Sec. 30. (a) Sales of tangible personal property are exempt from the state gross retail tax if:
(1) the property constitutes, is incorporated into, or is consumed in the operation of, a device, facility, or structure predominantly used and acquired for the purpose of complying with any state, local, or federal environmental quality statutes, regulations, or standards; and
(2) the person acquiring the property is engaged in the business of manufacturing, processing, refining, mining, recycling (as defined in section 45.8 of this chapter), or agriculture.
(b) The portion of the sales price of tangible personal property which is exempt from state gross retail and use taxes under this section equals the product of:
(1) the total sales price; multiplied by
(2) one hundred percent (100%).