Construction-and-demolition debris is like an adopted child ignored by her foster parents in favor of their own children until they notice she has the best grades, excels in sports, and is in line for a scholarship.

By John T. Aquino

Historically, construction-and-demolition (C&D) debris has not received the attention that bread-and-butter MSW has received. Data and classification have often been problems. The United States Environmental Protection Agency estimated that 136 million tons of building-related debris were generated in 1996. Of that, 20-30% was recovered for processing and recycling and 35-45% was sent to C&D landfills. The main sources of its generation were nonresidential demolition (33%), nonresidential renovation (21%), nonresidential new construction (3%), residential new construction (5%), residential demolition (15%), and residential renovation (23%). But William Turley, executive director of the Construction Materials Recycling Association (CMRA) in Lisle, IL, notes that the EPA figures do not include road and bridge debris, which CMRA estimates brings the total of C&D debris to 320 million tpy. CMRA also estimates that 25% of the North American C&D wastestream is recycled.

There is even some dispute over the number of US C&D landfills. An April 2001 study conducted by R.W. Beck for the Environmental Research and Education Foundation of Washington, DC, reported that there were 600 C&D landfills - 50 owned by publicly traded companies, 200 by private companies, and 400 by the public sector - but Biocycle magazine's April 2000 survey of the solid waste industry claimed there were 1,599 C&D landfills. "I have seen both numbers before," says Turley, "but the NADC [National Association of Demolition Contractors in Doylestown, Pennsylvania] also quotes the higher number. I think the higher one includes inert-only fills, basically just concrete, brick, and the like. Of course, many MSW fills also will take in C&D, so what does that push the number to?"

NADC Executive Director Michael Taylor notes that the association's 1994 survey showed 1,800 C&D landfills, but some of them, he says, "had an obviously finite life and have closed over time." He adds that data from C&D contractors, "like any entrepreneurs," are usually closely held, although NADC is beginning a new survey conducted by an outside firm.

State figures for C&D debris will naturally vary from state to state. In California, C&D materials accounts for almost 12% of the wastestream, according to sampling of solid waste disposed in California in 1999 in a California Integrated Waste Management Board (CIWMB) study. C&D wastestream material includes concrete, both from the foundations of homes and from highway and airport repair work; asphalt, almost exclusively from roadwork; wood, largely from building demolition and waste from new construction; gypsum, recovered from wallboard at demolition projects, left over from construction, and rejected by wallboard factories; and asphalt shingles.

South Carolina generated more than 1.1 million tons of C&D waste in 1999, also accounting for almost 12% of the total amount of its solid waste generated. In Florida, however, C&D materials represent from 25% to 33% of all the state's MSW. The Florida C&D debris wastestream comprises four major subcategories: land clearing, transportation-related, building construction and demolition, and disaster. Dimensional wood (44%), cardboard (11%), gypsum wallboard (8%), and roofing shingles (6%) account for more than two-thirds of C&D debris by volume. In 1998, Florida generated nearly 25 million tons of MSW, of which C&D debris accounted for 5.9 million tons, or nearly 25% of the total. However, not all C&D debris generated in the state is included in the term "municipal solid waste" as defined by Florida statute. Large fractions of the C&D debris stream, especially transportation-derived debris, are not counted as MSW. The total amount of C&D debris generated in the state from all sources in 1998, then, is estimated to be 9.4 million tons or 33% of all MSW.

But whatever the state variances, C&D debris is acquiring a great deal of attention. In 1996, Portland, OR, passed an ordinance requiring job-site recycling on all construction projects with value exceeding $25,000. In 1999, the Town of Atherton, located in the San Francisco Bay area of northern California, imposed ordinances for C&D recycling and diversion that require every demolition project to be available for deconstruction, salvage, and recovery prior to demolition. Owners and contractors must recycle 50% of demolition debris, including concrete and asphalt; 15% of debris other than concrete and asphalt; 50% of roofing shingles; and 50% of new construction materials. (Atherton is primarily residential, and C&D activities center on home improvements and new residential construction.) In early 2001, Massachusetts included a ban on recyclable C&D debris from landfills in its proposed Solid Waste Management Plan. And the CIWMB and Texas Natural Resources Conservation Commission both have promulgated new rules dealing with the management and permitting of C&D wastes in their respective states.

C&D debris has also drawn interest because it offers a variety of recycling opportunities. Wood can be used for fuel, wallboard can be processed into gypsum, and concrete can be used for aggregate in road-building and other construction projects. These materials, for which there are established markets, are being separated out for recycling. Organics also are being separated out of the C&D wastestream more frequently.

