Paving the way

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In September 2022, California Gov. Gavin Newsom signed a bill designed to increase the use of recycled materials in road construction projects. Once the bill takes effect in 2024, contractors and construction and demolition (C&D) recyclers could reap the various benefits the landmark bill offers.

A.B. 2953 requires local municipalities and other agencies with jurisdiction over a street or highway—to the extent feasible—to apply standard specifications that permit the use of recycled materials in new or repaved roadways as of Jan. 1, 2024. Those materials include reclaimed asphalt pavement (RAP), recycled base and subbase materials, reclaimed aggregate and more.

“It requires local governments in California to have specifications that are as accepting or better than the [California Department of Transportation’s] specifications for recycled construction materials,” says Charley Rea, director of communications, safety and technical services for the California Construction and Industrial Materials Association (CalCIMA), headquartered in Sacramento.

CalCIMA is the state trade association for aggregate, concrete, asphalt and industrial mineral producers that provide materials for various construction projects in California. CalCIMA says it backed the bill to increase the recycling of construction materials to conserve natural resources, maximize recycling and reduce emissions.

What it does

Under the new law, cities can substitute up to 25 percent RAP for virgin aggregate in the overall aggregate blend. When 15 percent or less RAP is used, the virgin binder must be the specified grade of asphalt binder for Type A hot mix asphalt (HMA).

For RAP substitution greater than 15 percent but not exceeding 25 percent, the virgin binder must be the specified grade of asphalt binder for Type A HMA with the upper and lower temperature classification reduced by 6 degrees Celsius.

Aggregate subbases and bases can contain any combination of materials, such as broken stone, crushed gravel, natural rough-surfaced gravel, sand or processed reclaimed asphalt concrete.

“There are a lot of municipalities [in California] that have lower thresholds for the amount of recycled asphalt products that you can include in an asphalt mix,” says Senior Vice President Brian Dowd at Granite Construction, a Watsonville, California-based diversified construction and construction materials company. “The state allows a higher percentage. So, really, this is to try to get the smaller municipalities up to speed [with the rest of the state].”

Dowd adds that one of the biggest issues with using RAP in road projects, historically, has been educational.

“Some [local governments] felt like there may have been additional costs to using recycled asphalt pavement. There was also skepticism about the integrity of this mix compared with virgin materials, [including that] it may be weaker,” he says.

Dowd adds, “We have decades of evidence to show that isn’t true and that this saves money for them.”

Newsom vetoed an earlier recycled aggregate bill, A.B. 1035, in October 2021. In his letter explaining why he rejected A.B. 1035, Newsom states that requiring all local agencies with jurisdiction over streets and highways to comply with Caltrans’ recycling standards might result in increased costs. He points out that standards adopted by Caltrans are specifically designed for Caltrans projects, which generally are larger and address a greater volume of traffic than those administered by smaller municipalities.

Newsom writes that the requirements of A.B. 1035 would not have been appropriate for all local streets and roads and might create a reimbursable state mandate, which could result in significant costs for California.

However, in A.B. 2953, the adopted bill, cities with populations of 25,000 or fewer residents and counties with 100,000 or fewer residents are exempt from these requirements. The new law also does not require any city or county to use recycled materials if they are unavailable or too costly.

“Hopefully, this spurs more use of recycled materials,” Rea says. “Right now, there’s still about 600,000 tons of concrete a year that go to landfills. This will encourage cities to use recycled materials and divert some of that material away from the landfill.”

Beneficial impacts

CalCIMA says that once the law goes into effect, it will expand the recycled aggregate market in the state because more cities will be required to use RAP in road construction programs. This has the potential to place downward pressure on costs, resulting in a more competitive marketplace.

Rea adds that because RAP will be required for road projects, demand will increase in the state, enabling C&D recyclers to sell more material, requiring a boost in supply.

Additionally, the law is expected to increase the efficiency of road construction projects. Because contractors can use RAP for certain projects, they could recycle demolished roads on the spot and process the debris to use at the same site. This will lead to a decrease in material extraction costs, transportation costs and downtime.

Dowd adds that the bill’s passage should have environmental benefits as well. Because contractors can use aggregate recovered from roads, they will not need to rely as much on virgin minerals or oils that go into producing new pavement. According to CalRecycle, a branch of the California Environmental Protection Agency that oversees the state’s waste management, recycling and waste reduction programs, using recycled aggregate can save money for local governments and other purchasers, create additional business opportunities, save energy when recycling is conducted on-site, conserve diminishing resources of urban aggregates and help local governments meet the diversion goals of The Integrated Waste Management Act (A.B. 939). Passed in 1989, A.B. 939 requires all California jurisdictions to prepare a source-reduction recycling element report showing how they would divert 50 percent of their waste stream from landfill disposal by the year 2000. Later legislation mandates 50 percent diversion annually. The penalty for not reaching this goal each year can be a $10,000-per-day fine until the diversion goal is obtained.

“This is going to have a positive impact on C&D recyclers,” Rea says. “The more we can break down the barriers where this material is not allowed, it just makes it that much better understood as a viable material and expands the market.”

Overall, Dowd and Rea say this law will lead to an increase in aggregate recycling in the state. According to a statement the Chicago-based Construction & Demolition Recycling Association sent to its members, the law is the most aggressive push by a state government to use recycled materials in roads. By driving the demand side, the association says the legislation provides a better way to increase recycling rates in the long run than passing disposal bans.

“The passage of this legislation is a key component of the California construction and essential mineral producers’ efforts to reduce the carbon footprint of construction in the state by ensuring the maximum use and reuse of resources,” CalCIMA President and CEO Robert Dugan says.