6101
United States
Environmental Protection
Agency
Office of Water June 1984
Enforcement and Permits (EN-338) ^ ^
Washington DC 20460 OO "j
_. _
00
S-EPA
IMPDES
Compliance Inspection
Manual
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NPDES COMPLIANCE
INSPECTION MANUAL
Office of Water
Office of Water Enforcement and Permits
June 1984
U.S. Environmental Protection Agency
EH-338
401 M Street S.W.
Washington, D.C. 20460
U^S. Environmental Protection Agency
Regi.n 5, Library (5PL-16)
230 S. Dearborn St -eet, ROOB 1670
Chicago, JL 60604
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON. D.C. 20460
OFFICE OF
WATER
MEMORANDUM
SUBJECT: ( Nj>DES Compliance Inspection Manual
FROM: Rebecca W. Hanmer, Director
Office of Water Enforcement and Permits (EN-338)
TO: Users of the NPDES Compliance Inspection Manual
This manual consolidates and amplifies the inspection
information contained in the various guidance manuals previously
published. Rather than being based on inspection types (i.e.,
compliance evaluation or compliance sampling inspections, etc.),
it is based on compliance inspection activities (i.e., sampling,
flow measurement, etc.). This structure makes the manual a
flexible tool that can be used regardless of changes in inspection
types because the inspector can refer to specific chapters relative
to a particular activity. This flexibility also applies to the
checklists provided at the end of each technical activity chapter.
The inspector's primary objective is to gather information
and report facts. Integral to attaining this objective is a clear
understanding of the purpose of the inspection. This manual will
enable inspectors to focus their efforts properly, thereby
maximizing the effectiveness of inspections and the use of
available resources.
I believe that this manual will provide valuable assistance
to inspectors in the conduct and successful completion of their
very important duties. Please feel free to write the Office of
Water Enforcement and Permits (EN-338) with suggestions, additions
or improvements.
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ACKNOWLEDGEMENTS
We wish to acknowledge the considerable efforts and cooperation of the many
people whose contributions helped in the successful completion of this
document.
This manual was prepared under the direction of Gary Polvi with assistance
from David Rogers and Joseph Dowd, all of the Office of Water Enforcement
and Permits. Extensive reviews were conducted by EPA Headquarters,
Regional Offices and many State agencies. These reviews provided valuable
comments, most of which were incorporated into this manual. Robert Reeves,
EPA Region VI, Charles Sweatt, EPA Region IV, and Joe Kilby of the Delaware
Department of Natural Resources and Environmental Control participated as
peer reviewers and are acknowledged for their important contributions.
This manual was prepared by SRA Technologies, Inc. under EPA Contract No.
68-01-6514.
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DISCLAIMER
This manual has been reviewed by the Office of Water Enforcement and
Permits, U.S. Environmental Protection Agency, and approved for
publication. Mention of trade names or commercial products constitutes
neither endorsement nor recommendation for use.
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Foreword
The National Pollutant Discharge Elimination System (NPDES) Compliance
Inspection Manual has been developed to support inspection personnel in
conducting the field investigations fundamental to the NPDES compliance
program and to provide inspectors with standardized procedures for
conducting complete, accurate inspections.
The depth of coverage of the information presented in this manual will
provide a qualified inspector with the basic guidance necessary to complete
an accurate inspection. The manual presents standard procedures for
inspection; it is assumed the inspector has a working knowledge of
wastewater and related problems, regulations, and control technologies.
The clear, straightforward information presented in the manual will provide
the experienced inspector with sufficient flexibility and easy reference.
New inspection personnel will find support in the orderly and detailed
presentation.
This manual presents the most recent information on NPDES compliance
inspections to date. As new information concerning inspection protocols
and policies emerge, the manual will be revised accordingly. Comments or
changes to the present draft of the manual should be addressed to:
Compliance Branch Chief (EN-338)
Office of Water Enforcement and Permits
U.S. Environmental Protection Agency
401 M Street S.W.
Washington, DC 20460
The information contained in this manual is comprehensive and is designed
to address a wide range of activities. Since each inspection may not
involve all activities, the inspector should use those parts of the Manual
applicable to the particular inspection. This also applies to the
comprehensive checklists at the end of each technical chapter. Although
the manual is written from the point of view of the U.S. Environmental
Protection Agency, the information is applicable to other regulatory
authorities or their authorized representatives.
nspection ManualJune 1984
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Foreword
The manual is organized into eight chapters.
• Chapter One; Introduction describes the NPDES program and
provides general information relating to legal authority and
inspector responsibilities.
• Chapter Two: Inspection Procedures discusses general procedures
common to all NPDES inspections, including pre-inspection
preparation, entry, opening conference, documentation, and closing
conference.
• Chapters Three through Eight provide the specific technical
information necessary to conduct the full range of NPDES compliance
inspection activities. Each chapter describes procedures for the
major technical activities involved in compliance inspections:
- Chapter Three:. Recordkeeping and Reporting
- Chapter Four: Facility Site Review
Chapter Five: Sampling
Chapter Six: Flow Measurement
Chapter Seven: Biomonitoring
- Chapter Eight: Laboratory Quality Assurance
The new NPDES Compliance Inspection Manual consolidates much information
found in previous inspection manuals. Each of the earlier inspection
manuals was based on a particular inspection type and is still accurate.
In some cases, the older manuals cover some technical issues in greater
depth. Those manuals should be retained as technical references, but in
the event of contradictions the new consolidated manual will take
preference.
Inspection Types
The following are descriptions of the different types of inspections that
an NPDES Inspector may conduct at a wastewater facility. At the end of the
descriptions, a table matches minimum inspection activities with inspection
types. Remember that the given activities are only minimum requirements,
and an inspector is not limited to the stated activities.
The inspector should plan all activities with the compliance personnel
prior to inspection. The minimum requirements may serve as a basis for
deciding what activities will be conducted on site and for determining what
additional information is to be gathered or verified during the
inspection. Compliance personnel should choose the type of inspection to
be conducted based on 1) the compliance status of the facility, 2) the
NPDES Inspection Manual ii June 1984
-------
Foreword
information needed from the facility, and 3) the category of facility
involved (e.g., toxic organic effluents, federally funded, etc).
Compliance Evaluation Inspection (CEI)
A CEI is a nonsampling inspection designed to verify permittee compliance
with applicable permit self-monitoring requirements and compliance
schedules. This inspection is based on record reviews and visual
observations and evaluations of the treatment facilities, effluents,
receiving waters, etc. The CEI is used for both chemical and biological
self-monitoring programs. The CEI forms the basis for all other inspection
types except the Reconnaissance Inspection.
Compliance Sampling Inspection (CSI)
During the CSI, representative samples of a permittee's influent and/or
effluent are collected. Samples that are required by the permit are also
obtained. Chemical analyses are then performed and the results are used 1)
to verify the accuracy of the permittee's self-monitoring program and
reports, 2) to determine the quantity and quality of effluents, 3) to
develop permits, and 4) where appropriate, as evidence for enforcement
proceedings. In addition, a CSI includes the same objectives and tasks as
a CEI.
Performance Audit Inspection (PAI)
The PAI is used to evaluate the permittee's self-monitoring program. As
with a CEI, the PAI is used to verify the permittee's reported data and
compliance through a check of the records. In a CEI, the inspector carries
out a cursory visual observation of the treatment facilities, effluents and
receiving waters. In a PAI, the inspector actually observes the permittee
going through all of the steps in the self-monitoring process from sample
collection and flow measurement, through lab analyses, data workup and
reporting. Also, the PAI inspector may leave a check sample for the
permittee to analyze. The PAI is more resource intensive than a CEI, but
less than a CSI because sample collection and analyses by EPA or the State
are not included.
Compliance Biomonitoring Inspection (CBI)
A CBI evaluates the biological effect of a permittee's effluent
discharge(s) on test organisms through the utilization of acute toxicity
bioassay techniques. In addition, this inspection includes the same
objectives and tasks as CEI.
Toxics Sampling Inspection (XSI)
The XSI has the same objectives as a conventional CSI, however, it places
increased emphasis on toxic substances (i.e. the priority pollutants) other
NPDES Inspection Manual iii June 1984
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Foreword
than heavy metals, phenols and cyanide, which are typically included in a
CSI. Increased resources over a CSI are needed because highly
sophisticated techniques are used to sample and analyze the samples for
toxic pollutants.
Diagnostic Inspection (PI)
The DI focuses primarily on municipal POTW's that have received Federal
construction grants but are not in compliance with permit requirements.
The DI is designed to assist smaller POTW's that do not have a
self-diagnostic capability. The emphasis of the DI is to identify
compliance problems and to direct them to the permittee for correction.
Reconnaissance Inspection (RI)
The RI is used to obtain a preliminary overview of a permittee's compliance
program. The inspector performs a brief visual inspection of the
permittee's treatment facility, effluents and receiving waters. The RI
utilizes the inspector's experience and judgment to quickly summarize a
permittee's compliance program. The objective of the RI is to expand
inspection coverage without increasing inspection resources. It is the
briefest of all NPDES inspections.
Legal Support Inspection (LSI)
The LSI is a resource intensive inspection conducted when an enforcement
problem is identified as a result of a routine inspection or a complaint.
For an LSI, the appropriate resources are assembled to effectively deal
with a specific enforcement problem.
NPDES Inspection Manual iv June 1984
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COMPARISON OF INSPECTION ACTIVITIES WITH INSPECTION TYPES
INSPECTION TYPES
ACTIVITY/LOCATION IN MANUAL
Meeting with Compliance Personnel
Compliance File Review
(Chapter 2, Section 1)
Entry
(Chapter 2, Section 2)
Opening Conference
(Chapter 2, Section 3)
Outfall/Receiving Waters Review
(Chapter 4)
Facility Site Review
(Chapter 4)
Compliance Schedule Verification
(Pg. 3-4)
Laboratory Review
(Chapter 8)
Quality Assurance Verification
(Chapter 8)
Record Keeping/Datahandling Verification
(Chapter 3)
Sampling and Analysis
(Chapter 5, Section 2)
Inspect Flow Measurement Equipment
(Chapter 6)
Sampling Techniques Verification
(Chapter 5, Section 1)
Analysis Techniques Verification
(Pg. 8-2)
Leave a QA Sample
Biomonitoring Verification
(Chapter 7, Section 1)
Conduct Bioassay
(Chapter 7, Section 2)
Closing Conference
(Chapter 2, Section 5)
Inspection Documentation
(Chapter 2, Section 4)
CEI
C
C
C
C
C
C
C
C
C
C
C
C
CSI
C
C
C
C
C
C
C
C
C
C
C
C
C
TOX
C
C
C
C
C
C
C
C
C
I
C
C
C
BIO
C
1
1
I
C
C
C
C
C
2
2
1
C
C
PAI
C
C
I
C
C
C
I
I
I
I
I
0
I
C
RI
C
C
C
C
C
C
C
C
C
C
DIAG
I
C
I
I
I
C
I
I
I
0
I
C
C
I
I
LEGEND
I = Activity is conducted in depth (detailed)
C = Activity is conducted in a cursory fashion (brief)
0 = Activity is optional
1. Activity is completed in either an in depth fashion or a cursory
fashion depending on whether inspection is a flow-through bioassay
or a static bioassay respectively.
2. Activity is completed during a flow through bioassay but is not
completed during a static bioassay.
NPDES Inspection Manual
June 1984
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NFDES Inspection Manual vi June 1984
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Table of Contents
Contents Page
Chapter One: Introduction 1-i
Chapter Two; Inspection Procedures 2-i
Pre-Inspection Preparation 2-1
Entry 2-9
Opening Conference 2-13
Documentation 2-15
Closing Conference 2-25
Inspection Report 2-27
Chapter Three; Recordkeeping and Reporting 3-i
Chapter Four: Facility Site Review 4-1
Chapter Five: Sampling 5-i
Evaluation of Permittee Sampling Program 5-1
Inspector's Compliance Sampling 5-7
Chapter Six; Flow Measurement 6-i
Evaluation of Permittee's Flow Measurement 6-1
Flow Measurement Compliance 6-5
Supplementary Information 6-11
Chapter Seven: Biomonitoring 7-1
Evaluation of Permittee Self-Biomonitoring Program 7-1
Compliance Biomonitoring Inspection 7-19
Chapter Eight; Laboratory Quality Assurance 8-i
NPDES Inspection Manual vii June 1984
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Chapter One
Introduction
Contents Page
Legal Authority for NPDES Inspections 1-1
Inspection Authority 1-1
State Program Authority 1-1
Responsibilities of the NPDES Inspector 1-2
Legal Responsibilities 1-2
Procedural Responsibilities 1-2
Safety Responsibilities 1-3
Professional Responsibilities 1-3
Quality Assurance Responsibilities 1-4
List of Tables
1-1 Inspector Responsibilities in the Inspection Process 1-6
NPDES Inspection Manual 1-i June 1984
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Chapter One
Introduction
Legal Authority for NPDES Inspections
The Federal Water Pollution Control Act of 1972, as amended by the Clean
Water Act of 1977, gives the Environmental Protection Agency (EPA) the
authority to regulate the discharge of pollutants to waters of the United
States. The Act provides broadly defined authority to establish the
National Pollutant Discharge Elimination System (NPDES) Permit Program, to
define control technologies, to establish effluent limitations, to obtain
information through reporting and compliance inspections, and to take
enforcement actions (both civil and criminal) when violations of the Act
are found.
Inspection Authority
Dischargers of pollutants are issued permits under Section 402 that set
specific limits and operating conditions to be met by the permittee.
Section 308 authorizes inspections and monitoring to determine whether or
not NPDES permit conditions are being met. The section provides for two
types of monitoring:
• Self-monitoring, where the facility must monitor itself; and
• EPA monitoring, which may consist of checking the self-monitoring
or conducting monitoring of its own.
According to the Act, EPA may conduct an inspection wherever there is an
existing NPDES permit, or where a discharge exists or is likely to exist
and no permit has been issued.
State Program Authority
Much of the compliance monitoring in the NPDES program takes place at the
State level. Sections 308 and 402 of the Act provide for the transfer of
Federal program authority to the States to conduct NPDES permit compliance
monitoring. EPA Regional Administrators and some State water pollution
control agencies have signed formal cooperative agreements that ensure
timely, accurate monitoring of compliance with permit conditions.
NPDES Inspection Manual 1-1 June 1984
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Chapter One Introduction
Responsibilities of the NPDES Inspector
The primary role of an NPDES inspector is to gather information that
can be used to determine compliance with permit conditions, applicable
regulations, and other requirements. The NPDES inspector also plays an
important role in enforcement case development and support, and in permit
development. To fulfill these roles, inspectors are required to know and
abide by legal requirements concerning inspections, procedures for
effective inspection and evidence collection, accepted safety practices,
and quality assurance standards.
Legal Responsibilities
It is essential that inspectors conduct all inspection activities within
the legal framework established by the Act, including:
• Presenting proper credentials;
• Presenting required notices and receipts; and
• Properly handling confidential business information.
It is also important that inspectors be familiar with the conditions of the
specific permit and with all applicable statutes and regulations.
Procedural Responsibilities
Inspectors must be familiar with general inspection procedures and evidence
collection techniques to ensure accurate inspections and avoid endangering
potential legal proceedings on procedural grounds.
• Inspection Procedures. Inspectors should observe standard
procedures for conducting each inspection element.
Responsibilities are illustrated in Table 1-1.
• Evidence Collection. Inspectors must be familiar with general
evidence gathering techniques. Because the government's case in a
civil or criminal prosecution depends on the evidence gathered by
the inspector, it is imperative that each inspector keep detailed
records of each inspection. These data will serve as an aid in
preparing the inspection report, in determining the appropriate
enforcement response, and in giving testimony in an enforcement
case.
In particular, inspectors must know how to:
• Substantiate facts with items of evidence, including samples,
photographs, document copies, statements from witnesses, and
personal observations.
NPDES Inspection Manual 1-2 June 1984
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Chapter One Introduction
• Evaluate what evidence Is necessary (routine inspections);
• Know chain-of-custody procedures;
• Collect and preserve evidence in a manner that will be
incontestable in legal proceedings;
• Write clear, objective, and informative inspection reports; and
• Testify in court and administrative hearings.
Safety Responsibilities
The inspection of wastewater and other environmental pollution control
facilities always poses a certain degree of risk. To avoid unnecessary
health and safety risks, the inspector should be familiar with all safety
guidance and practices and should:
• Use safety equipment in accordance with guidance received and
labeling instructions;
• Maintain safety equipment in good condition and proper working
order;
• Dress appropriately for the particular activity, and wear
appropriate protective clothing; and
• Use any safety equipment customary in the establishment being
inspected (e.g., hard hat or safety glasses).
If there are any safety related questions, consult the current approved
safety manual.
Professional Responsibilities
Inspectors are expected to perform their duties with the highest degree of
professionalism. Procedures and requirements ensuring ethical actions have
been established through many years of government inspection experience.
These procedures and standards of conduct have evolved for the protection
of the individual and the Agency, as well as industry, so that the rights
of all parties are protected.
• All investigations are to be conducted within the framework of the
United States Constitution and with due regard for individual
rights regardless of race, sex, creed, or national origin.
• Inspectors are to conduct themselves at all times in accordance
with the regulations prescribing employee responsibilities and
conduct.
NPDES Inspection Manual 1-3 June 1984
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Chapter One Introduction
• The facts of an investigation are to be developed and reported
completely, accurately, and objectively.
• In the course of an investigation, any act or failure to act
motivated by reason of private gain is illegal. Actions which
could be construed as such should be scrupulously avoided.
• A continuing effort to improve professional knowledge and technical
skill in the investigative field should be made.
Professional Attitude. The inspector is a representative of EPA and is
often the initial or only contact between the Agency and the permittees.
In dealing with facility representatives and employees, inspectors must be
dignified, tactful, courteous, and diplomatic. A firm but responsive
attitude will help to establish an atmosphere of cooperation and will
initiate good working relations. Inspectors should not speak of any
product, manufacturer, or person in a derogatory manner.
Attire. Inspectors should dress appropriately, including wearing
protective clothing or equipment, for the activity in which they are
engaged.
Gifts, Favors, Luncheons. Inspectors should not accept favors or benefits
under circumstances that might be construed as influencing the performance
of governmental duties. EPA regulations provide an exemption whereby an
inspector could accept food and refreshment of nominal value on infrequent
occasions in the ordinary course of a luncheon or dinner meeting or other
meeting, or during an inspection tour. Inspectors should use this
exemption only when absolutely necessary.
Requests for Information. EPA has an "open-door" policy on releasing
information to the public. This policy aims at making information about
EPA and its work freely and equally available to all interested
individuals, groups, and organizations. In fact, EPA employees have both a
legal and traditional responsibility for making useful educational and
safety information available to the public. This policy, however, does not
extend to information relating to the suspicion of a violation, evidence of
possible misconduct, or confidential business information.
Quality Assurance Responsibilities
The inspector must assume primary responsibility for ensuring the quality
of compliance inspection data. While other organizational elements play an
important role in quality assurance, it is the inspector who must ensure
that all data introduced into an inspection file are complete, accurate,
and representative of existing conditions. To help the inspector meet
these responsibilities, Regional Offices have established quality assurance
plans that identify individual responsibilities and document detailed
procedures.
NPDES Inspection ManualF^June 1984
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Chapter One Introduction
The objective of a quality assurance plan is to establish standards that
will guarantee that inspection data meet the requirements of all users.
Many elements of quality assurance plans are incorporated directly into the
basic inspection procedures and may not be specifically identified as
quality assurance techniques.
The inspector must be aware that following established inspection
procedures is critical to the inspection program. These procedures have
been developed to reflect the following quality assurance elements:
• Valid data collection;
• Approved, standard methods;
• Control of service, equipment, supplies;
• Quality analytical techniques; and
• Standard data handling and reporting.
HPDES Inspection Manual 1-5 June 1984
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Chapter One Introduction
Table 1-1
Inspector Responsibilities in the Inspection Process
The elements of the Inspection process listed below are common to most
NPDES compliance inspections. While the emphasis given to each element
may vary with each facility, the Inspector's procedural responsibilities
remain as listed.
1. Pre-Inspection Preparation; Ensure effective use of inspection
resources.
Establish purpose and scope of inspection.
Review background information and Agency records.
Develop plan for inspection.
Prepare documents and equipment.
Coordinate schedule with laboratory if samples are to be collected.
Coordinate schedule with other appropriate regulatory authority.
2. Entry; Establish legal entry to facility.
• Present official credentials.
• Manage denial of entry if necessary.
3. Opening Conference; Orient facility officials to inspection plan.
• Discuss inspection objectives and scope.
• Establish working relationship with facility officials.
4. Facility Inspection: Determine compliance with permit conditions;
collect evidence of violations.
Conduct visual inspection of facility.
Review facility records.
Inspect monitoring equipment and operations.
Collect samples.
Prepare documentation of inspection activities.
5. Closing Conference: Conclude inspection.
• Collect missing or additional information.
• Clarify questions with facility officials.
• Prepare necessary receipts.
• Review inspection findings and inform officials of follow-up
procedures.
• Issue deficiency notice if appropriate.
6. Inspection Report; Organize inspection findings into a useful,
objective evidence package.
• Complete NPDES Compliance Inspection Report form.
• Prepare narrative report, if appropriate.
NPDES Inspection Manual 1-6 June 1984
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Chapter Two
Inspection Procedures
Contents
1 Pre-Inspection Preparation
Review of Facility Background 2-1
Sources of Facility Background Information 2-3
Development of an Inspection Plan 2-6
Notification of the Facility 2-6
State Notification of Federal Inspection 2-7
Equipment Preparation 2-7
2 Entry
Entry Procedures 2-9
Authority 2-9
Arrival 2-9
Credentials 2-9
Consent 2-10
Waivers, Releases, and Sign-In Logs 2-10
Problems with Entry or Consent 2-11
Denial of Entry 2-11
Important Considerations 2-11
Withdrawal of Consent During Inspection 2-12
Denial of Access to Some Areas of the Facility 2-12
Warrants 2-12
3 Opening Conference
Considerations 2-13
NPbfiS Inspection Manual " ^i ~ June 1984
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Chapter Two Contents
4 Documentation
Inspector's Field Notebook 2-15
Inspection Entries 2-15
Samples 2-16
Statements 2-16
Procedures and Considerations 2-17
Photographs 2-18
Equipment 2-18
Scale, Location, and Direction 2-18
Safety 2-19
Documenting Photographs 2-19
Drawings and Maps 2-19
Printed Matter 2-20
Mechanical Recordings 2-20
Copies of Records 2-20
Identification Procedures 2-21
General Consideration 2-22
Routine Records 2-22
Confidential Information 2-22
Disclosure of Official Information 2-22
Trade Secrets and Confidential Information 2-22
Handling Confidential Information 2-23
5 Closing Conference
Precautions and Guidelines 2-25
Deficiency Notice 2-25
6 Inspection Report
Objective of the NPDES Inspection Report 2-27
Elements of a Report 2-28
NPDES Compliance Inspection Report Form 2-28
Supplementary Narrative Information 2-28
Copies of Completed Checklists 2-30
Documentary Support 2-30
The Permit Compliance System (PCS) 2-30
List of Tables
2-1 NPDES Related Statutes and Regulations 2-5
List of Figures
2-1 Sample 308 Letter 2-8
NPDES Inspection Manual 2-ii June 1984
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Chapter Two
1 Pre-lnspection Preparation
Preplanning Is necessary to ensure that the inspection is properly focused
and is conducted smoothly and efficiently. This planning involves:
• Review of facility background;
• Development of an inspection plan; and
• Notification of the facility.
Review of Facility Background
Collection and analysis of available background information on the candi-
date facility is essential to the effective planning and overall success of
a compliance inspection. Materials obtained from files of Federal, State,
and local agencies, technical libraries, and other information sources will
enable inspectors to become familiar with facility operations; conduct the
inspection in a timely manner; minimize inconvenience to the facility by
not requesting data previously provided to the Federal, State, and/or local
agencies; conduct a thorough and efficient inspection; clarify technical
and legal issues before entry; and develop a sound and factual inspection
report. The types of information that may be available for review are
listed below. The inspector must determine the amount of background infor-
mation necessary to perform the inspection.
• General Facility Information
- Maps showing facility location, wastewater discharge pipes, and
and geographic features.
- Names, titles, and phone numbers of responsible facility
officials.
MPDES Inspection Manual 2-1 June 1984
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Chapter Two Pre-Inspection Preparation
— Any special entry requirements.
- Nature of processing operation and wastewater.
- Production levels, past, present, and future.
- Hydrological data.
- Geology/hydrogeology of the area.
- Changes in facility conditions since previous inspection/
permit application.
- Available aerial photographs.
• Requirements, Regulations, and Limitations
- Copies of existing permits, regulations, and requirements—
Federal, State, and local—and restrictions placed on dis-
charges, compliance schedules, monitoring and reporting
requirements, available monitoring stations, and analytical
methods used by the facility.
- Special exemptions and waivers, if any.
- Receiving stream water quality standards.
- Previous facility applications for water, air, and solid
waste permits. These files may contain useful data not shown
elsewhere.
- Grant applications for publicly owned treatment works, R&D
demonstration projects, and progress reports on these pro-
jects.
• Facility Compliance and Enforcement History
- Federal and State compliance files.
- Correspondence among facility, local, State, and Federal
agencies.
- Complaints and reports, follow-up studies, findings, remedial
action.
- Previous inspection reports, records, correspondence on past
incidents of violations, exceedences, status of requested
regulatory corrective action, if any, and compliance by
facility.
- Status of current and pending litigation against facility.
NPDES Inspection Manual 2-2 June 1984
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Chapter Two Pre-Inspection Preparation
- Self-monitoring data and reports.
- Previous EPA, State, and consultant studies and reports.
- Previous deficiency notices issued to facility.
- Laboratory capabilities.
• Pollution Control and Treatment Systems
- Description and design data for pollution control system and
process operation.
- Sources and characterization of discharge.
- Type and amount of waste discharged.
- Spill contingency plans.
- Available by-passes or diversions and spill containment
facilities.
- Pollution control, treatment methods, and monitoring systems.
• Pretreatment Information
- Information concerning Pretreatment Program Compliance Schedule.
- POTW's annual pretreatment report.
- Information concerning industrial user's such as:
o User charge
o Waste load
o Type of waste
o Compliance
Sources of Facility Background Information
• Laws and Regulations - The Clean Water Act and related regula-
tions establish procedures, controls, and other requirements ap-
plicable to a facility. In addition, State laws and regulations,
and sometimes even local ordinances, are applicable to the same
facility. (See Table 2-1 for applicable NPDES statutes and regu-
lations. )
• Permits and Permit Applications - Permits provide information on
the limitations, requirements, and restrictions applicable to dis-
charges; compliance schedules; and monitoring, analytical, and
reporting requirements. Applications provide technical
NPDES Inspection Manual 2-3 June 1984
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Chapter Two Pre-Inspection Preparation
information on facility size, layout, and location of pollutant
sources; treatment and control practices; contingency plans and
emergency procedures; and pollutant characterization—types,
amounts, and points/locations of discharge.
• Regional and State Files and Contacts - Files or contacts often can
provide facility self-monitoring data, inspection reports, and
permits and permit applications applicable to individual
facilities. They can provide compliance, enforcement, and
litigation history; special exemptions and waivers applied for and
granted or denied; citizen complaints and action taken; process
operational problems/solutions; pollution problems/solutions;
laboratory capabilities or inabilities; and other proposed or
historical remedial actions. Consultant reports can provide design
and operation data and recommendations for processes, pollutant
sources, treatment/control systems, and remedial measures.
• Technical Reports, Documents, and References - These information
sources provide generic information on industrial process opera-
tions, as well as pertinent specific data on available treatment/
control techniques, such as their advantages or drawbacks, and
limits of application. Such sources include Effluent Guideline and
New Source Performance Standard development documents. Other im-
portant information from these sources includes waste characteriza-
tion and loads from industrial processes and removal efficiencies
for exemplary treatment systems.
