BSI was contracted by an operator to eliminate annular pressure on the 16” x 20 (155 psi) and 20” x 30” (150 psi) annuli on an injection well being abandoned in Wyoming.

The well was previously bullheaded with a low-viscosity off the shelf sealant offered by a major service provider, but it was unable eliminate annular gas flow.

TOC was identified .5-2” below the casing head ports. The well was then flushed clean to access leakage pathways using fresh water and surfactant.

Injection began on the 16” x 20” annulus. A series of stages were squeezed into the leakage pathways, with pressure held constant as rate decreased, indicating sealing. At the conclusion of treatment the rate was reduced 96% and pressure was completely eliminated the following day.

Injection followed on the 20” x 30” annulus. 5 stages were pumped over the course of 1 day with rate reduced 96% and pressure eliminated. A few days later pressure built to 80 psi. To facilitate fluid access further into leakage pathways, acid was pumped from surface, after which injection of biomineralizing fluids resumed. Treatment lasted 4 days, at which point rate had been reduced 99% and pressure was eliminated.

The well was monitored for 90 days before being approved for permanent abandonment by WOGCC.