Except as provided in subsection (b), before promulgating any rule for which a written statement is required under section 1532 of this title, the agency shall identify and consider a reasonable number of regulatory alternatives and from those alternatives select the least costly, most cost-effective or least burdensome alternative that achieves the objectives of the rule, for-
(1) State, local, and tribal governments, in the case of a rule containing a Federal intergovernmental mandate; and
(2) the private sector, in the case of a rule containing a Federal private sector mandate.
The provisions of subsection (a) shall apply unless-
(1) the head of the affected agency publishes with the final rule an explanation of why the least costly, most cost-effective or least burdensome method of achieving the objectives of the rule was not adopted; or
(2) the provisions are inconsistent with law.
No later than 1 year after March 22, 1995, the Director of the Office of Management and Budget shall certify to Congress, with a written explanation, agency compliance with this section and include in that certification agencies and rulemakings that fail to adequately comply with this section.
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