Drinking Water MCLs for PFAS Chemicals — Tennessee

Tennessee follows the federal Maximum Contaminant Levels (MCLs). 

• PFOA: 4 parts per trillion (ppt) 
• PFOS: 4 ppt 

The Sound Science in Regulations Act requires the use of the “best science available” when developing standards for Maximum Contaminant Levels (MCLs) in PFAS and other chemicals for state agency rules that are:

• Adopted after July 1, 2025; and
• More stringent than any applicable federal regulation or adopted in the absence of a federal regulation. Tennessee has no state-specific PFAS drinking water requirements. In TDEC’s Strategy to Assess the Impact of Per- and Polyfluoroalkyl Compounds on Public Drinking Water Sources in Tennessee, the department states that Tennessee will have to adopt any final EPA MCLs for PFAS.

The Tennessee Department of Environment and Conservation (TDEC) has implemented a sampling strategy to monitor PFAS in drinking water, which mirrors the U.S. EPA’s testing requirements.