Disclaimer

Mention of trade names or commercial products in this

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Introduction to the National Pretreatment Program Table of Contents

-iTABLE OF CONTENTS

Page

Preface ................................................................. iii 

List of Acronyms .......................................................... v 

Glossary of Terms ....................................................... vii 

1. POTWs and the Need for the Pretreatment Program ............................. 1 

Sewage Treatment ................................................... 1 

Need for the Pretreatment Program ...................................... 2 

2. Overview of the National Pretreatment Program ................................ 5 

The Clean Water Act ................................................. 5 

The General Pretreatment Regulations .................................... 6 

POTW Pretreatment Programs ......................................... 7 

3. Pretreatment Standards ................................................... 11 

Prohibited Discharge Standards ........................................ 11 

Categorical Standards ............................................... 12 

Local Limits ....................................................... 20 

Summary of Standards ............................................... 22 

4. POTW Pretreatment Program Responsibilities ................................. 23 

Legal Authority ..................................................... 23 

Industrial Waste Surveys ............................................. 24 

Permitting ......................................................... 25 

Inspections ........................................................ 26 

Sampling ......................................................... 27 

Enforcement ....................................................... 28 

Data Management and Record Keeping .................................. 31 

Public Participation and POTW Reporting ................................ 32 

5. Industrial User Pretreatment Program Responsibilities .......................... 35 

Reporting Requirements .............................................. 35 

Self-Monitoring Requirements ......................................... 39 

Record Keeping Requirements ......................................... 40 

6. Hauled Wastes .......................................................... 43 

Nature of Hauled Wastes ............................................. 43 

Control Programs ................................................... 43 

Concerns ......................................................... 45 

7. Pollution Prevention ...................................................... 47 

Pollution Prevention and the Pretreatment Program ......................... 48 

Benefits of Pollution Prevention ........................................ 49 

Pollution Prevention Assistance ........................................ 50 

8. Bibliography ............................................................ 51 

APPENDICES

A Annotated Summaries of Existing Pretreatment Guidance Material ............... A-1 

B Document Ordering Information ........................................... B-1 

C EPA/State Primary Pretreatment Contacts/Addresses .......................... C-1 
Introduction to the National Pretreatment Program Preface

1 EPA, Environmental Regulations and Technology: The National Pretreatment Program, July 1986,

p.4.

-iiiPREFACE

The industrial boom in the United States during the 1950s and 60s brought with it a level of pollution

never before seen in this country. Scenes of dying fish, burning rivers, and thick black smog engulfing major

metropolitan areas were images and stories repeated regularly on the evening news. In December of 1970,

the President of the United States created the U.S. Environmental Protection Agency (EPA) through an

executive order in response to these critical environmental problems.

In 1972, Congress passed the Clean Water Act (CWA) to restore and maintain the integrity of the

nation’s waters. Although prior legislation had been enacted to address water pollution, those previous

efforts were developed with other goals in mind. For example, the 1899 Rivers and Harbors Act protected

navigational interests while the 1948 Water Pollution Control Act and the 1956 Federal Water Pollution

Control Act merely provided limited funding for State and local governments to address water pollution

concerns on their own. 

The CWA required the elimination of the discharge of pollutants into the nation’s waters and the

achievement of fishable and swimmable water quality levels. EPA’s National Pollutant Discharge Elimination

System (NPDES) Permitting Program represents one of the key components established to accomplish this

feat. The NPDES program requires that all point source discharges to waters of the U.S. (i.e., “direct

discharges”) must be permitted.

To address “indirect discharges” from industries to Publicly Owned Treatment Works (POTWs), EPA,

through CWA authorities, established the National Pretreatment Program as a component of the NPDES

Permitting Program. The National Pretreatment Program requires industrial and commercial dischargers

to treat or control pollutants in their wastewater prior to discharge to POTWs. 

In 1986, more than one-third of all toxic pollutants entered the nation’s waters from publicly owned

treatment works (POTWs) through industrial discharges to public sewers.1 Certain industrial discharges,

such as slug loads, can interfere with the operation of POTWs, leading to the discharge of untreated or

inadequately treated wastewater into rivers, lakes, etc. Some pollutants are not compatible with biological

wastewater treatment at POTWs and may pass through the treatment plant untreated. This “pass through”

of pollutants impacts the surrounding environment, occasionally causing fish kills or other detrimental

alterations of the receiving waters. Even when POTWs have the capability to remove toxic pollutants from

wastewater, these toxics can end up in the POTW’s sewage sludge, which in many places is land applied

to food crops, parks, or golf courses as fertilizer or soil conditioner. 

The National Pretreatment Program is unique in that the General Pretreatment Regulations require all

large POTWs (i.e., those designed to treat flows of more than 5 million gallons per day) and smaller POTWs

with significant industrial discharges to establish local pretreatment programs. These local programs must

enforce all national pretreatment standards and requirements in addition to any more stringent local

requirements necessary to protect site-specific conditions at the POTW. More than 1,500 POTWs have

developed and are implementing local pretreatment programs designed to control discharges from

approximately 30,000 significant industrial users. 

Since 1983, the Pretreatment Program has made great strides in reducing the discharge of toxic

pollutants to sewer systems and to waters of the U.S. In the eyes of many, the Pretreatment Program,

implemented as a partnership between EPA, States, and POTWs, is a notable success story in reducing

impacts to human health and the environment. These strides can be attributed to the efforts of many

Federal, State, local, and industrial representatives who have been involved with developing and

implementing the various aspects of the Pretreatment Program. 
Preface Introduction to the National Pretreatment Program

-ivEPA has supported the Pretreatment Program through development of numerous guidance manuals.

EPA has released more than 30 manuals that provide guidance to EPA, States, POTWs, and industry on

various pretreatment program requirements and policy determinations. Through this guidance, the

Pretreatment Program has maintained national consistency in interpretation of the regulations. 

Nevertheless, turnover in pretreatment program staff has diluted historical knowledge leaving new staff

and other interested parties unaware of existing materials. With this in mind, the intent of this guidance

manual, Introduction to the National Pretreatment Program, is to:

(1) provide a reference for anyone interested in understanding the basics of pretreatment program

requirements, and 

(2) provide a roadmap to additional and more detailed guidance materials for those trying to

implement specific elements of the Pretreatment Program. 

While the Pretreatment Program has demonstrated significant reductions in pollutants discharged to

POTWs, Congress’ goals of zero discharge of toxic pollutants and fishable/swimmable water quality have

not been realized. EPA is currently working to establish more cost-effective and common sense approaches

to environmental protection (e.g., using watershed, streamlining, and reinvention concepts), creating new

responsibilities for all those involved in the National Pretreatment Program. Many current challenges

remain, while many new ones likely lie ahead. This guidance manual is intended to provide an

understanding of the basic concepts that drive the Program, the current status of the Program and program

guidance, and an insight into what the future holds for all those involved with implementing the Pretreatment

Program.

As noted above, this guidance manual is organized to provide an overview of program requirements and

to refer the reader to more detailed EPA guidance that exists on specific program elements. To accomplish

this, the guidance manual incorporates two key features: 1) the first page of each chapter contains a list of

EPA references applicable to the topics discussed in that chapter, and 2) abstracts of each reference are

provided in Appendix A with document ordering information provided in Appendix B. Addresses of EPA and

State pretreatment staff are provided in Appendix C. Additionally, Chapter 8 contains a bibliography of these

guidance materials, and other materials that may be useful to the reader and describes how to obtain them.
Introduction to the National Pretreatment Program List of Acronyms

-vLIST OF ACRONYMS

Acronym Full Phrase

AA Approval Authority

AO Administrative Order

BAT Best Available Technology Economically Achievable

BCT Best Conventional Pollutant Control Technology

BMP Best Management Practices

BMR Baseline Monitoring Report

BOD5 5-day Biochemical Oxygen Demand

BPJ Best Professional Judgment

BPT Best Practicable Control Technology Currently Available

CA Control Authority

CFR Code of Federal Regulations

CIU Categorical Industrial User

CSO Combined Sewer Overflow

CWA Clean Water Act (formerly referred to as the Federal Water Pollution Control Act or Federal

Water Pollution Control Act Amendments of 1972) Pub. L. 92-500, as amended by Pub. L. 95-

217, Pub. L. 95-576, Pub. L. 96-483, Pub. L. 97-117, and Pub. L. 100-4, 33 U.S.C. 1251 et seq.

CWF Combined Wastestream Formula

CWT Centralized Waste Treater

DMR Discharge Monitoring Report

DSE Domestic Sewage Exclusion

DSS Domestic Sewage Study

ELG Effluent Limitations Guideline

EPA Environmental Protection Agency

EPCRA Emergency Preparedness and Community Right to Know Act

ERP Enforcement Response Plan

FDF Fundamentally Different Factors

FR Federal Register

FWA Flow Weighted Average

gpd Gallons per Day

IU Industrial User

LEL Lower Explosive Limit

MAHL Maximum Allowable Headworks Loading

MAIL Maximum Allowable Industrial Loading

MGD Million Gallons per Day

MSDS Material Safety Data Sheet

NAICS North American Industry Classification System (replaces SIC coding system in 1998)

NOV Notice of Violation

NPDES National Pollutant Discharge Elimination System

NRDC Natural Resources Defense Council

NSPS New Source Performance Standard

O&G Oil and Grease

Acronym Full Phrase
List of Acronyms Introduction to the National Pretreatment Program

-viO&M Operations and Maintenance

OCPSF Organic Chemicals, Plastics, and Synthetic Fibers

P2 Pollution Prevention

PCI Pretreatment Compliance Inspection

PCS Permit Compliance System

PIRT Pretreatment Implementation Review Task Force

POTW Publicly Owned Treatment Works

PSES Pretreatment Standards for Existing Sources

PSNS Pretreatment Standards for New Sources

QA/QC Quality Assurance/Quality Control

RCRA Resource Conservation and Recovery Act

SIC Standard Industrial Classification

SIU Significant Industrial User

SPCC Spill Prevention Control and Countermeasures

SNC Significant Noncompliance

SSO Sanitary Sewer Overflow

SUO Sewer Use Ordinance

TCLP Toxicity Characteristic Leaching Procedure

TIE Toxicity Identification Evaluation

TOMP Toxic Organic Management Program

TRE Toxicity Reduction Evaluation

TRI Toxic Release Inventory

TSS Total Suspended Solids

TTO Total Toxic Organics

USC United States Code

UST Underground Storage Tank

WET Whole Effluent Toxicity

WWTP Wastewater Treatment Plant
Introduction to the National Pretreatment Program Glossary of Terms

-viiGLOSSARY OF TERMS

This glossary includes a collection of terms used in this manual and an explanation of each term. To

the extent that definitions and explanations provided in this glossary differ from those in EPA regulations or

other official documents, the definitions used herein are intended for use in understanding this manual only.

Act or “the Act” [40 CFR §403.3(b)]

The Federal Water Pollution Control Act, also known as the Clean Water Act, as amended, 33 USC 1251

et.seq.

Approval Authority [40 CFR §403.3(c)]

The Director in an NPDES State with an approved State Pretreatment Program and the appropriate EPA

Regional Administrator in a non-NPDES State or State without an approved pretreatment program.

Approved POTW Pretreatment Program or Program [40 CFR §403.3(d)]

A program administered by a POTW that meets the criteria established in 40 CFR Part 403 and which

has been approved by a Regional Administrator or State Director.

Approved State Pretreatment Program

A program administered by a State that meets the criteria established in 40 CFR §403.10 and which has

been approved by a Regional Administrator

Approved/Authorized State

A State with an NPDES permit program approved pursuant to section 402(b) of the Act and an approved

State Pretreatment Program.

Baseline Monitoring Report (BMR) [paraphrased from 40 CFR §403.12(b)]

A report submitted by categorical industrial users (CIUs) within 180 days after the effective date of an

applicable categorical standard, or at least 90 days prior to commencement of discharge for new sources,

which contains specific facility information, including flow and pollutant concentration data. For existing

sources, the report must also certify as to the compliance status of the facility with respect to the categorical

standards.

Best Available Technology Economically Achievable (BAT)

A level of technology based on the best existing control and treatment measures that are economically

achievable within the given industrial category or subcategory.

Best Management Practices (BMPs)

Schedules of activities, prohibitions of practices, maintenance procedures, and other management

practices to prevent or reduce the pollution of waters of the U.S. BMPs also include treatment requirements,

operating procedures and practices to control plant site runoff, spillage or leaks, sludge or waste disposal,

or drainage from raw material storage.

Best Practicable Control Technology Currently Available (BPT)

A level of technology represented by the average of the best existing wastewater treatment performance

levels within an industrial category or subcategory.

Best Professional Judgment (BPJ)

The method used by a permit writer to develop technology-based limitations on a case-by-case basis

using all reasonably available and relevant data.

Blowdown
Glossary of Terms Introduction to the National Pretreatment Program

-viiiThe discharge of water with high concentrations of accumulated solids from boilers to prevent plugging

of the boiler tubes and/or steam lines. In cooling towers, blowdown is discharged to reduce the concentration

of dissolved salts in the recirculating cooling water.

Bypass [40 CFR §403.17(a)]

The intentional diversion of wastestreams from any portion of an Industrial User’s treatment facility.

Categorical Industrial User (CIU)

An industrial user subject to National categorical pretreatment standards.

Categorical Pretreatment Standards

Limitations on pollutant discharges to POTWs promulgated by EPA in accordance with Section 307 of

the Clean Water Act, that apply to specific process wastewater discharges of particular industrial categories

[40 CFR § 403.6 and 40 CFR Parts 405-471].

Chain of Custody (COC)

A record of each person involved in the possession of a sample from the person who collects the sample

to the person who analyzes the sample in the laboratory.

Chronic

A stimulus that lingers or continues for a relatively long period of time, often one-tenth of the life span

or more. Chronic should be considered a relative term depending on the life span of an organism. The

measurement of chronic effect can be reduced growth, reduced reproduction, etc., in addition to lethality.

Clean Water Act (CWA)

The common name for the Federal Water Pollution Control Act. Public law 92-500; 33 U.S.C. 1251 et

seq.; legislation which provides statutory authority for both NPDES and Pretreatment Programs. 

Code of Federal Regulations (CFR)

A codification of Federal rules published annually by the Office of the Federal Register National Archives

and Records Administration. Title 40 of the CFR contains the regulations for Protection of the Environment.

Combined Sewer Overflow (CSO)

A discharge of untreated wastewater from a combined sewer system at a point prior to the headworks

of a publicly owned treatment works. CSOs generally occur during wet weather (rainfall or snowfall). During

periods of wet weather, these systems become overloaded, bypass treatment works, and discharge directly

to receiving waters.

Combined Wastestream Formula (CWF) [paraphrased from 40 CFR §403.6(e)]

Procedure for calculating alternative discharge limits at industrial facilities where a regulated

wastestream from a categorical industrial user is combined with other wastestreams prior to treatment.

Compliance Schedule

A schedule of remedial measures included in a permit or an enforcement order, including a sequence

of interim requirements (for example, actions, operations, or milestone events) that lead to compliance with

the CWA and regulations.

Composite Sample

Sample composed of two or more discrete samples. The aggregate sample will reflect the average

water quality covering the compositing or sample period.

Concentration-based Limit

A limit based upon the relative strength of a pollutant in a wastestream, usually expressed in mg/l.

Continuous Discharge
Introduction to the National Pretreatment Program Glossary of Terms

-ixA discharge that occurs without interruption during the operating hours of a facility, except for infrequent

shutdowns for maintenance, process changes or similar activities.

Control Authority [paraphrased from 40 CFR § 403.12(a)]

A POTW with an approved pretreatment program or the approval authority in the absence of a POTW

pretreatment program.

Conventional Pollutants

BOD, TSS, fecal coliform, oil and grease, and pH

Daily Maximum Limitations

The maximum allowable discharge of pollutants during a 24 hour period. Where daily maximum

limitations are expressed in units of mass, the daily discharge is the total mass discharged over the course

of the day. Where daily maximum limitations are expressed in terms of a concentration, the daily discharge

is the arithmetic average measurement of the pollutant concentration derived from all measurements taken

that day.

Detection Limit

The minimum concentration of an analyte(substance) that can be measured and reported with a 99%

confidence that the analyte concentration is greater than zero as determined by the procedure set forth in

40 CFR Part 136, Appendix B.

Development Document

Detailed report of studies conducted by the U.S. EPA for the purpose of establishing effluent guidelines

and categorical pretreatment standards.

Dilute Wastestream [paraphrased from 40 CFR §403.6(e)(1)(i)]

For purposes of the combined wastestream formula, the average daily flow (at least a 30-day average)

from : (a) boiler blowdown streams, non-contact cooling streams, storm water streams, and demineralized

backwash streams; provided, however, that where such streams contain a significant amount of a pollutant,

and the combination of such streams, prior to treatment, with an industrial user's regulated process

wastestream(s) will result in a substantial reduction of that pollutant, the Control Authority, upon application

of the industrial user, may exercise its discretion to determine whether such stream(s) should be classified

as diluted or unregulated. In its application to the Control Authority, the industrial user must provide

engineering, production, sampling and analysis, and such other information so the control authority can make

its determination; or (b) sanitary wastestreams where such streams are not regulated by a categorical

pretreatment standard; or (c) from any process wastestreams which were, or could have been, entirely

exempted from categorical pretreatment standards pursuant to paragraph 8 of the NRDC v. Costle Consent

Decree (12 ERC 1833) for one more of the following reasons (see Appendix D of 40 CFR Part 403):

a. the pollutants of concern are not detectable in the effluent from the industrial user (paragraph

(8)(a)(iii));

b. the pollutants of concern are present only in trace amounts and are neither causing nor likely to

cause toxic effects (paragraph (8)(a)(iii));

c. the pollutants of concern are present in amounts too small to be effectively deduced by technologies

known to the Administrator (paragraph (8)(a)(iii)); or

d. the wastestream contains only pollutants which are compatible with the POTW (paragraph (8)(b)(I)).

Effluent Limitations Guideline

Any effluent limitations guidelines issued by EPA pursuant to Section 304(b) of the CWA. These

regulations are published to adopt or revise a national standard prescribing restrictions on quantities, rates,

and concentrations of chemical, physical, biological, and other constituents which are discharged from point

sources, in specific industrial categories (e.g., metal finishing, metal molding and casting, etc).

Enforcement Response Plan [paraphrased from 40 CFR §403.8(f)(5)]

Step-by-step enforcement procedures followed by Control Authority staff to identify, document, and

respond to violations.
Glossary of Terms Introduction to the National Pretreatment Program

-xExisting Source

Any source of discharge, the construction or operation of which commenced prior to the publication by

the EPA of proposed categorical pretreatment standards, which will be applicable to such source if the

standard is thereafter promulgated in accordance with Section 307 of the Act.

Federal Water Pollution Control Act (FWPCA)

The title of Public law 92-500; 33 U.S.C. 1251 et seq., also known as the Clean Water Act (CWA),

enacted October 18, 1972.

Flow Weighted Average Formula (FWA) [paraphrased from 40 CFR §403.6(e)]

A procedure used to calculate alternative limits where wastestreams regulated by a categorical

pretreatment standard and nonregulated wastestreams combine after treatment but prior to the monitoring

point.

Flow Proportional Composite Sample

Combination of individual samples proportional to the flow of the wastestream at the time of sampling.

Fundamentally Different Factors [paraphrased from 40 CFR §403.13]

Case-by-case variance from categorical pretreatment standards based on the factors considered by EPA

in developing the applicable category/subcategory being fundamentally different than factors relating to a

specific industrial user.

General Prohibitions [40 CFR §403.5(a)(1)]

No user shall introduce into a POTW any pollutant(s) which cause pass through or interference.

Grab Sample

A sample which is taken from a wastestream on a one-time basis with no regard to the flow of the

wastestream and without consideration of time. A single grab sample should be taken over a period of time

not to exceed 15 minutes.

Indirect Discharge or Discharge [40 CFR §403.3(g)]

The introduction of pollutants into a POTW from any non-domestic source regulated under section

307(b), (c), or (d) of the Act.

Industrial User (IU) or User [40 CFR §403.3(h)]

A source of indirect discharge.

Industrial Waste Survey

The process of identifying and locating industrial users and characterizing their industrial discharge.

Inhibition Concentration

Estimate of the toxicant concentration that would cause a given percent reduction (e.g., IC25) in a

nonlethal biological measurement of the test organisms, such as reproduction or growth.

Interference [paraphrased from 40 CFR §403.3(i)]

A discharge which, alone or in conjunction with a discharge or discharges from other sources, both: (1)

inhibits or disrupts the POTW, its treatment processes or operations, or its sludge processes, use or disposal;

and (2) therefore is a cause of a violation of any requirement of the POTW's NPDES permit (including an

increase in the magnitude or duration of a violation) or of the prevention of sewage sludge use or disposal

in compliance with ... [applicable] statutory provisions and regulations or permits issued thereunder (or more

stringent State or local regulations) ...

Local Limits [paraphrased 40 CFR § 403.5(c)]

Specific discharge limits developed and enforced by POTWs upon industrial or commercial facilities to

implement the general and specific discharge prohibitions listed in 40 CFR §§403.5(a)(1) and (b).
Introduction to the National Pretreatment Program Glossary of Terms

-xiMonthly Average

The arithmetic average value of all samples taken in a calendar month for an individual pollutant

parameter. The monthly average may be the average of all grab samples taken in a given calendar month,

or the average of all composite samples taken in a given calendar month.

National Pollutant Discharge Elimination System (NPDES)

The national program for issuing, modifying, revoking and reissuing, terminating, monitoring and

enforcing discharge permits from point sources to waters of the United States, and imposing and enforcing

pretreatment requirements, under sections 307, 402, 318, and 405 of the CWA.

National Pretreatment Standard or Pretreatment Standard or Standard [40 CFR §403.3(j)]

Any regulation containing pollutant discharge limits promulgated by the EPA in accordance with section

307(b) and (c) of the Act, which applies to Industrial Users. This term includes prohibitive discharge limits

established pursuant to §403.5.

New Source [40 CFR §403.3(k)]

Any building, structure, facility or installation from which there is or may be a discharge of pollutants, the

construction of which commenced after the publication of proposed Pretreatment Standards under section

307(c) of the Act which will be applicable to such source if such standards are thereafter promulgated in

accordance with that section provided that:

(a) The building, structure, facility or installation is constructed at a site at which no other discharge

source is located; or

(b) The building, structure, facility or installation totally replaces the process or production equipment

that causes the discharge of pollutants at an existing source; or 

(c) The production or wastewater generating processes of the building, structure, facility, or installation

are substantially independent of an existing source at the same site. In determining whether these

are substantially independent, factors such as the extent to which the new facility is integrated with

the existing plant, and the extent to which the new facility is engaged in the same general type of

activity as the existing source, should be considered.

