Aker BP intends to drill new production wells in this North Sea field, and is planning to use formation clay as a well barrier element.
This approach has primarily been used previously on the Norwegian continental shelf (NCS) to plug wells permanently.
No application to use formation clay as a well barrier element during drilling and the subsequent production phase has earlier been made in the plan for development and operation (PDO) or when seeking consent to drill new production wells.
As part of its consideration of Aker BP’s application for consent, the PSA has held meetings with the company to clarify its overall plans for qualifying and using formation clay.
It also conducted an audit from 25 November to 3 December 2021 of the planning and execution of drilling operations on the Hod field by the company.
The PSA’s supervisory activities have shown that well barriers have not been tested with sufficient independence during drilling of the reservoir sections in the wells.
The PSA considers this a serious breach of the regulations, and has therefore given Aker BP notice of the following order.
Pursuant to section 69 of the framework regulations on administrative decisions, see section 85, paragraphs 1 and 2 of the activities regulations on well barriers and section 48, paragraph 6 of the facilities regulations on the well barriers, we order Aker BP:
– to verify that the formation clay is established and isolating through verification of the well barrier element behind the production casing before drilling the reservoir section of the wells on the Hod B Saddle where formation clay is used as a well barrier element.
The deadline for compliance with this order is the first relevant drilling operation on the Hod B Saddle. We must be notified when the order has been complied with.
Hod is a field in the southern part of the Norwegian sector in the North Sea, about 13 kilometres south of the Valhall field. The water depth is 72 metres. Hod was discovered in 1974, and the plan for development and operation (PDO) was approved in 1988. Production started in 1990.
A PDO for the redevelopment of Hod was approved in December 2020. This involves installing a new wellhead platform tied-in to the Valhall field centre.