Demonstration projects were sought for tools, methodologies, or technologies that can reduce the cost of managing the Department of Defense’s (DoD) long-term liability associated with groundwater impacted by chemicals of concern. Such chemicals of concern include per- and polyfluoroalkyl substances (PFAS), chlorinated solvents, energetic compounds, emerging chemicals of interest to the DoD, or mixtures of these chemicals.

The primary focus of this topic area was development of innovative technologies and approaches for managing sites and the associated risks where contamination will persist for a significant period of time after an initial remedy is selected. The following topics were of particular interest:

• Development of cost-effective management tools or technologies to specifically address contaminant source zones in complex geological environments that cause persistent groundwater plumes.
• Development of cost-effective management tools or technologies to address groundwater impacted by emerging chemicals of concern. Such technologies also must address common co-contaminants with these emerging chemicals of concern.
• Assessment of how to better combine existing or new technologies to address complex sites and make informed decisions on transitions from active remediation to passive technologies.
• Optimization, assessment, and/or long-term monitoring tools related to remediation of impacted groundwater.
• Development and evaluation of tools to collect more site data of better quality at lower cost. Site data on groundwater quality, including contaminants and biogeochemical conditions is of particular interest.

In July 2018, the SERDP and ESTCP co-sponsored a Workshop on Research and Development Needs for Chlorinated Solvents in Groundwater. This workshop identified several critical priority demonstration needs for chlorinated solvents in groundwater. A more detailed description of these issues can be found in the report from the workshop. Proposers were strongly encouraged to review the workshop report for additional detail and should have aligned their proposed effort with the identified demonstration and technology transfer needs. For those projects that proposed to address PFAS issues, review of the SERDP and ESTCP memo for specific quality assurance/quality control requirements for all projects addressing PFAS was recommended. 

The following projects were funded. Project overviews will appear below as they are posted to the website.

• Bioremediation of 1,4-Dioxane Using Cometabolic Bioreactors
  • Principal Investigator: Caitlin Bell,  Arcadis, U.S., Inc.
• Phytoremediation for Shallow Sources of PFAS Impacting Groundwater
  • Principal Investigator: Paul Koster van Groos, Aptim Federal Services, LLC
• Management and Mitigation of PFAS Leaching from Concrete
  • Principal Investigator: Jeffrey McDonough Arcadis, U.S., Inc.
• Rapid and Inexpensive Delivery of Particulate Carbon for In Situ PFAS Treatment in Groundwater
  • Principal Investigator: Stephen Richardson GSI Environmental Inc.
• Using Real-time Remote Sensors to Reduce the Cost of Long-Term Monitoring and Remediation Performance Monitoring at PFAS Vadose Source Zones
  • Principal Investigator: Kenneth Walker, GSI Environmental Inc.
• Building the Next Generation Long-term Monitoring Optimization Toolbox: Revitalizing the Maros Platform on the Web
  • Principal Investigator: Lila Beckley, GSI Environmental Inc.
• Development and Application of Injectable Fuels/Adjuncts for In Situ Treatment of PFAS and Co-contaminants in Source Areas by Smoldering Combustion
  • Principal Investigator: David Major, Geosyntec Consultants
• Demonstration-scale Evaluation of a Novel Surface-Modified Clay Adsorbent: Comparison of Fluoro-Sorb, GAC, and IX Resin for the Removal of PFAS and Co-Contaminants in Groundwater
  • Principal Investigator: Christopher Bellona, Colorado School of Mines
• Cometabolic Treatment of 1,4-Dioxane and cVOCs in Groundwater Using an Isobutane-Fed Fluidized Bed Bioreactor
  • Principal Investigator: Todd Webster, Envirogen Technologies, Inc.

The DoD’s Installation Restoration Program (IRP) has set goals to achieve Response Complete (RC) at 95% of IRP sites at active installations, and IRP sites at Formerly Used Defense Sites (FUDS) by the end of FY 2021. Of these sites, groundwater impacted by chemicals of concern is often the most intractable problem. Substantial progress has been made in the past 20 years in the development of technologies for remediation of contaminated groundwater; however, challenges remain. Remedial costs are particularly high at sites where (1) contamination is extensive, but concentrations are low, (2) dense nonaqueous phase liquid (DNAPL) is present in the subsurface, (3) site hydrogeology is complex (e.g., fractured bedrock), or (4) site conditions require extensive long-term monitoring. The National Research Council study, “Alternatives for Managing the Nation’s Complex Contaminated Groundwater Sites” reviews and highlights the technical challenges the DoD faces in managing these sites. 

Also of concern are issues associated with emerging chemicals of concern in groundwater. Chemicals such as PFAS or 1,4-dioxane often co-occur with other chemicals, yet treatment options that are effective for one class of compounds may not be for others. More cost-effective treatment technologies are needed for these emerging chemicals of concern. In situ or ex situ treatment options are of interest, but proposers must be clear on the need for and advantages of ex situ treatment. 

Technologies and methods are sought that have well-defined demonstration/validation questions to address. Proposed technologies should have completed all required laboratory work, although site-specific treatability work prior to the field demonstration is acceptable. Demonstrations should address technical and/or regulatory issues that inhibit the widespread use of the proposed approach across the DoD. ESTCP supports demonstrations at a scale sufficient to determine the operational performance of the remediation technology and to estimate its expected full-scale costs. Full-scale cleanup of specific sites is not performed under ESTCP. Specific DoD demonstration site(s) may be suggested in the pre-proposal, but are not required. 

ESTCP has supported the demonstration of a number of technologies designed for protection and remediation of groundwater. Proposers should be familiar with the ESTCP portfolio of technologies and tools in order to avoid duplication of previous efforts. ESTCP groundwater project descriptions are available on the ESTCP website.