Subsidence Advisory NSW Acknowledge Mine Workings Privately

38 Maitland Road was abandoned by us in 2014 due to subsidence issues and flooding. We tried to get support from a variety of government agencies including Subsidence Advisory (Mine Subsidence Board), Newcastle City Council, Hunter Water, and more… All could not explain why the buildings were cracking and why we had water flowing into the buildings.

In 2015, we try to sell 38 Maitland Road Mayfield, and allow a developer to handle their own investigation where they hired independent geotechnical engineers. These included RCA Australia, Northrop Engineers and Cardno (Stantec).

As part of the analysis, the Cardno/RCA conducted lengthy geotechnical investigations including borehole testing and concluded that it is most likely the borehole coal seam and mine workings are approximately 7m below EGL from the building at the front of the site. An updated mine workings map was created and shared with SA NSW.

In 2015, David Sedgman (acting District Manager) from SA NSW is discussing the development application with our 3rd party buyer. His first paragraph to the proposed buyer is;

ENQUIRY NO: TENQ15-13682N1
LOT 1 DP 782225 SEC NO 38 MAITLAND RD MAYFIELD

This property is located within a proclaimed Mine Subsidence District. The purpose of a District is to prevent damage through surface development controls that take account of the risk of damage by subsidence from old, current and future mining.

In Feb 2016, Ian Bullen (District Manager) from SA NSW continues discussions with the 3^rd party buyer;

“I have had a look at the geotechnical report as well as Northrop Engineers comments, the use of bored piers would need to be assessed on merit when you submit your DA drawings, it will be the decision of the Board as to weather they believe that bored piers will address the issues with shallow mining and the long term stability of the structure.”

“Due to the extremely shallow depth of the workings the Board would not be able to confirm or comment that the workings will or will not collapse causing damage to the infrastructure and or injury to the public. This is something that your Geotechnical consultant would need to comment on, if the Geotechnical consultant believes the risk is high then they need to specify a suitable method such as grouting to make the workings safe.”

Note:     Ian Bullen was the SA NSW representative that met with us on site in 2012 and 2015 stating that there were no mine workings on our properties.

After a long process, the developer walked away from the property, remediation costs with the ongoing water problem making this property unmanageable.

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2002, Mines under our building as discussed with engineer (GIPA)
2012, No mines under our buildings as told to us by SA NSW
2015, No mines under our buildings as told to us by SA NSW
2015, Mines under our building as per David Sedgman SA NSW (GIPA)
2016, Mines under our buildings as per Ian Bullen SA NSW (GIPA)