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Landfill Management Faces A High-Tech Future

May 1, 1994

16 Min Read
Landfill Management Faces A High-Tech Future

Derek Willis

In the north central region of Florida, the ongoing process of siting Alachua County's new municipal solid waste landfill has brought the issue of safe landfill management to the forefront.

Over the past year, state and county officials have battled with residents over the landfill's location. The issues are familiar: community safety and protection of groundwater supplies versus the need to properly dispose of the area's wastes.

Public mistrust of the role landfills play in managing America's waste has long been a central issue. But now landfill practices are being redefined, posing a new set of challenges for operators and the public.

Changing Attitudes Despite recent innovations in solid waste management, landfills remain an important method of waste disposal. The state of Florida, for example, landfills more than half of its waste. The state's Department of Environmental Protection estimates that population growth will produce 30 million tons of municipal solid waste (MSW) by 2010. Though the state emphasizes recycling, landfilling remains the primary method of waste disposal.

While recycling programs, along with pollution prevention and waste minimization plans, reduce the overall amount of waste, they cannot solve the disposal problem alone. And although landfills have complex designs and increasing levels of safety, they are usually unwelcome in most communities around the nation.

Public perception of landfills as threatening to groundwater supplies is the major reason for their unpopularity. New groundwater monitoring rules require more frequent testing at landfills in order to prevent extensive contamination, giving added weight to technical and economic considerations.

The changes have shifted the role of the landfill operator, who must now be knowledgeable about leachate treatment, groundwater contamination and transportation issues. The result, say some observers, is an ever-expanding range of requirements and information and a shortage of well-trained operators.

"Landfill operators may need a higher level of management skill to supervise more waste, equipment and personnel," said Marc Bruner of the Palm Beach County, Fla., Solid Waste Authority.

Business interests have become an increasingly big part of the picture, as corporations purchase and operate more landfills. While private industry can often provide more capital toward running the landfill, it also expects to profit from the site.

The size of landfills ties in with economic concerns, because of a trend toward bigger landfills capable of handling more waste. The requirements for constructing and operating a landfill - one solid waste official estimated the start-up price at $10 million - often force communities to band together to support an MSW facility.

Experts say that the impact of the latest round of regulations may be enough to close smaller MSW facilities and lead the way for larger, regional landfills that also have other waste management equipment and services. This trend would result in fewer landfills and longer distances for waste haulers.

"My idea, at least for municipal solid waste landfills, is that the new regulations are going to force people into larger regional facilities only because of the costs involved," said Ed Repa, director of environmental programs for the National Solid Wastes Management Association (NSWMA). "You can run a 1,000-ton-a-day landfill for one-tenth the cost of a 100-ton-a-day landfill."

The Modern Landfill Recent studies suggest that the single MSW landfill is a dying breed, soon to be a relic as large multitask facilities assume the responsibility of handling the nation's wastes.

Palm Beach County's MSW facility, which includes two landfills, a recycling center and a waste-to-energy plant, is praised by government and private industry as an example of the future in MSW management.

"Palm Beach's facility is a public organization you can compare against a private corporation and they would turn out well," said Greg Rosser, vice president for landfill operations for Chambers Development Co., Smyrna, Ga.

Dr. Debra Reinhart, a professor in the University of Central Florida's Civil and Environmental Engineering Department, Orlando, Fla., envisions the modern landfill as a large facility able to manage waste from separation to reuse to landfilling.

Landfills like the one at Palm Beach, which Reinhart calls an "MSW management park," are beginning to spring up at sites around the country.

But while the future may hinge on huge regional facilities, today's landfills still need to be operated properly and safely until closure. One challenge for landfill operators is promoting waste decomposition, even as design and operation practices are moving away from the moisturization of landfills, which slows the decomposition rate.

The Environmental Protection Agency (EPA) has endorsed the concept of adding liquids to landfills in the past, and Reinhart said that the use of leachate could speed up the decomposition process, which would free space in the facility (see chart on page 22).

