Safety-related concrete has been poured for the basemat of the first of two AP1000 units at the VC Summer plant in South Carolina. The milestone marks the official start of construction of the USA's first new reactor in 30 years.
|First concrete is poured at Summer unit 2 (Image: SCE&G)
The basemat provides a foundation for the containment and auxilary buildings that are within the unit's nuclear island. Measuring 1.8 metres thick, the basemat required some 5350 cubic metres of concrete to cover an area about 76 metres by 49 metres. The concrete-pouring process took just over 50 hours and was completed at about 10.00am on 11 March.
The two new 1117 MWe Westinghouse AP1000s will share a site with an existing pressurised water reactor, VC Summer unit 1, operated by South Carolina Electric & Gas (SCE&G), a subsidiary of Scana Corporation, and co-owned by SCE&G and Santee Cooper.
"This major milestone is the first new construction nuclear concrete to be poured in the US in three decades."
SCE&G and Santee Cooper signed an engineering and procurement contract with a consortium of reactor vendor Westinghouse and the Shaw Group in May 2008, and by September 2011 site preparation work was advanced. Shaw was acquired by Chicago Bridge & Iron Company (CB&I) in July 2012.
The Nuclear Regulatory Commission (NRC) issued combined construction and operating licences (COLs) for the two AP1000s at Summer in April 2012. However, the pouring of the first concrete - the recognised event by which construction on a new reactor is deemed to be officially underway - was delayed due to issues with the shear reinforcement for the basemat. SCE&G subsequently requested licence amendments which would "clarify" structural criteria details.
Commenting on the pouring of first concrete, Scana chairman and CEO Kevin Marsh said, "This is an exciting achievement for SCE&G, Santee Cooper, CB&I, Westinghouse Electric Company and others who support our new nuclear project." He added, "We recognize the significance of this event and appreciate the strong commitment to safety and collaboration demonstrated by all involved in reaching this milestone."
Meanwhile, Westinghouse president and CEO Danny Roderick said, "The successful completion of the first concrete pour at VC Summer unit 2 signifies the start of an exciting new phase in the delivery of our AP1000 plants in the United States. It is a milestone of global significance that positions our consortium team to move forward with work on the critically important module installation."
Roderick noted, "As we mark this accomplishment at VC Summer, we continue significant progress on site on the turbine island and balance of plant, as well as operator training for this next generation of nuclear plants."
The first unit is scheduled to enter commercial operation in 2017, and the second in 2018.
The NRC also issued COLs to Southern Company in February 2012 for the construction of two AP1000s at its Vogtle site in Georgia. However, the pouring of first concrete for those two units has also been delayed with issued related to the design and installation of the rebar in the basemats. The NRC rewrote the pertinent licence conditions allowing a concrete mix with higher compression properties to be used.
The pouring of first concrete at Vogtle is expected imminently.
Researched and written
by World Nuclear News