In this subchapter:

(1) Director
The term "Director" means the Director of the United States Geological Survey.

(2) Highly fluorinated compound

(A) In general
The term "highly fluorinated compound" means a perfluoroalkyl substance or a polyfluoroalkyl substance with at least one fully fluorinated carbon atom.

(B) Definitions
In this paragraph:

(i) Fully fluorinated carbon atom
The term "fully fluorinated carbon atom" means a carbon atom on which all the hydrogen substituents have been replaced by fluorine.

(ii) Perfluoroalkyl substance
The term "perfluoroalkyl substance" means a chemical of which all of the carbon atoms are fully fluorinated carbon atoms.

(iii) Polyfluoroalkyl substance
The term "polyfluoroalkyl substance" means a chemical containing at least one fully fluorinated carbon atom and at least one carbon atom that is not a fully fluorinated carbon atom.