Close up of Tui Mine

View from the Tui Mine site, looking out over the town of Te Aroha and the Hauraki Plains

 As part of the research I'm doing for my next mining project I visited the site of the Tui Mine with some friends this week.  As it is the most toxic site in New Zealand and currently being remediated, there is no vehicle access, and many dire warnings about accessing it on foot.  So we didn't know how close we could get until we got there.  The walk up Te Aroha mountain was very steep, through some very beautiful native bush. There were a few birds about, but not many- which is not unusual for the middle of the day.  

Tunakohia  Stream, fed with water from inside the mines

We crossed several sparkling clear streams and rills, but despite the temptations of the beautiful water we tried to avoid contact with it, sharing our water bottles with Tara the dog so she wouldn't drink from the streams.  After heavy rains, or when the mine site is disturbed (as it must be during the remediation work), these streams can be full of toxic heavy metals (lead, cadium, mercury).   

Some rusty old mining rubbish lying around in the bush

 As we got higher up the mountainside and closer to the mine site, we started to hear the roar of heavy machinery and even a muffled explosion. The lower level of the large area of the mine is the tailings dam which is the current focus of remediation work.   I managed to get a peep at it through the trees, but could only see a small section of new tailings dam under construction. It will replace the crumbling old concrete dam left by the mining company when they flitted off leaving 90,000 tonnes of toxic tailings perched precariously on the steep mountainside above the little town of Te Aroha.

Constructing the new tailings dam

Higher and higher we climbed, and eventually came to one of the entrances to the underground mines of Tui. I thought recognised it from an old home video I watched at Te Aroha museum last months where a group of ex-miners revisit their old work place. This meant I could visualise the inside of the mine (dark, wet, dangerous, deep), even though the entrance is decisively blocked (not that I would venture inside a Tui Mine casually anyway).

Entrance to underground mine (top right).  Tunakohoia stream flows right past (see it coming out of the bush just above the dog?)

The mine was abandoned 30 years ago and although the lush bush crowds up the edges of the site, nothing can grow on the cleared ground, so toxic is the earth.  Looking at it, it feels very raw and new, but after thirty years, anywhere else would have overgrown the stream with vegetation.

Mine entrance, with water flowing out with bright orange sediment 

The mine's water runs straight down the blasted cliff face to join the Tunakohoia Stream

Looking down from the mine entrance

I was very excited to be able to be right there, on the mine site, seeing with my own eyes the details and the context.  I was particularly looking at the colours, because that is the decision making I'm immersed in at the moment with my mining project.   I didn't see anything that looked like cinnabar, though the dark red lichen growing on many rocks is a similar colour. 

The only life in the mine clearing are a few kinds of unfamiliiar lichens, presumably the kind that flourish on a diet of heavy metals.

We did find this piece of quartz stained with the same bright orange that flows out of the mine. I don't know exactly what the orange stuff is, but everything I've read about Tui suggests its a highly toxic mineral. 

Tui Quartz

When NORPAC abandoned Tui so abruptly after the market for their dangerous product disappeared, they left a lot behind.  A hundred tonnes or so of ore apparently, and the tailings of course.  But the most visible/accessible stuff these days are all the bits of rusting kit and a few concrete foundations. 

After we walked back down the steep mountainside, we drove to the otherside of Te Aroha town, to the charming historic Domain with its multitude of mineral spas. A luxurious soak in a warm outdoor pool was just what our sore feet and tired legs needed.  When my fingers and toes were pale and wrinkled I finally felt cleansed of any contact with Tui's toxic legacy.