact on personnel risk, risk to the environment or the total decommissioning expenditure. The Norwegian regulatory regime has been an integral part of the Norwegian petroleum industry's success in previous decades, and changes to the regime require careful deliberation. The recent implementation of initiatives aimed at improving decommissioning regulations and practices in the UK represents a unique learning opportunity for Norwegian authorities. The analysis suggest that Norway may benefit from adopting some of the UK initiatives following the Wood Review recommendations.

Quality data is essential for calculations of expected leakage in wells post Permanent Plug and Abandonment (PP&A). Such data may come from surveys studying hydrocarbon leakage to the marine environment. However, recent literature suggests that current regulatory practices for environmental surveys are suboptimal, giving reason to question the assumption that wells have experienced zero leakage from the deep reservoir post PP&A on the Norwegian Continental Shelf (NCS). We investigate whether such an assumption is credible. The credibility of the assumption of zero leakages is investigated through a review of literature addressing the integrity of wells post PP&A on the NCS, with particular emphasis on a 2021 report from the Norwegian Environmental Agency (NEA). Based on the review, the strength of knowledge supporting the assumption that no wells on the NCS have experienced leakages from their deep reservoirs is discussed. The implications of the uncertainty associated with the assumption of zero leakage on the NCS, the rationale for collecting more relevant data, and how these data may be obtained is also discussed in brief. The NEA report details the current regulatory practice for environmental surveys on the NCS. This regulatory practice, as it is described in the NEA report, give limited support to a zero leakage assumption. Norwegian regulations require two environmental surveys post Cessation of Production (CoP). These surveys may however occur in the period between CoP and PP&A, and the closest test stations are generally located 250 meters from the wells. Environmental surveys carried out that far from the well, and possibly prior to PP&A, influence data quality. We argue that the environmental survey data claiming zero leakage, lack sufficient evidence. Thus, based on the reviewed literature outlining the current environmental survey practice, although PP&A well design on the NCS should build on sound principles, we are not able to conclude on the assumption of zero leakage. The interest in risk-based PP&A approaches is increasing globally, and risk-based approaches rely on credible leakage calculations. The failure rates used in these leakage calculations should be based on quality data. The NEA report and other literature indicate that the quality of post PP&A leakage data on the NCS is questionable, and in some cases the data are non-existent. The paper includes suggestions on how to improve the regulatory practice related to environmental surveys.