In section 518(e) of the Clean Water Act (CWA), Congress authorized EPA to treat eligible federally recognized Indian tribes in a similar manner as states for purposes of administering section 303 and certain other provisions of the CWA, and directed the agency to promulgate regulations effectuating this authorization. EPA has issued regulations establishing a process for federally recognized tribes to obtain treatment in a similar manner as states (TAS) for several provisions of the CWA; 50 tribes, for example, have obtained TAS authority to issue water quality standards under CWA section 303(c). EPA, however, has not yet promulgated regulations expressly establishing a process for such tribes to obtain TAS authority to administer the water quality restoration provisions of CWA section 303(d), including issuing lists of impaired waters and developing total maximum daily loads (TMDLs) under CWA section 303(d), as states routinely do. EPA is now proposing to remedy this gap. By establishing regulatory procedures for eligible tribes to obtain TAS for the CWA Section 303(d) Impaired Water Listing and TMDL Program, the proposed rule would enable eligible tribes to obtain authority to identify impaired waters on their reservations and to establish TMDLs, which serve as plans for attaining and maintaining applicable water quality standards (WQS). The proposal is comparable to similar regulations that EPA issued in the 1990s for the CWA Section 303(c) WQS and CWA Section 402 and 404 Permitting Programs, and includes features designed to minimize paperwork and unnecessary reviews. EPA requests comments on all aspects of the proposed rule.