The spectacular
growth in
organics recovery
in the 1990s has
laid a foundation
for diverting
more materials in
the MSW and
commercial
waste streams.
AS program managers throughout the United States seek to continue increasing the rate of recovery from the waste stream, organic materials - wood, food residuals as well as yard trimmings - are targeted. At 28 to 30 percent of the MSW stream, those materials represents the largest fraction except for paper (which is 38 percent). In some industries, such as lumber, furniture and food processing, organics comprise 95 percent or more of the residuals.
State disposal bans were effective in kick starting many yard trimmings composting programs. New Jersey was the first state to initiate a ban in 1987, but that early model was confined to leaves. Connecticut and Pennsylvania followed New Jersey's lead, leaving it to midwestern states such as Illinois and Minnesota to pioneer bans on a wider spectrum of yard trimmings. To date, no state has disposal bans on organics other than yard trimmings (e.g. on food waste or wood).
BUILDING BLOCK
Last year, New Jersey estimated that 1,447,000 tons of yard trimmings were recovered - most of what's available. About 90 percent of that total was composted at 171 facilities.
New Jersey isn't the only state to put up those kinds of numbers. Our State of Garbage in America survey found another six (Florida, Maryland, North Carolina, Oregon, South Dakota and Wisconsin) that recovered 50 percent or more of their yard trimmings. North Carolina estimates that it recovered just under 700,000 tons in fiscal year 1996-97, 90 percent of what's available. A short three years before, only about 300,000 tons were recovered in North Carolina.
Prior to South Carolina initiating a ban on the disposal of yard trimmings in 1993, there were 26 yard trimmings composting sites in the state. The year after the ban, the number had more than doubled to 58. And as of 1998, there were 96 operating yard trimming sites in South Carolina which processed more than 220,000 tons of material.
Even though South Carolina has come to rely more and more on composting to handle yard trimmings, there is clearly room for expansion in that state. The 220,000 tons composted last year represent only about a quarter of the available yard trimmings in the state. Still, that tonnage represented more recovered material than any other recyclable in the MSW stream, except paper. Many other states are in the same position.
The South Carolina Department of Health recognizes that more can be done with composting. In its 1998 Solid Waste Management Plan, the department noted that "centralized composting is fairly undeveloped in South Carolina with only a few counties collecting, grinding and marketing a finished compost product and a few counties shredding and offering mulch. Recycling this waste (food and yard trimmings) through composting can have a significant impact on reducing the amount of waste that needs to be handled."
EVOLUTIONARY STEPS
A state that has gone through the evolutionary steps involved with handling yard trimmings is Maryland. "Prior to 1991, there was very little composting going on," says Lori Scozzafava, who heads the recycling office at the Maryland Department of the Environment. She notes that the "little" that was occurring was typically smaller, municipal operations. But that's no longer the case. In 1997, just under 300,000 tons of yard trimmings were composted, an amount that the Department of the Environment estimates to be well over 50 percent of the total available. "There has been a dramatic increase in organics recovery," she notes.
In addition to more activity, Scozzafava points out that there has been an increase in sophistication and the types of materials processed "The facilities that only handled leaves have become projects that now also handle grass. Plus they now have wood chipping operations as well," she adds.
Most yard trimmings composting facilities in Maryland are run by the public sector. That's true in many other states as well. The vast majority of North Carolina's yard trimmings composting sites are publicly run, a situation that causes some concern for Craig Coker, who was recently hired by the state Department of Energy and Natural Resources to bolster organics recovery. "Municipalities giving away mulch and compost are a deterrent to private firms interested in getting in the business," he says.
One state that bucks the trend toward public yard trimmings sites is Oregon, where about 65 percent of the total greenwaste generated is composted. "We have a few public sites," says Lauren Ettlin, Compost Project Coordinator for Oregon's Department of Environmental Quality. "Most composting is done by private companies. Many of them started as something else (firewood processor, etc) and worked into composting. Most are fairly small operations handling anywhere from 7,000 to 20,000 tons a year."
WOOD IS WONDERFUL
Most organics recovery activities typically have started with yard trimmings, but the search for higher diversion rates has targeted other organics. One principal feedstock is wood. Although wood (seven percent) is only about half as prevalent as yard trimmings (15 percent) in the municipal waste stream, other sources of wood in many areas are significant. A recent survey in North Carolina found that an estimated 4.5 million tons were generated by wood products manufacturers.
Of the 240,000 tons of wood recovered in South Carolina in 1998, almost 100,000 tons came from construction and demolition (C & D) debris recycling operations. The other major source was the industrial sector. More than 130,000 tons were wood packaging recovered from the state's industries.
