EPA 660/2-74-071
1974
Environmental Protection Technology Series
Programmed Demonstration for Erosion
and Sediment Control Specialists
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
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RESEARCH REPORTING SERIES
Research reports of the Office of Research anrl Development,
Environmental Protection Agency, have been grouped into five
series. These five broad categories were established to
facilitate further development and application of environmental
technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface
in related fields. The five series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed
to develop and demonstrate instrumentation, equipment and
methodology to repair or prevent environmental degradation
from point and non-point sources of pollution. This work
provides the new or improved technology required for the
control and treatment of pollution sources to meet environmental
quality standards.
This report has been reviewed by the Office of Research and
Development. Approval does not signify that the contents
necessarily reflect the views and policies of the Environmental
Protection Agency, nor does mention of trade names or commercial
products constitute endorsement or recommendation for use.
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EPA-660/2-74-071
February 1974
PROGRAMMED DEMONSTRATION FOR EROSION
AND SEDIMENT CONTROL SPECIALISTS
By
Water Resources Administration
State of Maryland
Annapolis, Maryland
and
Thomas R. Mills
Michael A. Nawrocki
Gregg R. Squire
Homer T. Hopkins
Michael L. Clar
Project No. S800854 (15030 FMZ)
Program Element 1B2042
Roap/Task PEMP 03
Project Officer
John J . Mulhern
Pollution Control Analysis Branch
Office of Research and Development
Washington, D. C. 20460
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U. S. ENVIRONMENTAL PROTECTION AGENCY
Washington, D. C. 20460
For sale by the Superintendent of Documents, U.S. Government Printing Office
Washington, D.C. 20402 - Price $2.15
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ABSTRACT
This project consisted of the development of a series of technical presenta-
tions and a certification plan for erosion and sediment control specialists
and the demonstration and evaluation of two alternative approaches for pre-
senting information on topics relating to erosion and sediment control.
Fifteen technical presentations were prepared. They consisted of a script,
visual aids, and a student handout. Six of these presentations were con-
verted to audiovisual presentations for comparison with the conventional
technical presentations. Each audiovisual presentation consisted of one or
more cassettes containing a narration on a magnetic tape and a synchronized
film strip, a workbook, and an instructor's manual.
This report, as well as accompanying copies of the presentations, under
separate cover, was submitted in fulfillment of Grant No. S800854 (15030FMZ)
by the Water Resources Administration, State of Maryland, under the partial
sponsorship of the U. S. Environmental Protection Agency .
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CONTENTS
Section Page
I CONCLUSIONS 1
II RECOMMENDATIONS 3
III INTRODUCTION 6
IV DEVELOPMENT OF PRESENTATIONS 8
V PROGRAM DEMONSTRATION AND 23
EVALUATION
VI CERTIFICATION PLAN 34
VII REFERENCES 38
VIII APPENDICES 39
in
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ACKNOWLEDGMENTS
This final report for the "Programmed Demonstration for Erosion and Sediment
Control Specialists" was prepared under joint sponsorship of the U.S.
Environmental Protection Agency and the Water Resources Administration,
State of Maryland, by Hittman Associates, Inc. of Columbia, Maryland.
Sincere thanks are extended to Donald J. O'Bryan, Acting Chief, Mining
and Land Modification Branch, EPA, and John J . Mulhern, Project Officer,
EPA, for their support and guidance throughout the demonstration program,.
Special thanks goes to members of the Water Resources Administration,
State of Maryland, especially Marshall T. Augustine, Roger A. Kanerva,
Roy E. Benner, and Albert E. Sanderson, for their technical guidance and
editorial help. Additional gratitude is extended to Roger A. Kanerva and
Roy E. Benner for their assistance in writing presentations.
The contributions provided to this program by the use of 35 millimeter
photographic slides from the U.S. Department of Agriculture, the Maryland
Water Resources Administration, Mr. Marshall T. Augustine, the Maryland
State Roads Commission, the Soil Conservation Service, the soil and water
conservation districts of Howard, Montgomery, and Prince Georges counties
in Maryland, the Baltimore Public Works Commission, and Rummel, Klepper,
and Kahl, Consulting Engineers in Baltimore are also acknowledged with
sincere thanks.
IV
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SECTION I
CONCLUSIONS
1. Sediment & erosion control specialists who participated in the
audiovisual presentations scored higher on a test than a similar
group of persons who viewed the same presentations in a conven-
tional, lecturer type format.
2. From statistical analyses, it can be concluded that the audiovisual
presentations were certainly as effective as the conventional presen-
tations .
3. Participants preferred the audiovisual approach over the conven-
tional approach.
4. The six audiovisual presentations comprise a coherent, abbre-
viated program that can be effectively utilized at the present time
and later integrated into an expanded audiovisual program.
5. The 15 conventional presentations provide a comprehensive ex-
posure to all of the major aspects of erosion and sediment control.
6. The State of Maryland should adopt a certification program re-
quiring contractors engaged in grading activities to have an on-
site certified specialist in charge of the implementation of the
sediment control plans.
7. Only construction sites requiring a "standard" sediment control plan
and those not requiring a plan should be excluded from the certi-
cation requirement.
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8. An interim certification should be issued in Maryland with
experience being the only qualifying criteria.
