The inspectors took control of company phone lines at two of the mines to ensure that mine foremen were not tipped off about the presence of inspectors above ground.

视察员已控制两个矿井的公司电话线，以确保矿井工头得不到井上检查人员活动的信息。

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The geophysicists went on to conduct a second test in an abandoned copper mine in Arizona, using 25 iron plates spaced at various intervals in tunnels up to 45 metres below ground.

地球物理学家又在亚利桑那州一个废弃的铜矿矿井进行了第二次试验，他们将25块铁板有间隔的放置在地下45米出的坑道中。

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The barren landscape of an open-cast mine is unlikely ground to nurture green shoots, but most analysts and industry insiders reckon that they can see plenty.

露天采矿业的惨淡景象似乎不大可能出现经济复苏的征兆，但大多数分析师及业内人士均认为其前途不可限量。

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The deepest part of the mine is nearly two thousand five hundred meters below ground.

VOA: special.2009.07.21

Interestingly, we saw a very similar sentiment set-up in September-October 2009, when we wrote A Gold Mine is a Hole in the Ground with a Liar on Top.

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The multinational digger has just confirmed it has let the trucks roam free at the Nammuldi iron ore mine, a hole in the ground located in more or less the middle of nowhere, as the nearest town, Tom Price, is 60km away.

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Another challenge, Denbow said, is that when companies find higher ore-grade deposits, they are often far under the ground, making them more difficult and more dangerous to mine.

FORBES: USAGX's Denbow: Gold-Mining Companies Face Challenges Finding New Supply