A team that reviewed Southern Nuclear Company’s (SNC’s) April 2019 Vogtle Units 3 and 4 Re-baseline of Forecast Schedule and Cost said it believes the working schedule predicated on commercial operation dates of May 23, 2021, and May 23, 2022, for the respective units, is unachievable. Furthermore, the reviewers said the regulatory-approved schedule from the 17th Vogtle Construction Monitoring Report, which projects commercial operation to begin in November 2021 and November 2022, respectively, “will be a challenge to achieve.”

The findings were conveyed by the Georgia Public Service Commission Public Interest Advocacy Staff in a report filed on July 30. The team noted that “the means and methods used” by SNC to develop the April 2019 project baseline were generally sound, but evaluators felt approaches taken to meet the aggressive schedule were filled with delay risks and inconsistent with the staff’s collective experience in nuclear and large plant construction. Specifically, the reviewers said a “premature focus on systems testing and turnover prior to achieving a greater percentage of the construction of bulk electrical and mechanical commodities” could quickly erode the roughly six-month schedule contingency.

The staff noted that many high-probability schedule and cost risks have been identified and are being tracked by SNC, but the team said few were incorporated into the integrated project schedule. Nonetheless, the review team said “there is a chance” the project will meet the existing cost schedule, which was pegged at $17.1 billion for all owners, excluding financing costs, in the April 2019 baseline forecast.

Southern Company Chairman, President, and CEO Tom Fanning, during the company’s second quarter earnings call on July 31, didn’t sound confident of meeting the aggressive site work plan either.

“The aggressive site work plan is challenging, and we work to meet it every day. Ultimately, success is bringing Vogtle Unit 3 and 4 online on or before the regulatory-approved November 2021 and 2022 in-service dates,” Fanning said. “Based on what we know today, we continue to expect that we have sufficient schedule and cost contingency to meet this objective.”

Fanning said costs were being held in check, yet he noted unexpected increases were likely to arise. “There is no change in our total estimated costs for the project at this time, and we have not allocated any contingency, though the presence of a contingency reflects our expectation that we will likely utilize this reserve in the months ahead,” he said.

Fanning indicated that several milestones were achieved in May. He said the site completed initial energization of Unit 3, which was a major step for the project. In addition, the middle containment ring for Unit 4 (Figure 1) was set and the generator rotor was installed in Unit 3.

1. Recent milestones achieved at the Vogtle site include the setting of the middle containment ring on Unit 4, shown on the right of this image. Courtesy: Southern Company

“In August, we expect to begin our next major milestone for Unit 3—integrated flush activities—on schedule with the site’s aggressive work plan. Overall, including engineering, procurement, and initial test-plan activities, the entire project is approximately 79% complete. For Unit 3, direct construction is 71% complete with a target to approach 90% by year end,” Fanning said.

In 2019, the site has averaged approximately 133,000 earned hours per week through July. However, Fanning said the aggressive site work plan requires an average of 160,000 weekly earned hours for a sustained period of time starting later this year into 2020. Still, to meet the regulatory-approved November schedule, the company only needs to average about 100,000 earned hours per week through the start of Unit 3 hot-functional testing, which is essentially the completion of the construction phase for the unit, Fanning said.

“We have been successful in hiring additional craft resources and supervision, and now we have over 8,000 people working on the site across day and night shifts. As a result of these hiring efforts, construction’s weekly production capacity has risen and we are working to gain productivity improvements,” said Fanning.

Looking forward, SNC expects to be near completion of the integrated flush for Unit 3 and to have the main control room ready for testing by the end of the year. Around the same time, the site should begin open-vessel testing. Open-vessel testing verifies that water flows between the primary systems and the reactor, and that the pumps, motors, valves, and pipes function as designed. This is a key set of activities leading up to cold-hydro testing, which is expected to begin next spring. The final major construction milestone is the start of hot-functional testing, after which the primary focus will be on certifying systems leading up to fuel load, which would occur by the end of 2020 under the aggressive site work plan.

2. Vogtle Unit 3 direct construction and major milestones. Source: Southern Company Second Quarter 2019 Earnings presentation

Southern Company announced on July 30 that it had ordered fuel for Unit 3. The reactor will contain 157 fuel assemblies, each measuring 14 feet tall.

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