• Other Statutory Requirements - Facility files maintained pursuant
to other statutes (e.g. TSCA, RCRA, CERCLA, FIFRA, Clean Air Act,
etc.) also contain information useful to the NPDES inspection.
NPDES Inspection Manual 2^ June 1984
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Chapter Two
Pre-Inspection Preparation
Table 2-1
HPDES Related Statutes and Regulations
Topic
Reference
Inspection Authority
Self-Monitoring and
Recordkeeping Authority
Confidential Information
Emergency Authority
Employee Protection
Permits
EPA Permitting Procedures
Technical Requirements
Best Management Practices (BMP)
Spill Prevention Control and Counter-
measure Plan (SPCC)
Waivers
Effluent Guidelines
Pretreatment Standards
CWA1
§308
§308
§308(b)
§504
§507
§402
§304(e)
§311
§301
§304
40 CFR2
122.41(i)a,
123.26a
122.41(h), (j),
and (l)a, 122.48a
2.201, 2.215,
2.302, 122.7b
123.27a
122b, 123.25a
124
129a, 133a, 136a
125
112
125, 230
400-460a
§307, 402 125,403 and 400-
460a
Clean Water Act
2 Code of Federal Regulations, Revised as of July 1, 1983
aApplies to State Programs
t>Partially applies to State Programs
NPDES Inspection Manual
June 1984
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Chapter Two Pre-Inspection Preparation
Development of an Inspection Plan
A plan is recommended for the effective conduct of a compliance inspec-
tion. After reviewing the available background information, a comprehen-
sive plan is prepared to define inspection objectives, the tasks required
to fulfill the objectives, the inspection schedule, and when findings and
conclusions on the work will be reported. A project plan generally addres-
ses the following items:
• Objectives
- What is the purpose of the inspection?
- What is to be accomplished?
• Tasks
- What tasks are to be completed?
- What information must be collected?
• Procedures
- What procedures are to be used?
- Will the inspection require special procedures?
• Resources
- What personnel will be required?
- What equipment will be required?
• Schedule
- What will be the time requirements and order of inspection
activities?
- What will be the milestones?
• Coordination
- What coordination with laboratories or other regulatory agen-
cies is required?
Notification of the Facility
In the NPDES program, the permittee is sometimes notified by a "308 Letter"
that the facility is scheduled for an inspection. The 308 Letter advises
the permittee that an inspection is imminent, and usually requests informa-
tion regarding on-site safety regulations to avoid problems concerning
safety equipment at the time of the inspection. The 308 Letter may also
specify the exact date of the inspection if coordination with the permittee
HPDES Inspection Manual 2-6 ~ June 1984
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Chapter Two Pre-Inspection Preparation
is required. It is also used to inform the permittee of the right to as-
sert a claim of confidentiality. (Figure 2-1 is an example of a typical
308 Letter.) Depending on the type of inspection, the permittee may also
be notified by telephone that an inspection is imminent.
Notification is not recommended when illegal discharges or emissions or im-
proper records are suspected. The concern that physical conditions may be
altered prior to the inspection or that records will be destroyed
justifies an unannounced inspection. A written notification could then be
presented at the time of the unannounced inspection.
State Notification of Federal Inspection
The inspector must be sure that the appropriate State regulatory agency is
notified in a timely manner of inspections to be conducted within their
jurisdictions. The State should be notified of all Federal inspections
unless there are exceptional circumstances where disclosing inspection
information would jeopardize an unannounced inspection.
Equipment Preparation
Part of the pre-inspection process involves obtaining and preparing inspec-
tion equipment. The type of equipment may vary according to the facility
inspected and the type of inspection. All equipment must be checked, cali-
brated, and tested before use. The inspector must also ensure that all
materials necessary to complete an inspection are taken to the inspection
site. The inspector is responsible for maintaining the equipment properly
in accordance with operating instructions.
Safety equipment and procedures required for. a facility will be based on
the response to the notification or 308 Letter and standard safety proce-
dures. Safety requirements must be met, not only for safety reasons but to
ensure that the inspector is not denied entry to the facility or parts of
it.
Photocopies of appropriate checklists should be obtained during the pre-
inspection preparation.
NPDES Inspection Manual 2^7 June 1984
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Chapter Two Pre-Inspection Preparation
Figure 2-1
Sanple 308 Letter
Certified Mail - Return Receipt Requested
Date
Dear Sir:
Pursuant to the authority contained in Section 308 of the Clean Water
Act (33 U.S.C. 1251 et seq.), representatives of the U.S.
Environmental Protection Agency (EPA), or a contractor retained by
EPA, shall conduct, within the next year, a compliance monitoring
inspection of your operations including associated waste treatment
and/or discharge facilities located at (site of inspection). This
inspection will ascertain the degree of compliance with the
requirements of the National Pollutant Discharge Elimination System
(NPDES) permit issued to your organization.
Our representatives may observe your process operations, inspect your
monitoring and laboratory equipment and methods, collect samples,
examine appropriate records, and will be concerned with related
matters.
In order to facilitate easy access to the plant site, please provide
the name of the responsible facility official that can be contacted
upon arrival at the plant. Additionally, we would appreciate receiv-
ing a list of the safety equipment you would recommend that our repre-
sentatives have in their possession in order to safely enter and con-
duct the inspection. Please provide the information requested within
14 days of receipt of this letter.
If you have any questions relating to anything concerning this
inspection, please call (appropriate designated official).
Sincerely yours,
Director
Water Management Division
NPDES Inspection Manual 2r8 June 1984
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Chapter Two
2 Entry
Entry Procedures
Authority
§308(a)(4)(B) of the Clean Water Act states:
"... the Administrator or his authorized representa-
tive, upon presentation of his credentials shall have a
right of entry to, upon, or through any premises in
which an effluent source is located or in which any re-
cords required to be maintained. . . and may at reason-
able times have access to and copy any records, inspect
any monitoring equipment or method. . . and sample any
effluents which the owner or operator of such source is
required to sample. . ."
Arrival
Arrival at the facility should be during normal working hours. The facil-
ity owner or agent in charge should be located as soon as the inspector
arrives on the premises.
Credentials
When the proper facility officials have been located, the inspector should
introduce himself or herself as an EPA/State inspector and present the
proper EPA credentials. These credentials indicate that the holder is a
lawful representative of the regulatory agency and is authorized to perform
NPDES inspections. The credentials must be presented whether or not iden-
tification is requested.
NPDES Inspection Manual2^9June 1984
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Chapter Two Entry
After facility officials have scrutinized the credentials, they may tele-
phone the appropriate State or EPA Regional Office for verification of the
inspector's identification.
Credentials should never leave the sight of the inspector.
Consent
Consent to inspect the premises must be given by the owner or operator at
the time of the inspection. As long as the inspector is allowed to enter,
entry is considered voluntary and consensual, unless the inspector is ex-
pressly told to leave the premises. Express consent is not necessary; ab-
sence of an express denial constitutes consent.
Reluctance To Give Consent. The receptiveness of facility officials to-
ward inspectors is likely to vary from facility to facility. Most inspec-
tions will proceed without difficulty. If consent to enter is flatly
denied, the inspector should follow Denial of Entry procedures. In other
cases, officials may be reluctant to give entry consent because of mis-
understandings of responsibilities, inconvenience to a firm's schedule, or
other reasons that may be overcome by diplomacy and discussion.
Whenever there is difficulty in gaining consent to enter, inspectors
should tactfully probe the reasons and work with officials to overcome the
obstacles. Care should be taken, however, to avoid threats of any kind,
inflammatory discussions, or deepening of misunderstandings. If the situa-
tion is beyond the authority or ability of the inspector, the regulatory
office should be contacted for guidance.
Uncredentialed Persons Accompanying an Inspector. The consent of the
owner or agent in charge must be obtained for the entry of persons accom-
panying an inspector to a site if they do not have specific authorization.
If consent is not given voluntarily, these persons may not enter the
premises. If consent is given, these persons may not view confidential
business information unless officially authorized for access.
Waivers, Releases, and Sign-In Logs
When the facility provides a blank sign-in sheet, log, or visitor register,
it is acceptable for inspectors to sign it. Note however that EPA em-
ployees will not sign any type of "waiver" or "visitor release" that would
relieve the facility of responsibility for injury or which would limit the
rights of the Agency to use data obtained from the facility. The inspector
must not agree to any such unwarranted restrictive conditions.
If such a waiver or release is presented, the inspectors should politely
explain they cannot sign and request a blank sign-in sheet. If the inspec-
tors are refused entry because they do not sign such release, they should
leave and immediately report all pertinent facts to the appropriate super-
visory and/or legal staff. All events surrounding the refused entry should
NPDES Inspection Manual 2-10 June 1984
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Chapter Two Entry
be fully documented. Problems should be discussed cordially and profes-
sionally. Facility officials must not be subjected to intimidation by the
Federal/State government's right to inspect.
Problems with Entry or Consent
Because inspections may be considered adversary proceedings, inspectors
may be challenged as to their legal authority, techniques, and compe-
tency. Facility officials may also display antagonism to Agency person-
nel. In all cases, the inspectors must cordially explain the authorities
and the reasons for the protocols followed. If explanations are not satis-
factory or disagreements are irresolvable, the inspectors should leave and
obtain further direction from the appropriate Agency supervisory or legal
staff. Professionalism and politeness must prevail at all times.
Denial of Entry
If an inspector is refused entry into a facility for the purpose of an in-
spection under the Clean Water Act (CWA), certain procedural steps must be
followed. The procedures have been developed in accordance with the 1978
U.S. Supreme Court decision in Marshal v. Barlow's, Inc.
1. Make certain that all credentials and notices have been properly
presented to the facility owner or agent in charge.
2. If entry is not granted, ask why. Tactfully probe the reason for
the denial to see if obstacles (such as misunderstandings) can be
cleared. If resolution is beyond the authority of the inspector,
he or she may suggest that the officials seek advice from their at-
torneys on clarification of the scope of EPA's inspection authority
under Section 308 of the CWA.
3. If entry is still denied, the inspector should withdraw from the
premises and contact his or her supervisor. The supervisor will
confer with attorneys to discuss the desirability of obtaining an
administrative warrant.
4. All observations pertaining to the denial are to be carefully noted
in the field notebook. Include facility name and exact address,
name and title of person(s) approached, authority of person(s) who
refused entry, date and time of denial, detailed reasons for
denial, facility appearance, any reasonable suspicions that refusal
was based on a desire to cover up regulatory violations, etc. All
such information will be important should a warrant be sought.
Important Considerations
- Under no circumstances should the inspector discuss potential
penalties or do anything that may be construed as coercive or
threatening.
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Chapter Two Entry
- Inspectors should use discretion and avoid any situations that may
be potentially threatening or inflammatory. In the event of a
threatening confrontation, the inspector should document the event
and report it immediately to the staff attorney. If feasible,
statements from witnesses should be obtained and included in the
documentation.
Withdrawal of Consent During Inspection
If the agent-in-charge asks the inspector to leave the premises after the
inspection has begun, the inspector should leave as soon as possible,
following the procedures above for denial of entry. All activities and
evidence obtained prior to the withdrawal of consent are valid. The in-
spector should ensure that all personal and government equipment is removed
from the facility.
Denial of Access to Some Areas of the Facility
If, during the course of the inspection, access to some parts of the facil-
ity is denied, the inspector should make a notation of the circumstances
surrounding the denial of access and of the portion of the inspection that
could not be completed. He or she should then proceed with the rest of the
inspection. After leaving the facility, the inspector should contact the
Regional Office to determine whether a warrant should be obtained to
complete the inspection.
Warrants
The inspectors may be instructed by Agency attorneys, under certain circum-
stances, to conduct an inspection under search warrant. A warrant is a
judicial authorization for appropriate persons to enter specifically
described locations and to perform specific Inspection functions. It is
possible that a pre-inspection warrant could be obtained where there is
reason to believe that entry will be denied when the inspector arrives at
the facility or when the Inspector anticipates violations that could be
hidden during the time required to obtain a search warrant.
NPDES Inspection Manual 2-12 June 1984
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Chapter Two
3 Opening Conference
Once credentials have been presented and legal entry has been established,
the inspector can proceed to outline inspection plans with facility offi-
cials. At the opening conference, the inspector provides names of the in-
spectors, purpose of the inspection, authorities under which the inspection
is being conducted, and procedures to be followed. The Agency encourages
cooperation between the inspectors and the facility officials; this will
facilitate assignments and contribute to the success of the inspection.
Considerations
Inspection Objectives. An outline of inspection objectives will
inform facility officials of the purpose and scope of the inspec-
tion and may help avoid misunderstandings.
Order of Inspection. A discussion of the order in which the in-
spection will be conducted will help eliminate wasted time by al-
lowing officials time to make records available and start up inter-
mittent operations.
Meeting Schedules. A schedule of meetings with key personnel will
allow them to allocate a clear time to spend with the inspector.
List of Records. A list of records to be inspected will allow of-
ficials to gather and make them available for the inspector.
Accompaniment. It is important that a facility official accompany
the inspector during the inspection not only to answer questions
and to describe the plant and its principal operating
characteristics, but also for safety and liability considerations.
MPDES Inspection Manual 2-13 June 1984
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Chapter Two Opening Conference
• Permit Verification. The inspector should verify the following
information from facility officials:
- Correct name and address of facility;
- Correct name and location of receiving waters;
- Number and location of discharge points; and
- Principal product(s) and production rates where specifically
requested.
• Safety Requirements. The inspector should determine what OSHA and
facility safety regulations will be involved in the inspection, and
should be prepared to meet these requirements.
• Closing Conference. A post-inspection meeting should be scheduled
with appropriate officials to provide a final opportunity to gather
information, answer questions, present findings and deficiencies,
and complete administrative duties.
• New Requirements. The inspector should discuss any new rules and
regulations that might affect the facility and answer questions
pertaining to them. If the inspector is aware of proposed rules
that might affect the facility, he or she may wish to encourage
facility officials to obtain a copy.
• Split Samples. Facility officials should be informed during the
opening conference of their right to receive a split of any physi-
cal sample collected for laboratory analysis. Officials should
indicate at this point the desire to receive split samples so that
arrangements can be made to secure the samples during the inspec-
tion.
• Photographs. Photographs can be used to prepare a more thorough
and accurate inspection report, as evidence in enforcement pro-
ceedings, and to better explain conditions found at the plant.
The facility, however, may object to the use of cameras on their
property. If a mutually acceptable solution cannot be reached and
photographs are considered essential to the inspection, Agency
supervisory and legal staff should be contacted for advice.
Facility personnel may also request that any photographs taken
during the visitation be considered confidential. The Agency is
obliged to comply with this request pending further legal deter-
mination. Self-developing film, although of lower quality, is
useful in certain situations. A facility may refuse permission to
take photographs unless they can see the finished print. Duplicate
photographs (one for the inspector and the other for the company)
should satisfy this need.
HPDES Inspection Manual2-14June 1984
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Chapter Two
4 Documentation
Providing strong documentary support of discrepancies uncovered in an in-
spection is a basic responsibility of an inspector. Documentation serves
to "freeze" the actual conditions existing at the time of the inspection so
that evidence may be examined objectively at a later date by compliance
personnel.
Documentation is a general term referring to all print and mechanical media
produced, copied, or taken by an Inspector to provide evidence of suspected
violations. Types of documentation include the field notebook, statements,
photographs, drawings and maps, printed matter, mechanical recordings, and
copies of records.
Inspector's Field Notebook
The core of all documentation relating to an inspection is the field note-
book, which provides accurate and inclusive documentation of all inspection
activities. The notebook will form the basis for written reports and
should contain only facts and pertinent observations.
Language should be objective, factual, and free of personal feelings or
terminology that might prove inappropriate. Notebooks become an important
part of the evidence package and can be entered in court as evidentiary
material.
Inspection Entries
Since an inspector may be called to testify in an enforcement proceeding,
it is imperative that each inspector keep detailed records of inspections,
investigations, samples collected, and related inspection functions. Types
of information that should be entered into the field notebook include:
NPDES Inspection Manual 2=13June 1984
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Chapter Two Documentation
• Observations. All conditions, practices, and other observations
that will be useful in preparing the inspection report or that
will validate evidence should be recorded.
• Documents and Photographs. All documents taken or prepared by the
inspector should be noted and related to specific inspection
activities. (Photographs taken at a sampling site should be
listed, and described.)
• Unusual Conditions and Problems. Unusual conditions and problems
should be noted and described in detail.
• General Information. Names and titles of facility personnel and
the activities they perform should be listed along with statements
they may have made and other general information. Weather condi-
tion should be recorded. Information about a facility's record-
keeping procedures may be useful in later inspections.
The field notebook is a part of the Agency's files and is not to be con-
sidered the inspector's personal record. Notebooks are held indefinitely
pending disposition instructions.
Samples
Samples are the evidence most frequently gathered by inspectors. For the
analysis of a sample to be admissible as evidence, a logical and documented
connection must be shown between samples taken and analytical results re-
ported. This connection is shown by using a chain-of-custody system that
identifies and accompanies a sample between the time it is collected and
the time it is analyzed.
Sampling techniques and procedures are discussed in detail in Chapter
Five, "Sampling."
Statements
Inspectors can obtain formal statements from persons who have personal,
firsthand knowledge of facts pertinent to a potential violation. This
statement of facts is signed and dated by the person who can testify to
those facts in court, and it may be admissible as evidence.
The principal objective of obtaining a statement is to record in writing,
clearly and concisely, relevant factual information so that it can be used
to document an alleged violation.
NPDES Inspection Manual 2-16 June 1984
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Chapter Two Documentation
Procedures and Considerations
• Determine the need for a statement. Will it provide useful infor-
mation? Is the person making the statement qualified to do so by
personal knowledge?
• Ascertain all the facts and record those which are relevant and
which the person can verify in court. Make sure all information
is factual and firsthand. Avoid taking statements that cannot be
personally verified.
• In preparing a statement:
Use a simple narrative style; avoid stilted language.
- Narrate the facts in the words of the person making the state-
ment.
Use the first-person singular ("I am manager of ...").
- Present the facts in chronological order (unless the situation
calls for other arrangement).
• Positively identify the person (name, address, position).
• Show why the person is qualified to make the statement.
• Present the pertinent facts.
• Have the person read the statement and make any necessary correc-
tions before signing. If necessary, read the statement to the
person in the presence of a witness.
- All mistakes that are corrected must be initialed by the person
making the statement.
• Ask the person making the statement to write a brief concluding
paragraph indicating that he or she read and understood the state-
ment. (This safeguard will counter a later claim that the person
did not know what he or she was signing.)
• Have the person making the statement sign it.
• If he or she refuses to sign the statement, elicit an acknowledge-
ment that it is true and correct. Ask for a statement in his or
her own hand ("I have read this statement and it is true but I am
not signing it because..."). Failing that, declare at the bottom
of the statement that the facts were recorded as revealed and that
the person read the statement and avowed it to be true. Attempt to
have any witness to the statement sign the statement including
witness' name and address.
• Provide a copy of the statement to the signer if requested.
NPDES Inspection Manual 2-17 June 1984
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Chapter Two Documentation
Photographs
The documentary value of photographs ranks high as admissible evidence.
Clear photos of relevant subjects, taken in proper light and at proper lens
settings, provide an objective record of conditions at the time of inspec-
tion. If possible, photographs should be taken in such a way as to keep
"sensitive" buildings or operations out of background.
When a situation arises that dictates the use of photographs, the inspector
should obtain the permittee's approval to take photographs. The inspector
is to be tactful in handling any concerns or objections a permittee may
have about the use of a camera. In some cases, the inspector may explain
to the permittee's representative that waste streams, receiving waters, and
wastewater treatment facilities are public information, not trade secrets.
In the event the permittee's representative still refuses to allow photo-
graphs and the inspector believes the photographs will have a substantial
impact on future enforcement proceedings, Regional enforcement attorneys
should be consulted for further instructions. At all times the inspector
is to avoid confrontations that might jeopardize the completion of the in-
spection.
Photographs may always be taken from areas of public access (e.g. across a
stream, from a parking lot, etc).
Equipment
A single lens reflex camera may be used whenever one is available. This
type of camera will take high-quality photographs, enable the inspector to
use a variety of film speeds, and allow the use of appropriate lenses.
Fully automatic pocket cameras can often be used for routine inspections to
record the conditions of the facility during the inspection.
All photographs should be made with color print film because additional
equipment, such as projector and screen, are not needed to review the
photographs. Also, the negatives are easily duplicated and the prints can
be enlarged and distributed as needed.
Scale, Location, and Direction
It is sometimes useful to photograph a subject from a point that will indi-
cate the location and direction of the subject. The addition of an object
of known size (e.g., a person, an auto) will help indicate the approximate
size of the subject.
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Chapter Two Documentation
Safety
In areas where there is a danger of explosion, flash photographs should not
be taken. If there is a danger of electrical shock, photographs should be
taken from a distance known to be safe.
Documenting Photographs
A photographic log should be maintained in the Inspector's Field Notebook
for all photographs taken during an inspection, and the entries are to be
made at the time the photograph is taken. These entries are to be numeri-
cally identified so that after the film is developed the prints can be
serially numbered corresponding to the logbook descriptions and, if neces-
sary, pertinent information can be easily transferred to the back of the
photograph. The log entries are to include:
Name and signature of the photographer and witness;
Description of film used (i.e., its expiration date, ASA number,
origin, etc.);
Type of camera and attachments;
Focal length of the lens being used;
F-stop and shutter speed at which the camera is set;
Lighting conditions encountered;
Time of day, weather conditions;
Date;
Location; and
A brief description of the subject being photographed.
When a pocket camera is used to record conditions of the facility, less
formal documentation procedures may be used.
Drawings and Maps
Schematic drawings, maps, charts, and other graphic records can be useful
in supporting violation documentation. They can provide graphic clarifica-
tion of site location relative to the overall facility, relative height and
size of objects, and other information which, in combination with samples,
photographs, and other documentation, can produce an accurate, complete,
evidence package.
Drawings and maps should be simple and free of extraneous details. Basic
measurements and compass points should be included to provide a scale for
interpretation.
Drawings and maps should be identified by source and be dated.
HPDES Inspection Manual 2-}$June 1984
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Chapter Two Documentation
Printed Matter
Brochures, literature, labels, and other printed matter may provide impor-
tant information regarding a facility's conditions and operations. These
materials may be collected as documentation if, in the inspector's judg-
ment, they are relevant.
All printed matter should be identified with date, inspector's initials,
and origin.
Mechanical Recordings
Records produced electronically or by mechanical apparatus can be entered
as evidence. Charts, graphs, and other "hard copy" documents should be
treated as documentation and handled accordingly.
Copies of Records
Records and files may be stored in a variety of information retrieval
systems, including written or printed materials, computer or electronic
systems, or visual systems such as microfilm and microfiche.
When copies of records are necessary for an inspection report, storage and
retrieval methods must be taken into consideration:
• Written or printed records can generally be photocopied on-site.
Portable photocopy machines may be available to inspectors through
the Regional Office. When necessary, however, inspectors are
authorized to pay a facility a "reasonable" price for the use of
facility copying equipment.
- At a minimum, all copies made for or by the inspector
should be initialed and dated for identification purposes.
(See identification details below.)
- When photocopying is impossible or impracticable, close-up
photographs may be taken to provide suitable copies.
• Computer or electronic records may require the generation of
"hard" copies for inspection purposes. Arrangements should be
made during the opening conference, if possible, for these copies.
- Photographs of computer screens may possibly provide
adequate copies of records if other means are impossible.
NPDES Inspection Manual 2-20 June 1984
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Chapter Two Documentation
• Visual systems (microfilm, microfiche) usually have photocopying
capacity built into the viewing machine, which can be used to
generate copies.
- Photographs of the viewing screen may provide adequate
copies if "hard" copies cannot be generated.
Identification Procedures
Immediate and adequate identification of records reviewed is essential to
ensure the ability to identify records throughout the Agency custody
process and to ensure their admissibility in court. When inspectors are
called to testify in court, it is imperative that they be able to
positively identify each particular document and state its source and the
reason for its collection.
Initial, date, number, and write in the facility's name on each record, and
log these items in the field notebook.
• Initialing/Dating. Each inspector should develop a unique system
for initialing (or coding) and dating records and copies of
records so that he or she can easily verify their validity. This
can be done by initialing each document in a similar position, or
by another method, at the time of collection. Both the original
and copy should be initialed. All record identification notations
should be made on the back of the document.
The inspector must be able to positively identify that he or she
so marked the document.
• Numbering. Each document or set of documents substantiating a
suspected violation or violations should be assigned an
identifying number unique to that document. The number should be
recorded on each document and in the field notebook.
• Logging. Documents obtained during the inspection should be
entered in the field notebook by a logging or coding system. The
system should include the identifying number, date, and other
relevant information:
- The reason for copying the material (i.e., the nature of the
suspected violation or discrepancy).
- The source of the record (i.e., type of file, individual who
supplied record).
- The manner of collection (i.e., photocopy, other arrangements).
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Chapter Two Documentation
General Considerations
• Originals must be returned to the proper personnel or to their
correct location.
• Related records should be grouped together.
• Confidential business records should be handled according to the
special confidential provisions discussed below.
Routine Records
The inspector may find it convenient to make copies of some records such as
lab analysis sheets and data summaries to refresh his or her memory when
preparing an inspection report. It is not always necessary to follow the
formal identification and logging requirements when such records are
obtained for general information purposes or to aid in the preparation of
routine inspection reports.
Confidential Information
Disclosure of Official Information
Inspectors may give general information about EPA programs and activities
and describe what they are doing but should be cautious about divulging
specific information regarding an inspection. It is permissible to discuss
with the permittee's representative deficiencies encountered during an
evaluation of self-monitoring procedures and the action required to correct
these deficiencies. But it is not advisable to discuss information
collected during the course of an inspection that may indicate that a
violation has occurred. Therefore, when an inspector has reason to believe
that there may be cause for an enforcement action, no information should be
disclosed before consulting with the Regional Office. Caution should be
exercised in disclosing findings or speculating on the type of action the
Agency may choose to take.
Trade Secrets and Confidential Information
Trade secrets and confidential information are protected from public
disclousre by Section 308(b)(2) of the Clean Water Act (1977). The type of
information that may be considered business information is defined in Title
40, Code of Federal Regulations, Part 2. (40 CFR Part 2.)
Section 308(a)(4) of the CWA states that an inspector may sample an
effluent, request information, have access to the location of the effluent,
and inspect any monitoring equipment. The information that is collected is
available to the public. If a permittee does not want inspection
information to be available to the public, it must request the
NPDES Inspection Manual 2-22 June 1984
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Chapter Two Documentation
Administrator of EPA to consider the information confidential. The
permittee must show that the information, if made available, would divulge
trade secrets. The information may then be classified confidential, but
may still be disclosed to authorized representatives of EPA concerned with
enforcing the Act.
Therefore, a business is entitled to a claim of confidentiality for all in-
formation that an inspector requests or has access to; but a business may
not refuse to release information requested by the inspector under the
authority of Section 308 of the Act on the grounds that the information is
considered confidential or a trade secret. The claim of confidentiality
relates only to the public availability of such data and cannot be used to
deny access to a facility to EPA inspectors performing duties under Section
308 of the Act.
Handling Confidential Information
Routine security measures will help ensure that reasonable precautions are
taken to prevent unauthorized persons from viewing confidential informa-
tion. When practical circumstances prohibit the inspector from following
the procedures exactly, the inspector is expected to take steps for protec-
tion of the information that will achieve this objective. All confidential
information received must be marked as such and placed in a locked filing
cabinet or a safe immediately following the completion of the inspection.
A chain-of-custody record must be maintained for all confidential informa-
tion.
While Traveling. The inspector may be on the road for several days while
doing inspections. It is the inspector's responsibility to ensure that the
information he or she collects is handled securely.
• Documents and field notes are considered secure if they are in the
physical possession of the inspector and are not visible to others
while in use.
