(a) The commission may issue a standard permit under the procedures in §116.603 of this title (relating to Public Participation in Issuance of Standard Permits) if the commission finds that:(1) the standard permit is enforceable; and(2) the commission can adequately monitor compliance with the terms of the standard permit.(b) The commission may issue standard permits for:(1) grandfathered facilities. Standard permits for use by grandfathered facilities before September 1, 2001 are not required to meet best available control technology;(2) the installation of emission control equipment that constitutes a modification or a new facility under TCAA, §382.057.(c) Other than the standard permits issued for use under subsection (b)(1) and (2) of this section, all standard permits issued by the commission under this chapter shall require best available control technology.