Handbook of Water and Wastewater Treatment Plant Operations - Chapter 1 ppsx

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A CRC Press Company
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Water and Wastewater
Treatment Plant
Operations
Handbook of
Frank R. Spellman
© 2003 by CRC Press LLC

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Printed in the United States of America 1 2 3 4 5 6 7 8 9 0
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Library of Congress Cataloging-in-Publication Data

Spellman, Frank R.
Handbook of water & wastewater treatment plant operations / by Frank R. Spellman.
p. cm.
Includes bibliographical references and index.
ISBN 1-56670-627-0 (alk. paper)
1. Water—treatment plants—Handbooks, manuals, etc. 2. Sewage disposal
plants—Handbooks, manuals, etc. 3. Water—PuriÞcation—Handbooks, manuals, etc. 4.
Sewage—PuriÞcation—Handbooks, manuals, etc. I. Title: Handbook of water and
wastewater treatment plant operations. II. Title.
TD434.S64 2003
628.1

¢

62—dc21 2003040119
© 2003 by CRC Press LLC

Preface

Water does not divide; it connects. With simplicity it links
all aspects of our existence.

David Rothenberg and Marta Ulvaenus

In

Handbook of Water and Wastewater Treatment Plant
Operations

, the intent of the author is twofold. The Þrst
intent is to consolidate the information and experience in
waterworks and wastewater treatment plant operations
that have evolved as a result of technological advances in
the Þeld, and as a result of the concepts and policies
promulgated by the environmental laws and the subse-
quent guidelines. The second intent is to discuss step-by-
step procedures for the correct and efÞcient operation of
water and wastewater treatment systems. Tertiary to this
twofold intent is the proper preparation of operators to
qualify for state licensure and certiÞcation examinations.
With the impetus given to water quality improvement
through the Municipal Construction Grants Program, the
United States has undertaken an unprecedented building
program for new and improved water and wastewater treat-
ment systems. To date, much emphasis has been placed on
training engineers to plan, design, and construct treatment
facilities. At present, many programs in various engineer-
ing disciplines at many universities offer courses in water
and wastewater treatment plant design and operation.
This text is not about the planning, designing, or con-
struction of water and wastewater treatment facilities.
While these tasks are paramount to conception and con-
struction of needed facilities and needed infrastructure,
many excellent texts are available that cover these impor-
tant areas. This text is not about engineering at all. Instead,

it is about operations and is designed for the operator. We
often forget the old axiom: someone must build it, but
once built, someone must operate it. It is the operation of
“it” that concerns us here.
Several excellent texts have been written on water and
wastewater treatment plant operations. Thus, the logical
question is, why a new text covering a well-trodden road?
The compound answer is a text that is comprehensive
in scope, current, and deals with real world problems
involved with plant operations is needed. The simple
answer is that after September 11, things have changed.
Many of these changes were apparent before Septem-
ber 11; at the same time, many of our present needs were
not so apparent. Consider, for example, the need for plants
to become more efÞcient in operation and more economical
in practice. This is not new, but it now takes on added
importance because of the threat of privatization. We cover
privatization and the benchmarking process in this text.
On the other hand, how many of us thought security was
a big deal prior to September 11? Some of us did, while
some of us did not give it any thought at all. Today, things
are different; we must adjust or fall behind. In the present
climate, falling behind on the security of our potable water
supplies is not an option. We must aggressively protect
our precious water sources and those ancillaries that are
critical to maintaining and protecting water quality. We
cover plant security concerns in this text.
There are other current issues. For example, arsenic
in drinking water received a lot of coverage in the press
recently. We all know that arsenic is a deadly poison,

depending on dose, of course. Headlines stating that
arsenic has been found in certain municipal drinking water
supplies are a red ßag issue to many people. But is it really
an issue? We cover arsenic in drinking water in this text.
Another red ßag issue that has received some press
and the attention of regulators is the presence of patho-
genic protozoans, such as

Giardia

and

Cryptosporidium

,
in drinking water supplies. We cover both of these proto-
zoans in this text.
In wastewater treatment (as well as water treatment),
a lot of attention has been focused on disinfection by-
products in water efßuents outfalled into receiving water
bodies. We cover disinfection by-products in this text.
Water and wastewater treatment is about mitigating
the problems mentioned above. However, treatment oper-
ations are about much more. To handle today’s problems,
water and wastewater treatment system operators must be
generalists. Herein lies the problem. Many of the texts
presently available for water and wastewater operator use
are limited in scope and narrowly focused in content. Most
of these texts take a bare bones approach to presentation.
That is, the basics of each unit process are usually ade-

quately covered, but this is the extent of the coverage.
At present, available texts either ignore, avoid, or pay
cursory attention to such important areas as the multiple-
barrier concept, maintaining infrastructure, benchmarking,
plant security, operator roles, water hydraulics, microbi-
ology, water ecology, basic electrical principles, pumping,
conveyance, ßow measurement, basic water chemistry,
water quality issues, biomonitoring, sampling and testing,
water sources, and watershed protection. All of these
important topics are thoroughly discussed in

Handbook of
Water and Wastewater Treatment Plant Operations.

Though directed at water and wastewater operators,
this book will serve the needs of students; teachers; con-
© 2003 by CRC Press LLC

sulting engineers; and technical personnel in city, state,
and federal organizations who must review operations and
operating procedures. In order to maximize the usefulness
of the material contained in the test, it has been presented
in plain English in a simpliÞed and concise format. Many
tables have been developed, using a variety of sources.
To assure correlation to modern practice and design,
illustrative problems are presented in terms of commonly
used operational parameters.
Each chapter ends with a chapter review test to help
evaluate mastery of the concepts presented. Before going
on to the next chapter, take the review test, compare your

answers to the key provided in Appendix A, and review
the pertinent information for any problems you missed. If
you miss many items, review the whole chapter.
The indented notes displayed in various locations
throughout this text indicate or emphasize important
points to study carefully.
This text is accessible to those who have no experience
with water and wastewater operations. If you work
through the text systematically, you can acquire an under-
standing of and skill in water and wastewater operations.
This will add a critical component to your professional
knowledge.

