federally required commencement date
(4) Federally required commencement date (A) In general Except as provided in subparagraph (B), the term “federally required commencement date” means the date the plaintiff knew (or reasonably should have known) that the personal injury or property damages referred to in subsection (a)(1) were caused or contributed to by the hazardous substance or pollutant or contaminant concerned. (B) Special rules In the case of a minor or incompetent plaintiff, the term “federally required commencement date” means the later of the date referred to in subparagraph (A) or the following: (i) In the case of a minor, the date on which the minor reaches the age of majority, as determined by State law, or has a legal representative appointed. (ii) In the case of an incompetent individual, the date on which such individual becomes competent or has had a legal representative appointed.