9. A full certification should be required within two years of the
adoption of a certification requirement. Experience, plus the
passing of a written or oral exam, should be the primary qual-
ifying requirements.
10. The presentation materials developed in this demonstration will
constitute an effective program for qualifying construction per-
sonnel and other persons to pass the certification exam.
11. The Department of Natural Resources, State of Maryland should
administer the certification program under a board appointed by
the Secretary of the Department of Natural Resources.
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SECTION II
RECOMMENDATIONS
Combine the presentations on "Climatology, Hydrology and Hydraulics" and
"Rainfall-Runoff Relationships" into one presentation entitled "Hydrology"
and convert it into the audiovisual format.
Convert the following existing presentations into the audiovisual format:
Presentation No. 2 - Soils
Presentation No. 6 - Plant Materials
Presentation No. 9 - Erosion and Sediment Control Planning
Presentation No. 11 - Wooded Site Development
Presentation No. 12 - Temporary Soil Stabilization
Presentation No. 13 - Prevention of Waterway Erosion
Do not convert Presentation No. 14 "Sediment Control Laws and Regulations
for the State of Maryland," into the audiovisual format.
Write a general presentation on "Stormwater Management" and a presentation
on the "Universal Soil Loss Equation" and convert them into the audiovisual
format.
Prepare an audiovisual presentation on "Vegetative Soil Stabilization" for
each of the major plant growing regions in the country.
The conventional presentations should be given in the following order:
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(1) Presentation No. 1 - Goal, Objectives and Principles of
Erosion and Sediment Control
(2) Presentation No.. 2 - Soils
(3) Presentation No. 3 - Climatology, Hydrology and
Hydraulics
(4) Presentation No. 4 - Rainfall-Runoff Relationships
(5) Presentation No. 5 - Erosion and Sedimentation
(6) Presentation No. 6- Plant Materials
(7) Presentation No. 8 - Control of Runoff During
Construction
(8) Presentation No. 10- Vegetative Soil Stabilization
(9) Presentation No. 13- Prevention of Waterway Erosion
(10) Presentation No. 12 - Temporary Soil Stabilization
(11) Presentation No. 7- Control of Sediment Generated
on Construction Sites
(12) Presentation No. 9- Erosion and Sediment Control
Planning
(13) Presentation No. 11- Wooded Site Development
(14) Presentation No. 14 - Sediment Control Laws and
Regulations for The State of
Maryland
(15) Presentation No. 15- Foreman-Inspector Responsibilities
The audiovisual presentations should be given in the following
order:
(1) Goal, Objectives and Principles of Erosion and Sediment Control.
(2) Erosion and Sedimentation
(3) Control of Runoff During Construction
(4) Vegetative Soil Stabilization
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(5) Control of Sediment Generated on Construction Sites
(6) Foreman-Inspector Responsibilities
Adopt a certification program for erosion and sediment control specialists
in the State of Maryland.
Exclude government inspectors from requiring a certification to perform
erosion and sediment control inspections.
Issue interim certifications based on experience for two years prior to
requiring a full certification, which would involve the passing of an exam.
Administer the certification program in the Department of Natural Resources,
State of Maryland, utilizing a professional board appointed by the Secretary of
the Department.
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SECTION III
INTRODUCTION
This project, the "Programmed Demonstration for Erosion and Sediment
Control Specialists," was performed under an Environmental Protection
Agency demonstration grant to the Water Resources Administration, State
of Maryland. Hittman Associates, Inc., of Columbia, Maryland, was the
prime contractor for the project.
The purpose of the project was to develop a series of presentations on
sediment and erosion control and a certification plan for erosion and sediment
control specialists, utilizing technology developed on EPA Grant No. 15030FMZ,
and to demonstrate its workability. This primarily involved the development
of 15 presentations on various topics relating to erosion and sediment control,
the conversion of 6 of these presentations into the audiovisual format, the dem-
onstration of the program, and the evaluation of ttie audiovisual approach
against the conventional technical presentations with slides.
In developing the demonstration program, full use was made of the infor-
mation gathered on the "Joint Construction Sediment Control Project", EPA
Grant No. 15030 FMZ, conducted for the State of Maryland by Hittman
Associates. The field demonstration program funded under that project
was continued in this project for the purpose of acquiring demonstration
materials for use in developing the slide and audiovisual programs.
Although the demonstration program was developed for the State of Maryland,
it was anticipated that there would be a nation-wide need for such a program.
Accordingly, it leans heavily towards general philosophy and universally
applicable principles and practices. Only two presentations, "Vegetative Soil
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Stabilization" and "Sediment Control Laws and Regulations for the State of
Maryland", are directed primarily towards Maryland and other states with
physiographic similarities or similar institutional arrangements.
Due to space limitations, the presentation materials were not included in
this report. Instead, copies of all materials were delivered under separate
cover to the project officer. Samples are included, however, in the Appen
dices.
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SECTION IV
DEVELOPMENT OF PRESENTATIONS
GENERAL
The primary effort of this program was the development of 15 conventional
presentations , complete with visual aids and student handouts, and six
audiovisual programs consisting of film scripts, written scripts, work
books, and instructor's manuals.
This work involved the taking and collection of over 4,000 separate 35
millimeter color and black and white photographic slides, the contributions
of several writers, both from Hittman Associates and the Maryland Water
Resources Administration, and very close coordination between both parties
and the audiovisual subcontractor for technical review of program material.
CONVENTIONAL PRESENTATIONS
The topics for 15 conventional presentations (see Appendix "A" for presen-
tation sample) were selected so as to provide an integrated program, rather
than a series of presentations on random topics relating to erosion and sed-
iment control. However, each presentation was written so that it would
entirely, or in large part, stand by itself. In setting up the program the
presentations were grouped under three categories - Basic, Specialized,
and General. The breakdown is as follows:
1. Basic Presentations
Presentation No. 1 - Goal, Objectives and Principles
of Erosion and Sediment Control
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Presentation No. 2 - Soils
Presentation No. 3 - Climatology, Hydrology and
Hydraulics
Presentation No. 4- Rainfall-Runoff Relationships
Presentation No. 5 - Erosion and Sedimentation
Presentation No. 6 - Plant Materials
2. Specific Presentations
Presentation No. 7 - Control of Sediment Generated
on Construction Sites
Presentation No. 8 - Control of Runoff During
Construction
Presentation No. 10 - Vegetative Soil Stabilization
Presentation No. 12 - Temporary Soil Stabilization
Presentation No. 13- Prevention of Waterway Erosion
3. General Presentations
Presentation No. 9 - Erosion and Sediment
Control Planning
Presentation No. 11 - Wooded Site Development
Presentation No. 14 - Sediment Control Laws and
Regulations for the State of
Maryland
Presentation No. 15 - Foreman-Inspector Responsibilities
The "Basic" category treats the introductory and background aspects of
erosion and sediment control and provides the participant with the basic
knowledge to more fully comprehend the "Specialized presentations. The
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"Specialized" category covers the actual techniques for controlling erosion
and sedimentation. The "General" category is intended to provide the par-
ticipant with the general knowledge required to implement the total program
of erosion and sediment control and to make him aware of his importance and
function within the control framework.
In addition to the writing of the presentation material, erosion and sediment
control products and practices were demonstrated in Columbia, Maryland
for the purpose of obtaining photographs for use as visual aids.
The desired method of operation in preparing the conventional presentations
was to write the script, complete with recommended visual aids, have it
reviewed by the Maryland Water Resources Administration, and then to
collect the visual aids and write the student handout, (see Appendix "B"
for a sample student handout) To speed progress, photography was often
performed concurrently with the writing of the script. Unfortunately, this
method of operation was not possible for all of the presentations, in that the
writing was performed during the winter months when pertinent construc-
tion activity had stopped. This necessitated the taking of numerous pictures
during the preceding summer and fall in anticipation of requirements for the
winter. In that it was impossible to fully anticipate the requirements, it
became a particularly difficult task to obtain many of the slides. Solving the
problem required the gathering of slides from outside collections, the use of
captions and artwork, staging, and, in the more difficult situations, rework-
ing the script to accommodate the available slides.
Experience showed that it is very difficult to gather pictures of good practices
in an emerging field such as erosion and sediment control. The opportuni-
ties to gather slides to prepare a "horror story" type of presentation were
abundant, but the same was not true of gathering visuals to prepare the "how
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to do it" type of presentations developed in this demonstration. To obtain
the proper visuals, considerable field searching was required, as well as
costly staging operations and artwork.
The length of the presentations varied depending upon how much informa-
tion had to be presented. The lecture time varied from approximately 30
minutes for Presentation no. 1 up to about 75 minutes for Presentation No. 10.
The number of slides used in the presentations ranged between 47 and 104.
In all, over 1,100 slides were used in the 15 conventional presentations.
Final Product
As noted earlier, the materials for each conventional presentation consisted
of a narrator's script, visual aids, and a participant's handout (see Appen-
dices) . Each script contains a content outline and the complete narration
of the presentation (see Appendix "A" for a sample script) . To provide for
the synchronization of the visual aids with the narration, reference was
made to the required visual in the script. The visual references were
numbered consecutively and a brief description of the subject matter was
provided.
All visual aids consisted of 35 millimeter color or black and white slides
(see Appendix "A" for sample of visuals) . The slides for each presentation
were packaged in clear plastic storage sheets, each accommodating 20 slides.
The slide sheets, scripts, and other presentation material were assembled in
standard three ring notebooks. Each slide was marked in the upper right
hand corner with the presentation number and the sequence number. The use
of the number 8-3, for example, refers to Presentation No. 8 and the third
slide to be shown.
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The participant's handouts contain the important information covered in the
narrator's script, grouped under topical headlines (see Appendix "B" for
a sample handout).
AUDIOVISUAL PRESENTATIONS
The six audiovisual presentations were prepared by Educational Communi-
cations, Incorporated of Wayne, Pennsylvania with technical assistance from
Hittman Associates and the Maryland Water Resources Administration. Edu-
cational Communications' work was performed under contract with Hittman
Associates.
The six conventional presentations converted into audiovisual presentations
are as follows:
Presentation No. 1 - Goal, Objectives and Principles of
Erosion and Sediment Control
Presentation No. 5 - Erosion and Sedimentation
Presentation No. 7- Control of Sediment Generated
on Construction Sites
Presentation'No. ,8 - Control of Runoff During
Construction
Presentation No. 10 - Vegetative Soil Stabilization
Presentation No. 15 - Foreman-Inspector Responsibilities
Two criteria were used in selecting the presentations for conversion into
the audiovisual format. First, the presentations were chosen so as to make
up a coherent, abbreviated package that could be used immediately,'and,
then later be integrated into an expanded program, including nearly all of
the remaining presentations not yet converted into the audiovisual format,
and any other presentations that may be developed. The second selection
criteria was that all three of the presentation categories be represented
Presentations No. 1 and No. 5 came from the "Basic" presentation category,
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Presentations No. 7, No. 8, and No. 10 from the "Specific" category, and
Presentation No. 15 from the "General" category.
The first steps in the development of the audiovisual presentations were to
define the target population, general performance objectives, and terminal
behavior, and to select the audiovisual hardware.
Characteristics of Target Population
It was decided by The Water Resources Administration , State of
Maryland , that the presentations would be made available to private contractors
and governmental pollution control agencies. The target population within
these two sectors was defined as construction foreman and inspectors. It
was assumed that the personnel within these categories would have completed
a high school education. It was further assumed that the construction foreman
were well versed in practical procedures for translating engineering designs
into structures on the construction site. The governmental inspectors, on
the other hand, were assumed to have had less construction experience and
the inability, in most cases, to translate engineering designs.
General Performance Objectives
A foreman who studied the audiovisual presentations was expected to acquire
the following abilities:
1. To be able to look at a plan and visualize it
functionally on the site.
2. To be able to schedule the work so measures to
prevent runoff are coordinated with other con-
struction.
3. To recognize various control structures on the plan
and transfer these to the site.
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H. To understand his role and responsibilities
and his relationship with government inspectors.
5. To determine whether the proposed plan will
perform adequately on the site and be able to
go back to the designer with recommendations
for changes if needed.
A government inspector taking this program was expected to develop
the following abilities:
1. To understand his role and responsibilities.
2. To understand the cross relationship between
himself and the contractors' foreman.
3. To determine if the construction site is in com^
pliance with the plan and if it will effectively
control runoff.
4. To be able to report on the reasons for problems and
make proposals for their correction.
5. To be able to make a decision as to what recommenda-
tions he can make and what changes must go back for
re-design and approval.
6. To be able to prepare effective reports concerning
each particular situation.
Terminal Behavior
The terminal behavior determined at the outset of the development of the
presentations Was twofold:
1. At tHfe conclusion of each of the audiovisual
programs, trainees will be required to com^
plete a written test. These tests will incor-
porate various forms of questions relating
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directly to the subject matter just covered.
It will be expected that 90 percent of the
participants will score a correct response
on 90 percent of the questions.
2. As a more long term requirement of this
project, it is expected that participants will
gain increased motivation to perform their
assigned tasks efficiently and cooperate with
all those charged with the responsibility of
reducing erosion damage.
Audiovisual Hardware
It was decided that the audiovisual equipment should have the following
characteristics:
1. Be able to present filmstrips which are
automatically synchronized to the sound.
2. Have the sound tape and filmstrip enclosed
in one integral cassette.
3. Have the capability of being used as a front
screen projector which could be viewed by
groups of approximately 15 persons.
H. Be capable of conversion to a rear screen
projector for individual viewing.
5. Be small and compact enough for an individual
to take home.
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Several brands of audiovisual equipment were evaluated by Hittman Assoc-
iates and the Maryland Water Resources Administration. The audiovisual
projectors manufactured by Audi scan Incorporated in Bellevue, Washington
were selected for use in the program {see Figure 1) .
Figure 1. Audiovisual machine used in the demonstration.
Adjacent screen can be attached for individual
or small group use.
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Program Development
Hittman Associates provided the audiovisual subcontractor. Educational
Communications, Incorporated, with conventional presentations from which to
develop the audiovisual scripts (see Appendix "C" for a sample audiovisual
script) .
Before writing the script for any presentation, specific performance objectives
were determined. In the presentation entitled "Control of Sediment Generated
on Construction Sites", for example, the participant was expected to be able
to accomplish the following things after viewing the presentation.
1. Explain the basic principles of sediment
traps.
2. Describe and detail the use of graded
vegetated buffer areas.
3. Explain the importance of leaving natural
vegetative buffers.
4. Describe the use of contour stripping.
5. Explain the use and construction of sod
inlet filters.
6. Explain the use and construction of gravel
inlet filters.
7. Describe the use of the sandbag sediment
trap.
8. Explain how the straw bale sediment trap
is used.
9. Detail the use of the straw bale perimeter
barrier.
10. Describe the use of the excavated sediment
trap.
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11. Distinguish between wet and dry sediment
basins and the use of each.
In writing these scripts each unit of information was broken into segments
not exceeding approximately 30 words. This formed the descriptive narra-
tion for the presentation. Each narration segment was accompanied by the
description of a visual or a "frame". These visuals were specified as either
photographs, artist sketches, or title boards.
The format used for all presentations consisted of first introducing the theme,
then presenting a unit of information. The information unit was then followed
by a break during which participants were asked to respond to questions in
the workbook (see Appendix "D" for a sample workbook). After all units of
information had been covered, a summary of the material was presented as
a review.
