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flintgreasewood

Back On The Cobb Prospect Fall 2015

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No, I didn't die at the bottom of my shaft, and I didn't tuck my tail between my legs and slink back to Colorado. A bear didn't get me and I didn't come to my senses and take a "greeter" job at Walmart.

What has occupied most of my time for the past 2 years is the building of a log cabin for my wife and me to live in. That is a story in and of itself but not exactly one that fits the format of the Forum. I also had to find gainful employment to pay bills and keep food on the table and gas in the several tanks. But whenever I could I would get down to the prospect to work on three different projects. The first involved the prospect shaft itself. Once again heavy spring and late summer rains overwhelmed my efforts to stem the constant flow of ground water into the shaft. Digging ditches or draining nearby ponds failed to solve the problem. Thawing muck at the level at which the seepage entered the shaft was continually sluffing off and undermining the cribbing and causing it to slowly sink on one end. It got so bad I decided to rebuild the cribbing. To accomplish this I dug a 3 foot wide trench around the old cribbing, removing layers of logs as I went down. The old crib was around 6’ in height so there was a lot of muck to excavate and haul away with a wheel barrow, but the job proceeded without incident. I knew, though, that as I neared the bottom of the cribbing I would encounter open space beneath the cribbing where the muck had caved away. That made digging a bit precarious as one moment it felt like terra firma and the next there was nothing under the shovel. As I was, at that point, essentially at the base of the old crib, I started building my new crib on the outside perimeter of the old cribbing. After placing 4 courses I had a strong barrier from which to operate around the shaft. Removing the final few courses of crib logs was certainly a challenge mainly due the fact that they were logs I had left in place from the original 100 year old shaft. The last two logs presented the biggest problem; they were completely waterlogged and their excessive weight had caused them to pull away and hang at an angle into the shaft. It required that I lean out from the ladder with one arm while I fastened ropes to the logs. Then holding a chain saw with one hand I leaned down over the new crib and cut the logs in half [with a rope tied to each half] to lessen the weight for hoisting them out. The old crib removed and a new one begun I was encouraged with the prospect of a more spacious shaft out of which to work. Then the rains resumed.

If we were going to be able to winter over in the cabin I had to stick with all the projects involved with it, so I had to leave off finishing the new crib. Also pressing was the need to rebuild and extend the earthen dam I had begun last year so I could have water for steaming once the shaft was cleared out ready for extending the prospect drifts. Last year’s late season rain had taken out a section of my hand built dam but the breech was refilled fairly rapidly with the thawed muck I had uncovered last fall by removing the heavy insulating cover of arctic moss. The little reservoir began to refill and as the water rose so did my dam. Before long I had added enough height and length that I was able to use my wheel barrow to haul loads from the dig site across the dam to the opposite side. To ensure protection against further washout I placed a large piece of rubber roof membrane over the top. A few days later a good rain threatened the integrity of the dam but with a well placed overflow drain dug at one end and with the membrane, it held. At the start of fall and before the ground began to freeze I added yet another two feet in height and 10 feet in width and I covered the entire 40’ of dam with one large sheet of membrane. A small seep at one end didn’t concern me; I thought it would soon freeze. It didn’t. A few days passed after another storm and I thought I should check things out. I found a significant breech that if not dealt with would threaten the entire dam. When I found I couldn’t stop the flow I proceeded to build a causeway across one end of the reservoir to isolate the flow into the breech. It took a bit of frantic shoveling as significant water upstream continued to pour into the reservoir and quickly raised the level as soon as I plugged off the breech. Fortunately I had plenty of thawed muck close by to add to the causeway and after an hour of hard effort I won the battle…or so I thought.

Several weeks passed, heavy snow fell and it looked like freeze up had finally arrived. Concerns for the dam were replaced with the need to finish winterizing the building at the prospect. One day, though, my curiosity to see the snow covered dam and reservoir got the best of me so I went to check. There was almost no water, just chunks of thick broken ice and at the far end where that little seep had been, the seep I thought I had fixed, was a very large breech. Freeze up hadn’t frozen deep enough to stop persistent ground water flow and it eventually eroded a lot of my hard work. Now it’s too cold to do anything till late spring. I’ll have to find some other way to get water for steaming. And when the warm weather returns I’ll have another round of dam rebuilding. Damn!! More to come.

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Water, water everywhere, flowing on top of the moss and seeping along the barrier between frozen and thawed muck and despite my efforts to ditch it away it made its way into the shaft ultimately completely filling it for the third time. The four courses of new crib logs were gradually loosened and soon were floating. I wanted to begin pumping the shaft dry but my pump was frozen in at the bottom having been covered by ice I had removed from the sides of the shaft back early in the summer. It was just as well I couldn’t pump it since I figured out the pressure of the water on the sides of the shaft kept the thawed muck from sluffing off.