Frank R. Spellman

Norfolk, VA
© 2003 by CRC Press LLC

Contents

PART IWater and Wastewater Operations: An Overview

Chapter 1Problems Facing Water and Wastewater Treatment Operations
1.1Introduction
1.2The Paradigm Shift
1.2.1A Change in the Way Things are Understood and Done
1.3Multiple-Barrier Concept
1.3.1Multiple-Barrier Approach: Wastewater Operations
1.4Management Problems Facing Water and Wastewater Operations
1.4.1Compliance with New, Changing, and Existing Regulations

1.4.2Maintaining Infrastructure
1.4.3Privatizing and/or Reengineering
1.4.4Benchmarking
1.4.4.1Benchmarking: The Process
1.4.5The Bottom Line on Privatization
1.5Upgrading Security
1.5.1The Bottom Line on Security
1.6Technical Management vs. Professional Management
1.7Chapter Review Questions and Problems
References
Chapter 2Water and Wastewater Operators and Their Roles
2.1Water and Wastewater Operators
2.2Setting the Record Straight
2.2.1The Computer-Literate Jack
2.2.2Plant Operators as Emergency Responders
2.2.3Operator Duties, Numbers, and Working Conditions
2.3Operator CertiÞcation/Licensure
2.4Chapter Review Questions and Problems
References
Chapter 3Water and Wastewater References, Models, and Terminology
3.1Setting the Stage
3.2Treatment Process Models
3.3Key Terms Used in Waterworks and Wastewater Operations
3.3.1Terminology and DeÞnitions
3.4Chapter Review Question and Problems
References
© 2003 by CRC Press LLC

PART IIWater/Wastewater Operations: Math and Technical Aspects

Chapter 4Water and Wastewater Math Operations
4.1Introduction
4.2Calculation Steps
4.3Table of Equivalents, Formulae, and Symbols
4.4Typical Water and Wastewater Math Operations
4.4.1Arithmetic Average (or Arithmetic Mean) and Median
4.4.2Ratio
4.4.3Percent
4.4.3.1Practical Percentage Calculations
4.4.4Units and Conversions
4.4.4.1Temperature Conversions
4.4.4.2Milligrams per Liter (Parts per Million)
4.5Measurements: Areas and Volumes
4.5.1Area of a Rectangle
4.5.2Area of a Circle
4.5.3Area of a Circular or Cylindrical Tank
4.5.4Volume Calculations
4.5.4.1Volume of Rectangular Tank
4.5.4.2Volume of a Circular or Cylindrical Tank
4.5.4.3Example Volume Problems
4.6Force, Pressure, and Head
4.7Flow
4.7.1Flow Calculations
4.7.1.1Instantaneous Flow Rates
4.7.1.2Flow through a Full Pipeline
4.7.2Velocity Calculations
4.7.3Average Flow Rate Calculations
4.7.4Flow Conversion Calculations
4.8Detention Time
4.8.1Hydraulic Detention Time

4.8.1.1Detention Time in Days
4.8.1.2Detention Time in Hours
4.8.1.3Detention Time in Minutes
4.9Chemical Dosage Calculations
4.9.1Chlorine Dosage
4.9.2Hypochlorite Dosage
4.10Percent Removal
4.11Population Equivalent or Unit Loading Factor
4.12SpeciÞc Gravity
4.13Percent Volatile Matter Reduction in Sludge
4.14Horsepower
4.14.1Water Horsepower
4.14.2Brake Horsepower
4.14.3Motor Horsepower
4.15Electrical Power
4.16Chemical Coagulation and Sedimentation
4.16.1Calculating Feed Rate
4.16.2Calculating Solution Strength
4.17Filtration
4.17.1Calculating the Rate of Filtration
4.17.2Filter Backwash
© 2003 by CRC Press LLC

4.18Practical Water Distribution System Calculations
4.18.1Water Flow Velocity
4.18.2Storage Tank Calculations
4.18.3Distribution System Disinfection Calculations
4.19Complex Conversions
4.19.1Concentration to Quantity
4.19.1.1Concentration (Milligrams per Liter) to Pounds

4.19.1.2Concentration (Milligrams per Liter) to Pounds/Day
4.19.1.3Concentration (Milligrams per Liter) to Kilograms per Day
4.19.1.4Concentration (milligrams/kilogram) to pounds/ton
4.19.2Quantity to Concentration
4.19.2.1Pounds to Concentration (Milligrams per Liter)
4.19.2.2Pounds per Day to Concentration (Milligrams per Liter)
4.19.2.3Kilograms per Day to Concentration (Milligrams per Liter)
4.19.3Quantity to Volume or Flow Rate
4.19.3.1Pounds to Tank Volume (Million Gallons)
4.19.3.2Pounds per Day to Flow (Million Gallons per Day)
4.19.3.3Kilograms per Day to Flow (Million Gallons per Day)
4.20Chapter Review Questions and Problems
Reference
Chapter 5Water Hydraulics
5.1What is Water Hydraulics?
5.2Basic Concepts
5.2.1Stevin’s Law
5.3Properties of Water
5.3.1Density and SpeciÞc Gravity
5.4Force and Pressure
5.4.1Hydrostatic Pressure
5.4.2Effects of Water under Pressure
5.5Head
5.5.1Static Head
5.5.2Friction Head
5.5.3Velocity Head
5.5.4Total Dynamic Head (Total System Head)
5.5.5Pressure/Head
5.5.6Head/Pressure
5.6Flow/Discharge Rate: Water in Motion

5.6.1Area/Velocity
5.6.2Pressure/Velocity
5.7Piezometric Surface and Bernoulli’s Theorem
5.7.1Law of Conservation of Energy
5.7.2Energy Head
5.7.3Piezometric Surface
5.7.3.1Head Loss
5.7.3.2Hydraulic Grade Line
5.7.4Bernoulli’s Theorem
5.7.4.1Bernoulli’s Equation
5.8Hydraulic Machines (Pumps)
5.8.1Pumping Hydraulics
5.9Well and Wet Well Hydraulics
5.9.1Well Hydraulics
5.9.2Wet Well Hydraulics
© 2003 by CRC Press LLC

5.10Friction Head Loss
5.10.1Flow in Pipelines
5.10.2Pipe and Open Flow Basics
5.10.3Major Head Loss
5.10.3.1Components of Major Head Loss
5.10.3.2Calculating Major Head Loss
5.10.4Minor Head Loss
5.11Basic Piping Hydraulics
5.11.1Piping Networks
5.11.1.1Energy Losses in Pipe Networks
5.11.1.2Pipes in Series
5.11.1.3Pipes in Parallel
5.12Open-Channel Flow

5.12.1Characteristics of Open-Channel Flow
5.12.1.1Laminar and Turbulent Flow
5.12.1.2Uniform and Varied Flow
5.12.1.3Critical Flow
5.12.1.4Parameters Used in Open-Channel Flow
5.12.2Open-Channel Flow Calculations
5.12.3Open-Channel Flow: The Bottom Line
5.13Flow Measurement
5.13.1Flow Measurement: The Old-Fashioned Way
5.13.2Basis of Traditional Flow Measurement
5.13.3Flow Measuring Devices
5.13.3.1Differential Pressure Flowmeters
5.13.3.2Magnetic Flowmeters
5.13.3.3Ultrasonic Flowmeters
5.13.3.4Velocity Flowmeters
5.13.3.5Positive-Displacement Flowmeters
5.13.4Open-Channel Flow Measurement
5.13.4.1Weirs
5.13.4.2Flumes
5.14Chapter Review Questions and Problems
References
Chapter 6Fundamentals of Electricity
6.1Electricity: What Is It?
6.2Nature of Electricity
6.3The Structure of Matter
6.4Conductors, Semiconductors, and Insulators
6.5Static Electricity
6.5.1Charged Bodies
6.5.2Coulomb’s Law
6.5.3Electrostatic Fields

6.6Magnetism
6.6.1Magnetic Materials
6.6.2Magnetic Earth
6.7Difference in Potential
6.7.1The Water Analogy
6.7.2Principal Methods of Producing Voltage
6.8Current
6.9Resistance
6.10Battery-Supplied Electricity
© 2003 by CRC Press LLC

6.10.1The Voltaic Cell
6.10.2Primary and Secondary Cells
6.10.3Battery
6.10.3.1Battery Operation
6.10.3.2Combining Cells
6.10.4Types of Batteries
6.10.4.1Dry Cell
6.10.4.2Lead-Acid Battery
6.10.4.3Alkaline Cell
6.10.4.4Nickel-Cadmium Cell
6.10.4.5Mercury Cell
6.10.4.6Battery Characteristics
6.11The Simple Electrical Circuit
6.11.1Schematic Representation
6.12Ohm’s law
6.13Electrical Power
6.13.1Electrical Power Calculations
6.14Electrical Energy
6.15Series DC Circuit Characteristics

6.15.1Series Circuit Resistance
6.15.2Series Circuit Current
6.15.3Series Circuit Voltage
6.15.4Series Circuit Power
6.15.5Summary of the Rules for Series DC Circuits
6.15.6General Series Circuit Analysis
6.15.6.1Kirchhoff’s Voltage Law
6.16Ground
6.17Open and Short Circuits
6.18Parallel DC Circuits
6.18.1Parallel Circuit Characteristics
6.18.2Voltage in Parallel Circuits
6.18.3Current in Parallel Circuits
6.18.4Parallel Circuits and Kirchhoff’s Current Law
6.18.5Parallel Circuit Resistance
6.18.5.1Reciprocal Method
6.18.5.2Product over the Sum Method
6.18.5.3Reduction to an Equivalent Circuit
6.18.6Power in Parallel Circuits
6.18.7Rules for Solving Parallel DC Circuits
6.19Series-Parallel Circuits
6.19.1Solving a Series-Parallel Circuit
6.20Conductors
6.20.1Unit Size of Conductors
6.20.1.1Square Mil
6.20.1.2Circular Mil
6.20.1.3Circular-Mil-Foot
6.20.1.4Resistivity
6.20.1.5Wire Measurement
6.20.2Factors Governing the Selection of Wire Size

6.20.2.1Copper vs. Other Metal Conductors
6.20.2.2Temperature CoefÞcient
6.20.3Conductor Insulation
6.20.4Conductor Splices and Terminal Connections
6.20.5Soldering Operations
© 2003 by CRC Press LLC

6.20.6Solderless Connections
6.20.7Insulation Tape
6.21Electromagnetism
6.21.1Magnetic Field around a Single Conductor
6.21.2Polarity of a Single Conductor
6.21.3Field around Two Parallel Conductors
6.21.4Magnetic Field of a Coil
6.21.4.1Polarity of an Electromagnetic Coil
6.21.4.2Strength of an Electromagnetic Field
6.21.5Magnetic Units
6.21.6Properties of Magnetic Materials
6.21.6.1Permeability
6.21.6.2Hysteresis
6.21.7Electromagnets
6.22AC Theory
6.22.1Basic AC Generator
6.22.1.1Cycle
6.22.1.2Frequency, Period, and Wavelength
6.22.2Characteristic Values of AC Voltage and Current
6.22.2.1Peak Amplitude
6.22.2.2Peak-to-Peak Amplitude
6.22.2.3Instantaneous Amplitude
6.22.2.4Effective or Root-Mean-Square Value

6.22.2.5Average Value
6.22.3Resistance in AC Circuits
6.22.4Phase Relationships
6.23Inductance
6.23.1Self-Inductance
6.23.2Mutual Inductance
6.23.3Calculation of Total Inductance
6.24Practical Electrical Applications
6.24.1Electrical Power Generation
6.24.2DC Generators
6.24.3AC Generators
6.24.4Motors
6.24.4.1DC Motors
6.24.4.2AC Motors
6.24.5Transformers
6.24.6Power Distribution System Protection
6.24.6.1Fuses
6.24.6.2Circuit Breakers
6.24.6.3Control Devices
6.25Chapter Review Questions and Problems
Chapter 7Hydraulic Machines: Pumps
7.1Introduction
7.2Archimedes’ Screw
7.3Pumping Hydraulics
7.3.1DeÞnitions
7.4Basic Principles of Water Hydraulics
7.4.1Weight of Air
7.4.2Weight of Water
7.4.3Weight of Water Related to the Weight of Air
7.4.4Water at Rest

© 2003 by CRC Press LLC

7.4.5Gauge Pressure
7.4.6Water in Motion
7.4.6.1Discharge
7.4.6.2The Law of Continuity
7.4.7Pipe Friction
7.5Basic Pumping Calculations
7.5.1Pumping Rates
7.5.2Calculating Head Loss
7.5.3Calculating Head
7.5.4Calculating Horsepower and EfÞciency
7.5.4.1Hydraulic Horsepower
7.5.4.2Pump EfÞciency and Brake Horsepower
7.5.5SpeciÞc Speed
7.6Pump Characteristic Curves
7.6.1Head-Capacity Curve
7.6.2The Power-Capacity Curve
7.6.3The EfÞciency-Capacity (E-Q) Curve
7.7Pumps in Series and Parallel
7.8Considerations for Pumping Wastewater
7.9Types of Pumps Used in Water and Wastewater Treatment
7.10Introduction to Centrifugal Pumps
7.10.1Description
7.10.2Theory
7.10.3Types of Centrifugal Pumps
7.10.3.1Radial Flow Impeller Pumps
7.10.3.2Mixed Flow Impeller Pumps
7.10.3.3Axial Flow Impeller Pumps (Propeller Pump)
7.10.4Characteristics and Performance Curves

