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flintgreasewood

2014 Mining Season At Cobb

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How it all got started is history.  The 2014 mining season has begun
and my wife, Alethea, and I have big plans to put into play here at Cobb
prospect north of Fairbanks, AK.  We arrived with half of our possessions,
three vehicles and one trailer a week ago after a hassle free 3000 mile journey
from our former home in Colorado.  I say "former" as we plan to
stay put up here for at least 3 years so we can get our claims proved up and
eventually sold.  I'd like to have the underground mining experience for a
year or two but I'm getting too old to set my sights on 10 or 15 years of arduous
work even if the end result is gold.  So the overall plan for the summer
is to resume work in the shaft where I ended up last summer...67 feet down into
the permafrost on bed rock.  Along the way I'll be getting my old
International TD-15 track loader/dozer up and running so it can be used to make
and grade roads and drag around our newly acquired skid mounted BE-21W cable
tool drill rig.  The drill will be used to put down several water wells
this summer and then for sampling the claims after the ground is frozen. 
I'll also be working from time to time on some claims other than my own to
provide some financial help until we can.  I'll also be working from time to time on some
claims other than my own to provide some financial help until we can begin
producing gold from our ground.  And that isn't going to happen quite as soon as I had planned. Funny how that goes!



   Doug had prepared me last fall for
the new ice I would find in the shaft.  A
heavy late fall rain had nearly filled the shaft and it had, of course, frozen
through the winter.  So the first order
of business was to thaw the ice cap and pump out the entire 60 feet of water
that remained beneath the ice.  Setting up
the steamer was new to me as Doug had done that last summer, but it wasn't
difficult to figure out.  I set the
submersible pump in the pond and got it filling the 55 gallon drum supported on
the roof of the steam shack [for gravity feed], connected the hoses to the
pressure pump and steam coil and placed the fuel line to the burner into the
diesel can.  When the water reached
capacity in the drum, the pump was started, the coil filled and the burner
fired up.  Within five minutes I had 30
lbs of steam pressure, enough to begin melting ice.  It didn’t take but a few seconds to punch
through the cap in the center of the shaft but I could not break through on the
sides…not good!  I honey combed the cap
with holes till I was able to open a large enough hole to get my pump
down.  I set the pump on the bottom and
let her rip.  It took about five minutes
to fill a 55 gal. drum.  After drawing
down the shaft to about 20 feet I shined a light down to check the
progress.  To my dismay I could see that
the ice had built up thick on three of the walls and in some places covered
over the ladder.  The opening was barely
18” x 40”, not enough to get my bucket up and down.  For several hours I lamented my situation and
tried to come up with a viable method of removing the heavy glacial buildup.
Then it hit me, I didn’t have to remove ALL the ice, just enough to clear the
ladder and to allow for the free movement of the hoisting bucket.  In fact, the encroaching ice would actually
be a blessing as it would help keep the drifts below colder.  Hey, when life serves up lemons…make
lemonade!  Now I still had a  bit of a dilemma…how to remove even a small
amount of ice.  A small man lift looked
to be a likely solution and I had all the materials right there to build
it.  I designed and built it on the fly
and came up with a 16” x 13” plywood platform with 40” side posts made of 2x4’s
and a 2x4 rail around the top.   3/16”
aircraft cable looped through 4 large eye bolts was brought together three feet
above in a carabineer which was attached to a winch cable.  Just for safety I also decided to use a fall
arrester and harness attached to a 5/8” climbing rope that ran to the bottom of
the shaft. To operate the lift I had a remote pendulum switch on a 70’ cord.
For illumination I fixed a large LED flood light to the rail.  I even attached a lanyard to my rock hammer
and tied it to the lift.   For an
overhead pulley I simply positioned the self dumping bucket carrier over the
shaft and used one of the pulleys in it. 
To alleviate the bounce in the high line I propped up the cable with a
spruce pole and a ladder of convenient height. 
It all looked good so I put on my rain suit, got in the safety harness,
gritted my teeth and looked for a way to get in the contraption.  If I could have placed the lift on the
decking next to the abyss it would have been easy to get in, raise the lift and
swing out and down.  Problem was that I
couldn’t raise the lift high enough before the carabineer ran into the pulley.  So I had to enter with the lift suspended.  I lowered it just enough so the top rail was
even with the deck.  I merely sat on the
deck and slid myself over into the lift. 
Fortunately I’m of slender build so I just barely squeezed into the lift
with the cables pinning my shoulders.  No
sweat!  I had to keep pulling slack on my
safety line as I lowered myself to where I could begin chipping the ice.  There was not clearance enough for the lift
to descend so I had to first reach down and chip down to the platform.  When I had the lift free to descend I
concentrated on clearing the ice from the ladder.  I got a couple of rungs done and by then it
was getting late so I called it a day, a successful day at that.  I came up, exited the lift with more aplomb
than my entry, called my wife to let her know I made it down and up and out
without incident and would soon be on my way home to a late dinner. 

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      The next time
down at the mine I was a bit more adept and confident  in my entry into the lift.  It had proved itself a trustworthy and
functional piece of equipment and one that I will probably use from time to
time in the near future.  When everything
was fixed in place I began lowering myself to the level at which I ended the
previous  time down.  For a few feet the shaft ice was thick enough
that the lift had to be swung over to a place that was just wide enough to pass
through.  However, when the opening
became a bit more spacious the lift would swing and spin when I tried to apply
pressure with the hammer drill.  This was
quite frustrating and a substantial waste of energy so I had to resolve the
problem.  I noticed the ladder rungs were
now free of ice so I reached out and placed my right foot on the solid footing
of the ladder which forced the lift a foot or so to the opposite side of the
shaft where it was held fairly securely. 
I now had both unobstructed space to work with the lift styles out of
the way and a good platform from which to chip ice from all directions.  It wasn’t long before I had a good system for
hitting both side walls, taking off 3 to 4 inches  three feet at a pop in just a few
minutes.  I was delighted with the speed
at which I was able to zip through and by day’s end I had removed almost 40’ of
ice.  It all lay glistening 15’ below me
ready to be transformed to liquid by the steam point.      Once the steam coil was stabilized at
about 55lb. of pressure I was free to attend to other small jobs that didn’t
take me too far away from the area immediate to the steam shack.  There is always house keeping, ie, coiling
ropes, cords, wire and hose, putting up tools that get spread all over the
place and cleaning up mess of various sorts. 
But I always must keep my eye on the water level in the supply barrel
and refill it from the reserve barrels. 
These also need to be refilled from the pond using the sump pump that
also fills the supply barrel.  So that
requires shuffling the pump back and forth from barrel to pond along with the
hose and power cord.  After 4 or 5 hours
of steaming I turned on the submersible pump and pumped out over 200 gallons of
water.  There was still a layer of ice
over the cavity created by the pumped out water so I climbed down and stomped
on the ice till it crumbled through to the bottom.  Then it was back in the lift to do more
chipping, followed by another steaming and pumping.  I did this two more times till I was finally
standing on the floor of the shaft and able to begin widening the area at the
entrance to the iced in drift.  To do
this work I had to sit in a combination of ice water, chipped ice and muck.  Of course I was wearing my rain suit so I
stayed dry, though not very warm. 
Though  the quarters were very
cramped, it was rather enjoyable working my way into the drift.   But now it was time to get the new hydraulic
hoist in place.



    I had brought the
340 lb hoist down to a staging area with my pickup but from there it would have
to be transported a half mile in a sled towed behind my four wheeler.   I secured it in the little sled as best I
could with ratchet straps but the rough trail I had to negotiate with such a
compact mass took its toll on both straps and sled and I had to retie several
times. In one particularly boggy section of trail the sled flipped upon hitting
a small stump and dumped the hoist, half submerging it in the mud.  Fortunately this particular hoist is built
for the most extreme weather conditions so a little water and mud is of no
concern.    With some difficulty I was
able to reload the hoist in the sled but the Polaris, which was also partially
stuck in the bog, could not move the sled. 
I had to drive ahead to more solid ground and winch the sled free with a
come along attached to the hoist as well as the sled.  I pulled my load up as close to the place the
hoist would be secured as possible and then winched it the remaining distance
using a small birch to lift it into position. 
I held the hoist in place with straps around the tree to which I had
already fixed small logs that the hoist would ultimately be bolted to.   The two hydraulic supply hoses were ready to
connect as soon as I swapped out the fittings from my old defunct  hoist. 
The 16 hp engine fired right up, I moved the valve control lever and the
drum turned.  I reversed it and that
worked too.  But just as I had expected,
the engine and pump were set up for a hoist ¼ the size of the new one.  I quickly calculated the hoist direction at
about 22 feet per minute and lowering direction at a whopping  15 feet per minute…agonizingly slow!  So I’m currently searching for an engine 25
hp or larger and working on converting a large hydraulic motor to a pump.  But for the time being I’ll just have to live
with slow and steady.  Next was to
install 500 feet of ¼”’ wire rope.  I
first, unsuccessfully, tried to hang the 60lb spool from a birch stick chained
to a black spruce and spool it off. 
Next, I grabbed a piece of pipe and held the spool in front of me while
I walked it out through the mossy tundra. 
The only consolation in that method is that each step made the strain on
my arms a few ounces lighter.  It felt so
fine to reach the end of the line.  Since
only 250 feet of that cable would be needed as hoist line I measured off that
much in 25’ increments, placed a bit of tape at the proper point and loaded the
hoist drum with the remainder.  Then I
climbed the gin pole, fed the cable through the snatch block, then back at the
shaft, fed it through the bucket pulley and up into the carrier to where is was
fixed with cable clamps.  Though slow,
the system worked just like it’s supposed to in the hoist mode.  However in descending, the carrier was so
slow that there was not enough force to move the latch over the catch pin.  A faster moving hoist will solve that
problem.  While operating the carrier I noticed
that the high line was sagging significantly and that even without a load.  The line had to be tightened.  I went to it’s anchor point and  began turning the  turnbuckle. 
Things were going well when suddenly all went slack.  Upon investigation I discovered the 3/8” eye
bolts I used at the gin pole had pulled the eye straight on the high line side
and almost straight on the opposing guy wire. 
I’ve now resolved that problem with forged eye bolts.  I also took some of the surplus 1/4”  cable 
and replaced the far too short and badly positioned  opposing guy wire with one three times as
long and in direct opposition to the high line. 
Tomorrow I’ll tighten up the high line and see how strong the new
setup  is.


 

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Amazing how the stresses get out of control so easy and straighten eye-bolts. Welded or forged is the only way to go. Slings are another place to get in trouble with stresses. Don't take chances. Gravity isn't just a good idea, it is the law.

For those who need info on rigging (lifting and moving heavy stuff) here is a great resource for that info.

http://www.enlisted.info/field-manuals/fm-5-125-rigging-techniques-procedures-and-applications.shtml

You can download by the chapter and save. There are other sources for FM5-125, but I trust the military site to be safer.

eric

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I have been following this adventure by Flint with much interest. I do have many questions but find that most are answered if I just keep reading. I do have one that I'm really curious about and that is just how large(dimension) of a diameter or cross section is the vertical shaft Flint is working in?

 

I'm 78 years old with the itch but will have to be content to just follow you folks around via this box of rocks called a computer. I'd be there with you if things were different, I guess we all have that bridge to cross as time goes on.

 

dick

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Hello, Dick

I plan to post another report on progress, or lack thereof, at Cobb prospect soon, but I'll answer your question now.

The shaft as originally dug by the old timers was approximately 6'x 3.5' and 67' deep [to bed rock]. My first two summers of work on the shaft were spent mainly removing all the ice that completely filled the shaft and small drifts. Last fall the shaft refilled with rainwater after a big storm and I wasn't there to pump it out. Consequently, it nearly froze completely back but there was barely enough room to lower myself down on a skip so I could chip enough ice out to get a bucket down. So right now the shaft is roughly 4' x 2.5' with one end rounded and the other with the ladder against the wall. Working at the bottom I have a little cavern thawed out that makes it just a bit easier to operate, but with a half of a 55 gal bucket, pump, jackhammer, ladder, and hoisting anchor weight sharing the same space, it's not very roomy. I'll try to post some photos soon. Hope that helps.

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Dick,

I don't have a claustrophobia issue but at first I was uncomfortable with the thought of being so far down with barely enough room to turn around. Hard work in a situation like that helps take your mind off those thoughts. Also troubleshooting problems from the ladder 40' or 50' above the bottom, hanging by one arm around a rung is not as difficult as it might seem. One needs to do what needs to be done and you don't let it get to you.

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Flint,

 

One needs to do what is safe. :)

 

Doing things that are or possibly could cause one's own demise on a continual basis will, in fact, eventually catch up. The most difficult part of underground mining is mitigating the risk that surrounds you.

 

The man. The man in the hole could suffer a long list of unexpected injuries. The man over certain age is statistically more vulnerable. The reflex takes longer, usually there are impairments in vision, hearing, and general muscle coordination. Memory loss causes several added issues related to safety. Forgetting that you were going to remember that the bolts needed to have nuts on a structural piece and getting reminded the hard way is an example. It's one thing when your wife reminds you it's worse when a two by four hits you in the head!

 

So, older workers do suffer injury more often. In spite of that, they continue to work at diminished capacity. Working at diminished capacity increases the risk of additional injury. It's a revolving door of added injury until one is incapacitated - unable to work.

 

So, the tweety bird on your shoulder is excused! :)

 

- Geowizard 

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