Construction on a site at which an existing source is located results in a modification rather than a new

source if the construction does not create a new building, structure, facility, or installation meeting the criteria

of paragraphs (k)(1)(ii), or (k)(1)(iii) of this section but otherwise alters, replaces, or adds to existing process

or production equipment.

Construction of a new source, as defined under this paragraph has commenced if the owner or operator has:

(i) Begun, or caused to begin as part of a continuous onsite construction program:

(A) Any placement, assembly, or installation of facilities or equipment; or

(B) Significant site preparation work including clearing, excavation, or removal of existing buildings,

structures, or facilities which is necessary for the placement, assembly, or installation of new

source facilities or equipment, or

(C) Entered into a binding contractual obligation for the purchase of facilities or equipment which

are intended to be used in its operation within a reasonable time. Options to purchase or

contracts which can be terminated or modified without substantial loss, and contracts for

feasibility, engineering, and design studies do not constitute a contractual obligation under this

paragraph.

90-Day Final Compliance Report [40 CFR §403.12(d)]

A report submitted by categorical industrial users within 90 days following the date for final compliance

with the standards. This report must contain flow measurement (of regulated process streams and other
Glossary of Terms Introduction to the National Pretreatment Program

-xiistreams), measurement of pollutants, and a certification as to whether the categorical standards are being

met.

Nonconventional Pollutants

Any pollutant that is neither a toxic pollutant nor a conventional pollutant (e.g., manganese, ammonia,

etc.)

Non-Contact Cooling Water

Water used for cooling which does not come into direct contact with any raw material, intermediate

product, waste product, or finished product. The only pollutant contributed from the discharge is heat.

Non-Regulated Wastestream

Unregulated and dilute wastestreams (not regulated by categorical standards).

Pass Through [40 CFR §403.3(n)]

A discharge which exits the POTW into waters of the United States in quantities or concentrations which,

alone or in conjunction with a discharge or discharges from other sources, is a cause of a violation of any

requirement of the POTW's NPDES permit (including an increase in the magnitude or duration of a

violation).

Periodic Compliance Report [paraphrased from 40 CFR §403.12(e) & (h)]

A report on compliance status submitted by categorical industrial users and significant noncategorical

industrial users to the control authority at least semiannually (once every six months).

Point Source [40 CFR 122.2]

Any discernible, confined, and discrete conveyance, including but not limited to any pipe, ditch, channel,

tunnel, conduit, well, discrete fixture, container, rolling stock concentrated animal feeding operation vessel,

or other floating craft from which pollutants are or may be discharged.

Pollutant [40 CFR 122.2]

Dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge,

munitions, chemical wastes, biological materials, radioactive materials (except those regulated under the

Atomic Energy Act of 1954, as amended (42 U.S.C. 2011 et seq.)), heat, wrecked or discarded equipment,

rock, sand, cellar dirt, and industrial, municipal and agricultural waste discharged into water.

Pretreatment [paraphrased from 40 CFR §403.3(q)]

The reduction of the amount of pollutants, the elimination of pollutants, or the alteration of the nature

of pollutant properties in wastewater prior to or in lieu of discharging or otherwise introducing such pollutants

into a POTW.

Pretreatment Requirements [40 CFR §403.3(r)]

Any substantive or procedural requirement related to Pretreatment, other than a National Pretreatment

Standard, imposed on an Industrial User.

Pretreatment Standards for Existing Sources (PSES)

Categorical Standards and requirements applicable to industrial sources that began construction prior

to the publication of the proposed pretreatment standards for that industrial category.(see individual

standards at 40 CFR Parts 405-471.)

Pretreatment Standards for New Sources (PSNS)

Categorical Standards and requirements applicable to industrial sources that began construction after

the publication of the proposed pretreatment standards for that industrial category. (see individual standards

at 40 CFR Parts 405-471.)

Priority Pollutant
Introduction to the National Pretreatment Program Glossary of Terms

-xiiiPollutant listed by the Administrator of EPA under Clean Water Act section 307(a). The list of the current

126 Priority Pollutants can be found in 40 CFR Part 423 Appendix A.

Process Wastewater

Any water which, during manufacturing or processing, comes into contact with or results from the

production or use of any raw material, intermediate product, finished product, byproduct, or waste product.

Production-Based Standards

A discharge standard expressed in terms of pollutant mass allowed in a discharge per unit of product

manufactured.

Publicly Owned Treatment Works (POTW) [40 CFR §403.3(o)]

A treatment works as defined by section 212 of the Act, which is owned by a State or municipality (as

defined by section 502(4) of the Act). This definition includes any devices or systems used in the storage,

treatment, recycling, and reclamation of municipal sewage or industrial wastes of a liquid nature. It also

includes sewers, pipes or other conveyances only if they convey wastewater to a POTW Treatment Plant.

The term also means the municipality as defined in section 502(4) of the Act, which has jurisdiction over the

Indirect Discharges to and the discharges from such a treatment works.

Regulated Wastestream

For purposes of applying the combined wastestream formula, a wastestream from an industrial process

that is regulated by a categorical standard.

Removal Credit [paraphrased from 40 CFR §403.7]

Variance from a pollutant limit specified in a categorical pretreatment standard to reflect removal by the

POTW of said pollutant.

Representative Sample

A sample from a wastestream that is as nearly identical as possible in composition to that in the larger

volume of wastewater being discharged and typical of the discharge from the facility on a normal operating

day.

Sanitary Sewer Overflow (SSO)

Untreated or partially treated sewage overflows from a sanitary sewer collection system.

Self-Monitoring

Sampling and analyses performed by a facility to ensure compliance with a permit or other regulatory

requirements.

Sewer Use Ordinance (SUO)

A legal mechanism implemented by a local government entity which sets out, among others,

requirements for the discharge of pollutants into a publicly owned treatment works.

Significant Industrial User (SIU) [paraphrased from 40 CFR §403.3(t)]

(1) All users subject to Categorical Pretreatment Standards under 40 CFR 403.6 and 40 CFR chapter

I, subchapter N; and (2) Any other industrial user that: discharges an average of 25,000 gallons per day or

more of process wastewater to the POTW (excluding sanitary, noncontact cooling and boiler blowdown

wastewater); contributes a process wastestream which makes up 5 percent or more of the average dry

weather hydraulic or organic capacity of the POTW treatment plant; or is designated as such by the Control

Authority as defined in 40 CFR 403.12(a) on the basis that the industrial user has a reasonable potential for

adversely affecting the POTW’s operation or for violating any pretreatment standard or requirement (in

accordance with 40 CFR 403.8(f)(6)].

Significant Noncompliance (SNC) [40 CFR §403.8(f)(2)(vii)]

Industrial user violations meeting one or more of the following criteria:

1) Chronic violations of wastewater discharge limits, defined here as those in which sixty-six

percent or more of all of the measurements taken during a six month period exceed (by any

magnitude) the daily maximum limit or the average limit for the same pollutant parameter;
Glossary of Terms Introduction to the National Pretreatment Program

-xiv2) Technical Review Criteria (TRC) violations, defined here as those in which thirty-three percent

or more of all of the measurements for each pollutants parameter taken during a six-month period

equal or exceed the product of the daily maximum limit or the average limit multiplied by the

applicable TRC (TRC=1.4 for BOD, TSS, fats, oil, and grease, and 1.2 for all other pollutants except

pH);

3) Any other violation of a pretreatment effluent limit (daily maximum or longer-term average) that

the Control Authority determines has caused, alone or in combination with other dischargers,

interference or pass through (including endangering the health of POTW personnel or the general

public);

4) Any discharge of a pollutant that has caused imminent endangerment to human health, welfare

or to the environment or has resulted in the POTW’s exercise of its emergency authority under

paragraph (f)(1)(vi)(B) of this section to halt or prevent such a discharge;

5) Failure to meet, within 90 days after the schedule date, a compliance schedule milestone

contained in a local control mechanism or enforcement order for starting construction, completing

construction, or attaining final compliance;

6) Failure to provide, within 30 days after the due date, required reports such as baseline

monitoring reports, 90-day compliance reports, periodic self-monitoring reports, and reports on

compliance with compliance schedules;

7) Failure to accurately report noncompliance;

8) Any other violation or group of violations which the Control Authority determines will adversely

affect the operation or implementation of the local pretreatment program.

Slug Discharge [40 CFR §403.8(f)(2)(v)]

Any discharge of a non-routine, episodic nature, including but not limited to, an accidental spill or a

noncustomary batch discharge.

Specific Prohibitions [40 CFR §403.5(b)]

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 Fahrenheit or 60 degrees

Centigrade using the test methods specified in 40 CFR Part 261.21;

2) Pollutants which will cause corrosive structural damage to the POTW, but in no case discharges

with pH 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 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°C(104°F) unless the Approval Authority, upon request of the POTW, approves alternative

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.

Standard Industrial Classification (SIC)

A system developed by the U.S. Office of Management and Budget that is used to classify various types

of business entities. Effective in 1998, the SIC scheme is replace by the North American Industry

Classification System (NAICS), although EPA has not yet implemented this change.

Storm Water

Rain water, snow melt, and surface runoff and drainage.

Time Proportional Composite Sample

A sample consisting of a series of aliquots collected from a representative point in the discharge stream

at equal time intervals over the entire discharge period on the sampling day.
Introduction to the National Pretreatment Program Glossary of Terms

-xvToxic Pollutant

Any pollutant listed as toxic under section 307(a)(1) of the CWA, or in the case of sludge use or disposal

practices, any pollutant identified in regulations implementing section 405(d) of the CWA.

Toxicity Reduction Evaluation

A site-specific study conducted in a stepwise process designed to identify the causative agent(s) of

effluent toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then

confirm the reduction in effluent toxicity.

Toxicity Test

A procedure to determine the toxicity of a chemical or an effluent using living organisms. A toxicity test

measures the degree of effect on exposed test organisms of a specific chemical or effluent.

Toxicity Identification Evaluation

Set of procedures to identify the specific chemicals responsible for effluent toxicity.

Unregulated Wastestream

For purposes of applying the combined wastestream formula, a wastestream not regulated by a

categorical standard nor considered a dilute wastestream.

Upset [paraphrased from 40 CFR §403.16(a)]

An exceptional incident in which there is unintentional and temporary noncompliance with categorical

Pretreatment Standards because of factors beyond the reasonable control of the Industrial User. An Upset

does not include noncompliance to the extent caused by operational error, improperly designed treatment

facilities, inadequate treatment facilities, lack of preventative maintenance, or careless or improper

operation.

Water Quality Criteria

Comprised of both numeric and narrative criteria. Numeric criteria are scientifically derived ambient

concentrations developed by EPA or States for various pollutants of concern to protect human health and

aquatic life. Narrative criteria are statements that describe the desired water quality goal.

Water Quality Standard

A statute or regulation that consists of the beneficial designated use or uses of a waterbody, the numeric

and narrative water quality criteria that are necessary to protect the use or uses of that particular waterbody,

and an antidegradation statement.

Whole Effluent Toxicity

The total toxic effect of an effluent measured directly with a toxicity test.
Introduction to the National Pretreatment Program POTWs and the Need for the Pretreatment Program

2 The Nalco Water Handbook, ed. Frank N. Kemmer (New York: McGraw-Hill Book Company,

1988), pp. 35.1.

3

Ibid, p. 36.1.

4

1996 Clean Water Needs Survey Report to Congress: Assessment of Needs for Publicly

Owned Wastewater Treatment Facilities, Correction of Combined Sewer Overflows, and

Management of Stormwater and Nonpoint Source Pollution in the United States.

Chapter 1 -1-

Environmental Regulations and Technology: The National Pretreatment Program

National Pretreatment Program: Report to Congress

Report to Congress on the Discharge of Hazardous Wastes to POTWs

Chapter 1. Applicable EPA References

1. POTWS AND THE NEED FOR THE

PRETREATMENT PROGRAM

The average American uses

roughly 100 to 200 gallons of

water a day, with less than one

percent of that water actually

being consumed.2 The rest is

used for activities such as

washing, preparing food, watering

lawns, heating and cooling,

transporting wastes, and fire protection. The public is very conscious about the quality of water that comes out

of their tap each day, quickly notifying authorities of changes in appearance, odor, and taste. These same

Americans, on average, discharge about the same amount of wastewater to local sewage treatment plants

daily.3 This wastewater (commonly referred to as “domestic sewage”) receives much less attention than drinking

water, likely the result of an “out of sight, out of mind” attitude. 

Most people take it for granted that once down the drain, wastes will be handled appropriately. In fact, this

attitude has carried over to industry as well, as can be seen by reading the labels of many household products.

These labels often recommend that waste or excess product be disposed of down the drain. Other toxic or

hazardous products are actually designed to be disposed of down the drain (e.g., drain clog remover). Recall

the phosphate detergent problems of the late 1960s and early 70s; large doses of phosphate, found in most

detergents at the time, were passing through municipal treatment plants and overloading lakes, causing large

algal blooms to form and subsequently reducing available light, food and oxygen for fish and other aquatic

organisms. While great strides have been taken to address the phosphate problem, it is possible that other

problematic pollutants are being dumped down the drain at the expense of human health and the environment.

SEWAGE TREATMENT

Publicly owned treatment works (POTWs) collect wastewater from homes, commercial buildings, and

industrial facilities and transport it via a series of pipes, known as a collection system, to the treatment plant.

Collection systems may flow entirely by gravity, or may include lift stations that pump the wastewater via a force

main to a higher elevation where the wastewater can then continue on via gravity. Ultimately, the collection

system delivers this sewage to the treatment plant facility. Here, the POTW removes harmful organisms and

other contaminants from the sewage so it can be discharged safely into the receiving stream. Without

treatment, sewage creates bad odors, contaminates water supplies, and spreads disease. Today, more than

16,000 sewage treatment plants exist in the U.S. treating more than 32 billion gallons per day of wastewater.4

Generally, POTWs are designed to treat domestic sewage only. Simply defined, the typical POTW

treatment process consists of primary and secondary treatment, along with some form of solids handling.

Primary treatment is designed to remove large solids (e.g., rags and debris) and smaller inorganic grit. Typical

primary treatment operations include screening and settling. Secondary treatment removes organic

contaminants using microorganisms to consume biodegradable organics. Activated sludge, trickling filters, and

rotating biological contactors are examples of common secondary treatment operations. Depending on effluent

discharge requirements, POTWs may perform other “advanced treatment” operations such as nitrification (to

convert ammonia and nitrite to the less toxic nitrate), denitrification (to convert nitrate to molecular nitrogen),
POTWs and the Need for the Pretreatment Program Introduction to the National Pretreatment Program

-2- Chapter 1

Biochemical Oxygen Demand (BOD)

Total Suspended Solids

Fecal Coliform

pH

Oil and Grease (O&G)

Figure 1. Conventional Pollutants

Interference - a discharge which, alone or in conjunction with

a discharge or discharges from other sources, both:

- Inhibits or disrupts the POTW, its treatment

processes or operations, or its sludge processes, use

or disposal, and

- therefore is a cause of a violation of any NPDES

permit requirement or of the prevention of sewage

sludge use or disposal in compliance with any

applicable requirements.

Pass Through - a discharge which exits the POTW into

waters of the U.S. in quantities or concentrations which,

alone or in conjunction with a discharge or discharges from

other sources, is a cause of a violation of any NPDES permit

requirement.

Figure 2. Interference and Pass Through

physical-chemical treatment (to remove dissolved metals and organics), and disinfection (to kill any remaining

pathogens). After treatment is complete, effluent is discharged to the receiving stream, typically a creek, river,

lake, estuary or ocean. Some POTWs may apply treated effluent directly to golf courses, parkland, or

croplands. 

Both primary and secondary treatment processes generate waste solids, known as sewage sludge or

biosolids. Sludges from the treatment process may be either used productively (i.e., as fertilizer or soil

conditioner) or disposed of in a landfill or incinerated in a dedicated sewage sludge incinerator with the ash also

disposed of in a landfill. 

As described above, POTWs are designed to treat typical

household wastes and biodegradable commercial and biodegradable

industrial wastes. The Clean Water Act (CWA) and EPA define the

contaminants from these sources as conventional pollutants.

Conventional pollutants are identified in Figure 1 and include those

specific pollutants that are expected to be present in domestic

discharges to POTWs. Commercial and industrial facilities may,

however, discharge toxic pollutants that the treatment plant is neither

designed for nor able to remove. 

NEED FOR THE PRETREATMENT PROGRAM

As noted above, POTWs are not designed to treat toxics in industrial waste. As such, these discharges,

from both industrial and commercial sources, can cause serious problems. The undesirable outcome of these

discharges can be prevented using treatment techniques or management practices to reduce or eliminate the

discharge of these contaminants. The act of treating wastewater prior to discharge to a POTW is commonly

referred to as “pretreatment.” The National Pretreatment Program, published in Title 40 Code of Federal

Regulations (CFR) Part 403, provides the regulatory basis to require non-domestic dischargers to comply with

pretreatment standards (effluent limitations) to ensure that the goals of the CWA are attained. As noted in 40

CFR §403.2, the objectives of the National Pretreatment Program are to:

a. Prevent the introduction of pollutants into POTWs which will interfere with the operation of a

POTW, including interference with its use or disposal of municipal sludge;

b. Prevent the introduction of pollutants into POTWs which will pass through the treatment works or

otherwise be incompatible with such works; and

c. Improve opportunities to recycle and

reclaim municipal and industrial

wastewaters and sludges.

The two key terms used in EPA’s objectives for the

National Pretreatment Program, “interference” and

“pass through,” are defined in Figure 2.

As outlined in EPA’s objectives, toxic pollutants

may pass through the treatment plant into the

receiving stream, posing serious threats to aquatic

life, to human recreation, and to consumption of

fish and shellfish from these waters. Pass through

can make waters unswimmable or unfishable in

direct contrast to the goals of the CWA. Or, these

discharges can interfere with the biological activity

of the treatment plant causing sewage to pass

through the treatment plant untreated or

inadequately treated.
Introduction to the National Pretreatment Program POTWs and the Need for the Pretreatment Program

5 EPA Office of Science and Technology, Listing of Fish and Wildlife Advisories (LFWA)

database, 1998.

6 U.S. Environmental Protection Agency, National Pretreatment Program: Report to

Congress, 1991.

Chapter 1 -3-

- air pollution can occur from volatilization of toxic

chemicals in the POTW collection system or

treatment plant, or through incineration of sewage

sludge

- corrosion of collection system and treatment plant

from acidic discharges or discharges containing

elevated levels of sulfate (forming toxic and corrosive

hydrogen sulfide)

- groundwater pollution can occur from leaks in the

collection system or pollutants from contaminated

sewage sludge.

Figure 3. Problems Associated With Toxic Discharges

Even where the POTW has the capability to remove these toxics, the pollutants may end up in the sewage

sludge, thereby limiting sludge disposal options or escalating the cost of disposal. Incinerated contaminated

sludge may release toxic emissions into the atmosphere. Toxic metals removed in primary treatment, while

itself not an inhibitory process, can impact sludge digestion, a process that does utilize bacteria to stabilize

sludge solids. For example, chromium can inhibit reproduction of aerobic digestion microorganisms, thereby

disrupting sludge treatment and producing sludges that must be disposed of with special treatment.

Uncontaminated sludge, on the other hand, can be used as fertilizer or soil conditioner, thereby improving the

productivity of our land. Many municipalities apply sewage sludge to pastureland or parkland, that they could

not do if the sludge were contaminated. 

Volatile organics discharged to sewers can accumulate in the head space of sewers, increasing the

likelihood of explosions that can cause significant damage. Probably the most well known impact from industrial

discharges to POTWs in the U.S. is the explosion in Louisville, KY that occurred in 1981 as the result of

excessive discharges of hexane into the collection system, eventually igniting and destroying more than 3 miles

of sewers and causing $20 million in damage. Discharge limitations and management practices to control slug

discharges have significantly reduced the likelihood of future catastrophes such as the explosion in Louisville.

Discharges of toxic organics can also result in the release of poisonous gas. This occurs most often when

acidic wastes react with other wastes in the discharge. For example, cyanide and acid, both present in many

electroplating operations, react to form highly toxic hydrogen cyanide gas. Similarly, sulfides from leather

tanning can combine with acid to form hydrogen sulfide, another toxic gas. These can be highly dangerous to

POTW collection system operators exposed to such conditions in the performance of their duties. Other

problems associated with toxic discharges are summarized in Figure 3 and further document the urgency of

keeping toxics out of collection systems and POTWs.

The National Pretreatment Program is charged with

controlling the 126 Priority Pollutants from industries

that discharge into sewer systems as described in the

CWA (see Figure 4). These pollutants fall into two

categories; metals and organics:

< Metals, including lead, mercury, chromium, and

cadmium cannot be destroyed or broken down

through treatment or environmental

degradation. Toxic metals can cause different

human health problems such as lead poisoning

and cancer. Additionally, consumption of

contaminated seafood and agricultural food

crops has resulted in exposures exceeding

recommended safe levels.