7.10.4.1Head-Capacity Curve
7.10.4.2EfÞciency Curve
7.10.4.3Brake Horsepower Curves
7.10.5Advantages and Disadvantages of a Centrifugal Pump
7.10.5.1Advantages
7.10.5.2Disadvantages
7.10.6Water and Wastewater Applications
7.11Centrifugal Pump Components
7.11.1Casing
7.11.1.1Solid Casing
7.11.1.2Split Casings
7.11.2Impeller
7.11.2.1Semiopen Impeller
7.11.2.2Open Impeller
7.11.2.3Closed Impeller
7.11.3Wear Rings
7.11.4Shafts, Sleeves, and Couplings
7.11.4.1Shafting
7.11.4.2Sleeves
7.11.4.3Couplings
7.11.5StufÞng Box and Seals
7.11.5.1StufÞng Box or Packing Assembly
7.11.5.2Mechanical Seals
7.11.6Bearings
7.11.6.1Self-Aligning Double-Row Ball Bearing
7.11.6.2Single- or Double-Row Antifriction Ball Bearing
7.11.6.3Angular Contact Bearings
© 2003 by CRC Press LLC

7.11.6.4Self-Aligning Spherical Roller Bearings

7.11.6.5Single-Row Tapered Roller Bearings
7.11.6.6Bearing Installation, Maintenance and Lubrication
7.12Centrifugal Pump: Operational Procedures
7.12.1Installation
7.12.2Start-Up
7.12.2.1Start-Up Procedure
7.12.3Normal Operation
7.12.4Shutdown
7.12.5Priming
7.12.5.1Priming Procedure
7.12.6Backßushing
7.12.6.1Backßush Procedure
7.12.7Manual Removal Procedure
7.13Centrifugal Pump: Maintenance Procedures
7.13.1Pump and Motor Lubrication
7.13.2Packing and Seal Replacement
7.13.2.1Packing Procedure
7.13.2.2Mechanical Seal Installation Procedure
7.13.3Pump and Motor Bearing Inspection
7.13.4Shaft and Coupling Alignment
7.13.4.1Alignment Procedure
7.13.4.2Removal of Obstructions
7.14Centrifugal Pumps Preventive Maintenance
7.14.1Daily Maintenance
7.14.2Weekly Maintenance
7.14.3Monthly Maintenance
7.14.4Quarterly Maintenance
7.14.5Semiannual Maintenance
7.15Centrifugal Pump Lubrication
7.15.1Purpose of Lubrication

7.15.1.1Separates Surfaces
7.15.1.2Prevents Wear
7.15.1.3Cushions Shock
7.15.1.4Transfers Heat
7.15.1.5Corrosion Protection
7.15.1.6Protective Seal
7.15.2Lubrication Requirements
7.15.3Lubrication Procedures
7.15.3.1Motor Bearing Lubrication
7.15.3.2Pump Bearing Lubrication
7.16Centrifugal Pump: Troubleshooting
7.16.1The Troubleshooter
7.16.2Troubleshooting: What Is It?
7.16.3Goals of Troubleshooting
7.16.4The Troubleshooting Process
7.16.5Troubleshooting the Centrifugal Pump
7.16.5.1Pump Fails to Prime or Loses its Prime
7.16.5.2Pump Does Not Discharge
7.16.5.3Pump Does Not Deliver Rated Capacity
7.16.5.4Pump Does Not Deliver SufÞcient Pressure
7.16.5.5Pump Starts and Stops Pumping
7.16.5.6Pump Overloads Driver or Consumes Excessive Power
7.16.5.7Pump Is Noisy or Has Extensive Vibration
7.16.5.8Packing Has a Short Life
© 2003 by CRC Press LLC

7.16.5.9Mechanical Seal Has a Short Life
7.16.5.10Mechanical Seal Leaks Excessively
7.16.5.11Bearings Have a Short Life
7.16.5.12Pump Overheats or Seizes

7.17Centrifugal Pump ModiÞcations
7.17.1Submersible Pumps
7.17.1.1Applications
7.17.1.2Advantages
7.17.1.3Disadvantages
7.17.2Recessed Impeller or Vortex Pumps
7.17.2.1Applications
7.17.2.2Advantages
7.17.2.3Disadvantages
7.17.3Turbine Pumps
7.17.3.1Application
7.17.3.2Advantages
7.17.3.3Disadvantages
7.18Positive-Displacement Pumps
7.18.1Reciprocating Pumps
7.18.1.1Diaphragm Pumps
7.18.1.2Metering Pumps
7.18.1.3Rotary Pumps
7.18.1.4Progressive-Cavity Pump
7.18.1.5Special Purpose Pumps
7.19Chapter Review Questions and Problems
References
Chapter 8Water and Wastewater Conveyance
8.1Delivering the Lifeblood of Civilization
8.2Conveyance Systems
8.2.1DeÞnitions
8.2.2Fluids vs. Liquids
8.2.3Maintaining Fluid Flow in Piping Systems
8.2.3.1Scaling
8.2.4Piping System Maintenance

8.2.5Valves
8.2.6Piping System Accessories
8.2.7Piping Systems: Temperature Effects
8.2.8Piping Systems: Insulation
8.3Metallic Piping
8.3.1Piping Materials
8.3.2Piping: The Basics
8.3.2.1Pipe Sizes
8.3.2.2Pipe Wall Thickness
8.3.2.3Piping ClassiÞcation
8.3.3Types of Piping Systems
8.3.3.1Code for IdentiÞcation of Pipelines
8.3.4Metallic Piping Materials
8.3.4.1Characteristics of Metallic Materials
8.3.5Maintenance Characteristics of Metallic Piping
8.3.5.1Expansion and Flexibility
8.3.5.2Pipe Support Systems
8.3.5.3Valve Selection
8.3.5.4Isolation
© 2003 by CRC Press LLC

