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We’ve all heard someone say of an old-timer, “He’s forgotten more than we know.” I used to think that comment was intended as a compliment, but as I get older, I’m not so sure. Maybe it wasn’t a compliment after all ... I forget. By Neal Bolton The end of the year causes many of us to pause, look back, and remember. And while the looking may bring a bit of melancholy, it’s easily offset by the anticipation of what the future holds—in a word: refinement. Throughout most of the waste disposal industry, we will see landfills clarifying their purpose and refining their operation to increase diversion of recyclable materials and make existing operations safer, more efficient, and more cost-effective. For most facilities, the goal will be to improve upon what’s already being done. But on some fronts, there will be continued research, trial, and application of new technologies for waste disposal. Taking Stock The landfill industry has changed dramatically over the past couple of decades, most dramatically after the promulgation of the EPA’s Subtitle D regulations in 1991. By requiring landfills to construct liners, monitor groundwater, and establish closure funding, landfill operators have become, by necessity, more sophisticated. The facilities they operate have also become much more complex and costly. Largely as a result of more stringent regulations and higher costs, we now have fewer landfills, and they are on average getting bigger. According to the EPA, the number of landfills in the United States dropped from 7,924 to 1,654 between 1988 and 2005—a decrease of 79%. During this same time period, the amount of waste disposed (mostly in landfills) decreased by just over 5%, from approximately 140.7 million tons to 133.3 million tons. As a result of those changes, the average landfill size has increased over the past 17 years from less than 70 tons per day to around 300 tons per day. This declining trend in landfill numbers has slowed and begun to stabilize. There will, of course, be some continued evolvement due to population growth and other demographic changes. But for the most part, the remaining facilities will continue functioning as our primary disposal option, while diversifying in response to environmental awareness and responsibility. As confirmation, one need look no further than the nearest landfill to see more diversion, more monitoring, more processing ... and more programs. Increasing fuel costs are also affecting landfills. Not only is it costing more to operate the landfill tractors, but higher fuel prices are having an even greater impact on transfer costs. This means those economic studies that favored long-haul distances to reach low-cost landfills may no longer be valid. Another issue that will continue to affect landfills is the growing concern about greenhouse gases (GHGs). Methane, carbon dioxide, and nitrous oxide are produced as waste decomposes. Without question, global concerns about GHG emissions will continue to pressure landfill operators to focus on landfill-gas control as a top priority. The decrease in the number of landfills combined with pressures from various social, economic, and environmental issues is a classic example of supply and demand. The increased demands on what landfills do and how they do it, combined with the overall decrease in the number of landfills, means one thing is certain: higher prices. Landfill disposal fees will increase, and as they do there will be even more interest in other types of disposal technologies. Now let’s look at some of those alternatives. Composting In Alberta, Canada, the City of Edmonton owns its own solid waste composting facility, the largest of its kind in North America, handling approximately 160,000–170,000 metric tons of solid waste per year. The solid waste is blended with approximately 10,000–12,000 dry metric tons of dewatered biosolids, resulting in an annual production of approximately 80,000 metric tons of compost. The construction cost of the facility has been estimated at $130,000,000. Many landfill operators who are composting greenwaste are familiar with two major issues: odor control and the ability to find a market for their end product. “These are also important issues for our facility,” says Allan Yee, compost program manager for the City of Edmonton.” A woodchip biofilter is used to effectively control odors at the Edmonton facility. Yee also suggests that marketing different types of compost products aimed at niche markets is important. He goes on to suggest that “when developing an alternative disposal system, it’s important that specific goals be established, up front. “The type of waste-collection system being used will also impact the disposal facility,” he says. “In Edmonton, the two-can collection system balances the desire for diversion (one can for recyclables) with the resident’s desire to limit collection-vehicle traffic (a second can for everything else). But,” says Yee, “although the source-separated recyclables are excluded from our wastestream, everything else comes into the composting facility.” Inbound waste passes through a large-scale MRF on its way to the compost facility to remove nonorganics from the feedstock. And, while the sorting effort at the compost facility might be reduced if an “organics only” wastestream existed, having the MRF has its benefits. Integration of different systems can improve the overall performance compared to what might be available through a single process. According to Allan, “The City of Edmonton is moving toward a gasification system that will work in conjunction with the MRF and compost facility.” Anaerobic Digestion Pyrolysis and Gasification