Sinkhole found alongside mine in Waihi

Wednesday, 30 August 2017

A sinkhole has been discovered alongside an open pit mine in Waihi.

A sinkhole 20 metres-wide has been discovered in the Coromandel mining town of Waihi.

Hauraki District Council discovered the hole on piece of council reserve land adjacent to the Martha open pit mine on Tuesday morning.

A 20m-wide sinkhole has been found in Waihi.

The area was a high hazard zone, and the site of historic mine workings, chief executive Langley Cavers said.

'While this is inconvenient, it is within an area where potential sinkholes could be expected.'

The sinkhole is the result of partially filled old mining works collapsing.

**READ MORE:

* What is a sinkhole?

A mine shaft collapsed in Waihi in 2001, starting a process of reassessing the risk of collapse around the city.

* New Waihi sinkhole mystery**

The sinkhole collapsed into the top 20 metres of an old mine that was left partially-filled.

It was discovered after the collapse took out power to a number of nearby pensioner flats.

Council staff have visited the residents and there was no ongoing safety concerns.

It is the largest mine collapse since December 2001, when a hole swallowed a house, a van and two cars on Seddon St.

Seddon St formerly passed over the discovered sinkhole, but was shifted after the collapse risk to the city was assessed in 2002.

A 2002 report determined 174 Waihi properties were in high, medium or low risk areas because of potential mine collapses. Sixty four properties were marked to be vacated.

The owner of the adjacent mine, Oceana Gold, was helping to fill the hole on Wednesday.

Community advisor Kit Wilson said it made sense for the company to provide the material to fill the hole.

'The sinkhole is 50 metres from the mine, the material is 50 metres away, and we've got trucks and diggers.'