8.3.5.5Preventing Backßow
8.3.5.6Water Hammer
8.3.5.7Air Binding
8.3.5.8Corrosion Effects
8.3.6Joining Metallic Pipe
8.3.6.1Bell-and-Spigot Joints
8.3.6.2Screwed or Threaded Joints
8.3.6.3Flanged Joints
8.3.6.4Welded Joints

8.3.6.5Soldered and Brazed Joints
8.4Nonmetallic Piping
8.4.1Nonmetallic Piping Materials
8.4.1.1Clay Pipe
8.4.1.2Concrete Pipe
8.4.1.3Plastic Pipe
8.5Tubing
8.5.1Tubing vs. Piping: The Difference
8.5.1.1Tubing
8.5.2Advantages of Tubing
8.5.2.1Tubing: Mechanical Advantages
8.5.2.2Chemical Advantages
8.5.3Connecting Tubing
8.5.3.1Cutting Tubing
8.5.3.2Soldering Tubing
8.5.3.3Connecting Flared/Nonßared Joints
8.5.4Bending Tubing
8.5.5Types of Tubing
8.5.5.1Typical Tubing Applications
8.6Industrial Hoses
8.6.1Hose Nomenclature
8.6.2Factors Governing Hose Selection
8.6.3Standards, Codes, and Sizes
8.6.3.1Hose Size
8.6.4Hose ClassiÞcations
8.6.4.1Nonmetallic Hoses
8.6.4.2Metallic Hoses
8.6.5Hose Couplings
8.6.6Hose Maintenance
8.7Pipe and Tube Fittings

8.7.1Fittings
8.7.2Functions of Fittings
8.7.2.1Changing the Direction of Flow
8.7.2.2Providing Branch Connections
8.7.2.3Changing the Sizes of Lines
8.7.2.4Sealing Lines
8.7.2.5Connecting Lines
8.7.3Types of Connections
8.7.3.1Screwed Fittings
8.7.3.2Flanged Connections
8.7.3.3Connections
8.7.4Tubing Fittings and Connections
8.8Valves
8.8.1Valve Construction
8.8.2Types of Valves
© 2003 by CRC Press LLC

8.8.2.1Ball Valves
8.8.2.2Gate Valves
8.8.2.3Globe Valves
8.8.2.4Needle Valves
8.8.2.5Butterßy Valves
8.8.2.6Plug Valves
8.8.2.7Check Valves
8.8.2.8Quick-Opening Valves
8.8.2.9Diaphragm Valves
8.8.2.10Regulating Valves
8.8.2.11Relief Valves
8.8.2.12Reducing Valves
8.8.3Valve Operators

8.8.3.1Pneumatic and Hydraulic Valve Operators
8.8.3.2Magnetic Valve Operators
8.8.4Valve Maintenance
8.9Piping System: Protective Devices
8.9.1Applications
8.9.2Strainers
8.9.3Filters
8.9.4Traps
8.9.4.1Trap Maintenance and Testing
8.10Piping Ancillaries
8.10.1Gauges
8.10.1.1Pressure Gauges
8.10.2Vacuum Breakers
8.10.3Accumulators
8.10.4Air Receivers
8.10.5Heat Exchangers
8.11Chapter Review Questions and Problems
References
Chapter 9Flow Measurement
9.1Introduction
9.2Methods of Measuring Flow
9.2.1Weirs
9.2.2The Oscillating Disk Water Meter
9.2.3Flumes
9.2.4Venturi Meter
9.2.5Magnetic Flowmeter
9.3Flow Measurement Calculations
9.3.1Calculation Method Used for Fill and Draw Technique
9.3.2Calculation Method Used for Velocity/Area Technique
9.3.3Calculation Method Used for V-Notch Weirs

9.3.4Weir Overßow (Weir Loading Rate)
9.3.5Calculation Method for Parshall Flume
9.3.6Typical Flow Measurement Practice Calculations
9.4Flow Measurement Operational Problems
9.5Chapter Review Questions and Problems
References
© 2003 by CRC Press LLC

Part IIICharacteristics of Water

Chapter 10Basic Water Chemistry
10.1Introduction
10.2Chemistry Concepts and DeÞnitions
10.2.1Concepts
10.2.2DeÞnitions
10.3Water Chemistry Fundamentals
10.3.1Matter
10.3.1.1The Content of Matter: The Elements
10.3.2Compound Substances
10.4The Water Molecule
10.5Water Solutions
10.6Water Constituents
10.6.1Solids
10.6.2Turbidity
10.6.3Color
10.6.4Dissolved Oxygen
10.6.5Metals
10.6.6Organic Matter
10.6.7Inorganic Matter
10.6.7.1Acids

10.6.7.2Bases
10.6.7.3Salts
10.7pH
10.8Alkalinity
10.9Hardness
10.10Water and Wastewater Chemicals and Chemical Processes
10.10.1Odor Control (Wastewater Treatment)
10.10.2Disinfection
10.10.3Chemical Precipitation
10.10.4Adsorption
10.10.5Coagulation
10.10.6Taste and Odor Removal
10.10.7Water Softening
10.10.8Recarbonation
10.10.9Ion Exchange Softening
10.10.10Scaling and Corrosion Control
10.11Chapter Review Questions and Problems
References
Chapter 11Water Microbiology
11.1Introduction
11.2Microbiology: What Is It?
11.3Water and Wastewater Microorganisms
11.3.1Key Terms
11.3.2Microorganisms (in General)
11.3.3ClassiÞcation
11.3.4Differentiation
11.3.5The Cell
11.3.5.1Structure of the Bacterial Cell
© 2003 by CRC Press LLC

11.4Bacteria
11.4.1Bacterial Growth Factors
11.4.2Destruction of Bacteria
11.4.3Waterborne Bacteria
11.5Protozoa
11.6Microscopic Crustaceans
11.7Viruses
11.8Algae
11.9Fungi
11.10Nematodes and Flatworms (Worms)
11.11Pathogenic Protozoa and Helminths (Water)
11.11.1Pathogenic Protozoa
11.11.1.1

Giardia

11.11.1.2

Cryptosporidium

11.11.1.3

Cyclospora

11.11.2Helminths
11.12Biological Aspects and Processes (Wastewater)
11.12.1Aerobic Process
11.12.2Anaerobic Process
11.12.3Anoxic Process
11.12.4Photosynthesis

