800R80908
DEVELOPMENT OP A FIELD STUDY EDUCATIONAL PROGRAM
FOR WASTEWATER TREATMENT PLANT OPERATORS
ABSTRACT
Administrators who wish to improve the operation of
wastewater treatment plants under their management can make
good use of the instructional materials described in this
paper. A manual entitled Operation of Wastewater Treatment
Plants was developed for use by individual or group study.
Experienced operators wrote the material for operating
personnel who have not had the benefit of specialized
education in wastewater treatment facility operation. A
three phase developmental program is described which defines
tasks and routines of daily plant operation, checks these
under on-site in-plant conditions and edits and reviews
material for instructional purposes by individuals concerned
with personnel training and plant operation. The instruc-
tional materials are intended to assist training operators
in the specialized responsibilities needed in daily treatment
plant operations and to encourage them to develop themselves
and their capabilities into better plant operators.
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DEVELOPMENT OP A FIELD STUDY EDUCATIONAL PROGRAM
FOR WASTEWATER TREATMENT PLANT OPERATORS
INTRODUCTION
Administrators who wish to improve the operation of
wastewater treatment plants under their management can make
good use of instructional materials described in this paper.
Also important to the administrator is an understanding of
how the materials were developed and verified so that he can
evaluate their applicability to his particular situation.
Included is a history of how a new field study manual
entitled Operation of Wastewater Treatment Plants was
written, applied, evaluated and rewritten into its current
form.
NEED FOR FIELD STUDY EDUCATIONAL PROGRAM
Proper operation of wastewater treatment facilities is
essential to accomplish the intended purpose of the plant.
Educational institutions have stressed curriculums preparing
students for professional practice in the fields of process
research and design of wastewater treatment plants, but
frequently the operation of treatment facilities is virtually
ignored. Many operators have not received an adequate education
to understand the complexities of successful plant operation.
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Reasons for inadequate education include the lack of
proper educational materials and facilities. Other factors
contributing to the problem include public apathy, insuffi-
cient qualified training instructors, and the desire of many
individuals and agencies to develop their own educational
materials. To some extent specialized material is necessary
to include unique local problems and regulatory requirements.
This program contains the basic information essential for
all programs. A group instructor or field study (correspon-
dence course) administrator can use this material plus any
specialty information and organizational structures pertinent
to his area. A pattern is provided for one area as a model
for others.
INSTRUCTIONAL OBJECTIVE
Development of capable, trained personnel who can
operate wastewater treatment plants efficiently is the
objective of this educational program. Efficiency is defined
in terms of producing a high quality effluent as intended by
the plant designer, meeting established receiving water
quality standards, and minimizing costs of operation. Accom-
plishment of the objective can be greatly assisted by
providing operators with the knowledge and procedures they
need for efficient operation of wastewater treatment
facilities.
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IDENTIFICATION OF ESSENTIAL KNOWLEDGE AND PROCEDURES
Experienced operators were requested to write the infor-
mation and procedures they felt an operator needed to know to
operate his plant. Site visits to various types of wastewater
treatment plants were conducted to observe the situations
encountered by operators and their daily operational problems.
Special attention was given to plant start-up, daily opera-
tional schedule, frequently encountered problems, maintenance,
sample collection and analysis, and operator response to lab
results.
REVIEW AND SELECTION OF EDUCATIONAL METHODS
A team of experienced operators, consulting engineers,
administrators, regulatory personnel, and educators was formed
to develop a curriculum capable of accomplishing the objective
of this program. How to best convey the desired information
and procedures to operators unable to attend conventional
classroom programs was the next problem to be solved. For
the program to be readily available to as many operators as
possible, the cost should be as low as possible without
sacrificing the transfer of knowledge. Correspondence schools,
home study, and self-study manuals have been used extensively
in this type of situation in the past.
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Correspondence schools for wastewater treatment plant
operators sponsored by International Correspondence School,
Clemson University and University of Arizona were examined.
