Ipswich Motorway Upgrade, Dinmore to Goodna: Remediation of Abandoned Coalmines

Barry Land & Bill Holz

At $2bn the Ipswich Motorway, D2G Upgrade southwest of Brisbane is the largest federally funded project in QLD. The 8km section of road, Queensland’s busiest, crosses three abandoned coal mines worked at various times between the late 1800s and the 1980s.

Following investigation and analysis of the stability of each of the mines the decision was taken to fill them to ensure long term stability and safety for the road using public, the works being carried out on a sub-alliance basis to the main alliance. Each mine provided differing scenarios of geometry, depth, documentation and groundwater/methane filled mine void. Remediation procedures were developed and implemented for each mine. The D2G project is the largest abandoned mine infilling project to have taken place in Australia and provided a number of challenges and innovative solutions, including:

• Investigation of non-documented mine workings
• Stability analysis and assessment
• Groundwater Management
• Methane Management
• Target drilling
• Mapping through the use of down hole cameras.
• Sub-alliance delivery to provide value for money

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