Each presentation had a specific theme. For example, the presentation on
"Vegetative Soil Stabilization" featured Augie the Worm; "Foreman-Inspector
Responsibilities" featured Sherlock Holmes and Doctor Watson as a team of
great men, and "Control of Sediment Generated on Construction Sites"
featured pre-historic villagers.
As each script was completed it was subject to a word by word critical re-
view by representatives of Hittman Associates and of the Maryland Water
Resources Administration. Changes were made to increase clarity and
correct any possible misconceptions.
Suitable photographs to illustrate the concepts described in each visual
frame were selected, where possible, from the extensive library developed by
Hittman Associates. In a number of cases new on-site photographs had to be
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taken to illustrate specific concepts and in the script "Foreman-Inspector
Responsibilities" role play situations were photographed.
Where it was not possible to obtain suitable photographs, Educational Com-
munications had their artist produce color illustrations. This art work was
also fully reviewed by the reviewing committee composed of personnel from
Hittman Associates and the State of Maryland. Upon approval, it was photo-
graphed on 35 millimeter slides.
When all photographs of artwork and field photographs were selected, they
were arranged in sequence and projected for the review committee. The
committee not only ruled on the suitability but also suggested appropriate
cropping where needed. All slides were then copied onto a master filmstrip.
The written narration for the various presentations was read by several
different narrators. Suitable music was mixed into the presentations where
needed. When the recorded sound track had been approved, the tapes were
impulsed with inaudible signals to change the visuals and to stop the presen-
tation when participants were to go to the workbooks.
Final Product
Each audiovisual presentation was packaged in plastic cassettes containing
both a magnetic tape sound track and a synchronized 16 millimeter film
strip (see Figure 2) .
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Figure 2. Cassettes containing a magnetic
tape sound track and film strip,
and an audiovisual machine, with
inserted cassette, ready to operate
Each cassette has a running time of approximately 15 to 20 minutes. Two of
the presentations required only one cassette to present the information, two
others required two cassettes, and the remaining two required three.
It is estimated that the total time required to present each cassette is about
30 minutes. This provides for workbook exercises and discussions.
Workbooks were also prepared for the audiovisual presentations (see
Appendix "D" for a sample workbook). These were designed to serve as an
additional reinforcement and as a reference document that the participant
can retain. In addition to containing questions to be answered at each
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workbook stop during the program presentation, the workbooks contain a
review test, and a descriptive outline of the subject matter.
To assist the supervisor in giving the programs a manual was prepared
for each program (see Appendix "E" for a sample manual) . These documents
contain information on how to set up the program and operate the audio-
visual machines, list the primary objectives of the program, provide a list-
ing of suggested discussion topics, and contain the answers for all of the
questions in the participant's workbook.
Audience
The audiovisual programs were designed primarily for use by participants
in small groups of up to 15 people with a knowledgable supervisor in atten-
dance. It was also anticipated that on occasions an individual would be asked
to study the programs by themselves.
The equipment selected for use in the demonstration has the capability of
being connected to a standard 35 millimeter, carrousel type projector for
use by large audiences. The sound track can still be used, but instead
of the standard 16 millimeter film strip, 35 millimeter slides are used for
visuals (see Figure 3) .
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Figure 3. Audiovisual machine connected to
a carrousel type projector for show-
ing to a large audience.
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SECTION V
PROGRAM DEMONSTRATION AND EVALUATION
GENERAL
As part of the program, a demonstration was conducted to evaluate the con-
ventional presentation approach versus the audiovisual approach. As vis-
ualized, the conventional approach would be a scientist or engineer with
little or no public speaking experience who narrates a slide show and passes
out student handouts. It is thought that in nearly all cases, the narration
would be read verbatum from the script. It was further assumed that during
the question and answer period, which follows each presentation, some
additional information, not found in the script, may be interjected.
The audiovisual approach was assumed to involve the use of an audiovisual
machine and workbook in the presence of a supervisor. His primary func-
tion would be to lead group discussions and answer questions. The ideal
audience for this approach consists of no more than 15 persons. However,
as noted earlier in the report, the program can be adapted to larger aud-
iences by using 35 millimeter slides rather than the standard 16 millimeter
film strip.
DEMONSTRATION
The demonstration and evaluation was conducted on a typical target aud-
ience consisting of inspectors and construction foremen.
Due to the coincidence of the demonstration and evaluation program with
the active construction season, it was not possible to obtain enough time to
demonstrate all of the presentations and evaluate all six audiovisual programs
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against their conventional counterparts. Instead, it was decided to use
only two presentations to compare the different approaches. These were
the presentations on "Coal, Objectives and Principles of Erosion and Sediment
Control" and on "Erosion and Sedimentation". A third presentation, entitled
"Control of Runoff During Construction", was demonstrated to gather com-
ments from the audience regarding preferences for the two approaches.
PROCEDURE
Government inspectors and contractor's foremen were invited to participate
in the demonstration and evaluation program. The program was held at
Hittman Associates in Columbia, Maryland on June 13, 1973. A total of
26 men arrived.
As each man arrived he was given a form, prepared by the Water Resources
Administration, on which he could record profile information (see Appendix
"F"). Each form was numbered consecutively from one through twenty-six.
Following an'introduction and statement of the purpose of the project, the
men with odd numbered forms were asked to leave the room and go to another
location where they were shown the audiovisual program. Those with even
numbered forms were asked to stay in the first room and were then given a
conventional presentation.
