(1) The department may adopt rules as necessary for the purpose of implementing, administering, and enforcing this chapter.

(2)(a) The department must adopt rules to implement the determinations of regulatory actions specified in RCW 70A.350.040(1) (b) or (c). When proposing or adopting rules to implement regulatory determinations specified in this subsection, the department must identify the expected costs and benefits of the proposed or adopted rules to state agencies to administer and enforce the rules and to private persons or businesses, by category of type of person or business affected.

(b) A rule adopted to implement a regulatory determination involving a restriction on the manufacture, wholesale, distribution, sale, retail sale, or use of a priority consumer product containing a priority chemical may take effect no sooner than three hundred sixty-five days after the adoption of the rule.

(c) Each rule adopted to implement a determination of regulatory action specified in RCW 70A.350.040(1) (b) or (c) is a significant legislative rule for purposes of RCW 34.05.328. The department must prepare a small business economic impact statement consistent with the requirements of RCW 19.85.040 for each rule to implement a determination of a regulatory action specified in RCW 70A.350.040(1) (b) or (c).