Coal ash is known to contain dangerous elements including arsenic, lead, and selenium, yet the TVA refused at first to issue any health warnings about contamination from the spill.

煤灰渣含有多种危险物质，包括砷、铅、硒等，然而田纳西流域管理局起先矢口否认煤灰渣中含有对健康有害的物质。

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Vitrification is the safest disposal method at present. Howevee, some harmful substance volatilized from fly ash in melting process, which caused second contamination.

熔融固化处理是安全的处理方法，但飞灰熔融过程中有有害物质挥发，造成二次污染。

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Deposing of fly ash is in a great degree connected with development of high salinity mine drainage water, at the same time it decreases the contamination load carried away to the surface waters.

大规模的粉煤灰的充填会产生高碱性的矿山废水，与此同时，它也减少流向地表水系的废水中的污染负荷。

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