Reinhart has written about an emerging landfill type, the reactor landfill, which reduces environmental impact while speeding up the waste decomposition process. But the reaction process, which is likened to a biological system, has different requirements than other forms of waste degradation due to its reliance on a leachate recirculation system. The process maintains moisture within the landfill by using the site's original leachate.

Several academic and industry solid waste management experts have predicted a shift in the role of landfills from storage facilities to bioreactors, citing the cost of closure care as a motivating force behind the change.

"Only a handful of landfills use the bioreactor landfill, but the EPA and the Department of Energy are interested in funding research for it," Reinhart said. "People are beginning to recognize the utility of wet cell technology versus entombment. It's something a lot of people are looking at."

Bioreactor research is being conducted at test cells in several states, including New York, Florida, Del-aware, North Carolina and California, according to Reinhart.

Because leachate recirculation can speed up the stabilization process, it has become the focus of research and experimental efforts. Reinhart predicted that leachate recirculation will become more popular through design and operation experience.

Leachate treatment has traditionally been conducted offsite, but a 1993 study predicted a growing trend toward on-site treatment, including recirculation of wastewater back into landfills. The study, conducted by Future Technology Surveys Inc., Lilburn, Ga., also suggested that leachate treatment costs would rise dramatically in the coming years, while spending on design and consulting services will decrease somewhat. More on-site treatment suggests the need for qualified landfill personnel able to handle the job.

The modern landfill, according to Mark Hammond of the Palm Beach County, Fla., Solid Waste Authority, will incorporate several tasks, requiring a higher level of sophistication from managers and employees.

"I think that landfill managers will be pressured to have integrated solid waste management systems, not just landfills," Hammond said. "Right now, regulations prohibit certain wastes from being landfilled, requiring operators to perform more tasks than they had to do even five years ago."

Groundwater Monitoring Groundwater monitoring, now required at landfill sites to test for contamination, has become one of the most important sections of Subtitle D. Changes in groundwater monitoring and protection techniques and liner systems have raised the level of landfill safety. Increased regulations have shifted the groundwater protection issue from an often poorly understood concept to a crucial aspect of landfill management.

"We've seen, not only from EPA but also through Resource Conservation and Recovery Act (RCRA) requirements in the past decade, an increasing focus on groundwater because it is the primary pathway for contaminants to impact our environment," said Robert Krasko of Groundwater and Environmental Management Services Inc., Lawrenceville, Ga.

But as the scope of landfill operation widens to include sampling and statistical techniques, many operators find themselves overwhelmed by the latest innovations. Experts say that many operators are still struggling with the most recent regulatory requirements. Most people, said Krasko, waited for the regulations to take effect to begin groundwater testing and analysis. The results are often seen in the quality and thoroughness of testing procedures.

"What I see now is that people don't fully understand groundwater quality," Krasko said. "You can't do it with one set of data, you have to look at it historically, four or five times or in multiples. You don't need knee-jerk reactions that don't produce any results."

Krasko, who is working on an EPA groundwater training program, said that operators are slowly becoming more familiar with the proper monitoring techniques and recognizing the importance of groundwater to landfills. "Historically we've not really cared about it," he said. "But the new designs are much more protective of groundwater."

The changes in the federal RCRA program and in state regulations are intended to improve monitoring at landfills using objective scientific tests to determine the location and extent of releases as well as the progress of cleanup efforts.

The minimum monitoring standards set by the EPA are good, Krasko said, but protecting groundwater doesn't end there. Beyond simply testing, operators or their consultants must have an understanding of local hydrogeologic conditions.

"Regulations really drive the system, but regulations don't tell operators that this minimum level may not solve your problems," he said. "Facilities need to be made aware that these are minimum requirements and should read between the lines. When the minimum requirements aren't adequate, it's your responsibility to solve the problems."

But like any scientific procedure, the tests must be performed correctly and understood fully in order to produce usable results. Many tests produce good results only half the time and can be costly.

