Kim Jacobs has blown her stack over the $3 billion NorthConnex project.
The southern emissions stack of the twin nine-kilometre tunnels look to be built about 500 metres from her home in West Pennant Hills.
But she worries residents won't have enough time to digest the environmental impact statement, released on Tuesday, and build a case to fight it.
"The public are given only 60 days to read, understand, comprehend and object to the EIS," Ms Jacobs said.
Speaking on behalf of local residents, she said the review period needed to be extended to at least 90 days.
"We don't have an issue with a tunnel — it's a great idea to sort out the traffic problem on Pennant Hills Road," she said.
"What we do have an issue with is the potential health effects of an unfiltered stack being placed where it is proposed — on the residential side of Pennant Hills Road, in close proximity to residents, schools and businesses."
These concerns were not shared by Christine Cowie, a research fellow at The Centre For Air Quality and Health Research and Evaluation.
Dr Cowie said air quality would likely improve near where the NorthConnex motor tunnel ventilation stacks are being built at West Pennant Hills.
She said her previous research into the health of people living near the Lane Cove Tunnel ventilation stacks showed no increase in air pollutants.
"We did see an improvement in air quality very close to the road, but this didn't translate to a change in any respiratory health outcomes," she told the News in March.
Ms Jacobs said the southern stack should be relocated at the most efficient point as identified by the engineers, which is above the southern exit point of the NorthConnex tunnel.
While this may require the acquisition of some of Pennant Hills Golf Club's land, it would also put more trees in the immediate vicinity of the stack, she said.
"It would also raise it considerably and, with the particulates being released at a higher altitude rather than low and into a valley, there would be a much greater chance of dispersion," she said.
"Filtering that is policed to ensure it is turned on and operating every day would also help."
A northern stack is proposed for Wahroonga.
The Hills and Ku-ring-gai council areas will also be affected by the new motorway tunnel which is expected to open in 2019.
The federal government is contributing $405 million to deliver the three-lane tunnels.
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View the environmental impact statement
The public can view, and comment on, the EIS until September 12:
■ In local electorate offices;
■ At the councils of Gosford, The Hills, Hornsby, Ku-ring-gai, Parramatta and Wyong;
■ At the Department of Environment and Planning;
■ At the Nature Conservation Council of NSW;
■ In the Roads and Maritime Services’ North Sydney office; and
■ At the community information office on Pennant Hills Road.
Public air quality forum
A public air quality forum will be held on July 29 at Hornsby RSL from 7pm, following representations from Hornsby MP Matt Kean and Kuring-gai MP Barry O’Farrell. It will include expert speakers who had input into the EIS.
NorthConnex M1-M2 Project
The project is for the construction and operation of a multi-lane road link between the M1 Pacific Motorway (formerly the F3 Sydney-Newcastle Expressway) at North Wahroonga and the M2 Hills Motorway at Baulkham Hills, on land in the suburbs of Hornsby, North Wahroonga, Wahroonga, Normanhurst, Thornleigh, Pennant Hills, Beecroft, West Pennant Hills, Carlingford, North Rocks and Baulkham Hills.
Benefits of the NorthConnex project, according to government:
■ Bypasses 21 sets of traffic lights on Pennant Hills Road, saving up to 15 minutes’ travel time;
■ Avoids 40 traffic lights along the Pacific Highway, from the M1 to Sydney Harbour Bridge;
■ Enables motorists to drive from Newcastle to Melbourne without encountering traffic lights;
■ Takes about 5000 trucks off Pennant Hills Road;
■ Offers connections to Pennant Hills Road at either end of the project;
■ Links to the Sydney Orbital network.
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