Expert Q&A: Jennifer Deal Discusses Solid Waste Development and Planning in the Southeastern United States
Jennifer Deal has more than 20 years of experience as an environmental engineer. She has extensive knowledge in the design, permitting, and construction of solid waste management facilities, groundwater monitoring, and regulatory compliance. Jennifer has helped lead permitting, due diligence, site and contamination assessments, and remediation projects for clients throughout the Southeastern United States. Jennifer also is a skilled project manager, assisting her colleagues in coordinating multidisciplinary projects, financial management, report preparation, proposal writing, and more.
Jennifer has been a mentor to young engineers entering science, technology, engineering, and mathematics (STEM) fields as part of Tetra Tech’s Fearless Entrepreneur Program. She is passionate about sharing the environmental engineering field with children and visits classrooms to explain how landfills work. During the COVID-19 pandemic, she spent time working with young professionals to help identify creative strategies for working virtually with clients, supporting our next generation of industry experts.
Jennifer received a Bachelor of Science in Environmental Engineering from the University of Central Florida in 1997. As a student at, she took the new landfill design course in the environmental engineering curriculum. Her advisor asked her to try the course because he thought she would enjoy it and do well, and he was right. Jennifer took the course and came to appreciate the planning and design aspects associated with permitting a landfill site. She turned this into her career and is now is a registered Professional Engineer in Florida and several other states in the Southeast.
What are some of the newest developments in landfill development and planning?
There have been many new developments over the past few years. Beneficial use of landfill gas such as BioCNG, a system for converting biogas into a renewable natural gas, is a recent development that offers a suitable alternative for vehicle fuel. The types of waste that landfills have to deal with is changing and we help clients adapt to this evolution of waste streams. For example, there has been an increase in disposal of coal combustion residuals (CCR) in municipal solid waste landfills. This is significant for landfills, since constituents leaching from coal combustion residuals can be detrimental to proper function of the leachate collection systems. Another example is a reduction in disposal of organic waste, which can affect production of landfill gas. Additionally, the use of alternative final covers is on the rise, including exposed geomembrane covers and closure turf type products. These alternative final covers allow the owner to defer some closure costs while reducing leachate generation and saving on operating costs.
What are the key factors you consider when working on landfill projects in the Southeast?
One consideration for landfills constructed in the Southeast is severe weather, including hurricanes. Wind and rain on uncovered slopes increases litter and leachate generation. High winds also can damage uncovered geosynthetics on exterior slopes or in new cell liner systems. Sites must have a plan for preparation and operation for these weather conditions. We typically include basic emergency planning for our landfill clients during permitting.
Another consideration is geology, which varies in the Southeast—one area may have clay underlying the surficial soils while others have sand. Site-specific studies are required to determine whether natural soils or geosynthetics will be required in the bottom liner system. Sinkholes also are a possibility in some areas. Extensive subsurface investigation may be required to determine if there is a risk of a sinkhole at the site.
What are some of the major challenges and complexities facing landfill projects today?
Landfills will always face challenges. One common issue I see is public opposition. Landfills often are subject to rejection from local communities not wanting them near their homes. However, they are most often the least expensive option for communities, compared to such options as waste-to-energy. Tetra Tech assists our clients with public outreach that can help communities understand how the landfills operate and build relationships between the landfill and the community. It also can be difficult to ensure adequate funding for closure, long-term care, and potential for extended care periods, referred to as custodial care. Many landfills are required to cover long-term care for 30 years, and the cost of this is a challenge for many clients.
Additionally, ensuring the site has available sources of soil for both operations and closure is a common challenge. Many landfills use alternative daily cover to save on soil usage and costs, and Tetra Tech has helped many of our clients obtain approval to use alternative daily cover at their sites. The benefit is two-fold—our clients can save money on purchase of soil and we help conserve natural resources.
What are some of the coming challenges our clients may face in your region and how can they begin to prepare?
We expect regulation of emerging contaminants, PFAS in particular, to be one of the biggest obstacles for our clients in the coming years. To prepare for the associated challenges, sites need to begin assessing incoming waste streams for their potential to contain these contaminants, prepare for potential pretreatment of leachate prior to off-site treatment and disposal, and begin background assessment of these contaminants in groundwater. Tetra Tech assists clients with waste stream evaluations and auditing of new disposal customers for potential contaminants that may negatively affect their operation.
Facilities also should consider planning now for management of organic waste. We see diversion of organic waste for recycling/processing becoming more common in the near future. As a leader in organics management planning, Tetra Tech assists in the transition towards effective organics resource management for the generation of renewable products. We help clients integrate organics management techniques into existing infrastructure and/or plan and develop new, efficient facilities.