PFAS investigation, supply well evaluation, and groundwater plume delineation for a former municipal fire station impacted by historic AFFF use.

Nobis Group is providing environmental investigation and regulatory support services to the Town of Bedford for PFAS contamination associated with historical use of AFFF at the former Bedford Fire Station. NHDES requested a focused site investigation after PFAS compounds exceeding New Hampshire AGQS were identified in nearby residential drinking water wells and the property was evaluated as a potential contaminant source. Historical information documented AFFF handling, fire training, equipment cleaning, and decontamination activities at the former station.

Nobis completed iterative site investigations to evaluate PFAS sources, distribution, and migration. Work included records review; sensitive receptor and private water supply well evaluations; soil borings and sampling; monitoring well installation; groundwater elevation surveys; low-flow groundwater sampling; hydrogeologic evaluation; data validation and interpretation; and development of a conceptual site model. The investigation evaluated on-site and off-site conditions, groundwater flow, potential source and recharge areas, and migration toward neighboring properties.

Nobis coordinated with the town, property owners, drilling and laboratory subcontractors, and NHDES. The phased work supported preparation of technical reports and an application for a Groundwater Management Permit. Following permit issuance in May 2026, Nobis continued regulatory coordination, abutter notification, groundwater monitoring, and reporting to support long-term management of PFAS impacts.

challenges

  • PFAS impacts occurred in a developed municipal setting with potential on-site and off-site source and recharge areas, requiring phased investigation across multiple properties.
  • Nearby private water supply wells required sensitive receptor evaluation, property-owner coordination, and clear communication of sampling results.
  • The investigation required differentiation of PFAS patterns associated with historical AFFF use from broader regional PFAS conditions as the site is in the immediate vicinity of the Saint-Gobain Consent Decree Boundary.

solutions

  • Implemented successive soil, groundwater, and drinking water investigations to evaluate source areas, groundwater flow, contaminant distribution, and potential receptor pathways.
  • Established and sampled a monitoring well network and integrated analytical and hydrogeologic data into a conceptual site model for regulatory decision-making.
  • Prepared supplemental investigation reports and a Groundwater Management Permit application, then transitioned the project to permit-required monitoring and reporting.

results

The phased investigations characterized PFAS conditions in soil and groundwater, identified relationships between historical AFFF use and portions of the observed PFAS distribution, and advanced delineation of impacts downgradient of the former fire station. Nobis developed the technical basis for regulatory management of the site and prepared the Groundwater Management Permit application. NHDES issued the permit in May 2026, establishing a five-year framework for groundwater monitoring, reporting, and management of PFAS impacts.