WORKERS say they can't afford time off work, with rumours the sites could be closed for up to three weeks.
Their complaints about the new Enterprise Bargaining Agreement surround the conditions, rather than pay.
The Observer spoke to several Bechtel employees who wanted to remain anonymous for fear of retribution on their jobs. One worker said he didn't mind the pay rates, but the conditions needed changing.
"The local guys are doing massive days travelling on the ferries and not getting anything for their two hours of travel a day," he said.
Another worker who's been on the island for two years agreed that there wouldn't be many people who could afford not getting paid. "I'm more concerned about the future," he said.
"If this agreement doesn't go in favour of the workers, nothing will improve.
"Things get dearer, but we'll stay exactly as we are. It's not the pay - its things like the FIFO roster - it's one of the only jobs still with a 4/1 roster. Most are 3/1.
"They've proposed they will change it at the end of the next agreement which is in four years-time when all the jobs will be over."
He said for locals travelling on the boat, "we're leaving home at 5am in the morning and 6pm at night.
"It's a long day considering we only get paid 10 hours," he said.
He said the motelling issue was where the fly-in fly-out workers who lived on the island go into different rooms each time they return from their rest week.