[Code of Federal Regulations]
[Title 40, Volume 18]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR125.3]

[Page 285-288]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 125--CRITERIA AND STANDARDS FOR THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM--Table of Contents
 
    Subpart A--Criteria and Standards for Imposing Technology-Based 
     Treatment Requirements Under Sections 301(b) and 402 of the Act
 
Sec. 125.3  Technology-based treatment requirements in permits.

    (a) General. Technology-based treatment requirements under section 
301(b) of the Act represent the minimum level of control that must be 
imposed in a permit issued under section 402 of the Act. (See 
Secs. 122.41, 122.42 and 122.44 for a discussion of additional or more 
stringent effluent limitations and conditions.) Permits shall contain 
the following technology-based treatment requirements in accordance with 
the following statutory deadlines;
    (1) For POTW's, effluent limitations based upon:
    (i) Secondary treatment--from date of permit issuance; and
    (ii) The best practicable waste treatment technology--not later than 
July 1, 1983; and
    (2) For dischargers other than POTWs except as provided in 
Sec. 122.29(d), effluent limitations requiring:
    (i) The best practicable control technology currently available 
(BPT)--
    (A) For effluent limitations promulgated under Section 304(b) after 
January 1, 1982 and requiring a level of control substantially greater 
or based on fundamentally different control technology than under 
permits for an industrial category issued before such date, compliance 
as expeditiously as practicable but in no case later than three years 
after the date such limitations are promulgated under section 304(b) and 
in no case later than March 31, 1989;
    (B) For effluent limitations established on a case-by-case basis 
based on Best Professional Judgment (BPJ) under Section 402(a)(1)(B) of 
the Act in a permit issued after February 4, 1987, compliance as 
expeditiously as practicable but in no case later than three years after 
the date such limitations are established and in no case later than 
March 31, 1989;
    (C) For all other BPT effluent limitations compliance is required 
from the date of permit issuance.

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    (ii) For conventional pollutants, the best conventional pollutant 
control technology (BCT)--
    (A) For effluent limitations promulgated under section 304(b), as 
expeditiously as practicable but in no case later than three years after 
the date such limitations are promulgated under section 304(b), and in 
no case later than March 31, 1989.
    (B) For effluent limitations established on a case-by-case (BPJ) 
basis under section 402(a)(1)(B) of the Act in a permit issued after 
February 4, 1987, compliance as expeditiously as practicable but in no 
case later than three years after the date such limitations are 
established and in no case later than March 31, 1989;
    (iii) For all toxic pollutants referred to in Committee Print No. 
95-30, House Committee on Public Works and Transportation, the best 
available technology economically achievable (BAT)--
    (A) For effluent limitations established under section 304(b), as 
expeditiously as practicable but in no case later than three years after 
the date such limitations are promulgated under section 304(b), and in 
no case later than March 31, 1989.
    (B) For permits issued on a case-by-case (BPJ) basis under section 
402(a)(1)(B) of the Act after February 4, 1987 establishing BAT effluent 
limitations, compliance is required as expeditiously as practicable but 
in no case later than three years after the date such limitations are 
promulgated under section 304(b), and in no case later than March 31, 
1989.
    (iv) For all toxic pollutants other than those listed in Committee 
Print No. 95-30, effluent limitations based on BAT--
    (A) For effluent limitations promulgated under section 304(b) 
compliance is required as expeditiously as practicable, but in no case 
later than three years after the date such limitations are promulgated 
under section 304(b) and in no case later than March 31, 1989.
    (B) For permits issued on a case-by-case (BPJ) basis under Section 
402(a)(1)(B) of the Act after February 4, 1987 establishing BAT effluent 
limitations, compliance is required as expeditiously as practicable but 
in no case later than 3 years after the date such limitations are 
established and in no case later than March 31, 1989.
    (v) For all pollutants which are neither toxic nor conventional 
pollutants, effluent limitations based on BAT--
    (A) For effluent limitations promulgated under section 304(b), 
compliance is required as expeditiously as practicable but in no case 
later than 3 years after the date such limitations are established and 
in no case later than March 31, 1989.
    (B) For permits issued on a case-by-case (BPJ) basis under section 
402(a)(1)(B) of the Act after February 4, 1987 establishing BAT effluent 
limitations compliance is required as expeditiously as practicable but 
in no case later than three years after the date such limitations are 
established and in no case later than March 31, 1989.
    (b) Statutory variances and extensions. (1) The following variances 
from technology-based treatment requirements are authorized by the Act 
and may be applied for under Sec. 122.21;
    (i) For POTW's, a section 301(h) marine discharge variance from 
secondary treatment (subpart G);
    (ii) For dischargers other than POTW's;
    (A) A section 301(c) economic variance from BAT (subpart E);
    (B) A section 301(g) water quality related variance from BAT 
(subpart F); and
    (C) A section 316(a) thermal variance from BPT, BCT and BAT (subpart 
H).
    (2) The following extensions of deadlines for compliance with 
technology-based treatment requirements are authorized by the Act and 
may be applied for under Sec. 124.53:
    (i) For POTW's a section 301(i) extension of the secondary treatment 
deadline (subpart J);
    (ii) For dischargers other than POTW's:
    (A) A section 301(i) extension of the BPT deadline (subpart J); and
    (B) A section 301(k) extension of the BAT deadline (subpart C).
    (c) Methods of imposing technology-based treatment requirements in 
permits. Technology-based treatment requirements may be imposed through 
one of the following three methods:

