7.0 Objection to the impact on air quality and EIS assessment of impact

WAG objects to both the impact WestConnex, including the New M5, will have on Sydney’s air quality, and the failure of this EIS to properly assess those impacts.

The air quality assessment in this EIS relies too heavily on the WestConnex Road Traffic Model (WRTM) forecast.

In what should have been an independent study, the air quality assessment needed to model a fuller range of traffic scenarios for the corridor, including possible “rat runs” used to avoid tolls and thus changing the air quality at those points.

The fact that the project corridor has numerous traffic “hot spots”, where levels of dangerous pollutants are already elevated, is glossed over, and the dangers of adding to these “hot spots” and creating more of them is not taken into account by the overly conservative induced traffic forecasts.

There has been no comparison between the project and other cleaner forms of transport.

The air quality assessment makes no mention of the possibility of phasing out diesel fuel passenger vehicles as one way of assisting with the problem of elevated levels of PM2.5 and NO2 in the corridor.

The air quality assessment also fails to comply with the project SEARS in a number of instances, as well as failing to provide enough data to adequately assess compliance with some SEARS. 

Particle pollution levels along the proposed WestConnex route are already at or above current standards, and well above proposed standards. This is also true of coarse particle (PM10) pollution levels.

Particle pollution levels near the proposed project already exceed the current PM10 and PM2.5 standards. Construction and operation of WestConnex will increase pollution concentrations and adverse health impacts. 

Rather than building more mega-toll road projects like WestConnex that will only add to these levels, the NSW Government should be acting to prevent any additional sources of fine particle pollution and to actively manage existing polluters.

In 2014, the OECD published a study showing that  of 34 countries in the OECD, 20 saw their pollution-related deaths decline in that five-year period. Australia was in the minority of 14 countries that saw their death rates increase. As mentioned in section 6.1 of this submission, Professor Paul Torzillo explained at a WAG public meeting in Newtown that health risks do increase for those living near congested road. The EIS for the New M5 reveals that in St Peters, Alexandria and Kinggrove hundreds of residents are already exposed to high levels of Fine Particle Pollution 2,5. and will be exposed to higher levels.

7.1 Flaws in the methodology of the EIS report

●     The air quality assessment relies upon the validity of the traffic modelling assessment. If the traffic modelling assessment has under estimated traffic volumes or has incorrectly characterised traffic volumes, it is possible that the air pollutant levels may also have been incorrectly characterised. As outlined in Section 4.0 of this submission, it is very likely that the traffic forecasts in this EIS are incorrect, which would render this air quality assessment incorrect as well.

●     The estimates for “induced demand” in traffic are very conservative, given they rely on population forecasts which may underestimate population growth along the corridor.

●     Data reported against the current standard of 25ug/m3 (24-hour average) does not give an accurate picture of the peak hour traffic emissions, which would be well above the standard; the fact that children are walking to school near several of these sites in the morning peak hour means they are being daily exposed to dangerous emission levels. If their classrooms are also located near the sites with elevated emissions, they are exposed for lengthy periods.

●     The community receptors used to indicate changes to emission levels at 2021 and 2031 already show levels of PM2.5 are above the new NEPM standard. If the WestConnex project induces more traffic to the area by 2031 (or the population grows faster than planned or more diesel vehicles use the road or tunnel) then PM2.5 levels will be well over the current standard, let alone the new standard.

●     The planned height of the ventilation stacks is not modelled to show other scenarios, including effects of greater heights on dispersal of pollutants; there is a lot of international research that indicates a greater height of stack results in better dispersion.

●     The air quality assessment seems to downplay the key findings from the Human Health Risk Assessment.

●     The claim there will be no emissions from portal sites is highly questionable, given that any congestion on the feeder road into a portal entrance or the exit point will produce concentrated sites of emissions

●     The GRAL dispersion model has been adopted in the air quality assessment for surface roads and for the ventilation outlet. The GRAL model was designed principally to model emissions from surface roads and tunnel portals in complex urban environments. Whilst the model has the capability to model emissions from ventilation outlets, other models such as CALPUFF are more often used. The GRAL model has certain limitations relative to CALPUFF, for example in relation to the characterisation of the temperature of the plume.