Erdos (6) provides considerable insight to all aspects of
a correspondence program in a UNESCO source book. U.S. Navy
training course manuals for Water and Sewage Plant Operators
(20) and the excellent manuals of practice published by the
Water Pollution Control Federation (11) were reviewed. Very
good textbooks on the operation of wastewater treatment plants
that were studied include the "Texas Manual" (10), "New York
Manual" (9), and a publication by Bloodgood (3). Techniques
used in DuPont (lp) and other self-study manuals (2, 18) were
carefully studied. Persons actively developing self-study
manuals using programmed learning techniques were interviewed
(16, 19) and research reported by the Educational Research
and Methods Division of the American Society for Engineering
Education (5) was thoroughly reviewed. Innovative audio-
visual techniques (1, 7, 13) were examined for potential use
by operators.
Programmed instruction techniques were selected as the
most appropriate means of conveying the desired knowledge
because no additional facilities or material other than the
basic manual would be required. Other methods might be more
effective, but the limited budgets of small agencies and
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income of their operators could preclude the purchase of any
special facilities.
A strict programmed instruction lesson is classified as
either a linear (12, 1?) or a branched type (19). In a
linear type, the student covers a portion of the page with a
piece of paper as he reads the lesson. Whenever he comes to
a blank space or a question, he thinks or writes his answer,
uncovers the correct answer, and checks his result. A
branched program consists of questions with multiple choice
answers. The student reads a short section in the lesson and
then encounters a question. He selects what appears to him
to be the correct answer. Then he is instructed to turn to a
specific page where he is informed whether his answer is
correct or not and where to read next, depending on his answer,
Strict adherence to either programmed instruction tech-
nique requires considerable time and ingenuity to develop the
instructional material. Neither approach is familiar to most
operators, although they could adapt to the procedure. Pre-
sentation of material on the operation of wastewater treatment
plants by either technique limits the value of the material
for quick and easy reference when olant operational problems
occur. To overcome these shortcomings of strict programmed
instruction, the material was arranged in the form of a
typical textbook but presented using the techniques of pro-
grammed instruction.
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Tests by educators and psychologists have indicated that
answering questions immediately after reading the material
provides immediate reinforcement of knowledge. Research with
equivalent groups using programmed instruction indicates that
essay and multiple choice questions are equally effective;
however, retention is much better one year later in groups
using essay questions. The adopted procedure was for the
operator to read a short section (1 to 5 pages), write the
answer to a few questions (1 to 5>)» compare his answers with
suggested answers at the end of the chapter, and decide
whether to reread the short section or continue on to the
next section. A major advantage of this approach is that an
operator can precede at his own pace and operators with
considerable variations in education and experience all can
use the material.
PREPARATION OF MATERIAL
Information and procedures needed by operators of waste-
water treatment plants was divided into seventeen chapters on
the basis of subject matter as shown in Table I. Experienced
wastewater treatment plant operators wrote the chapters on
treatment plant processes with emphasis on what the operator
needed to know to perform his duties effectively. Each treat-
ment process chapter followed the format outlined in Table II,
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After the writers of each chapter had prepared their
material, it was reviewed, edited, and rewritten in the
selected programmed instruction format. Following each short
section of a particular topic, several questions were prepared
for the operator to answer. These questions were designed to
reflect problems an operator could encounter and attempted
to obtain a solution from the operator that he could apply to
his plant. When the operator checked his answers, he found
sueprested answers that contain a discussion of possible
solutions to the questions posed. Numerous sketches, illus-
trations, photographs, and useful tables were provided to
enhance the appearance of the material and facilitate its
usefulness.
The material is written to allow an operator to study
only selected lessons which apply to his problems, or to
proceed through the entire book, whichever he chooses.
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TABLE I. TREATMENT PLANT OPERATION COURSE OUTLINE
CHAPTER
1
2
3
k
5
6
7
8
9
10
11
12
13
11+
15
16
17
TOPIC
Introduction
Why Treat Wastes?
