Frank Sweet, chief executive of the environment & energy global business line at AECOM, shares his views on the progress made in the field of environment remediation, and the challenges that still need to be overcome.

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In its relatively brief history, the field of environmental remediation has delivered remarkable progress.

Spurred by landmark legislation like the EPA’s Superfund Act and similar legislation across the globe, the past several decades have seen 1200 major sites in the United States with groundwater contamination under control, more than 1500 sites with human health and environmental risk reduced , and tens of thousands of state lead sites in similar position — a tremendous achievement. 

And yet, despite such considerable progress, remediation challenges have only accelerated.

Emerging contaminants like PFAS pose new health and environmental threats, many of which are only just beginning to be fully understood. Regulators have responded by implementing far more stringent rules to limit exposure to such contaminants.

Meanwhile in the U.S. record federal funding has accelerated remediation — and launched a bit of a renaissance in the industry. As a result, the global environmental remediation market is expected to roughly double between 2022 and 2032.

This is not just accelerating the rate at which we work, but also how and, moreover, why. 

Remediation has always been motivated by more than just environmental considerations.  Programmatic goals include protecting human health and the environment, involving communities in the process, and returning impacted sites to productive use. But as the inequities of contamination come into even greater focus, our work has taken on a social mission.

It is now well established that economically disadvantaged communities remain far more likely to be exposed to pollution, with a disproportionate share of low-income populations in the United States residing near EPA-designated Superfund sites. 

As a result, it’s imperative that remediation mitigate environmental harm while also providing social value to help counter negative impacts on communities. Climate change and the biodiversity crisis have likewise adjusted the scope of work: more than ever, we’re working with clients to cut emissions and provide nature-based and nature-positive solutions.

These changes in our field have necessitated a new approach — regenerative remediation.

The aim of regenerative remediation is to maximize benefits of mitigation across environmental, social, and economic systems. It can take many forms, but its central objective is to exceed the typical objectives of remediation — eliminating pollution while providing solutions to an array of additional challenges.

The Kaohsiung Oil Refinery (KOR) is an excellent example of regenerative remediation at scale.

Built in Kaohsiung City, Taiwan in 1965, the KOR once powered what was coined the country’s ‘economic miracle’. But by 2015, the refinery was largely shut down, and vast vacant, contaminated land remained. 

Our teams were tasked with the site’s remediation. While the extent of the work was massive — treating more than 417,000 cubic meters of contaminated soil — what set it apart was a uniquely sustainable delivery method.

Rather than relying solely on traditional energy and carbon-intensive methods such as off-site landfill disposal or thermal desorption, we have employed bioremediation — a nature-based solution —to remedy the site. Petroleum impacted soil was excavated, adjuncts and water were added, and the soils were placed in biopiles. Today, the final phase of remediation is underway, bringing the site one step closer to becoming a potential home for the science parks critical to Taiwan’s high-tech economy.

However, regenerative remediation can offer more than just emissions reductions. It can also deliver social and natural infrastructure. 

That’s certainly the case with the Dale Hodges Park project, which transformed a gravel pit with contaminated soils into both a public park and a stormwater management facility. 

The marriage of parkland and stormwater treatment relies on a multi-stage, natural treatment process we helped deliver with our project partners. By successively removing significant amounts of sediment, initial treatment ponds allow abundant green infrastructure to further polish the water before discharging it to the river.

The site’s many features — ponds, wetlands, streams, and culverts — formed the basis of the park, and were designed with pedestrian access and biodiversity uplift in mind. Together, they give visitors an inside look at the treatment process and this new model of remediation.

The KOR and Dale Hodges Park projects stand as just a few examples of our industry’s generational shift towards regenerative remediation. Both respond to an increasing awareness that if contamination leaves lasting harm to communities, then remediation must serve as a springboard for positive social and environmental outcomes.

We as practitioners couldn’t be more excited for this moment to reimagine remediation. We get to think more creatively — and deliver even greater benefits through our work. It’s an immensely gratifying approach.