Fly ash in concrete: boon or bane?
| October 06, 2009
This past Sunday the television news show 60 Minutes aired a segment that alleged there may be environmental and health dangers associated with coal ash or fly ash. Fly ash is a by product of burning coal in power plants and its use in concrete admixtures has been hailed as a smart environmental solution by the Federal Highway Administration. But now the EPA, according to 60 Minutes, thinks it may need to regulate the substance.
Most of the report deals with the coal ash containment pond rupture in Kingston, Tennessee earlier this year, which was an ecological disaster downstream. But once the EPA starts regulating something, its zeal seems to know no bounds or common sense either. Fly ash has a certain level of toxicity, but the cement it replaces in concrete does too. And manufacturing cement requires huge amounts of electricity–most of which is created by burning coal.
Let’s hope the EPA in its investigations sees the fly ash recycling in concrete as the environmental success story that it is. Several other fly ash recycling strategies were mentioned in the report, but concrete roadbuilding admixtures seem by far the safest and most desirable. You certainly don’t see the EPA shouting this from the rooftops but the construction industry recycles more material by weight–asphalt and concrete roadways, demolished concrete structures and steel–than any other industry or group in the country.