evaluated and approved coal ash for use in cement and wallboard. Products in the EPA’s health analysis included fly ash pulled from the exhaust of coal plants by scrubbers or baghouses, according to the agency. The decision came to disprove Mr. Adams cited a 2015, ACAAthe reputation of coal combustion residcommissioned, study by the American Road uals of being not entirely clean materi& Transportation Builders Association, als. Coal ash contains arsenic, mercury, confirming ample CCP supplies for lead, and over a dozen other heavy metbeneficial use in the future. “Coal will continue to account for a significant However, the recycling was not free of als, many of which can be toxic. But the percentage of U.S. electric generation during concerns, that peaked in 2014, when a EPA said that its evaluation concluded the next two decades. […] Even under spill spewed tons of coal ash into a North that the beneficial use of coal ash in cement and wallboard is safe alternative scenarios of and applicable because accelerated coal-fueled The beneficial use of coal ash in cement and CCRs are similar to virgin electric generating materials and below the unit retirements, CCP wallboard is safe, as the material is below agency’s health and enviproduction is still EPA’s health and environmental benchmarks ronmental benchmarks. expected to exceed overall demand,” study Carolina river. The coal ash poured out of This was great news for companies that authors conclude. a broken pipe into the Dan River, turning use the material. Coal ash recycling EPA: Coal Ash, not a hazardous water into dark muck. Coal ash can have could reduce the number and use of coaldetrimental affects on air and water due ash ponds (and coal-ash spills), as well as waste There are many good reasons to view to its chemical composition, yet experts encourage and promote sustainability by coal combustion products as a resource, have indicated that, not unlike most saving resources, lessening environmental rather than a waste. Recycling them chemicals, any risks can be mitigated by impacts, and reducing costs. conserves natural resources and saves following proper disposal techniques. energy. In many cases, products made During the same year, the US Environ- The EPA decision may have encouraged with CCPs perform better than products mental Protection Agency (EPA) ruled producers to find ways to recycle coal ash, made without it. For instance, coal that they will not regulate coal ash as a leading to the record 52 percent of the fly ash makes concrete stronger and hazardous waste. As a result the agency product being reused in 2015. industry is taking significant strides in developing strategies and technologies for reclaiming coal ash materials that were previously disposed.”
more durable. It also reduces the need to manufacture cement, resulting in significant reductions in greenhouse gas emissions – about 15 million tons in 2015 alone. Major uses of coal combustion products include concrete, gypsum wallboard, blasting grit, roofing granules, and a variety of geotechnical and agricultural applications.
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OCTOBER August //September November 2016
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