Engineers have found that volcanic ash--ordinarily considered waste material-- can be used as a sustainable additive in concrete structures. A neighborhood's infrastructure can be made with considerably less energy if buildings are built with concrete that is 30 percent volcanic ash.

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Engineers have found that volcanic ash--ordinarily considered waste material-- can be used as a sustainable additive in concrete structures. A neighborhood's infrastructure can be made with considerably less energy if buildings are built with concrete that is 30 percent volcanic ash.