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February 23, 2005 | General

MIXED C&D DEBRIS RECOVERY UPDATE


BioCycle February 2005, Vol. 46, No. 2, p. 38
As more local jurisdictions in California adopt ordinances to divert construction and demolition debris from disposal, business is picking up at recycling facilities designed to process mixed loads.
Dan Emerson

FOUR years after the launch of the state’s first local construction and demolition debris recycling ordinance, cities and counties in northern California have made significant progress toward their waste diversion goals. “In general, it’s been going very well,” says Steven Bantillo, commercial program manager for the city of San Jose, the first municipality in the region to take the step.
The city instituted the Construction & Demolition Diversion Deposit Program (CDDD), an advanced diversion deposit for construction and demolition (C&D) material. It became effective in July 2001 (see “Giving A Boost To C&D Diversion,” March 2002). At the time, C&D debris represented 30 percent of the waste going into landfills in San Jose and it was determined that over 100, 000 tons/year of this stream could be recovered. All residential and nonresidential new construction, alteration and demolition projects require a CDDD Clearance and Deposit before a building permit is issued.
The other key piece of the CDDD program was having certified facilities where generators can take the C&D to be processed, and receive the necessary receipts to retrieve their deposits. Two types of certification were created – one for inert processors (e.g. handling only one type of material, such as concrete) and the other for mixed C&D processing facilities recovering at least 50 percent of the incoming C&D. Facilities handling mixed C&D loads are subject to a qualitative and quantitative analysis. There are 22 certified facilities (these can be viewed at www.sjrecycles.org/ business/cddd-certifiedfacilities.htm).
Since San Jose adopted its advanced deposit fee for C&D debris, other jurisdictions in the state have followed suit, not necessarily with an identical program, but in the same family. A look at a C&D recycling site managed by the California Integrated Waste Management Board (http://www.ciwmb.ca.gov/ConDemo/) shows that 12 cities and five counties have some sort of C&D Ordinance. In addition, CIWMB adopted its own Model Construction and Demolition Diversion Ordinance in March 2004. The Board was directed by the state Senate to “adopt one or more model ordinances, suitable for modification by a local agency that the local agency may adopt that will require a range of diversion rates of C&D waste materials from 50 to 75 percent, as determined by the board, and as measured by weight.” In July 2004, CIWMB sponsored a workshop on C&D ordinances. (Presentations from the workshop can be downloaded from the website just provided.)
The remainder of this article updates mixed C&D recycling projects in northern California that were written about in BioCycle over the past several years. Articles are available through the BioCycle article archives (www.biocycle.net; downloads are free to subscribers for articles published in November 2003 and forward).
SAN JOSE UPDATE
One major change in the San Jose C&D recycling program has been the addition of roofing materials to the system, according to Steven Bantillo. “That was planned from the beginning; it just took a while to put all of the systems in place.” With a $100 flat rate for roofing material tipping, “that increased our workload tremendously. We’re looking at that issue now from an administrative perspective – are we really gaining from having it in the system? It didn’t come out in our initial conversations with the roofing industry, but by and large, they are not in the business of transporting materials. They don’t do long hauls on roofing debris, so 99 percent of the materials generated go to one of our facilities anyway.”
In California, markets for recycled roofing materials “haven’t really developed yet,” he adds. “You hear about people recovering shakes and asphalt shingles, but here in the San Jose market, it hasn’t grown. (Roofing) materials are staying here; they’re not being used as ‘hog’ fuel or alternative daily cover.”
Several of the certified C&D facilities were profiled in BioCycle over the past few years. Zanker Road Resource Management operates two C&D recovery facilities at two adjacent landfills. Together, they handle 1,200 tons/day of material. (See, “Advances In Sorting Mixed Loads of C&D Debris,” February 2002 for a description of the processing lines.) With its demolition-refuse recycling portion well developed, “we’re going to focus on (processing) more construction waste and self-haul material,” says Michael Gross, marketing manager at Zanker. “Material gets more difficult to process as it gets smaller, so we’re installing a sorting line – hand-sorting the larger items and taking the residuals from that and running them through sorting and screening equipment. It should be up and running in about three months. By getting more of the smaller material, we expect to increase our recycling rate by 20 to 30 percent.”