< Toxic organics, including solvents, pesticides,

dioxins, and polychlorinated biphenyls (PCBs) can be cancer-causing and lead to other serious

ailments, such as kidney and liver damage, anemia, and heart failure. In 1996, EPA’s Office of Science

and Technology (OST) identified 2,193 waterbodies with fish and wildlife advisories, up more than 25

percent from 1995.5

Reductions in pollutants can ensure that industrial development vital to the economic well-being of a

community is compatible with a healthy environment. As will be noted in Chapter 2, many POTWs are

responsible for ensuring that industrial and commercial facilities do not cause problems resulting from their

discharges. In 1991, EPA estimated that 190 to 204 million pounds of metals and 30 to 108 million pounds of

organics were removed each year as a result of pretreatment program requirements.6 This is substantiated by
POTWs and the Need for the Pretreatment Program Introduction to the National Pretreatment Program

-4- Chapter 1

001 Acenaphthene 

002 Acrolein 

003 Acrylonitrile 

004 Benzene 

005 Benzidine 

006 Carbon tetrachloride 

007 Chlorobenzene 

008 1,2,4-trichlorobenzene 

009 Hexachlorobenzene 

010 1,2-dichloroethane 

011 1,1,1-trichloreothane 

012 Hexachloroethane 

013 1,1-dichloroethane 

014 1,1,2-trichloroethane 

015 1,1,2,2-tetrachloroethane 

016 Chloroethane 

018 Bis(2-chloroethyl) ether 

019 2-chloroethyl vinyl ethers

020 2-chloronaphthalene 

021 2,4,6-trichlorophenol 

022 Parachlorometa cresol 

023 Chloroform 

024 2-chlorophenol 

025 1,2-dichlorobenzene

026 1,3-dichlorobenzene 

027 1,4-dichlorobenzene

028 3,3-dichlorobenzidine 

029 1,1-dichloroethylene 

030 1,2-trans-dichloroethylene 

031 2,4-dichlorophenol 

032 1,2-dichloropropane 

033 1,2-dichloropropylene 

034 2,4-dimethylphenol 

035 2,4-dinitrotoluene 

036 2,6-dinitrotoluene 

037 1,2-diphenylhydrazine 

038 Ethylbenzene 

039 Fluoranthene 

040 4-chlorophenyl phenyl ether 

041 4-bromophenyl phenyl ether 

042 Bis(2-chloroisopropyl) ether 

043 Bis(2-chloroethoxy) methane 

044 Methylene chloride 

045 Methyl chloride 

046 Methyl bromide 

047 Bromoform 

048 Dichlorobromomethane

051 Chlorodibromomethane 

052 Hexachlorobutadiene 

053 Hexachlorocyclopentadiene 

054 Isophorone 

055 Naphthalene 

056 Nitrobenzene 

057 2-nitrophenol 

058 4-nitrophenol 

059 2,4-dinitrophenol 

060 4,6-dinitro-o-cresol

061 N-nitrosodimethylamine 

062 N-nitrosodiphenylamine 

063 N-nitrosodi-n-propylamine 

064 Pentachlorophenol 

065 Phenol 

066 Bis(2-ethylhexyl) phthalate 

067 Butyl benzyl phthalate

068 Di-N-Butyl Phthalate 

069 Di-n-octyl phthalate 

070 Diethyl Phthalate 

071 Dimethyl phthalate 

072 benzo(a) anthracene 

073 Benzo(a)pyrene 

074 Benzo(b) fluoranthene

075 Benzo(b) fluoranthene 

076 Chrysene 

077 Acenaphthylene 

078 Anthracene 

079 Benzo(ghi) perylene 

080 Fluorene 

081 Phenanthrene 

082 Dibenzo(,h) anthracene 

083 Indeno (1,2,3-cd) pyrene 

084 Pyrene 

085 Tetrachloroethylene 

086 Toluene 

087 Trichloroethylene 

088 Vinyl chloride 

089 Aldrin 

090 Dieldrin 

091 Chlordane 

092 4,4-DDT 

093 4,4-DDE 

094 4,4-DDD 

095 Alpha-endosulfan 

096 Beta-endosulfan 

097 Endosulfan sulfate 

098 Endrin 

099 Endrin aldehyde

100 Heptachlor 

101 Heptachlor epoxide 

102 Alpha-BHC 

103 Beta-BHC 

104 Gamma-BHC 

105 Delta-BHC 

106 PCB–1242 

107 PCB–1254 

108 PCB–1221 

109 PCB–1232 

110 PCB–1248 

111 PCB–1260 

112 PCB–1016 

113 Toxaphene 

114 Antimony 

115 Arsenic 

116 Asbestos 

117 Beryllium 

118 Cadmium 

119 Chromium 

120 Copper 

121 Cyanide, Total 

122 Lead

123 Mercury 

124 Nickel 

125 Selenium 

126 Silver 

127 Thallium 

128 Zinc 

129 2,3,7,8-TCDD

Figure 4. Priority Pollutants

many POTWs that report significant reductions in the loadings of toxics to their treatment plants that is directly

attributable to implementation of the National Pretreatment Program.
Introduction to the National Pretreatment Program Overview of the National Pretreatment Program

Chapter 2 -5-

Control Authority Pretreatment Audit Checklist and Instructions

Guidance for Conducting a Pretreatment Compliance Inspection

Guidance for Reporting and Evaluating POTW Noncompliance with 

Pretreatment Implementation Requirements

Guidance Manual for POTW Pretreatment Program Development

Pretreatment Compliance Inspection and Audit Manual For Approval Authorities

Procedures Manual for Reviewing a POTW Pretreatment Program Submission

Chapter 2. Applicable EPA Guidance

To restore and maintain the chemical, physical, and biological integrity of the

Nation's waters:

(1) it is the national goal that the discharge of pollutants into the

navigable waters be eliminated by 1985;

(2) it is the national goal that wherever attainable, an interim goal of

water quality which provides for the protection and propagation of

fish, shellfish, and wildlife and provides for recreation in and on the

water be achieved by July 1, 1983;

(3) it is the national policy that the discharge of toxic pollutants in

toxic amounts be prohibited;

(4) it is the national policy that Federal financial assistance be provided

to construct publicly owned waste treatment works;

(5) it is the national policy that Area wide waste treatment management

planning processes be developed and implemented to assure

adequate control of sources of pollutants in each State;

(6) it is the national policy that a major research and demonstration

effort be made to develop technology necessary to eliminate the

discharge of pollutants into the navigable waters, waters of the

contiguous zone, and the oceans; and

(7) it is the national policy that programs for the control of nonpoint

sources of pollution be developed and implemented in an

expeditious manner so as to enable the goals of this Chapter to be

met through the control of both point and nonpoint sources of

pollution.

Figure 5. Section 101 of the Clean Water Act (CWA)

2. OVERVIEW OF THE NATIONAL

PRETREATMENT PROGRAM

THE CLEAN WATER ACT

On October 18, 1972, the 92nd

Congress of the United States

passed the Federal Water Pollution

Control Act Amendments of 1972,

declaring the restoration and

maintenance of the chemical,

physical, and biological integrity of

the Nation's water as a National

objective (see Figure 5). While

procedures for implementing this act (more commonly referred to as the Clean Water Act (CWA)) have

been re-evaluated and modified over time, the 1972 objective has remained unchanged in its 25 year history.

The 1972 Amendments to the CWA established a water quality regulatory approach along with EPApromulgated industry-specific technology-based effluent limitations. The National Pollutant Discharge

Elimination System (NPDES) permit program was established under the CWA to control the discharge of

pollutants from point sources and served as a vehicle to implement the industrial technology-based

standards. To implement pretreatment requirements, EPA promulgated 40 CFR Part 128 in late 1973,

establishing general prohibitions against treatment plant interference and pass through and pretreatment

standards for the discharge of

incompatible pollutants from

specific industrial categories. 

In 1975, several environmental

groups filed suit against EPA

challenging EPA’s criteria for

identifying toxic pollutants, EPA’s

failure to promulgate effluent

standards, and EPA’s failure to

promulgate pretreatment standards

for numerous industrial categories.

As a result of this litigation, EPA

promulgated the General

Pretreatment Regulations at 40

CFR Part 403 on June 26, 1978,

replacing the 40 CFR Part 128

requirements. Additionally, as a

result of the suit, EPA agreed to

regulate the discharge of 65

categories of pollutants (making up

the 126 priority pollutants presented

in Figure 4) from 21 industrial

categories. The list of priority

pollutants is still in effect today (the

original list actually had 129

pollutants, three of which have

since been removed from that list)

while the list of regulated industrial

categories has grown to more than 51 distinct industries. A discussion of industry specific requirements are

provided in Chapter 3.
Overview of the National Pretreatment Program Introduction to the National Pretreatment Program

-6- Chapter 2

§ 403.1 Purpose and applicability

§ 403.2 Objectives of general pretreatment regulations

§ 403.3 Definitions

§ 403.4 State or local law

§ 403.5 National pretreatment standards: Prohibited discharges

§ 403.6 National pretreatment standards: Categorical pretreatment

standards

§ 403.7 Removal credits

§ 403.8 Pretreatment program requirements: Development and

implementation by POTW

§ 403.9 POTW pretreatment programs and/or authorization to revise

pretreatment standards: Submission for approval

§ 403.10 Development and submission of NPDES State pretreatment

programs

§ 403.11 Approval procedures for POTW pretreatment programs and

POTW granting of removal credits

§ 403.12 Reporting requirements for POTW's and industrial users

§ 403.13 Variances from categorical pretreatment standards for

fundamentally different factors

§ 403.14 Confidentiality

§ 403.15 Net/Gross calculation

§ 403.16 Upset provision

§ 403.17 Bypass

§ 403.18 Modification of POTW pretreatment programs

Appendix A: Program Guidance Memorandum

Appendix B: [Reserved]

Appendix C: [Reserved]

Appendix D: Selected Industrial Subcategories Considered Dilute for

Purposes of the Combined Wastestream Formula

Appendix E: Sampling Procedures

Appendix F: [Reserved]

Appendix G: Pollutants Eligible for a Removal Credit

Figure 6. The General Pretreatment Regulations

THE GENERAL PRETREATMENT REGULATIONS

The General Pretreatment Regulations establish responsibilities of Federal, State, and local government,

industry and the public to implement Pretreatment Standards to control pollutants which pass through or

interfere with POTW treatment processes or which may contaminate sewage sludge. The regulations, which

have been revised numerous times since originally published in 1978, consist of 18 sections and several

appendices. A copy of the overall framework for the General Pretreatment Regulations is provided in Figure

6.

The General Pretreatment Regulations apply to all nondomestic sources which introduce pollutants into

a POTW. These sources of “indirect discharge” are more commonly referred to as industrial users (IUs).

Since IUs can be as simple as an unmanned coin operated car wash to as complex as an automobile

manufacturing plant or a synthetic

organic chemical producer, EPA

developed four criteria that define a

Significant Industrial User (SIU). Many

of the General Pretreatment

Regulations apply to SIUs as opposed

to IUs, based on the fact that control of

SIUs should provide adequate

protection of the POTW. 

These four criteria are as follows:

< an IU that discharges an

average of 25,000 gallons

per day or more of process

wastewater to the POTW;

< an IU that contributes a

process wastestream

making up 5 percent or

more of the average dry

weather hydraulic or

organic capacity of the

POTW treatment plant;

< an IU designated by the

Control Authority as such

because of its reasonable

potential to adversely

affect the POTW's

operation or violate any

pretreatment standard or

requirement; or

< an IU subject to Federal

categorical pretreatment

standards.

Unlike other environmental programs that rely on Federal or State governments to implement and

enforce specific requirements, the Pretreatment Program places the majority of the responsibility on local

municipalities. Specifically, section 403.8(a) of the General Pretreatment Regulations states that any POTW

(or combination of treatment plants operated by the same authority) with a total design flow greater than 5

million gallons per day (MGD) and smaller POTWs with SIUs must establish a local pretreatment program.

As of early 1998, 1,578 POTWs are required to have local programs. While this represents only about 15

percent of the total treatment plants nationwide, these POTWs account for more than 80 percent (i.e.,

approximately 30 billion gallons a day) of the national wastewater flow.
Introduction to the National Pretreatment Program Overview of the National Pretreatment Program

Chapter 2 -7-

The General Pretreatment Regulations define the term “Control Authority” as a POTW that administers

an approved pretreatment program since it is the entity authorized to control discharges to its system.

Section 403.10(e) provides States authority to implement POTW pretreatment programs in lieu of POTWs.

Five States have elected to assume this responsibility (Vermont, Connecticut, Alabama, Mississippi, and

Nebraska). In these instances, the State is defined as the Control Authority. 

As described above, all Control Authorities must establish a local pretreatment program to control

discharges from non-domestic sources. These programs must be approved by the “Approval Authority” who

is also responsible for overseeing implementation and enforcement of these programs. As noted in Figure

7 , a total of 44 States/Territories are authorized to implement State NPDES Permit Programs, but only 27

are authorized to be the Pretreatment Program Approval Authority (i.e, those with approved State

pretreatment programs excluding the five §403.10(e) States). In all other States and Territories (including

the 403.10(e) States), EPA is considered to be the Approval Authority. 

POTW PRETREATMENT PROGRAMS

The actual requirement for a POTW to develop and implement a local pretreatment program is a

condition of its NPDES permit. Once the Approval Authority determines that a POTW needs a pretreatment

program, the POTW’s NPDES permit is modified to require development of a local program and submission

of the program to the Approval Authority for review and approval. Consistent with §403.8(f), POTW

pretreatment programs must contain the six minimum elements presented in Figure 8.

In addition to the six specific elements, pretreatment program submissions must include:

C a statement from the City Solicitor (or the like) declaring the POTW has adequate authority to

carry out program requirements;

C copies of statutes, ordinances, regulations, agreements, or other authorities the POTW relies

upon to administer the pretreatment program including a statement reflecting the endorsement

or approval of the bodies responsible for supervising and/or funding the program;

C a brief description and organizational chart of the organization administering the program; and

C a description of funding levels and manpower available to implement the program.

Pretreatment program submissions found to be complete proceed to the public notice process, as

described in Chapter 4, Public Participation and POTW Reporting. Upon program approval, the Approval

Authority is responsible for modifying the POTW’s NPDES permit to require implementation of the approved

pretreatment program. Once approved, the Approval Authority oversees POTW pretreatment program

implementation via receiving annual reports and conducting periodic audits and inspections. As of early

1998, of the 1,578 POTWs required to develop pretreatment programs, 97 percent (1,535) have been

approved.

The National Pretreatment Program regulates IUs through three types of regulatory entities: EPA,

Approval Authorities, and Control Authorities. As noted above, Approval Authorities oversee Control

Authorities while Control Authorities regulate IUs. General responsibilities of each of these three regulatory

entities are presented in Figure 9. 
Overview of the National Pretreatment Program Introduction to the National Pretreatment Program

-8- Chapter 2

State

Approved State 

NPDES Permit Program

Approved State Pretreatment

Program

Alabama 10/19/79 10/19/79*

Arkansas 11/01/86 11/01/86

California 05/14/73 09/22/89

Colorado 03/27/75 --

Connecticut 09/26/73 06/03/81*

Delaware 04/01/74 --

Florida 05/01/95 05/01/95

Georgia 06/28/74 03/12/81

Hawaii 11/28/74 08/12/83

Illinois 10/23/77 --

Indiana 01/01/75 --

Iowa 08/10/78 06/03/81

Kansas 06/28/74 --

Kentucky 09/30/83 09/30/83

Louisiana 08/27/96 08/27/96

Maryland 09/05/74 09/30/85

Michigan 10/17/73 04/16/85

Minnesota 06/30/74 07/16/79

Mississippi 05/01/74 05/13/82*

Missouri 10/30/74 06/03/81

Montana 06/10/74 --

Nebraska 06/12/74 09/07/84*

Nevada 09/19/75 --

New Jersey 04/13/82 04/13/82

New York 10/28/75 --

North Carolina 10/19/75 06/14/82

North Dakota 06/13/75 --

Ohio 03/11/74 07/27/83

Oklahoma 11/19/96 11/19/96

Oregon 09/26/73 03/12/81

Pennsylvania 06/30/78 --

Rhode Island 09/17/84 09/17/84

South Carolina 06/10/75 04/09/82

South Dakota 12/30/93 12/30/93

Tennessee 12/28/77 08/10/83

Texas 09/14/98 09/14/98

Utah 07/07/87 07/07/87

Vermont 03/11/74 03/16/82*

Virgin Islands 06/30/76 --

Virginia 03/31/75 04/14/89

Washington 11/14/73 09/30/86

West Virginia 05/10/82 05/10/82

Wisconsin 02/04/74 12/24/80

Wyoming 01/30/75 --

* - Denotes 403.10(e) State Approval

Figure 7. State Program Approval Status
Introduction to the National Pretreatment Program Overview of the National Pretreatment Program

Chapter 2 -9-

1. Legal Authority

The POTW must operate pursuant to legal authority enforceable in Federal, State or local courts,

which authorizes or enables the POTW to apply and enforce any pretreatment regulations developed

pursuant to the CWA. At a minimum, the legal authority must enable the POTW to:

I. deny or condition discharges to the POTW;

ii. require compliance with pretreatment standards and requirements;

iii. control IU discharges through permits, orders, or similar means;

iv. require IU compliance schedules when necessary to meet applicable

pretreatment standards and/or requirements and the submission of

reports to demonstrate compliance;

v. inspect and monitor IUs;

vi. Obtain remedies for IU noncompliance; and

vii. comply with confidentiality requirements.

2. Procedures

The POTW must develop and implement procedures to ensure compliance with pretreatment

requirements, including:

I. identify and locate all IUs subject to the pretreatment program;

ii. identify the character and volume of pollutants contributed by such

users;

iii. notify users of applicable pretreatment standards and requirements;

iv. receive and analyze reports from IUs;

v. sample and analyze IU discharges and evaluate the need for IU slug

control plans;

vi. investigate instances of noncompliance; and

vii. comply with public participation requirements.

3. Funding

The POTW must have sufficient resources and qualified personnel to carry out the authorities and

procedures specified in its approved pretreatment program.

4. Local limits

The POTW must develop local limits or demonstrate why these limits are not necessary.

5. Enforcement Response Plan (ERP)

The POTW must develop and implement an ERP that contains detailed procedures indicating how the

POTW will investigate and respond to instances of IU noncompliance.

6. List of SIUs 

The POTW must prepare, update, and submit to the Approval Authority a list of all Significant

Industrial Users (SIUs).

Figure 8. Six Minimum Pretreatment Program Elements
Overview of the National Pretreatment Program Introduction to the National Pretreatment Program

-10- Chapter 2

EPA

Headquarters

< Oversees program implementation at all levels

< Develops and modifies regulations for the program

< Develops policies to clarify and further define the program

< Develops technical guidance for program implementation

< Initiates enforcement actions as appropriate

Regions

< Fulfill Approval Authority responsibilities for States without

a State pretreatment program

< Oversee State program implementation

< Initiate enforcement actions as appropriate.

Approval Authorities (EPA Regions and delegated States)

< Notify POTWs of their responsibilities

< Review and approve requests for POTW pretreatment

program approval or modification

< Review requests for site-specific modifications to categorical

pretreatment standards

< Oversee POTW program implementation

< Provide technical guidance to POTWs

< Initiate enforcement actions, against noncompliant POTWs or

industries.

Control Authorities (POTWs, States, or EPA Regions)

< Develop, implement, and maintain approved pretreatment

program

< Evaluate compliance of regulated IUs

< Initiate enforcement action against industries as appropriate

< Submit reports to Approval Authorities

< Develop local limits (or demonstrate why they are not

needed)

< Develop and implement enforcement response plan.

Industrial Users

< Comply with applicable pretreatment standards and reporting

requirements.

Figure 9. Roles and Responsibilities
Introduction to the National Pretreatment Program Pretreatment Standards

Chapter 3 -11-

Guidance Manual For Implementing Total Toxic Organics (TTO) Pretreatment

Standards

Guidance Manual for Preparation and Review of Removal Credit Applications

Guidance Manual for Preventing Interference at POTWs

Guidance Manual for the Identification of Hazardous Wastes Delivered to

Publicly Owned Treatment Works by Truck, Rail, or Dedicated Pipe

Guidance Manual for the Use of Production-Based Pretreatment Standards

and the Combined Wastestream Formula

Guidance Manual on the Development and Implementation of Local Discharge

Limitations Under the Pretreatment Program

Guidance to Protect POTW Workers From Toxic And Reactive Gases And

Vapors

Prelim User’s Guide, Documentation for the EPA Computer Program/Model

for Developing Local Limits for Industrial Pretreatment Programs at

Publicly Owned Treatment Works

Supplemental Manual On the Development And Implementation of Local

Discharge Limitations Under The Pretreatment Program: Residential and

Commercial Toxic Pollutant Loadings And POTW Removal Efficiency

Estimation

Industry-Specific Guides

Aluminum, Copper, And Nonferrous Metals Forming And Metal Powders

Pretreatment Standards: A Guidance Manual

Guidance Manual For Battery Manufacturing Pretreatment Standards

Guidance Manual for Electroplating and Metal Finishing Pretreatment

Standard

Guidance Manual For Iron And Steel Manufacturing Pretreatment Standards

Guidance Manual for Leather Tanning and Finishing Pretreatment Standards

Guidance Manual for Pulp, Paper, and Paperboard and Builders’ Paper and

Board Mills Pretreatment Standards

Chapter 3. Applicable EPA Guidance

3. PRETREATMENT STANDARDS

As described in Chapters 3 and

4, the National Pretreatment Program

identifies specific requirements that

apply to all IUs, additional

requirements that apply to all SIUs,

and certain requirements that only

apply to CIUs. The objectives of the

National Pretreatment Program are

achieved by applying and enforcing

three types of discharge standards:

< prohibited discharge standards

< categorical standards

< local limits.

PROHIBITED DISCHARGE

STANDARDS

All IUs, whether or not subject to

any other National, State, or local

pretreatment requirements, are

subject to the general and specific

prohibitions identified in 40 CFR

§§403.5(a) and (b), respectively.

General prohibitions forbid the

discharge of any pollutant(s) to a

POTW that cause pass through or

interference (Figure 10). Specific

prohibitions forbid eight categories of

pollutant discharges as follows:

(1) discharges containing 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°F (60°C) using the

test methods specified in 40 CFR §261.21;

(2) discharges containing pollutants causing corrosive structural damage to the POTW, but in no

case discharges with a pH lower than 5.0, unless the POTW is specifically designed to

accommodate such discharges;

(3) discharges containing pollutants in amounts causing obstruction to the flow in the POTW

resulting in interference;

(4) discharges of any pollutants released at a flow rate and/or concentration which will cause

interference with the POTW;

(5) discharges of 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°C(104°F) unless the Approval Authority, upon request of the POTW, approves

alternative temperature limits;

(6) discharges of petroleum oil, nonbiodegradable cutting oil, or products of mineral oil origin in

amounts that will cause interference or pass through;
Pretreatment Standards Introduction to the National Pretreatment Program

7 EPA's Considerations of Pollution Prevention in EPA’s Effluent Guideline Development

Process may be consulted for more information on this topic.

-12- Chapter 3

Pass through - A discharge which exits the POTW into waters of

the US in quantities or concentrations which, alone or in

conjunction with a discharge or discharges from other sources, is a

cause of a violation of any requirement of the POTW’s NPDES

permit (including an increase in the magnitude or duration of a

violation.

Interference - A discharge which, alone or in conjunction with a

discharge or discharges from other sources, both (1) inhibits or

disrupts the POTW, its treatment processes or operations, or its

sludge processes, use or disposal; and (2) therefore is a cause of a

violation of any requirement of the POTW’s NPDES permit or of

the prevention of sewage sludge use or disposal.

Figure 10. Interference and Pass Through

(7) discharges 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; and

(8) discharges of trucked or hauled

pollutants, except at discharge points

designated by the POTW.

Compliance with the general and specific

prohibitions is mandatory for all IUs, although

a facility may have an affirmative defense in

any action brought against it alleging a

violation of the general prohibitions or of

certain specific prohibitions [(3), (4), (5), (6)

and (7) above] where the IU can demonstrate

it did not 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 the IU was in compliance with a technicallybased local limit developed to prevent pass through or interference.

These prohibited discharge standards are intended to provide general protection for POTWs. However,

their lack of specific pollutant limitations creates the need for additional controls, namely categorical

pretreatment standards and local limits.

