LL with DNO

Kjøttkake (35/10-13)

What happened:

POOH and commenced drilling 26” hole section with RMR. After 20” casing was set and BOP ready to land on HPWHH, the ROV discovered a big crater around the conductor. Poor visibility at seabed, meant we were not able to spot the crater until the dust had settled enough (seabed current in play).

What was planned:

POOH with cement fiberglass inner string after WOC for conductor cement job.

What was learned:

Always plan to tag cement behind conductor with fiberglass stinger after releasing with WHRT to confirm cement returns to seabed. Could be an option to plan for using 5 7/8” DP inner string instead if fiberglass, if concern of fiberglass breaking when setting down weight.

The benefit of tagging cement behind conductor is that we are able to do a grouting job (or similar) before drilling the 26” section, and crucially before the BOP is run.

What actions are required:

Tag cement behind Conductor with fiberglass stinger after releasing with WHRT.