• Inspection documents contain sensitive information and should be
kept in a locked briefcase. If it is impractical to carry the
briefcase into a given situation, the briefcase may be stored in a
locked area such as a motel room or trunk of a motor vehicle.
• Physical samples should be placed in locked containers and stored
in a locked portion of a motor vehicle. The chain-of-custody
procedures provide further protection for ensuring the integrity of
the sample.
In the Office. Only personnel authorized by the Regional Administrator,
Division Director, or Branch Chief will be allowed access to the file.
An access log should be maintained for all transactions. Copies of
information marked "trade secret" and/or "confidential" should not be made
unless written authorization has been obtained from the Regional
Administrator, Division Director, or Branch Chief. Requests for access to
confidential information by any member of the public, or by an employee of
NPDES Inspection Manual 2-23 June 1984
-------
Chapter Two Documentation
a State, local, or Federal agency, shall be handled according to the
procedures contained in the Freedom of Information Act regulations (40 CFR
Part 2). All such requests shall be referred to the responsible Regional
organizational unit.
NPDES Inspection Manual 2-24 June 1984
-------
Chapter Two
5 Closing Conference
To achieve the most effective results from compliance inspections, it is
essential for the inspector to promptly communicate the results to the
facility management and/or operating personnel. However, the inspector's
discussion should be limited to specific findings of the visit. If appro-
priate, the findings should be compared with the permittee's NPDES permit
requirements, consent decrees, administrative orders, and other enforcement
actions.
Precautions and Guidelines
Although a discussion of the inspection results is important, certain pre-
cautions are essential:
• The inspector should not discuss compliance status or any legal
effects or enforcement consequences with the permittee's represen-
tative or with facility operating personnel.
• The inspector should refrain from recommending a particular con-
sultant or consulting firm, even if asked to do so. Inspectors
should tell the permittee's representative to contact a profes-
sional society or approved listing for advice concerning this
matter.
These guidelines are subject to rules promulgated by the Regional Admini-
strator or State Director regarding permittee contacts in the Region/State.
Deficiency Notice
The inspector may issue a Deficiency Notice following an inspection that
uncovered existing or potential problems in a permittee's self-monitoring
program. Issuing a Deficiency Notice at the completion of an inspection
NPDES Inspection Manual 2-25 June 1984
-------
Chapter Two Closing Conference
provides a swift and simple method for improving the quality of data from
NPDES self-monitoring activities. It also helps the permittee to comply
with the self-monitoring requirements of the permit. This tool is to be
used in conjunction with any type of NPDES compliance inspection during
which the inspector identifies problems with the permittee's
self-monitoring activities.
The Deficiency Notice is to be used by the inspector only to alert permit-
tees to deficiencies in their self-monitoring activities. The enforcement
office of the regulatory authority, not the inspector, handles effluent
violations.
Inspectors can issue the Deficiency Notice to a permittee immediately fol-
lowing a compliance inspection if they discover any permit deficiences in
the seven categories that the Notice addresses.
NPDES Inspection Manual 2-26 June 1984
-------
Chapter Two
6 Inspection Report
The adequacy of compliance follow-up to correct problems or deficiencies
noted during an inspection depends in a large part on the inspection report
package prepared by the inspector. The preceding chapter detailed the pro-
cedures for collecting and substantiating this information. Once collec-
ted, however, the material must be organized and arranged in a manner that
will allow compliance personnel to make maximum use of the information.
The information presented in this section provides general guidelines for
organizing evidence and preparing an inspection report.
Objective of the NPDES Inspection Report
The objective of an inspection report is to organize and coordinate all in-
spection information and evidence in a comprehensive, usable manner. To
meet this objective, information in an inspection report must be:
• Accurate. All information must be factual and based on sound in-
spection practices. Observations should be the verifiable result
of firsthand knowledge. Compliance personnel must be able to de-
pend on the accuracy of all information.
• Relevant. Information in an inspection report should be pertinent
to the subject of the report. Irrelevant facts and data will
clutter a report and may reduce its clarity and usefulness. Per-
sonal comments and opinions should be avoided.
• Comprehensive. Suspected violation(s) should be substantiated by
as much factual, relevant information as is feasible to gather.
The more comprehensive the evidence is, the better and easier the
prosecution task will be.
NPDES Inspection Manual2-27~~June 1984
-------
Chapter Two Inspection Report
• Coordinated. All information pertinent to the subject should be
organized into a complete package. Documentary support (e.g.,
photographs, statements, sample documentation, etc.) accompanying
the report should be clearly referenced so that anyone reading the
report will get a complete, clear overview of the situation.
• Objective. Information should be objective and factual; the re-
port should not speculate on the ultimate result of any factual
findings.
• Clear. The information in the report should be presented in a
clear, well-organized manner.
• Neat and Legible. Allow time to prepare a neat, legible report,
with complete clear copies of all documents.
Elements of a Report
Although specific information requirements for an inspection report will
vary, most reports will contain the same basic elements:
• NPDES Compliance Inspection Report Form
• Supplementary narrative information
• Copies of completed checklists
• Documentary support
NPDES Compliance Inspection Report Form
It is the inspector's responsibility to report all compliance inspection
activities by completing the current Compliance Inspection Report Form as
soon as possible after the inspection. The Federal or State compliance
office should forward the inspection report form to the regulatory
authority no later than thirty days after completion of the inspection.
Copies should be sent to the permittee in a timely manner except when
formal enforcement procedures are under way. In this instance, the case
attorney will direct any disclosure of data.
Supplementary Narrative Information
Supplementary narrative information could be a memo in the case of routine
inspections or could be a narrative report where major violations are
detected. When a narrative report is necessary to fully describe a
compliance inspection, the contents of the report should focus on
supporting or explaining the information provided in the Compliance
Inspection Report Form.
NPDES Inspection Manual 2-28 June 1984
-------
Chapter Two Inspection Report
The narrative report should be a concise, factual summary of observations
and activities, organized in a logical, legible manner, and supported by
specific references to accompanying documentary support.
A work plan will simplify preparation and will help ensure that information
is organized in a usable form. Basic steps in writing the narrative report
include:
• Reviewing the Information. The first step in preparing the narra-
tive is to collect all information gathered during the inspection.
The inspector's field notebook should be reviewed in detail. All
evidence should be reviewed for relevance and completeness. Gaps
may need to be filled by a phone call or, in unusual
circumstances, by a follow-up visit.
• Organizing the Material. The information may be organized in many
forms depending on the individual need, but should present the
material in a logical, comprehensive manner. The narrative should
be organized so that it will be understood easily by the reader.
• Referencing Accompanying Material. All documentary support accom-
panying a narrative report should be clearly referenced so that
the reader will be able to locate these documents easily. The
Documentation section elsewhere in this chapter provides details
on document identification. All documentary support should be
checked for clarity prior to writing the report.
• Writing the Narrative Report. Once the material collected by the
inspector has been reviewed, organized, and referenced, the narra-
tive can be written. The purpose of the narrative is to record
factually the procedures used in, and findings resulting from, the
evidence-gathering process. The inspector should refer to routine
procedures and practices used during the inspection, but should
describe facts relating to potential violations and discrepancies
in detail. The field notebook is a guide for preparing the narra-
tive report.
If the inspector has followed the steps presented in this manual, the re-
port will develop logically from the organizational framework of the in-
spection. In preparing the narrative, simplicity should be a prime con-
sideration:
Use a simple writing style; avoid stilted language.
Use an active, rather than passive approach: (e.g., "He said
that..." rather than "It was said that...").
Keep paragraphs brief and to the point.
Avoid repetition.
Proofread the narrative carefully.
NPDES Inspection Manual 2^June 1984
-------
Chapter Two Inspection Report
Copies of Completed Checklists
Comprehensive checklists are included in the technical chapters of this
manual. When appropriate, these concise checklists may be used by the
inspector to collect information during the inspection. Copies of all
completed checklists should be included in the inspection report.
Documentary Support
All documentation that is produced or collected by the inspector to provide
evidence of suspected violations should be included in the inspection
report. Types of documentation include the field notebook, statements,
photographs, drawings and maps, printed matter, mechanical recordings, and
copies of records. The Documentation section elsewhere in this chapter
provides details on obtaining and organizing this material.
The Permit Compliance System (PCS)
The inspection office should make sure that all data listed in Section A of
the NPDES Compliance Inspection Report are entered into the PCS, which is
used for national tracking of NPDES permit information. An inspection is
not credited to the inspection program office until coded into the PCS.
Timely completion of reports is therefore essential for the effective
follow-up of a compliance inspection. Every effort should be made to en-
sure that data are entered within 15 days of completion of the inspection.
NPDES Inspection Manual 2-30 June 1984
-------
Chapter Three
Recordkeeping and Reporting
Contents Page
Authority and Scope 3-1
Inspection Objectives 3-1
Permit Verification 3-2
Recordkeeping and Reporting Evaluation Procedures 3-2
Compliance Schedule Status Review 3-4
POTW Pretreatment Requirements Review 3-6
In-Depth Investigations 3-7
Investigation Procedures 3-7
Records, Reports, and Schedules Checklist 3-9
NPDES Inspection Manual 3-i June 1984
-------
Chapter Three
Recordkeeping and Reporting
Authority and Scope
Statutory Recordkeeping Authority: Clean Water Act §308, §402
Regulatory Requirements: 40 CFR Parts 122.41 and 122.48
Inspection Authority: Clean Water Act §308
The NPDES permit system requires permittees to maintain records and to
report periodically on the amount and nature of the waste components in the
effluent. The permit stipulates recordkeeping and reporting conditions.
Evaluations are conducted at all permittee facilities to determine com-
pliance with permit requirements. The procedures listed below should be
used for these routine inspections. If suspected violations are uncovered
during the routine evaluation, a more in-depth investigation should be con-
ducted.
Inspection Objectives
A review of facility records should determine that recordkeeping require-
ments are being met. In particular:
• Is all required information available?
• Is the information current?
• Is the information being maintained for the required period of
time? Do the records reviewed indicate areas needing further
investigation?
NPDES Inspection Manual 3-1 June 1984
-------
Chapter Three Recordkeeping and Reporting
Permit Verification
[Refer to Checklist, page 3-9.]
Beginning in the records inspection phase and continuing throughout the in-
spection, the facility's operations should be compared with the permit to
verify that required permit activities are correct, current, and complete.
Much of the information needed to verify the permit can be quickly obtained
and should be collected during the opening conference and compared with the
facility permit. This information includes:
• Correct name and address of facility;
• Correct name and location of receiving waters; and
• Number and location of discharge points.
During the Records Inspection. The inspector should check for records that
will verify that:
• If discharges differ from those stated in the permit, notification
has been made to EPA or to the State;
• Accurate records of influent quality and volume are maintained when
appropriate;
• Notification of a permit violation has been made to EPA or the
State; and
• Notification of bypassing has been made to EPA or to the State.
During the Walk-Through Inspection. The Inspector should verify the
following requirements of the permit through visual observations and sense
of smell:
• Number and locations of dischargers are as described in the permit;
and
• All dischargers are in accordance with the general provisions of
the permit, such as, no obnoxious odors, no discharge, no visible
entrained solids in discharge, and no fish or vegetation kills near
the outfalls.
Recordkeeping and Reporting Evaluation Procedures
[Refer to Checklist, page 3-9.]
1. Review permit to determine recordkeeping and reporting requirements.
2. Check the records required by the permit to verify that the require-
ments are being met, including record maintenance for a minimum period
of 3 years. These records may include:
NPDES Inspection Manual 3^2June 1984
-------
Chapter Three Recordkeeping and Reporting
• Sampling and Analysis Data
- Dates, times, locations of sampling
- Analytical methods and techniques
- Results of analyses
- Dates and times of analyses
- Name(s) of analyses and sampling personnel
• Monitoring Records
- Discharge Monitoring Reports (DMR's). These would include flow,
pH, D.O., etc., as required by permit
- Original charts from continuous monitoring instrumentation
• Laboratory Records
- Calibration and maintenance of equipment
- Calculations
- QA/QC analysis data
• Facility Operating Records (Daily) (when required)
- Daily operating log
- Summary of all laboratory tests run and other required
measurements
- Chemicals used (such as pounds of chlorine per day)
- Weather conditions (temperature, precipitation, etc.)
- Equipment maintenance completed and scheduled
• Plant Records*
- Plant O&M Manual
- Percent removal records
- "As built" engineering drawings
- Copy of construction specifications
- Equipment supplier manual
- Data cards on all equipment
• Spill Prevention Control and Countermeasure (SPCC) Plan
When required, a properly completed SPCC Plan should be available.
The inspector may also complete the SPCC inspection form and
forward the completed form to the appropriate program for follow-up
action.
• Best Management Practices
Two types of Best Management Practices (BMP) are included in NPDES
permits:
*These items should be available, but they are only required for those
facilities built with Federal construction grant funds.
NPDES Inspection Manual 3-3 ~ June 1984
-------
Chapter Three Recordkeeping and Reporting
- BMP plans to minimize or prevent the potential for release of
significant amounts of any toxic or hazardous pollutants to
public waters. The plans may discuss general operation and
maintenance of the plant, good housekeeping procedures on the
facility grounds, and other plans and procedures specific to best
management of the facility.
- Site-specific BMPs to address particular toxic or hazardous
chemicals or other conditions particular to the facility. Site-
specific BMPs may include procedures, monitoring requirements,
construction of barriers such as dikes and berms, or other appro-
priate measures for solving specific problems.
• Management Records
- Average monthly operating records
- Annual reports
- Emergency conditions (power failures, bypass and chlorine failure
reports, etc.)
• Pretreatment Records
- Industrial Waste Ordinance (or equivalent documents)
- Inventory of industrial waste contributors including compliance
records and user charge information.
3. Document all inspection activity (see Chapter Two, Section 4). Inade-
quacies, discrepancies, or other problems uncovered during this review
may warrant an in-depth investigation.
Compliance Schedule Status Review
[Refer to Checklist, page 3-10.]
If the permit contains a compliance schedule, a status review should be
conducted to determine:
• Whether or not the permittee is currently conforming to the com-
pliance schedule and, if not, whether final requirements will be
achieved on time;
• The accuracy of reports relating to compliance schedules;
• The length of delay associated with a particular construction
violation;
• Whether any schedule violations are the result of matters beyond
the control of the discharger; or
• Whether or not requests for permit modifications are valid.
NPDES Inspection Manual 3r5 June 1984
-------
Chapter Three Recordkeeping and Reporting
Construction Progress. It is important to know whether contracts for labor
and material are timely and whether the permittee or the permittee's en-
gineering consultant is monitoring progress. These aspects are extremely
important, particularly in plants where there are likely to be numerous
contracts for labor and equipment. If the permittee or the engineering
consultant reports that construction or the acquisition of equipment is
behind schedule, the inspector should:
• Ask to see the permittee's or the resident engineer's progress
report and determine whether the report indicates that the final
compliance schedule required by the permit can be met;
• If the report indicates that the final date will not be met, advise
the permittee that the compliance schedule of the NPDES permit re-
quires the permittee to notify the permit-issuing authority
promptly of any possible delay in achieving compliance and of mea-
sures taken to minimize the delay; and
• Inquire whether the facility superintendent or chief operator and
operating personnel are receiving adequate training concerning the
operational aspects of the new treatment unit while construction
work is in full progress. They must be prepared to perform the es-
sential operating functions when the facility is placed in service.
Contract and Equipment Orders. The inspector should review the appropriate
documents to determine whether the permittee has obtained the necessary ap-
proval from the appropriate agencies in order to begin construction. The
inspector should determine the start and completion dates or scheduled
delivery dates in service or equipment contracts.
Authorization and Financing. If the necessary treatment works are not in
place, the inspector should ascertain whether the permittee has authority
to construct the necessary installation (corporate resolutions, etc.) and
has made arrangements for proper financing (mortgage commitments, etc.).
Attainment of Operational Status. If construction has been completed but
operational status not yet been attained, the inspector should determine
whether appropriate procedures are being used to ensure attainment of
working levels at the earliest possible time.
The inspector should verify that:
• Adequate self-monitoring procedures have been initiated. It is
especially important that the operational and effluent quality
result be reviewed to determine whether progress is being made
toward optimum efficiency in each treatment unit and in the entire
plant;
• Adequate recordkeeping procedures have been established and
initiated; and
NPDES Inspection Manual 3-5 June 1984
-------
Chapter Three Recordkeeplng and Reporting
• Adequate work schedules and assignments have been established.
(For municipal facilities, the O&M Manual should provide the
essential guidance in this regard.)
POTW Pretreatment Requirements Review
[Refer to Checklist, page 3-11.]
The inspector must do the following when addressing pretreatment require-
ments:
1. Determine the status of the pretreatment program by the POTW.
• Has the program been approved by EPA/State or is the approval in
progress?
• Is the POTW in compliance with the enforceable schedule? If not,
what information is lacking, why is the information overdue, and
what does the POTW intend to do to get back on schedule?
2. Collect information about the compliance status of contributing indus-
trial facilities with Categorical Pretreatment Standards. The inspec-
tor should review POTW records to determine:
- Number of contributing industries;
- Whether these industries have been notified of applicable stan-
dards;
- Whether industries have submitted baseline reports to the POTW;
- Number of contributing industries in compliance with standards;
and
- Whether contributing industries with compliance schedules are
meeting applicable schedule deadlines.
3. Collect information about the status of compliance of contributing
industries with Prohibited Limits (403.5) and Local Limits, if more
stringent than EPA Categorical Pretreatment Standards. This applies
in cases where the POTW determines that more stringent discharge
requirements are needed due to industrial loadings in relation to
available POTW treatment systems. The inspector should report:
• How many and which industrial facilities appear not to be in
compliance;
• Any reasons for non-compliance; and
• Any follow-up action recommended, such as other inspections,
monitoring, review of discharge limits, etc.
NTOES Inspection Manual IFFJune 1984
-------
Chapter Three Recordkeeplng and Reporting
In-Depth Investigations
An in-depth inspection of a permittee's records and reports will be con-
ducted when necessary to substantiate a suspected violation, to verify
self-monitoring data that may be used as corroborative evidence in an en-
forcement action, or to confirm apparent sampling, analysis, or reporting
discrepancies discovered during the limited inspection. Discrepancies war-
rant an in-depth review if, for example:
• The discharge does not meet required standards and no definite
operational problems have been established;
• Self-reported data are suspected to be grossly inaccurate and the
problem appears to be with recordkeeping procedures and/or the
filing of reports;
• The cursory review indicates omissions or laxity in the preparation
of records; or
• There is evidence of falsification of records.
If more guidance or assistance is needed in carrying out an in-depth
investigation, the inspector should confer with the National Enforcement
Investigations Center.
Investigation Procedures
1. Determine the investigation objective. (What is the specific purpose
of the investigation?)
2. Determine what information is needed. (What specific data will sub-
stantiate a violation or respond to the investigation objective?)
3. Determine the data source. (What records will contain these required
data?)
A. Review inspection authority. Authority to inspect under §308 is
limited to those records required by the permit. Specific authority
may be necessary to inspect other documents.
5. Inspect direct and indirect sources of data. Look at those records
likely to provide the required data directly. In the absence of
direct data, indirect sources of information can be used to develop a
network of information relevant to the data being sought.
6. Take statements from qualified facility personnel. (See Chapter Two,
Section 4 for procedures.)
NPDES Inspection Manual jFT June 1984
-------
Chapter Three Recordkeeplng and Reporting
7. Prepare documentation. Copy and identify all records relevant to the
information being sought. (See Chapter Two, Section 4 for specific
procedures.)
8. Follow confidentiality procedures. Any record inspected may be
claimed by the facility as confidential. Such records must be treated
in accordance with Agency procedures (see page 2-22).
NPDES Inspection Manual 3-8 June 1984
-------
BecoEds, Reports, and Schedules Checklist
A. PeraLt Verification
YES NO N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
INSPECTION OBSERVATIONS VERIFY INFORMATION CONTAINED IN PERMIT
1. Correct name and mailing address of permittee.
2. Facility is as described in permit.
3. Notification has been given to EPA/State of new, different, increased discharges.
4. Accurate records of influent volume are maintained, when appropriate.
5. Number and location of discharge points are as described in the permit.
6. Name and location of receiving waters are correct.
7. All discharges are permitted.
B. Recordkeepdig and Reporting BraluatLon
YES NO N/A
RECORDS AND REPORTS ARE MAINTAINED AS REQUIRED BY PERMIT
1. All required information is available, complete, and current; and
2. Information is maintained for required period.
3. Analytical results are consistent with the data reported on the DMR's.
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
4. Sampling and Analysis Data are adequate and include:
a. Dates, times, location of sampling
b. Name of individual performing sampling
c. Analytical methods and techniques
d. Results of analysis
e. Dates of analysis
f. Name of person performing analysis
g. Instantaneous flow at grab sample stations
Yes No N/A
Yes No N/A
5. Monitoring records are adequate and include
a. Flow, pH, D.O., etc. as required by permit
b. Monitoring charts
Yes No N/A
6. Laboratory equipment calibration and maintenance records are adequate.
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
7. Plant Records are adequate* and include
a. O&M Manual
b. "As-built" engineering drawings
c. Schedules and dates of equipment maintenance and repairs
d. Equipment supplies manual
e. Equipment data cards
*Required only for facilities built with Federal construction grant funds.
3-9
-------
Itecords, Reports, and Schedules Checklist
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
8. Pretreatment records are adequate and include:
a. Industrial Waste Ordinance (or equivalent documents)
b. Inventory of industrial waste contributors, including:
1. Compliance records
2. User charge information
9. SPOC properly completed, when required.
10. Best Management Practices Program available, when required.
C. Compliance Schedule Status Bevlew
YES NO N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
THE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
PERM1T1EE IS MiEi'lNU THE UMHJANCE SCHEDULE
The permittee has obtained necessary approvals to begin construction.
Financing arrangements are complete.
Contracts for engineering services have been executed.
Design plans and specifications have been completed.
Construction has begun.
Construction is on schedule.
Equipment acquisition is on schedule.
Construction has been completed.
Start-up has begun.
The permittee has requested an extension of time.
The permittee has met compliance schedule.
3-10
-------
YES NO N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
tecacds, Reports, and Schedules Checklist
TL K7IW PnK-nmtiT RfVfiftimpnt-g lb*r|cqr
THE FACrLTIY IS SUBJECT TO PRETREATMENT REQUIREMENTS
1. Status of POIW Pretreatment Program
a. The POIW Pretreatment Program has been approved by EPA. (If not, is approval
in progress? )
b. The POTW is in compliance with the Pretreatment Program Compliance Schedule.
(If not, note why, what is due, and intent of the POTW to remedy)
2. Status of Compliance with Categorical Pretreatment Standards.
a. How many industrial users of the POTW are subject to Federal or State
Pretreatment Standards?
b. Are these industries aware of their responsibility to comply with
applicable standards?
c. Have baseline monitoring reports (403.12) been submitted for these
industries?
i. Have categorical industries in noncompliance (on BMR reports)
submitted compliance schedules?
ii. How many categorical industries on compliance schedules are meeting
the schedule deadlines?
d. If the compliance deadline has passed, have all industries submitted 90 day
compliance reports?
e. Are all categorical industries submitting the required semiannual report?
f . Are all new industrial discharges in compliance with new source
pretreatment standards?
g. Has the POTW submitted its annual pretreatment report?
h. Has the POTW taken enforcement action against noncomplying
industrial users?
i. Is the POIW conducting inspections of industrial contributors?
3. Are the industrial users subject to Prohibited Limits (403.5) and local limits
more stringent than EPA in compliance?
(If not, explain why, including need for revision of limits.)
3-11
-------
Chapter Four
Facility Site Review
Contents Page
Objectives 4-1
Physical Inspection of the Facility 4-2
General Indicators 4-3
Primary Clarifier 4-4
Secondary Biological Treatment Units 4-5
Secondary Clarifier 4-6
Physical Treatment Units 4-6
Sludge Handling 4-7
Sludge Anaerobic Digestion 4-7
Sludge Drying/Filtering 4-8
Sludge Disposal 4-9
Miscellaneous 4-9
Maintenance of Facilities and Equipment 4-10
Flow Measuring Equipment 4-10
Chemical Treatment Units 4-10
Oil Separation 4-11
General Housekeeping 4-11
Polishing Ponds or Tanks 4-11
Production Changes 4-11
Operation Evaluation 4-12
Policies and Procedures 4-12
Staffing 4-13
Management Controls 4-13
Maintenance Evaluation 4-13
References 4-16
Facility Site Review Checklist 4-24
List of Tables
4-1 Operations and Maintenance Function Evaluation Questions 4-17
Inspection Manual 2fri June 1984
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Chapter Four
Facility Site Review
Objectives
In performing a facility site review, an inspector examines areas on the
permittee's premises where pollutants are generated, pumped, conveyed,
treated, stored, or disposed. The inspector also conducts a visual inspec-
tion of monitoring equipment.
The proper conduct of a facility site review requires that the inspector
have a full understanding of the treatment processes used at the facility
and how each process fits into the overall treatment scheme.
The objectives of a facility site review are to:
• Assess the conditions of the permit in regard to current facility
processes and operations;
• Evaluate the permittee's operation and maintenance activities; and
• Check on the completeness and accuracy of the permittee's perfor-
mance/compliance records.
The overall review of the facility allows the compliance inspector to gain
a feeling for the facility being inspected, to review areas that may indi-
cate problems with effluent limitations, and to evaluate overall perfor-
mance of the treatment facility.
The information presented in this chapter is comprehensive and inspectors
should use only that information that is applicable to the situation at
hand.
A Facility Site Review Checklist for inspectors' use is included at the end
of this chapter.
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Chapter Four Facility Site Review
Physical Inspection of the Facility
During the physical "walk-through" of the facility, the inspector should
look at the areas listed below. Because these areas may contain potential
problems, the physical inspection should be carefully documented. Areas
that should be covered are:
• Influent characteristics, including:
- combined sewer loads,
- infiltration/inflow,
- industrial contributions, and
- diurnal/seasonal loading variations;
• Process control;
• Unit operations;
• Equipment condition; and
• Other conditions particular to the plant.
The manual, Performance Evaluation and Trouble Shooting at Municipal
Wastewater Facilities, published by the Municipal Operations Branch of the
EPA, MO #16, January 1978 is a good reference for the above areas.
The physical inspection may lead to the following determinations:
• Whether or not there is a major design problem that requires an
engineering solution;
• Problem areas that can be solved through the evaluation (and even-
tual correction) of operation and maintenance functions; or
• Periodic equipment malfunctions that need to be addressed by com-
plete overhaul or replacement of equipment.
If the first condition, a facility design problem, exists, one of the re-
commendations will be to develop engineering solutions. In that case, the
inspector must evaluate the operation and maintenance functions from the
point of view of what can be done to minimize problems, if the design
problems continue to exist.
When the second condition exists, the inspector should use the facility in-
spection findings to tailor the evaluation of the operation and maintenance
functions. This information would enable the inspector to look for speci-
fic practices that either contribute to or cause the problems uncovered in
the physical inspection.
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Chapter Four Facility Site Review
When conducting the walk-through, the inspector should be aware of and
should look for indicators of potential problems. The presence of these
indicators will give the inspector an idea of the types of problems pre-
sent, the parts of the treatment process causing the problems, and the
potential solution to existing problems. Indicators for various treatment
process problems are given below.
