On page 2 of SB 1591, add a new subsection (f) to read as follows: (f) Any facility that emits air pollutants that was in existence on or before September 1, 1971 and is operating without a construction permit issued by the commission is not eligible for the type of exemption which the commission is authorized to grant under Subsection (a) of this section unless the proposed alternative method of pollution control will result in a decrease in actual air emissions from that facility.