Cal. Health & Safety Code § 25223

(a) A person may apply to the department for a written variance from a land use restriction imposed by the department. An application shall contain sufficient evidence for the department to issue a notice for a hearing. The notice shall contain both of the following:
1. (1) A statement of all of the following that apply:
  1. (A) Land use restrictions have been imposed on the land.
  2. (B) A hearing is pending on the land.
2. (2) A statement of who is applying for a variance, the proposed variance, and a statement of the reasons in support of the granting of a variance.
(b) The procedures for the conducting of the hearing specified in subdivision (a) are those set forth in former Article 11 (commencing with Section 25220) of Chapter 6.5 of Division 20. A person shall not make a subsequent application pursuant to this section within 18 months of a final decision on an application by the department. A person applying for a variance pursuant to this section shall pay the department for all costs incurred by the department relating to the application.
(c) The applicant shall have the burden of proving at the hearing that the variance will not cause or allow any of the following effects associated with hazardous waste or extremely hazardous waste:
1. (1) The creation or increase of significant present or future hazards to public health.
2. (2) A significant diminution of the ability to mitigate any significant potential or actual hazard to public health.
3. (3) A long-term increase in the number of humans or animals exposed to significant hazards that affect the health, well-being, or safety of the public.
(d) If, upon the preponderance of the testimony taken, the director is of the opinion that the variance should be granted, the director shall issue and cause to be served his or her decision and findings of fact on the owner of the land, the legislative body of the city or county in whose jurisdiction the land is located, and upon any other persons who were permitted to intervene in the proceedings. The findings of fact shall include the exact nature of the proposed variance and the reasons in support of the granting of the variance.
(e) If the director is of the opinion that the variance should not be granted, the director shall issue and cause to be served his or her findings of fact in support of the denial on the parties specified in subdivision (d).
(f) The department shall record within 10 days any final decision made by the director pursuant to this section as provided in Section 25225.
(g) A decision of the director made after a hearing held pursuant to this section shall be reviewable pursuant to Section 1094.5 of the Code of Civil Procedure and shall be upheld if the court finds that it is supported by substantial evidence.