Cal. Health & Safety Code § 25205.5
(a)
(4) For purposes of calculating the amount of the fee imposed pursuant to paragraph (1), a generator of hazardous waste that is issued a hazardous waste facilities permit from the department and that pays the annual facility fee, as specified in Section 25205.2, may deduct, from the amount of hazardous waste otherwise subject to this subdivision that is generated per calendar year, the amount of hazardous waste that is stored, bulked, and transferred solely through the location of the permitted hazardous waste facility and that is in route to another facility that is authorized to do any of the following: