Negative Other LL with DNO

Oselvar (A-1 H, A-2 H, A-3 HT2) – P&A

PSA Finding

• Deviation from NORSOK related to the verification of barriers when common well barriers are in use.
• The company lacked internal governing documents containing rules of barrier verification when using 9 5/8″ csg. cmt as a common WBE.
• A FIT was used to verify 9 5/8″ casing cement as a permanent barrier.

PSA Comments

Risk/oppertunity:
• Successful cement jobs and subsequent cement bond logs in reference wells can, according to NORSOK, count as verification for the actual well, if the cement job is similar. (In this case, the reference wells could boast good volume control, centralized casing, thorough cement calculations and good CBL logs).

Comments:
• NORSOK D-010 15.22 G states that casing cement used as both primary and secondary barrier counts as critical cement and shall be tested/verified as such. When using common WBE, the cement plug shall be dressed off and casing cement shall be logged.
• NORSOK D-010 15.22 D1 states that the cement sealing capability can be verified through an FIT, but can ONLY be used as a WBE for next section drilling and never be used as verification for permanent abandonment (ref. NORSOK D-010 15.22 D2c).