The temperature dropped low enough to change the rain to snow and suddenly Cobb was blanketed with around 15 inches. But unlike most heavy first snows in the interior, this one nearly melted off before the serious cold set in and it served to saturate the ground. So even after temperatures dropped below freezing and stayed there most of the day and night, water continued to seep into the shaft. It was nearly overflowing and I needed to do something, so I bought another deep well pump and took the level down 8’. The next day it was almost filled again so I once again pumped it down and once again it was back full the following day. So I cut my losses and let it sit and freeze over, something I shouldn’t have done as that created a lot more ice as the surface of the shaft at ground level was more like a small down about 20 feet. With shovel in hand I climbed out on the ladder which protruded above the ice and pounded away till I had most of it collapsed into the shaft and that’s where it sits at the moment. I may have the steamer up and running by Thanksgiving and I’ll proceed to thaw all that ice so I can continue draining the shaft.

Before I get back to removing the muck that has fallen to the bottom of the shaft I’ll need to do two things. The first is to complete work on the hydraulic hoist system. The next is to finish cribbing the shaft and filling the voids created by the sluffing thawed muck. The plan I’ve come up with for doing this involves one of the earliest operations drift miners employed when sinking a shaft. They had no jack hammers, no steam early on, no excavators, but they had fire. With the abundant wood supply on interior drainages, the miners built bonfires on the shaft site. Next morning they removed the thawed muck, typically about 18” and repeated the process down to bed rock. My idea is to begin a new shaft downstream about a 100’ from the old shaft and haul the thawed muck to be dumped into the voids around the new cribbing. Every night that muck will freeze solid and provide a nearly impenetrable barrier against seepage next summer. Of course I’ll take added precautions to keep things frozen, to include a heavily insulated deck and lid over the shaft

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With my little prospect shack buttoned up it was time to bring in a barrel stove to provide some warmth.  The stove was located at the mine cabin a half mile away on my Babe Creek claim block.  It would be my first time over to the cabin since the snows had blanketed the valley so I had to break trail with my trusty old Skandic snow machine.  The task went smoothly though the stove was much heavier than I had expected.  If I had bothered to look inside I would have seen it was encrusted with at least 30 pounds of clinker and solidified ash.  Back at Cobb I beat on the barrel with a small sledge hammer till nearly all the scale had been loosened, emptied it and dragged it into the shack.  Two days later the stove pipe was in place with a short section of 8" insulated pipe through the roof and a rain cap to top it all off.  I brought down a load of firewood from our cabin and with the help of bit of diesel oil I had a nice fire going.  The stove drew well and it took only about 20 minutes for the shack to be comfortably warm.  Now it was much easier to work on the reconfiguration of my steamer from horizontal to vertical.  In its previous position it presented two significant problems; it belched sickening quantities of diesel smoke into the shack and it was difficult to drain to avoid freezing and rupturing the coil.  In the vertical position I have completely enclosed the coil inside a 55 gallon drum and will be able to vent all the smoke out through the roof.  And when I shut the steamer down at the end of the day it will gravity drain so freezing won't be an issue.

   While I'm working down at Cobb the barrel stove does the job of keeping things thawed out but when I'm away and the fire dies out I need the place to remain above freezing.  To accomplish this I bought and old oil drip stove which I'm hoping will do the trick. I just finished plumbing it in today to a tank outside the shack, but I didn't have a chance to try it out...had to get back to town to watch the Denver Broncos open a can of whoop ass on the Brady Bunch.

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Water in its various states crops up continually as challenges to deal with. The rains of early and late summer play havoc with the trails in the valley bottom and provide endless seepage into the shaft. Then when freeze up comes the seepage turns to ice and coats the sides of the shaft creating a thawing headache. Snow is a mixed blessing as it makes travel and haulage possible where it was not feasible in the warm months. Performing any steaming operation in the months of subfreezing temperatures turns complex. The creek is frozen solid so water must be brought in from another source and in my case that is a spring that I can access 1/3 of a mile from camp. I’ll be bringing a small gas water pump along with a 55 gallon drum and a length of hose hauled in a sled behind my Skandic. I may need to attach a small electric winch to the Skandic to help get up a couple of short steep pitches. Back at camp I can store only one drum of water inside. Other barrels must remain outside where they are subject to freezing. I found a stock tank heater that I’m going to try out soon to thaw out a barrel that has iced up. Hopefully the oil drip stove will keep the building above freezing while I’m not there but I’ll certainly drain the high pressure pump, supply hoses and steam coil before I leave just in case the stove shuts down for whatever reason. Another problem I’m having to cope with is losing stuff under the snow that keeps building up. I am not in the habit of keeping tools and cords up and out of the weather, so one day a shovel will be in plain sight and the next it will have disappeared under the previous night’s new snowfall. hI’m getting better at it but some things will just ave to wait till spring to ever be found unless I accidently stumble on to them.

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