Stephens Valley Garbage Disposal Issues

The Valleyist Papers

A COLLECTION OF ESSAYS 

WRITTEN IN FAVOUR OF THE IMPROVEMENT OF STEPHENS VALLEY

Author – Jo House, PE

Edition 3. Issue 01.

Introduction

Christmas in Stephens Valley is a season that is focused on gift giving, family gatherings and worshiping at your local church or synagogue. The last thing on any person’s mind is the collection and disposal of garbage. However, this is the busiest time of year for the generation of household trash. The week after Christmas is literally overwhelming at landfills which leads to this discussion of trash.

It could be argued that garbage disposal, aka solid waste disposal, is one of the least interesting and most disgusting aspects of any civilization. After all, garbage is smelly and nasty and most people don’t want to be anywhere near it whether it is in a container or landfill. However, solid waste management, as it is formally referenced, along with water treatment, and wastewater treatment are the three services necessary for a healthy community. Almost every community in Tennessee prior to 1990 had a dump where citizens could deliver their trash. The management of each dump was different in that some dumps buried the trash in trenches dug down as far as the equipment could dig and others simply spread it out on the surface of the ground and covered it occasionally with soil. Open burning of trash was also a convenient way of managing the volume of disposal.

Development of Solid Waste Zoning and Regulations

There were regulations in Tennessee for the operation and permitting of landfills prior to 1990, but those regulations did not address all the potential impacts to human health and the environment that could result from a poorly operated “dump”. However, the regulations in Tennessee began changing in 1988. The change was initiated in response to a proposal by a group of individuals who proposed to permit a household waste landfill in the southwest corner of Dickson County that adjoined Humphreys and Hickman County. The negative reaction to the proposed landfill resulted in state senator Doug Jackson formulating a bill to basically give municipal and county governments the ability to control siting of landfills in rural communities without zoning laws and ordinances. The legislation developed by Doug Jackson was promulgated on June 2, 1989 and was designated as the Jackson Law. However, for the law to be in effect it had to be adopted with a majority vote of the governing body of a county or city government. Basically, upon adoption of the Jackson law, all cities and counties were provided with the arbitrary and capricious right of refusal of any proposed landfill regardless of the protective quality of the design or location. It also could stop expansions of any landfills permitted after June 2, 1989.

In 1990, the Tennessee Division of Solid Waste Management (TDSWM) adopted a draft set of solid waste regulations developed by the Environmental Protection Agency (EPA) for the design, permitting, and operation of landfills. The final set of solid waste regulations were adopted in 1993 and were referenced as the Subtitle D landfill regulations. These regulations set forth minimum landfill design, operation, and monitoring requirements that would provide an acceptable level of risk relative to human health and the environment. These regulations were specifically designed to protect groundwater resources. Upon promulgation of the Subtitle D landfill regulations, it was believed that the requirements set forth in the regulations provided a level of protection for human health and the environment that the Jackson Law was no longer necessary and could be rescinded. 

Additional local zoning and environmental regulations that landfills must comply with are as follows:

Local Government

Regional Solid Waste Board

County and Municipal Government Zoning

Municipal Government Stormwater Regulations

Municipal Government Air Boards in Memphis, Nashville, Knoxville, Chattanooga

Tennessee Department of Environment and Conservation

Tennessee Division of Solid Waste Management

Tennessee Division of Water Resources

Tennessee Division of Natural Resources

United States Environmental Protection Agency (USEPA)

New Source Performance Standards and Emissions Guidelines

Greenhouse Gas Emissions 

National Pollutant Discharge Elimination System (NPDES) Stormwater Regulations

United States Federal Aviation Administration

United States Army Corp of Engineers

Waste Generation and Disposal in Stephens Valley and all Middle Tennessee

A conservative estimate of the volume of trash generated in middle Tennessee each day approximates 8,700 tons (some estimate the daily trash generation volume closer to 10,000 tons). The reported remaining disposal capacity of all landfills in middle Tennessee approximates 29,477,691 cubic yards. Using all the reported waste generation rates, the currently remaining permitted landfill capacity volumetrics along with the reported in place density of the waste, the remaining life of all landfills in middle Tennessee is 8.3 years. This estimate does not include consideration for the continued population growth in middle Tennessee. So, if all things remain 8,000 to 10,000 tons will have to be shipped long distances every day. (FYI – the railroad is not a viable solution) 

It may be noted that some of the landfills could possibly be expanded. The Middle Point Landfill just north of Murfreesboro is the largest landfill in Middle Tennessee and has provided disposal for one third of the trash generated in middle Tennessee and the majority of Nashville trash generated in Nashville. However, Middle Point has recently lost law suit seeking permission for an expansion. As a result, it is estimated that at the current rate of waste acceptance Middle Point will reach the permitted disposal capacity in 4 years and will have to close. The Bi-County Landfill located just north of Clarksville can be expanded, but that landfill is primarily operated to serve the citizens of Montgomery and Stewart County. It is uncertain if the West Camden Landfill can be expanded at this time. Smith County may be able to expand its landfill at a significant cost due to the presence of sinkholes, wetlands, and streams in the immediate vicinity. The Cedar Ridge Landfill located near Lewisburg in Marshall County is situated at a location with shallow bedrock which makes the design of expansions difficult and provides less soil for construction of liners and covers.

