A recent study conducted by the American Road & Transportation Builders Association – Transportation Development Foundation (ARTBA-TDF) warns that proposed Environmental Protection Agency restrictions aimed at removing fly ash as an ingredient in concrete could add $104 billion to the cost of the nation’s new roads, runway pavements and bridges over the next 20 years.
Fly ash is a byproduct of coal combustion for electricity generation. It is widely used as a supplementary material in the production of concrete and, in
fact, is required as a supplement in concrete used for the construction of roadways by both the Colorado and Wyoming Departments of Transportation,
according to Steve Powell, Tri-State’s senior fuels engineer. “Adding fly ash to concrete strengthens it for longer life and also reduces the tendency for the cement to crack during periods of freezing and thawing,” he explained.
The coal-burning byproduct also has been praised for its environmental benefits as a “green” building material, putting to use an energy production
byproduct that reduces demand for carbon-intensive Portland cement, requires less water in the setting process and would otherwise end up in a landfill.
Despite its many documented advantages and widespread use, new proposed disposal regulations may limit or eliminate the availability of fly ash. The
ARTBA-TDF study was conducted to forecast the potential economic impacts of the loss of fly ash availability in just one U.S. construction market –
“Without the availability of fly ash, American taxpayers would ultimately bear the burden, either paying more for the same level of transportation
improvements or dealing with the consequences of a scaled back improvement program,” said Alison Premo Black, senior economist for the ARTBA.
Tri-State contracts with two outside companies to sell a portion of its fly ash produced at Craig Station’s Units 1 and 2 in northwest Colorado and at Escalante Station, near Prewitt, N.M. The Tri-State fly ash has been used in many construction projects throughout the region, including the runways for Spaceport America in southern New Mexico.
“At our plants we produce a ‘class f’ fly ash, which is well suited for the concrete industry,” said Powell. “Selling the fly ash offers Tri-State a double benefit. We receive payments for the fly ash we sell to help offset our plant production costs and we reduce the cost of the expenses we incur for transporting it to the landfill.”
In 2010, Tri-State sold 96,000 tons of fly ash from Craig Station to an outside firm and received more than $800,000 in sales for this useful concrete additive.