(a) The Dallas County Commission may impose an additional excise tax on persons selling, distributing, storing, or withdrawing from storage gasoline and motor fuel in an amount not to exceed two cents ($0.02) and may require every distributor, retail dealer, or storer to pay the additional excise tax. The additional excise tax imposed pursuant to this part shall not be imposed upon the sale of gasoline or motor fuel used in interstate commerce. If the additional excise tax has been paid by a distributor, retail dealer, or storer, the payment shall be sufficient, the intention being that the taxes shall not be paid but once. The additional excise tax shall apply to persons, retail, dealers, or distributors storing gasoline or motor fuel and distributing or withdrawing from storage, whether the withdrawal is for sale or other use. Sellers of gasoline or motor fuel paying the tax herein provided may pay the tax computed and paid on the basis of sales, and storers and distributors shall compute and pay the tax on the basis of withdrawals or distributions. The commission shall not impose any tax upon any gasoline or motor fuel when used in essential governmental functions by the State of Alabama or any agency thereof, federal government or any agency thereof, county commissions, or boards of education. The taxes may only be imposed by the commission after two public hearings have been held on the proposed taxes held at least one week apart. The public hearings shall be advertised for three consecutive days prior to each hearing. After the public hearings, the taxes may be imposed pursuant to this section at a regular or special call meeting of the commission upon the adoption by the commission of a resolution by a majority vote of the total membership.

(b) Any user exempted from the state gasoline tax or motor fuel tax, or both, shall be exempted from the tax levied in this part.