Wastewater Facilities
Racks, Screens, Comminutors, and Grit Removal
Sedimentation and Flotation
Trickling Filters
Activated Sludge
Sludge Digestion and Handling
Waste Treatment Ponds
Disinfection and Chlorination
Maintenance
Plant Safety and Good Housekeeping
Sampling Receiving Waters
Laboratory Procedures and Chemistry
Basic Mathematics and Treatment Plant Problems
Analysis and Presentation of Data
Records and Report Writing
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TABLE II. TYPICAL TREATMENT PROCESS CHAPTER OUTLINE
SECTION TOPIC
1 Relationship of process to overall plant
2 Purpose and description
3 Plant start-up
Ij. Daily operational problems
5> Sampling and analysis (includes performance
evaluation)
6 Safety
7 Additional useful information
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FIELD TESTING - PHASE I
Initial testing of the material consisted of recruiting
a group of persons willing to test the material and to provide
constructive criticism. The initial group was composed of men
whose experience ranged from over 20 years down to people
interested in becoming operators. Their education level
varied from tenth grade to college graduates.
One week was devoted to each chapter, except two weeks
were allocated to the chapters on activated sludge and labora-
tory procedures because of their complexity and length. Each
participant was requested to work a pre-test, read the
material, answer questions, check his answers, and work a
post-test. While the student did his assignment, he marked
sections that were not clear or difficult to read and he noted
questions whose solutions or answers were not adequately
explained in the chapter. The pre-test was used to indicate
to the student important topics in the chapter and to evaluate
the effectiveness of the teaching techniques and material
presented, when compared with the post-test.
Both the pre and post tests contained essay, multiple
choice, fill-in, matching, and the true-false types of
questions to provide experience in taking various types of
tests. Essay questions were used most because they help
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reinforce knowledge, aid in developing writing skills, provide
the opportunity for the student to indicate what he knows, and
allows the designer of the program to identify weaknesses and
misconceptions in the prepared material or in the participants
experience prior to starting the program.
At each weekly meeting the material was reviewed by the
group on a page by page basis. These meetings were recorded
on tape and areas needing improvement were noted. The writer
of the chapter explained the unclear section to the satisfac-
tion of the participants and these verbal explanations proved
very helpful when the material was revised. Potential
operators were extremely helpful in identifying words used
by professionals that are not understood by the layman. These
words are defined at the beginning of each chapter where they
are used, footnoted in the chapter where they first appear,
and all of these words are listed and defined in one summary
glossary at the urging of the participating operators. A
special pronunciation key using everyday words and syllables
was developed to aid in the understanding of uncommon words.
After each meeting the writer of each chapter rewrote his
material with the aid of the program consultants and education
specialist.
Difficult problems encountered included the sequence of
working the chapters, especially the relationship of mathematics
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and chemistry with respect to the other chapters, the breadth
and depth of the material in each chapter, and the explanation
of theory needed to successfully operate a wastewater treat-
ment plant. Logically one would assume that the operator
must possess a strong background and understanding of the
fundamentals of mathematics and chemistry before he could
comprehend the material in the chapters on the operation of
wastewater treatment processes. Experienced operators coun-
tered that they know little chemistry and were not interested
in mathematics and that they felt their plants were being
operated at a satisfactory level. Efforts by potential opera-
tors revealed that they lacked sufficient familiarity with
treatment plants and vocabulary of the profession to compre-
hend the need and basis for chemistry and mathematics in
treatment plant operation. Discussions with operators
indicated that they wanted to learn the "nuts and bolts" of
plant operation and were not concerned about mathematics or
chemistry.
To solve the problem of the appropriate location of the
chapters on mathematics and chemistry in the work sequence
of the chapters, these chapters were introduced early in the
program but the operator has the choice of working the
chapters, using them for reference, or waiting until the end
to work them. Mathematics are introduced first in Chapter i;
in the operation of grit chambers. The calculations are very
111,
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simple and the mathematical operations gradually become more
difficult with each chapter as the operator works problems
encountered in the daily operation of the various types of
treatment processes. The mathematics chapter was provided
simultaneously with Chapter 1; to serve as a reference and
guide to working mathematical problems in the other chapters.
Chapter 5 °n sedimentation and flotation requires the
use of laboratory procedures to evaluate the performance of
a primary clarifier or sedimentation basin and to determine
whether any adjustments in plant operation are necessary.
The chapter on laboratory procedures and chemistry was pro-
vided with Chapter 5 to serve as a reference and explanation
of laboratory procedures to evaluate the performance of
treatment processes and overall plant performance. Some
experienced operators have completed the chapters on mathe-
matics and laboratory procedures first because they said
they wanted to concentrate on the treatment processes when
they worked on those chapters and not have to refer to other
chapters.