In summary, the potential for permitting a new landfill in middle Tennessee is extremely low due to the adoption of the Jackson Law by most county and municipal governments in Tennessee. As previously discussed, the Jackson Law provides all county and municipal governments the arbitrary and capricious right to refuse any proposal to permit a new landfill or expand an existing landfill permitted after June 2, 1989. Unfortunately, although there have been and are continuing to be attempts to develop and implement other technologies to manage the generation and management of solid waste the landfill remains the most practical and reliable option.

Landfill Containment Design

Landfills must be designed such that there is no release of constituents/pollutants from the waste mass. Specifically, all landfills are tasked with the collection and proper disposal of all liquids/rainwater that enters the landfill. This liquid is referred to as leachate and must be disposed of with an acceptable technology or at a wastewater treatment facility. In addition, landfills must collect and properly dispose of the gas generated from anaerobes that metabolize the organic fraction of the waste. The gas can be converted to electricity and can be scrubbed and used to operate vehicles used at the landfill. In addition, the landfill gas can be piped directly to industrial consumers. 

  

Typical Section of a Landfill Final Cover and Liner/Leachate Collection Barrier System

Alternate Disposal Technologies

There are several alternative solid waste disposal technologies that have been developed to replace landfilling and incineration. These alternatives have been developed to minimize environmental impact, promoting resource recovery, and reducing the overall volume of waste. However, many of these technologies work best in the laboratory and on a small scale. The cost to construct and operate alternate waste management technologies has limited widespread implementation. Those technologies are as follows: 

⦁ Waste-to-Energy (WtE):

⦁ Incineration: Converts solid waste into heat, electricity, or steam. Advanced incineration technologies can be designed to minimize emissions and recover energy.

⦁ Gasification: Converts waste into syngas, which can be used for energy production or as a chemical feedstock. It is considered more environmentally friendly than traditional incineration.

⦁ Anaerobic Digestion:

⦁ Biological Process: Breaks down organic waste in the absence of oxygen, producing biogas (methane and carbon dioxide) and nutrient-rich digestate. Biogas can be used for energy, and digestate can be used as fertilizer.

⦁ Pyrolysis:

⦁ Thermal Decomposition: Heats waste in the absence of oxygen, producing biochar, oil, and gas. Biochar can be used as a soil amendment, and the oil and gas can be used for energy.

⦁ Plasma Gasification:

⦁ High-Temperature Process: Uses a plasma torch to convert waste into syngas with minimal emissions. It can handle various types of waste, including hazardous materials.

⦁ Mechanical Biological Treatment (MBT):

⦁ Combination of Mechanical and Biological Processes: Involves sorting, shredding, and treating waste with biological processes to recover materials and produce a more stable residue for landfilling.

⦁ Hydrothermal Carbonization (HTC):

⦁ Wet Thermal Conversion: Converts organic waste into a carbon-rich material through high-temperature and high-pressure water treatment. The resulting hydrochar can be used as a solid fuel or soil conditioner.

⦁ Landfill Mining:

⦁ Extraction of Resources from Landfills: Involves the excavation of old landfills to recover valuable materials, such as metals, plastics, and soil. It can reduce the environmental impact of landfills and promote resource recovery.

⦁ Recycling and Material Recovery:

⦁ Source Separation: Encourages separation of recyclable materials at the source to improve the efficiency of recycling processes.

⦁ Advanced Sorting Technologies: Utilizes advanced technologies such as robotics and artificial intelligence for more efficient sorting and recycling of materials.

⦁ Waste Reduction and Prevention:

⦁ Zero Waste Initiatives: Focus on reducing waste at the source through sustainable product design, consumption patterns, and lifestyle choices.

Many solid waste facilities are continually evaluating the efficacy of alternate technologies or even a combination of these technologies. 

For example, the Williamson County Solid Waste Department had an issue with the disposal of large quantities of leachate so in 2000 they designed and implemented an aerobic bioreactor. An existing six-acre waste cell with a composite liner system was retrofitted with injection wells and piping such that the leachate could be injected into the waste mass from other areas of the landfill. Piping to convey the movement of air with large blowers into the waste mass was also installed which would keep the conditions for the generation of landfill gas to a minimum since landfill gas is produced under oxygen deficient environments. The bioreactor was operated for more than a decade successfully eliminating thousands of gallons of leachate and stabilizing the potential leaching of contaminants from the waste mass.

