A Novel Clean Up for a Hazardous Landfill

The United States Environmental Protection Agency (USEPA) classifies the nation's most hazardous, uncontrolled instances of chemical contamination as Superfund sites. Overseen by teams of USEPA, United States Department of Justice (USDOJ), and State regulatory officials, Superfund projects are significantly more complex to manage from a regulatory perspective, because a condition that can be exacerbated by the numbers of prior owners of the property and generators of waste released that collectively hold retroactive liability for any contamination found at the Superfund site.

  

In the City of Dover, New Hampshire, a municipal landfill was classified with Superfund status. Past property owners and waste generators, including the City itself and 39 local businesses, all considered Potentially Responsible Parties (PRPs), formed a steering committee to take on the legal responsibility for remediation.

After a full remedial investigation was conducted on the 55-acre area by the New Hampshire Department of Environmental Services (NHDES), a traditional remediation remedy for municipal landfill Superfund sites was selected. The remedy included a multi-layer, hazardous waste‑type cap and on-site contaminated groundwater and leachate treatment system, and was estimated to cost the PRPs $32 million. The City, holding a major portion of the remedial liability, was faced with covering over 40 percent of the cost burden. Then, shortly after remedial pre-design activities, costs incurred by the contractor hired to lead the clean-up effort began to mount beyond the initial scope, and the PRPs decided they needed to seek expert assistance in managing the project.

Digging deeper for more-flexible answers
The PRPs hired GeoInsight to oversee the remediation project from an independent perspective, provide the PRPs with the technical acumen needed to make sound management decisions, and look for ways of adding more flexibility - in the form of better technical solutions and reduced costs - to the overall project. To provide the basis for evaluating possible innovative alternatives to the USEPA Record of Decision, GeoInsight completed an independent review of prior remedial and pre-design investigations. Using this information, GeoInsight surveyed the scientific literature for innovative technologies that could be applied to the contamination and conditions at the Landfill site. GeoInsight's research identified in situ bioremediation as a viable alternative remedy, and a qualified subcontractor was engaged to complete preliminary bench scale testing that confirmed the concept.

Innovating for savings
In situ bioremediation, successfully used at numerous other contaminated and Superfund sites, was an innovative remedy for a municipal landfill Superfund site, particularly because the focus was to treat the contamination rather than simply entomb it under a heavily engineered cap. GeoInsight used its research, re-analysis of site data and conditions, and the results of the bench scale testing to convince the USEPA and NHDES to suspend implementation of the ROD remedy while a pilot test was completed at the Landfill site. The results of the bioremediation pilot study allowed GeoInsight to negotiate a leading-edge treatment‑based alternative remedy without the requirement for a landfill cap. This new approach saved the PRPs over $13 million off the total remediation cost.

In continuing to look out for the PRPs' best interests, GeoInsight determined that it might be possible to reopen the landfill and use revenue generated from reuse of the Landfill to offset remedial costs. Although this landfill reuse plan could have covered virtually all the remedial costs, the City elected not to authorize the plan as a public policy matter. While the remediation project is ongoing, GeoInsight continues to look for new ways to use innovative applications of advanced technologies for the benefit of the PRPs and the City, both financially and environmentally.

A smooth path
"I have extreme confidence in the abilities of the team at GeoInsight. They know how to plan a clean technical, smooth regulatory, and savvy economic path for municipalities like ours. It's a pleasure to work with them."

- Dean Peschel, Environmental Programs Manager, Dover, NH