CSCE 2007 Annual General Meeting & Conference Congrès annuel et assemblée générale annuelle SCGC 2007
Yellowknife, Northwest Territories / Yellowknife, Territoires du nord-ouest June 6-9, 2007 / 6 au 9 juin 2007
Yukon Aerial Tramways - Wire, Wheels and Buckets in the Canadian North Ken Johnson, Earth Tech Canada Kevin Johnson, City of Nelson B.C. Abstract The placer gold mining “rushes” of British Columbia and the Yukon in the late 1800’s gave way to a silver “rush” in the late 1800’s and early 1900’s in the same regions of Canada. The southern interior of British Columbia experienced a rush that whose legacies still endure to this day, whereas the Yukon’s silver rush is all but forgotten. Small scale placer mining required a fairly low level of technology compared to the demands for silver mining. Silver mining required modern technology for extraction, transportation and processing, and the engineers and manufacturers of the day were able to respond with many marvelous machines. Key to many silver mining operations of a century ago was the aerial tramway used for transporting ore from the mine site to a smelting operation, or some other inter model transportation facility. These “wires, wheels and buckets” were able to operate on gravity alone, and transported ore over rugged terrain. The pioneer of aerial tramways in North America was an engineer named Byron Riblet, who got his start in the Kootenay Region of British Columbia. The early influence of the Riblet expertise extended across the northwest, and ultimately into the Yukon with the construction of the Montana Mountain aerial tramway in 1905. This installation was over 5.5 kilometres in length with a vertical rise of over 1,000 metres, and one recording setting span of nearly 900 metres. The Montana Mountain mining activity, and the associated community of Conrad City, Yukon were short lived, however, much of the Riblet aerial tramway endures to this day as an historical artifact to the Yukon silver mining boom.
1. The History of Yukon Mining Although the gold strike of the Klondike River is the most famous mining discovery in the Yukon, previous discoveries were made in Yukon River tributaries downstream of Dawson City toward the community of Circle, Alaska, 300 kilometres away. Production began in the mid-1880s with discoveries along the Fortymile River, which is 75 kilometres downstream from Dawson City. In 1895, gold was found on a series of creeks just downstream of Dawson City, and by 1896 active mining was taking place on all the principle streams in the region around Circle, Alaska. The Klondike River gold discovery in August 1896 was the discovery that brought fame to the region, and a stampede of 40,000 people.
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In the years following the Klondike Gold Rush, the population of the Yukon Territory fell dramatically as the placer gold fields, worked by an individual or small groups of miners, were taken over by large river dredging operations. These dredges were owned by well capitalized foreign corporations, processed enormous amounts of gold-bearing gravel, and needed few men to operate. Mining dredges were in fact encouraged by the Territorial government, which saw them as the key to the economic future of the Yukon. For the independent miners who remained in the Yukon, any rumour of a new mineral discovery was cause for a stampede to the area. The most dramatic of these stampedes occurred in the spring of 1905, with the development of silver claims on Montana Mountain between Windy Arm and Bennett Lake in the southern Yukon. 2. The Geology, Geography and Topography of Montana Mountain The geology of southwestern Yukon and the Windy Arm area is complex as a result of the past 200 million years of movement of the plates that make up the earth's surface. Montana Mountain is situated at the junction of the Whitehorse Trough and the Coast Plutonic Belt, which collided 150 million years ago. The subsequent buckling of the earth's crust and the volcanic activity associated with that collision, helped form the Coastal Mountain range. At Montana Mountain the movements along the geological formations have resulted in a complex weaving of the volcanic and sedimentary rocks that have formed at various times over the past 50 to 150 million years. Most of the important mineral veins have been found in the band of minerals that forms the shell of Montana Mountain. In this formation, gold and silver have deposited from mineral rich thermal waters in the fissures opened and closed by the plate movements.
Figure 1. Montana Mountain region
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Montana Mountain and the nearby peaks are located just north of the 60th parallel, and the British Columbia – Yukon border (see Figure 1). Montana Mountain is the highest of all the peaks in the immediate area at 2200 metres; the surrounding peaks are generally 1800 metres or lower. The mountain is located about ½ way between Bennett Lake and the Windy Arm of Tagish Lake, which both run north-south, and are both situated at an elevation of 655 metres. Drainage from the mountain area flows west into Bennett Lake, east into Windy Arm and north into Nares Lake and Tagish Lake. Access to Montana Mountain developed from the north because of the gradual terrain slope in the 11 kilometres up from Carcross. To the east and west, the terrain drops off relatively steeply in 7 to 8 kilometres down to Bennett Lake and Windy Arm. The mineral deposit discoveries of the mountain were within 5 kilometres of Windy Arm, so the development access focused in this area. This proximity of Windy Arm lead to the development of the 5700 metre long Montana Mountain tram, which started from a small bay on Windy Arm, and ended 1060 metres above, to the west, at the Mountain Hero claim (see Figure 2).
