Thursday, January 21, 2010

Touring a Park City mine tunnel

This afternoon I got to take a tour that very few people get to do.

Park City sprung to life back in the late 1800's when silver was discovered. It's rich with mining history. You can wander around the town and local mountains to see 100 year old mine entrances, smelters, oar bins and much more.

There are hundreds of miles of mine tunnels running every which way under Park City. One of the problems the miners had was trying to drain the water out of their tunnels. They built huge pumps, but the pumps just couldn't keep up with Mother Nature. The mining companies finally started building drain tunnels to haul the water down to lower elevations.

I got to go travel through the Keetly Drain tunnel, which runs from the Jordanelle Reservoir to a spot deep under the Deer Valley ski resort.

I expected a modern mine to look like the picture above. That was only the first few feet. The rest of it looked more like the picture below.

Notice the narrow gauge rail tracks on the floor. Turns out it isn't the floor. Each support structure looks like a squared-off capital "A". The track is actually running on the crossbar of the "A". Underneath it is about 4 feet of water. The trains made a little wake as they cruised along and you had to keep your feet on a timber because water ran through the cars.

This was our train. We road in the little red wagons. They were pulled (or pushed) by a little diesel engine. It wasn't a short trip. We ventured 15,000 feet into the tunnel, almost three miles. When we stopped, we were almost 1,500 feet beneath the surface. They gave us a lecture about keeping our hands and heads inside the train cars. They meant it. At times, the tunnel got small enough that carelessness could easily result in injury.

This was one of our miner/tour guides. He has worked in mines for many, many years.

There is still a lot of very old mining equipment in rooms off the tunnels. This was an air compressor. It allowed the miners to switch from drilling holes in the rock by hand, to using early versions of air hammers.

To get huge pieces of machinery into the mine, they would cut the equipment into pieces and then put it back together when it got to its destination. They even did this with a large flywheel, which really shouldn't be possible. The miners were incredible engineers.

There were only a few places, mostly bigger rooms, where they really had to reinforce the ceiling. It almost looked like the early 70s computer-generated art.

I had never heard of a flat steel cable, but that's what they used for the lift to the surface. It was about five inches wide, but not very thick. That gave it the strength it needed, but it spooled up a lot tighter on the big wheel. I guess that's a concern when you are spooling 1000+ feet.

While I am sure most of the jobs in the mine required focus, the hoist operator was one of the most important. He sat in this little booth and no one was allowed to talk to him while he was working. The pisser is that the hoist is in another room and the operator can't even see it. It is all done by sound and signals.

There is a pedal on the floor that acts as a dead man's switch. If he dies or leaves, at least the hoist doesn't keep running forever.

We ran through different seams of rock as we traveled our three miles. Some areas were hard and didn't require any support. Others were soft and likely to shift occasionally. There was even a chunk of volcanic rock from 35 million years ago. Probably the same damn volcano that created the ash we had to dig out of our foundation.

I liked the vein of green rock. Can't imagine it is anything special though. Some of us were disappointed to find out that there aren't any silver veins or nuggets. If you found some rich ore, it would have 20 ounces of silver in a ton of ore. That's a lot of blasting, digging, hauling and smelting for so little.

Deep into the tunnel we came into a work room. It seemed like they had stuff to fix most anything.

They had drilled and marked a demo blast. We got some education on how the blast is set up and timed so that it mostly blasts in place. You don't want it to blow out all over the place.

The normal routine was to finish your shift with a blast. The next crew would haul out the ore, set the next blast, blow it, then head home. Shift after shirt after shift.

For every miner working in a tunnel, there would often be three or four other workers. They did all sorts of different jobs but quite a few of them involved caring for the horses that were down in the tunnels. I've heard of bad jobs, but how would you like to work deep in the mountain, in a dark, wet drainage tunnel, picking up the poop from the horses?

Alison Pierce is a fellow Wednesday Host over at PCMR. She's wearing the every so stylish plastic poncho and miner's helmet. This was one of the many warning signs we saw.

This one wasn't as clear about the problem, but you got the point.

A more subtle warning.

The biggest concern for the miners was fire. The flames weren't the big fear. It was the fire's consumption of all the oxygen. There were large metal doors along the tunnels that could be closed to shut off the air flow.

This was one of my favorite sights. When a fire broke out in the mine, you wanted to let the other miners know. The problem is that there wasn't any easy way to communicate through miles of tunnel. They used a combination of the natural air flow through the tunnel with a stink bomb. The "stench bottle" contained a chemical that smelled like rotten eggs. It's the same idea they use so you can smell propane leaks. The smell would float through the tunnel and everyone would know something was wrong.

They are lucky with the natural air flow in this tunnel. In the winter, it flows from the mouth of the tunnel to the top of the shaft. In the summer it flows the other direction. This keeps them from having to do a lot of mechanical ventilation.

A big thanks to Ian Patrick and Stephen Long for making this visit possible. It is great to get to see a bit of what really created the town of Park City.
Post a Comment