[Code of Federal Regulations]
[Title 40, Volume 26]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR403.5]

[Page 13-14]
 
                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. 403.5  National pretreatment standards: Prohibited discharges.

    (a)(1) General prohibitions. A User may not introduce into a POTW 
any pollutant(s) which cause Pass Through or Interference. These general 
prohibitions and the specific prohibitions in paragraph (b) of this 
section apply to each User introducing pollutants into a POTW whether or 
not the User is subject to other National Pretreatment Standards or any 
national, State, or local Pretreatment Requirements.
    (2) Affirmative Defenses. A User shall have an affirmative defense 
in any action brought against it alleging a violation of the general 
prohibitions established in paragraph (a)(1) of this section and the 
specific prohibitions in paragraphs (b)(3), (b)(4), (b)(5), (b)(6), and 
(b)(7) of this section where the User can demonstrate that:
    (i) It did not know or have reason to know that its Discharge, alone 
or in conjunction with a discharge or discharges from other sources, 
would cause Pass Through or Interference; and
    (ii)(A) A local limit designed to prevent Pass Through and/or 
Interference, as the case may be, was developed in accordance with 
paragraph (c) of this section for each pollutant in the User's Discharge 
that caused Pass Through or Interference, and the User was in compliance 
with each such local limit directly prior to and during the Pass Through 
or Interference; or
    (B) If a local limit designed to prevent Pass Through and/or 
Interference, as the case may be, has not been developed in accordance 
with paragraph (c) of this section for the pollutant(s) that caused the 
Pass Through or Interference, the User's Discharge directly prior to and 
during the Pass Through or Interference did not change substantially in 
nature or constituents from the User's prior discharge activity when the 
POTW was regularly in compliance with the POTW's NPDES permit 
requirements and, in the case of Interference, applicable requirements 
for sewage sludge use or disposal.
    (b) Specific prohibitions. In addition, the following pollutants 
shall not be introduced into a POTW:
    (1) Pollutants which create a fire or explosion hazard in the POTW, 
including, but not limited to, wastestreams with a closed cup flashpoint 
of less than 140 degrees Farenheit or 60 degrees Centigrade using the 
test methods specified in 40 CFR 261.21.
    (2) Pollutants which will cause corrosive structural damage to the 
POTW, but in no case Discharges with pH

[[Page 14]]

lower than 5.0, unless the works is specifically designed to accommodate 
such Discharges;
    (3) Solid or viscous pollutants in amounts which will cause 
obstruction to the flow in the POTW resulting in Interference;
    (4) Any pollutant, including oxygen demanding pollutants (BOD, etc.) 
released in a Discharge at a flow rate and/or pollutant concentration 
which will cause Interference with the POTW.
    (5) Heat in amounts which will inhibit biological activity in the 
POTW resulting in Interference, but in no case heat in such quantities 
that the temperature at the POTW Treatment Plant exceeds 40 
[deg]C (104 [deg]F) unless the Approval Authority, 
upon request of the POTW, approves alternate temperature limits.
    (6) Petroleum oil, nonbiodegradable cutting oil, or products of 
mineral oil origin in amounts that will cause interference or pass 
through;
    (7) Pollutants which result in the presence of toxic gases, vapors, 
or fumes within the POTW in a quantity that may cause acute worker 
health and safety problems;
    (8) Any trucked or hauled pollutants, except at discharge points 
designated by the POTW.
    (c) When specific limits must be developed by POTW. (1) Each POTW 
developing a POTW Pretreatment Program pursuant to Sec. 403.8 
shall develop and enforce specific limits to implement the prohibitions 
listed in paragraphs (a)(1) and (b) of this section. Each POTW with an 
approved pretreatment program shall continue to develop these limits as 
necessary and effectively enforce such limits.
    (2) All other POTW's shall, in cases where pollutants contributed by 
User(s) result in Interference or Pass-Through, and such violation is 
likely to recur, develop and enforce specific effluent limits for 
Industrial User(s), and all other users, as appropriate, which, together 
with appropriate changes in the POTW Treatment Plant's facilities or 
operation, are necessary to ensure renewed and continued compliance with 
the POTW's NPDES permit or sludge use or disposal practices.
    (3) Specific effluent limits shall not be developed and enforced 
without individual notice to persons or groups who have requested such 
notice and an opportunity to respond.
    (d) Local limits. Where specific prohibitions or limits on 
pollutants or pollutant parameters are developed by a POTW in accordance 
with paragraph (c) above, such limits shall be deemed Pretreatment 
Standards for the purposes of section 307(d) of the Act.
    (e) EPA enforcement actions under section 309(f) of the Clean Water 
Act.
    If, within 30 days after notice of an Interference or Pass Through 
violation has been sent by EPA to the POTW, and to persons or groups who 
have requested such notice, the POTW fails to commence appropriate 
enforcement action to correct the violation, EPA may take appropriate 
enforcement action under the authority provided in section 309(f) of the 
Clean Water Act.

[46 FR 9439, Jan. 28, 1981, as amended at 51 FR 20430, June 4, 1986; 52 
FR 1600, Jan. 14, 1987; 55 FR 30129, July 24, 1990; 60 FR 33932, June 
29, 1995]