The final major module needed to construct Vogtle Units 3 and 4—the only new commercial nuclear power units currently under construction in the U.S.—has arrived at the site near Waynesboro, Georgia. That means all 1,485 major modules have been manufactured and safely delivered to the project.

Georgia Power announced the milestone in a press release issued on Oct. 2. The company said the feat “marks the completion of sourcing construction modules from 25 suppliers and vendors from around the globe.” The modules streamline the construction process, because they are made at various manufacturing locations, shipped to the site, and assembled into larger components that make up the nuclear units.

The modules have been regularly delivered to the site by rail and truck beginning in 2011. They include a range of plant components, such as floor and wall sections, and supporting structures that surround the containment buildings and reactor vessels. A time-lapse video of the CA-01 module—which weighs more than 2 million pounds and measures 70 feet tall, 90 feet wide, and 80 feet deep—being moved from the project’s 12-story module assembly building and placed in the Unit 4 containment in 2016 is viewable below.

Georgia Power said several other milestones were also achieved recently. Among the achievements noted on Unit 4 was the completion of the second of four concrete placements for the operating deck inside the containment vessel. The company said placement of 58 cubic yards of concrete formed a 2-foot-thick floor to support the loading and staging of equipment in preparation for the third containment ring and top head placements on the unit. To date, more than 667,000 cubic yards of concrete have been placed for Units 3 and 4, which is enough to build a sidewalk from Miami to Seattle, according to the company.

Workers also recently set the integrated head package (IHP) on its stand inside the Unit 4 containment vessel. The IHP weighs more than 237 tons, stands 48 ft tall, and contains more than three miles of electrical cables. It sits atop the reactor vessel during normal operation and is “the integral piece used in monitoring and controlling the nuclear reaction” during operation.

There are approximately 8,000 workers on-site, which is an all-time high. Georgia Power said the Vogtle expansion is currently the largest construction project in Georgia (Figure 1).

1. This image was taken last month inside the containment vessel of Vogtle Unit 3. Courtesy: Georgia Power

Aaron Larson is POWER’s executive editor (@AaronL_Power, @POWERmagazine).