CATEGORICAL STANDARDS

Categorical pretreatment standards (i.e., categorical standards) are national, uniform, technology-based

standards that apply to discharges to POTWs from specific industrial categories (i.e., indirect dischargers)

and limit the discharge of specific pollutants. Categorical pretreatment standards for both existing and new

sources (PSES and PSNS, respectively) are promulgated by EPA pursuant to Section 307(b) and (c) of the

CWA. Limitations developed for indirect discharges are designed to prevent the discharge of pollutants that

could pass through, interfere with, or otherwise be incompatible with POTW operations. Effluent limitations

guidelines (ELGs), developed in conjunction with categorical standards, limit the discharge from facilities

directly to waters of the U.S. (i.e., direct dischargers) and do not apply to indirect dischargers. ELGs

include Best Practicable Control Technology Currently Available (BPT), Best Conventional Pollutant Control

Technology (BCT), and Best Available Technology Economically Achievable (BAT) limitations and New

Source Performance Standards (NSPS). ELGs (i.e., BPT, BCT, BAT, and NSPS) do not apply to indirect

dischargers. The significant difference between categorical standards and effluent limitations guidelines

is that categorical standards account for any pollutant removal that may be afforded through treatment at

the POTW while effluent limitations guidelines do not.

Industries identified as major sources of toxic pollutants are typically targeted for effluent guideline and

categorical standard development. If limits are deemed necessary, EPA investigates affected IUs and

gathers information regarding process operations and treatment and management practices, accounting for

differences in facility size and age, equipment age, and wastewater characteristics. Subcategorization within

an industrial category is evaluated based on variability in processes employed, raw materials used, types

of items produced, and characteristics of wastes generated. Availability and cost of control technologies,

non-water quality environmental impacts, available pollution prevention measures7, and economic impacts

are then identified prior to EPA’s presentation of findings in proposed development documents and

publishing a notice of the proposed regulations in the Federal Register. Based on public comments on the

proposed rule, EPA promulgates (i.e., publishes) the standards (Figure 11).
Introduction to the National Pretreatment Program Pretreatment Standards

Chapter 3 -13-

Data

Collection

Regulatory

Tasks

Proposed

Development

Document

Proposed

Regulations

Public

Comment

Promulgation of

Final

Regulations

Final

Development

Document

Revisions

Figure 11. Development Process of Effluent Guidelines

New Source is defined at 40 CFR §403.3 (k)(1) to mean any building, structure, facility

or installation from which there is or may be a discharge of pollutants, the construction of

which commenced after publication of proposed Pretreatment Standards under Section

307(c) of the Act which will be applicable to such source if Standards are thereafter

promulgated in accordance with that section, provided that:

(i) the building, structure, facility, or installation is constructed at a site at which no

other source is located; or

(ii) the building, structure, facility, or installation totally replaces the process or

production equipment that causes the discharge of pollutants at an existing source; or

(iii) the production or wastewater generating processes of the building, structure, facility

or installation are substantially independent of an existing source at the same site. In

determining whether these are substantially independent, factors such as the extent to

which the new facility is integrated with the existing plant, and the extent to which

the new facility is engaged in the same general type of activity as the existing source

should be considered.

(2) Construction on a site at which an existing source is located results in a modification

rather than a new source if the construction does not create a new building, structure,

facility, or installation meeting the criteria of paragraphs (k)(1)(ii), or (k)(1)(iii) of this

section but otherwise alters, replaces, or adds to existing process or production

equipment.

(3) Construction of a new source as defined under this paragraph has commenced if the

owner or operator has:

(i) begun, or caused to begin as part of a continuous onsite construction program:

(ii) any placement, assembly or installation of facilities or equipment, or

(B) significant site preparation work, including clearing, excavation, or removal of

existing buildings, structures, or facilities which is necessary for the placement,

assembly, or installation of new source facilities or equipment; or

(ii) entered into a binding contractual obligation for the purchase of facilities or

equipment which are intended to be used in its operation within a reasonable time. 

Options to purchase or contracts which can be terminated or modified without

substantial loss, and contracts for feasibility, engineering, and design studies do not

constitute a contractual obligation under this paragraph.

Figure 12. Definition of New Source (40 CFR 403.3(k))

As noted above, categorical pretreatment

standards are developed both for existing

(PSES) and new sources (PSNS). Facilities are

classified as either PSES or PSNS based on the

definition of “new source" set out in 40 CFR

§403.3(k) of the General Pretreatment

Regulations (see Figure 12). Dischargers

subject to PSES are required to comply with

those standards by a specified date, typically no

more than three years after the effective date of

the categorical standard. Users subject to

PSNS, however, are required to achieve

compliance within the shortest feasible time, not

to exceed 90 days from commencement of

discharge. PSNS are often more stringent than

PSES based on the opportunity for new sources to install the best available demonstrated technology and

operate the most efficient production processes.

Congress established an initial list of

21 categorical industries under Section

306 of the CWA of 1972. As a result of

various court decrees and settlement

agreements resulting from litigation, and

from EPA's internal work plan development process, EPA has developed

effluent guidelines (for direct dischargers)

and/or categorical pretreatment standards

(for indirect dischargers) for 51 industrial

categories. Of these industrial categories,

EPA implements pretreatment standards

for 32 categories, and either requires

compliance solely with 40 CFR Part 403

General Pretreatment Regulations or does

not address pretreatment standards for the

remaining categories. Plans for EPA’s

expansion and modification of the list is

detailed in the Effluent Guidelines Plan,

published in the Federal Register

biennially as required in section 304(m) of

the CWA. A list of the industrial

categories that have categorical standards

is provided as Figure 13.

Categorical pretreatment standards

developed can be concentration-based or

mass-based. Concentration-based

standards are expressed as milligrams of

pollutant allowed per liter (mg/l) of wastewater discharged and are issued where production rates for the

particular industrial category do not necessarily correlate with pollutant discharges. Mass-based standards

are generally expressed on a mass per unit of production (e.g., milligrams of pollutant per kilogram of

product produced, pounds of pollutant per million cubic feet of air scrubbed, etc.) and are issued where water

conservation is an important component in the limitation development process. For a few categories where

reducing a facility's flow volume does not provide a significant difference in the pollutant load discharged,

EPA has established both mass- and concentration-based standards. Generally, both a daily maximum

limitation and a long-term average limitation (e.g., average daily values in a calendar month) are established

for every regulated pollutant.
Pretreatment Standards Introduction to the National Pretreatment Program

-14- Chapter 3

Figure 13. Summary of Categorical Pretreatment Standards

Category 40 CFR

Part Subparts Type ofStandard Overview of Pretreatment Standards

Aluminum Forming 467 A-F PSES

PSNS

Limits are production-based, daily maximums and monthly averages. 

Subpart C prohibits discharges from certain operations.

Battery Manufacturing 461 A-G PSES

PSNS

Limits are production-based, daily maximums and monthly 

averages. No discharge is allowed from any process not specifically

identified in the regulations.

Builders' Paper and

Board Mills

431 A PSES

PSNS

Limits are production-based daily maximums. These facilities may

certify they do not use certain compounds in lieu of performing

monitoring to demonstrate compliance.

Carbon Black

Manufacturing

458 A-D PSNS Limits are for Oil & Grease only (no limit duration specified).

Coil Coating 465 A-D PSES

PSNS

Limits are production-based, daily maximums and monthly averages. 

Copper Forming 468 A PSES

PSNS

Limits are production-based, daily maximums and monthly averages.

Electrical and Electronic

Components

469 A-D PSES

PSNS

Limits are concentration-based, daily maximums and 30 day

averages or monthly averages (varies per subpart and pollutant

parameter). Certification is allowed in lieu of monitoring for certain

pollutants when a management plan is approved and implemented.

Electroplating 413 A-B, D-H PSES Limits are concentration-based (or alternative mass-based

equivalents), daily maximums and four consecutive monitoring days

averages. Two sets of limits exist, depending on if facility

discharges more or less than 10,000 gallons per day of process

wastewater. Certification is allowed in lieu of monitoring for certain

pollutants when a management plan is approved and implemented.

Feedlots 412 B PSNS Discharge of process wastewater is prohibited, except when there is

an overflow resulting from a chronic or catastrophic rainfall event.

Fertilizer Manufacturing 418 A-G PSNS Limits may specify zero discharge of wastewater pollutants (Subpart

A), production-based daily maximums and 30-day averages

(Subparts B-E) or concentration-based (Subparts F-G) with no limit

duration specified.

Glass Manufacturing 426 H, K-M PSNS Limits are either concentration- or production-based, daily

maximums and monthly averages.

Grain Mills 406 A PSNS Discharge of process wastewater is prohibited at a flow rate or mass

loading rate which is excessive over any time period during the peak

load at a POTW.

Ink Formulating 447 A PSNS Regulations specify no discharge of process wastewater pollutants

to the POTW.

Inorganic Chemicals

Manufacturing

415 A-BO PSES

PSNS

Limits vary for each subpart with a majority of the limits

concentration-based, daily maximums and 30-day averages, or may

specify no discharge of wastewater pollutants. Numerous subparts

have no pretreatment standards.

Iron and Steel

Manufacturing

420 A-F, H-J, L PSES

PSNS

Limits are production-based, daily maximums and 30 day averages.

Leather Tanning and

Finishing

425 A-I PSES

PSNS

Limits are concentration-based, daily maximums and monthly

averages. In certain instances, production volume dictates

applicable pretreatment standards.

Metal Finishing 433 A PSES

PSNS

Limits are concentration-based, daily maximums and monthly

averages. Certification is allowed for certain pollutants where a

management plan is approved and implemented.
Introduction to the National Pretreatment Program Pretreatment Standards

Figure 13. Summary of Categorical Pretreatment Standards

Category 40 CFR

Part Subparts Type ofStandard Overview of Pretreatment Standards

Chapter 3 -15-

Metal Molding and

Casting

464 A-D PSES

PSNS

Limits are primarily production-based, daily maximums and monthly

averages. Discharges from certain processes are prohibited

(Subparts A-C).

Nonferrous Metals

Forming and Metal

Powders

471 A-J PSES

PSNS

Limits are production-based, daily maximums and monthly averages. 

In some instances, the regulations prohibit the discharge of

wastewater pollutants.

Nonferrous Metals

Manufacturing

421 B-AE PSES

PSNS

Limits are production-based, daily maximums and monthly averages. 

The majority of the Subparts have both existing and new source

limits, with others having solely new source requirements.

Organic Chemicals,

Plastics, and Synthetic

Fibers

414 B-H, K PSES

PSNS

Limits are mass-based (concentration-based standards multiplied by

process flow), daily maximums and monthly averages. Standards

for metals and cyanide apply only to metal- or cyanide-bearing

wastestreams.

Paint Formulating 446 A PSNS Regulations specify no discharge of process wastewater pollutants

to the POTW.

Paving and Roofing

Materials (Tars and

Asphalt)

443 A-D PSNS Limits are for Oil & Grease only (no limit duration specified).

Pesticide Chemicals 455 A, C, E PSES

PSNS

Limits are mass-based (concentration-based standards multiplied by

process flow), daily maximums and monthly averages. Subpart C

specifies no discharge of process wastewater pollutants but provides

for pollution prevention alternatives. Subpart E specifies no

discharge of process wastewater pollutants.

Petroleum Refining 419 A-E PSES

PSNS

Limits are concentration-based (or mass based equivalent), daily

maximums.

Pharmaceutical

Manufacturing

439 A-D PSES

PSNS

Limits are concentration-based, daily maximums and monthly

averages. These facilities may certify they do not use or generate

cyanide in lieu of performing monitoring to demonstrate compliance.

Porcelain Enameling 466 A-D PSES

PSNS

Limits are concentration-based (or alternative production-based),

daily maximums and monthly averages. Subpart B prohibits

discharges certain operations.

Pulp, Paper, and

Paperboard

430 A-G, I-L PSES

PSNS

Limits are production-based daily maximums and monthly averages. 

These facilities may certify they do not use certain compounds in

lieu of performing monitoring to demonstrate compliance. Facilities

subject to Subparts B and E must also implement Best Management

Practices as identified.

Rubber Manufacturing 428 E-K PSNS Limits are concentration- or production-based, daily maximums and

monthly averages.

Soap and Detergent

Manufacturing

417 O-R PSNS Regulations specify no discharge of process wastewater pollutants

to the POTW.

Steam Electric Power

Generating

423 N/A PSES

PSNS

Limits are either concentration-based, daily maximums, or

“maximums for any time”, or compliance can be demonstrated

through engineering calculations.

Timber Products

Processing

429 F-H PSES

PSNS

All PSNS (and PSES for Subpart F) prohibit the discharge of

wastewater pollutants. PSES for Subparts G and H are

concentration-based, daily maximums (with production-based

alternatives).
Pretreatment Standards Introduction to the National Pretreatment Program

8 Where commingled wastestreams combine with nonregulated wastestreams after

treatment, the CWF adjusted limitations are further adjusted by use of the CWF or FWA to

address the untreated, nonregulated wastestreams (Figure 17.) For more detailed

discussion of FWA, see Federal Register preamble language, 51 FR 21454 (June 12, 1986).

-16- Chapter 3

Regulated Unregulated Dilute

Pretreatment

Monitoring

location

POTW

CWF

Figure 14. Combined Wastestream Formula

Regulated Unregulated

Pretreatment

Monitoring

location

POTW

CWF

or

FWA

Unregulated Dilute

Figure 15. CWF vs. FWA

Categorical standards apply to regulated wastewaters, i.e. wastewater from an industrial process that

is regulated for a particular pollutant by a categorical pretreatment standard. Therefore, demonstrating

compliance with categorical pretreatment standards is intended to be based on measurements of

wastestreams containing only the regulated process wastewater. However, recognizing isolation of regulated

wastestreams from nonregulated wastestreams was not always practicable nor desirable, EPA developed

the combined wastestream formula (CWF) and flow

weighted average (FWA) approach for determining

compliance with combined wastestreams.

Pursuant to 40 CFR §403.6(e), the CWF is

applicable where a regulated wastestream combines with

one or more unregulated or dilute wastestreams (Figure

14) prior to treatment. Where nonregulated

wastestreams combine with process streams after

pretreatment, the more stringent approach (whether

CWF or FWA) is used to adjust the limits8 (Figure 15).

The CWF and FWA approaches differ primarily in their

allowances for nonregulated wastestreams. While the

CWF provides a “full credit” (i.e., same pollutant levels

as regulated wastestreams) for unregulated

wastestreams yet no credit for dilute wastestreams, the

FWA requires sampling and analysis of the untreated,

nonregulated wastestreams to determine the credit to be

granted (not to exceed that allowed for the regulated

wastestreams).

Application of the CWF and FWA requires proper identification, classification, and quantification of the

three wastestream types (Figure 16.) Note: in circumstances where boiler blowdown, noncontact cooling

water, stormwater, or demineralized wastestreams

contain a significant amount of a regulated pollutant, and

the treatment of the wastewater with the regulated

wastestream results in substantial reduction of the

regulated pollutant, the Control Authority can classify the

wastestream as unregulated rather than as a dilute

wastestream. Clarification on category-specific

wastestream classifications may be provided by

consulting the applicable regulation(s) and associated

development documents, since wastestream types are

addressed in the effluent guideline and categorical

standard development process. When in doubt, the

Control Authority can always require the CIU to monitor

the wastestream(s) in question to quantify the presence

(or lack thereof) of categorically regulated pollutants.

Reasonably accurate flow data must also be obtained for

each wastestream type flowing through the monitoring

point to ensure categorical pretreatment standards are

adjusted accordingly. Proper application of the CWF or

FWA will result in:

< alternative limits being established for each regulated pollutant in each regulated processes;

< both daily maximum and long-term average (i.e., 4-day, 30-day, or monthly) alternative limits

being calculated for each regulated pollutant;
Introduction to the National Pretreatment Program Pretreatment Standards

Chapter 3 -17-

Regulated

Nonregulated

Unregulated Dilute

Wastewater from an

industrial process that is

regulated for a particular

pollutant by a categorical

pretreatment standard

Wastestreams from an industrial process that are not regulated for a

particular pollutant by a categorical pretreatment standard and are not

defined as a dilute wastestream, e.g.: 

< a process wastestream for which categorical standards

have been promulgated but for which the deadline for

compliance has not yet been reached

< a process wastestream that currently is not subject to

categorical pretreatment standards

< a process wastestream that is not regulated for the pollutant

in question but is regulated for other pollutants.

Wastestreams which have no more than trace or

non-detectable amounts of the regulated pollutant.

Defined in 40 CFR § 403.6(e)(1) of the General

Pretreatment Regulations to include sanitary wastestreams,

demineralized backwash streams, boiler blowdown,

noncontact cooling water, storm water, and process

wastestreams from certain standards based on the findings

that these wastewaters contained none of the regulated

pollutant or only trace amounts of it.

Figure 16. Wastestream Types

Regulated Unregulated Dilute

Pretreatment

Monitoring

location

POTW

Unregulated Dilute

CWF

CWF

or

FWA

Figure 17. Multiple use of the CWF/FWA

< 4-day average limits being adjusted to equivalent monthly average limits when two or more

categorical pretreatment standards apply to the facility and one of the applicable standards is

40 CFR Part 413; and

< calculated alternative limits remaining above the analytical detection limit for that pollutant.

NOTE: If adjusted limit(s) are below the detection limit, the Control Authority shall instruct the

IU to either:

- separate the dilute wastestreams from the regulated wastestreams prior to the combined

treatment facility, or

- segregate all wastestreams entirely.

EPA’s Guidance Manual for the Use of Production Based Pretreatment Standards and the Combined

Wastestream Formula should be consulted for more information on the proper application and adjustment

of categorical pretreatment standards.

Although categorical standards are established based on a particular industrial category, EPA provides

several options for unique circumstances that justify adjustment of categorical standards for an individual

facility:

Removal Credits 40 CFR §403.7 details the

conditions by which a Control Authority may

demonstrate consistent removal of pollutants

regulated by categorical standards at their

POTW, and in so doing, may extend removal

credits to industries on a pollutant-specific basis

to prevent redundant treatment. Removal

credits are available for a pollutant if the

pollutant is regulated by the sewage sludge use

or disposal option employed by the POTW

making the application request, or if the pollutant

is listed in 40 CFR Part 403, Appendix G. Also,

the availability of removal credits is not limited to

Appendix G pollutants for POTWs that dispose

of sewage sludge in municipal solid waste

landfills. Steps for developing such a request

are detailed in EPA’s Guidance Manual for the

Preparation and Review of Removal Credit

Applications.
Pretreatment Standards Introduction to the National Pretreatment Program

-18- Chapter 3

nature and quality of pollutants

in process wastestreams

volume of process

wastewater discharged

nonwater quality environmental impacts

of controlling and treating process

wastestreams

energy requirements for

control and treatment

technology

relation of age, size, land availability and

configuration to equipment and facilities,

process changes, processes employed,

and engineering aspects of application of

control technology

cost of compliance with required

control technology

Figure 18. Factors to Consider for an FDF Variance Request

Fundamentally Different Factors Variance Section 301(n) of the CWA authorizes adjustments of

categorical pretreatment standards for existing sources who demonstrate they have factors which

are fundamentally different from the factors EPA considered during standards development (40 CFR

§403.13). Variance requests must be based solely on information and data submitted during the

development of the categorical standards (Figure 18) and the adjusted effluent limitations must

neither be more nor less stringent than justified by the fundamental difference nor result in a

nonwater quality environmental impact markedly more adverse than the impact considered by EPA

when developing the categorical standard.

Successful requests must detail factors well outside the range considered by EPA in establishing the

standard and not merely factors deviating from the average. Further, differences must not be similar

to a significant number of other facilities in the category. A facility must request a variance in writing

no later than 180 days after publication of a categorical Pretreatment Standard in the Federal

Register.

Net/Gross Adjustment Categorical pretreatment standards can be adjusted to reflect the presence of

pollutants in a CIU’s intake waters (40 CFR §403.15). To obtain a net/gross credit, the CIU must submit

a formal written request to the Control Authority that demonstrates:

< its intake water is drawn from the same body of water that the POTW discharges into (this

can be waived if the Control Authority finds no environmental degradation will result);

< the pollutants present in the intake water will not be entirely removed by the treatment

system operated by the CIU; and

< the pollutants in the intake water do not vary chemically or biologically from the pollutants

limited by the applicable standard.

Inherent in this provision is the requirement that the CIU employ a treatment technology capable of

meeting the categorical pretreatment standard(s). Net/gross adjustments should not be granted to

CIUs that have no treatment. Further, credits are only granted to the extent necessary to meet the

applicable standard(s), up to a maximum value equal to the influent value.
Introduction to the National Pretreatment Program Pretreatment Standards

9

June 26, 1987 letter from Ms. Rebecca W. Hanmer, Deputy Assistant Administrator for

Water.

Chapter 3 -19-

Innovative Technology In accordance with 307(e) of the CWA, existing CIUs choosing to install an

innovative treatment system may receive approval from the Control Authority for up to a two year

extension to their applicable categorical pretreatment standards compliance deadline, provided:

< the innovative treatment has a reasonable potential to result in significantly greater pollutant

removal or equivalent removal at a substantially lower cost than the technologies

considered by EPA when developing the categorical standard;

< the innovative technique has the potential for industry-wide application; and

< the proposed compliance extension will not cause or contribute to the violation of the

POTW's NPDES permit.

While policy has been established for universal categorical variance requests, occasionally, a Control

Authority may merely need assistance to classify a CIU and/or to determine applicable categorical

limitations. Provisions in the General Pretreatment Regulations allow POTWs and IUs to request an EPA

category determination for a specific IU within 60 days after the effective date of the standard in question

[40 CFR §403.6(a)]. Even after the formal timeframe for requesting a categorical determination, EPA (and

states) will assist POTWs and IUs with categorization issues. Such requests, however, do not affect

applicable reporting requirements, including timely requests submitted under 40 CFR §403.6(a).

Additionally, EPA has addressed universal CIU questions posed by Control Authorities in various

memoranda and guidance:

Research and Development (R&D) Facilities Unless specifically addressed in the categorical

regulation or associated development document, R&D facilities where there is no commercial sale

of products from the facility, are not subject to categorical standards.9

 Should an R&D facility need

pollution controls to comply with prohibited discharge standards and/or local limits, the development

documents may serve as guidance on the performance of pollution control technologies.

Certification Statements In lieu of requiring self-monitoring, some standards allow CIUs to certify

that they do not use, generate or discharge a regulated pollutant [e.g. Pulp, Paper and Paperboard

facilities can certify that chlorophenolic compounds are not used (40 CFR Part 430) and

Pharmaceutical Manufacturing facilities can certify that cyanide is not used or generated (40 CFR

Part 439)]. Facilities providing such certifications are still considered CIUs, and therefore are subject

to other pretreatment standards and requirements.

Lack of specific categorical effluent limitations IUs subject to PSES or PSNS that merely require

compliance with 40 CFR Part 403 are not considered CIUs. However, these users may still be

classified as SIUs and are still subject to the general and specific prohibitions and any local limits.

