However, Roads Minister Duncan Gay said residents, who live as close as 200 metres from the location, had nothing to fear.

He said, not only would they experience ‘‘no measurable change in air quality’’, the surrounding area would have cleaner air than at present because traffic flow would improve.

Mr Gay stood with Senator for Western Sydney Marise Payne with and project executives near the M5 East tunnel entrance at Arncliffe to announce more design details of the new M5 tunnel and the preferred contractor.

Behind them, traffic was at a near standstill, and there was constant sounding of horns by frustrated truck drivers.

‘‘I think they are telling us to get on with it,’’ Mr Gay said.

Leighton Dragados Samsung Joint Venture was selected as the preferred tenderer for the work, which is stage two of WestConnex.

Two of these companies, Leighton and Samsung, are also partners in building stage one.

The 9km long tunnel from Kingsgrove to St Peters will cost about $5 billion, which Mr Gay said was ‘‘spot on’’ what the state government had planned.

It will accommodate three lanes in each direction, but initially will be line-marked for two lanes.

There will be no extra entry or exit points, apart from provision for the possible future connection of a southern extension from Arncliffe to Kogarah.

As previously stated, there will be no impact on Wolli Creek bushland and Tempe wetlands.

Dennis Cliche, chief executive of Sydney Motorway Corporation, which is managing the project, said exhaust stacks would be located at Kingsgrove, Arncliffe and St Peters.

He confirmed Kogarah Golf Course, which had previously been identified only as a possible site, would have one of the stacks.

It will be located in the north-western corner of the golf course, which will also be a construction site.

Mr Cliche said the design of the stacks had not been completed but, typically, they were about 35 metres high.

He said filtration was unnecessary.

‘‘We have done extensive studies and the design of ventilation outlets today achieve better results without filtration,’’ he said.

Mr Cliche said, once the tunnel was operating, ‘‘air quality will be as good as it is today’’.

‘‘Every year, the quality of the vehicles is improving and there is less pollution,’’ he said.

‘‘By having tunnels without stop-start traffic, you are improving the quality of the air.’’

Mr Gay said smoky vehicle detectors in the M5 East tunnel, accompanied by increased fines, had made ‘‘a huge difference’’ to air quality.

Traffic management at the St Peters interchange will include:

■ Euston Road will take motorists to areas such as the southern part of Alexandria, Green Square and Redfern.

■ A new bridge will be built across the canal to Gardeners Road, to link with Mascot.

■ Campbell Street/Road will take traffic towards St Peters and Marrickville.

Do you accept the promises about air quality?