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flintgreasewood

Life At The Bottom Of A 64' Shaft

17 posts in this topic

Late December last year I began digging a 6' x 6' prospect shaft about 100' downstream from the original Cobb prospect shaft. Armed with a 30 lb electric jack hammer, a couple of shovels and my nifty 1/2 size home made "Fairbanks self dumping bucket" system I worked my way down through frozen muck and eventually a 10' gravel layer to bed rock at 62'. On my way down I encountered layers of tangled branches and trees up to 6" in diameter. After 40+ feet I hit fine sand and scattered patches of gravel, fossil bone fragments, then complete bones. I was anticipating these finds but the excitement of actually finding them was intense. The first chunk of mammoth tusk nearly put me over the top. Progressing downward, the bones became less frequent and the pay gravel more dense. I had been told that a jack hammer would be ineffective in frozen gravel. Good I don't listen to everything I hear; it busted up almost as easy as the muck. The gravel graded into fractured and decomposed bed rock and I knew I had finally reached my goal...10 months after starting the project. Before freeze up I was able to wash 5 yards of pay and the result was encouraging. I'll have to wait till late spring to resume processing what I brought up before and what I can hoist this winter.

Now it's late November and all is solidly frozen above as well as below ground. Since bottoming out in the shaft I've been devoting most of my time to upgrades above the shaft in preparation for winter work. Also I had to take a part time job in town to help pay for the added expense of moving to a small cabin also in Fairbanks. What little time I've been able to devote to underground efforts have been to expand my working space. On the way down I managed to increase the dimensions of the shaft from 6' x 6' to over 7' square. The plan is to continue out to 10' square before I begin pushing the drifts across the valley.

Jack hammering straight down is relatively easy compared to working horizontally and even vertically. Sufficient pressure is difficult to exert out of position so I began working on ideas to free the gravel other than by the traditional steaming or blasting to reduce the great amount of physical labor involved with jack hammering. Suffice it to say, I'm making good progress in those efforts. I'll report on this process in months to come.

Ronald C and dredgernaut like this

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Thanks, Doug I hope my efforts serve as an encouragement to other current and future drift miners. I'm hoping to develop simple systems that can be utilized by even just one person to successfully mine underground.

B O'Berry likes this

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Kurt.....glad to hear you finally got to the bottom of that thing!  I was wondering how you are going to protect the shaft from filling up during the winter?  I realize it will be inevitable that you will get moisture inside but what type of steps will you take to minimize it so that you can hit the ground running again in the spring?   

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JR, Good to hear back from you. The seepage into the shaft ended shortly after freeze up. All is nice and dry down below. I'll be digging a substantial trench up stream this spring to hopefully divert any flow into the shaft next summer. Let's hope it works.

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I'm sure its all socked in with snow now, but I hope the melt doesnt create problems.

Assuming its not much work to re-open this coming spring, will you start drifting out horizontally?

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Hi Chris

It's almost February and I'll soon be starting my cross valley drifts.  In anticipation of increased material removal I am beefing up and enlarging my hoisting system. Should be an exciting season. Good luck to you

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Good luck to you!

I'm looking forward to hearing more about your progress. I hope you hit a nice rich paystreak.

Still a bit cold here for detecting in Northern Nevada / Northern California, but it wont be too many weeks until I am out there digging.

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Kurt, I want to see what the gravels look like that you will be pulling out of that thing.  From the blog that you have posted, I envision you down on ancient riverbed approaching bedrock?  You've mentioned you got to the gravels, but have you also discovered how far down bedrock is under the gravels? 

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Hey guys

   I have approximately 10 feet of gravel on top of bed rock.  I'm only beginning to run my drifts across valley so I'm not able to say what the angle of bed rock is yet.  Now I'm recovering from back surgery [relatively minor] but it's going to keep me from any vigorous mine work for several weeks.  Ahhh, patience!

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I can certainly relate to the back pain thing - sorry you had to have surgery. No surgery for me as mine is not that bad but I know it can certainly slow you down.

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Kurt, got to think the weather up there is about to turn if it hasn't already.  We didn't hear from you all summer and wanted to see how your project is goin?  Hope all is well?

JR

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JR   Thanks for your continued interest.  I'm back in town for the fall and winter[back on line] so I can update easier.  It was a slow season for pushing the drifts in my shaft.  I spent much of the summer upgrading infrastructure, as it were...new gin pole, new shaft deck, new dead man, etc.  Also had water issues that have been so aggravating I just didn't want to be down in all the wet.  I did get some thawing done and am very pleased with the performance of my home made thawing rods.  I'll start back in the drift as soon as things freeze up good.  We're also prospecting an old mine's dump piles [not tailings] and will try to keep that going even after freeze up.  Got a couple of young guys helping me out now.  Sure nice to have the extra muscle, enthusiasm and company.

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Yeah buddy, youth is a wonderful thing when it comes to prospecting!  Good hearing from you, keep us posted.

JR

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