North-South Corridor - Torrens to Darlington (T2D) environmental regulation
The Torrens to Darlington (T2D) road project is the final 10.5 km section of the North-South Corridor, and is the most significant road infrastructure project ever undertaken by the South Australian Department for Infrastructure and Transport (DIT). Using a combination of tunnels, a lowered and surface-level motorway, and overpasses and underpasses at key intersections, the T2D project will complete 78 km of non-stop traffic-light free motorway between Gawler and Old Noarlunga.
The Environment Protection Authority (EPA) regulates industry and government agencies for activities impacting on the environment, creating a better environment for the health, wellbeing, and prosperity of all South Australians.
Given the range of environmental aspects associated with the T2D project, the EPA will play a significant role in providing timely and effective advice to DIT, the community, and other stakeholders, as well as ensuring requirements of the Environment Protection Act 1993 (EP Act) and associated legislation are met. Areas of relevant legislation applicable to the project include:
- Air quality
- Noise and vibration
- Soil disposal, waste and recycling
- Water quality.
For more information about the T2D project, please contact the T2D alliance:
Website – t2d.sa.gov.au
Phone – 1300 951 145
Email – info@T2Dalliance.com.au
For further information about the EPA's involvement in the project, please email engage.epa@sa.gov.au.
Air quality and dust
The EPA is considering potential air quality impacts from activities that occur before, during, and after road construction. There is substantial evidence that air pollution has adverse effects on our health and consequently any improvement in air quality will result in improved health outcomes.
Air quality after construction is being considered at the design stage, so that traffic and emissions modelling informs the design, and reasonable and practicable measures are taken to prevent or minimise any adverse air quality impacts. This includes ventilation requirements within the tunnels and the safe discharge of tunnel-ventilation emissions.
Section 25 of the EP Act requires DIT and its contractors to implement all reasonable and practicable measures to minimise any impact on air quality during demolition and construction activities. This includes dust suppression, consideration of meteorological conditions for certain earth-moving activities, and implementation of all necessary controls to manage dust.
All work needs to meet the legislative criteria specified in the Environment Protection (Air Quality) Policy 2016 and the General Environmental Duty requirements in section 25 of the EP Act.
Noise and vibration
There are noise and vibration mitigation requirements associated with the T2D project, during both construction and operation when the project is complete.
Noise and vibration during construction and operation of the proposed road and tunnels must comply with the EP Act. In order to comply with section 25 of the EP Act, DIT must undertake design and construction work according to its Guideline for the Management of Noise and Vibration: Construction and Maintenance Activities. DIT must also consider its Road Traffic Noise Guidelines.
DIT and its contractors must consider and address the potential effects of construction and maintenance noise and vibration during the planning phase, and undertake reasonable and practicable mitigation to avoid nuisance to the community and the environment. DIT's noise and vibration webpage outlines its approach to management and mitigation.
Waste management
The EP Act and Environment Protection (Waste to Resources) Policy 2010 define 'waste' and set out the regulatory requirements for waste management activities. One of these requirements is the implementation of the waste management hierarchy, which prioritises various waste management approaches.
In accordance with the hierarchy, avoiding waste generation is most preferred, while disposal should only occur when other waste management options such as reuse are not possible. In applying the waste management hierarchy and protecting the environment, the EPA seeks to:
- Promote the best and safest use of recovered resources
- Reduce the amount of waste going to landfill and ending up in our environment.
A circular economy is a self-sustaining system which aims to keep materials in use, or ‘circulating’, for as long as possible. It extracts the maximum value from materials such as soils while in use, then recovers and reuses them in other forms. There will be a need to manage excess soil that is generated from the tunnel boring machine process and the excavation required for the lowered motorways and tunnel portals. An example of reuse is the use of the material as fill in accordance with the EPA’s Standard for the production and use of waste derived fill.
DIT has been undertaking testing of relevant geotechnical, hydrogeological, and contamination conditions close to South Road. This program is ongoing and will assist in determining the most appropriate waste soil management options during construction.
Transportation of soil generated by the tunnel boring machines and excavation will also be an important consideration. In accordance with the Environment Protection (Waste to Resources) Policy 2010, a person who transports waste, including waste soil and construction and demolition waste, must take all reasonable and practicable steps to cover, contain, or secure the waste. Depending on the waste that is being transported, an EPA Licence may be required and the waste must be tracked.
Water quality – surface water, stormwater and groundwater
The EPA is responsible for responding to water pollution through the EP Act and the Environment Protection (Water Quality) Policy 2015. The EP Act and Water Quality Policy place a general obligation on DIT and its contractors to take all reasonable and practicable measures to minimise environmental harm caused by pollution.
The Water Quality Policy states that a person must not discharge pollutants into any waters. The definition of waters includes public stormwater systems, groundwaters, inland surface waters, and marine waters. Listed pollutants cannot be placed into any of these waters or onto land in a place where they are reasonably likely to enter these waters.
The EPA is providing guidance to DIT and the T2D Alliance in relation to the appropriate management of various aspects of the project relating to water quality. Some activities associated with the management of surface water, stormwater, and groundwater will require an EPA licence.