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→适宜条件
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! width="50%" style="background:#efefef;" | Advantages优势! style="background:#f0f8ff;" | Disadvantages劣势
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| valign="top" | - Vonder rig ensures a straight borehole能保证垂直钻井<br>| valign="top" | - Tools for vonder rig are more expensive than conventional hand augering tools使用的工具比传统的手钻工具更贵<br>- Slow compared with other methods 比其他方法更慢 <br>
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===Construction, operations and maintenance===