During the first period, both groups viewed the presentation on "Coal,
Objectives and Principles of Erosion and Sediment Control". The group
with odd numbers received the information via an audiovisual program and
the group with even numbers received it via a conventional slide-illustrated
presentation. In the second period the groups viewed the material on "Erosion
and Sedimentation". Again, the odd numbered group, received the audio-
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visual version and the even numbered group received the conventional
presentation.
Both groups were then given the same evaluation test (see Appendix "G") .
This was a test containing 47 questions. Multiple choice, true or false, and
completion of sentences were the test forms used. The possible score was 69.
Following the test, both groups had lunch and then they reversed their roles.
That is, the odd numbered group received a conventional presentation and
the even numbered group received an audiovisual program. They both were
exposed to the same subject, namely "Control of Runoff During Construction."
Both groups were then given a form on which to evaluate the two different
methods of presentation (see Appendix "H") .
TEST RESULTS
The odd numbered group of 13 received the audiovisual presentation and
the even numbered group of 13 received the lecture. Thus, the odd num-
bered group was the experimental and the even numbered group was the
control.
Table 1 shows the raw number of errors scored by each individual. The
percentage of correct answers has also been calculated.
TABLE 1. EVALUATION TEST SCORES
Experimental (Audiovisual)
Subject Test Errors Percent Correct
1 23 66
3 5 93
5 8 88
7 5 93
9 3 96
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11 8 88
13 5 93
15 6 91
17 9 72
19 2 97
21 11 84
23 8 88
25 6 91
TOTAL= 1140
Total Errors = 99
Mean Errors = 7.7
Mean Percent correct
answers =
CONTROL (Conventional)
Subject Test Errors Percent Correct
29 72
4 11 84
6 17 75
8 2 97
10 12 82
12 9 72
14 6 91
16 5 93
18 4 94
20 18 74
22 4 94
24 21 69
26 18 74
TOTAL = 1071
Total Errors = 136
Mean Errors =10.5
Mean percent correct
answers = 82%
26
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PROFILE OF PARTICIPANTS
Table 2 shows two of the key characteristics taken from the profile forms
completed by the participants. It has been completed to show if a specific
participant was an inspector (an X opposite the participant number) and
whether he had completed at least two years of college (an X opposite the
participant number in the column headed College) . Participants without an
X were construction foremen or had not completed two years of college. All
participants had graduated from high school.
TABLE 2. PROFILE OF PARTICIPANTS
Experimental (Audiovisual)
Subject Inspector College
1 X
3 X
5
7 X
9 X
11 XX
13 X
15
17
19 X
21 X
23 X X
25 x
27
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CONTROL (Conventional)
College
X
X
X
X
Subject Inspector
2 X
4 X
6
8 X
10 X
12 X
14
16 X
18
20
22 X
24 X
26
PREFERENCE OF PARTICIPANTS
Table 3 shows the subjects in each group who indicated a general preference
for the audiovisual presentation. Those not marked with an X indicated a
preference for the conventional presentation.
TABLE 3. ATTITUDE TOWARDS METHOD OF PRESENTATION
Experimental
Subject
1
3
5
7
9
11
13
15
17
19
21
23
25
Favorable to A/V
X
X
X
X
X
X
X
X
X
X
X
Subject
2
4
6
8
10
12
14
16
18
20
22
24
26
Control
Favorable to A/V
X
X
X
X
X
X
X
Total = 11
Total = 8
28
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STATISTICAL ANALYSES
Since the test population was rather small (thirteen in each of two groups)
and only two conditions existed (an experimental group E instructed by
means of audiovisual programs and a control group C instructed by means
of a lecture), the applicable statistical techniques are the Mann-Whitney U
test and the Kolmogarov-Smirnov two-sample test.
Null Hypothesis
H : There is no difference in the number of errors
o
made in answering the evaluation questions giv-
en the two groups.
Alternative Hypothesis
H : The experimental group E will score fewer errors
in answering the evaluation questions than will
the control group C.
Kolmogarov-Smirnow Two-Sample Test
Test Scores (Percentage)
95-100 90-95 85-90 80-85 75-80 70-75 65-70
S13 (X)~E 2/13 7/13 10/13 11/13 11/13 12/13 13/13
S (X)-C 1/13 5/13 5/13 7/13 8/13 12/13 13/13
2
S13/X)
-S (X) 1/13 2/13 5/13 4/13 3/13 0 0
2
29
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The table of Critical Values of K shows that for N of 13, K should be 7 or
more at the 0.05 level of probability. Thus a K of 5 is not significant at
a = o.05.
Chi-Square Test
If we extend this with a chi-square approximation:
x = 4D (n1n2/ni+n2^
= 4 (5/13) 2l3x13/13+l3
= 100/169 x 169/26
= .59 x 65
= 3.84
df (degree of freedom) = 2
In the table for Critical Values of chi-square we find that x =3.84 is
significant at 0.2 for 2 degrees of freedom.
The Mann-Whitney U Test
The following breakdown shows the scores arranged in rank order with
the identity of each score indicated as experimental (E) or control (C).
