Workers are preparing to permanently kill a leaking gas well in the Gulf of Mexico this weekend, after temporarily sealing it off late Thursday.
Specialists plugged the leak by pumping drilling mud into the 40-year-old Energy Resource Technology well late Thursday, roughly four days after it first started discharging a briny mix of gas, light condensate and salt water.
“The flow from the well was completely stopped,” said David Blackmon, a spokesman for ERT, a newly acquired subsidiary of Houston-based Talos Energy. “They’ve been monitoring the well overnight, per guidance from the Bureau of Safety and Environmental Enforcement.”
The next phase in the operation may begin as soon as Saturday evening, once regulators at the Interior Department bureau approve plans to pump cement into the shallow-water well, permanently sealing it off. Thunderstorms and lightning in the area slowed operations Friday, and work was expected to continue through the weekend.
The safety bureau said it was requiring ERT to monitor the well for any changes while its engineers review the company’s plans “to isolate the well’s hydrocarbon zone.”
“A BSEE supervisory inspector is on board the platform monitoring the ongoing site assessment and well analysis,” the safety bureau said in a statement Friday afternoon. “Preparations and work to permanently seal the well are expected to continue through the weekend.”
Industry representatives said damage from the episode is likely to be minimal, chiefly because the old, slow-flowing gas well was already on the verge of retirement. It last produced gas commercially more than a decade ago, and Talos Energy was in the process of permanently plugging and abandoning the well when fluid first started escaping on Sunday. Although it was briefly brought back under control, the leak began again Monday morning.
ERT estimated that in the first days of the leak, the well was flowing at a relatively low rate, with approximately 3.6 barrels of light condensate being discharged every 24 hours. The initial gush of hydrocarbons — and the steady continued leak — was enough to produce a four-mile long light rainbow sheen, but that has diminished since. It was not clear Friday if the sheen was still present.
Unlike spilled oil, which generally must be contained and sopped up to prevent environmental damage, leaked gas evaporates naturally over time.
Dozens of people are involved in the operation, with many stationed at a neighboring platform, about 74 miles from Port Fourchon, La. Coast Guard officials and regulators from the safety bureau also have been overseeing activity onshore. Federal officials said they will conduct an investigation into the incident.
The leaking well is located in 146 feet of water in Ship Shoal block 225. Although Southern Production and Refining Co. first drilled the well in 1973, SONAT Exploration Co. operated it for years after. Energy Resource Technology’s working interest partners in the well include Noble Energy Inc. and Fidelity Exploration and Production Co.
Two other wells at the same production platform were shut in and five workers evacuated the facility on Monday.
Officials with the not-for-profit group On Wings of Care captured video of the spill during a flight over the region on Wednesday. The group has been documenting marine life in the region but said it saw only a few dolphin, some flying fish and a hammerhead shark during Wednesday’s flight “despite mirror-calm seas, excellent water and air visibility and clear blue water.”
Video courtesy of Terese P. Collins with On Wings Of Care: