We have no meanings for "when underground" in our records yet.
1 Open-pit mining is expected to cease in 2015, when underground mining will begin.
2 Nish could feel his claustrophobia, never far away when underground , rising like a skyrocket.
3 Prohibition brought with it the Roaring Twenties, a time when underground parties and bootlegging gangsters ruled.
4 The accident occurred in Xiangtan County in Hunan province, the official Xinhua news agency said, when underground cables caught fire.
5 Sinkholes occur when underground spaces or caverns become so large they can no longer support the land above them, causing a collapse.
6 In a smart move, Apple surveyed the layout of major stations, which will give users a helpful lay of the land when underground .
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