For the purpose of this chapter, the following terms have the meanings given below:

(1) "Director" means the director of the department of ecology or the director's designee.

(2) "Hazardous substance" means anything designated as such by the provisions of this rule, as adopted and thereafter amended. In addition, this term includes:

(a) Any substance that, on March 1, 1989, is a hazardous substance under section 101(14) of the Federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA), as amended by P.L. 99-499. These substances consist of chemicals and elements in their purest form. (Reportable quantities associated with these chemicals under CERCLA are not considered for the purposes of this tax, but are duly noted here to avoid any confusion regarding the intent of the federal regulation. See CERCLA, 42 USCA, Sec. 9601.) A CERCLA substance which contains water, a stabilizer, or a preservative is still considered pure. Combinations of CERCLA substances as ingredients together with nonhazardous substances will not be taxable unless the end product is specifically designated as a hazardous substance by the department of ecology under the provisions of this rule;

(b) Petroleum products;

(c) Pesticide products required to be registered under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

(3) "Material" means substance, chemicals, category of chemicals, or mixtures of chemicals including products.

(4) "Persistence" means the tendency of a substance to resist degradation and remain in the atmosphere, soil, and/or water.

(5) "Toxicity" means a measure of the propensity of a chemical to produce injury once it reaches a susceptible receptor in or on a living organism.

(6) Except for terms defined in this section, the definitions in section 9, chapter 2, Laws of 1989 and WAC 458-20-252 apply to this chapter.