The highly anticipated Epping to Chatswood rail line has been hit with another hiccup with trains set to travel through the underground tunnel labelled 'too noisy.'
The problem was picked up six months ago, when the first train ran through the 12.5km tunnel.
The situation's been made worse by the steepness of the tunnel, meaning quieter Tangara trains can't be used.
Instead RailCorp intended to use the 30-year-old K-set rolling stock trains, already overdue for retirement, on the line.
However the noise levels in these trains, which were never intended to be used underground, breached RailCorp's standard for commuters, meaning they also had to be ruled out.
RailCorp spokesman Paul Rea told Fairfax there would be no delay to the proposed February opening of the line, but said the type of trains used would have to be reviewed.
"The initial operation of the [line] will be a shuttle service using RailCorp's OSCAR [outer suburban] trains which will meet targeted levels of passenger comfort," he said.
The rail line has already missed its original 2006 opening date, despite being cut in half after plans for a line all the way to Parramatta were scrapped in 2003.
Despite this the original estimate of $1.4 billion for the stretch to Parramatta has blown out to $2.3 billion for the much shorter line to Epping.
The news come as another embarrassment for the Rees government, already rocked by poor by-election results.
The rail line is the state's biggest infrastructure project and it was hoped its completion would provide a much needed boost the Labor's credibility in NSW.