Pyrolysis and gasification utilize temperatures in excess of 900°F and 1,400°F, respectively. Ash or else slag is produced, depending on the process. Plasma Gasification Waste to Energy As the acting solid waste manager with the City of Spokane, WA, Monica Bramble knows about the issues related to WTE. “WTE is coming into a more favorable light because of increasing energy costs,” she says. “Lots of communities are currently looking at WTE.” Built in the late 1980s at a cost of around $100 million, Spokane’s MSW incinerator burns up to 2,000 tons of waste per day. “When the incinerator was constructed, there were few long-haul options available. The city also wanted to take responsibility for handling the waste,” adds Bramble. The $98-per-ton tipping fee includes approximately $30 per ton for a bond that helped fund the construction of the incinerator and two transfer stations, as well as the closure of four landfills. Once the bond is paid off—and as competing landfill prices increase—this tipping fee will become even more attractive. People involved in the operation of alternative disposal facilities generally agree: Starting with clearly defined goals (saving landfill airspace, for example, or creating a product) greatly improves the odds of success, no matter what type of system is planned. The goals and system must be designed to work together—they must be integrated. The concept of integration is a familiar one among those who are “in the know” about alternative disposal methods. Chris Choate of San Francisco–based Norcal Waste Systems says, “Alternative disposal technologies are most practical when the waste collection system splits the wastestream into a wet (organic) and dry (non-organic) components.” Again we hear: The collection system must match the disposal system. “This is most likely to occur,” Choate explains, “where increases in population and congestion are combined with greater transfer distances to landfills.” Most disposal methods, including landfills, are doing essentially the same thing: waste decomposition. They are breaking the wastestream down to basic chemical components. In a landfill, the process may take many decades and, if uncontrolled, may produce serious side effects. In some of the alternative technologies, the process may be shortened to weeks, days, or even minutes. It is not yet clear how and when these alternative technologies can be applied to the larger portion of our wastestream. There is a lot of discussion today about European methods of waste disposal, most of which slants toward the United States trying to “catch up” with the more progressive European technologies. When discussing how well (or how poorly) the United States is doing in regard to waste management, we need to remember that different isn’t necessarily better or worse—it’s just, well ... different. Of course, there are those in the world—even in this industry—that look upon these choices as black or white, even as good or evil. They have landfills playing the bad guy, and these new technologies as our only hope to save the planet. As you might suspect, the choices are much more complex. Whether you get fired up over the thought of plasma gasification and WTE, or lean more toward the basics of traditional landfilling, it’s important that we establish some perspective. As you learn about disposal alternatives, keep sight of the fact that new technology doesn’t necessarily mean “best fit” technology. Certainly there will be an increasing number of situations where alternative disposal systems will make sense, generally in those areas where landfilling is impractical or very expensive. As responsible players in this field, we have a duty to become familiar with other disposal options. But in the long run, the task of providing a practical disposal system still comes down to a balance of what people want and what they’re willing to pay in order to get it. We’re talking economics. Landfilling We must currently provide disposal for over 133 million tons of waste each year. Various types of disposal systems are possible, but at this time, only landfills and their related infrastructure are able to practically meet our massive disposal need. We must protect human health and the environment. Most, if not all, of the disposal methods we’ve discussed can be conducted in a relatively safe manner, the key word here being relative. Some methods appear to be more attractive than others. Without delving into life-cycle analyses of the various methods, common sense tends toward a system that eliminates the potential hazards as completely and quickly as possible. Landfills end up at or near the bottom of this list. Our capabilities are limited by what we can afford—or, rather, what consumers can or will afford. In the final analysis, the system must be marketable; people must be willing to pay for it. Given the choice of landfills (lower initial cost) and alternative technology (higher initial cost), most people opt for the landfill. Permitting of any facility requires a massive investment of time and money—with no guarantee of success. Anyone who has tried to site a new landfill can attest to the difficulties. Nor are alternative disposal systems necessarily easier. While consumers may like the idea of alternative disposal, and in a few cases even be willing to pay for it, chances are they don’t want it in their backyard. The NIMBY syndrome is often impartial when it comes to waste disposal. If you’re the kind of person who likes to drink clean water and breathe pure air, don’t despair. The fact that landfills currently provide most of our disposal now does not mean the waste industry is acting irresponsibly. Quite to the contrary, most landfill operators