●     Insufficient information has been provided to enable a detailed review of the model inputs.

●     The air quality assessment has not predicted concentrations of air pollutants on elevated receptors. Experience elsewhere shows that higher concentrations of air pollutants will be experienced by receptors that are elevated above the ground when emissions occur from an elevated emission source. For example, the upper floors of a multi-storey building may receive higher concentrations of air pollutants from a stack or vent than are experienced at ground level. No justification is provided for this omission, which is particularly significant given the number of multi-storey buildings that already exist in the area, and the high number of medium-to-high rise developments planned. Consequently, the air quality assessment may have under-predicted concentrations of air pollutants on the upper floors of multi-storey apartments. The air quality assessment makes no mention of any plans to re-assess concentrations of air pollutants on the facades of any existing or possible future multi-storey buildings in the vicinity of the ventilation stacks.

●     The air quality assessment has not quantified emissions or ground-level concentrations of all air pollutants that may be associated with motor vehicles. For example, metals associated with the project. WAG notes that the NSW EPA’s 2008 Air Emissions Inventory for the Greater Metropolitan Region in New South Wales includes a range of metals from motor vehicles. There are a range of other air pollutants that are emitted from motor vehicles including metals, sulphur dioxide and volatile organic compounds. While these excluded air pollutants will not be critical in an assessment against air quality criteria, they may be an important consideration in the human health risk assessment, which relies on this air quality assessment.

●     The air quality assessment has provided data only for the averaging times that are relevant for the regulatory assessment against air quality criteria. However, model predictions of short-term periods is required for the Human Health Risk Assessment (HHRA) in this EIS. This omission seriously compromises both the air quality assessment and HHRA in this report, both of which are critical to the overall validity (or lack thereof) of this entire EIS.

●     The air pollutant emission rates applied in the dispersion model appear to have been averaged through each day. If this is correct, peak 1-hour average ground-level concentrations of air pollutants are likely to have been underestimated. This will have implications for the regulatory assessment of nitrogen dioxide and other air pollutants that have criteria averaged over 1 hour. This will also have implications for the Human Health Risk Assessment.

●     The air quality assessment has not provided predicted ground-level concentrations of air pollutants due to the ventilation outlets in isolation of the surface roads and regional background levels of air pollutants. This information is relevant to understanding the potential impacts of the project, whether filtration of ventilated air is required and its potential benefit.

●     There is a lack of a quantitative assessment of air quality impacts from the construction phase of the project. The New M5 EIS has adopted a semi-quantitative approach to assess construction impacts on air quality. The air quality assessment has not quantitatively assessed emissions and potential impacts of air pollutants from the project during construction. WAG does not consider it acceptable that such a significant risk to residents’ and workers’ health and safety risks being compromised by the proponent’s failure to assess this as part of the EIS.

●     There is a lack of information in the air quality assessment regarding monitoring (both ambient and in-tunnel) during the operation of the New M5 Project.

●     While the air quality assessment makes some attempt to identify the pollutant exposure for the New M5 journey (even though this is not complete when it comes to factors such as the types of pollutants measured), no attempt is made to measure either the levels or impact of cumulative exposure for people who would remain in tunnels for longer journeys if the remaining WestConnex tunnels are built, or for journeys that would include other existing or planned road tunnels.

7.2 Flaws in model’s assumptions

The benefits from the project, in terms of some reduced pollutant concentrations at particular points depend on completion of stage 3 of WestConnex and other unplanned toll road projects, which may not eventuate if tolling of stage 1 and this project do not meet estimated revenue. If stage 3 is not completed, the levels of PM2.5 throughout many parts of the route will exceed current advisory and new standards.

