P pursuant to 33 U.S.C. § 1369(b) (1), sought review of the procedures employed by D in deferring indefinitely the effective date of a set of amendments to regulations dealing with the discharge of toxic pollutants into publicly owned treatment works (POTWs). The regulations and amendments were promulgated under section 307(b) (1) of the Clean Water Act, 33 U.S.C. § 1317(b) (1), which provides: The Administrator shall, within one hundred and eighty days after October 18, 1972, and from time to time thereafter, publish proposed regulations establishing pretreatment standards for the introduction of pollutants into treatment works . . . which are publicly owned for those pollutants which are determined not to be susceptible to treatment by such treatment works or which would interfere with the operation of such treatment works. Not later than ninety days after such publication, and after the opportunity for a public hearing, the Administrator shall promulgate such pretreatment standards. Pretreatment standards under this subsection shall specify a time for compliance not to exceed three years from the date of promulgation and shall be established to prevent the discharge of any pollutants through treatment works . . . which are publicly owned, which pollutant interferes with, passes through, or otherwise is incompatible with such works. On February 2, 1977, D proposed a rule for the pretreatment standards. On June 26, 1978, after more than a year of consideration, 4 public hearings and 16 public meetings were held and more than 400 individual comments were received, D promulgated the final regulations. On February 2, 1977, D proposed a rule for the pretreatment standards. They became effective on August 28, 1978. On October 29, 1979, D proposed a set of amendments to the 1978 regulations and promulgated those amendments on January 28, 1981, in 'final form.' D designated March 13, 1981, as the effective date of the amendments, and, established February 10, 1981, as the date of the regulations 'for the purposes of judicial review.' On January 29, 1981, the President of the United States issued a memorandum ordering that the effective dates of all regulations which were final but not yet effective be postponed for a period of sixty days from the date of the memorandum. The effective date was postponed from March 13, 1981, to March 30, 1981. On February 17, 1981, the President issued Executive Order 12291 that no action should be taken unless the potential benefits of the regulatory action would outweigh the costs to society, that the agency should maximize the net benefits to society by its regulatory action, that the agency should choose the regulatory action involving the least net cost to society, and that the agency action should maximize the 'aggregate net benefits to society, taking into account the condition of the particular industries affected by regulations, the condition of the national economy, and other regulatory actions contemplated for the future.' D was to suspend or postpone the effective dates of all major rules that they have promulgated in final form as of the date of this Order, but that have not yet become effective, excluding major rules that cannot legally be postponed or suspended and major rules that, for good cause, ought to become effective as final rules without reconsideration. D signed an order on March 27, 1981, which was published in the Federal Register of April 2, 1981, eliminating the March 30, 1981, effective date of the amendments and postponing them indefinitely. That action was 'taken pursuant to Executive Order 12291.' This was the sole reason given for the postponement. On June 24, 1981, P filed suit under § 1369(b) (1) seeking a review of D's action in deferring the amendments indefinitely without holding an APA notice and comment period. P challenges the failure of D to comply with APA notice and comment procedures when it indefinitely postponed the amendments.