Oklahoma law, 27A O.S. Supp. Section 1-1-202 (enacted through Senate Bill 549) mandates that each state environmental agency shall promulgate, by July 1, 2001, a Water Quality Standards Implementation Plan (WQSIP) for its jurisdictional areas of environmental responsibility. The Plan must be developed in compliance with the Administrative Procedures Act. After initial promulgation, the Department must review its plan at least every three years thereafter to determine whether revisions are necessary.
Okla. Admin. Code § 460:12-1-2