The overall benefits rely on the WRTM traffic model being accurate. Traffic forecasting is a major issue in Australia, given the number of projects with significantly incorrect forecasts of volume, including the Brisbane N-S By-Pass, Sydney Cross City Tunnel, Brisbane Connections, Lane Cove Tunnel and East-Link Melbourne. As the Australian Bureau of Transport and Communication Economics, Canberra states, traffic models are … “radical simplifications of real urban systems” (cited in Black, J (2014) Traffic Risk in the Australian Toll Road Sector, Public Infrastructure Bulletin, Vol 1, Issue 9, Art 3). So all the claims of improvements in overall air quality, or at best negligible impacts on air quality, are reliant on the accuracy of the traffic modelling.

As Black (ib id, p5) shows, the eight most recently built toll-roads in Australia have all had significant underestimation of traffic volumes by an average ratio of .48 (total traffic from the 8 projects forecast as 945,286 vehicles, but actual volume was 455,939 vehicles). The proponent must be very optimistic that this project will be the first one in many years to get the traffic forecasts correct. The problem is that local residents’ lives are about to be severely interrupted and possibly have the air quality worsened if this project attracts more traffic than estimated onto the surface roads.

Following a review of local and international reports and data, the Australian Department of Infrastructure and Transport, Bureau of Transport and Regional Economics (BITRE) in its Review of Traffic Forecasting Performance Toll Roads (2011) sets out what it sees as the major sources of errors in toll road forecasting. These errors include both technical (inadequate models, data limitations, unrealistic model input assumptions and ramp-up risk) and non-technical (optimism bias and strategic misrepresentation) sources of errors. The robustness of the WRTM model is crucial to the claims that the air quality will not be adversely affected by the project, and this air quality assessment should have included a worst-case scenario of more than projected traffic, particularly given the series flaws in this EIS’s traffic modelling as detailed elsewhere in this submission.

The air quality assessment appears to ignore key actions recommended in the new National Clean Air Act, including initiatives to reduce localised emissions. The WestConnex project will not only increase levels of NO2 and PM2.5 at several community receptors, it also runs the risk (if estimated traffic flows are greater than predicted) of increasing these levels across the Corridor. This project will not be futureproofing Sydney.

Even if we accept the assertion in the EIS that the exhaust ventilation tunnel will for the most part allow for reasonable distribution of pollutants away from the immediate vicinity (which WAG does not), several issues of concern remain. For example, what would be the impact of intense localised plume strikes onto small areas, which will cause often short, but quite intense concentrations of pollutants in a restricted area, due to changes in wind patterns or atmospheric inversion layers? These acute events can be a major trigger for acute asthma episodes or people with other chronic lung conditions.

With regard to in-tunnel air quality monitoring, the air quality assessment states the ventilation system would be automatically controlled using real-time traffic data covering both traffic mix and speed, and feedback from air quality sensors in the tunnel, to ensure in-tunnel conditions are managed effectively in accordance with the agreed criteria. The air quality assessment does not specify the pollutants to be monitored, the method of monitoring, nor the location. This is a disturbing omission given that so much of WestConnex, including this New M5, is made of tunnels that drivers may end up spending extended periods of time in.

The proponents allege that WestConnex will improve air quality. This beggars belief. Building and expanding motorways increases air pollution, as motorways induce traffic. 

The EIS assumes an increase in vehicle kilometres travelled (VKT) in the WestConnex domain. Increasing road capacity will directly increase VKT. As a result, air pollution worsens.

Across Sydney, ambient concentrations of PM2.5 and PM10 are increasing. This compels the NSW Government to act to improve air quality and take all available measures to reduce particle emissions.

The prediction that constructing WestConnex can reduce emissions is based in part on the assumption that the motorway will ensure that traffic moves faster and more freely. In reality, many motorways become congested more rapidly than expected, due in part to induced traffic.

7.3 Conclusion 

WAG formally and strongly objects to both the air quality impacts of the WestConnex including the New M5, and to the way in which this air quality assessment has been conducted. We ask the Minister for Planning to reject the WestConnex New M5 project.


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