Figure 2. Montana Mountain tramway alignment southwest from Windy Arm 3. The Technology of Hardrock Mining and Aerial Tramways Small scale placer gold mining required a fairly low level of technology compared to the demands of hardrock silver mining. For smaller operations, hardrock mining was still back-breaking, dangerous work for the men underground, using techniques that had changed little since men first started following veins of gold and silver into the earth (see Figure 3). Tunnels were kept as small as possible, ventilation was poor, and the only light in the working area was provided by candles. The use of explosives was limited almost entirely to the first few metres of a new tunnel because of the problem of venting the tunnel after the blast.
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Figure 3. Tunnelling on Montana Mountain Hardrock mining on a large scale required modern technology for extraction, transportation and processing, and at the turn of the century mining technology was advancing rapidly at the leading edge of scientific development and industrial requirements. The traditional means of transporting ore from a mine site was by horse with ore in a leather sack (called rawhiding); this means of transportation was obviously very inefficient, and limited large scale mine development for sites any significant distance from boat or rail access. The advancement of tramways in the transportation of ore came about as result of innovations in the application of wire rope in the mid 1850’s. The innovations of Andrew Hallidae in the 1870’s, not only produced aerial tramways, but also the cable streetcars that remain an icon in San Francisco. The principles of the first aerial trams were quite simple, buckets were attached to cables, which were supported on towers with sheaves (wheels) for the cable to run on – gravity did all the work to pull the buckets down from the loading point to the dumping point. In practice, a tramway system is a reasonable complex mechanical system that must manoeuvre over rugged terrain. Filling and emptying stationary buckets could be accomplished quite easily, but a bucket in motion required a sophisticated series of wheels, track and levers to operate. An experienced young engineer from Spokane Washington named Byron Riblet ventured into the Kootenays in the late 1890’s just as the silver boom exploded in this region. By chance he received an assignment to design a tramway for a local mine using the cable streetcar experience from Spokane, and observing the existing tramway systems in the region. In typical engineering fashion Riblet recognized that the current state of technology could use some serious improvement in all aspects. The innovations of Riblet included wire rope and bucket clips, sheaves, tramway derricks (towers), bucket loaders, and bucket dumpers; almost 20 patents were registered by Riblet in the period of 1900 to 1910 (see Figure 4).
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Figure 4. Patented Riblet tramway components: (L-R) bucket, tower and rope grip attachment. 4. The Constructors and the Construction By the time of the Windy Arm “rush� in 1905, a flamboyant American mining promoter named John Howard Conrad had acquired control of most of the newly-discovered gold-silver-lead deposits. Conrad managed to raise the enormous amounts of capital required for development work from some of the most high-profile financiers in Canada, the United States and Great Britain. In August, 1905, sixty men were working on three main groups of properties; on the adjoining Mountain Hero and Montana claims, forty men were working three eight-hour shifts, another twenty working on the nearby Venus and Uranus claims. Shafts and tunnels were being driven in at least a dozen places. Conrad made a quick trip to Seattle in July, 1905, and ordered a Riblet aerial tramway. A deal was made for the tramway to be installed as soon as possible to assist in the development, and to haul ore from the Mountain Hero Mine.
Figure 5. Montana Mountain tramway tower #6 assembly in 1906.