11.12.5Growth Cycles
11.12.6Biogeochemical Cycles
11.12.6.1Carbon Cycle
11.12.6.2Nitrogen Cycle
11.12.6.3Sulfur Cycle
11.12.6.4Phosphorus Cycle
11.13Chapter Review Questions and Problems
References
Chapter 12Water Ecology
12.1Introduction
12.2Setting the Stage
12.3Ecology Terms
12.3.1DeÞnition of Terms
12.4Levels of Organization
12.5Ecosystem
12.6Energy Flow in the Ecosystem
12.7Food Chain EfÞciency
12.8Ecological Pyramids
12.9Productivity
12.10Population Ecology
12.11Stream Genesis and Structure
12.11.1Water Flow in a Stream
12.11.2Stream Water Discharge
12.11.3Transport of Material
12.11.4Characteristics of Stream Channels
12.11.5Stream ProÞles
12.11.6Sinuosity
12.11.7Bars, Rifßes, and Pools
12.11.8The Floodplain
12.11.9Adaptations to Stream Current

© 2003 by CRC Press LLC

12.11.10Types of Adaptive Changes
12.11.11SpeciÞc Adaptations
12.12Benthic Life: An Overview
12.12.1Benthic Plants and Animals
12.13Benthic Macroinvertebrates
12.13.1IdentiÞcation of Benthic Macroinvertebrates
12.13.2Macroinvertebrates and the Food Web
12.13.3Units of Organization
12.13.4Typical Running Water Benthic Macroinvertebrates
12.14Insect Macroinvertebrates
12.14.1Mayßies (Order: Ephemeroptera)
12.14.2Stoneßies (Order: Plecoptera)
12.14.3Caddisßies (Order: Trichoptera)
12.14.4True Flies (Order: Diptera)
12.14.5Beetles (Order: Coleoptera)
12.14.6Water Strider (Jesus bugs; Order: Hemiptera)
12.14.7Alderßies and Dobsonßies (Order: Megaloptera)
12.14.8Dragonßies and Damselßies (Order: Odonata)
12.15Noninsect Macroinvertebrates
12.15.1Oligochaeta (Family: TuiÞcidae; Genus: Tubifex)
12.15.2Hirudinea (Leeches)
12.14.3Gastropoda (Lung-Breathing Snail)
12.16Chapter Review Questions and Problems
References
Chapter 13Water Quality
13.1Introduction
13.2The Water Cycle
13.3Water Quality Standards

13.3.1Clean Water Act (1972)
13.3.2Safe Drinking Water Act (1974)
13.4Water Quality Characteristics of Water and Wastewater
13.4.1Physical Characteristics of Water and Wastewater
13.4.1.1Solids
13.4.1.2Turbidity
13.4.1.3Color
13.4.1.4Taste and Odor
13.4.1.5Temperature
13.4.2Chemical Characteristics of Water
13.4.2.1Total Dissolved Solids (TDS)
13.4.2.2Alkalinity
13.4.2.3Hardness
13.4.2.4Fluoride
13.4.2.5Metals
13.4.2.6Organics
13.4.2.7Nutrients
13.4.3Chemical Characteristics of Wastewater
13.4.3.1Organic Substances
13.4.3.2Inorganic Substances
13.4.4Biological Characteristics of Water and Wastewater
13.4.4.1Bacteria
13.4.4.2Viruses
13.4.4.3Protozoa
13.4.4.4Worms (Helminths)
© 2003 by CRC Press LLC

13.5Chapter Review Questions and Problems
References
Chapter 14Biomonitoring, Monitoring, Sampling, and Testing

14.1What Is Biomonitoring?
14.1.1Biotic Indices (Streams)
14.1.1.1Benthic Macroinvertebrate Biotic Index
14.2Biological Sampling (Streams)
14.2.1Biological Sampling: Planning
14.2.2Sampling Stations
14.2.3Sample Collection
14.2.3.1Macroinvertebrate Sampling Equipment
14.2.3.2Macroinvertebrate Sampling: Rocky-Bottom Streams
14.2.3.3Macroinvertebrate Sampling: Muddy-Bottom Streams
14.2.4Postsampling Routine
14.2.4.1Sampling Devices
14.2.5The Bottom Line on Biological Sampling
14.3Water Quality Monitoring (Drinking Water)
14.3.1Is the Water Good or Bad?
14.3.2State Water Quality Standards Programs
14.3.3Designing a Water Quality Monitoring Program
14.3.4General Preparation and Sampling Considerations
14.3.4.1Method A: General Preparation of Sampling Containers
14.3.4.2Method B: Acid Wash Procedures
14.3.5Sample Types
14.3.6Collecting Samples from a Stream
14.3.6.1Whirl-pak® Bags
14.3.6.2Screw-Cap Bottles
14.3.7Sample Preservation and Storage
14.3.8Standardization of Methods
14.4Test Methods (Drinking Water and Wastewater)
14.4.1Titrimetric Methods
14.4.2Colorimetric Methods
14.4.3Visual Methods

14.4.4Electronic Methods
14.4.5Dissolved Oxygen Testing
14.4.5.1Sampling and Equipment Considerations
14.4.5.2Dissolved Oxygen Test Methods
14.4.6Biochemical Oxygen Demand Testing
14.4.6.1Sampling Considerations
14.4.6.2BOD Sampling, Analysis, and Testing
14.4.7Temperature Measurement
14.4.7.1Sampling and Equipment Considerations
14.4.8Hardness Measurement
14.4.8.1Measuring Hardness
14.4.9pH Measurement
14.4.9.1Analytical and Equipment Considerations
14.4.9.2pH Meters
14.4.9.3pH Pocket Pals and Color Comparators
© 2003 by CRC Press LLC

14.4.10Turbidity Measurement
14.4.10.1Sampling and Equipment Considerations
14.4.10.2Using a Secchi Disk
14.4.10.3Transparency Tube
14.4.11Orthophosphate Measurement
14.4.11.1Forms of Phosphorus
14.4.11.2The Phosphorus Cycle
14.4.11.3Testing Phosphorus
14.4.11.4Sampling and Equipment Considerations
14.4.11.5Ascorbic Acid Method for Determining Orthophosphate
14.4.12Nitrates Measurement
14.4.12.1Sampling and Equipment Considerations
14.4.12.2Cadmium Reduction Method

