(a) Except as provided in subsection (b) of this Code section, sales of motor fuels as defined in paragraph (9) of Code Section 48-9-2 shall be exempt from the first 3 percent of the sales and use taxes levied or imposed by this article and shall be subject to the remaining 1 percent of the sales and use taxes levied or imposed by this article.

(b) Sales of motor fuel other than gasoline which motor fuel other than gasoline is purchased for purposes other than propelling motor vehicles on public highways as defined in Article 1 of Chapter 9 of this title shall be fully subject to the 4 percent sales and use taxes levied or imposed by this article unless otherwise specifically exempted by this article.

(c) It is specifically declared to be the intent of the General Assembly that taxation imposed on sales of motor fuel wholly or partially subject to taxation under this Code section shall not constitute motor fuel taxes for purposes of any provision of the Constitution providing for the automatic or mandatory appropriation of any amount of funds equal to funds derived from motor fuel taxes.