General Indicators
• Surcharging of influent lines, overflow weirs, and other
structures;
• Flow through by-pass channels;
• Accumulation of solids and scum in wet wells, excessive scum
build-up, grease, foam, or floating material in clarifiers;
• Alternative discharge points, channels, or other areas likely to
have overflows. Discoloration of the ground may indicate past
spills at the plant and further investigation may be warranted;
• Excessive suspended solids, turbidity, foam, grease, scum, color,
and other macroscopic particulate matter in the plant effluent;
• Obnoxious odors in wet wells and grit chambers and around aerobic
and anaerobic biological units, scum removal devices, and sludge
handling facilities;
• Vital treatment units out of service for repairs. Determine when
they were out of service, the type of failure, and when the unit
will be put back in service;
• Any unusual equipment such as special pumps, floating aerators in
diffused air systems, chemical feeders, temporary construction or
structures, or any jerry-rigged systems intended to correct opera-
tional problems;
• The lack of alternative power sources in accordance with permit
requirements that can be used during electrical failures to prevent
the discharge of untreated or inadequately treated wastes;
• Collected screening, slurries, sludges, or other by-products of
treatment. Their disposal, including the runoff of wastewaters,
must be in an approved manner as to prevent entry into navigable
waters or their tributaries;
• Spills or mishandling of chemicals;
• Air slaking during storage of quicklime;
• Incomplete slaking of quicklime;
NPDES Inspection Manual 5^3 June 1984
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Chapter Four Facility Site Review
• Evidence of severe corrosion problem;
• Excessive grit in bar screen chamber;
• Excessive screen clogging;
• Ruptures in chemical feed lines;
• Excessive septage dumping by septic tank pumpers;
• Too much vibration of cyclone degritter;
• Primary clarifier or grit chamber with grease and gas bubbles
rising or with evident septic waste;
• Improper storage of all chemicals and hazardous substances with
particular attention to the proper diking of chemicals and
hazardous substances;
• Improper chlorine storage and reserve supply; and
• No recycling of filtrates and supernatant from sludge beds.
Primary Clarifier
• Evidence of short circuiting;
• Floating sludge;
• Excessive gas bubbles on surface;
• Black and odorous wastewater;
• Excessive sludge on bottom, inadequate sludge removal;
• Scum overflow or lack of adequate scum disposal, scum pit full;
• Scum rake inadequately removes scum;
• Poor suspended solids removal in primary clarifier;
• Broken scraper;
• Noisy scraper drive;
• Discharge weirs unlevel; and
• Center well on circular clarifiers has accumulated solids.
NPDES Inspection Manual 4-4 June 1984
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Chapter Four Facility Site Review
Secondary Biological Treatment Units^
• Trickling filter ponding (indicating clogged media);
• Leak at center of column of trickling filter's distribution arms;
• Clogging of trickling filter's distributor-arm orifices;
• Distribution arms do not rotate freely;
• Filter flies;
• Ice build-up on trickling filter media;
• Uneven distribution of flow on filter surface;
• Dead spots in activated sludge aeration tanks or dark foam and
bad odor;
• Air rising in clumps in activated sludge diffused aeration tank;
• Excessive air leaks in compressed air piping;
• Dark black mixed liquor in activated sludge aeration tank;
• Stable dark tan foam on aeration tanks which sprays cannot break
up;
• Failure of surface aerators;
• Inoperative air compressors;
• Thick billows of white sudsy foam on aeration tank;
• Low DO (< 1.0 mg/1) in aeration tank;
• Erosion of stabilization pond bank or dike;
• Excessive weed and algae in stabilization ponds;
• Foaming and spray in aerated lagoon;
• Development of white biomass on rotating biological contactor
media;
• Solid accumulating on rotating biological contactors;
• Excessive sloughing of biomass from rotating biological contactors;
• Excessive breaking of rotating disks in orbal units;
• Excessive breakage of paddles on brush aerators; and
NPDES Inspection Manual%-5June 19S4
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Chapter Four Facility Site Review
• Shaft, bearing, drive gear, or motor failure on disk or brush
aerators.
Secondary Clarifier
• Evidence of short circuiting;
• Sludge floating to surface;
• Excessive gas bubbles on surface;
• Fouling of overflow weirs;
• Overflow weirs unlevel;
• Deflocculation in clarifier;
• Scum rake ineffective;
• Billowing sludge;
• Sludge blanket too high;
• Pin floe in overflow;
• Excessive buildup of material in center well of circular clarifier;
and
• All sludge withdrawal ports on secondary clarifier clogged or
flowing improperly thick sludge.
Physical Treatment Units
• Filter surface clogging;
• Short filter run;
• Recycled filter backwash water in excess of five percent;
• Gravel displacement of filter media;
• Formation of mud balls in filter media;
• Loss of filter media during backwashing;
• Air binding of filter media;
• Erratic rotation of microscreen drums;
NW>KS Inspection Manual 5^ June 1984
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Chapter Four Facility Site Review
Sludge Handling
• Thickened sludge too thin;
• Fouling of overflow weirs on gravity thickeners;
• Air flotation skimmer blade binding on beaching plate;
• Poor dewatering characteristics of thermal treated sludge;
• Substantial down time of heat treatment unit; and
• Inadequate sludge removal from clarifiers or thickeners.
Sludge Anaerobic Digestion
• Floating cover of anaerobic digester tilting with heavy, little, or
no scum around the edges;
• Inadequate gas production;
• Yellow gas flame from waste gas burner;
• Gas burner not burning or inoperative;
• Moisture trap on gas line full of water;
• Supernatant exudes a sour odor from either primary or secondary
anaerobic digester;
• Foaming in supernatant in single stage or primary tank of anaerobic
digester;
• Manometer shows digester gas pressure above or below normal;
• Mechanical or gas mixers inoperative;
• Wide fluctuation of sludge temperature in anaerobic digester;
• Sludge heater inoperative;
• Excessive foaming in aerobic digestion tank;
• Inadequate supernatant removal from sludge lagoons;
• Aerobically digested sludge has objectionable odor;
NPDES Inspection Manual 4-7 June 1984
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Chapter Four Facility Site Review
• Sludge lagoons full, overflowing sludge back to plant or to natural
drainage;
• Clogging of diffusers in aerobic digester; and
• Mechanical aerator failure in aerobic digester.
Sludge Drying/Filtering
• Poor sludge distribution on drying bed;
• Dry sludge not removed from drying beds;
• Dry sludge stacked up around drying beds—runoff enters
navigable waters;
• Excessive dewatering time of sludge drying bed;
• Too many solids in centrifuge's centrate;
• Inadequate dryness of centrifugal sludge cake;
• High level of solids in filtrate;
• Thin filter cake with poor dewatering;
• Vacuum filter cloth binding;
• Improperly cleaned vacuum filter media;
• Sludge build-up on belts and/or rollers of filter press;
• Difficult cake discharge from filter presses;
• Filter cake sticks to solids-conveying equipment of filter press;
• Frequent media binding of filter press;
• Excessive moisture in filter press cake;
• Sludge blowing out of filter press;
• Objectionable odor from sludge drying lagoon;
• Broken dikes between sludge drying lagoon; and
• Sludge lagoons not lined.
NFDES Inspection Manual tt June
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Chapter Four Facility Site Review
Sludge Disposal
• Surface runoff of sludge at land application site;
• Liquid sludge, i.e., less than 10 percent solids, applied to land
fill site;
• Flies breeding and/or odors at landfill site;
• Inadequate burial of sludge at landfill site;
• Inadequate coverage of sludge in subsurface plow injection system;
• Slow drying of soil-sludge mixture in subsurface injection system;
• Sludge ponding at land applications sites;
• Inadequate groundwater monitoring at landfill or land application
sites;
• Excessive erosion at sludge landfill sites;
• Inadequate leachate collection and/or treatment at landfill or land
application sites;
• Inadequate runoff control at landfill or land application sites;
• Sludge applied to land has not been treated to significantly reduce
pathogens, according to relevant sludge disposal regulations;
• Sludge is not being transported in an appropriate and approved
vehicle, and
• Sludges disposed in landfills are not done so in accordance with
Federal, State or local regulations.
Miscellaneous
• Offensive odor in recalcining area;
• Recalcined lime tends to agglomerate into particles
one-quarter-inch in diameter or larger; and
• Large clinkers forming in lime recalcining furnace.
NPDES Inspection Manual 3^9 June 1984
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Chapter Four Facility Site Review
Maintenance of Facilities and Equipment
Inspectors should discuss maintenance programs with facility officials,
including:
• All aspects of preventive, routine, and remedial maintenance
programs including inventory of spare parts;
• Emergency operating and response programs;
• Qualifications, training, and certification of plant personnel;
• Alarm systems for power or equipment failures and the availability
of alternate power sources; and
• The regularity of housekeeping throughout the plant.
Flow Measuring Equipment
• Build up of solids in flume or weir;
• Broken or cracked flume or weir;
• Magnetic flowmeter not functioning properly;
• Stilling wells clogged, broken; and
• Weir plate damaged or not level.
Chemical Treatment Units
• Heavy corrosion evident;
• No portion measuring device at feed unit;
• pH measuring not evident at pH adjustment tank;
• Chemicals left out in open atmosphere;
• Chemicals stockpiled longer than shelf-life;
• Chemical containers stored in improper or hazardous fashion;
• Chemical tanks cars (trucks or train) stored, moved or handled
inappropriately;
• Dry chemicals spilled on floor between storage area and feed units;
• Empty chemical containers improperly disposed;
NPDES Inspection Manual 4-10 June 1984
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Chapter Four Facility Site Review
• Large containers handled improperly, container transfer equipment
not maintained;
• No appropriate sized burms or dikes at liquid chemical feed units;
• Inadequate supply of chemicals on hand;
• Chemical dust covering feed unit area or storage and transfer
areas;
• Use of an inappropriate coagulent; and
• Glass carboys (acid storage) stored or handled improperly.
Oil Separation
• Waste oil disposed improperly;
• Oily waste accumulated on floor/ground near separation unit; and
• Oil sheen on wastewater after oil-water separator.
General Housekeeping
• Facility control panel in disrepair or not in use; and
• Wastewater pipelines not clearly distinguished from product
pipelines.
Polishing Ponds or Tanks
• Contents of polishig or tanks have foul smell, excessive foams,
floating solids or oil sheens;
• Solids or scum accumulated in tank or at side of pond; and
• Evidence of polishing ponds or tanks being bypassed due to low
capacity.
Production Changes
Industries frequently make production changes because of advances in
technology and introduction of new products. Therefore, during the tour of
an industrial facility, the inspector should also inquire:
• Whether a permittee has made any changes in production processes,
raw material, amount of finished product, water use, waste
treatment processes, or other such changes. Specifically, the
inspector should determine whether the permittee has modified any
production process that would change the types or loads of
pollutants so that when the permit is reissued it will reflect
these modifications; and
NPDES Inspection Manual 5^11 June
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Chapter Four Facility Site Review
• Whether the regulatory agency was notified of such changes.
The inspector should verify any changes and include the results of the
findings and other pertinent information in the Compliance Inspection
Report. Changes in the loading to POTW's by the addition of a significant
industrial discharger or large population growth should also be ascertained
and reported.
Operation Evaluation
Operating factors affecting plant performance range from qualitative
factors such as the skills and aptitude of operators (e.g., process
knowledge and general aptitude), to physical deficiencies in laboratory
equipment or a lack of flexibility in process equipment.
The evaluation of operation functions must focus on wastewater treatment,
sludge treatment/disposal, energy recovery, and laboratory analysis. The
evaluation should be based on the following areas:
• Policies and Procedures
• Organization
• Staffing
• Planning
• Management Controls
Table 4-1 (at the end of this chapter) presents the basic review questions
that an inspector should use to evaluate operation functions.
Although each of the above evaluation areas must be covered in the review
of operation functions, the following three areas should be of particular
concern to the inspector.
Policies and Procedures
Written operating procedures and standard reference texts enable the
operator to achieve efficient plant operation. The operations manual
prepared for the facility is the most important reference that an inspector
should review when evaluating plant policies and procedures. Other
reference materials relating to operations that should be available to the
operator include manufacturers' literature, publications by professional
organizations (e.g., the Water Pollution Control Federation), and EPA
publications.
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Chapter Four Facility Site Review
Staffing
Even the best engineered facility cannot perform to its potential without a
capable and qualified staff. The inspector must consider the abilities and
limitations of the operating staff. Staff interviews may include the
individual in charge of overall operation, the chief operator, specific
unit process operators, and laboratory staff.
Management Controls
Monitoring practices are a good indication of both the emphasis placed on
operations and the operator's understanding of process controls. Factors
affecting a facility's monitoring capabilities are:
• The sampling program;
• Performance testing;
• Analytical capabilities; and
• Recordkeeping practices.
An effective process control program is essential to a treatment facility's
optimal performance. However, process control cannot be easily quantified
by the inspector. In most cases, the inspector must rely on discussions
with the plant superintendent and/or operators to supplement available
records and the technical evaluation. The key considerations for effective
process controls are:
• Process knowledge of the operators;
• The basis for the control practices;
• Past performance;
• Operator emphasis on controls; and
• Recordkeeping.
Maintenance Evaluation
Facility maintenance directly affects the ability of the facility to run
efficiently and to remain in compliance with its NPDES permit. There are
two types of facility maintenance:
• Preventive Maintenance
reduces facility operating costs by eliminating breakdowns and
the need for corrective maintenance;
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Chapter Four Facility Site Review
- improves the facility's reliability by minimizing the time
equipment is out of service;
- increases the useful life of equipment, thus avoiding costly
premature replacement;
- avoids possible compliance violations;
• Corrective Maintenance
gets malfunctioning equipment back into operation; and
avoids or minimizes possible compliance violations.
The evaluation of the maintenance function must focus on the ability to
maintain the following: process equipment, vehicles, and buildings and
grounds.
Although each of the five evaluation topics (policy and procedures, organi-
zation, staffing, planning, and management controls) must be covered for
each facility inspected, the following are three common areas of concern in
the maintenance function:
• Staffing and training;
• Planning and scheduling; and
• Management control—records systems and inventory control.
Only well-trained, competent plant staff can be expected to perform ade
quate physical inspections, repairs, and preventive maintenance. Waste
water facility maintenance is complex and requires a variety of skills.
Because many of these skills are not readily available, an ongoing training
program is essential.
Maintenance planning and scheduling is essential to effective corrective
and preventive maintenance. The maintenance supervisor must prepare work
schedules listing job priorities, work assignments, available personnel,
and timing.
A detailed records system is the basis of any maintenance program.
Records are used to establish maintenance histories on equipment, diagnose
problems, and anticipate—and thereby avoid—equipment failure, making them
effective tools for preventive maintenance.
A central inventory for spare parts, equipment, and supplies must be
maintained and controlled. The basis for the inventory should be the
equipment manufacturer's recommendations, supplemented by specific,
historical experience with maintenance problems and requirements.
Inventoried supplies must be kept at levels sufficient to avoid process
interruptions.
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Chapter Four Facility Site Review
A maintenance cost control system should be an integral part of every
wastewater facility. Budgets must be developed from past cost records and
are usually categorized according to preventive maintenance, corrective
maintenance, and major repair requirements, both projected and actual.
Costs over a given year must be compared to the budget on a periodic basis
to control maintenance expenditures. Evaluating costs in this manner
provides both control over expenditures and a basis for development of
future budgets.
The basic concerns that need to be addressed and evaluated during the
inspector's maintenance program review are presented in Table 4-1 (at the
end of this chapter).
NPDES Inspection Manual 4-15 June 1984
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Chapter Four Facility Site Review
References
U.S. Environmental Protection Agency. 1982. Comprehensive Diagnostic
Evaluation and Selected Management Issues. EPA 430/9-82-003.
U.S. Environmental Protection Agency. 1979. Inspector's Guide for
Evaluation of Municipal Wastewater Treatment Plants. EPA 430/9-79-010.
U.S. Environmental Protection Agency. 1978. Field Manual for Performance
Evaluation and Troubleshooting at Municipal Wastewater Treatment
Facilities. MO #16, EPA 430/9/78-001.
U.S. Environmental Protection Agency. 1973. Maintenance Management
Systems for Municipal Wastewater Facilities. EPA 430/9-74-004.
Water Pollution Control Federation (WPCF). 1977. Operation of Wastewater
Treatment Plants. MOP No. 11, WPCF, 1977.
NPDES Inspection Manual 4-16 June 1984
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Chapter Four Facility Site Review
Table 4-1
Operations and Maintenance Functions Evaluation Questions
POLICIES AND PROCEDURES
• Is there a formal or informal set of policies for facility
operations?
• Do policies address?
- Remaining in Compliance
- Maintaining Process and Cost Controls
- Quality control
Preventative maintenance
• Is there a set of standard procedures to implement these
policies?
• Are they written or informal?
• Do the procedures consider the following areas?
- Safety - Collection System
- Emergency - Pumping Stations
- Laboratory - Treatment Process
- Process Control - Sludge Disposal
- Operating Procedures - Equipment Record System
- Monitoring - Maintenance Planning and
- Labor Relations Scheduling
- Energy Conservation - Work Orders
- Inventory Management
• Are the procedures followed in fact?
ORGANIZATION
• Is there an Organizational Plan (or Chart) for operations?
• Does the Plan include?
- Delegation of responsibility and authority
- Job descriptions
- Interaction with other functions (such as maintenance)
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Chapter Four Facility Site Review
• Is the Organizational Plan formal or informal?
• Is the Organizational Plan available to and understood by the
staff?
• Is the Organizational Plan followed in fact?
• Is the Organizational Plan consistent with policies and
procedures?
• Is the Organizational Plan flexible? Can it handle emergency
situations?
• Does the Organizational Plan clearly define lines of authority
and responsibility in such subfunctional areas as?
- Laboratory - Mechanical
- Process Control - Electrical
- Equipment Operation - Instrumentation
- Instrumentation - Buildings and Grounds
Sludge Disposal - Automotive
- Collection System - Supplies and Spare Parts
- Pump Stations
- Monitoring Practices
STAFFING
• Is there an adequate number of staff persons to achieve policies
and procedures?
• Are staff members adequately qualified for their duties and
responsibilities?
- Certification
- Qualifications
- Ability
- Job performance
- Understanding of treatment processes
• Is staff effectively utilized?
• Has the potential for borrowing personnel been considered?
• Are training procedures followed for?
- Orientation of new staff
- Training new operators
- Training new supervisors
- Continuing -training of existing staff
Cross training
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Chapter Four Facility Site Review
• What training procedures are used?
Formal classroom
Home study
On-the-job training
- Participation in professional organization
Text and manuals
• Does the training program provide specific instruction for the
various operations and maintenance activities?
Safety - Handling emergencies
- Laboratory procedures - Mechanical
- Treatment processes - Electrical
- Instrumentation - Automotive
- Equipment trouble-shooting - Building maintenance
- Handling personnel problems - Inventory control
- Monitoring practices
• Does management encourage staff motivation?
• Does management support its first-line supervisors?
• How is staff motivation maintained?
- Encouragement for training
- Job recognition
- Promotional opportunities
Salary incentives
- Job security
- Working environment
PLANNING (OPERATIONS)
• How are operating schedules established?
• Do schedules attempt to attain optimum staff utilization?
• Are line supervisors included in manpower scheduling?
• Are staff involved in/informed of manpower planning?
• Is there sufficient long-term planning for staff replacement
and system changes?
• Are there procedures in manpower staffing for emergency
situations?
• How are process control changes initiated?
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Chapter Four Facility Site Review
• How do process control changes Interact with management
controls?
• How effectively are laboratory results used in process control?
• Are there emergency plans for treatment control?
• Is there an effective energy management plan? Is the plan
utilized?
• To what extent are operations personnel involved in the
budgetary process?
• Do budgets adequately identify and justify the cost components
of operations?
• Are future budgets based on current and anticipated operating
conditions?
• Do operating and capital budget limits constrain operations
(capital replacement and improvements)?
• Can budget line items be adjusted to reflect actual operating
conditions?
PLANNING (MAINTENANCE)
• Are maintenance activities planned? Formally or informally?
• Does the facility have sufficient management controls to affect
realistic planning and scheduling? If the controls exist are
they utilized?
• To what extent do the other facility functions become involved
in the planning process?
• Are operating variables exploited to simplify maintenance
efforts?
• Is efficient staff utilization a significant factor in
planning?
• To what extent is the supplies and spare parts inventory
planned in conjunction with maintenance activities?
• Have minimum and maximum levels been established for all
inventory items?
• Does maintenance have an emergency plan in harmony with the
utility emergency plan?
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Chapter Four Facility Site Review
• Is plan up to date? Is the staff knowledgeable about emergency
procedures?
• Does a plan exist for returning to the preventive maintenance
mode following an emergency?
• Are preventive maintenance tasks scheduled in accordance with
manufacturer's recommendations?
• Is adequate time allowed for corrective maintenance?
• Are basic maintenance practices (preventive and corrective)
and frequencies reviewed for cost-effectiveness?
• Do the management controls provide sufficient information for
accurate budget preparation?
• Does the maintenance department receive feedback on cost
performance to facilitate future budget preparation?
• To what extent are maintenance personnel involved in the
budgetary process?
• Do the management controls provide sufficient information for
accurate budget preparation?
• Do budgets adequately identify and justify the cost components
of maintenance?
• Are future budgets based on current and anticipated operating
and maintenance conditions?
• Do maintenance and capital budget limits constrain preventive
maintenance (equipment replacement and improvements)?
• Does the maintenance department receive adequate feedback on
cost performance?
• Can budget line items be adjusted to reflect actual main-
tenance conditions?
MANAGEMENT CONTROLS (OPERATIONS)
• Are the following documents maintained in a current state?
- Operating Reports
- Work Schedules
- Activity Reports
- Performance Reports (labor, supplies, energy)
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Chapter Four Facility Site Review
- Expenditure Reports (labor, supplies, energy)
- Cost Analysis Reports
- Emergency and Complaint Calls
- Process Control Data Including Effluent Quality
• Do the reports contain sufficient information to support their
intended purpose?
• Are they usable and accepted by the staff?
• Are reports being completed as required?
• Are reports consistent with one another?
• Are reports used directly in process control?
• Are the reports reviewed and discussed with operating staff?
• What type of summary reports are required?
• To whom are reports distributed and when?
MANAGEMENT CONTROLS (MAINTENANCE)
• Does a maintenance record system exist? Does it include?
- As-built drawings
- Shop drawings
- Construction specifications
- Capital and equipment inventory
- Maintenance history (preventive and corrective)
- Maintenance costs
• Is the base record system kept up to date as part of daily
maintenance practices?
• Is there a work order system for scheduling maintenance? Is
it explicit or implicit?
• Do work orders contain?
- Date
- Work order number
- Location
- Nature of problem
- Work required
- Time requirements
- Assigned personnel
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Chapter Four Facility Site Review
- Space for reporting work performed, required supplies,
time required, and cost summary
- Responsible staff member and supervisory signature
requirements
• When emergency work must be performed without a work order, is
one completed afterwards?
• Are work orders usable and acceptable by staff as essential to
the maintenance program? Are they actually completed?
• Is work order information transferred to a maintenance record
system?
• Does a catalog or index system exist for controlling items in
inventory?
• Are withdrawal tickets used for obtaining supplies from
inventory?
• Do the tickets contain cost information and interact well with
inventory controls and the work order system?
• Is the cost and activity information from work orders
aggregated to provide management reports? Is this information
also used for budget preparation?
• Is maintenance performance discussed regularly with the staff?
• How is the cost of contract maintenance or the use of
specialized assistance recorded?
• Are there adequate safeguards and penalties to prevent
maintenance cards from being returned without the work being
done?
• Is the preventive maintenance record checked after an
emergency equipment failure?
NPDES Inspection Manual 4-23 June 1984
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Facility Site Review Ctecklist
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1. Standby power or other equivalent provision is provided.
2. Adequate alarm system for power or equipment failures is available.
3. POTW handles and disposes of sludge according to applicable Federal, State, and
and local regulations.
4. All treatment units, other than back-up units, are in service.
5. Procedures for facility operation and maintenance exist.
6. Organization plan (chart) for operation and maintenance is provided.
7. Operating schedules are established.
8. Emergency plan for treatment control is established.
9. Operating management control documents are current and include:
a. Operating report
b. Work schedule
c. Activity report (time cards)
10. Maintenance record system exists and includes:
a. As-built drawings
b. Shop drawings
c. Construction specifications
d. Maintenance history
e. Maintenance costs
11. Adequate number of qualified operators are on-hand.
12. Established procedures are available for training new operators.
13. Adequate spare parts and supplies inventory and major equipment specifications
are maintained.
14. Instruction files are kept for operation and maintenance of each item of major
equipment.
15. Operation and maintenance manual is available.
16. Regulatory agency was notified of by-passing.
(Dates )
4-24
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Facility Site Beview Checklist
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
17. Hydraulic and/or organic overloads are experienced.
Reasons for overloads
18. Up-to-date
19. Dated tags
equipment repair records are maintained.
show out of service equipment.
20. Routine and preventive maintenance are scheduled/performed on time.
4-25
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Chapter Five
Sampling
Contents Pa8e
1 Evaluation of Permittee Sampling Program 5-1
Objectives and Requirements 5-1
Evaluation of Permittee Sampling Procedures 5-2
Sample Collection Techniques 5-2
Types of Samples 5-2
Sample Containers 5-3
Sample Identification 5-4
Sample Preservation and Holding Time 5-4
Quality Control 5-4
2 Inspector's Compliance Sampling 5-7
Objectives and Requirements 5-7
Sample Collection 5-7
Selection of Representative Sampling Sites 5-7
Sampling Techniques 5-8
Sample Volume 5-8
Selection and Preparation of Sample Containers 5-9
Preservation Method and Holding Time 5-9
Sample Identification Methods 5-9
Transfer of Custody and Shipment 5-10
Quality Control 5-10
Data Handling and Reporting 5-11
References 5-21
Permittee Sampling Inspection Checklist 5-22
List of Tables
5-1 Compositing Methods 5-12
5-2 Recommended Containers, Preservation Techniques,
and Holding Times 5-14
NPDES Inspection Manual 5-i June 1984
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Saapling
Chapter Five
1 Evaluation of
Permittee Sampling Program
Wastewater sampling/analysis is an integral part of the NPDES Compliance
Monitoring Program. NPDES permits contain specific and legally enforceable
effluent limitations and self-monitoring requirements for effluent
sampling/analysis and flow measurement. The sampling frequency, the sample
type, the parameters to be monitored, the parameter limitations, the
analytical methods, and the reporting frequency are determined by the
permitting agency.
Objectives and Requirements
In an evaluation of the permittee sampling program the inspector should set
the following objectives:
• Verification that permittee's sampling program is in compliance
with permit;
• Verification that sampling program complies with 40 CFR 136; and
• Support of enforcement action.
Requirements for sampling, analysis, preservation techniques, sample
holding times, and sample containers are given under 40 CFR 136 as
authorized by Section 304(h) of the Clean Water Act. 40 CFR 136 superceded
any method or techniques specified in the manual. More information on
required analytical procedures can be found under "Evaluation of Permittee
Laboratory Analytical Procedures" in Chapter Eight.
A Permittee Sampling Inspection Checklist for the inspector's use appears
at the end of this chapter.
NPDES Inspection Manual 5-1 June 1984
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Chapter Five Sampling
Evaluation of Permittee Sampling Procedures
An evaluation of the permittee sampling program should include an
inspection of sampling procedures used by the facility and of quality
control measures used to ensure the integrity of sample data. Evaluation
of sampling procedures should include an assessment of the following five
areas:
(1) Sample Collection Techniques
Depending on the objectives or requirements of the monitoring program,
samples can be collected either manually or with automatic samplers.
The following general guidelines apply when taking samples:
• Take samples at a site specified in the NPDES permit and/or at a
site selected to yield a representative sample.
• Use the approved sample method (grab, composite, automatic sampler)
as required in the sampling and analysis methods of 40 CFR 136.
Some parameters that are not to be sampled by automatic samplers or
compositing include the following: dissolved oxygen, total
residual chlorine, pH, temperature, oil and grease, fecal coliform,
and purgeable organics.
• Exclude large nonhomogeneous particles and objects.
• Collect the sample facing upstream to avoid contamination.
• Do not rinse sample container with sample when collecting microbio-
logical samples, but fill it directly to within 2.5 to 5 cm from
the top.
• Fill the container completely if the sample is to be analyzed for
purgeable organics, oxygen, ammonia, hydrogen sulfide, free chlo-
rine, pH, hardness, sulfite, ammonium, ferrous iron, acidity, or
alkalinity.
