(1) In addition to regulatory fees, each auto transportation company must pay mileage fees on each vehicle it operates with a seating capacity over six passengers. RCW 46.16.125 establishes the following mileage fees:

(a) Fifteen cents for each one hundred vehicle miles; or

(b) Twenty cents for each one hundred vehicle miles if the vehicle is propelled by steam, electricity, natural gas, diesel oil, butane, or propane.

(2) The commission transmits mileage fees collected under the provisions of RCW 46.16.125 to the state treasurer to be deposited in the motor vehicle fund.

(3) If a company fails to pay the mileage fees, the company is subject to a penalty of one hundred percent of the payment due.