Total Toxic Organics (TTO) Seven categorical regulations currently limit the discharge of TTO:

< 40 CFR Part 413 - Electroplating

< 40 CFR Part 433 - Metal Finishing

< 40 CFR Part 464 - Metal Molding and Casting

< 40 CFR Part 465 - Coil Coating

< 40 CFR Part 467 - Aluminum Forming

< 40 CFR Part 468 - Copper Forming

< 40 CFR Part 469 - Electrical and Electronic Components (Phase I and II)

For each of these standards, TTO refers to the sum of the masses or concentrations of certain toxic

organic pollutants found in the regulated discharge at a concentration greater than 0.01 milligrams

per liter (mg/l). However, the toxic organic pollutants regulated by the TTO limit are specific to each

industrial category. Further, industrial categories may provide some flexibility with regard to

monitoring and/or reporting requirements as follows:
Pretreatment Standards Introduction to the National Pretreatment Program

-20- Chapter 3

Maximum Allowable Headworks Loading Method

(MAHL) Pollutant by pollutant, treatment plant data are

used to calculate removal efficiencies, before applying the

most stringent criteria (i.e., water quality, sludge quality,

NPDES permit, or pollutant inhibition levels) to back

calculate the MAHLs. Subtracting out contributions from

domestic sources, the available industrial loading is then

either evenly distributed among the IUs, or allocated on an

as needed basis to those IUs discharging the pollutant

above background levels. 

Figure 19. MAHL

Maximum Allowable Industrial Load (MAIL) The

MAIL is the total daily mass that a POTW can accept from

all permitted IUs and ensure the POTW is protecting

against pass through and interference.

Figure 20. MAIL

< 40 CFR Parts 413 and 433 allow development and implementation of a Toxic Organic

Management Plan (TOMP) in lieu of routine monitoring while 40 CFR Part 469 allows

development and implementation of a Solvent Management Plan. Upon approval of

these plans by the Control Authority, the CIU can demonstrate compliance with TTO

requirements by certifying that the facility is adhering to this Plan to prevent organics

from being discharged to the POTW. A specific certification statement must be signed

and provided to the Control Authority on a regular basis.

< 40 CFR Parts 464, 465, 467, and 468 allow an option to demonstrate compliance with

an Oil and Grease limit in lieu of demonstrating compliance with a TTO limit. The

option chosen by the CIU must be utilized for all reports required (i.e., BMR, 90-day

compliance report, and periodic compliance reports).

EPA’s Guidance Manual for Implementing Total Toxic Organics (TTO) Pretreatment Standards

should be consulted for more information on TTO.

LOCAL LIMITS

Prohibited discharge standards are designed to protect against pass-through and interference generally.

Categorical pretreatment standards, on the other hand, are designed to ensure that IUs implement

technology-based controls to limit the discharge of pollutants. Local limits, however, address the specific

needs and concerns of a POTW and its receiving waters. Federal regulations at 40 CFR §§403.8(f)(4) and

122.21(j)(4) require Control Authorities to evaluate the need for local limits and, if necessary, implement and

enforce specific limits as part of pretreatment program activities.

Local limits are developed for pollutants (e.g. metals, cyanide, BOD5, TSS, oil and grease, organics) that

may cause interference, pass through, sludge contamination, and/or worker health and safety problems if

discharged in excess of the receiving POTW treatment plant’s capabilities and/or receiving water quality

standards. Typically, local limits are developed to regulate the discharge from all IUs, not just to CIUs, and

are usually imposed at the “end-of-pipe” discharge from an IU (i.e., at the point of connection to the POTW's

collection system). In evaluating the need for local limit development, it is recommended that Control

Authorities:

< conduct an industrial waste survey to identify

all IUs that might be subject to the

pretreatment program;

< determine the character and volume of

pollutants contributed to the POTW by these

industries;

< determine which pollutants have a reasonable

potential for pass through, interference, or

sludge contamination;

< conduct a technical evaluation to determine

the maximum allowable POTW treatment

plant headworks (influent) loading for at least

arsenic, cadmium, chromium, copper, cyanide,

lead, mercury, nickel, silver, and zinc (Figure

19);

< identify additional pollutants of concern; 

< determine contributions from unpermitted sources to determine the maximum allowable treatment plant

headworks loading from “controllable” industrial sources (Figure 20);

< implement a system to ensure these loadings will not be exceeded.

Other local limit approaches available to Control

Authorities include:

Collection System Approach Pollutants found

to be present which may cause fire and
Introduction to the National Pretreatment Program Pretreatment Standards

Chapter 3 -21-

explosion hazards or other worker health and safety concerns, are evaluated for their propensity to

volatilize and are modeled to evaluate their expected concentration in air. Comparisons are made with

worker health exposure criteria and lower explosive limits. Where values are of concern, the Control

Authority may set limits or require development of management practices to control undesirable

discharges. The collection system approach may also consider the prohibition of pollutants with specific

flashpoints to prevent discharges of ignitable wastes. EPA’s Guidance to Protect POTW Workers from

Toxic and Reactive Gases and Vapors details strategies for developing such local limits.

Industrial User Management Practice Plans These plans typically consist of narrative local limits

requiring IUs to develop management practices (e.g., chemical management practices, best

management practices, and spill prevention plans) for the handling of chemicals and wastes. The

need for and suggested contents of such plans may be found in EPA’s Control of Slug Loadings to

POTWs: Guidance Manual, and Spill Prevention, Control, and Countermeasure (SPCC) Information

Guide.

Case-by-Case Discharge Limits These numeric local limits are based on best professional

judgement (BPJ) and available pollution prevention and treatment technologies which are known

to be economically feasible. This approach is most often used when insufficient data are available

to employ the methods outlined above.

Local Specific Prohibitions POTW specific prohibitions may be imposed in addition to the

prohibitions detailed in 40 CFR § 403.5 (a) & (b) to address hydraulic, pollutant specific, and/or

aesthetic concerns; e.g.:

< noxious or malodorous liquids, gases, or solids creating a public nuisance

< wastestreams which impart color and pass through the POTW treatment plant

< storm water, roof runoff, swimming pool drainage

< wastewaters containing radioactive wastes or isotopes

< removed substances from pretreatment of wastewater.

Regardless of the approaches taken by a Control Authority, local limits should correct existing problems,

prevent potential problems, protect the receiving waters, improve sludge use options, and protect POTW

personnel. Additional existing EPA guidance on the subject includes:

< Guidance for Preventing Interference at POTWs

< Guidance Manual on the Development and Implementation of Local Discharge Limitations Under

the Pretreatment Program

< Supplemental Manual on the Development and Implementation of Local Discharge Limitations

Under the Pretreatment Program: Residential and Commercial Toxic Pollutant Loadings and

POTW Removal Efficiency Estimation

< Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents.

Additionally, many EPA Regions and States have developed local limits guidance to address regional and

state issues.
Pretreatment Standards Introduction to the National Pretreatment Program

-22- Chapter 3

General and Specific Prohibitions Categorical Pretreatment Standards Local Limits

Development Established at the Federal level Established at the Federal level Developed by Control Authorities

Reference 40 CFR 403.5(a) & (b) 40 CFR Parts 405-471 Requirements for development found in

40 CFR §§403.5(c) & 403.8(f)(4)

Applicability All IUs CIUs

Commonly all IUs or all SIUs, but

depends on allocation method used

when developing limits.

Purpose

Provide for general protection of the

POTW. May be superseded by

more stringent categorical

pretreatment standards or local

limits.

Minimum standards based on available

treatment technology and pollution prevention

measures for controlling nonconventional and

toxic pollutants that may cause pass through,

interference, etc. at the POTW. May be

superseded by more stringent local limits.

Provide site specific protection for a

POTW and its receiving waters. May

be superseded by more stringent

categorical standards.

All standards are considered pretreatment standards for the purpose of section 307(d) of the Clean Water Act. A POTW is responsible for

identifying standard(s) applicable to each industrial user and applying the most stringent requirements where multiple provisions exist. Compliance

with imposed standards can be achieved through implementation of best management practices, development of a pollution prevention program,

and/or installation of pretreatment.

 Figure 21. Summary of Standards

SUMMARY OF STANDARDS

A summary of all of the pretreatment standards, including general and specific prohibitions, categorical

pretreatment standards, and local limits, is provided as Figure 21.
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -23-

CERCLA Site Discharges to POTWs Guidance Manual

Control of Slug Loadings To POTWs: Guidance Manual

Guidance For Developing Control Authority Enforcement Response

Plans

Guidance Manual for POTWs to Calculate the Economic Benefit of

Noncompliance

Industrial User Inspection and Sampling Manual For POTWs

Industrial User Permitting Guidance Manual

Model Pretreatment Ordinance

Multijurisdictional Pretreatment Programs: Guidance Manual

NPDES Compliance Inspection Manual

POTW Sludge Sampling and Analysis Guidance Document

Pretreatment Compliance Monitoring and Enforcement Guidance

RCRA Information on Hazardous Wastes for Publicly Owned

Treatment Works

U.S. EPA Pretreatment Compliance Monitoring and Enforcement

System: Version 3.0, User’s Guide

Chapter 4. Applicable EPA Guidance

Figure 22. Multijurisdictional Programs

4. POTW PRETREATMENT PROGRAM

RESPONSIBILITIES

Chapter 2 describes the basis

for POTWs to develop pretreatment

programs that implement Federal

pretreatment standards and

requirements, in addition to

protecting any local concerns. This

Chapter provides an overview of

these POTW programs, highlighting

each of the specific program areas

that are to be addressed.

LEGAL AUTHORITY

As discussed in Chapter 2,

POTWs seeking pretreatment

program approval must develop

policy and procedures for program

implementation and establish the

legal authority to implement and

enforce program requirements. The

General Pretreatment Regulations do not provide Control Authorities with the legal authority to carry out their

pretreatment programs; rather the regulations do set forth the minimum requirements for POTWs with

pretreatment programs.

A Control Authority’s legal authority actually derives from State law. Therefore, State law must confer the

minimum Federal legal authority requirements on a Control Authority. Where deficient, State law must be

modified to grant the minimum requirements. 

In order to apply regulatory authority provided by State law, it is generally necessary for the Control

Authority to establish local regulations to legally implement and enforce pretreatment requirements. Where the

Control Authority is a municipality, legal authority is detailed in a Sewer Use Ordinance (SUO), which is usually

part of city or county code. Regional Control Authorities frequently adopt similar provisions in the form of “rules

and regulations.” Likewise, State agencies implementing a State-wide program under 40 CFR §403.10(e) set

out pretreatment requirements as State regulations, rather than as an SUO. [Local regulations cannot give the

Control Authority greater authority than that

provided by State law.] EPA’s 1992 guidance,

EPA Model Pretreatment Ordinance provides

a model for POTWs that are required to

develop pretreatment programs.

As POTW service areas expand, new

contributions may arise fro m

“extrajurisdictional” IUs located outside of the

Control Authority’s legal jurisdiction (see

Figure 22). Multijurisdictional arrangements

require special legal/contractual mechanisms

to ensure adequate authority to implement

and enforce program requirements in these

other jurisdictions. Some state statutes may

provide for general extraterritorial powers

(i.e., a Control Authority is automatically

allowed to regulate extrajurisdictional IUs
POTW Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-24- Chapter 4

contributing to their system). However, the extent to which authorities (i.e., to permit, inspect, enforce, monitor,

etc.) are granted may be somewhat limited, thereby, restricting a Control Authority’s ability to implement and

enforce a program. Where obtaining authority from the State to regulate extrajurisdictional IUs is not feasible,

other options may be pursued:

C Districts The creation of an independent organization (by affected municipalities or the State) which

is authorized to administer and enforce an approved pretreatment program for the entire area in

which it provides services is common in areas where multiple POTWs each serve various

jurisdictions. 

C Agreements Affected Control Authorities may opt to enter into agreements requiring each

municipality to implement and enforce the approved pretreatment program covering all IUs within

their jurisdiction. The Control Authority must retain the means to regulate extrajurisdictional IUs

where the contributing jurisdiction’s efforts are inadequate. It is essential that agreements clearly

define the roles of each party.

C Annexation Where extrajurisdictional IUs lie in unincorporated areas, a Control Authority may

annex or utility annex the service area.

C Contracts A Control Authority may enter into a contract with an extrajurisdictional IU, although

contracts generally limit the enforcement capabilities of the Control Authority. As such, contracts

should only be pursued when all other means fail.

Since procedures for obtaining jurisdiction, creating sanitary districts, annexing service areas, etc. vary

among states, Control Authority personnel should consult with their legal staff to thoroughly examine options

allowed. This may include requesting State legislative changes if necessary. EPA’s 1994 Multijurisdictional

Pretreatment Programs - Guidance Manual provides more information on these jurisdictional issues, including

sample language for agreements and contracts.

INDUSTRIAL WASTE SURVEYS

As part of program development and maintenance, the Federal regulations [40 CFR §403.8(f)(2)(I)] require

Control Authorities to identify and locate all IUs that might be subject to the pretreatment program. While the

General Pretreatment Regulations do not specify how a Control Authority is to accomplish this, it is beneficial

to conduct an initial in-depth survey, then institute measures to update the list continuously. Control Authorities

must ensure that the entire service area is reviewed. This may include IUs located outside the jurisdictional

boundaries of the POTW. In these instances, it may be appropriate to solicit assistance from other jurisdictions

in developing the list of potential dischargers. The types of resources that may be consulted in compiling and

updating the master list include:

C Water and sewer billing records

C Applications for sewer service

C Local telephone directories

C Chamber of Commerce and local business directories

C Business license records

C POTW and wastewater collection personnel and field observations

C Business associations

C Internet

Once IUs are identified, the Control Authority must classify these users to determine if pretreatment

standards and requirements should apply to these facilities. Typically, the Control Authority develops and

distributes an Industrial Waste Survey (IWS) questionnaire to the identified IUs. The IWS questionnaire

requests information regarding IU activities and the nature of wastes discharged. The Control Authority may

opt to send a detailed IWS questionnaire initially or conduct the survey in two phases (i.e., send a screener

requesting basic information to eliminate obvious facilities and then send a detailed IWS to those facilities with

greater potential to be SIUs). Key to the IWS is to identify facilities that are subject to categorical standards

(i.e., CIUs) or otherwise have the potential to impact the POTW (i.e., SIUs).
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -25-

A POTW’s IU inventory should include the name, location, classification, applicable standards, basis for

limits imposed, volume of discharge, control mechanism status, compliance dates and other special

requirements for each IU. The IWS should provide most of the information required to develop the inventory,

although some supplementary information might be required from other sources, such as the permit application

or monitoring data.

The IU inventory must be updated as needed [40 CFR §403.8(f)(2)(I)] and provided to the Approval

Authority as part of the annual report requirement (see POTW Reports section in this Chapter). The on-going

task of maintaining a complete list of IUs requires the Control Authority to implement a system to track existing

IU information and/or classification changes and new user information. Some Control Authorities may

proactively opt to institute a “utility connect questionnaire” program. These types of forms are completed when

a customer applies for new utility service (e.g., water, sewerage, or electricity).

PERMITTING

The General Pretreatment Regulations require all IUs be controlled through permit, order, or similar means

to ensure compliance with applicable pretreatment standards and requirements. Section 403.8(f)(1)(iii)(A-E)

clarifies this requirement to specify that all SIUs be issued a permit or equivalent individual control mechanism

which contains, at a minimum:

< statement of duration (not to exceed five years);

< statement of nontransferabililty (unless outlined provisions are met);

< effluent limitations based on applicable standards;

< self-monitoring, sampling, reporting, notification, and record keeping requirements;

< statement of applicable civil and criminal penalties; and

< a schedule of compliance (where appropriate).

EPA’s 1989 Industrial User Permitting Guidance Manual details procedures for drafting IU discharge permits.

SIU permits issued are site specific and tailored to the unique circumstances of the IU. Permit conditions must

establish clear and explicit requirements for the permittee, to include using such terms such as “shall” and

“must” in lieu of vague terms such as “recommend” or “may”. The Control Authority must document its decisionmaking process when developing permits to ensure defensibility and enforceability. Adherence to sound,

documented procedures will prevent any arbitrary and capricious claims by the permittee. Whether developing

or reissuing a permit, the permitting process consists of three phases:

< Phase I - Collection and verification of information

< Phase II - Data interpretation and fact sheet development

< Phase III - Permit development and issuance.

As part of Phase I, Control Authorities may review and verify information contained in the permit application,

perform an inspection of the IU for confirmation of facts, tally data, and potentially sample and analyze the IU’s

wastestream. Knowledgeable Control Authority personnel, effective communication, and SIU cooperation are

essential to collection of complete and accurate information.

Phase II requires that the Control Authority interpret data and other information and document the permit

decision-making rationale, preferably in a permit fact sheet. Although the contents of a fact sheet will vary by

permittee, fact sheets should provide a justification of all permitting decisions. Typical components of a fact

sheet are provided in Figure 23. Completed fact sheets should be included as part of the permit and provided

to the Permittee to document the soundness of permitting decisions.
POTW Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-26- Chapter 4

For CIUs:

C the basis for the categorical determination(s)

C the identity and flow volume of all wastestreams

generated and discharged to the POTW, and classified

accordingly (i.e., regulated, unregulated, or dilution)

C data used and/or justification for estimates used to

determine categorical limitations

C basis for limits imposed for categorical parameters.

For SIUs/CIUs:

C basis for limits imposed for non-categorical parameters

C rationale for compliance schedules, special plans

required, special conditions, etc.

C basis for monitoring and reporting frequencies.

Figure 23. Components of Permit Fact Sheet 

< Provide current data on IUs

< Confirm or determine IUs' compliance status

< Determine completeness and accuracy of the IU's

performance/compliance records

< Assess the adequacy of the IU's self-monitoring and

reporting requirements

< Assess the adequacy of monitoring locations and IU's

sampling techniques

< Assess the adequacy of imposed limitations and

pollutants of concern

< Develop rapport with IUs

< Evaluate operation and maintenance and overall

performance of an IU's pretreatment system

< Assess the potential for spills and slug loadings

< Evaluate the effectiveness of slug control plan

< Reveal issues requiring action

< Identify noncompliance needing resolution

< Suggest pollution prevention opportunities

< Collect samples

< Obtain data to support enforcement actions

Figure 24. Inspection Considerations

After all permitting decisions are made, the Control

Authority must incorporate those decisions into a

permit. The permit, signed by the specified Control

Authority official is provided to the Permittee for

comment and after comments are addressed, a final

permit is issued to the IU. While many comments may

be easily addressed/resolved by the Control Authority,

occasionally resolution must be obtained through a

formal adjudicatory hearing process where both the

Permittee and Control Authority present their case to a

third party. 

Many POTWs also control contributions from nonSIUs using various means, such as through general

permits issued to an entire industrial sector. These

types of control mechanisms may not necessarily

require compliance with specific pollutant limitations.

For example:

< grease trap maintenance and record keeping

requirements for food establishments;

< maintenance and record keeping requirements for photo processors' silver reclamation units;

< best management practices for mercury recovery by hospitals and dentists.

Industrial sector general permitting programs are common where a real or potential POTW problem is linked

to a particular pollutant discharged (e.g., collection system blockages caused by the discharge of excess oils

and grease from food establishments). POTWs do have authority to enforce their SUO or rules or regulations

against non-SIUs without the need for any type of individual control mechanism. Control Authorities do have

the authority to require non-SIUs to comply with pretreatment standards and requirements contained in their

local regulations and then take appropriate actions against IUs as noncompliance is identified.

INSPECTIONS

Control Authorities are required to inspect and

sample all SIUs a minimum of once per year pursuant

to 40 CFR §403.8(f)(2(v). The frequency with which a

Control Authority actually inspects an SIU may vary

depending on issues such as the variability of an SIU’s

effluent, the impact of their discharge on the POTW,

and their compliance history. Inspection

considerations (see Figure 24) will hinge upon the type

of inspection performed (i.e., scheduled, unscheduled

or demand). EPA’s 1994 Industrial User Inspection

and Sampling Manual for POTWs provides a detailed

reference for inspection procedures and protocols.

Scheduled inspections are useful when the Control

Authority wants to gather specific information from the

facility that necessitates meeting with specific SIU

contacts. However, since scheduled inspections may

interrupt normal operations (e.g., altered production

schedule as a result of preparative work undertaken by

the IU), unscheduled inspections may more accurately

reflect IU compliance status when the inspection is

performed for that reason.
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -27-

POTWs must evaluate, at least once every two years, whether each SIU needs a plan to control slug

discharges (i.e., a discharge of a non-routine, episodic nature, including but not limited to an accidental spill or

non-customary batch discharge). To accurately evaluate the slug potential, Control Authorities likely will have

to examine the SIU during normal operating conditions. If undetected, slug discharges can have serious

impacts on the POTW. EPA’s 1991 Control of Slug Loadings to POTWs Guidance Manual provides a

description of procedures for development, implementation, and review of slug control plans.

Demand inspections are non-routine in nature and occur in response to a concern (e.g., POTW collection

problems downstream from an IU, elevated enforcement actions against an IU, suspicious IU behavior, or an

informer complaint).

Routine Control Authority inspections of SIUs typically consist of three activities; preparation, on-site

assessment, and follow-up.

Preparation - Control Authority personnel should review POTW records for SIUs to be inspected to

familiarize themselves with the facility. Information reviewed may include compliance status, compliance

schedule activities, reports and plans, upcoming report and plan due dates, enforcement activities, permit

applications, waste surveys, previous inspection summaries, categorical regulations, water use/billing

records, and POTW collection system maps. Control Authority personnel should also be familiar with any

specific issues and concerns regarding the POTW treatment plant or collection system problems receiving

the SIU's discharge.

On-site Assessment - Control Authority personnel typically discuss IU operations with IU contacts and

perform a walkthrough of the facility to: update IU information regarding contacts, processes, production

rates, pretreatment, and other waste management activities; review records required to be kept by the IU;

visually verify the need for a slug control plan; and review pretreatment system maintenance, categorical

standards applicable to processes employed, metering and sampling equipment, sampling procedures,

chemicals used, processes employed, management practices, containment structures, locations of floor

drains, etc. Many POTWs have developed a standard inspection questionnaire to facilitate the interview

process and promote consistency during the inspection.

Follow-up - An inspection report should be prepared as soon as possible after the inspector returns to the

office. Unanswered questions, required permit modifications, and/or necessary enforcement actions should

be processed in a timely manner.

Non-routine inspections (e.g., demand) may not encompass all the activities and steps specified above, but,

like routine inspections, these activities may provide the Control Authority an opportunity to collect samples of

the IU’s discharge.

SAMPLING

The General Pretreatment Regulations require Control Authorities to monitor each SIU at least annually and

each SIU to self-monitor semi-annually. As with inspections, the Control Authority should assess site-specific

issues, such as SIU effluent variability, impact of this effluent on the POTW, and the SIU’s compliance history

to determine appropriate sampling frequencies (i.e., if more frequent monitoring is necessary). A more detailed

discussion of IU monitoring requirements is provided in Chapter 5. For more detailed information on sampling

frequencies, consult EPA’s 1994 Industrial User Inspection and Sampling Manual for POTWs.