In response to this increased interest and activity concerning C&D waste, the Solid Waste Association of North America (SWANA, Silver Spring, MD) and CMRA have developed a C&D waste training course.

Unfortunately, part of the attention C&D debris has received of late is the result of a national tragedy: the September 11, 2001, terrorist attacks on the World Trade Center in New York City and a portion of the Pentagon. All of the industry's C&D experience was called upon in this national crisis. Soon after the attack, SWANA estimated that 1.25 million tons of demolition waste, nine times the amount of demolition waste generated in any one day in the US, would be carted away from the World Trade Center. But within six months, the actual figure had risen to 1.8 million tons, or 108,342 truckloads. Approximately 60,000 tons of steel from the World Trade Center was shipped to recyclers around the world, mostly to South Korea and certain US cities. The steel was - mundanely - to be used to make soup cans, appliances, car engines, buildings, and medallions.

Northeast contractors arrived at the World Trade Center first and contributed operators and equipment to the rescue efforts, including Yannuzzi & Sons in South Orange, NJ, and Mazzocchi Wrecking in East Hanover, NJ. Many stayed for the recovery and cleanup effort, working as subcontractors to lead contractors Turner Construction in New York, Bovis Lend Lease in London, and AMEC Inc. in London. Later, contractors from other parts of the country were brought in, including D.H. Griffin Wrecking in Greensboro, NC. All agreed that it was, emotionally and physically, an extremely difficult job. C&D recycling firm Taylor Recycling Facility LLC of Montgomery, NY, joined the effort, with its spokesmen noting that only a few companies in the US were trained and had the equipment to handle this type of work.

Waste-related manufacturers played a part too. Mack Trucks of Allentown, PA, for example, lent six  equipped with 20-ton demolition dump bodies to help with the recovery effort. The trucks were operated 24 hours a day from mid-October to March 1, 2002, and performed the equivalent of three years' service in six months.

(And now the waste-related concerns of the World Trade Center site have moved on to other areas. At the Brownfields 2002 Conference, held in Charlotte, NC, November 13-15, 2002, there was a panel that discussed whether the site should be considered a brownfield or whether that classification would offend those who consider the site hallowed ground.)

While the September 11 tragedy drew more attention to C&D debris, it has often silently been a focal point for the solid waste industry. Chaz Miller, state program manager of the Environmental Industry Associations in Washington, DC, draws attention to the use by analysts of the management of C&D debris as an indicator of the health of the solid waste industry. The rationale, Miller says, is that since the replacement side of C&D debris management is a relatively easy way to get into the industry, the number of companies entering this market has been seen as indicative of the industry's strength of weakness.

Trends

Dual-deck finger screen

New technology is a growing trend for C&D recycling, says CMRA's Turley. "Today C&D recycling techniques have really advanced. For those facilities processing mixed C&D, there are still simple dump-and-pick sites working. But all the new operations coming on-line have advanced sorting techniques that allow a more thorough separation of materials. This allows for creation of more added-value products, which is where the industry should be headed in the future in order to be more profitable.

"But currently C&D recycling is not always profitable," Turley adds, "especially in most of the middle of the country and wherever tipping fees are still low. [The] coasts are where most of the C&D recycling is taking place, with New England having the best C&D recycling infrastructure in the world, outside of Europe. It will be interesting to see how Massachusetts's ban on unprocessed C&D in landfills plays out next year when it takes effect. Will the material just travel over state lines or will this spur recycling? Interestingly, one of the big waste companies is just about finished installing a multimillion-dollar, state-of-the-art facility in the middle of Massachusetts."

Sun Recycling's Pompano Beach processing facility is one of three systems now in operation in south Florida's active C&D market. The systems were designed by Sherbrooke O.E.M. of Quebec, Canada, with vibratory classification equipment by General Kinematics Corporation in Barrington, IL. The highly automated vibratory equipment gave Sun Recycling more capacity to rapidly process increased volumes of mixed C&D waste and to economically increase the production of clean aggregate. Each system includes a vibratory classifier to help resolve a rock and shingle contamination problem.

Another issue facing C&D recyclers is franchising, Turley says, noting the filing of some Florida lawsuits over whether C&D is a solid waste, and therefore subject to a government entity's jurisdiction or is a recyclable. "We think anything you can recycle 80% to 90% or more of is not garbage, but the big waste companies owning landfills tend to disagree, as do the local governments, relying on their piece of the landfill host fee."

And, Turley concludes, as is common with all recyclables, "markets do remain difficult to develop for recycled C&D products. Recycling always will have a strike against it in many eyes because it isn't virgin materials. What is needed is more research proving the engineering characteristics of recycled products."

