RockSolid™ Barrier verified by BVS
The BVS validated the RockSolid™ thermite barrier’s integrity during Plug & Abandonment, detecting no leaks through it but identifying failure in the resin plug above. Pressure monitoring revealed caprock communication, proving the BVS essential for verifying sealing performance and providing critical pressure behaviour insights.
Region
Year
Challenge
This case study focuses on the application of the Barrier Verification System (BVS) during the Plug & Abandonment (P&A) operation. The primary objective of the BVS was to evaluate the integrity of the RockSolid™ based barrier by monitoring pressure behaviour, assessing sealing performance, and identifying potential leaks.
The main goal was to utilise the BVS to:
- Verify the integrity of the thermite barrier.
- Detect any pressure communication across the barrier.
- Conduct inflow and pressure drawdown tests to confirm sealing
effectiveness.
Solution
1. Initial Setup and Deployment
A BVS transmitter was attached below the packer and installed at the bottom of the barrier interval. Heat shield material was dumped on top of the packer, and the thermite barrier was installed above it.
2. Post-Thermite Barrier Installation Monitoring
After the thermite barrier was installed, a BVS receiver run was performed to confirm communication with the transmitter below. The maximum distance where the receiver picked up a signal was measured to be approximately 14 m.
3. Positive Pressure Test (70 bar)
A BVS live readout monitored the test, showing no pressure increase below the thermite barrier, validating its integrity. A 6.3 bar pressure loss was detected above the plug, suggesting potential fluid movement into the caprock, but no breach of the thermite barrier.
4. Inflow (Negative Pressure) Test with Pressure Manipulation Tool
The BVS monitored a controlled pressure drawdown between the thermite and a ME bridge plug. Initially, no significant pressure drop was detected in live data; however, memory data from the BVS revealed a 19 bar drawdown before pressure equalised due to backflow from the caprock. This confirmed that, while the thermite barrier held pressure, the resin plug above did not fully seal.
5. Final Verification with Pipe & RTTS Packer
A final BVS memory receiver run confirmed pressure stability below the thermite plug. Positive pressure tests showed 16 bar pressure drop, reinforcing evidence of leakage through the resin plug rather than the thermite barrier. Inflow tests with a smaller volume resulted in a 64 bar pressure increase, confirming caprock pressure influence.
Value Created
- The thermite barrier successfully held pressure, as validated by the BVS monitoring.
- The resin plug above the thermite barrier failed, allowing pressure communication with the caprock.
- The BVS proved essential in evaluating barrier integrity, providing crucial
insights into pressure behaviour.
Benefits of BVS:
- Capable of verifying integrity of an installed well barrier real time
- Reduces time taken to verify barrier
- Verification is achieved through pressure and temperature readings both below and above the barrier
- Wireless transfer of well
information
Benefits of RockSolid™
- Patented formation-toformation barrier
- Restores the cap-rock formation to its original integrity
- Simplifies Single-trip e-line deployment system