• Collect sufficient volume to allow for quality assurance testing.
(2) Types of Samples
Two types of sampling techniques are used: grab and composite.
Grab Samples. Grab samples are individual samples collected over a
period of time not exceeding 15 minutes; the grab sample can be taken
manually. The collection of a grab sample is appropriate when a sam-
ple is needed to:
Inspection Manual 5^Z June 1984
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Chapter Five Sanpling
• Provide information about instantaneous concentrations of pollutant
at specific time;
• Allow collection of a variable sample volume;
• Corroborate composite samples; and
• Collect samples for parameters not amenable to automatic sampling
(e.g., oil and grease, coliform bacteria).
Composite Samples. These samples consist of grab samples collected at
equal intervals and combined proportional to flow, a sample contin-
uously collected proportionally to flow, or equal volumes taken at
varying time intervals. Composite samples are used when stipulated in
a permit and when:
• Determining average pollutant concentration during the compositing
period;
• Calculating mass/unit time loadings; and
• Wastewater characteristics are highly variable.
There are six methods for compositing samples; they may be collected
using either manual or automatic sampling. The six compositing
methods, all of which depend on either a continuous or periodic
sampling, are shown in Table 5-1. In any manual compositing method,
sample manipulation should be minimized to reduce the possibility of
contamination.
Others. Special collection methods are generally required for
purgeable organics and microbiological samples because of their unique
nature. These samples are usually collected manually.
(3) Sample Containers
An accurate description of the required sample containers, sample
container preparation, and sample collection techniques is presented
in 40 CFR 136.
It is essential that the sample containers be made of chemically
resistant material and do not affect the concentrations of the
pollutants to be measured. In addition, sample containers must have a
closure that will protect the sample from contamination.
Wastewater samples for chemical analysis are generally collected in
plastic (polyethylene) containers. Exceptions to this general rule
NPDES Inspection Manual ~~5r3 June 1984
-------
Chapter Five Sampling
are oil and grease samples, pesticides, PCBs, and other organic pollu-
tant samples. These are collected in properly rinsed glass jars or
bottles and sealed. Bacteriological samples are generally collected
in properly sterilized plastic or glass containers.
(4) Sample Identification
Each sample must be accurately and completely identified. It is im-
portant that any label used to identify the sample be moisture-
resistant and able to withstand field conditions. A numbered label
associated with a field data sheet containing detailed information on
the sample may be preferable to using only a label for information.
(5) Sample Preservation and Holding Time
In most cases, wastewater samples contain one or more unstable
pollutants that require immediate analysis or preservation. Prompt
analysis is the most positive assurance against error from sample
deterioration, but this is not feasible for composite samples, in
which portions may be stored for as long as 24 hours. It is important
that preservation of the samples be provided for during compositing,
where possible, in addition to being preserved before being
transferred to the laboratory. Procedures used to preserve samples
include refrigeration, pH adjustment, and chemical treatment. Proper
preservation and holding time for samples is essential to the
integrity of the monitoring program. (See Table 5-2 and refer to
40 CFR 136.)
Quality Control
Control checks should be performed during the actual sample collection to
determine the performance of the sample collection system. In general, the
most common monitoring errors are usually caused by improper sampling,
improper preservation, inadequate mixing during compositing and splitting,
and excessive sample holding time. The following samples should be used to
check the sample collection system: ~
Duplicate Samples. These are separate samples taken from the same
source at the same time. These provide a check on sampling
equipment and precision techniques.
Split Samples. This is a sample that has been divided into two
containers for analysis by separate laboratories. These aid in
identifying discrepancies in the permittee's analytical techniques
and procedures.
Spike Samples. This is a sample to which a known quantity of the
same substance has been added. These provide a proficiency check
for accuracy of the analytical procedures.
NPDES Inspection Manual 5-4 June 1984
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Chapter Five Sampling
• Sample Preservative Blanks. This is a sample of distilled water to
which a known quantity of preservative is added. This sample is
then analyzed to determine the efficacy of the preservative. These
provide a check on the contamination of chemical preservatives.
NPDES Inspection Manual tt June 1984
-------
Chapter Five
2 Inspector's Compliance Sampling
Objectives and Requirements
Specific objectives of the sampling conducted by inspectors include the
following:
• Verification of compliance with effluent limitations;
• Verification of self-monitoring data;
• Support of enforcement action; and
• Support of permit reissuance and/or revision.
It must be stressed that the laboratory that will analyze the samples must
be notified far enough in advance of the inspection to avoid analysis
scheduling problems.
Sample Collection
Sample collection is an important part of the compliance monitoring pro-
gram. Without proper sampling procedures, the results of such monitoring
programs are neither useful nor valid, even with the most precise and
accurate analytical measurement.
Selection of Representative Sampling Sites
Samples should be collected at the location specified in the permit. In
some instances, the sampling location specified in the permit or the loca-
tion chosen by the permittee may not be adequate for the collection of a
representative sample. In that case the inspector should choose the most
representative sampling point available.
NPDE3 Inspection Manual 5=7 Jane 1984
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Chapter Five Sampling
Influent Samples. These should be taken at points of high-turbulence flow
to ensure good mixing. In some instances, the most desirable location may
not be accessible. Sampling points should always be above plant return
lines. The preferred sampling points for raw wastewater are:
• The upflow siphon following the comminutor (in absence of grit
chamber);
• The upflow distribution box following pumping from the main plant
wet well;
• Aerated grit chamber;
• Flume throat; and
• Pump wet well (if turbulent).
Effluent Samples. These should be collected at the site specified in the
permit or, if no site is specified in the permit, at the most representa-
tive site downstream from all entering waste streams prior to entry into
the receiving waters. Samples should be collected after chlorination.
This will require dechlorination and reseeding for the BODs analysis. It
may occasionally be desirable to sample before chlorination if it is felt
that the simplified laboratory procedures will result in better
results.
Sampling Techniques
Both grab and composite samples can be collected either manually or with
automatic samplers. A composite sample should consist of a minimum of
eight grab samples collected at equal intervals and combined proportional
to flow, or a sample continuously collected proportionally to flow. More
than the minimum number of discrete samples may be required where the
wastewater loading is highly variable. In any manual compositing method,
sample manipulation should be minimized to reduce the possibility of con-
tamination. Variability in waste stream flow rate and parameter concen-
tration should be carefully considered when choosing compositing methods.
Although eight samples is the recommended number for a composite sample,
the number specified in the permit or in other applicable standards should
be used if it differs from the recommended number.
Sample Volume
The volume of samples collected depends on the type and number of analyses
that are needed, as reflected in the parameters to be measured. The volume
of the sample obtained should be sufficient to perform all the required
analyses plus an additional amount to provide for any split samples or re-
peat analyses. The laboratory receiving the sample should be consulted for
any specific volume required. A breakdown of the recommended minimum
NPDES Inspection Manual 5^-8 June 1984
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Chapter Five Saapling
sample volumes for different pollutant parameters can be found in EPA's
"Methods for Chemical Analysis of Water and Wastes," 1979; "Handbook for
Sampling and Sample Preservation of Water and Wastewater," 1982; and the
current, EPA approved edition of "Standard Methods."
Selection and Preparation of Sample Containers
The selection and preparation of sample containers will be based on the
parameters to be measured. A detailed description of selection and prepa-
ration of sample containers for different pollutant parameters is included
in the current, approved edition of "Standard Methods," and in EPA's
"Handbook for Sampling and Sample Preservation of Water and Wastewater,"
1982.
Preservation Method and Holding Time
Prompt analysis is the best insurance against error caused by sample
deterioration, but this is not always possible. Table 5-2 shows the recom-
mended preservation method and maximum holding time for different para-
meters. It is important that preservation of samples be provided for
during compositing (icing is the most commonly used method), where possi-
ble, in addition to preservation of the composited sample before transit to
the analytical laboratory.
Sample Identification Methods
Each sample must be accurately and completely identified. It is important
that any label used to identify the sample be moisture-resistant and able
to withstand field conditions. A numbered label associated with a field
data sheet containing detailed information on the sample may be preferable
to using only a label for information. The information provided for each
sample should include the following:
• Sample site location, discharge, and facility;
• Name of collector(s);
• Date and time of collection;
• Indication of grab or composite sample with appropriate time and
volume information;
• Identification of parameter to be analyzed;
• Preservative used;
• Indication of any unusual condition at the sampling location and/or
in the appearance of the Wastewater; and
NPDES Inspection Manual 5P5 June 1984
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Chapter Five Sampling
Notation of conditions such as pH, temperature, residual chlorine,
and appearance that may change before the laboratory analysis,
including the identification number of instruments used to measure
parameters in the field.
Transfer of Custody and Shipment
In order to ensure the validity of the permit compliance sampling data in
court, there must be accurate written records tracing the custody of each
sample through all phases of the monitoring program. The primary objective
of this chain-of-custody is to create an accurate written record that can
be used to trace the possession and handling of the sample from the moment
of its collection through analysis and introduction as evidence.
• When transferring possession of samples, the transferee must sign
and record the date and time on the Chain-of-Custody Record (use
currently approved Chain-of-Custody Record). In general, custody
transfers are made on each individual sample, although samples may
be transferred as a group, if desired. Every person who takes
custody must fill in the appropriate section of the Chain-of-
Custody Record. The number of transfers should be kept to a
minimum.
• The person taking the sample is responsible for properly packing
and dispatching the samples to the appropriate laboratory for
analysis. This responsibility includes filling out, dating, and
signing the appropriate portion of the Chain-of-Custody Record.
• All packages sent to the laboratory must be accompanied by the,
Chain-of-Custody Record and other pertinent forms. A copy of these
forms should be retained by the originating office.
• Mailed packages should be sent with return receipt requested. If
sent by common carrier, receipts are retained as part of the
permanent chain-of-custody documentation.
• Shipped samples should be properly packed to prevent breakage, and
the package sealed or locked so that any evidence of tampering may
be readily detected.
Quality Control
The objectives of quality control are to obtain reproducible and consistent
sampling results, and to produce complete, precise, accurate, and represen-
tative data. Refer to page 5-4 for quality control procedures for checking
the sample collection system.
NPDES Inspection Manual 5-10 June 1984
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Chapter Five Sampling
Data Handling and Reporting
To obtain meaningful data for the compliance monitoring program, a properly
preserved representative sample must be delivered for analysis. The analy-
sis must be performed in the prescribed fashion according to EPA approved
procedures. The calculations should be completed and the results converted
to final form so that the analytical data can be permanently recorded in
meaningful, exact terms.
The analytical information reported should include the measured parameters
and the details of the analysis, such as original analytical instrumenta-
tion readings, correction factors, blanks, and the reported data values.
The compliance monitoring records should include sampling date, time and
location, analyses dates and time, names of analysts, analytical methods/
techniques used, and analytical results. To ensure that data resulting
from various analyses are recorded, transferred, and stored correctly, the
data should be checked at the various transfer points.
NPDES Inspection Manual IFTIJune 1984
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Chapter Five
Sampling
Table 5-1
COMPOSITING METHODS
Compositing
Principle
Advantages
Disadvantages
Comments
Constant sample
volume, constant
time interval
between samples
Constant sample
volume, time
interval between
samples
proportional to
stream flow
Constant time
interval between
samples, sample
volume proportional
to total stream
flow at time of
sampling
Minimal instrumen-
tation and manual
effort; requires
no flow measure-
ment
Minimal manual
effort
Minimal
instrumentation
Constant time
interval between
samples, sample
volume proportional
to total stream
flow since last
sample
Minimal
instrumentation
May lack represen-
tativeness espe-
cially for highly
variable flows
Requires accurate
flow measurement/
reading equipment;
manual compositing
from flow chart
Manual compositing
from flow chart in
absence of prior
information on the
ratio of minimum to
maximum flow;
chance of collec-
ting too small or
too large indivi-
dual discrete
samples for a
given composite
volume
Manual compositing
from flow chart in
absence of prior
information on the
ratio of minimum to
maximum flow;
chance of collec-
ting either too
small or too large
individual dis-
crete samples for
a given composite
volume
Widely used in
both automatic
samplers and
manual sampling
Widely used in
automatic as well
as manual sampling
Used in automatic
samplers and
widely used as
manual method
Not widely used in
automatic samplers
but may be done
manually
NPDES Inspection Manual
June 1984
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Chapter Five
Saapling
Table 5-1
COMPOSITING METHODS (Continued)
Compositing
Principle
Advantages
Disadvantages
Comments
Constant pumping
rate
Sample pumping rate
proportional to
stream flow
Minimal manual
effort, requires
no flow
measurement
Most representa-
tive especially
for highly
variable flows;
minimal manual
effort
Requires large
sample capacity;
may lack represen-
tativeness for
highly variable
flows
Requires accurate
flow measurement
equipment, large
sample volume,
variable pumping
capacity, and
power
Practical but not
widely used
Not widely used
NPDES Inspection Manual
June 1984
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Chapter Five
Sampling
Table 5-2
RECOMMENDED* CONTAINERS, PRESERVATION TECHNIQUES, AND HOLDING TIMES
Parameter
Bacterial Tests
Coliform, fecal
and total
Fecal streptococci
Inorganic Tests
Acidity
Alkalinity
Ammonia
Biochemical oxygen
demand
Biochemical oxygen
demand,
carbonaceous
Bromide
Chemical oxygen
demand
Chloride
Chlorine, total
residual
Color
Cyanide, total and
amenable to chlori-
nation
Fluoride
Hardness
Container^)
P,G
P,G
P.G
P,G
P,G
P,G
P.G
P,G
P,G
P,G
P,G
P,G
P,G
P
P,G
Preservative(2), (3)
Cool, 4°C
0.008% N32S203 (5)
Cool, 4°C
0.008% Na2S203 (-*)
Cool, 4°C
Cool, 4°C
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
Cool, 4°C
None required
Cool, 4°C
H2S04 to pH<2
None required
None required
Cool, 4°C
Cool, 4°C
NaOH to pH>12
0.6g ascorbic
acid (5)
None required
HN03 or H2S04 to pH<2
Maximum
Holding Time(4)
6 hours
6 hours
14 days
14 days
28 days
48 hours
48 hours
28 days
28 days
28 days
Analyze immediately
48 hours
14 days(6)
28 days
6 months
June 1984
NPDES Inspection Manual
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Chapter Five
Sampling
Table 5-2
RECOMMENDED* CONTAINERS, PRESERVATION TECHNIQUES, AND HOLDING TIMES
(Continued)
Parameter
Hydrogen ion (pH)
Kjeldahl and organic
Nitrogen
Metals (7)
Chromium VI
Mercury
Metals, except
Chromium VI and
Mercury
Nitrate
Nitrate-nitrite
Nitrite
Oil and grease
Organic carbon
Orthophosphate
Dissolved oxygen,
Probe
Dissolved oxygen,
Winkler method
Phenols
Phosphorus
(elemental)
Container(l)
P,G
P,G
P,G
P,G
P.G
P,G
P,G
P,G
G, (wide
mouth, tef-
lon lined
cap recom-
mended)
P,G
P,G
G bottle
and top
G bottle
and top
G only
G
Preservative^), (3)
None required
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
HN03 to pH<2
HN03 to pH<2
Cool, 4°C
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
HC1 or H2S04 to pH<2
Filter immediately
Cool, 4°C
None required
Fix on site and
store in dark
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
Maximum
Holding Time(4)
Analyze immediately
28 days
24 hours
28 days
6 months
48 hours
28 days
48 hours
28 days
28 days
48 hours
Analyze immediately
8 hours
28 days
48 hours
NPDES Inspection Manual
June 1984
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Chapter Five
Sampling
Table 5-2
RECOMMENDED* CONTAINERS, PRESERVATION TECHNIQUES, AND HOLDING TIMES
(Continued)
Parameter
Phosphorus, total
Residue, total
Residue, filterable
Residue, non-
filterable (TSS)
Residue, settleable
Residue, volatile
Silica
Specific conductance
Sulfate
Sulfide
Sulflte
Surfactants
Temperature
Turbidity
Organic Tests(^)
Purgeable
halocarbons
ContainerC1)
P,G
P,G
P,G
P,G
P,G
P,G
P
P,G
P,G
P,G
P,G
P,G
P,G
P,G
G, Teflon-
lined
septum
Preservative(2) , (3)
Cool, 4°C
H2S04 to pH<2
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C
Cool, 4°C, add
zinc acetate plus
sodium hydroxide
to pH>9
None required
Cool, 4°C
None required
Cool, 4°C
Cool, 4°C
0.008% Na2S203 (^)
Maximum
Holding Time(4)
28 days
7 days
48 hours
7 days
48 hours
7 days
28 days
28 days
28 days
7 days
Analyze immediately
48 hours
Analyze immediately
48 hours
14 days
NPDES Inspection Manual
5-16
June 1984
-------
Chapter Five
Sampling
Table 5-2
RECOMMENDED* CONTAINERS, PRESERVATION TECHNIQUES, AND HOLDING TIMES
(Continued)
Parameter
Purgeable aromatic
hydrocarbons
Acrolein and
acrylonitrile
Phenols (n)
Benzidines (H)
Phthalate esters (H)
Nitrosamines (H, I4)
PCBs (11)
acrylonitrile
Nitroaromatics and
isophorone (H)
Polynuclear aromatic
hydrocarbons (H)
Haloethers C11)
Container(l)
G, Teflon-
lined
s ep turn
G, Teflon-
lined
septum
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
Preservative^) , (3)
Cool, 4°C
0.008% Na2S203 (5)
HC1 to PH<2 (9)
Cool, 4°C
0.008% Na2S203 (5)
Adjust pH to 4-5 (10)
Cool, 4°C
0.008% Na2S203 (5)
Cool, 4°C
0.008% Na2S203(5,12)
Cool, 4°C
Cool, 4°C
store in dark
0.008% Na2S203
Cool, 4°C
Cool, 4°C
store in dark
0.008% Na2S203 (5)
Cool, 4°C
0.008% Na2S203 (^)
store in dark
Cool, 4°C
0.008% Na2S203 (5)
Maximum
Holding Time(4)
14 days
14 days
7 days until
extraction, 40 days
after extraction
7 days until
extraction (13)
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
NPDES Inspection Manual
June 1984
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Chapter Five
Sampling
Table 5-2
RECOMMENDED* CONTAINERS, PRESERVATION TECHNIQUES, AND HOLDING TIMES
(Continued)
Parameter
Chlorinated
hydrocarbons (H)
TCDD (11)
Pesticides Tests
Pesticides (H)
Radiological Tests
Alpha, beta and
radium
Container(l)
G, Teflon-
lined cap
G, Teflon-
lined cap
G, Teflon-
lined cap
P,G
Preservative(2) , (3)
Cool, 4°C
Cool, 4°C
0.008% Na2S203 (5)
Cool, 4°C
PH 5-9 (15)
HN03 to PH<2
Maximum
Holding Time(4)
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
7 days until
extraction, 40 days
after extraction
6 months
* Will become mandatory when promulgated under 40 CFR 136.
June 1984
NPDES Inspection Manual
5-18
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Chapter Five Sampling
TABLE 5-2 NOTES
(1) Polyethylene (P) or Glass (G).
(2) Sample preservation should be performed immediately upon sample
collection. For composite chemical samples, each aliquot should be
preserved at the time of collection. When use of an automated sampler
makes it impossible to preserve each aliquot, then chemical samples
may be preserved by maintaining at 4°C until compositing and sample
splitting is completed.
(3) When any sample is to be shipped by common carrier or sent through the
United States Mails, it must comply with the Department of
Transportation Hazardous Materials Regulations (49 CFR Part 172). The
person offering such material for transportation is responsible for
ensuring such compliance. For the preservation requirements of
Table 5-2, the Office of Hazardous Materials, Materials Transportation
Bureau, Department of Transportation has determined that the Hazardous
Materials Regulations do not apply to the following materials:
Hydrochloric acid (HCl) in water solutions at concentrations of 0.04%
by weight or less (pH about 1.96 or greater); Nitric acid (HN03) in
water solutions at concentration of 0.15% by weight or less (pH about
1.62 or greater); Sulfuric acid (H2S04) in water solutions at
concentrations of 0.35% by weight or less (pH about 1.15 or greater);
and Sodium hydroxide (NaOH) in water solutions at concentrations of
0.080% by weight or less (pH about 12.30 or less).
(4) Samples should be analyzed as soon as possible after collection. The
times listed are the maximum times that samples may be held before
analysis and still be considered valid. Samples may be held for
longer periods only if the permittee, or monitoring laboratory, has
data on file to show that the specific types of samples under study
are stable for the longer time, and has received a variance from the
Regional Administrator under §136.3 (e). Some samples may not be
stable for the maximum time period given in the table. A permittee or
monitoring laboratory is obligated to hold the sample for a shorter
time if knowledge exists to show this is necessary to maintain sample
stability. See §136.3 (e) for details.
(5) Should only be used in the presence of residual chlorine.
(6) Maximum holding time is 24 hours when sulfide is present. Optionally
all samples may be tested with lead acetate paper before pH
adjustments in prder to determine if sulfide is present. If sulfide
is present, it can be removed by the addition of cadmium nitrate
powder until a negative spot test is obtained. The sample is filtered
and then NaOH is added to pH 12.
(7) Samples should be filtered immediately on-site before adding
preservation for dissolved metals.
NPDES Inspection Manual5-19June 1984
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Chapter Five Sampling
TABLE 5-2 NOTES
(8) Guidance applies to samples to be analyzed by GC, LC, or GC/MS for
specific compounds.
(9) Sample receiving no pH adjustment must be analyzed within 7 days of
sampling.
(10) The pH adjustment is not required if acrolein will not be measured.
Samples for acrolein receiving no pH adjustment must be analyzed
within 3 days of sampling.
(11) When the extractable analytes of concern fall within a single chemical
category, the specified preservative and maximum holding times should
be observed for optimum safeguard of sample integrity. When the
analytes of concern fall within two or more chemical categories, the
sample may be preserved by cooling to 4°C, reducing residual chlorine
with 0.008% sodium thiosulfate, storing in the dark, and adjusting the
pH to 6-9; samples preserved in this manner may be held for seven days
before extraction and for forty days after extraction. Exceptions to
this optional preservation and holding time procedure are noted in
footnote 5 (re the requirement for thiosulfate reduction of residual
chlorine), and footnotes 12, 13 (re the analysis of benzidine).
(12) If 1,2-diphenylhydrazine is likely to be present, adjust the pH of the
sample to 4.0 +_ 0.2 to prevent rearrangement to benzidine.
(13) Extracts may be stored up to 7 days before analysis if storage is
conducted under an inert (oxidant-free) atmosphere.
(14) For the analysis of diphenylnitrosamine, add 0.008% Na2S203 and adjust
pH to 7-10 with NaOH within 24 hours of sampling.
(15) The pH adjustment may be performed upon receipt at the laboratory and
may be omitted if the samples are extracted within 72 hours of
collection. For the analysis of aldrin, add 0.008% Na2S203-
NPDES Inspection Manual 5-20June 1984
-------
Chapter Five Sampling
References
AWWA, APHA, and WPCF. Standard Methods for the Examination of Water and
Wastewater. Use the most current, accepted edition.
Federal Register. Vol 44. No. 33, Dec. 23, 1979. Guidelines Establishing
Test Procedures for Analysis of Pollutants: Proposed Regulations.
Harris, D.J. and Keffer, W.J. 1974. Wastewater Sampling Methodologies and
Flow Measurement Techniques. U.S. Environmental Protection Agency Region
VII, EPA-907/9-74-005, Kansas City, Missouri.
Lauch, R.P. 1975. Performance of ISCO Model 1391 Water and Wastewater
Sampler. U.S. Environmental Protection Agency, EPA-670/4-75-003,
Cincinnati, Ohio.
Lauch, R.P. 1976. A Survey of Commercially Available Automatic Wastewater
Samplers." U.S. Environmental Protection Agency, EPA-600/4-76-051,
Cincinnati, Ohio.
Shelley, P.E. 1975. Design and Testing of a Prototype Automatic Sewer
Sampling System. Office of Research and Monitoring, U.S. Environmental
Protection Agency, EPA 600/2-76-006, Washington, D.C.
Shelley, P.E., and Kirkpatrick, G.A. 1975. An Assessment of Automatic
Sewer Flow Samples. Office of Research and Monitoring, U.S. Environmental
Protection Agency, EPA-600/2-75-065, Washington, D.C.
U.S. Environmental Protection Agency. 1978. Methods for Benzidine,
Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water
and Wastewater. Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio.
U.S. Environmental Protection Agency. 1979. Methods for Chemical Analysis
of Water and Wastes. EPA-600/4-79-020, Washington, D.C.
U.S. Environmental Protection Agency. 1981. Methods for Organic Chemical
Analysis of Water and Wastes by GC, HPLC and GC/MS. Environmental
Monitoring Support Laboratory, Cincinnati, Ohio.
U.S. Environmental Protection Agency. 1982. Handbook for Sampling and
Sample Preservation of Water and Wastewater. EPA-600/4-82-029,
Cincinnati,Ohio.
Wood, L.B., and Stanbridge, H.H. 1968. "Automatic Samplers," Water
Pollution Control, Vol. 67, No. 5, pp. 495-520.
NPDES Inspection Manual 5-21 June 1984
-------
BemLttee Sampling InspectJop Checklist
A. Permittee Sa^xLiqg Evaluation
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1.
2.
3.
4.
5.
6.
7.
8
Samples are taken at sites specified in permit.
Locations are adequate for representative samples.
Flow proportioned samples are obtained where required by permit.
Sampling and analysis completed on parameters specified by permit.
Sampling and analysis done in frequency specified by permit.
Permittee is using method of sample collection required by permit.
Required Mathod:
If not, method being used is: ( ) Grab ( ) Manual composite ( )
( ) Automatic composite
Sample collection procedures are adequate:
a. Samples refrigerated during compositing
b. Proper preservation techniques used
c. Containers and sample holding times before analyses conform with 40 CFR 136.3
Monitoring and analyses are performed more often than required by permit. If so,
results reported in permittee's self-monitoring report.
B
Inspection Procedures and Observations
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1. Grab samples obtained.
2. Composite sample obtained
Compositing frequency Preservation
3. Sample refrigerated during compositing.
4. Flow proportioned sample obtained.
5. Sample obtained from facility sampling device.
6. Sample representative of volume and nature of discharge.
7. Sample split with permittee.
8. Chain of custody procedures employed.
5-22
-------
Chapter Six
Flow Measurement
Contents Page
1 Evaluation of Permittee's Flow Measurement 6-1
Objectives and Requirements 6-1
Evaluation of Facility Installed Devices 6-1
Evaluation of Permittee Data Handling and Reporting 6-2
Evaluation of Permittee Quality Control 6-3
2 Flow Measurement Compliance 6-5
Objectives 6-5
Flow Measurement System Evaluation 6-5
Sharp-Crested Weir Inspection Procedures 6-6
Parshall Flume Inspection Procedures 6-7
3 Supplementary Information 6-11
Flow Measurement Devices 6-11
Primary Devices 6-11
Secondary Devices 6-16
References 6-19
Flow Measurement Inspection Checklist 6-20
NPDES Inspection Manual 6-i June 1984
-------
Chapter Six Contents
List of Tables
6-1 Head-Discharge Relationship Formulas 6-13
for Non-Submerged Weirs
6-2 Free Flow Values of C and N for Parshall Flume 6-15
Based on the Relationship Q = CWHn
6-3 Advantages and Disadvantages of Secondary Devices 6-18
List of Figures
6-la Nomenclature of Sharp-Crested Weir 6-22
6-lb Three Common Types of Sharp-Crested Weirs 6-23
6-2 Nomograph for Discharge of 60° and 90° V-Notch Weirs 6-24
6-3 Flow Rates Curves for Cipolletti Weirs 6-25
6-4 Nomograph for Capacity of Rectangular Weirs 6-26
6-5 Parshall Flume Configuration and Nomenclature 6-27
6-6 Flow Curves for Parshall Flumes 6-28
6-7 Correction Factors for Flow Discharge Determination 6-29
for Parshall Flumes
6-8 Configuration and Nomenclature of Venturi Meter 6-30
6-9 Value of K Used To Determine Discharge with Venturi Meter 6-30
6-10 Electromagnetic Flowmeter 6-31
6-11 Propeller Flowmeter 6-31
NPDES Inspection Manual 6-ii June 1984
-------
Chapter Six
1 Evaluation of Permittee's Flow
Measurement
Objectives and Requirements
To comply with the permit requirements established under the NPDES, the
permittee must determine the quantity of wastewater being discharged.
