ODDS’N’SODS — Avalanche! (2)

(The following is the conclusion of a 2-part article in which the author describes a series of avalanches he experienced first-hand while working near Rogers Pass, B.C., in 1974.)

The two events last described were mere snow slides — ponderous masses of snow detached from a larger, unstable mass lodged no great distance up the mountain side.

But in fewer than 24 hours, we had a close call from the real thing — an avalanche. A mass of snow travelling with the speed of an express train, gaining ever-greater momentum on its downward run and generating its own violent wind ahead of it. Anyone within a half-dozen miles that night would have heard it. A nerve-chilling roar, the sound of treetops being lashed as in a gale, then . . . silence.

Within moments, everyone was outside expecting to see wreckage. But it wasn’t until daylight arrived that we searched far enough. One of the original bunkhouse complexes of the mine, half-a-mile further down the valley, had been struck. It was no longer occupied and hadn’t been used for years. In hindsight, it was almost inevitable the mine would be hit next. We’d had enough warnings. But, if anyone had thoughts of pulling out, he had left it too late. He should have made his move within hours of our examining the wreckage at the old camp.

Hours after the event, we learned the precise moment the avalanche struck the powerhouse. It was 8.40 p.m. That was the time the lights went out and the electric clock stopped.

A minute or two before 8:40, a booming roll heralded the avalanche’s first moves 2,500 ft. above us. It grew louder by the moment. Abruptly, a puzzling quiet interposed for a few seconds. (Perhaps an intervening ridge on the mountain slope momentarily diverted the sound). Then it was on us. The booming roll became a full-throated roar. A flood of pulsating sound filled the air.

In seconds, floor, walls, everything in the building that was solid, vibrated. Simultaneously came the nerve-chilling sound of the snow-mass itself. Overiding all was a near-continuous explosion as a hail of tree debris, clumps of ice, anything in the path of the avalanche’s air blast, was flung against the building. Its sheet-metal roof made it a drum. The noise and vibration were intolerable. The house was a maelstrom of sound. Then — utter stillness. It was over. From beginning to end was fewer than five minutes. Five minutes and a lifetime.

Two mornings later, the helicopter arrived to ferry us back to civilization. It was a beautiful winter’s morning — brilliant sun, cloudless sky and an atmosphere clear as crystal. We had a perfect view of the mine as the helicopter lifted off and circled the camp.

From the air, it scarcely looked like the scene of a disaster. Apart from a roofless corner of the mill exposing a skeleton of crumpled beams and the toothpick-like remains of a timber trestle which once carried the railway track to the ore bins, everything looked more or less in order. Gone were the powerhouse, the machine shop, compressor house, garage and warehouse. Everything that stood vertically or was parked on the upper bench was swept into the valley — bulldozers, shovels, trucks, they all went. Diesel generators and massive reciprocating compressors anchored to their foundations by 1.25-inch-diameter steel bolts were felled as by a cleaver. Two of the generators were found on the slopes below when spring arrived and the snow melted. It was as if the path of the avalanche had been the barrel of a gun.

Yet despite the swath of destruction, not a man was hurt. There was not a single broken bone nor a twisted ankle. The only casualty was the mine. There were refinancings, re-organizations and trial runs of the refurbished plant during a period of years, but all to no avail. In the end there was bankrupcy. But the orebody remains.

— The author is a mining engineer and freelance mining journalist in Victoria, B.C.