“Response,” “respond,” or “response action” have the same meanings as defined in Section 9601(25) of the federal act (42 U.S.C. Sec. 9601(25)). The enforcement and oversight activities of the department and regional board are included within the meaning of “response,” “respond,” or “response action.”
Source:
Section 25323.3, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=HSC§ionNum=25323.3..