Brief Explanation of Recycling Technologies

The following paragraphs touch on the unintended consequences of recycling some of the most recycled materials.

Aluminum Recycling is probably the most economical form of recycling. However, the waste generated from the secondary smelter is comprised of salt, potash, volatile organic compounds, heavy metals, and large volumes of particulate matter/dust. There are two specific heavy metals (aluminum nitride and metallic aluminum) that are exothermic (produce heat) when introduced to water. If the secondary smelter waste is disposed of with household trash in a municipal solid waste landfill exposed to rainfall the aluminum nitride and metallic aluminum compounds begin to react and become hot enough to ignite the organic fraction of the waste. In addition, the reaction of those compounds results in the emission of ammonia gas at extremely high concentrations. Germany does not allow land disposal of this waste as it has developed technologies to remove the salt and potash for reuse. The process also reduces the concentration of heavy metals from the waste material. This technology has been entertained in the United States but has yet to be implemented due to economic restraints.

Cardboard Recycling

For clarification it should be noted that hardwood trees are not used for the manufacture of cardboard. Pine trees are grown as a crop for the manufacture of cardboard. However, cardboard recycling is an economically viable alternative that has environmental benefits. Nevertheless, recycling cardboard results in the generation of wastewater during pulping process, ink and adhesive removal processes that must be treated before discharge. Each time a box is recycled at a facility in Tennessee approximately 12% of that box ends up as wastewater discharge.

Plastics Recycling

Many concerned citizens have diligently been committed to separating plastics to comply with the proper protocols for the collection of plastics for recycling in an effort to minimize the impact of plastic pollution on plant and animal life most notably in the oceans around the world. Unfortunately, these efforts will make no noticeable impact at all due to several challenges which are as follows:

⦁ None of the challenges to plastics recycling is more daunting than the estimated 242 million metric tons of plastic generated in the world every year of which the United States is one of the top generators. 

⦁ Another major challenge is that the composition of plastics varies even in the same container which creates difficulties in the recycling process so that it is harder to isolate the base materials that can be recovered.

⦁ The recycling technologies for plastics also pose issues. Presently, chemical recycling has been touted as the promising new technology. Chemical recycling typically falls into two categories: plastic-to-fuel and plastic-to-chemical both of which use incineration. Plastic-to-fuel conversion involves pyrolysis or gasification, both of which use heat and chemical processes to break down plastic waste into products that are turned into fuels. The plastic-to-chemical process uses treatments such as heat and solvents to create feedstocks that proponents claim can be turned into other chemicals or new plastics. (Forbes July 2022) Each of these processes have impacts to human health and the environment as well as social and economic issues. The plastic-to-fuel technology generates toxic emissions including greenhouse gases when incinerated.

Basically, the challenges described above reduce to one conclusion which is that plastic recycling is just not economical. It's more often less expensive for companies to buy new plastic than it is to buy recycled plastic. Therefore, since it is less expensive for companies to buy new plastic there's not a huge market for recycled plastic. Additionally, China stopped buying U.S. plastic wastes in 2017 which basically destroyed the only viable market for recyclable plastic. 

Many environmentalists contend that the plastics industry has sold the public on the false narrative that plastics are recyclable, when in fact the process is prohibitively expensive, and few U.S. facilities have the capacity to do it. Specifically, California Attorney General Rob Bonta opened an investigation into the role petrochemical companies have had in misleading consumers. Another outspoken critic of the plastic recycling narrative is former EPA Regional Administrator and President of Beyond Plastics Judith Enck who stated that the plastics industry "must stop lying to the public about plastics recycling". "It does not work, it never will work, and no amount of false advertising will change that."

So, like numerous other well intended efforts to recycle waste the plastics collected for recycling also end up in landfills or are incinerated.

Concluding Remarks

While the Hudgins Disposal team does a wonderful job collecting our SV garbage, they transport it to a landfill, and that is becoming a big problem. Landfills are tasked with disposing of highly odorous and hard to manage waste materials whose generator is not accountable in any form or fashion. All complaints regarding the final disposition of odorous and hard to manage wastes are directed to the landfill who had no part in its generation. For years highly reactive wastes from secondary aluminum smelters, undigested sewage sludge from municipalities, and other industrial waste sludges with high concentrations of heavy metals have been delivered to landfills which upon delivery is no longer the responsibility of the generator to manage. Environmental groups and the public impacted by the operations undertaken by landfills never seem to even consider addressing the generator(s) whose waste can create issues once disposed.   

Hopefully, a technology will be developed to replace landfills but until that happens the primary technology for solid waste management is land disposal. However, the question is if a technology can be developed before the state of Tennessee is completely out of landfill disposal capacity since laws have been adopted that, for the most part, prohibit any new permitting of landfills in Tennessee. A day of reckoning is approaching for SV, and all of middle Tennessee. When we throw away our garbage, it isn’t really gone!

Author - Jo House, PE