California Code, Health and Safety Code - HSC § 25299.41

For the purpose of implementing this chapter, every owner of an underground storage tank for which a permit is required pursuant to Section 25284 shall pay a storage fee of six mills ($0.006) for each gallon of petroleum placed in an underground storage tank that the person owns. The fee imposed pursuant to this section shall be paid to the California Department of Tax and Fee Administration pursuant to Part 26 (commencing with Section 50101) of Division 2 of the Revenue and Taxation Code.