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flintgreasewood

Still Hard At It At Cobb Prospect

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Back in November, Geowhiz wondered what was happening with Cobb Prospect;
was I finished for the season?  In a nutshell...things are ongoing at Cobb
and my "season" never ends.  It's just that what I have been
doing has basically been relatively uneventful .  Though of late that has
begun to change, enough so that I've decided to resume documenting my
endeavors.



   The rains of last summer played minor havoc with my claims in
Fairbanks as they did Geo's in Ophir, though I was not impacted nearly to the
extent many miners were statewide.  Frequently I had to extricate my 4
wheeler from super saturated bogs enroute to the prospect or build makeshift
bridges over my swollen little creek.  But my biggest headache was
incessant seepage into the shaft.  And, of course, there were the never
ending equipment malfunctions. 



   As summer wound down and crisp fall weather set in it became
apparent I was not going to be bringing in the gold we were counting on to help
pay the bills any time soon.  I had to take a job in town.  About the
same time my wife and I realized that wintering through in our little travel
trailer was not really an option so we rented a small “wet” cabin on the banks
of the Chena River at the west end of Fairbanks.  I arranged my work
schedule to have Friday through Sunday off so I could devote time to work the
prospect.  It was a welcome relief to finally have enough money to
purchase some necessary equipment and supplies not the least of those being my
first snow machine.  I knew it wouldn't be long before my old, tired 4
wheeler wouldn't be able to manage the coming snow.  A '93 Skandic II with
reverse and electric start fit the bill nicely.  Fairbanks got its first
measurable snow, 6", at the end of October and that provided barely enough
cover to operate my sled.  It wasn't long before I was grinding along on
bare gravel ever more frequently.  You can imagine I was not enjoying my
first snow machining experience and even considered selling it. 



Fortunately I didn't follow through with that notion.  When finally the
good snow cover arrived I discovered what a delightful experience snow
machining can be.  I bought a heavy duty Beaver plastic sled to haul stuff
in and became a regular Alaska "freighter" transporting everything
from fuel to lumber to wood stoves and generators from my Elliot Highway drop
off down the one mile trail into the valley.



    The constant runoff into the shaft even as temperatures
dipped below freezing inexorably built up on the walls and made the remaining
opening so tight I could no longer get my bucket down.  Seepage continued
till the shaft was filled within 6' of the deck.  Soon it was cold enough
for heavy ice to form on the surface, but I was so frustrated with the whole
mess I found it difficult to deal with the problem. When I finally decided to
bite the bullet and do something about getting the shaft drained my chain saw
came in handy in cutting the ice into manageable blocks for removal.  Then the idea occurred to me to remove the
ice by heating the water in the shaft with my steam coil.  There was still water to be had in the pond after
I broke through the ice to reset the sump pump. 
I  was able to send steam to the
bottom of the shaft for several hours before I had to shut down. I drained the
system and heated the coil sufficiently to remove any remaining water.  Next day saw the same procedure.  The day following I turned on the high
pressure water pump that feeds the coil and fired up the burner.  To my extreme disgust steam began blasting
from the center of the coil.  I had a
rupture caused by water that somehow didn’t get evacuated the previous evening
and had frozen.  That put an end to plans
for warming the ice out.  Any other plan
would require a shaft drained of water , but now the hoses were partially frozen
and one length was also frozen to the side of the shaft.  I was able to pull the pump and one 50’
length of hose.  A propane weed burner
enabled me to thaw out the hose and warm up the pump but I had to get another
length of hose in town before the draining could continue.  Several days later and with the pump setup
complete and in working order I resumed the operation.  All went well and I had 30+ feet of the shaft
free of water and then the pump quit. 
Back up the whole works came to be disassembled to determine the
problem.  When I couldn’t ascertain the
nature of the malfunction I arranged for Ice Water Well [yes, the owners’ last
name really is“Ice”] to check things out. 
A week later they called to tell me I needed a new motor…bearings and
shaft had issues most probably caused by the strain of pumping too much mud.  Another week went by before I was able to get
the pump back in the shaft and get the remaining 30+ feet drained.   With no clear plan to get the ice out I
resumed work on the mine shacks.



