A historical development of P&A requirements on the NCS and its effects on permanently plugged and abandoned wells

Abstract

This master thesis presents the development of the regulation in the field of permanent plug and abandonment in the Norwegian Continental Shelf (NCS). It describes how the regulations have been developed for Permanent Plug and Abandonment (P&A) and focusing on effects of regulations since 1967.

The overall aim of the work is to highlight major changes in the regulations and assess the effects on the oil and gas industry in Norway. In addition, I am focusing on the barriers and barrier management in P&A operations and how the operating companies in Norway implemented and complied with the requirements.

The first chapter of the thesis is a general introduction to regulations and standards related to the P&A in the NCS. The second chapter describes the development of the regulations and describes the main actors in developing these requirements. While the third chapter describes the historical developments in details from the first issued regulation to the establishment of the NORSOK standard D-010 with specific focus on drilling activities and well activities.

The fourth chapter describes the major changes in NORSOK D-010 and describing the major changes in details.

The fifth chapter is focusing on the barriers, well barriers and well barrier acceptance criteria, and defines how the Norwegian management regulation section 5 is emphasizing that the barriers shall be established at all times. The sixth chapter of the thesis is highlighting the data selection process and present the scope of P&A activities by fields and major operating companies in NCS.

The analysis part in chapter seven is focusing on the effects of the changes in regulation on issues related to; integrity, HSE, costs, effectiveness, resource utilisation and the need for the technology development in the field of P&A.

The eighth chapter is the discussion part where I have interpreted and described the significance of the findings and the effects on the operations in the field of P&A: The chapter is explaining the developments in the regulation, challenges and main actors in the field. The primary source of data, information on wells and well status discussed with the currently available knowledge in the field.

This thesis provides the overview of the changes in regulations, the need for more in-depth research in the field in the future. As it is presented in chapter nine for conclusions, the presenting findings are based on my experience with gathered data, communications with major oil and gas operating companies and with Norwegian Petroleum Safety Authorities. The finding from the thesis is clearly indicating the possibility for improvements in data quality, feedback from industry to students and researchers as well as evaluating the need for establishing a monitoring system for all permanently plugged wells.