The Bureau of Safety and Environmental Enforcement (BSEE) determined equipment failure resulted in loss of almost 500 bbl of oil in a 2020 oil spill. The report, released March 8, found that fractured studs resulted in a flowline failure in a Fieldwood Energy-operated deepwater Gulf of Mexico field. Following its emergence from bankruptcy in September 2021, the company now operates as QuarterNorth Energy.

The incident occurred on the Katmai Field Well #1 on July 24, 2020. The well is located approximately 140 miles offshore Louisiana in Green Canyon Area Block 40 in 2,082 ft of water. The leak, which resulted in a loss of 479 barrels of oil, occurred when a flowline jumper failed and four flange fasteners fractured.

The investigation, conducted by BSEE experts and specialized investigators, found that the jumper and flange failures were the result of fractured studs. According to the report, the studs were composed of a corrosion-resistant nickel-based alloy, but the alloy was susceptible to hydrogen embrittlement in subsea environments. Another contributing factor to the leak was a gap in the quality assurance/quality control process that allowed for a non-compliance subsea flange fastener installation. Fieldwood’s methods for immediate subsea leak detection were also found to be limited with the flowline shut-in as there were inaudible subsea alarms, and seemingly no control room operator to monitor subsea components in the control room, according to the report. While these faults did not contribute to the jumper failure, they did impact the timeliness of response to the failure.

As a result of its investigation, BSEE issued a safety report that recommends that operators and contractors use an industry-knowledgeable metallurgist to evaluate all subsea fasteners to verify their suitability for usage in subsea environments. They also emphasize that all company, contract, and sub-contract personnel enact management of change protocol when there are modifications associated with equipment, personnel, operating procedures and operating conditions.