In this subchapter:
(1) "Contaminant" has the meaning assigned by Section 361.601.
(2) "Innocent owner or operator" means a person that:
(A) is an owner or operator of property that has become contaminated as a result of a release or migration of contaminants from a source or sources not located on or at the property; and
(B) did not cause or contribute to the source or sources of the contamination referred to in Paragraph (A).