Many operators interviewed before the material was
prepared indicated that in their opinion most of the available
information on the operation of wastewater treatment plants
was too vague, too theoretical, or lacked sufficient instruc-
tions on how to do a particular task. This problem was
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attacked by asking the question, "What does the operator need
to know?" Sketches were provided in the laboratory procedure
chapter to illustrate the measurement of water quality on a
step-by-step basis (11;). Operators were urged to consult
manufactorers' literature for details on maintenance pro-
cedures .
Operators frequently feel that, theory is not pertinent
to the operation of their plant. Basic knowledge required to
operate plants is contained in sections on the principles of
the treatment process and the operation of the process.
Originally this material was placed at the end of each chapter
at the request of the participating operators, but it was
evident that it must be placed at the beginning to provide
the necessary background information to comprehend the
material in the chapter.
Fourteen operators started Phase I and eight were awarded
Certificates of Completion. Most stopped attending before
the third week, stating they agreed to help because they
wanted to see what the program was like. Mainly these were
operators who had attended other operator training courses
in conventional classrooms. They appeared to want to listen
to lectures, but did not wish to spend the time outside of
class going through the material.
16 ,
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Following completion of Phase I and evaluation of the
program, the material was rewritten. With all of the material
available, format was standardized, topics expanded and added
where appropriate, and duplication eliminated.
FIELD TESTING - PHASE II
Phase II consisted of field testing the program with
operators in Northern California and with potential operators
enrolled in the Mechanical-Electrical Technology Program at
Sacramento City College. This group consisted of men and a
woman whose ages ranged from 17 to over 60, experience was
from zero to over 20 years and education varied from grammar
school to a graduate degree (Figure 1).
Chapters 1 through 3 were mailed immediately. When a
chapter was completed by a student, it was mailed to the pro-
gram director who forwarded it to the author of the chapter.
It was corrected, returned to the director for review, and
mailed to the operator with another chapter. Mailings were
arranged to keep the student working as fast as he desired.
Again Chapter l£ on Mathematics was mailed with Chapter [j. on
Racks, Screens, Comminutors, and Grit Removal and Chapter llj.
on Laboratory Procedures was mailed with Chapter 5 on Sedimen-
tation and Flotation.
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75
PHASE II
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After the operator had completed Chapter 3> he was
visited at his plant by the program director and an exper-
ienced operator. The purpose of this visit was to become
acquainted with the operator and his plant, explain the
purpose of the program to him, urge his cooperation in
identifying sections that need improving, and request him
to provide the program director with "tricks of the trade"
that had been omitted from the material.
When the operator was approximately half through the
program he was visited at his plant again. At thio time he
was asked to identify his plant operational problems and
discuss his solutions to insure that solutions to most
typical operational problems were contained in the material.
Occasionally the visitors were able to help the operator
find his problem in the material and also a potential
solution. This approach helped the operator realize that
the material could serve as a valuable reference source when
problems are encountered. Near the end of the program the
operator was visited again to provide the opportunity to
discuss improvements in the material.
One intended purpose of the plant visits was to evaluate
the effectiveness of the material. Originally, a comparison
of the quality of the plant effluent when the operator
started and completed the program was felt to be an appro-
priate measure. At the start of the program the local
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regulatory agency was provided with a list of operators in
the program with the request that inspectors offer to help
the operators with the lessons and to listen for means to
improve the program. The agency responded that all plants
being operated by program participants were meeting discharge
requirements and that the best operators in the region had
enrolled in the program.
At the beginning of the program, supervisors were
notified that their employees had volunteered to participate
in the program. Following completion of the program, super-
visors were polled regarding their impression of the influence
of the program on the operator. All supervisors indicated
that they detected increased communication skills and a
better knowledge of the operation of the treatment plant.
Every agency indicated they would be willing to pay from $10
to $200 per manual for the material for other operators to
participate in the program. None of the operators received
a pay raise upon receipt of his Certificate of Completion.
Performance of operators completing the program on
California Certification Examinations and civil service
examinations is confidential; however, informal discussions
with operators and Certification officials has revealed that
operators who completed the program achieved a much higher
degree of success and higher passing grades than operators
who had not participated in the program.
