Use of cooler, less-smelly asphalt lags on Long Island, across state

A cooler asphalt mix could extend Long Island's paving season late into fall, is more environmentally friendly and is healthier for paving crews than the smelly hot-mix type now in use, experts say.

But there's a bump in the road.

The use of the less-noxious blend -- called warm mix because it uses foam or chemicals to bind the material at up to 120 degrees lower than the intense heat required for traditional hot-asphalt mixes -- is rapidly increasing across the country, according to industry statistics. But New York and its paving jurisdictions, including Long Island, lag far behind most other states, figures show.

"There is no technical reason not to take advantage of warm mix," said Herbert Cooper of Woodbury, a chemical engineer and consultant who has paving industry clients. "It's good for the environment. It extends the paving season. Given all that, my conclusion is that we have inertia. Going to it is not a big deal."

That paving season varies by region, and by how quickly winter weather sets in during any given year.

Larry Galehouse, director of the National Center for Pavement Preservation at Michigan State University, agreed that "people don't want to get out and try something new. It's a little of that . . . Change is hard in that industry."

"The contractors have not really figured out the best way to go," Galehouse said. "There is a financial cost for additives. It could be some of the contractors don't want to pay the additional money . . . It's probably a little bit of everything."

"With the drive toward reducing carbon emissions, there's going to be more and more of a direction toward warm mix," Galehouse said.

Reduced fuel costs

Additives increase the cost of warm mix by about $5 per ton, according to a Long Island asphalt industry expert who declined to be identified. However, he conceded that was partially or fully offset by reduced fuel costs to heat the mix.

The Federal Highway Administration estimates that in the next three to five years, the warm mix will account for 75 percent of all asphalt production, which includes paving and other uses, such as roof shingles.

In Kansas, producers reported that 92 percent of the asphalt they supplied for state Department of Transportation projects was warm mix -- the highest percentage of any state.

Officials there said they have moved aggressively to get contractors to use warm mix, in part by offering contractual rewards for getting better compaction rates, basically a more dense pavement.

"When [warm mix] gained attention at the national level, the Kansas Department of Transportation went to the contractors and began talking to them," Rick Kreider, chief of the Bureau of Research at Kansas DOT, said in an interview.

"They were able to show it got them better compaction . . . ," Kreider said. While the chemicals used in warm mix are "not cheap" Kreider said, contractors found the cost was offset by the higher payments for compaction rates.

The federal government began prodding state DOTs in 2010 to rewrite their procedures to encourage the use of warm mix, the Federal Highway Administration said in an email.

The Federal Highway Administration said in a report on its website last year that "both at the production plant and on the construction site, workers inhale far less smoke and dust. This reduction is particularly important in tunnels, where ventilation is reduced."

The FHA report said the first reaction from work crews was, "There's no smoke."

The AAA said the pungent odor of traditional hot asphalt draws few, if any, complaints from motorists. "I think our members would be happy to smell anything because it would mean the roads are being paved," AAA regional spokesman Robert Sinclair said.

Warm mix also "has equal or better performance" compared with hot mix, the federal agency said. U.S. Secretary of Transportation Anthony Foxx has joked publicly that when it comes to warm-mix asphalt, it's "what my staff knows as my favorite subject."

Feds cannot mandate use

But a spokesman for Foxx said the federal government does not have the authority to mandate that states or localities use it.

In New York State, producers reported that 24 percent of the asphalt they supplied to the state DOT was warm mix. That put New York behind at least a dozen states with higher usage, including Idaho at 61 percent, Arkansas at 55 percent and Mississippi at 80 percent.

New York State officials offered no explanation for the rate of usage. "On most projects, the contractor makes the final decision on which materials to use based on the specifics of the project," DOT spokesman Beau Duffy said in an email.

But "cost is a major factor in that decision; asphalt suppliers need to invest in additional equipment and additives to make the warm mix. NYSDOT has encouraged contractors to use warm mix where appropriate through a series of pilot projects across the state," Duffy said.

After successful trials, including in Lindenhurst in Suffolk County and East Hills in Nassau, the state in 2012 decided to allow use of warm mix, Duffy said.

The New York Construction Materials Association said northeastern states generally lagged behind southeastern states in converting to warm mix, although the warm mix has greater benefits for northern climates because it can be used when temperatures are lower.

"It really is regional-specific," Bruce Barkevich, vice president of the group, said in an interview.

"Producers favor warm mix for a number of reasons -- compaction, lower temperature and other benefits," Barkevich said. "If a state is pushing, then no question, the producers will follow . . . Industry brought the technology in, government has adopted it."

Warm-mix production up

The Federal Highway Administration estimates that the reduction in fuel caused by lower heating for warm mix reduced carbon monoxide emissions nationwide by 2 million tons in 2013, the equivalent of taking 200,000 vehicles off the road.

Hot-mix asphalt is mixed at 300 to 350 degrees Fahrenheit, but warm mix is mixed anywhere from 30 to 120 degrees lower. Water boils at 212 degrees.

Asphalt plants churned out 106.4 million tons of warm mix in 2013, up sharply from the 16.7 million tons produced in 2009 when the industry began to track production, according to a report in October from the National Asphalt Pavement Association. Warm mix accounted for 30 percent of asphalt production in 2013, up from 4.7 percent in 2009, the group said.

While the bulk of all asphalt products goes to private industry, government agencies have been the driving force behind the use of warm mix. The asphalt group said 37.3 percent of mixes produced for state transportation agencies' DOTs are warm mix and 32.4 percent of mixes produced for other agencies are warm mix -- but only 25.9 percent of mixes produced for the commercial and residential market are warm mix.

Despite the industry enthusiasm and growing usage, the environmental benefits of warm-mix asphalt have not drawn much attention from outsiders. Several local and national environmental groups contacted by Newsday declined to comment, saying they were unfamiliar with the benefits of the product.

The asphalt industry conceded it has not done a good job of public education on the environmental benefits. "Unfortunately, this is an area where we need to do more outreach and education . . . ," T. Carter Ross, a spokesman for the National Asphalt Pavement Association, said in an email.