### Question
How does the law define federally required commencement date?


### Answer
Under *42 U.S.C. § 9658*, **federally required commencement date** is defined as:

> 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

#### Citation:
  - *42 U.S.C. § 9658*
  - Heading: **CHAPTER 103-COMPREHENSIVE ENVIRONMENTAL RESPONSE, COMPENSATION, AND LIABILITY > SUBCHAPTER III-MISCELLANEOUS PROVISIONS**

