(1) The department must periodically assess the availability of, and methodology used by, the United States centers for disease control and the agency for toxic substances and disease registry's social vulnerability index, as compared to how it existed as of January 1, 2025.

(2) If the department determines that the social vulnerability index is no longer available in substantially the same form as it existed on January 1, 2025, the department must notify each registered producer responsibility organization that for purposes of the identification of socially vulnerable populations under this chapter, the department and producer responsibility organizations are no longer required to reference the United States centers for disease control and the agency for toxic substances and disease registry's social vulnerability index. Instead, the department and registered producer responsibility organizations must reference the alternative populations specified in subsection (3) of this section.

(3)(a) Until such time as a rule is adopted under (b) of this subsection, the department and registered producer responsibility organizations must, for purposes of identifying socially vulnerable populations, identify as socially vulnerable populations those communities ranked as an eight or higher on the environmental health disparities map developed under RCW 43.70.815.

(b) After making a determination under subsection (2) of this section, by rule the department may, but is not required to, adopt an alternative methodology for the identification of socially vulnerable populations to replace the reference to the United States centers for disease control and the agency for toxic substances and disease registry's social vulnerability index. A rule adopted under this subsection may, but is not required to, rely in whole or in part on the environmental health disparities map developed by the department of health under RCW 43.70.815.