California Code, Revenue and Taxation Code - RTC § 50109

The fee collected under Section 50108 is due and payable to the board quarterly on or before the 25th day of the month following the end of each calendar quarter. Each feepayer, on or before the 25th day of the month following the quarterly period for which the fee is due, shall prepare a fee return for the preceding quarterly period, in the form as prescribed by the board, which may include, but not be limited to, electronic media showing the total number of gallons of petroleum placed into underground storage tanks which he or she owns during the period, the amount of the fee for the period covered by the return, and any other information that the board determines to be necessary. The feepayer shall deliver the return, together with a remittance of the amount of the fee due, to the office of the board on or before the 25th day of the month following the quarterly period for which the fee is due.Returns shall be authenticated in a form or pursuant to methods as may be prescribed by the board.