In an unconventional field with known water flows due to injection zones, an intermediate hole section was drilled to TD and casing ran until stuck off bottom, all while managing water flow with mild H2S. The casing was cemented in place with no returns
to surface, float was bumped and held differential pressure. At 50 psi compressive strength development after ~18 hrs post cement placement, intermittent water flow with shut in casing pressures necessitated higher compressive strength development wait time.
After WOC for 32 hrs to achieve 500 psi compressive strength with no flow observed, the BOP was lifted to install the emergency slips and pack-off. ~3 hours into this operation, flow was observed and the team reinstalled the BOP and secured the well with
57 psi shut in casing pressure and 60 bbls water influx gained. Pressure was bled off to zero and well was monitored for ~2hrs with no flow but observed to be on vacuum.
The annulus was filled with 15.5 ppg mud and decision was subsequently made to squeeze the annulus with 14.8 ppg cement slurry which was performed in three stages. After the squeeze job, the well was flow checked for 1hr with no flow. BOP was then nippled
down, emergency slips and packoff were installed and tested to establish barriers to annulus flow.
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