Investigation Report
Glycol and Seawater Release Through Subsea Valve During Well Abandonment
03-18-2022 1800 G19409 AC 815 Pollution
- BSEE
- Investigation Report
- Unknown
- Environmental protectionLoss of containment
- Pressure testingROV operationsWell abandonment
- Valve
- Functional testingOperating and work proceduresPre-use checks
- Upstream oil and gas
- Marine watersSubsea
Summary
BSEE investigates a Gulf of Mexico pollution incident during coiled-tubing well abandonment. Approximately 188 barrels of a 50/50 mono ethylene glycol and seawater mixture escaped through a subsea tree valve. Findings identify unverified valve alignment and inadequate closure-verification procedures; ROV intervention and subsequent pressure testing restored containment.
Classifications: Environmental protection; environmental safety; pollution prevention.
Classifications: Loss of containment; containment loss.
Classifications: Pressure testing; hydrostatic testing; pneumatic testing.
Classifications: ROV operations; remotely operated vehicle operations.
Classifications: Well abandonment; plug and abandonment; P&A.
Classifications: Valve; valves.
Classifications: Functional testing; function test.
Classifications: Operating and work procedures.
Classifications: Pre-use checks; pre-use inspection.
Classifications: Upstream oil and gas; oil and gas extraction; upstream petroleum.
Classifications: Marine waters.
Classifications: Subsea; underwater worksite.