Atlantic Canada's only nuclear reactor is being gutted and rebuilt, but much slower than initially pledged. (CBC)

The troubled $1.4-billion refurbishment of the Point Lepreau nuclear reactor is suffering another setback, pushing the massive project nine months behind schedule, CBC News has learned.

Sources inside NB Power say the refurbishment of the reactor is being stalled because of problems with the installation of the plant's new calandria tubes. Internal NB Power estimates now show the tubes are to be fully installed by the first or second week of November, nearly nine months late, the sources say.

NB Power did not respond to questions about problems with the calandria tube schedule, but Heather MacLean, a spokeswoman for the utility, did confirm to CBC News in an email that installation has not yet begun.

The utility last issued a public update on the refurbishment five weeks ago, the longest stretch without any official information on the project since it began more than a year ago.

Assembling the calandria tubes is the first step in reconstructing Atlantic Canada's only nuclear reactor.

The 380 tubes — which contain pressure tubes that in turn hold the uranium fuel bundles — were originally scheduled to be pulled out last Christmas.

Point Lepreau is the first Candu-6 reactor to undergo a complete gutting and rebuild. It was intended to be a showcase for AECL to display its ability to revive the 1980s-era reactors.

When the refurbishment project started, it was supposed to last 18 months and have the reactor back on line in October 2010

Delays costing $20M a month

However, crews at Point Lepreau struggled to deconstruct the old reactor, finally finishing that stage in late July, almost eight months behind schedule.

NB Power has acknowledged delays at Point Lepreau will cost $20 million a month.

The delays have come despite several NB Power officials, including David Hay, the utility's president and chief executive officer, confidently pledging just last year to keep the refurbishment "on time and on budget".

Gaetan Thomas, the utility's vice-president for nuclear, predicted last April after the job fell five months in arrears that the pace would pick up.

Thomas said the utility could make up some of the delays because AECL had more experience putting nuclear plants together than pulling them apart.