recognize the fact that landfills are still our “best fit” right here, right now, and they’re continuing to take strides toward excellence. As an example, let’s look at air emissions. In-place waste (in landfills) can be thought of as a temporary storage system. The primary carbon components contributing to GHG are stored in the landfill and slowly released to the atmosphere as carbon dioxide and methane. But an ever-increasing number of landfills are collecting that gas and burning it to generate electricity—or in some cases, processing the gas for other uses. How effective is this effort? The California Integrated Waste Management Board estimates that 94% of the in-place waste (in California) is at landfills that have a gas-collection system. This certainly doesn’t mean that those landfills are containing all of the landfill gas they produce. There is a wide range of opinion and data regarding the actual and potential capture rate of gas, but great progress is being made to control GHG emissions from landfills. Like it or not, we are faced with the reality that landfills will continue to be our primary disposal option. Aware of that fact, enterprising landfill operators continue to improve their operations with new technology and old-fashioned hard work. With his can-do attitude, Thomas Edison created over 1,100 patented inventions, including the light bulb, the phonograph, and the motion picture machine. “Invention is 1% inspiration and 99% perspiration,” he once said. The desire that drove Edison to innovate and to improve is still evident today. Francis Coward, principal engineer for Fresno County, CA, is one example. He has for many years had responsible charge of the American Avenue Landfill. This is a regional landfill located in California’s central valley. Many of his landfill machines are equipped with an onboard GPS. For those of you who aren’t familiar with them, these cab-mounted systems utilize the GPS satellites to provide real-time survey control for the machine operators. By viewing a small screen in the machine’s cab, the operators can build any part of the landfill to grade without relying on paper drawings, survey stakes, or surveyors. Simultaneously, the machine’s location is recorded and used to update the landfill’s topography. Do these systems work? “They sure do,” says Coward. “We haven’t had surveyors onsite for two years.” The system also provides an audio and visual notification if the machine gets too close to a potential hazard, such as a methane extraction well. Coward is sold on the concept of using technology to work smart. After the successful GPS application, he began looking for other ways to use technology. Coward recently installed a Pelco video surveillance system at the landfill, featuring a total of 16 individual cameras from the Clovis, CA–based company. There are cameras throughout the landfill, including the shop and the scalehouse. There is even one mounted atop a 50-foot pole that allows an unobstructed view of active landfill area. Some of the cameras are fixed, while others are able to pan, tilt, and zoom. “I can control any camera at the landfill from the computer in my office—located 20 miles away,” Coward says. When asked if there was a practical application to the array of cameras or was it just a high-tech gadget, he quickly affirms the system’s practical benefits. “Because the cameras are digital, they are able to retain two months of filming on a single hard drive,” he says. “There are no VCR tapes to buy, inventory, label, and store. And when we need to review footage from a specific date and time, we can use our desktop computer to pull up the date, hour, minute, and second from any camera.” The landfill’s camera system is also linked directly to the scalehouse computer. When a customer pulls onto the scale, a camera records a photo of the vehicle and another of its license plate. These photos are linked to the transaction. Every single transaction now includes not only date, time, and tonnage, but also photographs identifying the vehicle. “It has virtually eliminated billing conflicts with our landfill customers,” he says. “Recently we had a situation where a customer accidentally left his wallet at the gatehouse window. The next customer stealthily removed the cash and left the wallet. A third customer saw the wallet and handed it over to the gatehouse attendant. Using the wallet ID, they were quickly able to return it to the customer. Unfortunately, the customer accused the gatehouse attendant of stealing the money. The dispute was quickly settled when we reviewed the video.” The story ended with the sheriff reviewing the footage and using it to catch the thief. “We love this system,” Coward says. “The risk-management folks love this system, and so does our law enforcement staff.” He sums up by saying, “Surprisingly, the operators also view the cameras as supportive rather than Big Brother watching. On more than one occasion, the cameras have verified that the crew is doing a good job.” So even as we continue to refine our landfill operations, we must keep an eye on alternative disposal technologies. Many progressives in the waste business who are looking hard at alternative disposal methods recognize that such systems will first be installed where the following criteria exist:
When these criteria can be met, an opportunity for an alternative disposal system exists. Currently these opportunities exist only in a few, predominately urban areas in the US and Canada. For most of the country, the landfill will continue to be the backbone of our disposal needs. Neal Bolton is a consultant specializing in landfill management.
MSW - May/June 2007
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