"Monitoring the groundwater is often an expensive proposition," said NSWMA's Repa. "A lot of states require quarterly monitoring instead of semi-annually, which is a substantial cost."

The new testing requirements also will force some landfills to construct new wells at their sites, depending on their proximity to water sources. While many of NSWMA's members have enough wells, said Repa, some will have to drill more in order to comply with the new regulations. For example, Palm Beach County might have to add about a dozen new well pairs; for others, the number will be much higher.

More drilling and testing means a higher cost to most landfills, and economics play a big part in the impact of Subtitle D regulations. The cost of drilling additional wells for monitoring purposes is a factor that some operators say will be borne out in disposal costs.

Landfills present many challenges, according to Dr. Henry Horsey of Intelligent Decision Technologies, a Boulder, Colo., company that does consulting work for groundwater monitoring programs. "People must understand the statistical and regulatory conditions and come up with an approach that meets the regulatory and statistical assumptions, protects human health in the environment while controlling sampling costs," he said.

Horsey cites the complexities of hydrogeology and statistical procedures as barriers that landfill operators will need to scale. "There are very few people who understand the whole picture," he said. "The test you should use can change from one monitoring period to the next, because every statistical test makes assumptions about the characteristics of the data such as sample size, percentage of non-detects and sample distribution. As you acquire more data, the characteristics can change, so you need to reevaluate which statistical test is most appropriate."

A test may be able to detect a change in the level of groundwater contaminants but might not reveal the source. For that, other procedures might be necessary.

The new monitoring requirements represent a step forward, said Krasko, but also a step into an area of science that can be complex and confusing. "There are still problems in Subtitle C and Superfund. On many tests, about half is useful information, half not. Some of it is not well thought through. This didn't burst upon the scene, but it did burst upon people's awareness," he said.

Operator Training Although landfill operator certification is not nationally mandated, many states and private companies embrace training as a way to create public trust and ensure the competence of their employees. Several states have enacted regulations which cover training and certification as well as yearly updates.

Florida's Department of Environmental Protection (FDEP) has constructed a program of continuing education requirements for all landfill operators. Since 1989, the state's operators have been required to complete at least 15 hours of training in approved courses every three years. The state Solid Waste Management Training Committee approves the courses and operators are required to keep documentation of their training.

"Improvements in landfill design and operational requirements, along with the ever-increasing complexity of waste management, fuel the demand for better-trained operators," said Margaret Chasteen of FDEP's Solid and Hazardous Waste Department. "It is critical that we protect Florida's sensitive groundwater resources."

Florida's training program consists of nearly 20 courses, covering health and safety programs and solid waste management. Landfill operators can take the courses, which are designed and offered by state agencies, the Solid Waste Association of North America (SWANA) or the University of Florida's Center for Training, Research and Education for Environmental Occupations (TREEO), at several locations around the state.

"Landfill operators must have a conceptual understanding of design, monitoring, everything," said Krasko. "They should at least have a fundamental understanding of what groundwater monitoring should be like, and that's not what's been going on for the last 20 to 30 years."

The issue is a simple one: better-trained operators are equipped to manage facilities designed with the latest technologies and practices. But Repa said that many operators consider training important for the public image it presents of "being a good neighbor."

The majority of training programs are unable to produce enough competent landfill operators, said Rosser. "If we're really going to meet the demand and make the public believe we're doing things right, we have to have the best-trained people around. It's like getting your car fixed. Would you take your car to a properly certified mechanic or to someone who isn't? That's what it all boils down to."

However, as the EPA approaches enforcement of Subtitle D regulations, the specter of penalties may provide additional incentive for operator training. The trend toward operators with wider experience is a national one, although the demand for well-trained landfill employees exceeds the supply of adequate training programs.

With relatively few nationally recognized programs, states and private industries have taken on the task of developing training programs for their solid waste personnel. But Rosser emphasized that the nation's colleges and universities could contribute by supplying the market with graduates who have technical and business training.

