Are we ready for RAP?

The use of reclaimed asphalt pavement (RAP) has been around for quite some time. According to the Federal Highway Administration (FHA), the oil shortage of the 1970s gave rise to the use of RAP in hot-mix asphalt.

As is often the case, economic factors originally led to the use of RAP and caused a reemergence in its use in the late 2000s as binder costs increased and aggregate supplies diminished, according to the FHA.

Since then, states have begun developing regulations to govern the use of RAP in roadways, creating a patchwork that presents challenges to any company doing business across state lines or in different regions of the country.

Some variety in the regulations concerning the use of RAP seems sensible. Weather conditions can vary in ways that affect the performance of asphalt products, and the volume and weight of the traffic also could vary from place to place. However, the patchwork of regulations remains a barrier to the widespread implementation of RAP around the country.

Traffic and weather conditions probably don’t vary greatly between New York City and Boston enough to make a practical difference in asphalt performance, but the regulations pertaining to RAP differ in those two cities.

Green Asphalt, which is located in Long Island City, Queens, New York, has had the good fortune to work with New York City, which permits the use of 100 percent RAP in its roads. For more details, read “100 percent RAP ready,” which discusses the company’s development of 100 percent RAP.

Green Asphalt also is working with other RAP producers outside of New York to increase the percentage of RAP permitted in roadways, but differing laws and testing standards have presented challenges for the company.

Fortunately, others, such as the National Asphalt Pavement Association (NAPA), Maryland, are shepherding the industry toward net-zero emissions pavement through its “The Road Forward” initiative.

While Green Asphalt’s and NAPA’s work is encouraging, the road ahead for RAP is long.

New York and some West Coast states, such as California and Oregon, are the most progressive when it comes to using RAP, Green Asphalt Chief Marketing Officer Kerianne Melillo says. But in many cases, she says, Green Asphalt and others trying to prove the efficacy of RAP are caught in what she calls a “Catch-22.” Melillo says recent research on the performance of virgin asphalt is scant and providing longitudinal data for 100 percent RAP, which is not widely permitted, is difficult.

Hopefully, more agencies will begin permitting pilot projects in time that could enable Green Asphalt and NAPA to accrue data to present to other agencies to help expand the use of 100 percent RAP.

CORRECTION: In the May-June issue of Construction & Demolition Recycling, we received incorrect first-quarter pricing for wood scrap. We previously stated this year’s Q1 price was $34 per ton. The correct price was $46 per ton.