The official word is being kept under wraps, but there are signs a big project is coming to the Irving Oil refinery.

The annual maintenance shutdown at Canada’s largest refinery is always a welcome project for local workers, and this year the anticipation is even greater given the prolonged slump and lack of jobs in the local construction industry.

Though the company isn’t commenting, trade unions like the boilermakers say this year’s maintenance turnaround will be among the more extensive Irving Oil has done.

“This is a really big project,” said Kim Blyth of Boilermakers Local 73.

"The Boilermakers are looking at between 450 and 500 members. The full scope of everything is probably about 3,000 construction workers over and above the regular workforce,” he said.

The local labourers union told CTV News they expect a call for about 600 workers — far more than what’s required for the usual maintenance turnaround.

Most of the work is expected to be done in a 60-day period, with employment numbers peaking in October.

Preliminary work, though, is already underway, with new trailers, tents and equipment visible on the site.

"Well that's all part of the ramping up,” said Stephen Beatteay of the Saint John Construction Association.

“They have to do the infrastructure for the lunch trailers and the time clocks and the other facilities … that doesn't take place when (the workers) come through the door,”

With files from CTV Atlantic’s Mike Cameron