PORT GIBSON — Work is ongoing at the site of the Grand Gulf Nuclear Station, which has been disconnected from the power grid as part of a planned maintenance outage.

The outage at Grand Gulf is being done for equipment and parts upgrades, and to replace one-third of the fuel in the reactor. Grand Gulf Spokeswoman Suzanne Anderson said the nuclear reactor is being refueled with uranium.

Anderson said the work is ongoing, but declined to specify where in the process it is.

“For safety and security reasons, we don’t discuss the timeline or the duration of an outage,” Anderson said.

The process of powering down the plant for the refueling and repairs began Feb. 19. At the time, officials said the outage was expected to last several weeks.

Equipment improvements being completed at the plant include the installation of a new turbine motor and a refurbished main generator. The improvements will increase the stations’ electrical output by 13 percent.

When the repairs are completed and the station goes back online, Anderson said the Grand Gulf Station would be the most powerful nuclear power generator in the country.

Powering up the generator is done in several steps, but Anderson said those steps could not be discussed for security reasons.

“It is very much a process to do it safely and securely,” she said. “At this point I don’t want to speculate how long that will take.”

Nuclear reactors require refueling every 18 to 24 months, and the maintenance work at the station was dovetailed with the routine outage.

Approximately 4,000 workers, including but not limited to Entergy employees, are involved in the outage work at the station.

Anderson said the outage is not affecting Entergy’s customers.

Entergy Mississippi and South Mississippi Electric Power Association jointly own Grand Gulf.