How a solid waste landfill transformed into a concerning elevated temperature landfill

New research explains how the Bristol Virginia Solid Waste Landfill has undergone a significant transformation into an elevated temperature landfill. Elevated temperature landfills are a specific type of landfill where buried waste undergoes chemical reactions, leading to increased internal temperatures.

A recent study published in the journal Environments by researchers from the University of Kentucky analyzed critical data from the Bristol Virginia Solid Waste Landfill obtained from two government agencies: the United States Environmental Protection Agency (EPA) and the Virginia Department of Environmental Quality (VDEQ).

Understanding elevated temperature landfills is crucial because they differ substantially from traditional landfills. They experience significantly higher internal temperatures, often reaching levels that can accelerate the decomposition of waste materials. These elevated temperatures are typically caused by chemical reactions within the landfill, frequently triggered by the breakdown of organic matter or the presence of specific waste types.

While increased temperatures can expedite waste decomposition, they also raise significant environmental concerns. Elevated temperature landfills can generate higher volumes of methane, a potent greenhouse gas, along with other unpleasant odoriferous gases, and leachate, a contaminated liquid that can pollute groundwater. Among the odoriferous gases, chemicals such as hydrogen sulfide (H₂S), sulfur dioxide (SO₂), and ammonia (NH₃) can be exacerbated at high landfill temperatures.

An important characteristic of the Bristol Virginia Solid Waste Landfill is that it was created over a deep quarry site. Such a design allows high gas pressure to be created in the deeper layers, where heat accumulates through thick layers of waste. Moreover, the quarry site design explains the accumulation at depth not only of gas but also of liquid leachate that cannot be removed.

The study investigated potential causes of the transformation at the Bristol Virginia Solid Waste Landfill and theorized that the transformation into an elevated temperature landfill may be linked to the historical disposal of certain waste materials. The researchers pointed to the past landfilling of coal ash or incinerator ash as potential contributing factors over other wastes such as aluminum dross.

Coal ash is a byproduct of coal combustion that—like incinerator ash—often contains substances that can react with water and oxygen, releasing heat in so-called exothermic reactions that contribute to the elevation of temperatures within the landfill. Once elevated temperatures were reached, the landfill became a more homogeneous reactor where the decay of waste was accelerated.

The potential transformation of the Bristol Virginia Solid Waste Landfill into an elevated temperature landfill carries significant implications for environmental management and public health. Understanding the ongoing processes at the landfill is crucial for developing effective strategies to mitigate potential risks.

The research suggests that further actions are needed. For example, new temperature studies and analyses of landfill gas composition and leachate should monitor the evolution of the elevated temperature landfill. It is imperative that management strategies for the Bristol Virginia Solid Waste Landfill are developed and implemented to appropriately address the environmental impact of this elevated temperature landfill. Measures such as gas capture and utilization systems or advanced leachate collection and treatment technologies are recommended.

By proactively addressing these issues, authorities can ensure the safe and environmentally sound operation of the Bristol Virginia Solid Waste Landfill and protect public health and the environment.