"There are a lot more issues in running a landfill today, business issues and environmental compliance," he said. "In the past, landfills were run by non-technical people. I think you're going to be seeing more people with technical degrees and skills. I have people like that running landfills right now."

The trend of private ownership of landfills has also carried over to the facilities that haul waste across vast distances. Larger, more remote landfills result in longer hauling routes and an effort to compact waste before hauling. The transportation infrastructure is in place, most say, and is now carrying wastes over long distances.

"Most of the transportation system is already capable of handling the waste," Rosser said. "The means and the methods are already there, the equipment is in place, and it's clean and efficient." Chambers Development presently ships approximately 1,500 tons a day by railroad from New York City to Virginia, and other Northeastern states send refuse to landfills in Ohio and Nebraska.

Rosser predicts the emergence of more transfer stations for waste transportation by railroad and trucking. But since more wastes will be shipped over longer distances, experts believe that private companies are better suited for the development of regional landfills and their affiliated transportation systems.

Future Demands With trends suggesting a shift to regional landfills and an increase in compliance regulation, municipal solid waste management will be impacted in several ways. Subtitle D rules for groundwater monitoring and liner systems make landfill management more sophisticated and place greater demands on the technology and practices operators must know.

"We have something new driving our entire monitoring program," Horsey said. "People don't have a lot of experience and don't understand that the results of statistics have to be put in a hydrogeologic context."

The complexity and range of new practices demand a heightened level of knowledge and awareness on the part of MSW personnel. Accomplishing that goal will raise competency of landfill operators and could result in increased public trust.

"The sophistication of landfill management is going to be greatly elevated," Rosser said. "The level of landfill employees will also increase to where they are recognizing problems in the field and bringing more training and expertise."

Better cooperation between public and private entities is crucial to a smooth waste disposal program, said Rosser, adding that neither will be able to do without the other in the future. But as concern over groundwater protection and public health continues to grow, landfills and the people who oversee their operation will have to adjust to new technical and professional guidelines.

Since the state of Florida began requiring landfill operator certification and training five years ago, the University of Florida's Center for Training, Research and Education for Environmental Occupations (UF/TREEO) in Gainesville, Fla., has been a major source for educating these professionals.

Every year, UF/TREEO's landfill operator short schools draw about 200 people. The center also offers an annual six-part landfill design and management series, which covers the process from planning and permitting to closure and long-term care. The instructors for the series consist of state regulatory officials, professional en-gineers and academic ex-perts in solid waste, hy-drogeology and environ- mental engineering.

With the approval of the Florida Department of Environmental Protection (FDEP), the UF/TREEO center offers 15 courses that can be taken to fulfill continuing education training requirements for landfill operators. In addition, there are nearly a dozen other training classes that have gained state approval. In the past five years, nearly 1,000 operators have completed training courses.

By providing solid waste landfill operator training, the department "intends to elevate the professional status of those in the field of solid waste management to further protect the environment and improve landfill compliance and worker safety," said Margaret Chas-teen of the FDEP.

Florida law stipulates that operators complete 15 hours of training every three years to maintain their status. And UF/TREEO is in the process of developing additional courses.

Originally constructed as a water and wastewater training facility, UF/TREEO has now expanded its scope to offer more than 250 environmental and health and safety training courses last year, including groundwater monitoring, hydrogeology and regulatory compliance. The training seminars are held in Gainesville and at various sites around the state. Faculty members include University of Florida instructors, state and national technical consultants and trainers and regulatory personnel.

Courses range from single-day refreshers to five-day seminars. Some of the courses use computers to model air emissions and stormwater runoff, while others in-clude trips to various wastewater facilities and landfills. Hands-on work is important during the UF/TREEO classes, and the center has demonstration areas for asbestos abatement, backflow and chlorine safety training.

UF/TREEO's health and safety classes cover situations that range from confined space entry procedures to emergency response operations, all with hands-on instruction to illustrate the proper procedures.

For more information on the UF/TREEO Center, call (904) 392-9570, ext. 103.

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