Premier Gladys Berejiklian announced in July 2018 that “the proposed ventilation stacks are now away from schools, away from where people live”(8). Education minister Rob Stokes has said there is “no way in hell he will countenance exhaust stacks being built anywhere near a school”(3).
However the facts are that unfiltered exhaust stacks for this project will be very close to homes and schools, located:
- on Balgowlah Golf course (within 100m of homes, 300m of schools, child care facilities and aged care)
- near Kirkwood Ave, Seaforth (within 300m of homes)
- at Ernest St, Cammeray (within 100m of homes, and 300m of Anzac Park Public School).
Watch a video from Dr Ray Nassar explaining the health impacts from exposure to traffic exhaust here: https://vimeo.com/278243564
Exhaust emission dispersal
The science of exhaust emission dispersal from stacks is complex and requires detailed modelling for each precise location, a process that has been undertaken in the EIS. Marketing information from the government tells us that “the exhaust air is indistinguishable from surrounding air”, however the reality is a different story.
The figures released in the Beaches Link EIS show increased levels of pollution at various sites in the region due to the project – incorporating pollution from both exhaust stacks and surface roads. These include:
– 0.1mg/m3 (approx 3%) increase in CO 1-hour maximum
– 0.9 μg/m3 (approx 5%) increase in NO2 annual average
– 0.2 μg/m3 (approx 1%) increase in PM2.5 1-day maximum
St Cecilia’s School
– 0.25 μg/m3 (approx 1%) increase in PM2.5 1-day maximum
North Balgowlah Public School
– 3 μg/m3 (approx 2%) increase in NO2 1-hour maximum
RWR receptors (individual dwellings not identified by address)
– 0.4 mg/m3 (approx 10%) increase in CO 1-hour maximum
– 1.5 μg/m3 (approx 5%) increase in NO2 annual average
– 15 μg/m3 (approx 8%) increase in NO2 1-hour maximum
– 6.1 μg/m3 (approx 12%) increase in PM10 1-hour maximum
– 2 μg/m3 (approx 8%) increase in PM2.5 1-day maximum
Balgowlah Boys High School was not included as a community receptor for modelling, despite being within 300m and overlooking the exhaust stack.
The community are also concerned that pollution exposure figures modelled in the EIS for particulate matter (PM10 and PM2.5) are averaged over a 24-hour period. This effectively hides high exposure times (i.e. during peak hour) by averaging them with low exposure times when there is little traffic.
Whilst the increases are numerically small, they are added to already high background levels of pollution in the urban environment, and contribute to a significant reduction in air quality from the project (particularly compared to improved public transport that takes vehicles off the road). They show the increased exposure from the tunnel, new roads and exhaust stack is certainly not “indistinguishable” as described by TfNSW.
In terms of other locations that will be affected, exhaust stack function encompasses the surrounding terrain, heights of nearby buildings and all weather patterns and events. Many factors influence the ability of the concentrated emissions to disperse effectively, including air temperature, exhaust temperature, speed of exhaust expulsion, wind direction and speed.
The NSW Chief Scientist report reveals all stack designs involve increased air toxins up to a 1200m radius from an exhaust stack(4). Government documents recently leaked to the media revealed “plume downwash” is also a concern at the site(5), where additional toxins are drawn to ground level.
The diagram below shows the dispersal of concentrated emissions according to the NSW Chief Scientist report, with the red dots indicating various locations around the Balgowlah stack, including Seaforth Public School, Balgowlah Boys High, Bupa Aged Care Seaforth, Ellery Pde Seaforth and Woodbine St North Balgowlah.
NSW Chief Scientist diagram of plume dispersal
The Balgowlah exhaust stack is particularly problematic as it is located at a low point in the valley, meaning exhaust emissions will be distributed over homes and schools on the hills around it. This includes the tall apartments at Stockland Balgowlah, homes in Ellery Pde Seaforth, Woodbine St North Balgowlah, Maretimo St Balgowlah and everyone in between. Not only will thousands of residents be exposed to increased pollution levels, they will have a daily visual reminder of that fact.
The map below is from the Beaches Link EIS documents, showing the homes that are able to see the exhaust stack from their properties (Beaches Link EIS, Appendix V page 135)(10). The impacted residences are shown in purple, and also extend beyond the map shown.
The map below shows the similar impacts to homes surrounding the Seaforth exhaust stack which, due to the exhaust stack’s location on the top of a ridge, covers the far greater areas of Seaforth, North Balgowlah, Killarney Heights, Allambie Heights and Castle Cove. (Beaches Link EIS, Appendix V page 181)(11).The impacted areas are shown in pink, and are important because many residences have not been informed directly by TfNSW of impacts or community consultation.