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Figure 2 illustrates the percentage of operators who
started the program that completed each chapter. Discussions
with a large number of operators, or their supervisors, whc>
stopped working the lessons early in the program indicated
that the operators were not too interested, but their super-
visor- thought it would be a good program and enrolled them
in the program. Chapter 7, Activated Sludge, was an impossible
hurdle for many operators because it was too long and too
difficult and, consequently, was extensively revised. Other
reasons for quitting included passing of the certification
exam and graduation from school. Many operators were unable
to complete the program because of lack of time due to the
demands of a second job. The large number of operators in
remote regions holding second jobs reflects the poor salary
structure in these areas.
In an attempt to reduce the number of persons who did
not complete the program, an illustrator was retained to
improve the presentation of the material (Pig. 3). His
sketches were very pertinent and he has received many compli-
ments on the appropriateness of his work. Revision of
Chapter 7 on Activated Sludge consisted of completely rewrit-
ing the introductory lessons to provide a better insight into
the description of the process, how it works, and what is
required to keep it working. Details on the start-up,
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23
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operation, and maintenance of the process were condensed
where possible.
Again the material was reviewed by the project consult-
ants and educators and rewritten on the basis of the evalua-
tion of the Phase II testing program.
FIELD TESTING - PHASE III
Phase III was a national testing program with operators
from 25 states located all over the United States. These
operators were requested--and many did—to suggest improve-
ments in the lessons where local operational problems had
been overlooked or not included in the material. Vital
statistics of these operators are contained in Figure 1.
Each state and Environmental Protection Agency Regional
Director of Manpower and Training received a copy of the
material and several agencies contributed helpful comments.
Procedures for working the lessons were similar to
Phase II except approximately 20 operators were assigned to
an individual who corrected all of their material. This
plan was instigated to allow the person correcting the
material to become familiar with a group of operators and
encourage them to stick with the program. If an operator
made the same mathematical error in several chapters, he
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could receive comments on how to correct this error. Field
visits, unfortunately, had to be eliminated because of the
dispersed locations of the operators. Contact was maintained
with local operators to encourage suggestions for improvement.
Evaluation of Phase III consisted of comparing the
improvement of scores between the pre and post-tests. Added
to the post-tests in Chapters 9 through 13 and 16 and 17
were reveiw questions. Several of the operators worked the
review questions on the answer sheet they labled pre-test,
confirming a suspicion that they worked the chapter and then
answered both the pre and post-tests. Figure [j. summarizes
the grades received on the post-tests by the operators
completing the program. The results reveal a high degree of
success by these operators on the questions the authors
deemed pertinent to the operation of wastewater treatment
plants. An advocate (19) of programmed instruction claims
that everyone should obtain an A grade because the operator
is not supposed to continue until he understands the material
in each short section.
Following the completion of Phase III the material was
reviewed by consultants and educators and revised where
necessary on the basis of the evaluation of this phase. All
of the material was edited and all words were checked for
reading-skill level (1|). Colloquialisms were eliminated to
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to
fn
O
4^
ctf
O,
O
10 --
I
80 85 90 95
Percent Correct
Out of 1233 Possible Multiple Choice Answers
100
Pig. 1|. Summary of Average Score of Successful Operators on
All Post-Tests, Phase III
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facilitate translation to other languages. Virtually all of
the words remaining in the completed Manual, Operation of
Wastewater Treatment Plants (8), are twelfth-year level or
lower, with the exception of those -words essentdal for the
operator to communicate with his colleagues in the wastewater
treatment profession.
SUMMARY AND CONCLUSIONS
Procedures followed in the development and use of
operator educational material are outlined in this paper. In
summary, the procedure involved:
1. Defining educational objectives
2. Identifying knowledge and procedures essential
to achieve objectives
3. Reviewing educational techniques, materials,
and media
[4.. Developing curriculum
5. Selecting qualified instructors and/or writers
6. Administering the program
7. Evaluating the program
8. Repeating administration and evaluation until
material and method of presentation were
satisfactory
9. Providing procedures to revise'program when
necessary
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A field study manual on the operation of wastewater
treatment plants was developed and tested by experienced
operators which is capable of providing operators with the
information they need to know to operate their plants and
solve operational problems. Operators studying alone or
enrolled in regular courses who use this manual are provided
helpful learning material and a useful reference.
a
KNOW LEDGE ME NTS
This project was funded by the Environmental Protection
Agency, Office of Water Programs, under Technical Training
Grant No. £TT1-WP-16-03.
