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December 2007

Recycling of construction and demolition debris increases

C&D recycling is a problem felt most in  North America.

Massachusetts is the only state in the union to have enacted a disposal ban on construction and demolition (C&D) debris. While similar bans in other states could help companies involved in C&D recycling, the industry itself is doing well, according to William Turley, the executive director of the Construction Materials Recycling Association (CMRA).

“I expect that C&D recycling will continue to grow,” he says. “It has been doing 10 percent per year and should continue because recycling often makes economic sense.”

Massachusetts has a statewide ban that applies to concrete, asphalt, wood, brick, and metals generated from construction and demolition activities.

“There are other states that have talked about it and there are some small states in New England, as well as California, that have considered a disposal ban,” says Turley. “Some jurisdictions in California have also considered such bans and now you see some partial bans. The City of Chicago requires that you recycle 50 percent of what is generated at a C&D site and Fresno, California has a disposal ban for Fresno County.”

Another factor in favor of recycling is that landfill operators, says Turley, would often prefer to not accept the material.

“Asphalt shingles are really heavy and dense and take up volume,” he says. “They might take some concrete because they can crush it up and use it as temporary roads in the landfill. Concrete fills up their space and they can make more money on municipal solid waste.”

While the landfills may not be pleased, they are still accepting the materials.

“They are not the ones driving recycling,” says Turley. “It’s coming more from economics – in many cases it is ­­­more profitable to recycle. We’re also being driven by LEED (Leadership in Energy and Environmental Design) projects and with its requirements to secure points, developers have to do more recycling and many governments practically require us to recycle.”

Dealing with C&D material is a North American problem. In British Columbia landfilling gypsum is banned. The provinces of Nova Scotia and Quebec are promoting shingle recycling.”

Highway construction generates a lot of material and Turley estimates that there are about 2,900 crushers currently engaged in the recycling of concrete and asphalt, and that there is a minimum of 200 automated systems to deal with mixed C&D in the United States.

The value of C&D debris is linked to state tipping fees at landfills.

“If there are low tipping fees, then you pull out the metals and maybe the concrete - - it’s more a landfill diversion, avoiding the landfill disposal cost,” says Turley. “Plus there are LEED requirements that you must recycle at a certain level. A lot of times it makes much more sense to recycle the material.”

As to how much C&D material is recycled annually, Turley says that figures are hard to come by, but does note that the CMRA estimates that at least 140 million tons of concrete are recycled annually.

When a highway or road is rebuilt, it generates concrete, asphalt and metals. While road construction is a key element of government budgets – federal, state and municipal, Turley stresses, “It often is performed without any regulation required because it is economically feasible.

“The Federal Highway Administration tries to promote it every chance they get,” he adds. “They have input on how federal highway dollars are spent, but they do not have a requirement to support it. They can’t right now because it is not legal for them to do so.”

But Turley says that incentives or regulations are not needed to ensure that recycling occurs.

“It is economically feasible to recycle the material, especially if you do so on the side of a road,” he says. “Look at the money you are saving on trucking, having to dispose of the old concrete and not having to buy new aggregate to replace it, especially for a road base product. It’s also a safety issue. You are putting fewer trucks on the road and reducing the number of potential accidents.”

Portable crushers – track-mounted and wheel-mounted – and other machinery help to do on-the-spot recycling and to make recycling operations more efficient.

“The equipment is there and we are seeing a lot of paving contractors that subcontracted that out starting to buy the machinery,” says Turley. “A lot of them are figuring out that they can do this themselves. Sometimes they haul it off to a local recycler down the street.

“The asphalt is either milled up and hauled off or put down in place for new hot mix – it started about 30 years ago and is has become very common,” he adds. He noted that as states go, New Jersey is doing a good job to promote such recycling operations, but that other states still need to be pushed to advance recycling. There is a lot of room for improvement and there are still opportunities in the road construction sector.”

Recycling material from the demolition of buildings is another kettle of fish.

“The demolition contractor gets in there and pulls as much as he can, as fast as he can – all the metals, especially the copper and sometimes the beams – whatever makes economic sense right off the bat,” says Turley. “When they are taking a building down, especially the larger ones, they will try to separate the materials as much as they can. For example, putting all the concrete on one side because they can get a cheaper tipping fee and usually those guys own their own crushers and process the materials themselves.

“They shear the metals down to a better size to secure a better price,” he said. Usually a demolition contractor is told on Wednesday that ‘I want that building down by next Thursday.’ That is a bit of an exaggeration, but building owners recognize the value of salvaged materials. With the prices of metals these day, I’ve seen demolition contractors who have paid to take down all-metal buildings and sites such as refineries.”

The majority of firms engaged in C&D recycling range from small to medium.

“There are hundreds of mom and pops and independent companies, and then you have the big road contractors, where recycling is just one segment of their business,” says Turley. “If you run a well-managed company, you should be very profitable. Of course, we are all seeing a little bit of a slowdown because of the current building and home crisis, but still I see that people are surviving.”

In terms of legislation, be it federal or state, Turley says that the industry had some fortunate luck in getting amendments put into bills, that this legislation has not been passed by Congress yet.

The CMRA, which promotes the recycling of construction and demolition materials and whose members do the actual recycling, would like to see legislation that requires governments to ensure that recycled aggregate be used for highway construction if it is economically feasible and the material meets the same engineering specifications for the job.