Therefore, flow measurement is an integral part of the NPDES program and
its accuracy must be evaluated by the inspector.
The importance of obtaining accurate wastewater flow data cannot be
overemphasized. First, NPDES permits often limit the quantity (mass
loading) of a particular pollutant that may be discharged, which represents
the product of wastewater flow and pollutant concentration. Therefore, the
error involved in determining these mass loadings is the accumulation of
errors from flow measurement, sample collection, and laboratory analysis.
Second, the current compliance strategy depends heavily on the submittal of
self-monitoring data by each permittee.
In addition to providing usable information for enforcement purposes, flow
measurement serves:
• To provide operating and performance data on the wastewater
treatment plant;
• To compute treatment costs, where such costs are to be based on
wastewater volume; and
• To obtain data for long-term planning of plant capacity versus
actual capacity used.
A flow measurement inspection checklist is included in this chapter.
Evaluation of Facility Installed Devices
The accuracy of a flow measuring system (including both primary and
secondary devices) depends on many factors. Proper installation is
essential to accurate flow data. Faulty fabrication, construction, and
NPDES Inspection Manual 6-1
June 1984
-------
Chapter Six Flow Measurement
installation of primary devices are main sources of errors. Secondary
devices are also significant to a flow measurement system. Improper
calibration, misreading, and variation in the speed of totalizer drive
motors are major errors related to secondary devices.
When evaluating facility-installed devices, the inspector should:
• Verify that the system being used is accurate by measuring the flow
rate instantaneously at the primary device and comparing that
with the meter value, the chart value, or the integrator value, or
with the flow rate reported by the facility at the time the
instantaneous flow is measured by the inspector. If the values do
not agree within + 10 percent of the instantaneous value measured,
the system is not acceptable for NPDES compliance purposes.
• Collect accurate flow data during inspection, in order to validate
self-monitoring data collected by the permittee;
• Ensure that the flow measurement system or technique being used
measures the entire wastewater discharge as described by the NPDES
permit and in the manner specified by the permit (i.e., instan-
taneous or continuous). A careful inspection should be made to
determine whether recycled wastewaters or wastewater diversions are
present upstream of the system. Anomalies should be reported on
the inspection form or recorded in the bound field notebooks;
• Verify that the site chosen for flow measurement is appropriate,
and/or is in accordance with permit requirements;
• Verify that the method used for flow measurement is suitable for
type of discharge, flow range, suspended solids concentration, and
other relevant factors;
• Verify that tables, curves, and formulas are appropriate and are
correctly used to calculate flow rates; and
• Review and evaluate calibration and maintenance programs for the
discharger's flow measurement system. The permit normally requires
that calibration be checked by the permittee on a regular basis but
the minimum is a yearly calibration. Lack of such a program is
considered unacceptable for NPDES compliance purposes.
Evaluation of Permittee Data Handling and Reporting
The permittee or facility should keep flow measurement records as the
permit requires. Many flow measuring devices produce a continuous flow
chart for plant records. Flow records should contain date, flow, time of
reading, and operator's name, if applicable. Maintenance, inspection
dates, and calibration data should also be recorded.
NPDES Inspection Manual 6-2 June 1984
-------
Chapter Six
Flow Measurement
The inspector should review the permittee's records and note the presence
or absence of such data as:
• Frequency of routine operational inspections;
• Frequency of maintenance inspections;
• Frequency of flowmeter calibration; and
• Irregularity or uniformity of flow.
Evaluation of Permittee Quality Control
The purpose of quality control is to produce data that meet user require-
ments in terms of precision and accuracy. Precision refers to data
reproducibility or the ability to consistently obtain the same data from
repeated measurement of the same quality. Precision can be evaluated at
float driven devices when flows are stable. The float is pushed gently
downward, held there for 30 seconds, then allowed to return to normal on
its own. The recorded flow rate should be the same before and after the
float was moved. Accuracy can be evaluated by measuring the instantaneous
flow rate at the primary device used at the facility and comparing the
value against the value on the meter, graph, integrator, or company
record. The difference between two stable readings should not exceed + 10
percent of the measured flow at the primary device.
The accuracy of flow measurement devices varies widely with the device, its
location, the environmental conditions, and other factors such as mainte-
nance and calibration. Accuracy refers to the agreement between the amount
of a component measured by the test and the amount actually present.
Accuracy can be evaluated by installing a second flow measurement system,
sometimes referred to as a reference system. Agreement in measured flow
rates between the two systems should be within + 10 percent of the
reference rate if all conditions are as recommended for the systems.
The following quality control issues should be carefully evaluated during a
compliance inspection:
• Sound operation and maintenance of equipment;
• Accurate, current records;
• Sufficient inventory of spare parts;
• Current, valid flow measurement techniques; and
• Precise flow data.
NPDES Inspection Manual 6-3 June 1984
-------
Chapter "Six
2 Flow Measurement Compliance
Objectives
The current compliance strategy depends heavily on the permittee's
submittal of self-monitoring data. The flow measured during the NPDES
compliance inspection should verify the flow measurement data collected by
the permittee to support any enforcement action that may be necessary, and
to eventually provide a basis for reissuing or revising the NPDES permit.
Flow Measurement System Evaluation
The responsibility of the inspector during NPDES compliance flow
measurement inspection includes the collection of accurate flow data during
the inspection, as well as the validation of such data collected by the
permittee for self-monitoring purposes.
The NPDES inspector must check both the permittee's flow data and the flow
measurement system to verify the permittee's compliance with NPDES permit
requirements. When evaluating a flow measurement system, the inspector
should consider and record findings on:
• Whether the system measures the entire flow;
• The system's accuracy and good working order;
• The need for new system equipment; and
• The existence or absence of a regular calibration and maintenance
program for flow measurement equipment.
If the permittee's flow measurement system is accurate within + 10
percent, the inspector is encouraged to use the installed system. If flow
sensor or recorder is found to be inaccurate, the inspector should
NPDES Inspection Manual 6-5 June 1984
-------
Chapter Six Flow Measurement
determine whether it can be corrected in time for use during the inspec-
tion. If the equipment cannot be repaired in a timely manner, a portable
flow sensor and recorder may be used for the duration of the inspection.
If non-standard primary flow devices are being used, the permittee should
supply data on the accuracy and precision of the method being employed.
For flow measurement in pipelines, the inspector may use a portable
flowmeter. The inspector should select the flowmeter with an operating
range wide enough to cover the anticipated flow to be measured. The
selected flowraeter should be tested and calibrated prior to measurement.
The inspector should select the site for flow measurement according to
permit requirements and install the selected flowmeter per manufacturer's
specifications. The inspector should use the proper tables, charts, and
formulas as specified by the manufacturer to calculate flow rates.
Sharp-Crested Weir Inspection Procedures
The inspector has three distinct areas to investigate when evaluating the
compliance of a permittee's flow measurement system: the weir's physical
conditions, the flow measurement using staff gauge, the flow measurement
using float gauge or other appropriate sensor, and the flow measurement at
the weir plate. Staff gauges and float gauges may not be used at all
installations. (Figures 6-la and b at the end of this chapter present some
types and features of sharp-crested weirs.)
Some of the flow measurement inspection procedures pertaining to the
functional aspects of flow measurement devices are also discussed in this
section. A detailed discussion concerning the flow measurement devices is
included in a later part of this chapter.
Physical Conditions. When measuring the flow in an open channel by a
sharp-crested weir, the inspector should follow in sequence the procedures
listed below.
• Inspect weir plate, ascertaining whether
- the crest is horizontal;
the crest is at zero gauge elevation;
- the weir edge is of acceptable width and sharpness;
there is clinging debris or grease build-up;
- there is leakage between weir plate and bulkhead.
• Inspect nappe, ascertaining whether
- it Is submerged;
- it springs clear of downstream side of weir plate.
NPDES Inspection Manual 6-6 June 1984
-------
Chapter Six
Flow Measurement
Inspect approach channel, making sure there are no
- turbulent areas;
large submerged or floating objects;
excessive sediment deposits;
- excessive approach velocity due to poor design or sedimentation.
Allow flow to stabilize, to monitor an undisturbed flow condition.
Flow Measurement Using Staff Gauge. To determine head using staff gauge,
the inspector should:
• Verify that the staff gauge is set to zero head;
• Read, to the nearest division, the gauge division at which liquid
surface intersects gauge. This reading should be made at least 4 H
upstream of the weir.
• Measure head on weir from staff gauge reading; should not be less
than 0.1 feet.
To determine flow rate, use the appropriate weir table. (See Figures 6-2,
through 6-4 at the end of this chapter.)
Flow Measurement Using Float Gauge. To determine head using float gauge,
the inspector should:
• Verify that the tape is in position and that it is giving correct
reading;
• Read, to the nearest division, tape division opposite index on
float gauge. This reading should be made at least 4 H upstream of
the weir.
• Measure head on weir from float gauge reading; should not be less
than 0.1 feet.
To determine flow rate, use the appropriate head-discharge relationship
formula. (See Table 6-1 on page 6-13.)
The inspector may use an independent method of measuring head such as with
a yard stick or carpenter's rule (be sure to measure at least 4H upstream
and convert to nearest hundredth of a foot).
Parshall Flume Inspection Procedures
To evaluate compliance of a permittee's flow measurement system by Parshall
flume (see Figure 6-5 at the end of this chapter), the inspector must
investigate the system's physical conditions, the free-flow condition using
staff gauge/float gauge, and the submerged-flow condition.
NPDES Inspection Manual6^7June 1984
-------
Chapter Six Flow Measurement
Physical Conditions. When inspecting the flow measurement in an open
channel by Parshall flume, the inspector should follow in sequence the
procedures listed below.
• Observe flow upstream of flume to ascertain whether
- the flow is reasonably smooth or streamline;
the flow is distributed reasonably uniformly across channel.
• Make sure flume is located after transition point.
• Remove any objects causing disturbances of flow.
• Inspect flume for deposits of solids to ascertain build-up of
sediment in structure.
• Determine whether flow condition is free or submerged.
• Inspect stilling well to determine that
connection to channel is not clogged;
- there are no deposits;
- there are no objects interfering with float;
- inlet pipe is located at proper head measuring point.
• Clean stilling well if necessary.
Flow Measurement—Free-Flow Condition Using Staff Gauge
• To determine upstream head (Ha) using staff gauge
- verify staff gauge is set to zero head;
- verify staff gauge is at proper location (two-thirds the length
of the converging section back from the beginning of the
throat);
- read to nearest division the gauge division at which liquid
surface intersects gauge;
- read Ha in feet from staff gauge.
• To determine flow rate, use Figure 6-6 (at the end of this chapter)
in the unit desired, or use tables published in flow measurement
standard references.
Flow Measurement—Free-Flow Condition Using Float Gauge
• To determine upstream head (Ha) using float gauge
- read to nearest division the tape division opposite index on
float gauge;
- calculate Ha from float gauge reading.
NPDES Inspection Manual 6-8 June 1984
-------
Chapter Six Flow Measurement
• To determine flow rate, use Figure 6-6 in the unit desired.
Flow Measurement—Submerged-Flow Condition
In general, it is difficult to make field measurements with submerged-flow
conditions. In cases where measurements can be obtained (using a staff or
float guage), the following procedures should be followed:
• To determine upstream head using staff or float gauge
read to nearest division, and at the same time as for Hfc, the
gauge division at which liquid surface intersects gauge;
- calculate Ha from gauge reading.
• To determine downstream head (Ht>) using staff or float gauge
- read to nearest division, and at the same time as for Ha, the
gauge division at which liquid surface intersects gauge;
- calculate Hb from staff reading.
• To determine flow rate
- calculate percent submergence
- consult Figure 6-7;
- when a correction factor is obtained, use Ha and find free-flow
from Figure 6-6;
- multiply this free-flow value by the correction factor to obtain
the submerged flow.
The inspector may use an independent method of measuring head such as with
a yard stick or carpenter's rule at the proper head measurement point. Due
to the sloping water surface in the converging section of a flume, it is
essential that the proper head measurement point be used.
NPDES Inspection Manual 6-9 June 1984
-------
Chapter Six
3 Supplementary Information
Flow Measurement Devices
Flow data may be collected on an instantaneous or a continuous basis.
Instantaneous flows must be measured at the time samples are taken for
analysis in order to calculate the pollutants discharged at that particular
instant. In a continuous flow measurement system, the flows are totaled to
obtain a value for the total flow to verify NPDES permit compliance.
A typical, complete continuous flow measurement system consists of a flow
device, a flow sensor, transmitting equipment, a recorder, and a
totalizer. Instantaneous flow data, on the other hand, can be obtained
without using such a system. The primary flow device is constructed to
yield predictable hydraulic responses that are related to the rate of
wastewater or water flowing through the device. Examples of such devices
include weirs and flumes, which relate water depth (head) to flow; Venturi
meters, which relate differential pressure to flow; and electromagnetic
flow meters, which relate induced electric voltage to flow. In most cases,
a standard primary flow device has undergone detailed testing and
experimentation and its accuracy has been verified.
There are many methods of measuring flow; some are designed to measure open
channel flows, others to measure flow in pipelines. A complete discussion
of all available flow measurement methods, the theory behind them, and the
devices used are beyond the scope of this manual. Only the most commonly
used flow measurement devices and procedures on how to inspect them will be
briefly described in the following paragraphs. For details, inspectors
should consult the publications listed in the References section at the end
of this chapter.
Primary Devices
Non-submerged weirs. Weirs (Figures 6-la and b) consist of a vertical
plate with a sharp crest and are placed in a stream, channel, or partly
filled pipe. The top of the plate may be straight, V-notched, or
trapezoidal, depending on the quantity of flow passing over it. To
determine the flow rate, it is necessary only to measure the head (height)
of water above the crest of the weir. For this device to be accurate, the
crest must be kept clean, sharp, close to original dimensions, and level.
NPDES Inspection Manual 6-11 June 1984
-------
Chapter Six Flog MB
The head-discharge relationship formulas for rectangular weirs, both
contracted and suppressed, Cipolletti weirs, and V-notch weirs are given in
Table 6-1. Flow rates for 60-degree and 90-degree V-notch weirs can also
be determined from the nomograph in Figure 6-2. Flow rates for Cipolletti
weirs can also be obtained from Figure 6-3. Figure 6-4 is a nomograph for
flow rates for rectangular weirs using the Francis formulas.
When a continuous flow record is needed, secondary devices such as bubbler
meters may be used with a weir. Mechanical float and cable gauges also may
be used to measure water height.
Submerged Weirs. A submerged weir is a sharp-crested weir that is
completely under water. For all submerged weir types, Mauis's equation
(Mauis, 1949) can be used to determine the discharge:
q = 1 - ( 0.45S + 0.40 )
Ql 2(10-108)
where: Q = discharge for submerged weir in cfs
Ql = free discharge (H2 < 0) in cfs
a2\/H2
al\/Hl
where: &2 - weir area corresponding to H2
a\ = weir area corresponding to HI
Parshall Flume. The Parshall flume is comprised-of three sections: 'a
converging upstream section, a throat or contracted section, and a
diverging downstream section (Figure 6-5).
The flume operates on the principle that open channel flow, when passing a
constriction in the channel, will pass through a minimum (critical) depth.
This will produce a hydraulic head at a certain point upstream of the
constriction that is proportional to the flow. The flume size is given by
the width of the throat section.
The Parshall flume is good for measuring open channel waste flow because
the flume cleans itself; therefore, there is little difficulty with sand or
suspended solids. It is both simple and accurate.
Parshall flumes have been developed with throat width from 2.50 mm (1 inch)
to 15.24 m (50 feet). The configuration and standard nomenclature for
Parshall flumes is given in Figure 6-5. Strict adherence to all dimensions
is necessary to achieve accurate flow measurement.
WEES Inspection Manual 6-12 June 1984
-------
Table 6-1
Head-Discharge Relationship Formulas for Non-SutMergad Heirs*
Weir Type
Contracted
Suppressed
Remarks
Reference
RectanguIar
Francis formulas 0 = 3.33
0 = 3.33 L H
,3/2
Approach velocity neglected American Petroleum Institute, 1969
Clpollettl
V-Notch
Q = 3.33 KH + h)3/2-h3/2HL - 0.2 H)
Q = 3.367 L H3/2
0 = 3.367 L (H + 1.5
0 = 3.33 LKH + h?/2- rV2J Approach velocity taken
Into consideration
Approach velocity neglected Simon, 1976
Formula for Q = 2.5 H
90" V-Notch only
,2.5
NA
NA
NA
Approach velocity taken
Into consideration
V-Notch weirs are not
appreciably affected by
approach velocity
Smoot, 1974
Q = discharge In cubic feet per second L = crest length In feet
H - head In feet h = head In feet due to the approach velocity (V).
NA = Not applicable
* Selectivity of the formula depends upon the suitability and parameters under consideration.
-------
Chapter Six Flow Measurement
Flow through a Parshall flume may be either free or submerged. The degree
of submergence is indicated by the ratio of the downstream head to the
upstream head (Hb/Ha)—the submergence ratio. The flow is submerged if the
submergence ratio is:
• greater than 0.5 for flumes under 0.076 m (3 inches);
• greater than 0.6 for flumes 0.15 m to 0.23 m (6 inches to 9
inches);
• greater than 0.7 for flumes 0.3 m to 2.44 m (1 to 8 feet); or
• greater than 0.8 for flumes bigger than 2.44 m (8 feet).
For a free flow in a Parshall flume of size (W), the upstream head (Ha) and
discharge relationship is given by the general equation Q = CWHan.
Table 6-2 gives the values of C, n, and Q for different sizes (W) of the
Parshall flume. Nomographs, curves, or tables are readily available to
determine the discharge from head observations. Flow curves are shown in
Figure 6-6 to determine free flow through 0.07 m to 15.24 m (3 inches to 50
feet) Parshall flumes.
For submerged conditions, the inspector should apply a correction factor to
the free flow determined using the relationship Q = CWHn- These correction
factors are given in Figure 6-7 for different sizes of the Parshall flume.
Venturi Meter. The Venturi meter is one of the most accurate primary
devices for measuring flow rates in pipes. The Venturi meter is basically
a pipe segment consisting of an inlet section (a converging section), a
throat, and an outlet section (a diverging section) as illustrated in
Figure 6-8. A portion of potential energy transferred to kinetic energy in
the throat section causes a pressure differential which is proportional to
the flow rate. One of the advantages of the Venturi meter is that it has
low pressure loss.
Manufacturers of Venturi meters routinely size their meters for a specific
use. The accuracy of the Venturi meter is affected by changes in density,
temperature, pressure, viscosity, and pulsating flow of the fluid.
The inspector should determine whether the permittee obtains accurate flow
measurements, according to the following criteria:
• Install Venturi meter following manufacturer's instructions.
• Install Venturi meter downstream from a straight and uniform
section of pipe, at least 5 to 20 diameters, depending upon the
ratio of pipe diameter to throat diameter and whether straightening
vanes are installed upstream. Installation of straightening vanes
upstream will reduce the upstream piping requirements.
NPDES Inspection Manual 6-14 June 1984
-------
Chapter Six
Flow Measurement
Table 6-2
Free Flow Values of C and N for Parshall Flume
Based on the Relationship Q = CWHn (American Petroleum Institute, 1969)
Flume Throat, W
1
2
3
6
9
1
1.5
2
3
4
5
6
7
8
10
12
15
20
25
30
40
50
[(*) w
in
in
in
in
in
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
ft
in feet]
C
0.338
0.676
0.992
2.06
3.07
4 W(*)
ft
ft
it
11
"
"
"
"
39.38
46.75
57.81
75.25
94.69
113.13
150.00
186.88
n
1.55
1.55
1.55
1.58
1.53
1.522W0.026
11
"
'*
11
"
"
"
lf
1.6
1.6
1.6
1.6
1.6
1.6
1.6
1.6
Max. Q, cfs
0.2
0.5
1.1
3.9
8.9
16.1
24.6
33.1
50.4
67.9
85.6
103.5
121.4
139.5
200
350
600
1000
1200
1500
2000
3000
• For wastewater application, ensure that the pressure measuring taps
are not plugged.
• Calibrate Venturi meter in place by either volumetric method or
comparative salt dilution method to check the manufacturer's
calibration curve or to develop a new calibration curve.
The formula for calculating the flow in a Venturi meter is as follows:
Q = CAKN/H
where:
Q = volume of water, in cubic meters per second (cubic feet per
second)
C = discharge coefficient, approximately 0.98. C varies with
Reynold's number, meter surfaces, and installation
A = throat area, in square meters (feet) rr
"4
MPDES Inspection Manual
6-15
June 1984
-------
Chapter Six Floy Measurement
H = HI - H2, differential head, in meters (feet) of water
HI = presure head at center of pipe at inlet section, in meters (feet)
of water
H£ = pressure head at throat, in meters (feet) of water
_2j
(Obtain values of K from Figure 6-9)
/£ v
y
-
where :
g = acceleration due to gravity, 9.82 m per sec2 (32.2 feet per sec2)
d£ = throat diameter, in meters (feet)
d^ * diameter of inlet pipe, in meters (feet)
Electromagnetic Flowmeter. The electromagnetic flowmeter operates accord-
ing to Faraday's Law of Induction: the voltage induced by a conductor
moving at right angles through a magnetic field will be proportional to the
velocity of the conductor through the field. In the electromagnetic flow-
meter, the conductor is the liquid stream to be measured and the field is
produced by a set of electromagnetic coils. A typical electromagnetic
flowmeter is shown in Figure 6-10. The induced voltage is subsequently
transmitted to a converter for signal conditioning. The meter may be
provided with recorder and totalizers using electric or pneumatic transmis-
sion systems. This type of flowmeter is useful at sewage lift stations and
for measuring total raw wastewater flow or raw or recirculated sludge.
Electromagnetic flowmeters are used in full pipes and have many advantages:
accuracies of + 1 percent, a wide flow measurement range, a negligible
pressure loss, no moving parts, and rapid response time. However, they are
expensive and build-up of grease deposits or pitting by abrasive waste-
waters can cause error. Regular checking and cleaning of the electrodes
are necessary.
Propeller Meter. The propeller meter (Figure 6-11) operates on the
principle that liquid hitting the propeller will cause the propeller to
rotate at a speed proportional to the flow rate. The meter is self-
contained and requires no energy or equipment other than a mechanical
totalizer to obtain a cumulative flow reading. Equipment may be added to
the meter to produce a flow rate reading, to pace chemical feed equipment,
and to control telemetering equipment for remote readout.
Secondary Devices
Secondary devices are the devices in the flow measurement system that
translate the interaction of primary devices in contact with the fluid into
the desired records or read-out.
NPDES Inspection Manual 6-16 June 1984
-------
Chapter Six Flow Measurement
These devices can be classified into two broad classes:
• Non-recording type with direct read-out (such as a staff gauge) or
indirect read-out from fixed points, as in a chain, wire weight and
float type.
• Recording type, where the recorders may be digital or graphic.
Examples are float in well, float in flow, bubbler, electrical, and
acoustic.
The advantages and disadvantages of various secondary devices are given in
Table 6-3.
Pump Curves
It may be necessary in some wastewater facilities to measure flow by means
of the pumps through which it flows. In the case of pumps, discharge-
versus-power relationships are determined by measuring the average output
or input during the period in which discharge measurements are made.
Suitable curves may be developed from these test data. When readily
available from the manufacturer, pump curves may be used by the inspector
to measure flow.
NPDES Inspection Manual 6-17 June 1984
-------
Chapter Six
Flow Measurement
Table 6-3
Advantages and Disadvantages of Secondary Devices
Device
Advantages
Disadvantages
Hook gauge or
stage board
Differential Pressure
Measurement
a. Pressure bulb
b. Bubbler tube
Surface float
Dipper
Ultrasonic
Common, accurate
Manual only, stilling
well may be needed
No compressed air Can clog openings,
source can be directly expensive
linked to sampler
Self-cleaning, less
expensive, reliable
Inexpensive, reliable
Quite reliable, easy
to operate
No electrical or
mechanical contact
Needs compressed air
or other air source;
In-stream float catches
debris
Oil and grease will
foul probe, possible
sensor loss
Errors from heavy
turbulence and foam,
calibration procedure
is more involved than
the others
NPDES Inspection Manual
6-18
June 1984
-------
Chapter Six Flow Measurement
References
American Petroleum Institute. 1969. Manual on Disposal of Refinery
Wastes, Chapter 4.
Associated Water and Air Resource Engineers, Inc. 1973. Handbook for
Industrial Wastewater Monitoring, U.S. EPA, Technology Transfer.
Blasso, L. 1975. "Flow Measurement Under Any Conditions," Instruments and
Control Systems, 48, 2, page 45-50.
Bos, M. G. 1976. Discharge Measurement Structures. Working Group on
Small Hydraulic Structures International Institute for Land
Reclamation and Improvement, Wageningen, The Netherlands.
ISCO. Open Channel Flow Measurement Handbook. Lincoln, NB.
Mauis, F. T. 1949. "How to Calculate Flow Over Submerged Thin-Plate
Weirs." Eng. News-Record, p. 65.
Metcalf & Eddy, Inc. 1972. Wastewater Engineering, McGraw-Hill Book
Company, New York.
Robinson, A. R. 1965. Simplified Flow Corrections for Parshall Flumes
Under Submerged Conditions. Civil Engineering, ASCE.
Shelley, P. E. and G. A. Kirkpatrick. 1975. Sewer Flow Measurement; A
State of the Art Assessment. U.S. EPA, EPA-600/2-75-027.
Simon, A. 1976. Practical Hydraulics, John Wiley.& Sons, Inc., New Yo'rk.
Smoot, G. F. 1974. A Review of Velocity-Measuring Devices. USDI, U.S.
G.S. Open File Report, Reston, Virginia.
Stevens. Water Resources Data Book. Beaverton, OR.
Thorsen, T. and R. Oden. 1975. "How to Measure Industrial Wastewater
Flow," Chemical Engineering, 82, 4, page 95-100.
USDI, Bureau of Reclamation. 1967. Water Measurement Manual, 2nd Ed.
HPDES Inspection Manual 6-19 June 1984
-------
Chapter Six
Flow Measurement
A. Flog Meaaanacm. Inqpn-ti
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
No
No
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
1. Primary flow measuring device is properly installed and maintained.
2. Flow records are properly kept.
3. Sharp drops or Increases in flow values are accounted for.
4. Actual flow discharged is measured.
5. Influent flow is measured before all return lines.
6. Effluent flow is measured after all return lines.
7. Secondary instruments (totalizers, recorders, etc.) are properly operated and
8. Spare parts are stocked.
B.
Flow Measure*
1- TJ.JI ILl.t 1 JT-.
CheHrl'lAt — FluMES
1. Flow entering flume appears reasonably well distributed across the channel and
free of turbulence, boils, or other distortions.
2. Cross-sectional velocities at entrance are relatively uniform .
3. Flume is clean and free of debris or deposits.
4. All dimensions of flume are accurate.
5. Side walls of flume are vertical and smooth.
6. Sides of flume throat are vertical and parallel.
7. Flume head is being measured at proper location.
8. Measurement of flume head is zeroed to flume crest.
9. Flume is of proper size to measure range of existing flow.
10. Flume is operating under free-flow conditions over existing range of flows.
NPDES Inspection Manual
6-20
June 1984
-------
Chapter Six
Flow Measurement
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
C. Flow Measurement Inspection Checklist — tilers
1. What type of weir is being used?
2. The weir is exactly level.
3. The weir plate is plumb and its top edges are sharp and clean.
4. There is free access for air below the nappe of the weir.
5. Upstream channel of weir is straight for at least four times the depth of water
level, and free from disturbing influences.