Sampling is the most appropriate method for verifying compliance with pretreatment standards. Monitoring

location(s) are designated by the Control Authority and must be such that compliance with permitted discharge

limits can be determined. Where possible, the Control Authority should not designate monitoring locations that

are confined spaces or that are difficult to access or difficult to place the automated sampling equipment. 

Monitoring locations should:

< be appropriate for waste stream conditions;

< be representative of the discharge;

< have no bypass capabilities; and

< allow for unrestricted access at all times.
POTW Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-28- Chapter 4

Parameter Sample type Container Preservative Holding time

pH Grab Polyethylene or Glass N/A analyze immediately

BOD Composite Polyethylene or Glass chilled to 4°C 48 hours

TSS Composite Polyethylene or Glass chilled to 4°C 7 days

NH3

 as N Composite Polyethylene or Glass chilled to 4°C, H2SO4 to pH<2 28 days

Oil and Grease Grab Glass chilled to 4°C, HCl or H2SO4 to pH<2 28 days

Cyanide, total Grab Polyethylene or Glass chilled to 4°C, NaOH to a pH >12, and 0.6g

of ascorbic acid if residual chlorine is present

14 days

Metals (total) excl. Cr+6

,

B, and Hg

Composite Polyethylene or Glass HNO3

 to pH<2 6 months

624 (volatiles organics) Grab Amber glass, w/ teflon septum

lid and zero headspace

chilled to 4°C (additional laboratory

preservation required)

7 or 14 days, depending on

specific organic

625 (semi-volatile

organics)

Composite Amber glass w/ teflon lined lid chilled to 4°C (additional laboratory

preservation required)

7 days for sample prep; 40

days for extract

Figure 25. Sample Collection Techniques

Control Authorities should measure flow to allow for collection of flow-proportioned composite samples,

which are required, unless flow-proportional sampling is not feasible. Flow-proportional composite samples are

preferred over time composite samples particularly where the monitored discharge is intermittent or variable.

Desired analyses dictate the preparation protocols, equipment, and collection bottles to use to avoid

contamination of samples or loss of pollutants through improper collection. Sampling for such pollutants as pH,

cyanide, oil and grease, flashpoint, and volatile organic compounds require manual collection of grab samples.

 Similar to composite samples, grab samples must be representative of the monitored discharge and are to be

collected from actively flowing wastestreams. Fluctuations in flow or the nature of the discharge may require

collection of and hand-compositing of more than one grab sample to accurately access compliance. To ensure

defensibility of data, Control Authorities should develop and implement standard operating procedures and

policies detailing sample collection and handling protocols in accordance with 40 CFR Part 136.

Adherence to proper sample collection and handling protocols, 40 CFR Part 136 approved analytical

methodologies, and record keeping requirements [40 CFR §403.12(o)(1)] (see Figure 25) can be verified

through review of field measurement records, chain of custodies, and lab reports. Field measurement records

may require information regarding sample location, condition of and programmed settings for sampling

equipment, wastewater meter readings, and information for such parameters as pH and temperature which

require analysis in the field. Chain of custody forms serve as a link between field personnel and the laboratory

and contain information regarding sample matrix, type, and handling. Lab reports should contain the minimum

information specified in 40 CFR §403.12(o)(1)(ii-iv) as well as any additional information necessary to

demonstrate compliance with 40 CFR Part 136 requirements (e.g., analytical methodology, sample preparation

date and time, time of analysis). Use of standardized forms which prompt recording of information necessary

for demonstrating compliance with applicable requirements, will aid in ensuring it can be used as admissible

evidence in enforcement proceedings or in judicial actions.

ENFORCEMENT

In addition to requirements for permitting, sampling, and inspecting IUs, the General Pretreatment

Regulations also require Control Authorities to review IU reports and plans, and respond to instances of IU

noncompliance in a timely, fair, and consistent manner. Enforcement of pretreatment requirements is a critical

element of the Pretreatment Program, but in the past extenuating circumstances may have prevented POTWs

from taking adequate enforcement. For example, political and economic pressures from local officials could

keep POTW personnel from taking appropriate actions. After this was identified as a major concern, EPA

promulgated regulations in 1990 (55 FR 30082) that require all POTWs with approved pretreatment programs

to adopt and implement an Enforcement Response Plan (ERP). These ERP regulations, at 40 CFR

§403.8(f)(5), establish a framework for POTWs to formalize procedures for investigating and responding to

instances of IU noncompliance. With an approved ERP in place, POTWs can enforce against IUs on a more

objective basis and minimize outside pressures.
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -29-

Q: Is a Control Authority response required for all violations

identified?

Q: Is the IU notified by the Control Authority when a violation is

found?

Q: Is the IU required to respond to each violation with an explanation

and, as appropriate, a plan to correct the violation within a

specified time period?

Q: Where noncompliance continues and/or the IU response is

inadequate, does the Control Authority's response become more

formal and commitments (or schedules, as appropriate) for

compliance established in an enforceable document?

Q: Is the enforcement response selected related to the seriousness of

the violation?

Q: Where the violation constitutes SNC, and is ongoing, is the

minimum response an administrative order?

Figure 26. How Complete is Your ERG?

To evaluate IU compliance, Control Authorities must first identify applicable requirements for each IU. In

general, IU reports (discussed in Chapter 5) and POTW monitoring activities are the basis for POTW evaluation

of IU compliance. Discharge permit limit exceedances, discrepancies, deficiencies, and lateness are all

violations that must be resolved.

To ensure enforcement response is appropriate and that the Control Authority actions are not arbitrary or

capricious, EPA strongly recommends that an Enforcement Response Guide (ERG) be included as part of the

approved ERP. The ERG identifies responsible Control Authority officials, general time frame for actions,

expected IU responses, and potential escalated actions based on:

< the nature of the violation

- pretreatment standards 

- reporting (late or deficient)

- compliance schedules

< magnitude of the violation

< duration of the violation

< frequency of the violation (isolated or recurring)

< (potential) impact of the violation (e.g., interference, pass through, or POTW worker safety)

< economic benefit gained by the violator

< attitude of the violator

The types of questions that dictate whether an

ERP is adequate are presented in Figure 26.

Factors that should be considered in

determining appropriate enforcement responses

to noncompliance events are discussed in detail

in EPA's 1989 Guidance for Developing Control

Authority Enforcement Response Plans. 

The General Pretreatment Regulations set

as an enforcement priority, facilities that meet

the criteria for “Significant Noncompliance

(SNC)” as defined in 40 CFR §403.8(f)(2)(vii)

and depicted in Figure 27. A decision to seek

formal enforcement is generally triggered by an

unresolved instance of SNC, failure to achieve

compliance in a specified time period through

less formal means, or the advice of legal

counsel. SNC evaluations are to be conducted in six-month increments; names of IUs found to be in SNC must

be published in the local newspaper (see Public Participation in this Chapter).

Formal enforcement must be supported by well-documented records of the violations and of any prior efforts

by the Control Authority to obtain compliance. Where effluent limitations have been exceeded, records must

be reviewed to verify compliance with 40 CFR Part 136 test methods. If the IU has received conflicting

information from the Control Authority regarding its compliance status, its status must be clarified in writing.

Although not required, the Control Authority may consider a "show cause" meeting with the IU before

commencing formal enforcement action. Similarly, the regulations do allow, in certain instances, an affirmative

defense for violations.

The range of enforcement mechanisms available to a Control Authority depends on the specific legal

authorities it has been given by city, county, and State legislatures. These mechanisms may range from a

simple telephone call to suits seeking significant criminal penalties. Common enforcement mechanisms include:
POTW Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-30- Chapter 4

An IU is in SNC if its violation meets one or more of

the following criteria (40 CFR 403.8(f)(2)(vii):

(A) Chronic violations of wastewater discharge limits, defined

here as those in which sixty-six percent or more of all of the

measurements taken during a six-month period exceed (by any

magnitude) the daily maximum limit or the average limit for the

same pollutant parameter;

(B) Technical Review Criteria (TRC) violations, defined here as

those in which thirty-three percent or more of all of the

measurements for each pollutant parameter taken during a sixmonth period equal or exceed the product of the daily maximum or

the average limit multiplied by the applicable TRC (TRC = 1.4 for

BOD5

, TSS, fats, oil, and grease, and 1.2 for all other pollutants

except pH);

(C) Any other violation of a pretreatment effluent limit (daily

maximum or longer-term average) that the Control Authority

determines has caused, alone or in combination with other

discharges, interference or pass through (including endangering the

health of POTW personnel or the general public);

(D) Any discharge of a pollutant that has caused imminent

endangerment to human health, welfare or to the environment or

has resulted in the POTW’s exercise of its emergency authority

under 40 CFR § 403.8(f)(1)(vi)(B) of this section to halt or prevent

such a discharge;

(E) Failure to meet, within 90 days after the schedule date, a

compliance schedule milestone contained in a local control

mechanism or enforcement order for starting construction,

completing construction, or attaining final compliance;

(F) Failure to provide, within 30 days after the due date, required

reports such as baseline monitoring reports, 90-day compliance

reports, periodic self-monitoring reports, and reports on

compliance with compliance schedules;

(G) Failure to accurately report noncompliance;

(H) Any other violation or group of violations which the Control

Authority determines will adversely affect the operation or

implementation of the local pretreatment program.

Figure 27. Definition of Significant Noncompliance (SNC)

< Informal notice to IU - This may consist of

a telephone call or "reminder" letter to an

appropriate IU official to notify them of a

minor violation and to seek an explanation.

Such informal notice may be used to

correct minor instances of noncompliance.

< Informal meetings - Used to obtain an

IU's commitment to comply with their

pretreatment obligations or to inform the IU

of stronger enforcement mechanisms

available for unresolved and/or continued

noncompliance.

< Warning letter or Notice of Violation

(NOV) - Written notice to the IU in

response to a violation of pretreatment

standards or requirements. These notices

should request an explanation of the

noncompliance and measures that will be

taken to eliminate future violations.

< Administrative orders and compliance

schedules - These require an IU to "show

cause" to the Control Authority as to why

formal enforcement action should not be

taken and/or sewer service discontinued, or

actions that will be taken to comply with

pretreatment standards or requirements.

Orders as such may be negotiated (i.e.,

Consent Order) or issued at the reasonable

discretion of the Control Authority (i.e.,

Compliance Order). For more egregious or

serious violations, the Control Authority

may issue a Cease and Desist Order. 

< Administrative fines - Assessed by

Control Authorities against IUs for violations

and intended to recapture partial or full

economic benefit for the noncompliance

and to deter future violations. 

< Civil suits - Formal process of filing

lawsuits against IUs to correct violations

and to obtain penalties for violations. Civil

penalty amounts are generally limited

through State or municipal laws. However, 40 CFR §403.8(f)(1)(vi) requires that Control Authorities have

the legal authority to seek or assess civil or criminal penalties of at least $1,000 per day for each violation.

A civil suit for injunctive relief may be used when the IU is unlikely to successfully execute the steps that

the Control Authority believes are necessary to achieve or maintain compliance, when the violation is

serious enough to warrant court action to deter future similar violations, or when the danger presented by

an IU's lengthy negotiation of a settlement is intolerable. 

NOTE: Surcharges are not penalties or fines. Surcharges are intended to recoup the cost of treatment

of wastes by the POTW and must not be used to allow discharges of toxic pollutants that cause

interference or pass through.
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -31-

< Industrial waste questionnaire

< Permit applications, permits and fact sheets

< Inspection reports

< IU reports

< Monitoring data (including laboratory

reports)

< Required plans (e.g., slug control, sludge

management, pollution prevention)

< Enforcement activities

< All correspondence to and from the IU

< Phone logs and meeting summaries.

Figure 28. Types of IU Records Retained

< Legal authority (e.g., SUO)

< Program procedures

< Program approval and modifications

< Copy of POTW NPDES permit(s)

< Local limits development

< ERP

< Correspondence to and from EPA/State

< Annual reports to the Approval Authority

< Public notices

< Funding and resource changes

< Applicable Federal and State regulations

< IU compliance and permitting records

Figure 29. Types of POTW Records Retained

< Criminal prosecution - This type of enforcement is a formal judicial process where sufficient admissible

evidence exists to prove beyond a reasonable doubt that a person has willfully or negligently violated

pretreatment standards or that a person has knowingly made a false statement regarding any report,

application, record, or other document required by the General Pretreatment Regulations. As noted above,

Control Authorities must have the legal authority to seek or assess civil or criminal penalties of at least

$1,000 per day for each violation. Examples of criminal violations include falsification of data and

tampering with sampling results or equipment.

< Termination of service (revocation of permit) - These actions may be pursued by Control Authorities to

immediately halt an actual or threatened discharge to the POTW that may represent an endangerment to

the public health, the environment, or the POTW. Use of these remedies may also be used in bringing

recalcitrant users into compliance.

Regardless of the response taken, the Control Authority should document and track all contact, notices, and

meetings with IUs and IU responses. Control Authority responses and IU responses (or lack thereof) should be

documented and include a record of any direct contact with the IU to attempt to resolve the noncompliance.

Control Authorities must take timely and effective enforcement against violators. Unresolved IU noncompliance

may result in the Approval Authority enforcing directly against the IU and/or the Control Authority. EPA may

also take enforcement action where it deems action by the State or the Control Authority is inappropriate. An

Approval Authority will routinely review the overall performance of a Control Authority in monitoring IUs,

identifying violations, and in enforcing regulations. Performance will be evaluated based on POTW selfmonitoring data, written enforcement response plans, audits, inspections, and pretreatment program reports.

Therefore, it is essential for Control Authorities to effectively manage program information to demonstrate

proper implementation.

Section 505 of the CWA allows citizens to file suit against a Control Authority that has failed to implement

its approved pretreatment program as required by its NPDES permit. The Control Authority may be fined as

well as required to enforce against violations of pretreatment standards and requirements in a court order. 

DATA MANAGEMENT AND RECORD KEEPING

Any IU subject to pretreatment program reporting requirements is required to maintain records resulting from

monitoring in a readily accessible manner for a minimum of 3 years (longer if during periods of any ongoing

litigation). While the means for maintaining files is usually at the discretion of the POTW, all pretreatment

activities should be documented and the documents maintained. Types of IU records that the Control Authority

should maintain are summarized in Figure 28. 

Tracking due dates, submissions, deficiencies,

notifications, etc. and calculating effluent limitation

noncompliance may be facilitated by a computerized data

management system. Similarly, many Control Authorities

use standardized forms (e.g., inspection questionnaires,

chains-of-custody, field measurement records) and

procedures (e.g., sampling, periodic compliance report

reviews) to promote consistency and organization of

program data. 

In addition to specific IU records, Control

Authorities should also maintain general program files

that document specific program development and

implementation activities that are not IU-specific (see

Figure 29). All information should be filed in an orderly

manner and be readily accessible for inspection and

copying by EPA and State representatives or the

public. The pretreatment regulations specify that all

information submitted to the Control Authority or State

must be available to the public without restriction,

except for confidential business information.
POTW Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-32- Chapter 4

1. Modifications that relax POTW legal authorities (as

described in 40 CFR §403.8(f)(1)), except for

modifications that directly reflect a revision to 40

CFR Part 403, and are reported pursuant to 40 CFR

§403.18(d) - Approval procedures for nonsubstantial

modifications;

2. Modifications that relax local limits, except for

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 a pollutant, which are reported pursuant

to 40 CFR §403.18(d) - Approval procedures for

nonsubstantial modifications;

3. Changes to POTW's control mechanism, as

described in 40 CFR §403.(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.

Figure 30. Substantial Modifications of POTW

Pretreatment Programs (40 CFR §403.18)

PUBLIC PARTICIPATION AND POTW REPORTING

Section 101(e) of the CWA establishes public participation as one of its goals, in the development, revision,

and enforcement of any regulation, standard, effluent limitation, plan, or program established by EPA or any

State. The General Pretreatment Regulations encourage public participation by requiring public notices and/or

hearings for program approval, removal credits, program modifications, local limits development and

modifications, and IUs in SNC.

POTW pretreatment program approval requests

require the Approval Authority to publish a notice

(including a notice for a public hearing) in a newspaper

of general circulation within the jurisdiction served by

the POTW. All comments regarding the request as

well as any request for a public hearing must be filed

with the Approval Authority within the specified

comment period, which generally last 30 days. The

Approval Authority is required to account for all

comments received when deciding to approve or deny

the submission. The decision is then provided to the

POTW and other interested parties, published in the

newspaper with all comments received available to the

public for inspection and copying.

Once a local pretreatment program is approved,

the Control Authority must implement that program as

approved. Before there is a significant change in the

operation of a POTW pretreatment program, a program

modification must be initiated. 

For substantial program modifications (see Figure

30), the Control Authority is required to notify the

Approval Authority of the desire to modify its program

and the basis for the change. These changes become

effective upon approval. Approval Authorities (or

POTWs) are required to public notice the request for a

modification, but are not required to public notice the

decision if no comments are received and the request

is approved without changes.

Nonsubstantial modifications must also be

submitted to the Approval Authority for review and

approval, but these changes do not require public notice. And unlike substantial modifications, nonsubstantial

modifications become effective 45 days after submission unless the Approval Authority notifies the POTW

otherwise. 

The POTW is also required to provide annual publication, in the largest daily newspaper in the municipality

in which the POTW is located, of IUs that at any time during the previous twelve months were in SNC. 

In accordance with 40 CFR §403.12(I), Control Authorities are required to submit annual reports to the

Approval Authority documenting program status and activities performed during the previous calendar year.

At a minimum, these reports must contain the following information:
Introduction to the National Pretreatment Program POTW Pretreatment Program Responsibilities

Chapter 4 -33-

1. List of all POTW's IUs including names, addresses, pretreatment standards applicable to each user,

IUs subject to categorical pretreatment standards or a brief explanation of deletions and a list of

additions (with the aforementioned information) keyed to a previously submitted list;

2. A summary of the status of the IU compliance during the reporting period;

3. A summary of compliance and enforcement activities (including inspections) conducted by the

POTW during the reporting period;

4. A summary of changes to the POTW's pretreatment program that have not been previously

reported to the Approval Authority; and

5. Any other relevant information requested by the Approval Authority.

The first report is due within one year after program approval and at least annually thereafter. Approval

Authorities may require additional information, or require that the reports be submitted in a specific format

and/or at an increased frequency (e.g., semi-annually).
Introduction to the National Pretreatment Program Industrial User Pretreatment Program Responsibilities

Chapter 5 -35-

Guidance Manual For Implementing Total Toxic Organics (TTO)

Pretreatment Standards

Guidance Manual for the Identification of Hazardous Wastes Delivered

to Publicly Owned Treatment Works by Truck, Rail, or Dedicated

Pipe

Guidance Manual for the Use of Production-Based Pretreatment

Standards and the Combined Wastestream Formula

Industrial User Inspection and Sampling Manual for POTWs

RCRA Information on Hazardous Wastes for Publicly Owned Treatment

Works

Industry-Specific Guides

Aluminum, Copper, And Nonferrous Metals Forming And Metal Powders

Pretreatment Standards: A Guidance Manual

Guidance Manual For Battery Manufacturing Pretreatment Standards

Guidance Manual for Electroplating and Metal Finishing Pretreatment

Standard

Guidance Manual For Iron And Steel Manufacturing Pretreatment

Standards

Guidance Manual for Leather Tanning and Finishing Pretreatment

Standards

Guidance Manual for Pulp, Paper, and Paperboard and Builders’ Paper

and Board Mills Pretreatment Standards

Chapter 5. Applicable EPA Guidance

5. INDUSTRIAL USER PRETREATMENT

PROGRAM RESPONSIBILITIES

Industrial Users (IUs) are required to

comply with all applicable pretreatment

standards and requirements .

Demonstration of compliance requires

certain IUs to submit reports, selfmonitor, and maintain records. A

summary of the reporting requirements

are provided in Figure 32, with details of

each of these requirements discussed

below. 

REPORTING REQUIREMENTS

Minimum Federal Pretreatment

Program reporting requirements for IUs

are specified in 40 CFR §403.12. Since

Control Authorities are responsible for

communicating applicable standards and

requirements to IUs and for receiving and

analyzing reports, it is essential for

Control Authority personnel to understand

IU reporting and notification requirements

contained in the General Pretreatment

Regulations. These requirements are

summarized below.

Categorical Industrial User (CIU) Reporting Requirements

Baseline Monitoring Report (BMR) [40 CFR §403.12(b)]

Each existing IU that is subject to a categorical pretreatment standard (identified as a Categorical

Industrial User, or CIU) is required to submit a BMR within 180 days after the effective date of the standard.

If a category determination has been requested, the BMR is not due until 180 days after a final administrative

decision has been made concerning the industry's inclusion in the category. The BMR must contain the

following information:

< name and address of the facility and names of the operator and owners

< list of all environmental control permits held by or for the facility

< description of operations, including the average rate of production, applicable Standard Industrial

Classification (SIC) codes, schematic process diagrams, and points of discharge to the POTW from

regulated processes

< flow measurements (average daily and maximum daily) for regulated process wastestreams and

nonregulated wastestreams, where necessary

< pollutant measurements [daily maximum, average concentration, and mass (where applicable)]and

applicable standards

< certification, by a qualified professional, reviewed by a representative of the CIU, of whether

applicable pretreatment standards are being met and, if not, a description of the additional operation

and maintenance (O&M) or pretreatment facilities that are needed to comply with the standards

< a schedule by which the IU will provide the additional O&M or pretreatment needed to comply with

the applicable pretreatment standards.
Industrial User Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

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In addition to the certification noted above, BMRs must be signed and certified as detailed in 40 CFR

§403.12(l) and as described later in this Chapter. If a CIU has already submitted the specific information

required in a permit application or data disclosure form and this information is still current, it need not be

reproduced and resubmitted in the BMR. The BMR is a one-time report, unless changed Federal categorical

standards require submission of a new BMR.

At least 90 days prior to commencement of discharge, new sources are required to submit the above

information, excluding the certification and compliance schedule, and information on the method that the

source intends to use to meet the applicable pretreatment standards.

Compliance Schedule Progress Report [40 CFR §403.12(c)(3)]

A CIU that is not in compliance with applicable categorical standards by the time the standards are

effective often will have to modify process operations and/or install end-of-pipe treatment to comply. Federal

regulations require that the Control Authority develop and impose a compliance schedule for the CIU to

install technology to meet applicable standards. As part of the BMR, a CIU that is unable to comply with

the categorical standards must include a schedule for attaining compliance with the discharge standards.

In no case can the final or completion date in the schedule be later than the final compliance date specified

in the categorical standards. If deemed appropriate, the Control Authority may require compliance earlier

than the final compliance date specified in the Federal regulations. 

