(a) Notwithstanding any other provision of law, except as provided in this article, any hazardous waste restricted from land disposal by the federal act, or by the Environmental Protection Agency pursuant to the federal act, or by the department pursuant to Section 25179.6, is prohibited from land disposal in the state, unless one of the following circumstances apply:

1. (1) The hazardous waste, or the producer of the hazardous waste is granted a variance, extension, exclusion, or exemption by the administrator of the Environmental Protection Agency or by the department.
2. (2) The waste is treated in accordance with an applicable treatment standard.
3. (3) The federal restriction is stayed or otherwise conditioned by an appropriate court of law.
4. (4) It is a solid hazardous waste generated in the cleanup or decontamination of any site contaminated only by hazardous waste that has not been restricted or prohibited by the federal act or prohibited by the Environmental Protection Agency pursuant to the federal act, and which does not meet the treatment standards established by the department pursuant to Section 25179.6, if the department or other federal, state, or local agency with authority to approve the cleanup or decontamination has approved the disposal of the waste.

(b)

1. (1) Any treatment standard that is adopted or amended by the Environmental Protection Agency pursuant to subsection (m) of Section 6924 of the federal act, for a hazardous waste prohibited from land disposal pursuant to subdivision (a) and that is in effect, is the treatment standard required to be met before the hazardous waste may be disposed of, using land disposal, in the state. Any land disposal restriction, including any treatment standard, notification requirement, or recordkeeping requirement that is adopted or amended by the Environmental Protection Agency shall become effective in the state upon the effective date of that adoption or amendment, as specified in the final rule published in the Federal Register, and shall, as of that date, supersede any corresponding land disposal restriction specified in the department’s regulations, unless one or more of the following conditions exist:

   1. (A) A more stringent statutory requirement is applicable.
   2. (B) A land disposal restriction previously adopted by the department expressly states, in that regulation, that the land disposal restriction is intended to supersede any less stringent land disposal restrictions which may be subsequently adopted by the Environmental Protection agency.
   3. (C) The department subsequently adopts a more stringent land disposal restriction pursuant to subdivision (c) of Section 25179.6.
2. (2) Except as provided in Section 25179.6, any extension, variance, or exemption from the treatment standard granted by the Administrator of the Environmental Protection Agency shall also apply in this state.