Evaluating scalable, cost-effective solutions for PFAS reduction across complex solid waste and ash landfill wastewater streams
Challenge
The Hartford Landfill PFAS Pilot Testing Project is focused on a 120-acre closed municipal solid waste and lined ash disposal site in Hartford, Connecticut, which was closed (capped) in 2013 and has been managed by Connecticut Department of Energy and Environmental Protection’s (CTDEEP) Landfill Stewardship Operations Unit since 2014.
The site generates three PFAS-impacted liquid wastewater streams – groundwater flow control system (GFCS) groundwater/leachate, ash cell leachate and landfill gas collection system condensate. Detailed analytical testing confirmed the presence of PFAS in the three wastewater streams, creating the need for treatment solutions capable of addressing current and anticipated discharge and disposal limits/thresholds.
The Hartford Landfill PFAS Pilot Test Project is funded with Connecticut Clean Water State Revolving fund (CW-SRF) Emerging Contaminant Grant funding received from the U.S. Environmental Protection Agency (EPA) through the Infrastructure Investment and Jobs Act (IIJA). Funding is provided by the EPA and administered by CTDEEP to address the challenge of treating variable wastewater streams while identifying efficient, scalable solutions.
Related Services
Solution
CTDEEP and New England Interstate Water Pollution Control Commission (NEIWPCC) engaged TRC to lead engineering design, pilot system construction, operation, monitoring, and testing of a multi-phased program to evaluate PFAS treatment options. The program includes advanced waste stream characterization (chemical, radiochemical, mineralogical and microbial), on-site and off-site pilot system operations and lifecycle cost evaluation, including process waste management.
Technologies evaluated included:
- Pre-treatment approaches: Sequestration and precipitation-based systems
- Conventional media-based systems: Granular activated carbon (GAC) and ion exchange (IX) resin
- Alternative media: Including plant-based polymer adsorbent beads
- Foam fractionation: Bench and pilot-scale testing with reduced waste volume benefits
- Destruction technology: Supercritical Water Oxidation (SCWO) and Electrochemical Oxidation (EOx)
Testing is being conducted across all wastewater streams, including on-site pilot systems (GAC/IX) and initial off-site testing (foam fractionation), with blended wastewater stream flow scenarios evaluated to support full-scale treatment system design.
Results
The program systematically evaluates and identifies effective and cost-efficient PFAS treatment solutions based on performance, feasibility and lifecycle considerations. Led by a multidisciplinary team of technical specialists, the effort will generate actionable, data-driven recommendations to support full-scale system design and implementation. Given the comprehensive nature of the project, and the unique roles of NEIWPCC and CTDEEP in developing public guidance and regulatory programs, the project has a twofold benefit of 1) establishing a scalable, adaptable framework for PFAS treatment at landfill and industrial sites across Connecticut and beyond and 2) assisting regulatory agencies across New England in development of realistic and achievable PFAS treatment criteria.