The refurbishment of Point Lepreau, Atlantic Canada's only nuclear reactor, is three years behind its original schedule. (CBC)

The installation and testing of all 380 calandria tubes in the reactor vessel has been completed in the $1.4-billion Point Lepreau refurbishment, according to a NB Power news release out Friday.

The tubes were the first major pieces of equipment to be installed in the reactor as part of Point Lepreau's refurbishment.

But 80 of the tubes flunked air tightness tests earlier this year after being fused with special inserts designed to hold them in place.

"The installation and testing of each calandria tube was complex and very precise work," said Rod Eagles, NB Power Refurbishment project director in a news release.

"The dedication of the combined NB Power and AECL team has allowed us to remain on track to meet the May 2012 completion date."

The calandria tubes were tested individually at each end to ensure leak-tight seals and all tests were successful.

The tubes are approximately six metres long and 13 centimetres in diameter, and will contain the reactor's fuel channels and fuel bundles.

Workers are preparing for the fuel channel installation activities, which are expected to be completed in December 2011.

The next step will include the installation of pressure tubes, spacers, end fittings and positioning assemblies as well as bellows welding.

The refurbishment of Atlantic Canada's only nuclear reactor is three years behind its original schedule. It was originally to be completed in September 2009.

It is estimated that NB Power spends $1 million a day to purchase replacement fuel for each day the nuclear reactor is delayed.