14.4.12.3Nitrate Electrode Method
14.4.13Solids Measurement
14.4.13.1Solids Sampling and Equipment Considerations
14.4.13.2Total Suspended Solids
14.4.13.3Volatile Suspended Solids Testing
14.4.14Conductivity Testing
14.4.14.1Sampling, Testing, and Equipment Considerations
14.4.15Total Alkalinity
14.4.15.1Analytical and Equipment Considerations
14.4.15.2Burets, Titrators, and Digital Titrators for Measuring Alkalinity
14.4.16Fecal Coliform Bacteria Testing
14.4.16.1Fecal Coliforms: General Information
14.4.16.2Fecal Coliforms
14.4.16.3Sampling Requirements
14.4.16.4Sampling and Equipment Considerations
14.4.16.5Fecal Coliform Testing
14.4.17Apparent Color Testing/Analysis
14.4.18Odor Analysis of Water
14.4.19Chlorine Residual Testing/Analysis
14.4.19.1DPD-Spectrophotometric
14.4.19.2DPD-FAS Titration
14.4.19.3Titrimetric–Amperometric Direct Titration
14.4.20Fluorides
14.5Chapter Review Questions and Problems
References

Part IVWater and Water Treatment

Chapter 15Potable Water Sources
15.1Introduction

15.1.1Key Terms and DeÞnitions
15.1.2Hydrologic Cycle
15.2Sources of Water
15.3Surface Water
15.3.1Advantages and Disadvantages of Surface Water
15.3.2Surface Water Hydrology
15.3.3Raw Water Storage
15.3.4Surface Water Intakes
15.3.5Surface Water Screens
15.3.6Surface Water Quality
© 2003 by CRC Press LLC

15.4Groundwater
15.4.1Groundwater Quality
15.5GUDISW
15.6Surface Water Quality and Treatment Requirements
15.7Public Water System Use Requirements
15.8Well Systems
15.8.1Well Site Requirements
15.8.2Types of Wells
15.8.2.1Shallow Wells
15.8.2.2Deep Wells
15.8.3Components of a Well
15.8.3.1Well Casing
15.8.3.2Grout
15.8.3.3Well Pad
15.8.3.4Sanitary Seal
15.8.3.5Well Screen
15.8.3.6Casing Vent
15.8.3.7Drop Pipe

15.8.3.8Miscellaneous Well Components
15.8.4Well Evaluation
15.8.5Well Pumps
15.8.6Routine Operation and Record Keeping Requirements
15.8.6.1Well Log
15.8.7Well Maintenance
15.8.7.1Troubleshooting Well Problems
15.8.8Well Abandonment
15.9Chapter Review Questions and Problems
Reference
Chapter 16Watershed Protection
16.1Introduction
16.2Current Issues in Water Management
16.3What is a Watershed?
16.4Water Quality Impact
16.5Watershed Protection and Regulations
16.6A Watershed Protection Plan
16.7Reservoir Management Practices
16.8Watershed Management Practices
16.9Chapter Review Questions and Problems
Reference
Chapter 17Water Treatment Operations and Unit Processes
17.1Introduction
17.2Waterworks Operators
17.3Purpose of Water Treatment
17.4Stages of Water Treatment
17.5Pretreatment
17.5.1Aeration
17.5.2Screening
17.5.3Chemical Addition

17.5.3.1Chemical Solutions
17.5.3.2Chemical Feeders
17.5.3.3Chemical Feeder Calibration
© 2003 by CRC Press LLC

17.5.3.4Iron and Manganese Removal
17.5.3.5Hardness Treatment
17.5.3.6Corrosion Control
17.6Coagulation
17.6.1Jar Testing Procedure
17.7Flocculation
17.8Sedimentation
17.9Filtration
17.9.1Types of Filter Technologies
17.9.1.1Slow Sand Filters
17.9.1.2Rapid Sand Filters
17.9.1.3Pressure Filter Systems
17.9.1.4Diatomaceous Earth Filters
17.9.1.5Direct Filtration
17.9.1.6Alternate Filters
17.9.2Common Filter Problems
17.9.3Filtration and Compliance with Turbidity Requirements (IESWTR)
17.9.3.1Regulatory Requirements
17.9.3.2Individual Filter Monitoring
17.9.3.3Reporting and Record Keeping
17.9.3.4Additional Compliance Issues
17.10Disinfection
17.10.1Need for Disinfection in Water Treatment.
17.10.2Pathogens of Primary Concern
17.10.2.1Bacteria

17.10.2.2Viruses
17.10.2.3Protozoa
17.10.3Recent Waterborne Outbreaks
17.10.3.1

E. coli

17.10.3.2

Giardia lamblia

17.10.3.3

Cryptosporidium

17.10.3.4

Legionella pneumophila

17.10.4Mechanism of Pathogen Inactivation
17.10.5Other Uses of Disinfectants in Water Treatment
17.10.5.1Minimization of DBP Formation
17.10.5.2Control of Nuisance Asiatic Clams and Zebra Mussels
17.10.5.3Oxidation of Iron and Manganese
17.10.5.4 Prevention of Regrowth in the Distribution System and Maintenance of
Biological Stability
17.10.5.5Removal of Taste and Odors through Chemical Oxidation
17.10.5.6Improvement of Coagulation and Filtration EfÞciency
17.10.5.7Prevention of Algal Growth in Sedimentation Basins and Filters
17.10.5.8Removal of Color

17.10.6Types of DBPs and Disinfection Residuals
17.10.6.1Disinfection By-Product Formation
17.10.6.2DBP Control Strategies
17.10.6.3CT Factor
17.10.7Pathogen Inactivation vs. DBP Formation
17.10.8Disinfectant Residual Regulatory Requirements
17.10.9Summary of Current National Disinfection Practices
17.10.10Summary of Methods of Disinfection
17.10.11Chlorination
17.10.11.1Chlorine Terms
17.10.11.2Chlorine Chemistry
17.10.11.3Breakpoint Chlorination
© 2003 by CRC Press LLC

17.10.11.4Gas Chlorination
17.10.11.5Hypochlorination
17.10.11.6Determining Chlorine Dosage
17.10.11.7Chlorine Generation
17.10.11.8Primary Uses and Points of Application of Chlorine
17.10.11.9Factors Affecting Chlorination
17.10.11.10Measuring Chlorine Residual
17.10.11.11Pathogen Inactivation and Disinfection EfÞcacy
17.10.11.12Disinfection By-Products
17.10.11.13Operational Considerations
17.10.11.14Advantages and Disadvantagesof Chlorine Use
17.10.11.15Chlorine Summary Table
17.11Arsenic Removal from Drinking Water
17.11.1Arsenic and Water
17.11.2Arsenic Removal Technologies
17.11.2.1Prescriptive Processes