Compliance schedules are to contain increments of progress in the form of dates (not to exceed nine

months per event) for commencement and completion of major actions leading to construction and operation

of a pretreatment system and/or in-plant process modifications. Major activities could include hiring an

engineer, completing preliminary analysis and evaluation, finalizing plans, executing a contract for major

components, commencing construction, completion of construction, or testing operation.

In addition, the CIU must submit progress reports to the Control Authority no later than 14 days following

each date in the compliance schedule (and final date for compliance), that include:

< a statement of the CIU's status with respect to the compliance schedule

< a statement of when the CIU expects to be back on schedule if it is falling behind, and the reason

for the delay and steps being taken by the IU to return to the established schedule.

The Control Authority should review these reports as quickly as possible. When a CIU is falling behind

schedule, the Control Authority should maintain close contact with the CIU. If the CIU fails to demonstrate

good faith in meeting the schedule, the Control Authority may consider initiating appropriate enforcement

action to correct the problem(s).

90-Day Compliance Reports [40 CFR §403.12(d)

Section 403.12(d) of the General Pretreatment Regulations requires a CIU to submit a final compliance

report to the Control Authority. An existing source must file a final compliance report within 90 days following

the final compliance date specified in a categorical regulation or within 90 days of the compliance date

specified by the Control Authority, whichever is earlier. A new source must file a compliance report within

90 days from commencement of discharge to the POTW. These reports must contain:

< flow measurements (average daily and maximum daily) for regulated process wastestreams and

nonregulated wastestreams, where necessary

< pollutant measurements [daily maximum, average concentration, and mass (where applicable)] and

applicable standards

< certification, by a qualified professional, reviewed by a representative of the CIU, of whether

applicable pretreatment standards are being met and, if not, a description of the additional operation

and maintenance (O&M) or pretreatment facilities that are needed to comply with the standards.

In addition to the certification noted above, 90-day final compliance reports must be signed and

certified as detailed in 40 CFR §403.12(l) and as described later in this Chapter.

Upset Reports [40 CFR §403.16]
Introduction to the National Pretreatment Program Industrial User Pretreatment Program Responsibilities

Chapter 5 -37-

Upset is defined as an exceptional incident in which there

is unintentional and temporary noncompliance with

categorical standards due to factors beyond the reasonable

control of the CIU. An upset does not include

noncompliance to the extent caused by operational error,

improperly designed or inadequate treatment facilities, lack

of preventative maintenance, or careless or improper

operation. 

Figure 31. Definition of Upset (40 CFR §403.16)

CIUs are allowed an affirmative defense for

noncompliance with categorical standards if they

can demonstrate that the noncompliance was the

result of an upset (Figure 31). Conditions

necessary to demonstrate an upset has occurred

are detailed in 40 CFR §403.16 and require the CIU

to submit at least an oral report to the Control

Authority within 24 hours of becoming aware of the

upset and containing the following information:

< a description of the indirect discharge and

the cause of the noncompliance

< the date(s) and times of the noncompliance

< steps being taken and/or planned to reduce, eliminate, and prevent reoccurrence of the

noncompliance.

If this notification is provided orally, a written report must also be submitted within five days. In any

enforcement action, the IU has the burden of proof in establishing that an upset has occurred. EPA is

responsible for determining the technical validity of this claim.

Categorical and Significant Industrial User (SIU) Reporting Requirements

Periodic Compliance Reports [40 CFR §403.12 (e) & (h)]

After the final compliance date, CIUs are required to report, during the months of June and December,

the self-monitoring results of their wastewater discharge(s). The Control Authority must also require

semi-annual reporting from SIUs not subject to categorical standards. EPA established a minimum

frequency of once every six months, determining this to be adequate for small SIUs or other facilities that

have little potential to cause pass-through or interference or to contaminate the sewage sludge. EPA

assumed that larger IUs and those that have more potential to cause problems would be required by the

Control Authority to sample and report more often. All results for self-monitoring performed must be reported

to the Control Authority, even if the IU is monitoring more frequently than required. Periodic compliance

reports must include:

< nature and concentration of pollutants limited by applicable categorical standards or required by the

Control Authority

< flow data (average and maximum daily) as required by the Control Authority

< mass of pollutants discharged (applicable to CIUs where mass limits have been imposed)

< production rates (applicable to CIUs where equivalent limits have been imposed or where limits

imposed are expressed in allowable pollutant discharged per unit of production).

A Control Authority may choose to monitor IUs in lieu of the IU performing the self-monitoring. 

Additionally, 40 CFR §403.12(e) and (h) require compliance with 40 CFR Part 136 (Guidelines for

Establishing Test Procedures for the Analysis of Pollutants). To demonstrate compliance with these

requirements, IUs may have to submit information regarding sample handling and analytical procedures to

the Control Authority. Development of standardized forms for use by IUs and their testing labs can facilitate

documentation and submission of all required information and can streamline the IU and Control Authority

review process. 

Bypass [40 CFR §403.17]

The General Pretreatment Regulations define “bypass” as the intentional diversion of wastestreams from

any portion of a users treatment facility. If a bypass results in noncompliance, even if it was due to essential

maintenance, the IU must provide a report to the Control Authority detailing a description of the bypass and

the cause, the duration of the bypass, and the steps being taken and/or planned to reduce, eliminate, and

prevent reoccurrence of the bypass.
Industrial User Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-38- Chapter 5

Oral notice must be provided to the Control Authority within 24 hours of the detection of an unanticipated

bypass, with a written follow-up due within 5 days. For an anticipated bypass, the IU must submit notice to

the Control Authority, preferably 10 days prior to the intent to bypass.

Notification of Potential Problems [40 CFR §403.12(f)]

All IUs are required to notify the Control Authority immediately of any discharges which may cause

potential problems. These discharges include spills, slug loads, or any other discharge which may cause a

potential problem to the POTW.

Noncompliance Notification [40 CFR §403.12(g)(2)]

If monitoring performed by an IU indicates noncompliance, the IU is required to notify the Control

Authority within 24 hours of becoming aware of the violation. In addition, the IU must repeat sampling and

analysis and report results of the resampling within 30 days. The repeat sampling is not required if the

Control Authority samples the IU at least once per month or if the Control Authority samples the IU between

the time of the original sample and the time the results of the sampling are received.

Notification of Changed Discharge [40 CFR §403.12(j)]

All IUs are required to promptly notify the Control Authority in advance of any substantial changes in the

volume or character of pollutants in their discharge. 

Notification of Discharge of Hazardous Wastes [40 CFR §403.12(p)]

IUs discharging more than 15 kilograms per month of a waste, which if otherwise disposed of, would be

a hazardous waste pursuant to the RCRA requirements under 40 CFR Part 261 are required to provide a one

time written notification of such discharge to the Control Authority, State, and EPA. IUs discharging any

amount of waste, which if disposed of otherwise, would be an acutely hazardous waste pursuant to RCRA

must also provide this notification. This written notification must contain the EPA hazardous waste number

and the type of discharge (i.e., batch, continuous). If the IU discharges more than 100 kilograms per month

of the hazardous waste, the written notification must also include:

< an identification of the hazardous constituent in the IU's discharge,

< an estimate of the mass and concentration of the constituents in the IU's discharge, and

< an estimate of the mass and concentration of constituents in the IU's discharge in a year.

IUs must also provide a certification accompanying this notification that a waste reduction program is in

place to reduce the volume and toxicity of hazardous wastes to the greatest degree economically practical.

Within 90 days of the effective date of the listing of any additional hazardous wastes pursuant to RCRA, IUs

must provide a notification of the discharge of such wastes.

Signatory and Certification Requirements [40 CFR §403.12(l)]

Pursuant to 40 CFR §403.12(l), BMRs, 90-day compliance reports and periodic compliance reports from

CIUs must be signed by an authorized representative of the facility and contain a certification statement

attesting to the integrity of the information reported. The reports should be signed by one of the following:

< a responsible corporate officer if the IU is a corporation

< a general partner or proprietor if the IU is a partnership or sole proprietorship

< a duly authorized representative of the above specified persons if such authorization is in writing,

submitted to the Control Authority and specifies a person or position having overall responsibility for

the facility where the discharge originates or having overall responsibility of environmental matters

for the facility.

As required in 40 CFR §403.6(a)(2)(ii), the certification statement must read as follows:
Introduction to the National Pretreatment Program Industrial User Pretreatment Program Responsibilities

Chapter 5 -39-

"I certify under penalty of law that this document and all attachments were prepared under my

direction or supervision in accordance with a system designed to assure that qualified personnel

properly gather and evaluate the information submitted. Based on my inquiry of the person or

persons who manage the system, or those persons directly responsible for gathering the information,

the information submitted is, to the best of my knowledge and belief, true, accurate, and complete.

I am aware that there are significant penalties for submitting false information, including the

possibility of fine and imprisonment for knowing violations."

While Federal regulations only require Control Authorities to require these signatures and certifications from

CIUs, many POTWs have found it important to impose these requirements for all IU reports. To facilitate

compliance, many Control Authorities have developed forms that include the certification statement and

signatory requirements for use by all IUs. 

SELF-MONITORING REQUIREMENTS

All SIUs, including CIUs must conduct self-monitoring as part of several different reporting requirements

as noted above. For CIUs, this includes the BMR, 90-day compliance report and periodic compliance reports

(40 CFR §§403.12(b),(d), and (e), respectively). Non-categorical SIUs are required to self-monitor as part

of the periodic reporting requirements (40 CFR §403.12(h)). As noted in 40 CFR §§403.12(g)(4), sample

collection and analysis for all required pretreatment program reports must be conducted using 40 CFR Part

136 procedures and amendments thereto. Refer to Chapter 4 of this manual and EPA’s 1994 Industrial User

Inspection and Sampling Manual for POTWs for additional information on sample collection and analysis

procedures.

Based on the specific pollutants regulated by categorical standards, different types of samples may have

to be collected. For BMR and 90-day compliance reports, a minimum of four grab samples must be

collected for pH, cyanide, total phenols, oil and grease, sulfide, and volatile organics. If these pollutants are

not regulated by the specific categorical standard, monitoring is not required. Twenty-four hour flowproportional composite samples must be collected for all other pollutants. The Control Authority may waive

flow-proportional composite sampling if an IU demonstrates that flow-proportional is not feasible. In these

cases, time-proportional composite samples may be collected.

Self-monitoring for periodic compliance reports must be conducted in accordance with the IU’s discharge

permit requirements. The Control Authority must ensure that these permits specify sampling location(s),

required sampling frequencies, sample types to be collected, sampling and analytical procedures (40 CFR

Part 136), and associated reporting requirements. At a minimum, CIUs must monitor for all categorically

regulated pollutants at least once every six months, although, permits issued by the local Control Authority

may require more frequent monitoring.

In certain instances, CIUs subject to TTO standards may implement alternatives in lieu of monitoring

all regulated toxic organic compounds. A listing of categories that contain TTO standards is provided in

Chapter 3. For example, the electroplating and metal finishing standards allow IUs to monitor only for those

toxic organic compounds that are reasonably expected to be present. Additional TTO guidance related to

the electroplating and metal finishing categories can be found in EPA’s 1984 Guidance Manual for

Electroplating and Metal Finishing Pretreatment Standards. 

For certain industries (i.e., electroplating, metal finishing, and electrical and electronic components)

Control Authorities have the option of allowing the CIU to prepare and implement a Toxic Organic

Management Plan (TOMP) in lieu of periodic monitoring. In those instances, the TOMP should identify all

potential sources from which toxic organic materials could enter the wastestream and propose control

measures to eliminate the possibility. Where a TOMP is allowed, an IU can demonstrate compliance through

adherence to the TOMP and submission of periodic certification statements attesting to the fact that:

“no dumping of concentrated toxic organic pollutants has occurred and that the facility’s

TOMP is being implemented.” 
Industrial User Pretreatment Program Responsibilities Introduction to the National Pretreatment Program

-40- Chapter 5

TOMPs cannot be used in lieu of monitoring for BMRs and 90-day compliance reporting requirements. 

The categorical standards for some industries (i.e., aluminum forming, copper forming, coil coating, and

metal molding and casting) allow IUs to monitor oil and grease (O&G) as an alternative to TTO monitoring.

This option may be used to fulfill TTO monitoring requirements of the BMR, 90-day compliance report, and

periodic compliance reports and allows the IU to determine whether it wants to demonstrate compliance with

the TTO or the O&G standards. A detailed description of TTO monitoring requirements is provided in EPA’s

1985 Guidance Manual for Implementing Total Toxic Organics (TTO) Pretreatment Standards. 

RECORD KEEPING REQUIREMENTS

IUs are required to maintain records of their monitoring activities [40 CFR §403.12(O)]. Information, at

a minimum, shall include the following:

< sampling methods, dates and times

< identity of the person(s) collecting the samples and of the sampling location(s)

< the dates the analyses were performed and the methods used

< the identity of the person(s) performing the analyses and the results of the analyses.

These records shall be retained for at least 3 years, or longer in cases where there is pending litigation

involving the Control Authority or IU, or when requested by the Approval Authority. These records must be

available to the Control Authority and Approval Authority for review and copying. Historically, most Control

Authorities do not dispose of any records, rather older records are archived at an off-site location.
Introduction to the National Pretreatment Program Industrial User Pretreatment Program Responsibilities

Chapter 5 -41-

Figure 32. Industrial User Reporting Requirements

REQUIRED REPORT AND

CITATION

APPLY

TO

REPORT DUE DATE PURPOSE OF REPORT

Baseline Monitoring Report

(BMR) 

40 CFR §403.12(b)(1-7)

CIUs

Existing Source - Within 180 days of

effective date of the regulation or an

administrative decision on category

determination.

New Source - At least 90 days prior to

commencement of discharge.

- To provide baseline information on

industrial facility to Control Authority

- To determine wastewater discharge

sampling points

- To determine compliance status with

categorical pretreatment standards

Compliance Schedule Progress

Reports

40 CFR §403.12(c)(1-3)

All IUs

Within 14 days of each milestone date on

the compliance schedule; at least every 9

months.

- To track progress of the industrial

facility through the duration of a

compliance schedule.

90-Day Compliance Report

40 CFR §403.12(d)

CIUs

Within 90 days of the date for final

compliance with applicable categorical

pretreatment standard; for new sources, the

compliance report is due within 90 days

following commencement of wastewater

discharge to the POTW.

- To notify Control Authority as to

whether compliance with the applicable

categorical pretreatment standards has

been achieved

- If facility is noncompliant, to specify

how compliance will be achieved.

Periodic Compliance Report 

40 CFR §403.12(e) CIUs

Every June and December after the final

compliance date (or after commencement

of a discharge for new sources) unless

frequency is increased by the Control

Authority.

- To provide the Control Authority with

current information on the discharge of

pollutants to the POTW from

categorical industries.

Notice of Potential Problems

40 CFR §403.12(f) All IUs

Notification of POTW immediately after

occurrence of slug load, or any other

discharge that may cause problems to the

POTW.

- To alert the POTW to the potential

hazards of the discharge.

Noncompliance Notification 

40 CFR §403.12(g)(2) All IUs Notification of POTW within 24 hours of

becoming aware of violation.

- To alert the POTW of a known

violation and potential problems which

may occur.

Periodic Compliance Reports

for Noncategorical Users 

40 CFR §403.12(h)

Non-Cat.

SIUs

Every six months on dates specified by the

Control Authority.

- To provide the POTW with current

information on the discharge of 

pollutants to the POTW from industrial

users not regulated by categorical

standards.

Notification of Changed

Discharge

40 CFR §403.12(j)

All IUs

In advance of any substantial changes in

the volume or character of pollutants in the

discharge.

- To notify POTW of anticipated changes

in wastewater characteristics and flow

which may affect the POTW.

Notification of Hazardous

Wastes Discharge

40 CFR §403.12(p)

All IUs For new discharges, within 180 days after

commencement of discharge.

- To notify POTW, EPA, and State of

discharges of hazardous wastes under

40 CFR Part 261.

Upset

40 CFR §403.16 

CIUs

24 hours of becoming aware of the upset 

(5 days where notification was provided

orally)

- To notify the POTW of unintentional

and temporary noncompliance with

categorical standards.

Bypass

40 CFR §403.17

All IUs

10 days prior to date of the bypass or oral

notice within 24 hours of the IU becoming

aware of the bypass with written

notification within 5 day

- To notify the POTW of noncompliance

and potential problems which may

occur
Introduction to the National Pretreatment Program Hauled Wastes

Chapter 6 -43-

CERCLA Site Discharges to POTWs Guidance Manual

Guidance Manual for the Identification of Hazardous Wastes

Delivered to Publicly Owned Treatment Works by

Truck, Rail, or Dedicated Pipe

Industrial User Inspection and Sampling Manual for POTWs

Industrial User Permitting Guidance Manual

RCRA Information on Hazardous Wastes to Publicly Owned

Treatment Works

Guidance Manual for the Control of Waste Hauled to

Publicly Owned Treatment Works

Chapter 6. Applicable EPA Guidance

Domestic septage is defined as either the liquid or solid

material removed from a septic tank, cesspool, portable

toilet, Type III marine sanitation device, or similar

treatment works that holds only domestic sewage. 

Domestic septage does not include liquid or solid material

removed from these systems that receives either

commercial wastewater or industrial wastewater and does

not include grease removed from a restaurant grease trap. 

[40 CFR Part 503.9(f)] 

Figure 33. Definition of Domestic Septage

6. HAULED WASTES

In addition to receiving wastes through the

collection system, many POTWs accept trucked

wastes, and in a few instances, wastes received

via train. As specified in 40 CFR §403.1(b)(1),

pollutants from non-domestic sources which are

transported to the POTW by truck or rail are also

subject to the General Pretreatment Regulations.

Hauled wastes, like wastes received through the

collection system, have the potential to impact the

POTW, making regulatory control of these wastes

necessary. Recent studies have shown an

increasing frequency of uncontrolled discharges to

POTWs from waste haulers. Because of their

unique nature, waste haulers are not regulated in the same way as other types of IUs. Since no specific

Federal regulatory controls exist, some POTWs have developed hauled waste control programs. For more

information on hauled waste, refer to EPA’s 1998 Guidance Manual for the Control of Waste Hauled to

Publicly Owned Treatment Works.

NATURE OF HAULED WASTES

Wastes are hauled to POTWs for several reasons. By far, the majority of hauled waste is domestic

septage (Figure 33). Since these wastes are domestic in nature, treatment at a POTW is the most

appropriate disposal method. Other types of wastes are also regularly hauled to POTWs for a variety of

reasons, such as:

< the facility is located outside the

jurisdictional boundaries of the POTW (e.g.,

located in rural areas) and is not connected

to the collection system,

< the wastes may be known to cause

collection system problems, but can be

treated at the POTW (e.g., grease trap

cleanout wastes),

< the facility is connected to the sewer but

does not have the capacity to discharge the volume of waste generated (e.g., groundwater

remediation activities at an IU),

< a POTW rejects acceptance of a waste from an IU forcing the IU to haul the waste to a different

POTW that agrees to accept the waste.

Common to all these wastes is the fact that the POTW does not know for certain the nature and

concentration of these wastes, as hauled, without implementing some type of control or surveillance

program. 

CONTROL PROGRAMS

Section 403.5(b)(8) of the General Pretreatment Regulations specifically prohibits the introduction of any

trucked or hauled pollutants to the POTW, except at discharge points designated by the POTW. This is the
Hauled Wastes Introduction to the National Pretreatment Program

-44- Chapter 6

only pretreatment requirement specifically addressing hauled wastes. However, many POTWs have

determined that additional controls are necessary to further limit these discharges and to prevent adverse

impacts from these discharges. These control programs include practices such as permitting, sampling,

manifesting, surveillance, and other forms of hauler documentation. In many instances, these control

programs have shifted the hauling of waste from one POTW to other POTWs that are not implementing such

a program. Most often, it is the smaller POTWs that do not have hauler control programs, including many

POTWs that are not even required to implement Pretreatment Programs. The effect of this change from

larger to smaller POTWs and from more to less control is that there has been an increase in negative

impacts to POTWs and receiving streams. Two apparent options for addressing this concern are for: (1) the

smaller and non-pretreatment POTWs to initiate waste hauler control programs; or (2) the larger POTWs

to institute sound control programs that will adequately regulate these wastes yet not drive these haulers to

search for other less sound disposal alternatives. POTW waste hauler control programs should address the

following six elements:

Impact to POTW - Prior to acceptance of a new waste from a hauler, the POTW needs to evaluate the

potential impacts to the POTW from this waste. POTWs may require haulers or generators of hauled waste

to perform a treatability study to demonstrate the effectiveness of treatment on this waste. POTWs must

evaluate the impacts of these waste when evaluating the adequacy of local limits as well as when developing

or revising local limits.

Permitting - A permit is the most direct and efficient method of regulating waste haulers. Permits

provide the opportunity to monitor and regulate haulers based on the nature of the hauled waste and the

potential impacts of that waste on the POTW. Unique permit conditions may include: right of refusal, daily

flow limitations, discharge time limitations, and manifesting requirements.

Discharge Point - As specified in the General Pretreatment Regulations, hauled waste can only be

discharged at points designated by the POTW. This option is to provide the POTW with the ability to control

and observe these discharges at specified locations thereby minimizing the potential for adverse impacts.

Monitoring - The POTW should institute a monitoring program to evaluate the nature and concentration

of discharges. Both POTW monitoring and hauler self-monitoring may be appropriate. Many POTWs

require that all loads of hauled waste must be sampled, but analyses are only performed on a predetermined

percentage of these wastes or when problems occur. Unanalyzed samples are refrigerated and kept for

several weeks or months until the POTW is certain that the waste has not impacted the POTW. The

frequency of sampling may also be dependent on the variability of the waste. Each load from a hauler that

delivers highly variable loads may have to be sampled and analyzed; whereas, a much smaller percentage

may be appropriate for more consistent waste types. As noted earlier, all Federal, State, and local discharge

limitations apply to these wastes. The POTW may also consider inspecting the waste generators to confirm

the source of these wastes.

Hauler Documentation - The POTW should require waste haulers to document the source of wastes

being discharged, potentially including manifests. Manifests should include general hauler information,

information on the waste generator (e.g., name, address, and phone number), the type of wastes collected,

volumes, known or suspected pollutants, and certification that the load is not a hazardous waste. A useful

technique is to contact the waste generators to verify the information on the manifest.

Legal Authority - If not already in place, the POTW’s local ordinance (and approved pretreatment

program) should be modified to add language specifying all of the controls that are applicable to waste

haulers. This will ensure that waste haulers and POTW personnel will know the procedures, expectations,

liabilities, etc. associated with the control program.

