Page:United States Statutes at Large Volume 101 Part 1.djvu/97

 PUBLIC LAW 100-4—FEB. 4, 1987

101 STAT. 67

"(4) APPROVAL OF MAJOR COMPONENT PARTIAL PERMIT PRO-

GRAMS.—The Administrator may approve under this subsection a partial and phased permit program covering administration of ' a major component (including discharge categories) of a State permit program required by subsection (b) if— "(A) the Administrator determines that the partial program represents a significant and identifiable part of the State program required by subsection (b); and "(B) the State submits, and the Administrator approves, a '" plan for the State to assume administration by phases of the remainder of the State program required by subsection (b) by a specified date not more than 5 years after submission of the partial program under this subsection and agrees to make all reasonable efforts to assume such administration by such date.". (b) RETURN OF STATE PERMIT PROGRAM TO ADMINISTRATOR.—

(1) IN GENERAL.—Section 402(c) is amended by adding at the 33 USC 1342. end thereof the following new paragraph: "(4) LIMITATIONS ON PARTIAL PERMIT PROGRAM RETURNS AND

WITHDRAWALS.—A State may return to the Administrator administration, and the Administrator may withdraw under paragraph (3) of this subsection approval, of— "(A) a State partial permit program approved under subsection (n)(3) only if the entire permit program being administered by the State department or agency at the time is returned or withdrawn; and "(B) a State partial permit program approved under subsection (n)(4) only if an entire phased component of the permit program being administered by the State at the time is returned or withdrawn.".

Ante, p. 66.

(2) CONFORMING AMENDMENT.—Section 402(c)(1) is amended

by striking out "as to those navigable waters" and inserting in lieu thereof "as to those discharges". SEC. 404. ANTI-BACKSLIDING.

(a) GENERAL RULE.—Section 402 is amended by adding at the end thereof the following new subsection:

Ante, p. 66.

"(o) ANTI-BACKSLIDING.— "(1) GENERAL PROHIBITION.—In the case of effluent limitations

established on the basis of subsection (a)(1)(B) of this section, a permit may not be renewed, reissued, or modified on the basis of effluent guidelines promulgated under section 3040t>) subsequent to the original issuance of such permit, to contain effluent s limitations which are less stringent than the comparable effluent limitations in the previous permit. In the case of effluent - limitations established on the basis of section 301(b)(1)(C) or section 303(d) or (e), a permit may not be renewed, reissued, or ? • modified to contain effluent limitations which are less stringent than the comparable effluent limitations in the previous permit except in compliance with section 303(d)(4). "(2) EXCEPTIONS.—A permit with respect to which paragraph (1) applies may be renewed, reissued, or modified to contain a less stringent effluent limitation applicable to a pollutant if— "(A) material and substantial alterations or additions to the permitted facility occurred after permit issuance which justify the application of a less stringent effluent limitation;

33 USC 1314.

33 USC 1311. 33 USC 1313.

Pollution.

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