Georgia Power logo. (PRNewsFoto/Georgia Power)Georgia Power has completed cold hydro testing for unit 3 of the Vogtle nuclear plant, the first Westinghouse AP1000 to be built in the USA.

Vogtle 3 is now approximately 94% complete, with the total Vogtle 3&4 expansion project approximately 88% complete, Georgia Power said. The completion of the cold hydro testing milestone prepares the site for the last major test remaining for Vogtle 3, hot functional testing, ahead of initial fuel load.

"Completion of cold hydro testing not only helps pave the way for initial fuel load, it also moves us closer to bringing online a carbon-free asset that will provide clean energy for our customers, our state and the country for the next 60 to 80 years," said Paul Bowers, chairman, president and CEO of Georgia Power.

Cold hydro testing of Vogtle 3 confirmed the reactor's coolant system functions as designed and verified the welds, joints, pipes and other components of the coolant system and associated high-pressure systems do not leak when under pressure. As part of the testing, the reactor coolant system was filled with water and pressurized above-normal operating conditions, then lowered to normal design pressure while comprehensive inspections were conducted to verify the systems meet design standards.

Georgia Power continues to expect to meet the November 2021 and November 2022 regulatory-approved in-service dates for Vogtle 3 and 4, respectively.

The company added that the first reactor coolant pump (RCP) had been started up at unit 3, marking a first for both the project and for an AP1000 in the USA. This initial run verifies the RCP operates as designed. During operations, the RCPs will circulate water through the reactor vessel and steam generators, providing forced flow of the reactor coolant through the reactor core, to the steam generator and then back again to support operations.

In addition, the Nuclear Regulatory Commission (NRC) has issued the first operator licences to 62 Reactor and Senior Reactor Operators for Vogtle 3&4. The multi-year process for obtaining an operator licence begins with extensive training in reactor theory, thermodynamics and system operation in the classroom and field. The operators spend months in the Main Control Room simulator running various scenarios under normal and emergency conditions to help ensure that the operators can safely respond to any issue or event. This process culminates with a two-week examination administered by NRC.

Construction of the two units at Vogtle began in 2013. Southern Nuclear and Georgia Power, both subsidiaries of Southern Company, took over management of the project in 2017 following the bankruptcy of Westinghouse Electric Company that supplied the AP1000 reactors.