Another facility that does C&D recycling in San Jose is Guadalupe Rubbish Disposal Co., a Waste Management company. Guadalupe started with a C&D sorting operation in mid-2001 (see “Giving A Boost to C&D Diversion,” February 2002). Since December of that year, it has been using a custom-designed, semiautomated sorting and processing line designed and installed by Lubo, USA, part of the Netherlands-based manufacturer of recycling equipment. Lubo designed the $600,000 system to fit within Guadalupe’s 20,000-square foot steel building. It’s designed to process more than 200 tons/day of C&D waste.
The system was designed with flexibility to be easily reconfigured, “depending on the end markets for the material,” according to Chris Simon, Lubo’s western sales manager. “They can move people around. If they are going after cardboard and wood, for example, they might use only four people. To go after brass and copper, they would use more people.” The automated systems use more sophisticated feeding and screening systems, along with features like compressed air to remove light material “no one can pick, like Styrofoam,” and flotation tanks to separate light and heavy material.
To date, the 115-acre facility has been processing up to 250 tons/day, according to Alex Gabel, recycling operations manager. Its C&D recycling rate has been about 72 percent, and 92 percent if alternative daily cover is included. While the system has worked well, the biggest challenge in recycling C&D has been “getting clean material in order to have marketable products, because it’s a mixed waste stream,” Gabel says.
To produce marketable product, one useful component of Guadalupe’s system has been the Diamond Z 1460 BL tub grinder used to process waste wood into mulch and compost. The facility recovered and processed about 7,000 tons of wood in 2004. Finished product is sold to private contractors and self-serve customers.
To process recovered concrete, Guadalupe uses a local subcontractor, Elon Inc. “They were here for about two months recently, and they’ll be back in the spring,” he says.
In recycling C&D, Gabel notes the most common form of contamination is plastic and paper mixed in with the waste wood. “Most places take everything else out and let the wood go; but we do a ‘positive’ sort for wood, picking the clean wood and dropping it in boxes.” A certain amount of treated wood gets into the stream, “but we have trained our sorters not to put it into the material being processed.”
ALAMEDA COUNTY
Alameda County has a voter-approved waste diversion goal of 75 percent by 2010, 25 percent higher than the state-mandated goal of 50 percent. Since the county’s C&D recycling regulations took effect, “there haven’t been any real hiccups; the contractors seem to have adjusted pretty well,” says Tom Padia, recycling director for the Alameda County Waste Management Authority. With assistance from county waste management staff, most of the cities in the county have adopted C&D diversion ordinances requiring contractors to submit waste management plans showing how they will divert from landfills at least half of the C &D debris they generate, and submit documentation – in the form of scale tags or receipts.
Regarding markets, Padia adds, “in the last year or so we have had some intermittent reports that some contractors were having problems unloading concrete. Because of the sad state of government budgets, there has been deferment of road projects and capital projects. So the demand for aggregate dropped to the point where some recyclers can’t accept new materials until they are able to move their processed material inventories.” In some cases, processors have “gotten temporarily choked up with inventory and can’t accept loads. The contractors have to come back a couple of days later.”
On the positive side, “recovered wood has continued to move, primarily thanks to the fuel markets – cogeneration plants in the Central Valley.” Finding markets for recycled drywall material “hasn’t been a huge problem, but the markets in our area are not mature, yet,” Padia notes. Outlets developed for drywall include composting facilities, where it is blended with compost for soil amendments; and incorporation into building pads at solid waste facilities. Some of the clean drywall material that comes from new construction goes back to drywall manufacturers.
Alameda County’s major C&D recycling facility is the Davis Street Transfer Station (DSTS) in San Leandro. Owned by Waste management, Inc., DSTS was a traditional solid waste transfer station that evolved into a 53-acre recycling park. (See “Materials Recovery Facility Taps Recyclable-Rich Loads,” February 2003.) The facility includes a 500 tons/day organics processing line handling yard trimmings, wood and food residuals, a 400 tons/day sorting facility for curbside and commercial recyclables and electronic scrap, and a garden center that sells compost, mulch, soils and recycled plastic lumber products.
