The Wenona School in North Sydney, the Anzac Park Primary School in Cammeray and the Seaforth Public School are each within 200 metres of the sites chosen for smokestacks to release exhaust fumes from tunnels for the proposed Western Harbour Tunnel and Beaches Link.
The proposed locations, in a cabinet in confidence document seen by Fairfax Media and the ABC, are on residential streets, parkland and the existing Warringah Freeway and Wakehurst Parkway.
The proposed toll road would tunnel from WestConnex at Rozelle to the Warringah Freeway at North Sydney, then tunnel under Middle Harbour to join the Wakehurst Parkway at Allambie Heights.
It is expected to deliver time savings of up to 40 minutes between Brookvale and the city, 45 minutes between Dee Why to the airport and 35 minutes between Seaforth and North Sydney.
The ventilation shafts, each between 20 and 35 metres high, would release fumes from the thousands of trucks and cars expected to travel underground. Each would be accompanied by ventilation plants of between 1500 and 2500 square metres.
The document identifies the key issues with the potential to hold up approval as: potential opposition to the compulsory acquisition of homes from "residents, council and elected representatives", community and/or environmental group opposition to the dredging, haulage and disposal of spoil "particularly if contamination is present", and potential community and council opposition to use of crown land including St Leonards Park, Yurulbin Park, Anzac Park and The Spit Reserve.
Each mapped location is marked with a 150 metre buffer for the "downwash" of pollutants, and a wider 500 metre "sensitivity buffer".
Homes, schools, childcare centres and hospitals identified as "sensitive receptors" are also marked. No location is identified for the Rozelle exhaust stack.
The proposed smokestack sites are:
- Ridge Street, North Sydney, near Wenona School and St Leonards Park
- Falcon Street, St Leonards, near Warringah Freeway
- Cammeray Golf Club, near Anzac Park Public School
- Artarmon Reserve, near Gore Hill
- Dudley Street, Balgowlah, near Seaforth Public School
- Wakehurst Parkway, near Judith Street, Seaforth
"It should be noted that where constraints are related to the close proximity to existing residential receptors, a major risk to the project will be the perceived air quality impacts from ventilation stack outlets, despite air quality outcomes potentially being achieved," the cabinet in confidence document says.
"This perceived impact has been experienced on a number of major motorway projects involving tunnels, including NorthConnex and WestConnex more recently."
It suggests the government consider the relocation of some of the proposed stacks "to adjacent park or bushland".
Dispersal near Wenona School is hindered by tall buildings. Background pollution means the stack may cause "cumulative air quality impacts".
A table in the document points to unsafe levels of the contaminants PM2.5 and PM10 at several of the sites. The microscopic particles have been declared carcinogens by the World Health Organisation.
The level of detail in the document indicates that, as with the proposed F6 Extension toll road in Sydney's south, the "base case" for the project is well advanced. Fairfax Media understands a rail alternative has not been considered.
It raises the prospect of three multi-billion dollar toll roads – WestConnex, the F6 Extension and Western Harbour Tunnel and Beaches Link – undergoing construction at various stages and at about the same time.
Fairfax Media has already published details of the six locations chosen for the F6 Extension smokestacks, one of which is next to Port Hacking High School.
A spokesman for Roads Minister Melinda Pavey said the final alignment of the tunnels had not been determined. Therefore the location of exhaust outlets was yet to be determined.
"Geotechnical work is ongoing to determine the preferred route for the tunnel," the spokesman said. "The community has been and will continue to be informed at all stages."
The cabinet in confidence document recommends declaring the Western Harbour Tunnel and Beaches Link "critical state significant infrastructure" in order to bypass objections.
NorthConnex and WestConnex were declared critical state significant infrastructure.
The declaration would prevent appeals to the Land and Environment Court without the agreement of the planning minister and prevent the making of certain orders under the National Parks and Wildlife Act, the Threatened Species Conservation Act, Fisheries Management Act, Protection of the Environment Operations Act and the Local Government Act.
"Based on a preliminary consideration of the project, it is likely that a reasonable argument could be formulated to support the necessary view to be formed by the minister for planning that the project is essential to the State for economic, social or environmental reasons as a preceding step to declaration of the project as Critical State Significant Infrastructure," the report says.
In The Age and Sydney Morning Herald