The authors wish to express their gratitude i^o the many
operators who participated in the development of this program.
Special thanks are due to the men who wrote the chapters and *> ,
our technical and educational consultants. Illustrations in
the manual were drawn by Martin Garrity. F. J. Ludzack,
Chemist, National Training Center, Office of Water Programs,
Environmental Protection Agency, provided many helpful
suggestions throughout the entire developmental period.
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REFERENCES
1. Austin, John H., "Current University Activities in
Wastewater Treatment Plant Operator Training,"
Proceedings Educational Systems for Operators of
Water Pollution Control Facilities, USDI/FWPCA
and Clemaon University, Atlanta, Georgia, Nov. 3-5>»
1969, p. 133-11*9.
2. "Basic Mathematical Computations for the Sanitarian,"
CDC Training Program, Homestudy Course Series,
U.S. Department HEW, PHS, Bureau of Disease Preven-
tion and Environmental Control, Atlanta, Georgia,
19-68, 37 PP.
3. Bloodgood, Don E., Sewage Treatment Practice, Scranton
Publishing Company, Inc., Chicago, 79 pp.
U. Dale, Edgar, Graded Word Lists, Ohio State University,
1970.
5. ERM, published by Educational Research and Methods
Division, American Society for Engineering Education,
published quarterly in October, December, March, and
June.
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6. Erdos, Renee P., Teaching by Correspondence--A UNESCO
Source Book, Longmans, Green & Co. Limited, London,
1967, 218 pp.
7. Jeter, Harold, Audio Visual Scripts for Laboratory
Analysis, EPA/OWP, National Training Center,
Cincinnati, 1970.
8. Kerri, Kenneth D. and Bill Dendy, Operation of Wastewater
Treatment Plants--A Field Study Educational Program,
Environmental Protection Agency, Office of Water
Programs, distributed by Sacramento State College,
Sacramento, California, 1971, l^Oij. pp.
9. Manual of Instruction for Sewage Treatment Plant
Operators, New York Health Education Service, Albany,
New York, 2i|7 pp.
10. Manual of Wastewater Operations, Texas Water Utilities
Association, Austin, Texas, 1971, 755 PP-
11. Manuals of Practice, Water Pollution Control Federation,
Washington, D.C.
12. McCullough, Celeste and Loche Van Atta, Statistical
Concepts, A Program for Self-instruction, McGraw-Hill,
New York, 1963, 3&7 PP»
30
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13. Nagano, Joe, Film on Laboratory Procedures, presented to
the Operators' Short School, CWPCA, Anaheim,
California, May 7, 1969.
ll|. Nagano, Joe, Laboratory Procedures for Operators of Water
Pollution Control Plants, California Water Pollution
Control Association, Anaheim, California, 1969.
15. Programmed Inst r uction Courses, Industrial Training
Service, E.I. DuPont De Nemours & Co. (Inc.),
Wilmington, Delaware.
16. Pursglove, L.A., "Programmed Manuals," Proceedings
Educational Systems for Operators of Water Pollution
Control Facilities, USDI/FWPCA and Clemson University
Atlanta, Georgia, Nov. 3-5, 1969, p. 305-328.
17. Pursglove, L.A. and K.K. Mancy, Elements of Biological
Wastewater Treatment--Overview, Unit 1, Part 1,
University of Michigan, School of Public Health,
Ann Arbor, Michigan, 1968.
18. TEMAC, Programmed Learning Materials, General Science
Series, Encyclopedia Britannica Press.
19. Thompson, Willard M., The Basics of Successful Salesman-
ship; a Self-teaching Programmed Rook. McGraw-Hill,
New York, 1968, 292 pp.
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20. U.S. Department of the Navy, Training Courses in Water
and Sewage Plant Operations, Basic and Intermediate
Courses, Bureau of Yards and Docks, Navdocks P-33U>
Washington, D.C., March I960.
} :-lr:,j'y^ f. '~": :^ V
, __„",, v o ., j. j. J..,«. —.j
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