Scope of review

Section 706 of title 5, United States Code, is amended— (1) in the first sentence of the matter preceding paragraph (1)— (A) by striking agency action. and inserting agency action. If a statute that an agency administers is silent or ambiguous as to the proper construction of a particular term or provision or set of terms or provisions, and an agency has followed the applicable procedures in subchapter II of chapter 5, has otherwise lawfully adjudicated a matter, or has followed the corresponding procedural provisions of the relevant statute, as applicable, a reviewing court shall defer to the agency’s reasonable or permissible interpretation of that statute, regardless of the significance of the related agency action or a possible future agency action.; and (B) by striking To the extent necessary and inserting: (a) In general To the extent necessary; and (2) by adding at the end the following: (b) Unreasonable delay For purposes of subsection (a)(1), unreasonable delay shall include— (1) when an agency has not issued a notice of proposed rulemaking before the date that is 1 year after the date of enactment of the legislation mandating the rulemaking, where no deadline for the rulemaking was specified in the enacted law; (2) when an agency has not issued a final version of a proposed rule before the date that is 1 year after the date on which the proposed rule was published in the Federal Register; (3) when an agency has not implemented a final rule before the date that is 1 year after the implementation date published in the Federal Register or, if no implementation date was provided, before the date that is 1 year after the date on which the final rule was published in the Federal Register; and (4) when an agency has not issued or implemented a final rule, upon a showing of good cause therefor..