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1963年,在西伯利亚地区部分地用钻进水平孔代替了掘进价值昂贵的地下坑道。半年来在坑道内共钻进六个长水平孔,总长度1266．7米。钻孔最大长度272．4米,平均211．1米。
In 1963, some of the boreholes were drilled in Siberia to replace the expensive underground tunnels. In the past six months, a total of six long horizontal holes were drilled in the tunnel with a total length of 1266.7 meters. The maximum length of drilling 272.4 meters, an average of 211.1 meters.