In addition to the specific controls described above, POTWs should implement procedures to identify

and eliminate illegal discharges. Procedures may include periodic sewer line sampling, surveillance of

suspected illegal discharge points, education of industries regarding hauled waste, increased enforcement,

and public awareness of illegal dumping.
Introduction to the National Pretreatment Program Hauled Wastes

Chapter 6 -45-

CONCERNS

Every hauled waste discharge has the potential to impact the POTW. Unlike discharges from IUs

connected to the POTW, the makeup of a load of hauled waste is virtually unknown without some type of

monitoring, be it visual or analytical. Even loads of domestic septage can cause problems at a POTW. The

majority of waste haulers are reputable business people who provide a valuable service to the public and

industry; however, the unique attributes of hauled waste can be devastating when unethical haulers dump

incompatible wastes at POTWs. Domestic septage can be partially digested, higher in metals concentrations

than normal domestic wastes, or contain small amounts of household contaminants (e.g., cleaners).

Similarly, disinfectants used in portable toilets have the potential to impact POTW operations. 

Receipt of hauled hazardous waste (as defined in the Resource Conservation and Recovery Act (RCRA))

may not only impact POTW operations, but subject the POTW to additional reporting requirements. The

Domestic Sewage Exclusion, specified in 40 CFR §261.4(a)(1)(ii), provides that hazardous wastes mixed

with domestic sewage are exempt from the RCRA waste regulations. However, hazardous wastes received

by truck or rail (or dedicated pipe) are not exempt from the regulations. POTWs that accept hazardous

wastes from these sources are granted “permit by rule” status under RCRA (40 CFR §270.60(c)) provided

that certain requirements are met. The two most significant conditions are that the POTW must be in

compliance with all of its NPDES permit requirements and the waste must comply with all Federal, State,

and local pretreatment requirements. Nationwide, very few POTWs are knowingly accepting hauled

hazardous waste. 

POTWs should be aware that hauled process wastes from facilities subject to Federal categorical

pretreatment standards are still subject to those standards. This condition highlights the need for POTWs

to have a clear understanding of the source of the waste since applicable standards may be based on the

origin of that waste.

Another potential problematic waste is that from remedial site clean-up operations. Groundwater

contaminated with gasoline or diesel fuel is by far the most common type of waste from these operations.

While these wastes may contain flammable and toxic compounds (e.g., benzene and toluene), another

concern is that large volumes of this waste at a small POTW may actually “flush” the treatment plant,

thereby interfering with treatment operations. Similar concerns also exist for landfill leachate, another

commonly hauled wastestream. Remedial wastes may also come from Comprehensive Environmental

Response, Compensation, and Liability Act (CERCLA) sites, also known as Superfund sites. For CERCLA

guidance, refer to EPA’s 1990 CERCLA Site Discharges to POTWs Guidance Manual. 

Other concerns for POTWs that accept hauled wastes include:

< Illegal dischargers may be discharging toxic pollutants that can pass through or interfere with the

POTW operations;

< Grease trap wastes can coat and inhibit POTW treatment operations;

< Local limits may not account for pollutants in hauled wastes;

< Hauled wastes may contain pollutants for which local limits do not exist; thus, the impacts of this

waste are not readily identifiable;

< Hauled wastes may be unmixed and/or highly concentrated.

For further information on the acceptance of hazardous waste at POTWs, refer to the Guidance Manual for

the Identification of Hazardous Wastes Delivered to Publicly Owned Treatment Works by Truck, Rail, or

Dedicated Pipe.
Introduction to the National Pretreatment Program Pollution Prevention

10 For example, a wet scrubber is used to remove most of the metal emissions to the air. The

metals are captured in the scrubber water. This water must be treated to remove the metals

prior to discharge. The treatment process produces a sludge that contains most of the metals

that were once in the water. The sludge is disposed in a landfill. The metals have been

dispersed to the air, water, and land.

Chapter 7 -47-

Guides to Pollution Prevention: Municipal Pretreatment Program

NPDES Compliance Inspection Manual

Chapter 7. Applicable EPA Guidance

7. POLLUTION PREVENTION

As the nation's environmental laws and

regulations have developed over the past

three decades, a new paradigm has shifted

the approach to waste management. Initially,

EPA focused on managing the pollution

generated through treatment and disposal in

an environmentally safe manner. However, we have learned that conventional treatment and disposal can

transfer pollutants from one medium to another with no net reduction.10 In striving to meet new and often

more stringent environmental laws, industries have found ways to reduce or prevent pollution at the source.

Recognizing that source reduction is more desirable than treatment and disposal, EPA now emphasizes

preventing or eliminating the generation of waste. The Pollution Prevention Act of 1990 (PPA) established

pollution prevention (referred to as “P2") as a national objective.

Pollution prevention is indirectly defined in the PPA as source reduction. Source reduction is any

practice that reduces or eliminates the creation of pollutants. Thus, the amount of any hazardous substance,

pollutant, or contaminant entering any waste stream or otherwise released into the environment (including

fugitive emissions) is reduced prior to recycling, treatment, or disposal. Source reduction can be achieved

through equipment or technology modifications, process or procedural modifications, reformulation or

redesign of products, substitution of raw materials, or improvements in housekeeping, maintenance, training,

or inventory control.

The PPA established a pollution prevention hierarchy as national policy, declaring that:

< Pollution should be prevented or reduced at the source.

< Pollution that cannot be prevented should be recycled in an environmentally safe manner.

< Pollution that cannot be prevented or recycled should be treated in an environmentally safe manner.

< Disposal or other release into the environment should be employed only as a last resort and should

be conducted in an environmentally safe manner.

Thus, under the Pollution Prevention Act, recycling, energy recovery, treatment, and disposal are not

included within the definition of pollution prevention. However, some practices commonly described as "inprocess recycling" may qualify as pollution prevention. Although recycling is not pollution prevention, as

indicated in the hierarchy, it is the next desirable practice where pollution cannot be prevented or reduced.

Recycling conducted in an environmentally sound manner shares many of the advantages of prevention for

it can reduce the need for treatment or disposal and conserve energy and resources.

EPA’s Office of Pollution Prevention and Toxic Substances (OPPTS) developed a pollution prevention

strategy for incorporating pollution prevention concepts into EPA’s ongoing environmental protection efforts.

The specific objectives of the strategy are to provide guidance and direction for efforts to incorporate

pollution prevention within EPA’s existing regulatory and nonregulatory programs, and to set forth an

initiative to achieve specific objectives in pollution prevention within a reasonable time frame. EPA’s

numerous activities include the following: 
Pollution Prevention Introduction to the National Pretreatment Program

-48- Chapter 7

< Coordinating development of regulations that will help identify the potential for multi-media

prevention strategies and that reduce end of pipe compliance costs

< Examining the use of pollution prevention in enforcement actions and negotiations

< Investigating the feasibility of overcoming identified regulatory barriers to encourage cost

effective(source reduction) strategies

< Working with State and local governments and trade associations to promote pollution prevention

among small and medium size business that often lack the capital to make changes

< Investing in outside programs, usually States, by providing grant funds for the reduction of target

chemicals, the agricultural and transportation industry, etc.

< Providing scientific and technical knowledge necessary to implement pollution prevention initiatives

on a cross media basis, pursuant to the Pollution Prevention Research Strategic Plan.

POLLUTION PREVENTION AND THE PRETREATMENT PROGRAM

Although pollution prevention is not a required element of the National Pretreatment Program, source

reduction is not new to the Program. The Pretreatment Program is designed to prevent toxic pollutants from

being discharged to POTWs through controls on the sources that discharge these pollutants. Thus, pollution

prevention may be considered an extension of current pretreatment program implementation activities. For

example, Pretreatment Programs have the authority to require and enforce waste management practices

in order to meet NPDES permit requirements and eliminate interference with treatment facilities. Requiring

slug control plans and developing compliance schedules for improved operation and maintenance (O&M

)procedures are examples of pollution prevention activities that have long been required by many Control

Authorities. Other pretreatment program implementation tools available to make pollution prevention a more

integral part of a pretreatment program include:

< Inspections - Pretreatment personnel are usually quite familiar with processes performed at their

local industrial facilities and have exposure to a variety of industries performing the same or similar

processes; therefore, they can easily disseminate (nonconfidential) information about actual pollution

prevention measures implemented as well as identify new P2 opportunities.

< Permits - Where local regulations allow, questions about pollution prevention measures and plans

can be made part of the permit application process. Also, a permittee may be required to undergo

a pollution prevention assessment and /or develop a pollution prevention plan as a condition of the

permit.

< Local limits - POTWs near or above maximum allowable headworks loadings may institute POTW

wide-pollution prevention programs to reduce specific pollutants.

< Enforcement negotiations - A pollution prevention audit may be required through a consent or

compliance order, or implementation of pollution prevention measures may be required as part of

a settlement.

Several Control Authorities have implemented these pollution prevention activities. For example, the

City of Palo Alto, CA established a silver local limit for photoprocessors and Best Management Practices

(BMPs) for automotive facilities. To reduce mercury loadings from dental offices, Western Lake Superior

Sanitary Sewer District (WLSSD) in Duluth, MN developed and implemented pollution prevention BMPs.

These and many other POTWs that have successfully integrated pollution prevention into their pretreatment

programs have become recognized environmental leaders in their communities. 

While pollution prevention activities can be unique to each POTW, the following are key elements of

successful pollution prevention programs:

< Integrate pollution prevention into existing activities - POTWs that view pollution prevention

as an enhancement (instead of an additional requirement) to their existing pretreatment programs

make small modifications to existing pretreatment activities efficiently and effectively. 

< Start small - POTWs that slowly phase in new pollution prevention activities overcome impediments

such as limited resources and resistance. Implementing small changes gradually can be done with
Introduction to the National Pretreatment Program Pollution Prevention

Chapter 7 -49-

C Decrease pollutant loadings to water, air, and sludge

C Decrease pollutant loadings to POTW that result in lower

O&M costs and reduces or eliminates need for capital

expenditures for POTW treatment plant expansions

C Enables continued or expanded growth in the community

without harm to the environment.

Figure 34. Benefits of Pollution Prevention to POTWs

minimal resources. This approach enables pollution prevention activities to become an accepted

integral part of the pretreatment program.

< Define attainable goals and measure success - Short-term, narrowly focused efforts have a

greater chance of succeeding. For example, POTWs have targeted a specific pollutant and group

of industries, established specific pollution prevention activities, and monitored the progress and

success of these activities. With each new success recorded, the benefits of pollution prevention

are illustrated and the demand for further activities will grow. 

< Provide incentives - Incentives are effective tools for persuading users to investigate pollution

prevention opportunities. POTWs have used a wide range of tools such as public recognition of

pollution prevention achievements and reduction of regulatory requirements.

BENEFITS OF POLLUTION PREVENTION

For both IUs and POTWs, pollution prevention has many benefits (Figures 34 and 35) that can be

broadly categorized under tangible economic rewards and public goodwill and support. For example,

pollution prevention:

< Creates cost savings

< Enhances process efficiency

< Avoids or reduces regulatory costs

< Reduces future liabilities

< Improves protection of worker health

< Improves public image. 

Although the numerous benefits make

pursuing pollution prevention attractive, implementation of source reduction in some situations may not be

possible. Before implementing a pollution prevention practice, the benefits and barriers of the potential

opportunity must be evaluated. Common impediments include the following:

< Technology

- Decrease product quality

- Unable to change raw materials because of currently available technology

< Financial

- Incur high costs associated with implementing alternatives (i.e., new equipment or materials,

or personnel and training)

- Loss due to downtime during switch overs and start ups

- Foreign competitors may have an economic advantage if they are not obligated to comply with

US regulations

- Binding contracts with existing waste haulers and Treatment, Storage and Disposal (TSD)

facilities may exist

< Organizational

- Lack of or poor communication between persons possessing the knowledge and ideas for

improvements and those that can actually implement the changes

- Limited personnel or internal resources available to investigate and/or make changes

- Lack of coordination and cooperation among divisions in the corporation

< Behavioral

- Alternatives may be considered inconvenient by personnel (e.g., dry sweeping then a wet wash

down as opposed to just a wet wash down)
-50-

C Regulatory

- Elimination of regulated wastewater discharges, and

hence, monitoring requirements

- Reduced paperwork requirements for waste hauling

and treatment

- Compliance with RCRA reports on waste reduction

(i.e., companies generating RCRA wastes are required

to certify that they have a program to reduce the

volume and toxicity of hazardous waste generated)

- Compliance with land disposal restrictions and bans

C Environmental

- Minimization of material emissions to all media

resulting in reduced health risks to workers and the

community

C Financial

- Reduced landfill and treatment costs due to less waste

being generated (includes reduced transportation costs

as well)

- Reduced raw material and manufacturing costs (e.g.,

by preventing spills or leaks, improving equipment

maintenance and inventory control techniques, reuse,

etc. raw materials are handled more efficiently and do

not have the chance to become waste. With a greater

percentage of raw material going into process, raw

material use goes down in relation to volume of

product produced)

- Increased manufacturing efficiency and productivity

and improved product quality with fewer offspec

products

C Compliance and public relations

- Achieving compliance with local limits and categorical

standards

- Reducing waste and implementing best management

practices can improve public and community relations.

Figure 35. Benefits of Pollution Prevention to IUs

< Regulatory

- Concentrating a pollutant for recycling

may classify it as a hazardous waste

(e.g., silver). As such, an industrial

user may choose to discharge the

pollutant rather than be subject to

regulations regarding the handling,

treatment and disposal of a hazardous

waste.

POLLUTION PREVENTION ASSISTANCE

With the creation of the PPA came an

abundance of pollution prevention related

assistance. This includes direct technical

assistance, training courses, and a variety of

publications. POTWs can find further information

on integrating pollution prevention into their

pretreatment programs in EPA’s 1993 Guides to

Pollution Prevention - Municipal Pretreatment

Programs. Specific industry trade associations and

university technology transfer and outreach

departments usually are aware of pollution

prevention assistance materials, specific pollution

prevention opportunities, and the costs and

success of implementing these. Some further

sources that disseminate pollution prevention

information include:

< Pollution Prevention Information

Clearinghouse (PPIC) - a free, nonregulatory

clearinghouse available to the public which

focuses on source reduction and recycling for

industrial toxic wastes.

< State Programs - provide technical assistance

to conduct pollution prevention assessments,

develop guidance manuals on conducting

these assessments, actually conduct these assessments, provide assistance in developing POTW-wide

pollution prevention plans, provide training for industry, State and POTW personnel, and offer grants

for pollution prevention projects.

< Envirosense - an on-line computer system (internet address: es.inel.gov) of summary information for

PPIC documents, includes pollution prevention news, upcoming events, and mini-exchanges (discrete

pollution prevention topic areas, pollution prevention databases, and message center).

< National Institute of Standards and Technology (NIST) - an office of the Department of Commerce,

NIST develops technology to improve product quality, modernize manufacturing processes, ensure

product reliability, and facilitate rapid commercialization of products based on new scientific discoveries.

NIST web sites for different industry sectors are available. For example, the metal finishing web site

(i.e., the National Metal Finishing Resource Center) is found at “www.nmfrc.org.”

8. BIBLIOGRAPHY
Introduction to the National Pretreatment Program Bibliography

Chapter 8 -51-

TITLE DATE EPA Number NTIS Number ERIC Number

Aluminum, Copper, And Nonferrous Metals Forming And

Metal Powders Pretreatment Standards: A Guidance

Manual

December 1989 800-B-89-001 PB91-145441 W119

CERCLA Site Discharges to POTWs Guidance Manual August 1990 540-G-90-005 PB90-274531 W150

Control Authority Pretreatment Audit Checklist and

Instructions

May 1992 -- -- --

Control of Slug Loadings To POTWs: Guidance Manual February 1991 21W-4001 -- --

Environmental Regulations and Technology: The

National Pretreatment Program

July 1986 625-10-86-005 PB90-246521 W350

Guidance for Conducting a Pretreatment Compliance

Inspection

September 1991 300-R-92-009 PB94-120631 W273

Guidance For Developing Control Authority Enforcement

Response Plans

September 1989 -- PB90-185083/AS --

Guidance for Reporting and Evaluating POTW

Noncompliance with Pretreatment Implementation

Requirements

September 1987 -- PB95-157764 W304

Guidance Manual For Battery Manufacturing

Pretreatment Standards

August 1987 440-1-87-014 PB92-117951 W195

Guidance Manual for Electroplating and Metal Finishing

Pretreatment Standard

February 1984 440-1-84-091-G PB87-192597 W118

Guidance Manual For Implementing Total Toxic

Organics (TTO) Pretreatment Standards

September 1985 440-1-85-009-T PB93-167005 W339

Guidance Manual For Iron And Steel Manufacturing

Pretreatment Standards

September 1985 821-B-85-001 PB92-114388 W103

Guidance Manual for Leather Tanning and Finishing

Pretreatment Standards

September 1986 800-R-86-001 PB92-232024 W117

Guidance Manual for POTW Pretreatment Program

Development

October 1983 -- PB93-186112 W639

Guidance Manual for POTWs to Calculate the Economic

Benefit of Noncompliance

September 1990 833-B-93-007 -- --

Guidance Manual for Preparation and Review of

Removal Credit Applications

July 1985 833-B-85-200 -- --

Guidance Manual for Preventing Interference at POTWs September 1987 833-B-87-201 PB92-117969 W106

Guidance Manual for Pulp, Paper, and Paperboard and

Builders’ Paper and Board Mills Pretreatment Standards

July 1984 -- PB92-231638 W196

Guidance Manual for the Identification of Hazardous

Wastes Delivered to Publicly Owned Treatment Works

by Truck, Rail, or Dedicated Pipe

June 1987 -- PB92-149251 W202

Guidance Manual for the Use of Production-Based

Pretreatment Standards and the Combined Wastestream

Formula

September 1985 833-B-85-201 PB92-232024 U095

Guidance Manual on the Development and

Implementation of Local Discharge Limitations Under the

Pretreatment Program

December 1987 833-B-87-202 PB92-129188 W107

Guidance on Evaluation, Resolution, and Documentation

of Analytical Problems Associated with Compliance

Monitoring

June 1993 821-B-93-001 -- --

Guidance to Protect POTW Workers From Toxic And

Reactive Gases And Vapors

June 1992 812-B-92-001 PB92-173236 W115

Guides to Pollution Prevention: Municipal Pretreatment

Programs

October 1993 625-R-93-006 -- --
Bibliography Introduction to the National Pretreatment Program

TITLE DATE EPA Number NTIS Number ERIC Number

-52- Chapter 8

Industrial User Inspection and Sampling Manual For

POTWs

April 1994 831-B-94-001 PB94-170271 W305

Industrial User Permitting Guidance Manual September 1989 833-B-89-001 PB92-123017 W109

Model Pretreatment Ordinance June 1992 833-B-92-003 PB93-122414 W108

Multijurisdictional Pretreatment Programs: Guidance

Manual

June 1994 833-B-94-005 PB94-203544 W607

National Pretreatment Program: Report to Congress July 1991 21-W-4004 PB91-228726 W694

NPDES Compliance Inspection Manual September 1994 300-B-94-014 -- --

POTW Sludge Sampling and Analysis Guidance

Document

August 1989 833-B-89-100 -- --

Prelim User’s Guide, Documentation for the EPA

Computer Program/Model for Developing Local Limits for

Industrial Pretreatment Programs at Publicly Owned

Treatment Works, Version 5.0 

January 1997 -- -- --

Pretreatment Compliance Inspection and Audit Manual

For Approval Authorities

July 1986 833-B-86-100 PB90-183625 W277

Pretreatment Compliance Monitoring and Enforcement

Guidance and Software (Version 3.0)

(Manual)

September 1986

(Software)

September 1992 

(Software)

831-F-92-001

(Software)

PB94-118577

(Software)

W269

Procedures Manual for Reviewing a POTW Pretreatment

Program Submission

October 1983 833-B-83-200 PB93-209880 W137

RCRA Information on Hazardous Wastes for Publicly

Owned Treatment Works

September 1985 833-B-85-202 PB92-114396 W351

Report to Congress on the Discharge of Hazardous

Wastes to Publicly Owned Treatment Works

February 1986 530-SW-86-004 PB86-184017 &

PB95-157228

W922 &

W692

Supplemental Manual On the Development And

Implementation of Local Discharge Limitations Under

The Pretreatment Program: Residential and Commercial

Toxic Pollutant Loadings And POTW Removal Efficiency

Estimation

May 1991 21W-4002 PB93-209872 W113
Introduction to the National Pretreatment Program Bibliography

Chapter 8 -53-

OTHER REFERENCE MATERIAL

CERCLA Site Discharges to POTWs CERCLA Site Sampling Program: Detailed Data Report, EPA 540-2-90-008

CERCLA Site Discharges to POTWs Treatability Manual, EPA 540-2-90-007

Considerations of Pollution Prevention in EPA’s Effluent Guideline Development Process, EPA 820-R-95-008

Domestic Septage Regulatory Guidance: A Guide to the EPA 503 Rule, EPA 832-B-92-005

Effluent Guidelines, Leather Tanning, and Pollution Prevention: A Retrospective Study, EPA 820-R-95-006

Environmental Regulations and Technology: The Electroplating Industry, EPA 625/10-80-001

Environmental Regulations and Technology: The Electroplating Industry, EPA/625/10-85/001

EPA'S Whole Effluent Toxicity (WET) Control Policy (Information Sheet and Nonpoint Source Bulletin Board System

Instructions), EPA 833-F-94-005

Everything You Wanted to Know About Environmental Regulations...But Were Afraid to Ask: A Guide for Small

Communities, Region 7 EPA 907-R-92-002

Fact Sheet: Effluent Guidelines: Protecting Our Nation’s Waters from Industrial Discharges, EPA 821-F-93-005

Guidance on Evaluation, Resolution, and Documentation of Analytical Problems Associated with Compliance

Monitoring, EPA 821-B-93-001

Guidance to POTWs for Enforcement of Categorical Standards (Memorandum), November 5, 1984, EPA

Introduction to Water Quality-Based Toxic Control for the NPDES Program, EPA 831-S-92-002

NPDES Basic Permits Writer’s Course Manual, EPA 833-B-97-001 

Plain English Guide to the EPA Part 503 Biosolids Rule, EPA 832-R-93-003

Pretreatment Compliance Monitoring and Enforcement Guidance, September 1986, EPA

Pretreatment Implementation Review Task Force: Final Report to the Administrator, January 30, 1985, EPA

Spill Prevention, Control, and Countermeasure (SPCC) Information Guide, EPA 903-B-93-001

State and Local Government Guide to Environmental Program Funding Alternatives, EPA 841-K-94-001

Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase 1, EPA 600-6-91-005-F

U.S. EPA NPDES Permit Writers’ Manual, EPA-833-B-96-003

User Documentation: POTW Expert, Version 1.1, EPA 625-1-19-000-1

Utility Manager’s Guide to Water and Wastewater Budgeting, EPA 832-B-94-010