John Elkins, Granite Construction’s engineering services manager, usually crinkles his nose when he meets the smell of new asphalt being poured on a street. But with a new way of making asphalt on the horizon, he hopes the smell, and harmful environmental pollutants, will go away.

Granite Construction is adding a little moisture to the mix in its asphalt production in the hope of creating greener roads.

The company is the first in northern Nevada to spearhead “warm-mix” asphalt technology, which they claim will release fewer toxins into the environment as well as improve the quality and endurance of roadways across the state.

The U.S. Environmental Protection Agency has not issued an official stance on the technology. However, representatives said that the agency does not officially endorse any product.

Granite has used environmentally friendly mix on only one road in Reno so far. About 500 tons of asphalt was poured on Chism Street, near West Second Street, in early June as part of a testing program.

The warm mix technology Granite Construction is using creates a foaming of the asphalt by introducing a small amount of water, which means the asphalt can be produced and placed at a lower temperature. Hot-mix is usually produced at temperatures from 280º F to 340º F. Warm mix technology allows for lowering the production temperatures to between 215º F and 275º F. Reducing the production temperatures at the asphalt plant reduces the amount of fuel used, which results in an emissions decrease.

Since the asphalt is produced at a lower temperature, according to Elkins, the chemical bonds that solidify the substance break down at a slower rate. The heat that helps create traditional “hot-mix” asphalt generally fries the chemical bonds that hold the mixture together, he added.

Also, because the asphalt production process uses less heat, old, torn-up asphalt can be recycled into the mix. Elkins said that the asphalt from old roads would otherwise go to a landfill.

The third difference between warm mix and traditional hot mix asphalt could also mean longer-lasting roads, Elkins added.

“It (the asphalt) is more expandable because there is not the stiffening in the binder,” Elkins said. “There is more elasticity because you are not breaking down the binder.”

The extreme swings between Nevada’s hot summers and cold winters means that area asphalt expands and contracts wildly, Elkins said, adding that the expandable nature of the warm-mix could translate to decreased cracking in the roads.

Public works officials from the city of Sparks said they are considering putting the product down in test sections of city roads. However, Granite officials said signatures have not been put to any work contracts.

Scott Magruder, a spokesman for the Nevada Department of Transportation, said he was not aware of any warm-mix projects being completed by the department.

Representatives from the Regional Transportation Commission confirmed that they, too, are interested in greener road technology. However, according to RTC spokeswoman Felicia Archer, the commission is keeping in mind that the technology is still in its experimental stages as far as its life cycle.

Those critical of the technology claim that the same moisture that helps propel the technology forward could also break down the roads, giving it a shorter life cycle.

State regulations require than asphalt not exceed 1 percent maximum moisture content in order to avoid damage. This same moisture that makes the mix different could potentially break down the roads more quickly, according to critics.

Despite the warnings, Archer said engineering officials with the RTC are “keenly interested” in the pilot program done on Chism Street.

Elkins, said that the company hopes to make warm-mix technology the norm for asphalt production across northern Nevada in the coming years, possibly converting 90 percent of road production to the new technology.

The technology has not yet been tested for carbon emissions in northern Nevada. Such a test, according to Elkins, would require running the plant with the new technology for more than six hours. So far, the company has not had a project that would require that amount of production time.

However, some in-house tests have been performed by Granite. According to Elkins, an emissions sensor was placed near a small amount of the mix during a trial and the readings were almost non-existent.

“People will not smell fumes,” Elkins said.

As the new process simply leverages water vapor technology, the new way of producing road materials should not cost any more to cities and counties than the traditional mix, Elkins said.

According to Elkins, warm mix generally achieves a moisture level of 3/10 of 1 percent.

Granite representatives said the company uses about 1.5 million gallons of burner fuel every year — a number that they hope to reduce.

Granite began producing the technology four months ago.