We stay local for this story. In 1859 a major gold discovery was made at what became Central City, Colorado. It was a rich find, and the mountains for miles around held more gold. Within a few years the area was honeycombed with mine tunnels reaching hundreds of feet underground.
Deep mining has some inherent engineering problems, one of them the problem of groundwater seepage. Many tunnels became flooded as nineteenth century technology couldn't drain the water as fast as it came in. The rather ingenious solution came in 1893 when work started on the Argo tunnel in nearby Idaho Springs. Idaho Springs sits about two thousand feet of elevation lower than Central City, and the surrounding mountaintops higher still. The Argo tunnel undercut many mines by drilling more than four miles nearly horizontally. Not only water but the ore from these mines was lowered into the Argo and then shipped out, which was much easier than raising the rock up to the entrances of the mines.
Fifty years later the Argo was still in operation, and then
It was on January 19, 1943, about quitting time, that a small crew of four miners worked to set off the last charge of the day. Conditions were miserable, the Kansas Shaft had quit pumping water anticipating that the Argo crew would find the shaft and drain it. The whole Nevadaville area was flooded with water twelve hundred feet deep; many of the flooded mines above the Argo were leaking into the tunnel; it was wet and hard to set off the charges.As the miners would drill holes for dynamite charges, the water would squirt out the seams under high pressure, it was later estimated the water pressure was over five hundred pounds per square inch.
You can guess what happened next. The rock between the Kansas Shaft and the Argo tunnel gave way. The result was the Argo turning into something like a giant fire hose. If you can believe the locals the four unfortunate miners and their ore cars were shot several hundred yards across the valley. The January temperatures froze the water and turned it into an ice dam which blocked Clear Creek which in turn flooded buildings in Idaho Springs.
The seeping water from all those mines still runs out through the Argo. Those gold veins are multi-metallic, containing aluminum, zinc, copper, manganese, cadmium, lead, arsenic and others. That stuff dissolves and comes out in the water. Nowadays the Argo is a Superfund site.
Posted by Walter at December 1, 2006 03:26 PM