Temporary Abandonment with MLS & NORSOK

Dear All

BACKGROUND:

We are in planning phase of an offshore well which will be suspended with MLS for at least 7 years (long term suspension) and after re-entry, it will be taken into production. We will do the temporary abandonment in such a way that it would qualify all requirements of P&A (1 primary and 1 secondary cement barrier for HC isolation and 1 surface cement plug, TOC at all casing annulus is designed to be just below MLS), except cutting of conductor stump from sea bed. Monitoring of well barrier (annulus pressures etc.) will not be possible with MLS so it will be a case of temporary abandonment without monitoring. Now I would like to highlight some points from NORSOK standards which are really concerning to the project.

NORSOK STANDARDS:

"Temporary Abandonment – without monitoring: Well status, where the well is abandoned and the primary and secondary well barriers are not continuously monitored and not routinely tested. The maximum abandonment period shall be three years.”

“There is no maximum abandonment period for wells with monitoring.”

"For temporarily abandoned wells without monitoring, the WBE material(s) shall have sufficient integrity to meet the planned abandonment period."

Open hole to surface well barrier is not a requirement in NORSOK for temporary abandonment well. However, we are still doing to cover the qualification of being permanent P&A candidate (only cutting is required which can be done without rig).

QUESTIONS:

1. In our case, where we are following all the guidelines of permanent P&A with cement plug and surface cement plug with all integrity checks and 360 degree coverage, instead of using any mechanical barrier. Would my well still be subject to temporary abandonment which is valid for 3 years? just for the sake that I dont cut the conductor stump. I see it quite absurd because later on if I just go for permanent P&A, I only need to cut the conductor stump from sea bed and the barriers are valid for indefinite period. However the same barriers are not valid if I declare the well as “temporary abandonment without monitoring”
2. Is there any possibility of monitoring offshore well with MLS? This gives me leverage to have no limitation in abandonment period.
3. Or is there a way out that can prolong my TA period? Or dispensation from this standard is the only option I have!

Thanks in advance.

Best Regards,

SK

Documents uploaded by user:

Temporary Abandonment Well Sketch.jpg

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