Green remediation, or, to quote the Environmental Protection Agency (EPA), “the practice of considering all environmental effects of remedy implementation and incorporating options to maximize net environmental benefit of cleanup actions,” has long been embedded within the context of cleanups under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). However, recent years have seen a heightened focus on and implementation of green policy. This shift likely stems from growing concerns around climate change and the urgent need to safeguard critical resources like water.
Discussion surrounding green remediation began to pick up around 2009. It was then that the EPA requested the ASTM to prepare a green remediation standard. EPA, Green Cleanup Standard Initiative Update, Sept. 2009. Initiated in 2009, the task force’s work concluded by publishing the Standard in November 2013, which was subsequently updated in 2016. See Standard Guide for Greener Cleanups, ASTM E2893-16e1 (Standard). The Standard acts as a guide to complement regulatory and voluntary cleanup programs throughout each phase of the cleanup. The Standard revolves around the EPA’s five core elements: Energy, Air Emissions, Water Resources, Material and Waste, and Land and Ecosystem.
Separate from the Standard, the EPA issued a widely referenced policy memorandum titled Consideration of Greener Cleanup Activities in the Superfund Cleanup Process (Memorandum) on August 2, 2016. There have been related policy directives before and after this Memorandum, but it still stands as a leading policy statement. The Memorandum recommends two approaches: a Best Practices (BP) approach for sites with less complex issues and a Footprint Analysis for more complex sites. But the choice to conduct either analysis remains within the agency’s discretion. It’s clear (and reiterated several times in the Memorandum) that greener cleanups should not be considered substitutes for other threshold requirements or specific cleanup objectives.
Green remediation comes in various shades of complexity. To illustrate a linear progression from simple to complex examples, we might consider remedial options such as using shorter access and haul roads to reduce emissions. Further along the spectrum, we might see responsible parties utilizing onsite resources to generate electricity instead of offsite sourcing or equipping heavy machinery with diesel-electric power trains and implementing zero-idle policies. More complex examples include using biodegradable material for items like sandbags, technology-driven sediment control through piping and sediment blankets, renewable energy applications, limiting of operations to daylight hours, and grey water reuse.
Further, more complex green techniques can limit the scope of remedial impact to protect native species of plants and animals, reduce impact on wetlands by modifying or downsizing system components, and limit the remedial footprint while still being protective of health and environment. The concept of designing and constructing remedies with considerations for beneficial reuse and biodiversity preservation represents an integrated approach to environmental remediation. It’s about not just cleaning up the site to mitigate environmental damage, but also about considering how the site can be reused in a way that contributes to the local ecosystem and community.
The process begins by understanding the ecological context of the site. This involves studying the local ecosystem—along with its components and needs—and considering how the site can be developed to support these needs. Preserving biodiversity becomes a core design objective, guiding decisions about how the site is remediated and eventually reused.
If the site is located near a body of water, the design and construction of the remedial solutions could incorporate features that support local aquatic life, such as constructing wetlands or including features that prevent harmful runoff into the water. For example, at the Aerojet-General Corporation Superfund Site, excavation of contaminated soil was limited to preserve natural wetlands. This and other examples can be found on the EPA’s Green Remediation Focus website’s Profiles of Green Remediation page.
In terms of beneficial reuse, the site could be designed to serve a useful purpose post-remediation. This may be as simple as creating a green space for the local community or as complex as developing infrastructure to generate renewable energy. The goal is to create a site that not only mitigates the previous environmental damage but also provides ongoing environmental and community benefits.
Moreover, these considerations can lead to innovative solutions that combine remediation with long-term ecological and social objectives. For instance, a remediated site could be transformed into a community garden, supporting local food security while offering educational opportunities about sustainable practices. Or it could be redeveloped to support local wildlife, becoming a sanctuary or reserve that enhances local biodiversity.
There are resource documents available to assist in these efforts. The EPA has developed a methodology for understanding and reducing a project’s environmental footprint. It is a seven-step process used to quantify the footprint and can help identify the best practices available for addressing footprint contributions that are identified to be of particular concern. See U.S. EPA, Methodology for Understanding and Reducing a Project’s Environmental Footprint (Feb. 2012); see also U.S. EPA, Green Remediation: Incorporating Sustainable Environmental Practices into Remediation of Contaminated Sites (Apr. 2008).
The concept of designing and constructing remedies while considering site reuse is about transforming the way we view and approach remediation. It’s about seeing these projects not just as a way to clean up environmental damage, but as an opportunity to create spaces that benefit both the environment and the community.
But true sustainability and resilience in green techniques require a focus on the entire canvas—on the idea that the remedial plan should prevent “more harm than good.” John Muir famously said: “When we try to pick out anything by itself, we find it hitched to everything else in the Universe.” This idea is at the heart of site remediation, which often involves a delicate balance between reducing a minor public health risk and increasing risks to workers, ecosystems, and strained resources.
Within the five core elements of green remediation (Energy, Air Emissions, Water Resources, Material and Waste, and Land and Ecosystem), remedial actions should be optimized to maintain this concept. Remediation aims to reduce environmental stressors by blocking exposure to receptors. Practices such as soil removal or groundwater pumping can disrupt ecosystems, taking decades to recover. To be genuinely “dark green,” remedial actions must be justified and optimized, recognizing that the end result is always a balance between risks, costs, benefits, and remediation viability. The challenge may lie in determining when to halt remedial work to allow ecosystems to recover from physical disruption.
Finally, it’s important to underline that “green” should not only denote an environmentally friendly approach but should also encapsulate the principle of resource maintenance. When protecting health and the environment, the green remediation approach champions the preservation and sustainable use of resources. It propels us towards a future where environmental cleanup not only mitigates damage but also strives to minimize any further disturbances and depletion. This understanding serves as a powerful reminder that our environment is an interconnected web of systems, where the protection of one element often necessitates the preservation of another. As we continue to refine and expand green remediation practices, our focus should remain on striking a balance between restoration and resource conservation, ultimately aiming for a world that is as safe and healthy for humans as it is sustainable and prosperous for the environment.