TOOWOOMBA SECOND RANGE CROSSING Earthworks and controlled blasting Controlled blasting is a safe and precise construction methodology used to loosen hard rock that is unable to be broken up by conventional excavation methods. What’s happening? Benching To excavate the cuts (and create The cut is excavated in a series of the benches or angles), a variety of The Toowoomba Second Range steps, reducing wall height and methods may be used depending Crossing (TSRC) is being built using a maintaining stability. on the ground material and include cut-to-fill process, whereby earth is ‘cut’ graders, bulldozers, diggers and or excavated and moved to then ‘fill’ blasting. a new area or embankment which is formed by adding materials from For hard or high-strength rock, the cut. controlled blasting may be required once all other excavation methods have been exhausted. The scale of Over 16 months, approximately 10 Battering million cubic metres of earth will be the blasting depends on the daily excavated, processed and reused in The excavation face is sloped back to a progress of excavation earthworks and order to create an even surface along set angle, preventing collapse. is subject to changing weather and site the corridor. conditions. During excavation, the geological stability of the surrounding strata will be maintained by benching and battering. Scrapers removing loosened soil and rock Precision blasting Emergency access No two blasts are exactly the same: each controlled blast is Working directly with emergency services is a necessary designed to the type, strength and depth of rock remaining part of the controlled blasting process and access will be and the desired embankment slope or bench. maintained at all times. Should emergency services require access, controlled blasting activities will be put on hold until • During controlled blasting a series of small holes are there is no longer an emergency situation. drilled into the rock face and fitted with explosive charges, effectively splitting the blast into a number of smaller blasts. The charges are then released in a sequence, dispersing the impact and controlling the bench depth. • The size and the timing of the charges are selected Impact on residents based on the rock type, strength and depth and the desired benching outcome. These conditions determine Controlled blasting will have limited impacts on nearby the amount of explosive used and the subsequent residents although you may notice a momentary increase in vibration. noise, dust and vibration. • The explosive charges are released, loosening and breaking up the hard rock material. All residents in close proximity to the blast will be notified • Remnant rock and material are removed from the cut ahead of each scheduled blast. No change in your usual before the area is reassessed for the next blast. activity is required. • A controlled and precise process, the blast design is amended each time the rock formation changes. For more information please contact the Community Relations team on 1800 198 878 or email [email protected]. During construction of the TSRC, Nexus is working with specialist blasting contractors to ensure the integrity of the earthworks and minimise impacts. What does controlled blasting look and sound like? • a momentary increase in noise, dust and vibration from the blasting and associated machinery activity. Blasting itself takes only a number of seconds • changed traffic conditions. Depending on the proximity of blasting to local roads, a temporary hold and release of traffic may occur while the blast is operational • motorists may experience delays of up to five minutes during the hold and release • traffic control will be in place to safely direct motorists through the work area. Excavator moving soil within the TSRC alignment STAY IN TOUCH The Toowoomba Second Range Crossing is the largest Australian Government 1800 198 878 funding commitment to a single road project in Queensland’s history. It is a 41 km road bypass route to the north of Toowoomba. When finished, it will connect the [email protected] Warrego Highway at Helidon Spa in the east to the Gore Highway at Athol in the www.nexustsrc.com.au west via Charlton. Facebook NexusTSRC.