P&A in Arctic conditons

• Main Author: Mehari, Elsa Taeme
• Format: Master Thesis
• Language: English
• Published: University of Stavanger, Norway 2014
• Subjects: petroleumsteknologi; Arctic; p&a; vessel apprailsal; permafrost; gas hydrates; plugging and abandonment; boring; VDP::Technology: 500::Rock and petroleum disciplines: 510::Petroleum engineering: 512; Ice; Iceberg*; Sea ice
• Online Access: http://hdl.handle.net/11250/222302

Master's thesis in Petroleum engineering All oil and gas wells will require plugging and abandonment (p&a) at some point in their operating life. Considering the challenging nature of the Arctic weather, its remoteness and lack of infrastructures, and its ice conditions, conducting this operation in the High Arctic will have the potential to be more costly, time consuming, and challenging. In addition, Arctic weather and ice conditions are difficult to predict. For instance, drift ice cover varies from open waters in the summer to very close drift ice in the winter, but the drift pattern is difficult to predict because of influences from tidal currents and winds (Keinonen, A., et al., 2000). Therefore, it is very important to understand the High Arctic environment so as to get familiar with challenges that can be encountered during p&a operations in the environment. This will make it possible to develop means of conducting safe, and time and cost effective Arctic p&a operations. The thesis presents the challenges and possible solutions for p&a operation in Arctic environments in terms of safety and cost effectiveness. In order to comply with the already established standards, norsok-d-10 rev-4 and ukooa are reviewed. • The study shows that the main challenges of Arctic subsea p&a are associated with the extreme weather condition of the Arctic, Arctic ice conditions such as sea ice and icebergs, and remoteness and lack of infrastructures in the Arctic. Others are spill management problems, p&a vessel challenges, permafrost, and cementing related challenges. • Solutions suggested to these challenges from this study include the need to develop ship-shaped vessels that are enabled for high Arctic operations such as Category A vessels (or the Category I Arctic drilling vessel) with full capabilities for the three phases of well abandonment specified in the Oil and Gas UK standard for p&a operations (Oil and Gas, UK; 2011). Another possibility is to combine the Category A and Category I ...