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In early August, 1905 the first materials for the Montana Mountain tramway arrived from Spokane, Washington at Skagway, Alaska. A large crew of men loaded twenty-two rail cars on the White Pass and Yukon Railway with timbers for the towers, lumber for the terminals, and several tons of iron and steel tramway parts. Construction began five days later when the materials arrived on to the beach at Windy Arm. Twenty-five mules were diverted to the task of getting the materials up the mountain to a construction crew of fifty men brought in for the job from British Columbia. The tramway, which cost $80,000 (1905$), was of bi-cable design, with the ore cars riding on a heavy stationary support cable while being pulled by a lighter "running" cable (see Figure 5). Crossing over two canyons, the tramway was designed with the longest span between towers in the world at 900 metres. Suspended from the cable were about 80 ore buckets, each carrying 0.33 cubic metres of ore; travelling at a little over 8 kilometres miles per hour, it took about fifty minutes for a bucket to travel from the mine to the discharge terminal at Windy Arm. There were also several lumber carriers, and several single-passenger chairs which were attached to the cable as needed, allowing men to reach the mine quickly, and in reasonable comfort physically. One of the factors that needed to be calculated into the design of the tramway was the fairly uncommon situation of using the tramway to transport some of the smaller construction materials up the mountain as well as ore down. As a result, the support cable for the ore cars travelling up the mountain were 28.5 millimetre in diameter instead of the standard 19 millimetre. During September, 1905, work went on at a frantic pace to get as much as possible done before the snow fell. The 27,400 metres of steel cable needed to complete the tramway was delivered, and the heavy work of laying the cable began. The simple broken capstan, used to layout the steel cable, was delaying the completion of the tramway, and unfortunately a replacement capstan shipped from Seattle had been the wrong part. The White Pass blacksmith shops in Skagway were finally approached to solve the problem, and after they attempted to repair the broken casting, with no success, they decided to cast a new one. The capstan was installed in early November and the cable installation continued. A particularly mild spell of weather had melted most of the snow off the south slopes, greatly facilitating the work that was expected to be a 10 day operation. The Montana Mountain tramway was first operational in late June 1906. Once operational, the tramway was bringing down ore from the Mountain Hero Mine and the adjacent mines, however, the practical limits on tramway length and tower spacing had apparently been exceeded because breakdowns plagued the operation of the tramway. The tramway was designed primarily to carry ore down the mountain, with gravity as its only means of power. To get buckets carrying 100 kilograms of supplies to travel up the slope, it was necessary for the down-going buckets to be loaded with about 500 kilograms of rock. As limited ore was available to load the buckets, it was necessary to keep loading loose rock from the mountainside into buckets in order to power the tramway. By 1907 Conrad was employing over 350 men in the mines and an ore concentrator, while he had another 150 men were scouring the hills in search of further rich mineral deposits. Conrad City had developed into a community with a population of 500 people, six hotels, hardware and grocery stores, butcher, barber and blacksmith shops, several churches, a hospital, a newspaper, a telegraph office, a District mining recorder and a Mountie detachment. 5. The Legacy of Montana Mountain Despite the reports of one year previously, the tunnel on the Mountain Hero claim, at the top of the tramway, had not found the main Montana vein. The vein was ultimately a small one, which soon tapered off. When further tunnelling revealed only more barren ground, work on the claim was suspended. The location of the tramway quickly became quite inconvenient for ore conveyance because of its distance from the other nearby claims, although it was used to carry supplies from Conrad City to the claims. By 1909 several thousand tons of ore had been shipped off to a southern smelter. Although some of the ore graded as high as $5,000 per tonne, in general, the ore veins proved to be discontinuous, and of a
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considerably lower grade. The stories of the richness of the mines were too good to be true. Conrad Consolidated Mines slipped into bankruptcy in April of 1912. In spite of the ultimate failure of the Montana Mountain mining venture, it can be claimed with justification, that the project investment of upwards to $1 million in capital, thrust the southern Yukon out of a stagnating post Klondike depression.
Figure 6. Montana Mountain tramway tower #6 in 2006. The lasting legacy of the Montana Mountain mines is that the cold climate of the mine’s location has preserved the long forgotten technology of aerial mining tramways. The many Riblet tramways constructed in southern Canada have either fallen to scavenging or to the elements many decades ago, and the historical records of aerial tramway technology are essentially non existent. Even the Riblet Tramway Company itself has little or no records of the aerial tramway history of the company’s founder, focussing on the legacy of the aerial ski lifts that developed directly from the mining tramway technology. A visit to the abandoned townsite of Conrad City, and the slopes of Montana Mountain reveals many tramway towers in pristine condition after a century standing on the slopes of the mountain. The old packhorse trail that was originally built in 1905 for the tramway construction by the legendary Yukon road builder Sam McGee, has been reclaimed, and provides a trip back in time to the 18 month silver boom of the Yukon.
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6. References Lundberg, Murray. Fractured Veins and Broken Dreams: Montana Mountain and the Windy Arm. 1996. Wells, Martin. Tramway Titan: Byron Riblet, Wire Rope and Western Resource Towns. 2005.
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