When designing a plug and abandonment (P&A) operation the barrier quality of the casing cement sheath must be assessed such that an optimal P&A solution can be chosen in terms of technical quality and operational cost. Borehole cement evaluation logs are often used for this purpose.
A full-scale facility is being built whereby commercial tools and emerging barrier evaluation technologies can be evaluated. The objective is to provide reference conditions for cement barrier verification experiments. A particular aim of the project is to support the development of technologies for logging through multiple tubulars.
Barrier reference test cells have been constructed representing a range of annular leakage scenarios such as gas channels, mud channels and de-bonded cement. The test cells can be coupled together using quick unions and extensions are available to account for the different logging technologies. The casing and annulus can be pressurized with different fluids and controlled leakage rates can be applied with water and gas.
Experiments performed to date encompass commercial logs, alternative barrier verification technology and an X-ray concept for logging through multiple tubulars. The facility design and operation and experiments executed are described.