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Old 26-01-2022, 04:20 PM
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Coquet Coquet is offline
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The shafts, which were 1.22m diameter, were cut by the raised boring method. A pilot hole is drilled down to the workings, then miners underground attach a shaft diameter bit to the end of drill rod; this is then pulled up to the surface to cut the shaft. All the cut rock waste falling down the shaft and is cleared away underground.
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