17.11.2.2Adsorptive Processes
17.11.2.3Membrane Processes
17.11.2.4Alternative Technologies
17.12Who is Ultimately Responsible for Drinking Water Quality?
17.13Chapter Review Questions and Problems
References
Chapter 18Wastewater Treatment
18.1Wastewater Operators
18.1.1The Wastewater Treatment Process: The Model
18.2Wastewater Terminology and DeÞnitions
18.2.1Terminology and DeÞnitions
18.3Measuring Plant Performance
18.3.1Plant Performance and EfÞciency
18.3.2Unit Process Performance and EfÞciency
18.3.3Percent Volatile Matter Reduction in Sludge
18.4Hydraulic Detention Time
18.4.1Detention Time in Days
18.4.2Detention Time in Hours
18.4.3Detention Time in Minutes
18.5Wastewater Sources and Characteristics
18.5.1Wastewater Sources
18.5.1.1Generation of Wastewater
18.5.2ClassiÞcation of Wastewater
18.5.3Wastewater Characteristics
18.5.3.1Physical Characteristics
18.5.3.2Chemical Characteristics
18.5.3.3Biological Characteristics and Processes
18.6Wastewater Collection Systems
18.6.1Gravity Collection System
18.6.2Force Main Collection System

18.6.3Vacuum System
18.6.4Pumping Stations
18.6.4.1Wet Well–Dry Well Pumping Stations
18.6.4.2Wet Well Pumping Stations
18.6.4.3Pneumatic Pumping Stations
18.6.4.4Pumping Station Wet Well Calculations
© 2003 by CRC Press LLC

18.7Preliminary Treatment
18.7.1Screening
18.7.1.1Manually Cleaned Screens
18.7.1.2Mechanically Cleaned Screens
18.7.1.3Safety
18.7.1.4Screenings Removal Computations
18.7.2Shredding
18.7.2.1Comminution
18.7.2.2Barminution
18.7.3Grit Removal
18.7.3.1Gravity and Velocity Controlled Grit Removal
18.7.3.2Grit Removal Calculations
18.7.4Preaeration
18.7.4.1Operational Observations, Problems, and Troubleshooting
18.7.5Chemical Addition
18.7.5.1Operational Observations, Problems, and Troubleshooting
18.7.6Equalization
18.7.6.1Operational Observations, Problems, andTroubleshooting
18.7.7Aerated Systems
18.7.8Cyclone Degritter
18.7.9Preliminary Treatment Sampling and Testing
18.7.10Other Preliminary Treatment Process Control Calculations

18.8Primary Treatment (Sedimentation)
18.8.1Process Description
18.8.1.1Overview of Primary Treatment
18.8.2Types of Sedimentation Tanks
18.8.2.1Septic Tanks
18.8.2.2Two-Story (Imhoff) Tank
18.8.2.3Plain Settling Tanks (ClariÞers)
18.8.3Operator Observations, Process Problems, and Troubleshooting
18.8.3.1Primary ClariÞcation: Normal Operation
18.8.3.2Primary ClariÞcation: Operational Parameters (Normal Observations)
18.8.4Process Control Calculations
18.8.4.1Percent Removal
18.8.4.2Detention Time
18.8.4.3Surface Loading Rate (Surface Settling Rate and Surface Overßow Rate)
18.8.4.4Weir Overßow Rate (Weir Loading Rate)
18.8.4.5Sludge Pumping
18.8.4.6BOD and Suspended Solids Removal
18.8.5Problem Analysis
18.8.6Efßuent from Settling Tanks
18.9Secondary Treatment
18.9.1Treatment Ponds
18.9.1.1Types of Ponds
18.9.1.2Process Control Calculations (Stabilization Ponds)
18.9.2Trickling Filters
18.9.2.1Trickling Filter DeÞnitions
18.9.2.2Trickling Filter Equipment
18.9.2.3Filter ClassiÞcations
18.9.2.4Standard Operating Procedures
18.9.2.5General Process Description
18.9.2.6Operator Observations, Process Problems, and Troubleshooting

18.9.2.7Process Calculations
© 2003 by CRC Press LLC

18.9.3Rotating Biological Contactors
18.9.3.1RBC Equipment
18.9.3.2RBC Operation
18.9.3.3RBC: Expected Performance
18.9.3.4Operator Observations, Process Problems, and Troubleshooting
18.9.3.5RBC: Process Control Calculations
18.10Activated Sludge
18.10.1Activated Sludge Terminology
18.10.2Activated Sludge Process: Equipment
18.10.2.1Aeration Tank
18.10.2.2Aeration
18.10.2.3Settling Tank
18.10.2.4Return Sludge
18.10.2.5Waste Sludge
18.10.3Overview of Activated Sludge Process
18.10.4Activated Sludge Process: Factors Affecting Operation
18.10.4.1Growth Curve
18.10.5Activated Sludge Formation
18.10.6Activated Sludge: Performance-Controlling Factors
18.10.6.1Aeration
18.10.6.2Alkalinity
18.10.6.3Nutrients
18.10.6.4pH
18.10.6.5Temperature
18.10.6.6Toxicity
18.10.6.7Hydraulic Loading
18.10.6.8Organic Loading

18.10.7Activated Sludge ModiÞcations
18.10.7.1Conventional Activated Sludge
18.10.7.2Step Aeration
18.10.7.3Complete Mix
18.10.7.4Pure Oxygen
18.10.7.5Contact Stabilization
18.10.7.6Extended Aeration
18.10.7.7Oxidation Ditch
18.10.8Activated Sludge: Process Control Parameters
18.10.8.1Alkalinity
18.10.8.2Dissolved Oxygen
18.10.8.3pH
18.10.8.4 Mixed Liquor Suspended Solids, Mixed Liquor Volatile Suspended Solids,
and Mixed Liquor Total Suspended Solids
18.10.8.5Return Activated Sludge Rate and Concentration
18.10.8.6Waste Activated Sludge Flow Rate
18.10.8.7Temperature
18.10.8.8Sludge Blanket Depth
18.10.9Operational Control Levels
18.10.9.1Inßuent Characteristics
18.10.9.2Industrial Contributions
18.10.9.3Process Sidestreams
18.10.9.4Seasonal Variations
18.10.9.5Control Levels at Start-Up
18.10.10Operator Observations: Inßuent and Aeration Tank
18.10.10.1Visual Indicators: Inßuent and Aeration Tank
18.10.10.2Final Settling Tank (ClariÞer) Observations
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