Environmental performance on the project was monitored constantly, particularly dust, noise and vibration.  All construction sites generate dust and noise. Strategies implemented to reduce these impacts onsite and in neighbouring areas included:

• Covering stockpiles and soil embankments with appropriate dust suppression measures
• Spraying construction sites with recycled water
• Sweeping nearby streets using a street sweeper
• Using temporary noise barriers including fencing and shipping containers
• Use of acoustic sheds
• Wheel wash downs prior to exiting site for haulage trucks or general construction traffic
• Consistent monitoring
• Where possible early land stabilisation or landscaping
• Covering of truck loads
• Organic chemical dust mitigation sprays
• Limiting cleared areas.

The air quality monitoring regime across the projects included personal and static monitoring within the worksites and external monitoring against the health based respirable limits imposed by the Coordinator- General’s Conditions for the projects. Thiess John Holland published the results of their monitoring on the Environment page of their project website during construction. 

Mitigation methods were undertaken at all sites during construction to reduce dust impacts on the surrounding community and included:

• Spraying construction sites and haulage routes with recycled water
• Sweeping nearby streets using a street sweeper
• Wheel washs and rumble grids prior to exiting site for haulage trucks or general construction traffic
• Covering of truck loads
• Spoil sheds for loading/unloading excavated materials.

The project team carried out regular noise monitoring against the Coordinator-General’s conditions at locations across the project corridor. Results of this monitoring were published monthly on the environment page of the project website.

The Department of Environment and Heritage Protection (DEHP) is the nominated compliance agency for environmental conditions set by the project.

Mitigation for noise impacts included both on-site measures such as noise barriers, enclosing tunnelling activities within acoustic sheds, limiting noisy activities to daytime hours and use of reverse “squawkers” instead of beepers on construction vehicles. Noise mitigation measures were installed at individual properties as required. This included air-conditioning or double-glazing.

Most of the major tunnelling projects here in Australia and indeed overseas must manage silica levels as they dig. Silica is the second most abundant element on earth – and if its airborne in high levels silica can be harmful.

Short-term exposure to silica in the community- such as over the life of a construction project - is very unlikely to cause anyone any long-term health problems.  The tunnelling for Airport Link was closely monitored by Workplace Health and Safety to ensure the people working to build the tunnel were protected. Controls in place at the Airport Link/Northern Busway tunnels included ventilation systems, enclosed cabins on tunnelling machinery, dust suppression systems, and personal protective equipment.

Onsite monitoring results were reviewed by the projects’ tunnel management teams in conjunction with other controls in place, discussed with area safety committees and the workforce, and posted on site noticeboards. All external air quality monitoring results were published on the project website in the monthly Environmental Monitoring Report.