Not only is there a lot of wood available for the taking, but it also has a variety of uses - from mulch and animal bedding to building products and boiler fuel. If one market isn't available, another often can accommodate the wood. Those options have been dramatically played out on the West Coast over the past few years. In the early 1990s, energy recovery plants were a substantial market for wood in California. When that market evaporated, much of the wood residuals went into mulch, bedding and compost. In Oregon, just the opposite occurred. For several years, a fair amount of the urban wood recovered in the state went to particle board manufacturing. When that industry downscaled, wood residuals shifted into energy recovery. In spite of the shift from one market to another, Oregon still managed to recover about 236,000 tons of wood residuals in 1997.
Since wood recycling is primarily a private sector function, quantifying recovery can be a daunting task. Up until recently in New Jersey, which recovered about 471,000 tons of wood in 1997, the recovery of wood was underreported because the state was relying on figures generated by county recycling offices. The same is true in Maryland, where more than 110,000 tons of wood were recovered in 1997. Most of that was recovered by private, third-party firms. According to Virginia Lipscomb, of the Maryland recycling office, that total (which represents more than a quarter of the wood in the MSW stream) is underreported. "We have such a low number because of the way recovery figures are reported," says Lipscomb, noting that individual counties report recycling activity and often don't capture all of the private efforts. New Jersey's numbers got better when it started requiring wood processing facilities to report on their activities.
FOOD, ETC. - THE NEXT FRONTIER
While wood processing options are increasingly coming into focus, programs to extract more food residuals from the waste stream are largely still in the crawling stage. For the State of Garbage in America, New Jersey reported the highest recovery of food residuals - 297,000 tons in 1997. "The food figure is underreported," says Joe Davis, who tracks recovery numbers for the Department of Environmental Protection. "We have a lot of very aggressive pig farmers that we don't track." Davis also notes that food coming from institutions isn't all accounted for.
Maryland is another state that reported recovery of food residuals above the norm, with 147,000 tons diverted last year. Maryland's figure, like New Jersey's, includes materials such as fats and oil, as well as food processing residuals. For instance, over the years, crab chum was a disposal problem for crabbers on Maryland's Eastern Shore. Now, two firms - New Earth and Banks of Eden - are composting the chum and other organic residuals.
While most states initially directed recycling at the residential level, those initiating programs in for food residuals recovery are primarily targeting at larger generators (grocery stores, restaurants and institutions and food processing plants.)
"There's a lot of room for expansion out there," says Alan Watts of the Texas Natural Resource Conservation Commission. Last year, the commission's first ever recycling rate survey uncovered about 175,000 tons of food materials, plant and animal by-products recovery, most coming from the industrial sector. "We feel the greatest potential is at institutions such as universities, schools and prisons," adds Watts.
That same belief is held in other places as well. The City Council in Portland, Oregon recently directed the Bureau of Environmental Services to develop language for an ordinance that requires certain types of organics residuals generators, such as restaurants, to separate those residuals for recycling by July 1, 2001 (see Regional Roundup Department in this issue). Spurred on by that action, "a lot of people are talking about recovering food residuals," says Lauren Ettlin.
The next frontier for organics recovery isn't just in the food residuals field. In fact, that may prove to be secondary given the rising concern about how manure and bedding at large-scale animal feeding operations are being handled. "Attitudes about handling organics are changing," says Scozzafava. Composting and other recovery techniques are being studied as solutions to the state's disposal problem with hatchery waste. "We think composting could be a real help dealing with chicken mortalities," says Scozzafava. But of greater interest is how organics recovery techniques can be applied to manure and bedding at the poultry houses.
Concern over Pfiesteria in the waters of the Chesapeake Bay has the poultry industry searching for alternatives to land application. Recently Perdue, one of the country's largest poultry firms, announced an agreement with AgriRecycle of Springfield, Missouri to turn 120,000 tons of chicken manure and bedding into pelletized fertilizer. In addition to this and other private efforts, the state is planning to fund research into alternatives at the University of Maryland.
In North Carolina, the big concern is the manure from its mammoth swine industry. "Our next major focus will be animal waste," says Coker. "We're looking at ways to move from the traditional lagoon and spray system." The same is true of Texas, where Watts notes that pressure is building for more recovery of animal wastes.
MORE, MUCH MORE, TO COME
The decade of the 1990s has been one of spectacular growth in the organics recovery field, but in fact we just may be getting started. Of the three materials - yard trimmings, wood and food residuals --recovery of yard trimmings is probably the most advanced. Even so, on a national basis, only about one quarter of the yard trimmings in the MSW stream is recovered. As for the wood and food residuals in MSW, we've barely scratched the surface. About 15 percent of the wood - and less than five percent of the food residuals - are recovered.
In the latest State of Garbage In America survey (April, 1999), only seven states reported recovering 50 percent or more of available yard trimmings. Only three states reported that rate of recovery for wood residuals. As for food residuals, no state noted a recovery rate of more than 30 percent. There is great potential to expand all phases of organics recycling.
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