Veolia Water Delaware is suing a group of companies it alleges contaminated the Red Clay and White Clay creeks with PFAS, seeking to recover at least $34.6 million spent installing treatment infrastructure at its Stanton Water Treatment Plant.
The utility says the contamination has forced it to make costly upgrades to protect drinking water supplied to approximately 40,000 customers, representing about 100,000 people across New Castle County. The Stanton plant draws its source water from the Red Clay and White Clay creeks.
Veolia’s complaint, filed in Delaware Superior Court on August 11, names Ametek Inc., Syensqo Specialty Polymers USA LLC (formerly Solvay Specialty Polymers USA LLC), Solvay Solexis Inc., Niche Polymer LLC, Marshallton Realty Holdings LLC, Westchester Plastics LLC, Coherent Corp., FMC Corp. and Edlon Inc. as defendants.
The lawsuit alleges the companies manufactured, used or disposed of per- and polyfluoroalkyl substances (PFAS) that eventually contaminated waterways supplying the Stanton plant. The allegations have not been proven in court.
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Veolia says testing of raw water has detected PFOA and PFOS at levels exceeding applicable federal and Delaware maximum contaminant levels. The utility has also detected the chemicals at varying concentrations in other samples.
To address the contamination, Veolia selected granular activated carbon (GAC) treatment after considering GAC, closed-circuit reverse osmosis and ion exchange technologies. The utility says the GAC system at Stanton cost at least $34.6 million to build and is expected to cost more than $3.5 million annually for media replacement, disposal and regeneration.
Veolia is seeking to recover those capital costs as well as continuing operating, maintenance, monitoring and other PFAS-related expenses from the defendants. The utility has indicated that any proceeds awarded through the litigation would be used to help provide rate relief to customers.
Veolia began designing the Stanton PFAS treatment system in early 2022, ahead of the new EPA regulations for some PFAS levels in drinking water. It took three years to design and build the 17,600-square-foot facility, which features 42 large vessels, each 22 feet high and filled with 40,000 pounds of GAC.
The lawsuit comes as Veolia has a proposed 42% rate increase pending before the Delaware Public Service Commission, in a proceeding dating back to 2025. Costs associated with removing PFAS from drinking water have been cited by the utility as one factor behind its rising expenses.
Industrial sites targeted in the lawsuit
Several of the sites identified in the complaint are upstream of Veolia’s drinking water plant intakes, the lawsuit states.
Syensqo, formerly Solvay Specialty Polymers, operated a manufacturing facility along Red Clay Creek from approximately 1998 until 2020, where polytetrafluoroethylene (PTFE) was processed. According to the complaint, a Delaware Department of Natural Resources and Environmental Control (DNREC) investigation detected PFAS in soil, sediment, groundwater and surface water at and around the site.
In 2020, DNREC identified Solvay as a potentially responsible party for a PFOA release at the facility. A subsequent settlement required environmental investigation and remedies for contamination. The lawsuit says an October 2025 DNREC letter reported groundwater containing 33,000 parts per trillion of PFOA — described by the agency as the highest PFOA detection recorded in Delaware — and identified deficiencies in the site’s ongoing investigation.
The complaint also targets a former Ametek manufacturing property at 900 Greenbank Road beside Red Clay Creek. PFAS have been detected in soil, groundwater and surface water at the site, according to the filing.
In April 2026, DNREC issued an order directing Ametek, Marshallton Realty Holdings and Niche Polymer to begin remedial work at the property. The required work includes a remedial investigation, human health and ecological risk assessment, evaluation of cleanup alternatives and implementation of a final remedial action plan.
Other defendants are associated with sites near White Clay Creek or its tributaries. Veolia alleges operations involving fluoropolymers, ceramics, polymeric materials, pesticides and other manufacturing processes created pathways through which PFAS could reach White Clay Creek and ultimately the Stanton Water Treatment Plant.
Delaware adopts federal PFAS limits
The lawsuit also points to increasingly stringent drinking water requirements as a driver of Veolia’s treatment costs.
U.S. EPA regulations finalized in 2024 established maximum contaminant levels of four parts per trillion for PFOA and PFOS, and 10 ppt for PFHxS, PFNA and GenX chemicals, along with a hazard-index requirement for certain PFAS mixtures. Delaware adopted the federal limits effective January 15, 2026.
Veolia alleges the defendants are jointly and severally liable for contamination and its resulting costs. Its claims include public and private nuisance, negligence, trespass, recovery of remedial costs under Delaware’s Hazardous Substance Cleanup Act, strict liability for abnormally dangerous activities and negligence per se.
The utility says the lawsuit does not seek damages related to PFAS associated with aqueous film-forming foam, or AFFF, commonly used to suppress flammable-liquid fires.