6. The stilling basin of the weir is of sufficient size and clear of debris.
7. Head measurements are properly made by facility personnel.
8. Proper flow tables are used by facility personnel.
D. Flow Moasucenent Inspection Checklist - Other Flow Devices
1. Type of flowmeter used:
2. What are the most common problems that the operator has had with the flowmeter?
3. Measured Wastewater flow: mgd; Recorded flow: mgd; Error %
4. Design flow: mgd.
5. Flow totalizer is properly calibrated.
6. Frequency of routine Inspection by proper operator: /day.
7. Frequency of maintenance inspections by plant personnel: /year.
8. Frequency of flowmeter calibration: /month.
9. Flow measurement equipment adequate to handle expected ranges of flow rates.
10. Venturi meter is properly installed and calibrated.
11. Electromagnetic flowmeter is properly calibrated.
NPDES Inspection Manual
6-21
June 1984
-------
Chapter Six
Flow Measurement
= APPKOX. O.l"
POINT 70
MEASURE
DEPTH, H
.OH >j
SHARP - CRESTED WEIR
NAPPE
Figure 6-la. Nomenclature of Sharp-Crested Weirs
NPDES Inspection Manual
6-22
June 1984
-------
Chapter Six
Flow Measurement
£
x"
X
X
X
X
X
X
X
X
ft
.CREST
RECTANGULAR WEIR (SUPPRESSED)
^ contraction V
*- x -»«
1
RECTA N
(CONTKA
Max Level
GULAR WEIR
1TED3
j^max
t
X
1
/ / // / / s sf '/ / / s f s/s /' f s s s ss
contraction
4:1 «looa-A ^
~H\
I L -
CIPOULETTI WEIR
/ // f f' / // f " " " ''/ /
^ ®~~*-
«. /
7 H
/ t1""
— 1 r
X
*
'// / f // / S/s/r/
•^
«^- onntrantion — -^t
/,
\
/,
''/,
x ,
•*• * — H^V >^
~ X^
TRIANGULAR OR
V-NOTCH WEIR
' ' 1 / // / / ////'/////
L at least 3Hmm
X at least 2Hm
-------
Chapter Six
24
20
18
16
14
12
10
8J
"
7:
6-
5-
4-
-
3-
**
•
2-
m
-
1-
e
?
Ur
S^.
•i hi v
c "y
£ Jr
~ \
~ *
• UJ
o !r
< *
c o.
(E *
I]
§
r-7000
-6000
•5OOO
-4000
1
r3OOO
r
•2OOO
•
r 1000
•BOO
-
•600
'-
tnn
. ^^
•300 e
• O
•KX) B!^
• 80 1
" oc
-60 C
L *
o
4O o
10
30
20
10
8
6
4
3
-4OOO
I-30OO
•
-2OOO
;
'
• IOOO
-80O
;600
•
-400
rXO
-200
r 00
tn
-60 Sc
u
z
40 z
^"
30 Q-
Ul
zo x
K
UJ
10
8
6
4
3
2
L5
P- 24
':
-20
.
:I8
- (6
•W
.
-12
•
•10
•9
;8
•7
-6
5
4
3
2
1
Figure 6-2. Nomograph for Discharge (in cubic feet per second)
of 60° and 90° V-Notch Weirs (Smoot, 1974)
NPDES Inspection Manual
6-24
June 1984
-------
S!
i
00
•d
A
o
rt
§
P
g
09
I
Ln
i
c
d
I
OJ
S
rt
n
I
Ml
O
r|
1
(0
rt
rt
09
w
§
4^
-------
Chapter Six
10~? SOOO -r 46
15-
-
ZD
2.5-
30-
4.0
5.0^
"
^J
•
6Di
*
r-
5000^
20OO-1
lOOOq
,
;
/— N 5OO ~
Q J
2. :
^ 200-
CM ;
[f> inn '
H 33 I0°3
w :
fc'J \jQ
f^ ^D *V^ '
M SS "
Pn^ -
j x " z«h
O Cd '
** o£ i j "
M ^s K>j
s wo:
H W K -
ft. OH5"
^5 ^J CJ
(X -4 O
^ 1
': 3 W
* ** ^0
: oi
: w
-2 H
• ta
o
M
CQ
CJ
1^
Z
-03 M
-OB
-0.7 °-
>- 0.6 w"
a
^-0.5 ^
32
CJ
-0.4 w
?• Q
j-0.3
-0.2
- QJ
Where:
Q = discharge, in cubic
feet per second
L = length of weir, in
feet
H = head, in feet.
Figure 6-4. Monograph for Capacity of Rectangular Weirs
(American Petroleum Institute, 1969)
- •* - Tiino 1 98
NPDES Inspection Manual
-------
Chapter Six
Flow Measurement
NOTE 76cm(3,n) TO 24m 1811) FLUMES HAVE
ROUNDED APPROACH WINGWALLS
h-1-
T~
* M '!
( il il LEVEL FLCOB
1—-Jr-'—I
*TTT«;:--• ......- ... *r>^ »
~—N <=-*r'S^vtg
'I XI XI/(
ANGLE
| SUBMERGED
l| LOW
II .FBEE FLOW
|l*4**
II
SECTION L-L
LEGEND:
W Size of flume, in inches or feet.
A Length of side wall of converging section.
2/3A Distance back from end of crest to gauge point.
B Axial length of converging section.
C Width of downstream end of flume.
D Width of upstream end of flume.
E Depth of flume.
F Length of throat.
G Length of diverging section.
K Difference in elevation between lower end of flume and crest.
N Depth of depression in throat below crest.
R Radius of curved wing wall.
M Length of approach floor.
P Width between ends of curved wing walls.
X Horizontal distance to Hjj gauge point from low point in throat.
Y Vertical distance to H^ gauge point from low point in throat.
Figure 6-5. Parshall Flume Configuration and Nomenclature
NPDES Inspection Manual
6-27
June 1984
-------
Flow Measurement
GPM
1,000,000
800.OOO
600,000
SOO.OOO
400.00O
3OO.OOO
2OO.OOO
IOO,OOO
8O.OOO
60,000
50.000
40,000
30,000
20.OOO
10,000
8OOO
6OOO
5OOO
4OOO
3OOO
2OOO
GPM
IOOO
800
600
500
400
300
2OO
IOO
ao
so
so
40
3O
20
FLOW
10
a
MGO
3000
2000
- IOOO
800
600
500
400
300
20O
~~ IOO
80
60
50
40
50
20
" 10
8
6
5
r 4
, 3
2
- 10
08
0.6
0.5
04
03
0.2
- MGO
01
O.O8
0.06
0.05
004
- FLOW
O.O2
^ 1
j
|
.
/
/
/
/f
1 ' '/ /
y
/
/
/
'/,
/
7"
/
}
/
/
/
/
/
/
/
/
/t
-4-
j /
^
ft
\
A
/i
/f
-4
; ///y
1 /
; /
/
! : /
i
/
//y
/ ^
/] /
/
/
//
/
r
f/1
1 / / /
/ / i/
/f / >
i / f
V
//
'—f —
/
/ *
V
/ / /
/ /
/ ./
/ /
r A
/
/
j (>
^
I/
^— '
1
f
^
^
/
/
.
r
t
^
9-
l\ 1
f\ f
^
/
i
c
'
j
.
f
f
1
*}
/
i>
y
•-.'
'
y
f
.,
^»SS
/// .
v/
( t i
I///
> // }
7 /
'•'/
t
/ ,
'/_,
A
/ /
/ / >
l/ /A
'A
> ^
m
' / f
//
/
' i
Y
' '
Y,
JX /'/
ft f
/ / /
/ / y
( A /
T /
//
1
I
t
/
(
1
t
( / /
J '
/
V
k/
i-/
/
j /
v
Vr
//
V ,
Y
b —
/
i
1
/ .,
/ 1
'/
7
t
7
7
/i
~f~
j
1 /
'
/
(
' f
}
/
y
f
{
f
t
>
f
t
t
i ,
2 3 4 ft 6 8 IO 15 2O 3O/4O SO 8O KX>
MEAD -INCHES / /
, / ' ' ' ' / ' ' ^ J-LjJ
-
-
!
2 .3/4568 10 2/34568 10
HEAD- FEET / / J
CF5
4OOO
30OO
2000
IOOO
80O
6OO
50O
4OO
300
20O
IOO
80
60
5O
4O
30
20
IO
8
6
5
4
3
2
10
08
06
05
04
03
02
CFS
01
OO8
006
005
004
OO3
002
FLOW
0.01
rive INCHES is HKIIMUK FULL SCALE
HEAD WITH FOItOXO FLO»I AND CAM.E
MCT£»
TMIUTT su INCHES is HAJMMUM FULL
SCALE MEAD III IH FOJ«0«0 FLOAT ADO
CABLE METER
Figure 6-6. Flow Curves for Parshall Flunes (Associated
Hater and Air Resource Engineers, Inc., 1973)
NPDES Inspection Manual
6-28
June 1984
-------
Chapter Six
Flow Measurement
Submergence, — in percentage
Ha
Figure 6-7. Correction Factors for Flow Discharge Determination
for Parshall Flumes (Robinson, 1965)
June 1984
NPDES Inspection Manual
6-29
-------
Chapter Six
Flow Measurement
THROAT
INLET SECTION SECTION
HIGH
PRESSURE
TAP
OUTLET SECTION
THROAT OIA.
Figure 6-8. Configuration and Nomenclature of Venturi Meter
1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
Values of r
Figure 6-9. Value of K Used To Determine Discharge
with Venturi Meter (Associated Water and Air
Resource Engineers, Inc., 1973)
NPDES Inspection Manual
6-30
June 1984
-------
Chapter Six
Flow Measurement
INSULATING
ELECTRODE
ASSEMBLY
STEEL METER
BODY
MAGNET COILS
POTTI-NG COMPOUND
Figure 6-10. Electromagnetic Flowmeter
Reduction
gears
Stralgtenlng
vanes
Direct reading
totalizer
8»v«l geara
Prop* I tor
Figure 6-11. Propeller Flowmeter
NPDES Inspection Manual
6-31
June 1984
-------
Chapter Seven
Biomonitoring
Contents
1 Evaluation of Permittee Self-Biomonitoring Program 7-1
Objectives and Requirements 7-1
Evaluation of Permittee Biomonitoring Program 7-1
Effluent Sampling 7-2
Laboratory Audit 7-2
Test Procedures 7-6
Recordkeeping and Data Reporting 7-7
2 Compliance Biomonitoring Inspection 7-9
Objectives and Requirements 7-9
Conducting Biomonitoring 7-9
Effluent Sampling and Holding 7-10
Test Organisms 7-12
Facility and Equipment 7-12
Test Procedures 7-14
Reference Toxicants 7-15
Chain of Custody and Preservation of Documents 7-15
Data Reporting 7-16
References 7-17
List of Tables
7-1 Recommended Species and Test Temperatures 7-4
List of Figures
7-1 NPDES Bioraonitoring Evaluation Form 7-8
NPDES Inspection Manual 7-i June 1984
-------
Chapter Seven
1 Evaluation of Permittee
Self-Biomonitoring Program
Objectives and Requirements
This chapter highlights acute toxicity testing procedures which may be
required by an NPDES permit. The inspector can use this information to
guide his review of a permittee's self-biomonitoring program. Detailed
procedures for biomonitoring testing are given in the U.S. EPA Methods for
Measuring the Acute Toxicity of Effluents to Aquatic Organisms.
The objectives of a self-biomonitoring program are to
• Assess compliance with discharger's NPDES permit limitations and
requirements;
• Determine whether the records and reports required by the
discharger's NPDES permit are being maintained;
• Check the adequacy of the permittee's reports;
• Determine whether representative samples are being collected and
analyzed properly; and
• Determine whether bioassay has been conducted properly.
Evaluation of Permittee Biomonitoring Program
The evaluation of a permittee's biomonitoring program includes the
performance audit inspection (PAI) and compliance evaluation inspection
(CEI). During the PAI, the inspector must review the performance of
permittee staff and evaluate their testing and sampling procedures. A CEI
consists of an examination of the permittee's self-biomonitoring files and
records, bioassay laboratory, and sampling records.
For each set of definitive bioassay data, the 24, 48, or 96-hour LC50 or
EC50 and its 95-percent confidence limits must be calculated on the basis
of the initial volume percent of the effluent in the test solutions.
NPDES Inspection Manual 7-1 June 1984
-------
Chapter Seven Blomonltoring
The inspector should determine whether or not the permittee's biomonitoring
program meets the requirements of the permit and regulations. The
inspector should understand the permittee's biomonitoring requirements as
stated in the permit.
Effluent Sampling
When evaluating a permittee's sampling program, the inspector should verify
that:
• Sampling location, method, and frequency conform to the NPDES
permit;
• The sampling location specified in the permit is adequate to
provide a well mixed and representative sample;
• Sample devices, if used, are appropriately calibrated, clean, and
properly operated;
• Effluent samples for bioassays are properly labeled and free from
chemical preservatives.
• Samples shipped to the laboratory are refrigerated and are handled
according to approved chain-of-custody procedures; and
• Bioassay testing begins within 24 hours after sample collection.
Laboratory Audit
The inspector should observe and review the permittee's laboratory proce-
dures, equipment, facilities, and logs, or those of their contractors. The
following areas require detailed on-site observations and evaluation.
Facilities and Equipment. Effluent toxicity testing may be performed in
either a stationary or a mobile laboratory. Bioassay facilities may
include equipment for rearing, holding, and acclimating test organisms.
Water temperature should be controlled by circulating water baths or
environmental chambers during acclimation and testing. The inspector
should verify that:
• Holding, acclimation, and dilution water are temperature-controlled
and aerated with air free from oil and fumes;
• Test organisms are shielded from outside disturbances and fumes
during holding, acclimating, and bioassay;
• An alternate power generating unit is provided as a stand-by;
NPDES Inspection Manual 7-2 June 1984
-------
Chapter Seven Biononitorlng
• Thermometers, pH meters, dilutors, and other measuring devices
are calibrated by the manufacturer's recommended methods
before use and at appropriate intervals during use;
• All equipment is properly cleaned; and
• Glass, No. 316 stainless steel, and perfluorocarbons are used for
test chambers, tubing, etc.
Test Organisms. A list of recommended test organisms is included in Table
7-1. The condition, age, exposure history, and rearing or holding
conditions can all affect the results. In general, wild stock are
unacceptable unless these factors are known.
The inspector should determine whether:
• Test organisms have been exposed to pollutants or other stress,
including disease, prior to bioassay;
• Test organisms have a survival rate of 80 percent or better during
holding/acclimation;
• Holding conditions conform to EPA recommended procedures;
• For the 24-hour bioassay screening test, fathead minnows
(Pimephales promelas) or other freshwater species are used with
receiving water having a salinity of less than 5 parts per
thousand. Mysid shrimp (Mysidopsis bahia) or other saltwater
species are used with receiving water having a salinity of greater
than 5 parts per thousand; and
• The temperature at which the test organisms are maintained and what
and how they are fed.
Dilution Water. The inspector should verify that:
• Pretreatment of dilution water is limited to filtration through a
nylon sieve that has 2- to 4-millimeter mesh to remove debris or
suspended solids;
• Dilution water from receiving water, when used, is obtained from a
point close to the outfall, but one that is upstream and outside of
the influenced zone;
• Dilution water is obtained from the receiving water as close as
possible to the time the test begins, but not more than 96 hours
prior to testing;
• Dilution water is continuously pumped to acclimation tank and
dilutor; and
NPDES Inspection Manual 7-3 June 1984
-------
Chapter Seven Biomonitorlng
Table 7-1
Recommended Species and Test Temperatures
Species Test Temperature (°C)a
Freshwater
Vertebrates
Coho salmon, Oncorhynchus kisutch 12
Rainbow trout, Salmo gairdneri 12
Brook trout, Salvelinus fontinalis 12
Goldfish, Carassius auratus 20
Fathead minnow, Pimephales promelas 20
Channel catfish, Ictalurus punctatus 20
Bluegill, Lepomis macrochirus 20
Invertebrates3
Clacodera, Daphnia magna, D^. pulex^, 20
or Ceriodaphnia reticulatac 20
Amphipods, Gammarus lacustris, G_. fasciatus, 20
G_. pseudolimnaeus, or Hyalella. sp. 20
Crayfish, Orconectes sp., Cambarus sp., Procambarus sp., 20
or Pacifastacus leniusculus 12
Stoneflies, Pteronarcys sp. 12
Mayflies, Baetis sp. or Ephemerella sp. 12
Hexagenia limbata or II. bilineata 20
Midges, Chironomus sp. 20
Marine and Estuarine
Vertebrates
Sheepshead minnow, Cyprinodon variegatus 20
Mummichog, Fundulus heteroclitus 20
Longnose killifish, Fundulus similis 20
Silverside, Menidia sp. 20
Threespine stickleback, Casterosteus aculeatus 20
Pinfish, Lagodon rhomboides 20
Spot, Leiostomus xanthurus 20
Sanddab, Citharichthys stigmaeus 12
Flounder, Paralichthys dentatus, P_. lethostigma 20
English sole, Parophrys vetulus 12
Winter flounder, Pseudopleuronectes americanus 12
NPDES Inspection Manual 7-4 June 1984
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Chapter Seven Biomonitorlng
Table 7-1
Recommended Species and Test Temperatures
(continued)
Species Test Temperature (°C)a
Marine and Estuarine
Invertebrates
Shrimp, Penaeus setiferus, P^. duorarum, or P^. aztecus 20
Grass shrimp, Palaemonetes sp. 20
Shrimp, Crangon sp.20
Oceanic shrimp, Pandalus Jordani 12
Blue crab, Callinectes sapidus 20
Dungeness crab, Cancer magister 12
Mysid shrimp, Mysidopsis sp., Neomysis sp. 20
Atlantic oyster, Crassos'trea virginica 20
Pacific oyster, Crassostrea gigas 20
aTo avoid unnecessary logistical problems in trying to maintain different
test temperatures for each test organism, it would be sufficient to use a
single temperature (12°C) for cold water organisms and one temperature
(20°C) for warm organisims.
bDaphnia pulex is preferred over £. magna because it is more widely
distributed in the United States, test results are less sensitive to
feeding during tests, and it is not as easily trapped on the surface fflm.
cTest methods are under development.
(Source: U.S. Environmental Protection Agency (EPA). 1984. Methods for
Measuring the Acute Toxicity of Effluents to Aquatic Organisms, EPA
600/4-83-000. In press.)
NPDES Inspection Manual 7-5 June 1984
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Chapter Seven Biomonltoring
• When a chemically equivalent or "reconstituted" water is used, it
has a total hardness, total alkalinity, and specific conductance
within 25 percent and a pH value within 0.2 units of the receiving
water at the time of testing.
Test Procedures
The most important aspect of the biomonitoring audit is the observation of
permittee or contractor toxicity testing and related laboratory analysis.
The inspector should verify that conditions and procedures are correct in
the following areas:
• Control and effluent dilution preparation;
• Procedures for transferring, allocating, and feeding test
organisms;
• Recording of times for test set-up and initiation;
• Temperature and dissolved oxygen ranges during the test; and
• Test organism age, weight, length, and species.
Test Results. The inspector should verify that:
• The number of dead (or affected) organisms in each test container
are counted 24, 48, 72, and 96 hours after the test begins;
• The dissolved oxygen concentration and pH are measured at the
beginning of the test, and every 24 hours thereafter, in the con-
trol and in the high, medium, and low effluent concentrations for
the duration of the test;
• The specific conductance, total alkalinity, total hardness, total
ammonia nitrogen, and salinity, where applicable, are measured at
the beginning and end of the test;
• Samples are collected properly and analytical results are properly
presented;
• The 96-hour LC50 or EC50 and its 95-percent confidence limits are
calculated on the basis of the initial volume percent of the
effluent in the test solutions; and
• If other (24-, 48-, 72-hour) LC and EC values are calculated, their
95-percent confidence limits are also determined.
NPDES Inspection Manual 7-6 June 1984
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Chapter Seven Biononltoring
Recordkeeping and Data Reporting
Proper recordkeeping is essential to an effective biomonitoring program.
Bound notebooks should be used to maintain detailed records of bioassays.
Annotations should be made as soon as possible to prevent the loss of
information. When evaluating the permittee's data reporting, the inspector
should verify that the following are included:
• The name of the test method, date conducted, investigator, and
laboratory;
• Detailed information on the effluent, dilution water, test
organisms, source of the organisms, test procedure, and test
chambers;
• The definition of the adverse affect (death, immobility, etc.) used
in the test, and a summary of general observations on other effects
or symptoms;
• The number and percentage of organisms in each test chamber
(including the control chambers) that died or showed the "effect"
of the toxicity of the effluent;
• A 24-, 48-, 72-, and 96-hour LC50 or EC50 value for the test
organisms, depending on the duration of exposure. If 100-percent
effluent did not kill or affect more than 65 percent of the test
organisms, report the percentage of the test organisms killed or
affected by various concentrations of the effluent;
• The 95-percent confidence limits for the LC50 and EC50 values and
the method used to calculate them;
• The methods used for the results of all chemical analyses;
• The average and range of the acclimation temperature and the test
temperature;
• Any deviation from this method; and
• Any other relevant information.
An example of a laboratory data sheet is given in Figure 7-1.
HPDKS Inspection Manual 7-7 June 1984
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Chapter Seven
Bloaonitoring
Facility Name:
Facility Location:
Figure 7-1
HPDES BIOMONITORING EVALUATION FORM
Permit No.
Laboratory/
Investigator;
Bioassay Conditions:
Test and Type: 24-Hour Static 48-Hour Static Daily Renewal
96-Hour Flow-through 96-Hour Static
Test Starting Date:
Test Organism: Fathead Minnow
(Pimephales promelas)
Summary of Results
Mortality Observed
(Yes or No)
Stress Observed
(Yes or No)
Completion Date:
Other (Specify)
LC50
(% effluent)
Quality Assurance Summary
Control Mortality:
Temperature maintained within
+2°C of the test temperature?
Dissolved oxygen levels always
greater than 40% saturation?
Loading factor for all exposure
chambers less than or equal to
maximum allowed for the test type
and test temperature?
Water chemistry variations during
the test?
Effluent Tested;
Sampling Location:
Sample Collection Dates/Time:
Dilution Water;
Source
Acceptable Unacceptable
Yes
Yes
No
No
Yes
<20%
Type of Sample:
No
>20%
Collection Date
NPDES Inspection Manual
7-8
June 1984
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Bioaonltoring
Chapter Seven
2 Compliance Biomonitoring Inspection
Objectives and Requirements
The objectives of a compliance biomonitoring inspection are to:
• Serve as a screening mechanism isolating toxic conditions in an
effluent that may not have been detected through routine chemical
analysis;
• Evaluate compliance with water quality standards;
• Monitor toxics that may or may not be controlled through BCT/BAT;
• Evaluate permit limitations;
• Develop enforcement cases;
• Investigate probable cause violations; and
• Develop data for establishing new effluent limitations.
Conducting Biomonitoring
A biomonitoring program is conducted to evaluate an effluent based on
sampling and testing by the regulatory agency. The biomonitoring can be
conducted on-site or off-site.
On-site biomonitoring usually involves the following acute toxicity tests:
• An 8- to 24-hour range-finding (screening) bioassay;
• 24- to 96-hour static bioassays;
• A 96-hour flow-through bioassay; and
• A 24-hour QA bioassay with a reference toxicant.
NPDES Inspection Manual 7-9 June 1984
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Chapter Seven Biomonitorlng
Off-site biomonitoring usually involves:
• Collecting an effluent sample (a grab sample or a 24-hour composite
sample);
• Transporting the sample to EPA or to State laboratories; and
• Performing a preferred 24-hour static bioassay.
Effluent Sampling and Holding
The effluent sampling point must be the same as that specified in the NPDES
permit. Different locations may be used for better access to the sampling
point between the final treatment and the discharge outfall, to measure
unchlorinated effluents, or to evaluate individual waste streams.
It is important that the sample represent the "normal and typical"
discharge and operating conditions of the facility.
Flow-Through Test. If the permittee facility discharges continuously, the
effluent should be pumped directly and continuously from the discharge line
to the dilutor system for the duration of the test. If the effluent cannot
be pumped directly and continuously to the dilutor system, the following
alternative methods may be employed for collection of the effluent:
• Where the calculated retention time of the effluent is less than 14
days, one to four grab samples are collected daily approximately 6
hours apart, or a composite sample is taken. Grab samples should
not be combined. The previously collected sample is discarded and
the container is refilled with the fresh effluent. If the chemical
composition or concentration of the effluent does not vary, a
single daily grab sample is sufficient.
• Where the calculated retention time is 14 days or longer, a single
grab sample or composite sample is collected daily. Here again,
the volume of sample remaining from the previous day is discarded
and replaced by the fresh sample (static renewal).
If the permittee's discharge is intermittent, one of the following
procedures may be appropriate:
• Where a continuous discharge occurs during one or two 8-hour work
shifts, collect one grab sample of sufficient volume to supply the
dilutor for 24 hours midway during the discharge period, or collect
a composite sample.
• Where a facility treats and releases wastewater in a batch
discharge, collect a single grab sample.
• Where the facility discharges wastewater to an estuary only during
on outgoing tide, collect a single grab sample or composite
sample. An alternate sampling method would be to pump effluent
from the final waste lagoon adjacent to the discharge pipe
continuously.
NPDES Inspection Manual 7-10 June 1984
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Chapter Seven Biononitorlng
Static Test. The following effluent sampling methods are recommended for
static tests. If the facility discharge is continuous, one of the
following approaches is used:
• If the calculated retention time is less than 14 days, collect four
grab samples daily and test each separately to determine the
variability in toxicity, or collect 24-hour composite samples daily
and test them in a static or static renewal test.
• If the calculated retention time is less than 14 days, but the
wastewater does not vary in chemical composition or concentration,
collect a single grab or composite sample for a static non-renewal
test.
• If the calculated retention time of a continuously discharged
wastewater is 14 days or greater, only one static test, using a
single grab or composite sample, is needed.
If the facility discharge is intermittent, one of the following approaches
is used:
• Where the effluent is continuously discharged during one or two
8-hour work shifts, collect one grab sample midway through the
shifts.
• Where the facility treats and releases the wastewater as a batch
discharge, collect a single grab sample for the test.
• Where the facility discharges wastewater to an estuary only during
an outgoing tide, collect a single grab sample.
• At the end of the shift, clean up activities may result in
discharge of a slug of toxic waste. If so, a separate toxicity
test may be advisable.
Effluent variability may be estimated from a review of self-monitoring or
by continuous monitoring of parameters such as pH or conductivity. From
these data one may calculate a mean and variance. If the relative
variability /variance^ exceeds .5, the wastewater is highly variable.
I mean
Effluent grab samples must be stored in covered, unsealed containers.
Although it is desirable to refrigerate samples before the test, it is
often convenient to store samples in a constant-temperature water bath or
controlled-environment room at the temperature at which the test is
conducted. The test should be initiated as soon as possible, but no longer
than 24 hours after collection of the effluent.
The persistence of an effluent's toxicity may be a factor in determining
specific toxicity limits in an NPDES permit, and is determined by measuring
its toxicity upon collection and again after holding 96 hours. If after
holding the effluent 96 hours its toxicity has not decreased by 50 percent
NPDES Inspection Manual 7-11 June 1984
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Chapter Seven Biononitorlng
or more, it is classified as persistent. (When special tests such as
persistence are conducted, the exact methodology must be detailed in the
report.)
Test Organisms
Certain test organism criteria that the inspector should check in the
laboratory include the following:
• Age of test organisms: Juvenile fish (15-60 days) are preferred
for acute toxicity testing.