97 97 96 94 94 93 93 93 93 91 91 91 88 88 88 72
EC ECCEE ECEECEE EE
72 72 84 84 82 75 74 74 69 66
CCECCCCCCE
U = 0+2+2+5+7+11+11+12
= 60
30
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The critical value of U for a one-tailed test a - 0.05 and an n and n
of 13 is 51. Thus our results are not significant at the 0.01 level.
31
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DISCUSSION
The experimental group taken as a whole did score better on the test than
did the control group. The experimental group made a total of 99 errors as
compared with a total of 136 errors made by the control group. That was a
mean score of 88 percent for the experimental group and 82 percent for the
control group.
From Table 2 we find that the experimental and control groups were equally
divided with respect to employment and level of education. Both groups had
eight inspectors and both had four individuals who had completed two years
of college. This distribution was fortuitous considering that the group selec-
tion was made on a completely random basis.
Although the experimental group scored better than the control group, the
statistical significance is only marginal. With such a small group of sub-
jects who already have some professional experience in the subject area
of the test, it is not surprising to find that there is not a highly significant
difference between the test scores.
The evaluation of the presentation by the individuals in the two groups does
present some significant information. Of the 13 subjects in the experimen-
tal group, 11 were favorable to the audiovisual presentation while only
eight were favorable in the control group. This might be explained by
the fact that the experimental group had more exposure to the audiovisual
technique and had thus grown more accustomed to it. However, both groups
clearly preferred the audiovisual presentation over the lecture.
Some of the statements expressing preference for the audiovisual program
were:
32
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"I think the audiovisual method of presentation is a
100 percent improvement over the old lecture method.";
"This type of presentation was much more interesting";
"More lively than the average lecture—this is particu-
larly important with technical material"; "Held atten-
tion better"; "Audiovisual program was far easier to
follow"; "This was the most effective method of pre-
senting and demonstrating new material I have ever
seen."
Criticism of the audiovisual approach mainly concerned the large number of
breaks in the program for questions and discussions. This may not have
been made had the programs been presented to individuals in a one to one
situation, with a rear screen in a well lighted room. Part of the problem
with frequent breaks was that changes back and forth from a dark room to
full light had to be made.
In summary, it may be said that the audiovisual presentation was certainly
as effective as a conventional lecture and most individuals preferred it to
the lecture.
33
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SECTION VI
CERTIFICATION PLAN
GENERAL
A requirement of this demonstration program was to develop a plan for the
certification of erosion and sediment control specialists in the State of
Maryland.
The framework for this certification program was developed by Hittman
Associates, working closely with the Maryland Water Resources Administra-
tion.
It was mutually decided that the primary thrust of the plan would be to
certify the on-site erosion and sediment control specialists. The word
"specialist" is intended to mean only construction foreman or supervisors.
The majority of the governmental inspectors are not specialists in that they
are also responsible for the inspection of other construction related functions
and pollution sources. Of course, it is not felt that the erosion and sediment
control inspector should be denied the opportunity to acquire the certification,
only that its acquisition not be considered an essential requirement of his job.
However, it is important that the governmental inspector be exposed to the
program developed in this demonstration. It is felt that state and local
agencies responsible for erosion and sediment control will readily and
voluntarily utilize the program. Strong leadership by the state will be
an important factor in this regard.
On the other hand, it is felt that many of the private construction contractors
performing grading work will not quickly, nor fully utilize the states'
program unless they are legally required to have a certified specialist
34
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in charge of the implementation of erosion and sediment control plans on
their construction sites. This requirement can be accomplished by an
amendment to the existing Maryland Sediment Control Law and/or Regulations.
This amendment would state to the effect that all contractors performing
grading operations shall have an on-site certified erosion and sediment con-
trol specialist to supervise the implementation of the erosion and sediment
control plans. Only those construction sites not requiring a sediment control
plan or requiring a standard plan, as defined in the Maryland Sediment
Control Rules and Regulations, would be exempt from this requirement.
IMPLEMENTATION
One integral part of a program to certify erosion and sediment control
specialists would be the dissemination of the materials developed in this
demonstration to the counties, constructors, and educational institutions
to help personnel to become knowledgable erosion and sediment control
specialists. This can best be accomplished by holding small seminars
with a knowledgable person in charge of the presentations. State and
local governmental agencies, soil and water conservation districts, educa-
tional institutions, and large contractor's would readily utilize the material
for this use. When a group cannot be assembled, the individual viewing
method could be employed. The audiovisual programs are well suited for
this type of information dissemination.
In that it will take some time to certify these specialists, it is felt than an
interim certification should be initially issued and a time limit set for full
certification. It is recommended that an interim certification be required by
July 1, 1974, at which time the amendment to the law and/or regulation
would become effective, and that a full certification be required by July 1,
1976.
35
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Interim Certification
The minimum requirements for interim certification should be three years
grading or related construction experience, one year of which must be in
a supervisory capacity which includes responsibility for the implementation
of erosion and sediment control plans. No test would be required, but an
application would have to be made to the Maryland Department of Natural
Resources and approved by the board and an interim certificate issued to
the applicant.
Full Certification
Full certification would require five years of grading or related construction
experience, two years of which must be in a supervisory capacity which in-
cludes responsibility for implementing erosion and sediment control plans.
Up to two of the three years of non-supervisory experience could be substi-
tuted by job-related, post-high school education.
