Morwell Land Movement - Princes Freeway Closure Community Update
Monday, 27 June 2011
Incident history
A major rain event in early February caused a large amount of water to enter the Morwell Main Drain inside the boundary of Hazelwood’s coal mine. This caused some land movement and cracking which affected the Princes Freeway. The Princes Freeway was closed at Morwell in both directions and traffic is being diverted through the Morwell township. The emergency management team (EMT), made up of key agencies and stakeholders and headed by Incident Controller Superintendent Tess Walsh, is working to ensure the safety of the area.
Update
There has been no significant ground movement in recent weeks. Forty six bore holes have now been drilled and completed. A further 13 bore holes up to 1000m long will be drilled at the base of the mine wall adjacent to existing boreholes. Recent monitoring shows some decreases in ground water levels as a result of the bore holes draining water away from the area.
FAQs
● Has the design work been completed for an improved drainage system?
The drain design work has been submitted by Hazelwood and is being finalised now in conjunction with DPI. It is expected that this will be completed in the coming weeks.
● When will this work be completed and when will the road be re-opened?
The Quantitative Risk Assessment and the drain design are both expected to be completed in the coming weeks. Information will then be available to develop and communicate a plan for the completion of the works. This will inform decisions on the re-opening of the road.
● Why hasn’t the mine been back-filled?
The overlaying material (overburden) on the coal in Hazelwood mine is up to 15 metres thick, while the coal seam is up to 100 metres thick. There is not enough material to replace the volume removed in the past 55 years. However, the mine has been 'backfilling' overburden into the mine in recent years to provide dust suppression and add weight to both the mine floor and the older mine slopes.
● There seems to be an increased number of trucks travelling through town. Are these over dimensional vehicles? Are they able to travel along the detour route?
Vehicles can be over dimensional by the nature of the load they carry or by the special purpose they perform. Large trucks such as B-doubles are not over dimensional vehicles. Some over dimensional vehicles have limited access to the road network because of their size or their mass and require a permit to travel. However smaller over dimensional vehicles do not require a permit to travel on our roads and are entitled to use the Morwell detour. Those carrying larger loads, which do require a permit, must use the designated route OD 9.
Communication
For more information please visit: http://www.police.vic.gov.au
Updates will also be sent out via the Department of Justice’s Twitter feed: twitter.com/justice_vic