Portland to Duck Valley to Claremont

Magnetic separation pulleys separate ferrous material from recovered wood.

There are numerous innovative C&D programs throughout the country. After passing its ordinance in 1996, Portland went from a negligible amount of C&D recycling in 1989 to recycling 40% of its C&D waste. This increase has diverted one-third of the city's waste from landfills each year. And the effort continues. The Home Builders Association (HBA) of Metropolitan Portland and Metro Regional Environmental Management announced in September 2002 that they are joining forces to help promote recycling of construction-site debris in the area. By 2005, Metro would like to reduce the amount of construction waste by more than 50,000 tons, says Kevin Curry, HBA director of communications and public relations. The HBA will distribute a recycling toolkit that the Metro agency has put together, place regular columns in the association's newsletter, hold occasional educational meetings in the area, and provide tips and techniques to its members on how to boost recycling.

On a smaller scale, as part of the 10-ac. waste disposal complex of the Shoshone-Paiute tribes of Duck Valley in Owyhee, NV, there is a transfer station and monofill areas for scrap wood, scrap metal, and demolition debris. Marcie Phillips, the tribes' environmental director, says the C&D monofill is five years old and has diverted thousands of tons of debris. "It's one of our most successful operations," Phillips says of the quarter-acre area, "although we have to watch it really carefully to keep sheetrock and fiberglass insulation out and keep the monofill successful. Mostly it's concrete rebar-type waste, some asphalt, and some leftover concrete. We have a number of older buildings being demolished and new construction. There is a huge need to segregate C&D waste." In consolidating its waste disposal complex, the tribes have created a new C&D monofill in collaboration with a construction company client.

EPA awarded a grant to CMRA to conduct a large public education and training program to increase the reuse and recycling of C&D waste in Claremont, CA. The grant program is funded at $75,000 for one year from July 2002 through June 2003. The purpose of the grant is to implement at least seven projects throughout the US that would be model programs for diverting C&D debris from landfills and creating markets for recycled C&D materials. Under the program, participants join the EPA WasteWise Building Challenge Program; implement a corporate or local government policy to reuse and recycle C&D debris on eligible C&D projects; incorporate reuse and recycling into construction or demolition documents, including contractor requirements and specifications; include contractor or subcontractor training on best practices for reusing or recycling C&D debris; provide CMRA and EPA with C&D diversion data and project information to be included in a case study for the grant program; and incorporate a holistic sustainable design approach for the project that would include reused or salvaged materials, recycled-content products, and other sustainable design measures as applicable to the project scope.

Claremont, 20 mi. east of Los Angeles, is a small community with 10 Claremont College campuses. Claremont Village is a commercial area that includes restaurants, banking, and other small businesses in the city's central business district. The village decided to expand the downtown area, which would involve 200,000 ft.² of demolitions on 41 ac. The city is required, under California's AB 939, the Integrated Solid Waste Management Act adopted in 1989, to divert 50% of its waste from landfills as of 2000. Claremont is unusual in that it is the sole hauler for solid waste generated in the city; private haulers are not allowed to handle residential, commercial, or institutional waste within the city limits. Recyclable materials, however, can be hauled by commercial recyclers.

An initial goal of the project is to assist the city in developing a C&D reuse and recycling and diversion ordinance applicable not only to the village expansion project but also to other public works and private residential, commercial, industrial, and institutional developments within the city. This will reduce the city's work effort and help it take advantage of the most successful ordinance programs.

It is estimated that the Claremont Village expansion project will require 78,832 ft.² of building demolition on about 35 ac. Completed to date is the work at Johnny's Tree Service, 4,000 ft.²; Quonset Hut, 1,856 ft.²; Manzur property, 1,500 ft.²; and the Gottuso Property (Century 21), 3,300 ft.² As of this writing, work is in progress at the west end of the Packing House, 40,500 ft.² (13,500 per floor with three floors), and scheduled soon is the Ice House, 27,676 ft.²

In the initial results of the project, the recycling figures are very good, says CMRA's Kelly McArthur Ingalls. A September 16, 2002, report by Laird Construction Co. Inc. in Rancho Cucamonga, CA, for work on six buildings that were demolished as part of the village expansion, shows 2,016 tons generated, 1,931 to be used or recycled and 85 tons to be disposed, for a landfill diversion rate of 95.7%.

The Fall of Central

(From Top) The Claremont cold storage building, Quonset Hut, and Packing Houses are all to be demolished as part of the Claremont Village expansionproject.

