2002 high angle wide shot piles of gravel at lotschberg tunnel construction site with machinery in background/ mitholtz, switzerland - 礦坑 個影片檔及 b 捲影像00:26
the us, which depends on coal for more than half of itõs electricity use, is looking to so-called 'clean coal technologies' to lower coalõs carbon... - 礦坑 個影片檔及 b 捲影像02:08
the us, which depends on coal for more than half of itõs electricity use, is looking to so-called 'clean coal technologies' to lower coalõs carbon... - 礦坑 個影片檔及 b 捲影像02:36
medium shot two coal miners with lighted helmets in mine/ miner turning and pointing something out to other miner/ audio - 礦坑 個影片檔及 b 捲影像00:04
workers in helmets, goggles, and protective clothing drill a hole into an area of solidified sulphur / hand holds stick of explosive material next to... - 礦坑 個影片檔及 b 捲影像01:03