Underground Coal Fires

　　Coal burning deep underground in China, India and Indonesia is threatening the environment and human life, scientists have warned, these large-scale underground (51) blazes cause the ground temperature to heat up and kill surrounding vegetation, produce greenhouse gases and can even (52) ignite (点燃) forest first, a panel of scientists told the annual meeting of the American Association For the Advancement of Science in Denver. The resulting release (53) of poisonous elements like arsenic and mercury can also pollute local water sources and soils, they warned.

　　 “Coal fires are a global catastrophe,” said Associate Professor Glenn Stracher of East Georgia College in Swainsboro, USA, But surprisingly (54) few people know about them.

　　Coal can heat up on its own, and eventually catch fire and burn, if there is a continuous oxygen supply. The heat produced is not cause to disappear (55) and, under the right combinations of sunlight and oxygen, can trigger spontaneous (白发的) catching fire and burning. This can occur underground, in coal stockpiles, abandoned mines or even as coal is transported. Such (56) fires in China consume up to 200 million tons of coal per year, delegates were told. In comparison (57), the U.S. economy consumes about one billion tons of coal annually, said Stracher, whose (58) analysis of the likely impact of coal fires has been accepted for publication in the International Journal of Coal Ecology. Once (59) underway, coal fires can burn for decades, even centuries. In the process, they release large volumes (60) of greenhouse gases poisonous fumes and black particles into the atmosphere.

　　The members of the panel discussed the impact (61) these fires may be having on global and regional climate change, and agreed that the underground nature of the fires makes them difficult to detect (62).

　　Ultimately, the remote sensing and other techniques should allow scientists to estimate (63) how much carbon dioxide these fires are emitting. One suggested method (64) of containing the fires was presented by Gary Colaizzi, of the engineering firm Goodson, which has developed a heat-resistant grout (a thin mortar used to fill cracks and crevices), which is designed to be pumped into the coal fire to cut off (65) the oxygen supply.

　　 (出处：2014年职称英语教材理工类阅读理解　第二十四篇Underground Coal Fires – a Looming Catastrophe)