IPR SWTPs shall include, at a minimum, a combination of a chlorine disinfection system designed to comply with OAC 252:656-21-2 and an ultraviolet radiation disinfection system designed to comply with OAC 252:656-21-3, or an approvable equivalent, in order to comply with the requirements outlined in Subchapter 3 of this Chapter. Other disinfection systems will also be considered, provided that the overall design consists of multiple barriers and achieves the disinfection requirements outlined in Subchapter 3 of this Chapter.
Okla. Admin. Code § 252:628-5-7