Saint-Gobain Performance Plastics

Investigation and mitigation of PFAS releases from the Saint-Gobain Performance Plastics Facility in Merrimack, New Hampshire.

PFOA was detected in a tap water sample that Saint-Gobain collected inside their facility in 2016. The tap water at Saint-Gobain was from the public water system operated by the Merrimack Village District, which obtains groundwater from a network of water supply wells. This detection of PFOA in the public water system prompted NHDES to immediately initiate an investigation into the source and extent of PFAS contamination. The investigation, conducted by NHDES and Saint-Gobain’s environmental consultants, involved sampling various media, including groundwater, surface water, stormwater, soil and facility emissions.

Early in the investigation it became apparent that airborne transport of PFAS from the Saint-Gobain facility was an important pathway for regional groundwater contamination in several of the surrounding towns. See the Air Emissions Sources webpage for more information.

A major effort to sample water supply wells, both public and private, expanded outward from the facility into the surrounding communities. See our Saint-Gobain Site Investigation history.

Well Sampling and Alternate Water

New state AGQS and Maximum Contaminant Levels (MCLs) for PFAS went into effect in September 2019 that lowered the allowable amount of PFOA in groundwater to 12 ppt (and set individual limits for PFOS, PFHxS and PFNA). Saint-Gobain submitted a "Work Plan for Sampling of Water Supply Wells and Provision of Alternate Water" (and subsequent Addenda) to identify water supply wells within the Outer Boundary of the 2018 Consent Decree that exceed the new AGQS due to releases of PFAS from its Merrimack facility and to provide alternate water to affected residents. Saint-Gobain is actively sampling in this area in accordance with the work plan and has offered to provide alternate water to over 1,800 properties with AGQS violations as of January 2024.

In April and June 2022, NHDES entered into an agreement with Saint-Gobain to provide alternate water solutions to more than 1,100 impacted properties. The agreements outlined the framework for Saint-Gobain to provide safe drinking water, which includes connections to municipal water systems at 529 properties and point of entry filtration systems at 605 properties. Following the April and June 2022 agreements, Saint-Gobain has continued to conduct drinking water sampling and identify properties with AGQS violations. As of January 2024, more than 100 additional properties have been identified that require alternate water solutions by Saint-Gobain.

During the summer of 2022, Saint-Gobain started design work for municipal water connections as well as coordinating the installation of point of entry filtration systems. Contractors for Saint-Gobain began installing point of entry filtration systems in December 2022. As of December 2023, systems had been installed at 540 properties. Saint-Gobain began installation of municipal water lines in the Litchfield area in December of 2023, which will continue through the winter. Additional municipal water lines and connections in the towns of Bedford, Londonderry and Merrimack will begin during Spring 2024 and continue through the summer.

As drinking water sampling identifies properties with exceedances of the state’s AGQS, bottled water will continue to be immediately provided along with proposed alternate water remedies for these properties impacted by the release of PFAS from Saint-Gobain.

Ongoing Site Investigation Activities

Investigation activities at and around the Saint-Gobain facility continue. Current activities include:

  • Groundwater management permit.
  • Additional surface water sampling.
  • Submittal of a remedial action plan.
  • Ongoing monitoring well sampling around the facility.
  • Ongoing residential well sampling.

For ongoing updates, refer to the OneStop website by searching under the NHDES Site #199712055.

How do I request Sampling of my well?

Saint-Gobain is responsible for sampling water supply wells inside the Outer Boundary of the 2018 Consent Decree (CD) to evaluate the extent of groundwater impacts due to releases from its facility. You can determine if you live within the CD by using the PFAS Sampling Dashboard. If you live within the CD and would like to request sampling of your well, contact Saint-Gobain at 1-800-742-8498. If you live outside the CD, you can request sampling of your well by NHDES. 

Fill out the private well testing form  

Determine if you live within the Consent Decree

The Saint-Gobain Consent Decree Outer Boundary can be viewed on NHDES’ PFAS Sampling Map as a shaded area that encompasses parts of Bedford, Hudson, Litchfield, Londonderry, Manchester and Merrimack. The mapper also shows PFAS sampling results that have been submitted to NHDES Environmental Monitoring Database (EMD) and remediation sites that have screened groundwater for PFAS. Remediation sites that have tested groundwater for PFAS are shown on the map as stars that are color-coded based on the amount of PFAS detected. See “Details" button in the upper-left portion of the mapper screen.

PFAS Sampling Map  

Saint-Gobain Site Investigation and other PFAS sites

The OneStop webpage can be used to find documents that pertain to NHDES sites by entering the NHDES site number into the "Any DES Interest ID:” box and pressing "Enter." The NHDES ID number for PFAS waste sites can be obtained from the PFAS Sampling Map by clicking on the star features to open the data-pop up.

OneStop webpage