I. INTRODUCTION The Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended, (CERCLA)(1) does not expressly impose liability. Rather, CERCLA provides generally in definitional section that the terms `liable' or `liability' under this subchapter shall be construed to be standard of which obtains under section 1321 of Title 33,(2) which is Section 311 of Clean Water Act.(3) As of time of CERCLA's enactment in 1980, federal courts had construed Section 311 of Clean Water Act to impose strict liability.(4) Therefore, numerous federal courts have concluded that CERCLA also imposes strict liability on four statutory categories of responsible persons for costs and damages resulting from release or threatened release of a hazardous substance from a vessel or facility into environment.(5) Courts and commentators, however, have failed to clarify that concept of strict liability has different meanings in different contexts, and it is necessary to take into account correct paradigm(6) of to properly interpret CERCLA. The term strict liability can refer either to for criminal offenses and civil public welfare offenses, or to in tort for or abnormally dangerous activities.(7) In context of for criminal offenses and civil public welfare offenses, definition of is limited to concept of mens rea, or mental element of a crime or infraction.(8) Under this paradigm, applies to commission of a prohibited act, regardless of mental state of defendant.(9) Strict in tort for highly hazardous activities is similar to for criminal and public welfare offense because proof of a defendant's mental state, such as intent or negligence, is not required for liability. However, tort concept of for ultrahazardous activity also encompasses important concepts of that make it a significantly different conceptual paradigm.(10) Most importantly, inquiry in context of for ultrahazardous activity focuses on harm that flows from an instrumentality, as opposed to harm from conduct of a specific individual defendant.(11) A defendant's is based on defendant's relationship to instrumentality, such as being owner, operator or user.(12) In addition, a plaintiff establishing tort for ultrahazardous activity may recover damages for all harm that is caused by dangerous instrumentality, as long as it is of type that made instrumentality ultrahazardous in first place.(13) A proximate causation analysis, to extent applicable at all, does not include a requirement that harm was foreseeable based on a particular defendant's vantage point, as in negligence law.(14) Strict for ultrahazardous activity also has a unique approach regarding intervening causes such as third parties and acts of God.(15) Litigants have, on occasion, advanced concept of as a basis to explain nature of CERCLA causation, but some courts and commentators have mistakenly responded that only relates to mens rea and is irrelevant to causation.(16) These courts and commentators have failed to clarify that CERCLA's structure is derived in large measure from tort paradigm of for ultrahazardous activity, not from criminal/civil public welfare offense paradigm, and have incorrectly conceptualized CERCLA in terms of activity of an individual defendant.(17) Thus, rather than viewing basis of as a relationship between defendant and an instrumentality that causes harm (the CERCLA vessel or facility), some courts have required a showing that an individual defendant's acts caused harm in form of cleanup costs or natural resource damages. …