[Code of Federal Regulations]
[Title 40, Volume 25]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR403.18]

[Page 47-48]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 403--GENERAL PRETREAT- MENT REGULATIONS FOR EXISTING AND NEW SOURCES OF POLLUTION--Table of Contents
 
Sec. 403.18  Modification of POTW pretreatment programs.

    (a) General. Either the Approval Authority or a POTW with an 
approved POTW Pretreatment Program may initiate program modification at 
any time to reflect changing conditions at the POTW. Program 
modification is necessary whenever there is a significant change in the 
operation of a POTW Pretreatment Program that differs from the 
information in the POTW's submission, as approved under Sec. 403.11.
    (b) Substantial modifications defined. Substantial modifications 
include:
    (1) Modifications that relax POTW legal authorities (as described in 
Sec. 403.8(f)(1)), except for modifications that directly reflect a 
revision to this Part 403 or to 40 CFR chapter I, subchapter N, and are 
reported pursuant to paragraph (d) of this section;
    (2) Modifications that relax local limits, except for the 
modifications to local limits for pH and reallocations of the Maximum 
Allowable Industrial Loading of a pollutant that do not increase the 
total industrial loadings for the pollutant, which are reported pursuant 
to paragraph (d) of this section. Maximum Allowable Industrial Loading 
means the total mass of a pollutant that all Industrial Users of a POTW 
(or

[[Page 48]]

a subgroup of Industrial Users identified by the POTW) may discharge 
pursuant to limits developed under Sec. 403.5(c);
    (3) Changes to the POTW's control mechanism, as described in 
Sec. 403.8(f)(1)(iii);
    (4) A decrease in the frequency of self-monitoring or reporting 
required of industrial users;
    (5) A decrease in the frequency of industrial user inspections or 
sampling by the POTW;
    (6) Changes to the POTW's confidentiality procedures; and
    (7) Other modifications designated as substantial modifications by 
the Approval Authority on the basis that the modification could have a 
significant impact on the operation of the POTW's Pretreatment Program; 
could result in an increase in pollutant loadings at the POTW; or could 
result in less stringent requirements being imposed on Industrial Users 
of the POTW.
    (c) Approval procedures for substantial modifications. (1) The POTW 
shall submit to the Approval Authority a statement of the basis for the 
desired program modification, a modified program description (see 
Sec. 403.9(b)), or such other documents the Approval Authority 
determines to be necessary under the circumstances.
    (2) The Approval Authority shall approve or disapprove the 
modification based on the requirements of Sec. 403.8(f) and using the 
procedures in Sec. 403.11(b) through (f), except as provided in 
paragraphs (c) (3) and (4) of this section. The modification shall 
become effective upon approval by the Approval Authority.
    (3) The Approval Authority need not publish a notice of decision 
under Sec. 403.11(e) provided: The notice of request for approval under 
Sec. 403.11(b)(1) states that the request will be approved if no 
comments are received by a date specified in the notice; no substantive 
comments are received; and the request is approved without change.
    (4) Notices required by Sec. 403.11 may be performed by the POTW 
provided that the Approval Authority finds that the POTW notice 
otherwise satisfies the requirements of Sec. 403.11.
    (d) Approval procedures for non-substantial modifications. (1) The 
POTW shall notify the Approval Authority of any non-substantial 
modification at least 45 days prior to implementation by the POTW, in a 
statement similar to that provided for in paragraph (c)(1) of this 
section.
    (2) Within 45 days after the submission of the POTW's statement, the 
Approval Authority shall notify the POTW of its decision to approve or 
disapprove the non-substantial modification.
    (3) If the Approval Authority does not notify the POTW within 45 
days of its decision to approve or deny the modification, or to treat 
the modification as substantial under paragraph (b)(7) of this section, 
the POTW may implement the modification.
    (e) Incorporation in permit. All modifications shall be incorporated 
into the POTW's NPDES permit upon approval. The permit will be modified 
to incorporate the approved modification in accordance with 40 CFR 
122.63(g).

[62 FR 38414, July 17, 1997]