The 350 tons/day “dusty MRF” is designed to process recyclable-rich loads of dry waste from self-haulers and Waste Management’s permanent commercial rolloff accounts, and mixed loads of C&D debris. The 31,000 square foot facility, which came on line in August 2002, is now recovering 55 percent of the incoming flow, according to facility manager David Krueger.
In encouraging the practice of C&D recycling, “the big overall issue is that disposal is cheaper than recycling,” Krueger says. “We deal with that by setting mandates and providing government subsidies. People wouldn’t come to us if they weren’t required to. That situation changes depending where you are in the country and what local disposal costs are.” In recent months, Davis Street has increased its gate rate for “casual” customers to $86/ton. The discounted rate for large-volume customers “has stayed about the same.” Under the public-private venture, Waste Management receives underwriting assistance at the rate of $15/ton recycled from the Alameda County Waste Management Authority.
While the facility’s processing equipment “has held up pretty well, a big issue for us has been dust control,” Krueger explains. “We’ve been trying to find a balance between too little and too much water. Too much water causes mud that sticks to the equipment. There are some new high-pressure, low-water-usage misting systems out there. We’re trying to find the right system.”
SAN FRANCISCO
Meanwhile, to progress toward a goal of 75 percent diversion by 2010 and “zero waste” by 2020 (see accompanying article in this section), San Francisco officials hope to follow in the footsteps of other cities by introducing a mandatory C&D recycling ordinance next summer, according to Jack Macy, commercial recycling manager. One major development in San Francisco has been the expansion of the SF Recycling & Disposal, Inc. solid waste facility (owned by Norcal Waste Systems, Inc.) from a single, outdoor C&D sorting line to an upgraded, double sorting line, with twice as much processing capacity (see “Mixed C&D Recycling On-Line In San Francisco,” February 2004).
As material flows continue to increase, “we feel we have good infrastructure and C&D sorting capacity in the Bay Area. It’s just a matter of getting the contractors and haulers to do the right thing,” says Macy. Total solid waste generation (2002 data) was 1.88 million tons; more than 600,000 tons were C&D material. “We had a few large demolition projects that made significant contributions,” he adds. “The demolition of Letterman Hospital in the Presidio resulted in the diversion of more than 100,000 tons from that project. The figures for 2003 may be down somewhat, because we had few large projects.” The city was still waiting for its 2003 data, as of late January.
FUTURE DIRECTIONS
Based on a generally successful C&D recycling experience in the Bay Area, Waste Management Inc. and Recycle America Alliance, LLC officials are considering the possibility of establishing similar operations in Sacramento and southern California, according to Joel Corona, recycling manager for the northern California and Nevada market area. “We’re looking at other C&D operations to complement transfer stations as well as landfills and individual materials recovery facilities,” Corona says. Whether the company decides to invest in C&D recycling projects in those areas will be based on perceived customer demand, potential profitability, and diversion opportunities.
The company is pleased with the progress made so far in developing markets for recycled C&D material in northern California, Corona adds. “The markets have been emerging, with the economy picking up. We’ve had good fortune in developing those markets with users, and we expect them to continue to grow. The state of California and local governments have done a good job of encouraging diversion. They’ve tried to put incentives in the right place to help develop sustainable recycling activities.”
One positive aspect of the model being used in local jurisdictions such as San Jose and Alameda County is that the materials are being reused in the same markets that produce them, he points out. “That helps develop those activities in a sustainable way, which is important.”
The cost of processing material and the need to continue developing markets represent the two major challenges for those hoping C&D recycling will continue becoming a self-sustaining enterprise activity, Corona says. While cogeneration plants still represent the most mature, consistent market for recycled wood, “we’ve also been successful developing markets for mulch and compost in landscaping and agriculture. We’ve dealt with both wholesalers and some smaller, self-serve customers, as well as landscape maintenance companies.”


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