Brilliant day at the Kemi Mine… Had a good presentation about what they do and how they do it, then we had a look at the biggest of the (now unused) open mines. It was 800m across and very deep… But it is no longer used because they are now in the underground mine where the reserves are easier to get at.
We drove down in a minibus all the way down to level 600 (600 meters down into the center of the planet). There is not a great lot to see there, only a water pump and the bottom of the hoist (the lift). They pump water from there which has come down from higher levels - water is used to cool and clean the machines and plant, and used a lot in the drilling, so they have to get it out somehow.
We learned that there is a rowing boat on level 300 (or 320, I can’t remember), because in the initial stages when they first were opening up the mine (a lot of years ago), that level flooded and they could use their hands on the roof to push them along because it was so full - I think Jans said a pump had broken… Yeah, I think it did :-) But there was no sign of that happening again… Thank goodness!
On level 500, there is a big maintenance shop and a load of offices. It really looked like a normal office but with no windows, you wouldn’t think you were half a kilometre of rock and stuff above your head…! It was so clean and bright, the walls had been white washed, there was even a canteen which had been done really neatly.
We also visited the crusher and the conveyor belts that transport the rock to the upper levels, I had seen it before, but the size of it is amazing! You can feel that it is very powerful. It was not running this time, but I already have photos of it on Facebook (under my INTRO album).
We managed to even see the Production Levels which I was very grateful for, the bread and butter of what the mine is about, getting Ore out of the ground. We saw them drilling and fitting the supporting rods into the ground… 2.5m rods of steel that a drilled into the rock and then injected with water to force the end to expand (a lot of water is used), it holds the rock up long enough for them to mine each section.
It was good to learn that they backfill each section, so they only have to support it for as long as they are mining that section, it also means that some of the air which is pumped down from the surface is not wasted in unused sections of the mine.
Once we’d done at the lower levels, we made the 500m climb in the minibus and said goodbye to our tour guide (after we’d had some lunch).
As I was walking around, I noticed how reliant they are on the wireless network, everyone has a VoIP phone connected to the network, which they can used to locate each person in the mine - as long as they are carrying it with them - this is used for safety and is useful when someone is late to your meeting and you want to know where they are! For safety, they can make sure that everyone is cleared out of the mine (or is hiding out at Level 500) when they are blasting - twice a day at 2pm and 10pm… They also have some really good Process Control systems which is managed from the surface by the engineers, watching over all their machines!!! The rest of the day was just doing my day-to-day work… Which was nowhere near as cool as the mine :-)