Solid wastes that designate as dangerous waste or extremely hazardous waste but do not designate as hazardous waste under federal law are conditionally exempt from the requirements of this chapter, if:

(1) The waste is generated pursuant to a consent decree issued under chapter 70A.305 RCW;

(2) The consent decree characterizes the solid waste and specifies management practices and a department-approved treatment or disposal location;

(3) The management practices are consistent with RCW 70A.300.260 and are protective of human health and the environment as determined by the department of ecology; and

(4) Waste treated or disposed of on-site will be managed in a manner determined by the department to be as protective of human health and the environment as clean-up standards pursuant to chapter 70A.305 RCW.

This section shall not be interpreted to limit the ability of the department to apply any requirement of this chapter through a consent decree issued under chapter 70A.305 RCW, if the department determines these requirements to be appropriate. Neither shall this section be interpreted to limit the application of this chapter to a cleanup conducted under the federal comprehensive environmental response, compensation, and liability act (42 U.S.C. Sec. 9601 et seq., as amended).