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    (1) Application of EPA-promulgated effluent limitations developed 
under section 304 of the Act to dischargers by category or subcategory. 
These effluent limitations are not applicable to the extent that they 
have been remanded or withdrawn. However, in the case of a court remand, 
determinations underlying effluent limitations shall be binding in 
permit issuance proceedings where those determinations are not required 
to be reexamined by a court remanding the regulations. In addition, 
dischargers may seek fundamentally different factors variances from 
these effluent limitations under Sec. 122.21 and subpart D of this part.
    (2) On a case-by-case basis under section 402(a)(1) of the Act, to 
the extent that EPA-promulgated effluent limitations are inapplicable. 
The permit writer shall apply the appropriate factors listed in 
Sec. 125.3(d) and shall consider:
    (i) The appropriate technology for the category or class of point 
sources of which the applicant is a member, based upon all available 
information; and
    (ii) Any unique factors relating to the applicant.

[Comment: These factors must be considered in all cases, regardless of 
whether the permit is being issued by EPA or an approved State.]

    (3) Through a combination of the methods in paragraphs (d) (1) and 
(2) of this section. Where promulgated effluent limitations guidelines 
only apply to certain aspects of the discharger's operation, or to 
certain pollutants, other aspects or activities are subject to 
regulation on a case-by-case basis in order to carry out the provisions 
of the Act.
    (4) Limitations developed under paragraph (d)(2) of this section may 
be expressed, where appropriate, in terms of toxicity (e.g., ``the 
LC50 for fat head minnow of the effluent from outfall 001 
shall be greater than 25%''). Provided, That is shown that the limits 
reflect the appropriate requirements (for example, technology-based or 
water-quality-based standards) of the Act.
    (d) In setting case-by-case limitations pursuant to Sec. 125.3(c), 
the permit writer must consider the following factors:
    (1) For BPT requirements: (i) The total cost of application of 
technology in relation to the effluent reduction benefits to be achieved 
from such application;
    (ii) The age of equipment and facilities involved;
    (iii) The process employed;
    (iv) The engineering aspects of the application of various types of 
control techniques;
    (v) Process changes; and
    (vi) Non-water quality environmental impact (including energy 
requirements).
    (2) For BCT requirements: (i) The reasonableness of the relationship 
between the costs of attaining a reduction in effluent and the effluent 
reduction benefits derived;
    (ii) The comparison of the cost and level of reduction of such 
pollutants from the discharge from publicly owned treatment works to the 
cost and level of reduction of such pollutants from a class or category 
of industrial sources;
    (iii) The age of equipment and facilities involved;
    (iv) The process employed;
    (v) The engineering aspects of the application of various types of 
control techniques;
    (vi) Process changes; and
    (vii) Non-water quality environmental impact (including energy 
requirements).
    (3) For BAT requirements: (i) The age of equipment and facilities 
involved;
    (ii) The process employed;
    (iii) The engineering aspects of the application of various types of 
control techniques;
    (iv) Process changes;
    (v) The cost of achieving such effluent reduction; and
    (vi) Non-water quality environmental impact (including energy 
requirements).
    (e) Technology-based treatment requirements are applied prior to or 
at the point of discharge.
    (f) Technology-based treatment requirements cannot be satisfied 
through the use of ``non-treatment'' techniques such as flow 
augmentation and in-stream mechanical aerators. However, these 
techniques may be considered as