But the road to C&D diversion is not always smooth. If there were ever a C&D recycling operation that captured the industry's imagination as well as that of the public, it was Central C&D Recycling in Des Moines, IA. Both Waste Age and Recycling Today featured articles on the company's vision. Central C&D's story says a great deal about the new technology available for C&D recycling and the challenge for private C&D companies.

In October 1996, a joint project of Central C&D Recycling, its parent Corell Contractors, and Artistic Waste Services Inc. was awarded a grant from Iowa's Department of Natural Resources for a demonstration project to divert 50% of C&D from landfills. A unique feature of the project was curbside collection of C&D. (Artistic's president said in 2000 that the program had become self-sufficient and was serving as a model for other Iowa communities.) Five years later, Central C&D Recycling opened a new, state-of-the-art facility in Des Moines designed to separate or produce clean products from asphalt shingles, concrete and asphalt, gypsum, metals, old corrugated containers, and wood. The plant had a 90% recycling rate at 50 tph using a combination starscreen/air separation/picking station/float tank system.

Clean gypsum, brush, and asphalt shingle waste were directed toward separate areas for processing, while the rest was placed in a corrugated metal building with a concrete floor. A wheel loader fed the sorting system, and a 4-ft., 7-in.-wide by 19-ft., 8-in.-long vibrating feeder started the material up a nearly 5-ft.-wide belt to the first sorting platform. The unders from the first starscreen fell onto a conveyor, while the overs went to a second picking line 61.5 ft. long by 3 ft., 3 in. wide. Between the picking line and the second starscreen, an air separation system removed small pieces of plastic. The secondary line fed into a float tank to separate the wood from the aggregate. Gypsum was processed and mixed along with clean wood to make an animal bedding product popular among farmers. The wood was made into chips with twin 300-hp electric grinders, and asphalt shingles are ground by a Bandit Beast grinder and put on gravel roads as a dust suppressant.

Few facilities have received more media attention. But then, in early 2002, Central C&D Recycling closed its doors, disconnected its phone, and tried to sell its used equipment. Part of the reason, those familiar with the situation say, was the competition from Metro Waste Authority, an independent government agency that serves 16 communities in Polk County that runs the area landfill - Metro Park East - and that reportedly offered a tipping-fee reduction for large volume C&D. CMRA's Turley notes that the Metro Waste Authority quickly appeared very anxious to set up its own C&D recycling plant.

Specific Material Issues

Top: Finger screen. Bottom: De-stoner

Some construction-related material has generated specific attention in recent months. Random tests conducted by the Environmental Working Group in Washington, DC, concluded that the amount of arsenic found on the surface of pressure-treated lumber used widely for decks and play sets exceeds safe levels even after years of wear. On February 12, 2002, lumber companies, in an agreement with EPA, said that after December 2003 they no longer would use chromated copper arsenate (CCA), a powerful pesticide, to protect lumber from decay and insect damage in residential settings. As part of the agreement, EPA said it did not believe there was any reason for people to replace the CCA-treated wood, which is used in an estimated 90% of such outdoor wooden structures as decks, play sets, and picnic tables. EPA is in the process of conducting its own formal risk assessment.

Turley says, "While there remain questions about how much CCA can be ingested and how it gets into the human body, it is definitely something that is in today's C&D wastestream. In 90% of the country, it is not a problem. There is very little of it, and usually it is shipped off to a landfill. Where it is more prevalent, such as Florida, the recyclers there look for it in incoming landfills and get it out of their operations because it will ruin their products. Some does still get through, but tests have shown that when that little bit gets mixed in with the thousands of tons a recycler would be processing anyway, it is below EPA tolerance levels. C&D recyclers need to remain vigilant to keep the material out of their incoming waste."

Asphalt shingles have also received new attention. Approximately 11 million tons of asphalt shingles are disposed in landfills every year. Asphalt shingle recycling is being practiced at several locations in the US, and several potential markets exist for recycled asphalt shingles, including hot mix asphalt, cold patch, dust control on rural roads, temporary roads or driveways, aggregate road base, new shingles, and even fuel.

There is an old saying about how the mills of the gods grind slowly but they grind exceedingly fine. With C&D recycling, the path might have been slower than its operators and proponents would have liked. But rather than comparing slowness with fine grinding, the saying could now be, "The mills of the C&D recycling gods grind fine, but they aren't yet as revered as they perhaps should be."

John T. Aquino is a writer and attorney based in Washington, DC, and is executive director of TASWER (Tribal Association for Solid Waste and Emergency Response).

MSW - July/August 2003