    A friend basically gave me several
thousand square feet of foil backed R8 insulation he had salvaged from an old
shop building somewhere near Coldfoot [?]. 
The plan was to cut spruce poles for the uprights and cross members,
sheath them with ½” osb, and overlay that with the insulation.  Ideally the outer skin would be more ½” osb
but I couldn’t afford that, but I had a long way to go before I needed  to worry about what to use.  Always, however, was the issue of the shaft
ice hanging like an ominous cloud over my head, and I couldn’t ignore it.  I could once again mechanically chip it out
as I had done the previous summer and by now I had repaired the steam coil to
thaw the chipped ice, but it would be useless as I had no water supply…the
creek and pond were frozen solid.   Sharing my dilemma with a fellow miner he
suggested an electric heater suspended at the bottom of the shaft to do the
melting.  My generator could handle 3500
watts so I picked up two “milk house” heaters with a max output of 3000
watts.  I bundled the two heaters
together with a trash can lid fixed over the top to protect from dripping water
and lowered them into the shaft.  The 150
watt LED light at the bottom of the shaft revealed dripping water so I knew the
heaters were doing their job.  The problem
was I could see it would probably take several months to thaw all the ice at
the rate it was going.  What next?  I had considered sending the diesel space
heater down but before I went ahead with that idea I saw a compact propane
fired space heater with a btu range of 30,000 to 60,000…substantially more than
the electric  heaters.  Since I didn’t want to send a 20lb propane
bottle down in the shaft with the heater I needed to have a long  supply hose. 
That need was filled by an old 80’ air hose I had laying around.  It was a bit tricky sending down a heater,
hose and electric cord suspended by a ¼” nylon rope.  It worked. 
Even on the heater’s lowest output he water poured down the sides of the
shaft.  But after a couple of minutes the
heater shut off.  I pulled it up, relit and
sent it back down about 15’.  Same
thing.  Tried it a few more times with
the same result.  It became apparent the
oxygen was being used up and the CO was extinguishing the flame.  I connected an air line from a small
compressor to the intake of the heater to supply additional oxygen but it wasn’t
sufficient to keep the heater lit.  I
needed to either suck out the heavy CO from the shaft or force a large volume
of air into the shaft.  Either way I
needed a large blower fan and some flexible ducting.  I got a slavaged furnace fan and 6 10’
lengths of corrugated drain pipe.  I
first rigged the fan so as to suck the CO. 
No matter where I placed the ducting…on the bottom or right below the heater
the flame went out after a few minutes. 
It was evident a large volume of air needed to be force fed to the
heater, so I accomplished that with a 4 inch flange and an elbow and a few feet
of bailing wire.  So far I’ve run the
heater for about 4 hours uninterrupted and the ice is disappearing
rapidly.  I’ll keep you posted how that
goes.



   I’ve discovered the usefulness of
rubber roof membrane and I determined it would be a fine exterior skin for my
mine shacks.  There are quite a few
roofing companies in Fairbanks and I found one that had a pile of salvaged
membrane I could have.  It was snow
covered and partially frozen to the ground and it was HEAVY.  With a shovel and a 2x4 pry bar I managed to
loosen the pile enough to get a tow strap attached so I could pull it free and
out where I could lay it out and cut it into three manageable pieces.  Well, almost manageable.  Two of us could barely lift each piece into
my pickup. I got a 50’ x 30’ piece for $50!! 
What a score.  Back at the mine I
realized I would have to keep the rubber skin from crushing the insulation so I
accomplished that with short posts through the insulation, fixed to the inner and
poles across the posts.  I now have one
of three shacks covered over.  Much of my
efforts have taken place after dark under flood lights and a headlamp.   At first I was reluctant to work at night
but now I have come to actually enjoy it.  Here in Alaska in the winter if you wait till
it’s light to get busy, you’ll not get much accomplished.  I’m also learning to be adept at performing
many common tasks wearing heavy gloves or mittens.  It takes patience, perseverance and a little
bit of idiocy to work out doors, at night in the arctic winter.  Though I must concede, this has been a mighty
easy going fall and winter so far up here in the great North.  And from what they say, it’s supposed to
remain mild for the duration.  Waaaah!


 

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Kurt, good to get an update from you.  Talk about the need to be resourceful, nice job and another demonstration of the multiple hats a prospector needs to wear.  Hope the winter is treating you well!

