New Interim NJDEP Soil Remediation Standards for GenX Chemicals

Earlier this month, the New Jersey Department of Environmental Protection (DEP) published interim soil remediation standards for hexafluoropropylene oxide dimer acid and its ammonium salt, which are more commonly known as GenX chemicals and part of the larger family of per- and polyfluoroalkyl substances (PFAS). The following interim soil remediation standards are effective as of June 5, 2023:

Contaminant	CAS No.	Interim Soil Remediation Standard Migration to Ground Water (mg/kg)	Interim Soil Leachate Remediation Standard Migration to Ground Water (µg/L)
Hexafluoropropylene oxide dimer acid & its ammonium salt (GenX)	13252-13-6 & 62037-80-3	Area of Concern/Site-specific	0.40

The interim soil remediation standard for migration to groundwater, which will be determined on an Area of Concern or site-specific basis, is calculated using synthetic precipitation leaching procedure (SPLP) and NJDEP's SPLP Calculator. These new interim standards may have significant consequences for parties conducting remediation or environmental due diligence in New Jersey. We encourage all potentially affected parties to contact the Day Pitney environmental team and/or their respective environmental professionals to discuss potential implications. A complete copy of NJDEP's public notice, which was published in the New Jersey Register on June 5 (55 N.J.R. 1226(a)), can be accessed here.