(1) The Workers' Compensation Commission shall collect a tax from every self-insured employer at a rate to be determined as provided by § 11-9-306 but not to exceed three percent (3%) of the written manual premium which would have to be paid under § 11-9-303 by a carrier if the self-insured employer were insured by a carrier.
(2) Upon the final payment of the liabilities of the Death and Permanent Total Disability Trust Fund pursuant to § 11-9-502, the tax rate under this section shall not exceed one and five-tenths percent (1.5%).
(3) If the tax provided for under this section is not paid within thirty (30) days of the date provided in § 11-9-306, there shall be assessed a penalty for each thirty (30) days the amount so assessed remains unpaid which is equal to ten percent (10%) of the unpaid amounts and which shall be collected at the same time as a part of the tax assessed.