Georgia Power announced that the recent placement of the nuclear reactor vessel inside one of the two units under construction at Plant Vogtle is a sign of progress in the beleaguered project.

The nuclear reactor vessel will serve as the heat source, producing steam for power generation once the unit comes online.

The latest milestone in construction at the site follows the pouring of 2,400 cubic yards of concrete on the unit’s turbine tabletop early this month.

Construction at the site, the only active new nuclear build in the U.S., is being managed by Southern Nuclear, a subsidiary of Georgia Power’ parent company Southern Company.

Georgia Power says progress has improved since Southern Nuclear took over construction management from Westinghouse Electric Co., which went into bankruptcy last March.

The project, which is billions over budget, is five years behind schedule and is expected to be complete in 2022.