• Feed test organisms daily and clean holding tanks at least twice a
week.
• A daily log of feeding, mortality, and observations should be kept.
• Follow the following procedures for holding test organisms:
- Quarantine new test organisms for at least 10 days
- Acclimation should be gradual. Maximum changes permitted are 3°C
in water temperature or 3 0/00 in salinity in a 12-hour period,
or total change of 6°C or 6 0/00 salinity
- Maintain dissolved oxygen levels above 40-percent saturation
(warm water species) and above 60-percent saturation (cold water
species).
• Record source of the test organisms (hatchery, in-house, or other
source).
• Test organisms should be handled as little as possible to minimize
stress.
- Dipnets should be used for large organisms;
- Pipettes should be used for transferring small organisms such
as daphnids and midge larvae.
Facility and Equipment
General Requirements. Effluent toxicity tests may be carried out in a
fixed or mobile lab. Depending on the scope of the bioassay program,
facilities may include equipment for rearing, holding, and acclimating
organisms. Temperature control is achieved using circulating water baths
or environmental chambers. Appropriate dilution water may be groundwater,
surface water, reconstituted water, or dechlorinated tap water. Holding,
acclimation, and dilution water should be temperature-controlled and
aerated whenever possible. Air used for aeration must be free of oil and
NPDES Inspection Manual 7-12 June 1984
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Chapter Seven Bioaonitorlng
fumes; filters to remove oil in water are desirable. Test facilities must
be well ventilated and free of fumes. During holding, acclimating, and
testing, test organisms should be shielded from disturbances.
Some organisms may have special environmental requirements such as flowing
water, fluctuating water levels, or substrate that must be provided.
During holding, acclimating, and testing, immature stream insects should
always be in flowing water, as described by Nebeker and Lemke (1968);
penaeid shrimp and bottom-dwelling fish should be provided a silica and
substrate. Since cannibalism can occur among many species of arthropods,
they should be isolated by some means (e.g., with screened compartments),
or the claws of crabs and crayfish should be bound.
Construction Materials. Glass, No. 316 stainless steel, and perfluoro-
carbon plastics (Teflon r ) should be used in the construction of the test
equipment whenever possible. Linear polyethylene may also be used with
some types of effluents but should be avoided with those containing
synthetic organic compounds or pesticides. Unplasticized plastics such as
polyethylene, polypropylene, TYGON r and fiberglass can be used for
holding, acclimating, and dilution-water storage tanks, and in the water
delivery system. Copper, galvanized material, rubber, brass, and lead must
not come in contact with holding, acclimation, or dilution water, or with
effluent samples and test solutions.
Effluent Delivery System (Flow-Through Test Only). The flow-through
proportional-dilutor delivery system has proven to be the best and the
preferred system for routine effluent toxicity tests conducted in both
fixed and mobile laboratories. Dilutors with solenoid valve system are
preferred, but the vacuum siphon system is acceptable, if funds are
limited.
The flow rate through the proportional dilutor must provide for at least
five complete water volume changes in 24 hours in each test chamber, plus
sufficient flow to maintain an adequate concentration of dissolved oxygen.
The flow rates through the test chambers should not vary by more than 10
percent among test chambers at any time during any test. The dilutor
should also be capable of maintaining the test concentration in each test
chamber within 5 percent of the starting concentration for the duration of
the test. The dilutor should be checked and calibrated before and after
each test.
Test Chambers. Test chambers used in flow-through tests are usually
constructed of 1/4 inch plate glass held together with clear silicone
adhesive. All joints should be smooth. Stainless steel (No. 304 or No.
316) can be used in the construction of test chambers, but must be of
welded, not soldered, construction. Plastic chambers can be used but
should be discarded after test completion.
The test chambers most commonly used in static tests are wide-mouth, 3.8
liter (1-gallon) or 19.0-liter (5-gallon) soft-glass bottles or aquaria.
Containers such as 10- to 20-cm diameter culture dishes or beakers may be
more suitable as test chambers for fish eggs and/or larvae and small
NPDES Inspection Manual 7-13 June 1984
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Chapter Seven Blomonltoring
crustacea. Special glass or stainless steel test chambers can be
constructed to accommodate test organisms requiring special physical
conditions. These chambers should be covered and provide 5 cm of test
solution.
All test chambers, whether new or used, must be washed as described in
Methods for Measuring the Acute Toxicity of Effluents to Aquatic Organisms.
Dilution Water. Receiving water is the preferred source. It should be
obtained upstream of or outside of the influence of the effluent. In an
estuarine environment, the dilution water should have the same salinity as
that at the receiving site.
Pretreatment of the dilution water should be limited to filtration through
a nylon sieve having 2-millimeter or larger openings to remove debris
and/or break up large floating or suspended solids. Dilution water should
be collected no earlier than 48 hours before testing.
If the receiving water is unsuitable as dilution water, use "reconstituted"
water. This water must have a total hardness, total alkalinity, specific
conductance within 25 percent, and pH within 0.2 units of the receiving
water. Recommended procedures for preparing "reconstituted" water are
given in Methods for Measuring the Acute Toxicity of Effluents to Aquatic
Organisms. Salt water media such as INSTANT OCEAN r and RILA SALTS r are
available commercially.
Test Procedures
Range-Finding (Screening) Test. It may be necessary to conduct an
abbreviated, preliminary, range-finding or screening test to determine the
concentrations that should be used in the definitive tests. The screening
can be either a static or flow-through test. Static tests use five
organisms in three to five effluent dilutions, and a control for 8 to 24
hours. If the range-finding test is to be conducted with the same sample
of the effluent as the definition test, the duration of the range-finding
test cannot exceed 24 hours.
Definitive Test. The determination of an LC50 or EC50 must employ a
control and at least five concentrations of effluent in an exponential
series.
If 100-percent effluent does not kill (or affect) more than 65 percent of
the organisms exposed to it, the percentage of organisms killed (or
affected) by various levels of the effluent in the receiving water must be
reported. A test is not acceptable if more than 10 percent of the
organisms die in the control.
Number of Test Organisms. At least 20 organisms of a given species must be
exposed to each treatment in two or more replicates. To qualify as true
replicates, no water connections can exist between replicate test
chambers.
NPDES Inspection Manual 7-14 June 1984
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Chapter Seven __ ___ Blomonltoring
Loading of Test Organisms. For flow-through tests, loading in the test
chambers must not exceed 5 grams per liter at temperatures of 20°C or less,
or 2.5 grams per liter at temperatures above 20°C.
For static tests, loading in the test chambers must not exceed 0.8 grams
per liter at temperatures of 20°C or less and 0.4 grams per liter at
temperatures above 20°C.
Water Temperature. Maintain the water temperature within +2.0°C of the
recommended temperature (Table 7-1).
Dissolved Oxygen. Avoid aeration that may alter the results of toxicity
tests. However, the dissolved oxygen concentration (DO) in the test
solution should not exceed 40-percent saturation for warm water species and
60-percent saturation for cold water species. The turnover rate of the
solutions in the test chambers may be increased to maintain acceptable DO
levels. If the increased turnover rate does not maintain adequate DO
levels, dilution water must be aerated.
Beginning the Test. The test begins when the test organisms are first
exposed to the effluent.
- Flow-through test—The dilutor system should be in operation 24
hours before test organisms are added and the test begins. During
this period effluent volumes, temperature, and flow rates are
adjusted.
Static test—The effluent is added to the dilution water and mixed
well by stirring with a glass rod. The test organisms are placed
in the chambers within 30 minutes.
Feeding. Organisms should not be fed during the acute toxicity test unless
they are newly hatched or very young. In the case of fish, feeding should
be terminated 48 hours before the beginning of the test. Follow the
recommendations for other standard toxicity tests.
Duration. The test duration may range from a minimum of 8 hours to 96
hours, depending on the test organism used, the purpose of the test, and
whether it is a range-finding test or a definitive test.
Reference Toxicants
Reference toxicants are used to establish the sensitivity of the test
organisms. A laboratory performs a definitive 24- or 48-hour static
bioassay with the reference toxicant to establish a median response. A
variety of compounds are available from U.S. EPA EMSL-Cincinnati. The LC50
of a batch of test organisms can be evaluated. For example, if the LC50 of
a reference toxicant does not fall in the recommended range for the test
organisms, the sensitivity of the organisms and/or the quality of the
bioassays are suspect.
NPDES Inspection Manual 7-15 June 1984
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Chapter Seven Blomonltoring
Chain of Custody and Preservation of Documents
Results obtained by persons having expertise in conducting sampling and
biomonitoring are valid. Normal EPA chain-of-custody procedures should be
used. However, an additional effort in custodial care is absolutely
required to ensure the admission of biomonitoring information in
enforcement proceedings.
For on-site biomonitoring, chain-of-custody records are those that show the
source of the materials tested and that indicate that test results are not
rendered inaccurate by deliberate tampering or unintentional error.
For biomonitoring off-site, chain of custody consists of records and/or
labels, a field data sheet, and/or a field logbook showing where, when, and
by whom a sample was taken and the persons to whom custody was relinquished
throughout the sampling and testing process, together with appropriate
notations in the laboratory logbook listing the names of sample custodians,
as well as notations on the security measures taken to protect the
integrity of the sample during testing.
Data Reporting
The primary purpose of a compliance biomonitoring inspection is to
establish compliance status with biomonitoring requirements in an NPDES
permit and/or to evaluate the effluent's potential for toxicity to aquatic
life in the receiving waters. This is accomplished by a thorough
evaluation of compliance biomonitoring data and is determined through a
comparison of the following parameters:
• Toxicity of the waste (LC50 or EC50) expressed as a percent
dilution;
• Instream waste concentration (IWC) of the effluent;
• Potential for chronic and acute toxicity of waste in the receiving
water, including persistence, carcinogenicity, mutagenicity, and
teratogenicity;
• Permit limits, if contained in the permit; and
• Chemical parameters of effluent measured in conjunction with the
bioassay, such as dissolved oxygen, temperature, pH, conductivity,
metals, and organics.
Three types of effluent biomonitoring results must be recorded:
• Biological data including length, weight, and/or age of test
organisms and number of test organisms affected;
NPDES Inspection Manual 7-16 June 1984
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Chapter Seven Bioaonitorlng
• Physical and chemical data, including dissolved oxygen,
temperature, pH, specific conductivity, total alkalinity, hardness,
salinity, total ammonia nitrogen; and
• LC50, EC50, and their 95-percent confidence limits.
A report of the results of a biomonitoring test must include the elements
listed under Recordkeeping and Data Recording on page 7-7.
References
Davey, E.W., et al. 1970. "Retrieval of trace metals from marine culture
media." Limnol. Oceanogr. 15:486-488
Kester, D. R., et al. 1967. "Preparation of artificial seawater."
Limnol. Oceanog. 12:176-179
Marking, L.L. and V.K. Dawson. 1973. "Toxicity of quinaldine sulfate to
fish." Invest. Fish Contr. No. 48, U.S. F&WS, Washington, D.C. 8pp
Nebeker, A.V. and A.E. Lemke. 1968. "Preliminary studies on the tolerance
of aquatic insects to heated waters." J. Kans. Entomol. Soc. 41:413-418
U.S. Environmental Protection Agency (EPA). 1984. Methods for Measuring
the Acute Toxicity of Effluents to Aquatic Organisms, EPA 600/4-83-000. In
press.
Zaroogian, G.E., G. Pesch and G. Morrison. 1969. "Formulation of an
artificial seawater media suitable for oyster larvae development."
Amer. Zool. 9:141
Zillioux, E. J., et. al. 1973. "Using Artemia to assay oil dispersant
toxicities." J. Water Poll. Fed. 45:2389-2396
NFDES Inspection Manual 7-17 June 1984
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Chapter Eight
Laboratory Quality Assurance
Contents Page
Objectives and Requirements 8-1
Evaluation of Permittee Laboratory Analytical Procedures 8-2
Evaluation of Permittee Laboratory Facilities and Equipment 8-2
Laboratory Services 8-3
Instruments and Equipment 8-3
Supplies 8-4
Evaluation of the Precision and Accuracy of the Permittee
Laboratory 8-4
Evaluation of Permittee Data Handling and Reporting 8-6
Evaluation of Permittee Sample Handling Procedures 8-7
Evaluation of Permittee Laboratory Personnel 8-7
References 8-8
Laboratory Quality Assurance Checklist 8-9
NPDES Inspection Manual 8-i June 1984
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Chapter Eight
Laboratory Quality Assurance
Objectives and Requirements
The analytical laboratory provides both qualitative and quantitative
information for use in determining the extent of the permittee's compli-
ance. To be valuable, the data must accurately describe the characteris-
tics and concentrations of constituents in the samples submitted to the
laboratory. The objectives of laboratory quality assurance are to monitor
the accuracy and precision of the results reported and to meet reliability
requirements.
Quality assurance (QA) refers to a total program for ensuring the reliabil-
ity of data and includes administrative procedures and policies regarding
personnel, resources, and facilities. Quality assurance is required for
all functions bearing on environmentally related measurements. This
includes activities such as: project/study definition; sample collection;
laboratory analysis; data validation, analysis, reduction, and reporting;
documentation; and data storage systems. Thus the QA program is designed
to evaluate and maintain the desired quality of data. Quality control
(QC), a function of QA, is the routine application of procedures for
controlling the accuracy and precision of the measurement process such as
the proper calibration of instruments or the use of appropriate analytical
grade reagents.
Laboratory quality assurance is required by 40 CFR Section 122.4l(e), which
states that adequate laboratory and process controls, including appropriate
quality assurance procedures, must be provided. Each permittee's labora-
tory should have a quality assurance program. The QA program should be
documented in a written quality assurance manual that is distributed to all
personnel responsible for analyses. This manual should clearly identify
the individuals involved in the quality assurance program and their
responsibilities, and should document the laboratory's standard operating
procedures that meet user requirements in terms of specificity, complete-
ness, precision, accuracy, representativeness, and comparability.
NPDES Inspection Manual 8^1 June 1984
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Chapter Eight Laboratory Quality Assurance
The information in this chapter is comprehensive and may not be applicable
to every laboratory. The size of the laboratory should be considered in
determining the appropriateness of this information.
A Laboratory Quality Assurance Checklist for the inspector's use is
included at the end of this chapter. For detailed information concerning
laboratory quality assurance, see the EPA Handbook for Analytical Quality
Control in Water and Wastewater Laboratories.
Evaluation of Permittee Laboratory Analytical Procedures
It is important that the methods used by permittee laboratories are
uniform, thus eliminating the methodology as a variable when data are
compared or shared among laboratories. Procedures used by the permittee's
laboratory should be selected by consulting 40 CFR 136 or EPA for approval
of alternative methods. Alternative test procedures may be implemented
only if the required written EPA approval has been obtained, as specified
by 40 CFR 136.4 and 136.5, and promulgated under P.L. 92-500.
Standardized test procedures that have been promulgated under 40 CFR 136
are covered in Methods for Chemical Analysis of Water and Wastes (EPA,
1979). Revisions and new additions to this publication are made whenever
new analytical techniques or instruments are developed. These are accepted
after publication in the Federal Register. Other acceptable sources are
the latest approved editions of Standard Methods for the Examination of
Water and Wastewater, the ASTM Annual Book of Standards, Part 31, Water,
and the USGS Methods for Collection and Analysis of Water Samples for
Dissolved Minerals and Gases.
In evaluating laboratory analytical procedures, the inspector should verify
the following:
• A QC record is maintained on media preparation, instrument
calibration and maintenance, and purchase of supplies;
• QC checks are made on materials, supplies, equipment, instruments,
facilities, and analyses;
• Steps and procedures are followed as stated in the method; and
• Documentation is available that explains the rationale and
applicable conditions for any deviations from test procedures.
Evaluation of Permittee Laboratory Facilities and Equipment
The maintenance of the laboratory's facilities and equipment is an
important factor in laboratory quality assurance.
NPDES Inspection Manual 5-2June 1984
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Chapter Eight Laboratory Quality Assurance
Laboratory Services
The quality of laboratory services available to the analyst will affect the
reliability of the data. The inspector should verify that the following
items are provided:
• An adequate supply of distilled water, free from interferences and
other undesirable contaminants. Routine water quality checks
should be conducted and documented;
• Adequate bench, instrumentation, storage and records-keeping
space;
• Adequate lighting and ventilation;
• Dry, uncontaminated compressed air when required;
• Efficient fume hood systems;
• Hot plate, refrigerator for samples, pH meter, thermometer,
balance;
• Electrical power for routine laboratory use and, if appropriate,
voltage-regulated sources for delicate electronic instruments; and
• Emergency equipment, fire extinguisher, eye wash station, shower,
first aid kit, gloves, goggles.
Instruments and Equipment
The analytical laboratory depends heavily on instrumentation. To a certain
extent, analytical instrumentation is always in the development stage;
manufacturers are continually redesigning and upgrading their products,
striving for miniaturization, enhanced durability and sensitivity, and
improved automation.
In evaluating laboratory instruments and equipment, the inspector should
verify that:
• Standard and specific procedures for cleaning glassware and
containers are followed;
• Written requirements for daily operation of instruments and
equipment are provided and followed;
• Standards are available to perform standard calibration procedures;
• Written trouble-shooting procedures are available; and
NPDES Inspection Manual 5^3 June 1984
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Chapter Eight Laboratory Quality Assurance
• Written schedules for required or recommended replacement,
cleaning, checking, and/or adjustment by service personnel are both
available and followed.
Supplies
Chemical reagents, solvents, and gases are available in a wide variety of
grades of purity, ranging from technical grade to various ultrapure
grades. The purity of the materials required in analytical chemistry
varies with the type of analyses. The parameter being measured and the
sensitivity and specificity of the detection system are important factors
in determining the purity of the reagents required. Reagents of lesser
purity than that specified by the method should not be used.
In evaluating laboratory supplies, the inspector should verify that:
• The required reagent purity for the specific analytical method is
met;
• Standard reagents and solvents are stored according to the
manufacturer's directions;
• Working standards are checked frequently to determine changes in
concentration or composition;
• Concentrations of stock solutions are verified before being used to
prepare new working standards;
• Laboratory supplies with limited shelf life are dated upon receipt
and shelf life recommendations, including the discard date on the
container and the storage requirements, are observed;
• Reagents are prepared and standardized against reliable primary
standards; and
• Standards and reagents are properly labeled.
Evaluation of the Precision and Accuracy of the Permittee Laboratory
The purpose of laboratory control procedures is to ensure high-quality
sampling and analyses by the use of control samples, control charts,
reference materials, and instrument calibrations. It is essential that
controls are initiated and maintained throughout the analysis of samples.
Specifically, each testing batch must contain at least one blank,
duplicate, and spiked (as applicable) sample analysis. It is equally
important that the type of control sample selected—blank, duplicate,
spike, etc.—provide the desired information.
NPDES Inspection Manual 8-4 June 1984
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Chapter Eight Laboratory Quality Assurance
The precision of laboratory findings refers to the reproducibility of
replicate observations. In a laboratory quality assurance program,
precision is determined by the use of actual water samples that cover a
range of concentrations and a variety of interfering materials usually
encountered by the analyst. Accuracy refers to the degree of difference
between observed values, and known or actual values. The accuracy of a
method may be determined by replicate analyses of samples to which known
amounts of reference standards have been added (spiked samples).
To determine whether a permittee's laboratory has established the precision
and accuracy of its analytical procedures, the inspector should verify
that:
• A minimum of seven replicates are analyzed for each type of quality
control check (duplicate samples, split samples, spiked samples,
and sample preservative blanks), and that this information is on
record.
• Precision and accuracy data are plotted by means of quality control
charts to determine whether valid, questionnable, or invalid data
are being generated from day to day.
In evaluating the precision of the measurement process, the inspector
should verify that:
• Control samples are introduced into the train of actual samples to
monitor the performance of the analytical system;
• Duplicate analyses are performed with each batch of samples to
determine precision;
• Precision control charts for each analytical procedure are prepared
and used;
- Precision limits are established based on standard deviations
with upper and lower control limits being established at three
times the standard deviation above and below the central line;
- The upper and lower warning limits are established at twice the
standard deviation above and below the central line;
• Corrective actions are taken when data fall outside the warning and
control limits; and
• The out-of-control data and the corrective action taken are fully
documented.
In evaluating accuracy, the inspector should verify that:
• Control samples are introduced into the train of actual samples to
monitor the performance of the analytical system;
NPDES Inspection Manual JF3 June 1984
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Chapter Eight Laboratory Quality Assurance
• Spiked samples are used to monitor accuracy;
• Accuracy control charts for each analytical procedure are prepared
and used;
- Accuracy limits are established based on standard deviations
with upper and lower control limits being established at three
times the standard deviation above and below the central line;
The upper and lower warning limits are established at twice the
standard deviation above and below the central line. (Note:
Some parameters have a defined warning limit required by 40 CFR
136.)
• Corrective actions are taken when data fall outside the warning and
control limits; and
• The out-of-control data or situation and the corrective action
taken are fully documented.
Evaluation of Permittee Data Handling and Reporting
An analytical laboratory must have a system for uniformly recording,
processing, and reporting data. In evaluating permittee data handling and
reporting, the inspector should verify that:
• Correct calculation formulas are used to reduce numbers to their
simplest factors for quick, accurate calculation;
• Round-off rules are uniformly applied;
• Significant figures are established for each analysis;
• Provisions are available for cross-checking calculations;
• Control chart approaches and statistical calculations have been
determined for the purposes of quality assurance and reporting;
• The report forms provide complete data documentation and permanent
recording, and facilitate data processing;
• The program for data handling provides data in the form/units
required for reporting;
/
• Laboratory records are kept readily available to the regulatory
agency for a minimum of three years; and
• Laboratory notebooks or preprinted data forms are permanently bound
to provide good documentation.
NPDES Inspection Manual 8-6 June
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Chapter Eight Laboratory Quality Assurance
Evaluation of Permittee Sample Handling Procedures
Proper sample handling procedures are necessary in the laboratory from the
time the sample is received until it is discarded. In evaluating labora-
tory sample handling procedures the inspector should verify that:
• The laboratory has a sample custodian;
• The laboratory area is a secured area and is restricted to
authorized personnel only;
• The laboratory has a sample security area that is dry, clean, and
isolated, has sufficient refrigerated space, and can be securely
locked from the outside;
• Samples are handled by a minimum number of people;
• All incoming samples are received by the custodian, who signs the
chain-of-custody record sheet accompanying the samples and retains
the sheet as a permanent record;
• The custodian has ensured that samples are properly stored;
• Only the custodian distributes samples to personnel who are to
perform analyses;
• The analyst keeps a laboratory notebook or analytical worksheet
identifying and describing the sample, the procedures performed,
and the results of the testing. The notes are dated, indicate who
performed the tests, and include any abnormalities that occurred
during the testing procedure. The notes are retained as a
permanent record in the laboratory; and
• There are accurate and up-to-date care and custody records for
handling samples.
Evaluation of Permittee Laboratory Personnel
Analytical operations in the laboratory vary in complexity. Consequently,
work assignments in the laboratory should be clearly defined. All ana-
lysts, both professional and subprofessional, should be thoroughly instruc-
ted in basic laboratory operations. Those performing complex analytical
tasks should be qualified and trained to do so. All of the analysts must
follow specified laboratory procedures, and be skilled in using the
laboratory equipment and techniques required in the analyses for which they
are responsible.
NPDES Inspection Manual 5^7 June 1984
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Chapter Eight Laboratory Quality Assurance
In evaluating laboratory personnel, the inspector should consider the
following factors:
• Adequacy of training;
• Skill and diligence in following procedures;
• Skill in using equipment and analytical methods; and
• Precision and accuracy in performing analytical tasks.
References
ASTM. 1975. Annual Book of Standards, Part 31, Water. American Society
for Testing and Materials (ASTM), Philadelphia, PA.
AWWA, APHA, and WCPF. Standard Methods for the Examination of Water and
Wastewater. Use the most current, EPA-approved edition.
Brown, E., Skougstad, M.W., Fishman, M. J. 1970. Methods for Collection
and Analysis of Water Samples for Dissolved Minerals and Gases. U.S.
Geological Survey Techniques of Water Resources Inv., Book 5.
Delfino, J. J. 1977. "Quality Assurance in Water and Wastewater Analysis
Laboratories." Water and Sewage Works, 124(7): 79-84.
EPA. 1979a. Handbook for Analytical Quality Control in Water and
Wastewater Laboratories. EPA-600/4-79-019.
EPA. 1979b. Methods for Chemical Analysis of Water and Wastes.
EPA-600/4-79-020.
Plumb, R. H., Jr. 1981. "Procedure for Handling and Chemical Analysis of
Sediment and Water Samples." Technical Report EPA/CE-81-1.
NPDES Inspection Manual SFS" June 198T
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Laboratory Quality A
A. General
Yes
No
N/A
1.
Written
laboratory
quality
assurance
manual
is
available.
B • Laboratory Procedbres
Yes
Yes
Yes
Yes
Yes
ND N/A
No N/A
No N/A
No N/A
No N/A
Yes
No N/A
1.
2.
3.
4.
5.
6.
7.
8.
EPA approved analytical testing procedures are used.
If alternate analytical procedures are used, proper approval has been obtained.
Calibration and maintenance of
Quality control procedures are
Quality control procedures are
Duplicate samples are analyzed
Spiked samples are used %
Commercial laboratory is used
instruments and equipment is satisfactory.
used.
adequate.
% of tine.
of time.
Name
Address
Contact
Phone
C. laboratory EariUHeB and Equfpneot
Yes No N/A
Yes No N/A
Yes ND N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1. Proper grade distilled water is available for specific analysis.
2. Dry, uncontaminated compressed air is available.
3. Fume hood has enough ventilation capacity.
4. The laboratory has sufficient lighting.
5. Adequate electrical sources are available.
6. Instruments/equipment are in good condition.
7. Written requirements for daily operation of instruments are available.
-------
Laboratory Quality AE
Checklist (continued)
C. Laboratory
and
(continued)
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
8. Standards are available to perform daily check procedure.
9. Written trouble-shooting procedures for instruments are available.
10. Schedule for required maintenance exists.
11. Proper volumetric glassware is used.
12. Glassware is properly cleaned.
13. Standard reagents and solvents are properly stored.
14. Working standards are frequently checked.
15. Standards are discarded after recommended shelf life has expired.
16. Background reagents and solvents run with every series of samples.
17. Written procedures exist for cleanup, hazard response methods, and applications
of correction methods for reagents and solvents.
18. Gas cylinders are replaced at 100-200 psi.
D. Laboratory's Precisian, Accuracy, and Control Procedures
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1. A minimum of seven replicates is analyzed for each type of control check
and this information is on record.
2. Plotted precision and accuracy control charts are used to determine whether
valid, questionable, or invalid data are being generated from day to day.
3. Control samples are introduced into the train of actual samples to ensure that
valid data are being generated.
4. The precision and accuracy of the analyses are good.
8-10
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Laboratory Quality Assurance Checklist (Continued)
E. Data
Reporting
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
Yes No N/A
1. Round-off rules are uniformly applied.
2. Significant figures are estabished for each analysis
3. Provision for cross-checking calculation is used
4. Correct formulas are used to reduce to simplest factors for quick,
calculation
correct
5. Control chart approach and statistical calculations for quality assurance and
report are available and followed
6. Report forms have been developed to provide complete data documentation and
permanent records' and to facilitate data processing
7. Data are reported in proper form and units
8. Laboratory records are kept readily available to regulatory agency
period of time
9. Laboratory notebook or preprinted data forms are permanently bound
good documentation
10. Efficient filing system exists enabling prompt channeling of report
for required
to provide
copies
F. Laboratory Personnel
Yes No N/A
1. The analyst has appropriate training
Yes No N/A
2. The analyst follows the specified procedures
Yes No N/A
3. The analyst is skilled in performing analyses
8-11
. GOVERNMENT PRINTING OFFICEl 1984-421-545/11828
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