PORT FOURCHON (AP) — State officials on Thursday began sealing a gas well that started leaking several days ago in the Gulf of Mexico off the Louisiana coast.

The process, which began after federal officials gave their approval, involves pumping drilling fluid into the well, said Eileen Angelico, spokeswoman for the Bureau of Safety and Environmental Enforcement. Angelico did know how long it would take.

The well is at a production platform owned by a subsidiary of Houston-based Talos Energy, about 75 miles southwest of Port Fourchon.

Company officials said it had been out of production for years and was being permanently plugged when it began leaking small amounts of gas and an oil-water mixture called condensate.

The Coast Guard said a small sheen was visible on the Gulf surface, but company officials expect it to evaporate.

The well did not suffer a blowout, and there was no explosion, the Coast Guard said.

The Talos platform sits over three wells in water 144 feet deep. Production from the other two wells was shut down after the leak was found on Monday. A small number of workers on the platform were safely evacuated.

Talos obtained the site when it acquired Energy Resources Technology GOM in February.

BSEE and Coast Guard authorities were stationed on a nearby platform to monitor efforts to seal the well leak.

The Talos site is to the west of BP PLC’s Macondo well, which blew out in April 2010. An estimated 200 million gallons of crude oil escaped the well before it was capped. The Macondo well was about a mile under the Gulf surface.

Coast Guard officials said the Talos incident is nowhere near the scope of the BP event.