 

JR

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Chuck,

   I appreciate your concerns for my safety.  To allay your fears, though, I should tell you that I don't go down in the shaft when I'm using the burner.  I couldn't even if I were inclined to...my ladder is frozen over.  When it does come time for me to go down in the shaft, I will thoroughly evacuate any gasses and replace with fresh air.  I'll most likely take three days running the exhaust fan to be sure it's clear.

   I certainly want to use steam and I do have everything set up to do that except for water.  And, yes, I could melt snow and have considered doing that.  I've just not been able to come up with a viable plan to accomplish it.  It takes a lot of water to keep my steam coil happy, about 55 gal every 30 minutes.  Currently there is about 14" of powdery snow in the valley.  It would be very difficult scooping it up with all the vegetation beneath it.  Even if I could collect enough snow to melt down I would have to build a sufficiently sturdy platform on which I could place melting vessels under which I could set a wood fire [in writing this I have come up with some ideas].  More on this later.

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Chuck,

   I've decided I should relate an example of the dangers you aptly and emphatically warned of.  Fortunately I am still here to do the relating.

   I was able to successfully modify a small propane space heater to fire up while down in the shaft thereby avoiding having to haul up the heater with its attached electric cord, propane hose and 4" fresh air ducting every time I needed to relight it.  First off red flags should go up whenever someone modifies any gas related device. Don't try this at home kids!  Typically I am color blind...at least to red!  What I did to make the heater work as described was to permanently hold down the heat selector/auto ignition knob with a screw.  After turning on the gas at the bottle, I merely had to plug in the power cord and the heater would begin operating at its lowest heat level.  To cut off the burn I had to shut off the supply at the LP tank and pull the power cord or kill the generator.  Simply turning off the power served only to turn off the heater's fan; the gas continued to burn inefficiently but burn nonetheless. 

    When it came time to quit work and go home I shut down the generator, packed up my gear and drove on up the hill on my snow machine.  Instead of going home I decided to have dinner at a nearby truck stop and while dwelling over my second cup of coffee it hit me that I had forgotten to turn off the propane.  Even though I'm really good at rationalizing myself out of doing things that are a bit more than inconvenient [it was 9pm, about 15 below, and I was tired] I knew I had to drive back down to the prospect and take care of business.  When I opened the door to the shaft a very acrid odor greeted my cold nose and I realized I was not going to come out of this one unscathed.  But I also knew nothing worse than what had happened could take place now that the gas was turned off, so I left things be to be dealt with in the daylight the next day.  

   To be continued.

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It was about 11 am on Saturday when I returned to the prospect.  I unloaded the pieces of plywood I had scavenged from the waste transfer site and hauled down on the sled then turned to dealing with the mess in the shaft.  The nylon rope, the propane hose and the power cord came up unattached except for the steel trash can lid that served as a shield.  Beneath the lid was the melted plastic heater handle and the power cord had burned and bare wires at the end.  The 4" plastic air ducting came up next with a melted PVC elbow hanging off the end.  The heater itself was tangled in other ropes and power cords and remains down the shaft.  To remove the bad air I refitted the air duct to the intake side of the squirrel cage fan and let it run for the entire day.  At this point I have no reason to go down in the shaft but when I do I'll take a CO detector with me, just in case.  Did I learn my lesson?  Well, I'm almost 70 years old and I'm still doing stupid stuff.  I try to be careful but it's just not in my dna.  Guess that's why all the MSHA regs may just be a good thing for me.

    I still had the two "milk house" heaters I could thaw with so I rigged them up and sent them down and returned to insulating and weatherizing the building.  There was plenty of fiberglass batts to run two layers on the roof and sides.  I had to be careful on the pitched roof as frost on the foil backed insulation made for a very slick surface.  That done it was necessary for me to wrestle the 14' x 40' piece of rubber roof membrane up on the roof.  Due to the subzero cold it was a bit stiff and I needed to lay it out flat on the snow so I could fold and roll it up in a tight bundle.  Fortunately, the rubber stays somewhat flexible even when very cold, so I was able to curl up an edge to get a grip and then drag it with all the strength I could muster.  Once flat it was a piece of cake to fold.  I dragged the rubber "log" to the easiest place to access the roof, stood it up on end and shoved it up inch by inch till it began to fold over and then it could tip it the rest of the way.  Unrolling and unfolding went smoothly and now I have a waterproof roof and sides of my little shack.

  I'm off to Colorado for 7 weeks to work with my brother, so I'll not be working the prospect till I return in April.  Till then, stay sane the remainder of winter.

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