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a method of achieving water quality standards on a case-by-case basis 
when:
    (1) The technology-based treatment requirements applicable to the 
discharge are not sufficient to achieve the standards;
    (2) The discharger agrees to waive any opportunity to request a 
variance under section 301 (c), (g) or (h) of the Act; and
    (3) The discharger demonstrates that such a technique is the 
preferred environmental and economic method to achieve the standards 
after consideration of alternatives such as advanced waste treatment, 
recycle and reuse, land disposal, changes in operating methods, and 
other available methods.
    (g) Technology-based effluent limitations shall be established under 
this subpart for solids, sludges, filter backwash, and other pollutants 
removed in the course of treatment or control of wastewaters in the same 
manner as for other pollutants.
    (h)(1) The Director may set a permit limit for a conventional 
pollutant at a level more stringent than the best conventional pollution 
control technology (BCT), or a limit for a nonconventional pollutant 
which shall not be subject to modification under section 301 (c) or (g) 
of the Act where:
    (i) Effluent limitations guidelines specify the pollutant as an 
indicator for a toxic pollutant, or
    (ii)(A) The limitation reflects BAT-level control of discharges of 
one or more toxic pollutants which are present in the waste stream, and 
a specific BAT limitation upon the toxic pollutant(s) is not feasible 
for economic or technical reasons;
    (B) The permit identifies which toxic pollutants are intended to be 
controlled by use of the limitation; and
    (C) The fact sheet required by Sec. 124.56 sets forth the basis for 
the limitation, including a finding that compliance with the limitation 
will result in BAT-level control of the toxic pollutant discharges 
identified in paragraph (h)(1)(ii)(B) of this section, and a finding 
that it would be economically or technically infeasible to directly 
limit the toxic pollutant(s).
    (2) The Director may set a permit limit for a conventional pollutant 
at a level more stringent than BCT when:
    (i) Effluent limitations guidelines specify the pollutant as an 
indicator for a hazardous substance, or
    (ii)(A) The limitation reflects BAT-level control of discharges (or 
an appropriate level determined under section 301(c) or (g) of the Act) 
of one or more hazardous substance(s) which are present in the waste 
stream, and a specific BAT (or other appropriate) limitation upon the 
hazardous substance(s) is not feasible for economic or technical 
reasons;
    (B) The permit identifies which hazardous substances are intended to 
be controlled by use of the limitation; and
    (C) The fact sheet required by Sec. 124.56 sets forth the basis for 
the limitation, including a finding that compliance with the limitations 
will result in BAT-level (or other appropriate level) control of the 
hazardous substances discharges identified in paragraph (h)(2)(ii)(B) of 
this section, and a finding that it would be economically or technically 
infeasible to directly limit the hazardous substance(s).
    (iii) Hazardous substances which are also toxic pollutants are 
subject to paragraph (h)(1) of this section.
    (3) The Director may not set a more stringent limit under the 
preceding paragraphs if the method of treatment required to comply with 
the limit differs from that which would be required if the toxic 
pollutant(s) or hazardous substance(s) controlled by the limit were 
limited directly.
    (4) Toxic pollutants identified under paragraph (h)(1) of this 
section remain subject to the requirements of Sec. 122.42(a)(1) 
(notification of increased discharges of toxic pollutants above levels 
reported in the application form).

(Clean Water Act, Safe Drinking Water Act, Clean Air Act, Resource 
Conservation and Recovery Act: 42 U.S.C. 6905, 6912, 6925, 6927, 6974)

[44 FR 32948, June 7, 1979, as amended at 45 FR 33512, May 19, 1980; 48 
FR 14293, Apr. 1, 1983; 49 FR 38052, Sept. 26, 1984; 50 FR 6941, Feb. 
19, 1985; 54 FR 257, Jan. 4, 1989]

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