Assessment of Casing and Cement Quality for P&A
Why P&A?
When a field or a well is depleted or not economical to produce anymore or not suitable for further use, it needs to be plugged and abandonned.
Before plugging the well in the subsurface, the state of the casing and the cement bond around it needs to be evaluated. The well might have been active for decades and the original well planning might be lost or certain measures have not been properly documented. Also regulating authorities want to see a good documentation of the current state to be able to approve the P&A measures.
Plugging and abandonning (P&A) means to seal the well inside, to remove the casing near the surface and to decommision the surface installations, to restore the original environment and to return the land to its owner.
NiMBUC’s services
We help our customers with the assessment of the casing and the cement bond logs (CBL). These acoustic tools record the status of the well and the resulting plots are evaluated. They contain information about:
- Diameter of well sections and according depths,
- Status of casing,
- Whether the casing is bonded to the cement and how good,
- Whether the casing is not cemented (free pipe),
- The quality of the cement, i.e. the bonding to the formation and if any fluids are present.