The applicant would have to apply to the state for the certification and pass
a written or oral test on the subject of erosion and sediment control. The
tests would be geared to the training program developed in this demonstra-
tion and would be administered two or more times a year, depending upon
demand. The applicant would be allowed to take an oral exam if he failed the
written test at least twice and had taken the prescribed state training pro-
gram consisting of the audiovisual presentations. No limit would be set on
the number of times the applicant could take the test.
Organization
The program would be administered by a Maryland Board of Erosion and
Sediment Control Specialist, composed of five to seven representative mem-
bers appointed by the Secretary of the Maryland Department of Natural
36
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Resources. This body would be responsible for promulgating and enforcing
rules and regulations, developing and administering the testing program,
awarding "certificates", and collecting certification fees. Total or partial
funding would come from an application fee charged for the initial certifica-
tion and a renewal fee collected every two years.
The board would have to be assembled no later than January 1, 1974. To
achieve interim certification by July 1, 1974, an application form would be
required prior to January 1, 1974. This could be developed by the Depart-
ment of Water Resources and patterned after the application forms used by
the Maryland State Board of Well Drillers, the Maryland Board of Certifica-
tion for Industrial Wastewater Works Superintendents, and other state profes-
sional boards. The experience of these same boards would also be very
helpful in setting up the administrative structure of the program and in pre-
paring other essential documents.
37
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SECTION VII
REFERENCES
1. Guidelines for Erosion and Sediment Control Planning and
Implementation, Water Resources Administration, State of
Maryland and Hittman Associates, Inc., for EPA, EPA Report
No. EPA-RZ-72-015, August 1972.
2. U.S. Department of Agriculture, Soil Conservation Service,
College Park, Maryland, Standards and Specifications for
Soil Erosion and Sediment Control in Urbanizing Areas, 1969.
38
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SECTION VIII
APPENDICES
Section Page
A. Sample Conventional Presentations and Visuals 40
B. Sample Conventional Presentation Handout 70
C. Sample Audiovisual Script 80
D. Sample Audiovisual Workbook 98
E. Sample Audiovisual Supervisor's Manual 121
F. Participant Profile Form 130
C. Evaluation Questions 133
H. Evaluation of Presentation Form 144
39
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APPENDIX A
SAMPLE CONVENTIONAL PRESENTATION
AND VISUALS
-------
PROGRAMMED DEMONSTRATION
FOR
EROSION AND SEDIMENT
CONTROL SPECIALISTS
PRESENTATION NO. 7
CONTROL OF SEDIMENT
GENERATED ON CONSTRUCTION SITES
Project No. S800854 (15030 FMZ)
-------
ACKNOWLEDGEMENT
Acknowledgement is hereby made that this material was pre-
pared under the assistance of a jointly sponsored Grant program
by the U.S. Environmental Protection Agency and the State of
Maryland.
42
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LESSON NO. 7
CONTENT OUTLINE
I. INTRODUCTION
II. VEGETATIVE PRACTICES
A. Natural Vegetative Buffers
B. Woodland Areas
C. Graded Vegetative Buffers
D. Contour Strips
E. Sod Inlet Filters
III. STRUCTURAL
A. Dikes and Filters
1. Gravel Inlet Filter
2. Interceptor Dike and Inlet. Filter
B. Sediment Traps
1. Sandbag Trap
2. Straw Bale Trap
3. Straw Bale Barrier
4. Excavated Trap
C. Sediment Basin
1. Dry Basin
2. Wet Basin or Pond
3. Maintenance
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The subject of this presentation is "Control of Sediment Generated on
Construction Sites. " By this, we mean the trapping of sediment on the
construction site as near its point of origin as possible. In an indirect
sense, you may think of erosion control practices as doing this, in that
they are designed to reduce soil erosion which, as you are aware, is the
source of sediment. However, a point to keep in mind is that we can only
expect reasonable erosion control. Thus, even with the best plan, some
erosion must be anticipated and, therefore, some sediment will be gen-
erated. This presentation is directed at the control of this sediment.
In an erosion and sediment control plan, we establish two separate
lines of defense against sediment damage. The first defense is the erosion
control which reduces the amount of sediment that will be generated and the
second is the sediment control which prevents much of the sediment from
uncontrollable soil erosion from leaving the construction area. To be fully
effective in preventing costly sediment damage and, at the same time, to
prevent ugly erosion and minimize the loss of precious topsoils, both
defenses must be used.
How do we keep this sediment from damaging the environment? This
is accomplished by using vegetative and structural practices, some very
simple and others more complicated, that trap most of the sediment before
it leaves the construction site. The purpose of this presentation is
to show you some of these practices and to point out pertinent factors
regarding their construction, use, and maintenance.
-------
Sediment control practices are designed to slow the flow of water
either by spreading, ponding, or filtering. By so doing, the ability of the
water to transport sediment is reduced and sediment settles out of suspen-
sion. The amount of sediment removed from the runoff is dependent upon
three factors: First, the speed that the water flows through the trap;
secondly, the length of time the water is detained; and lastly, the size and
weight of the sediment particle carried into the trap.
With regard to the first two factors, the slower the flow of water and
the longer it is detained, the greater will be the quantity of sediment removed
The size and weight of the sediment particles determine the speed at
which they settle out of suspension. The larger and heavier a particle, the
faster it settles out. The efficiency of sediment trapping is expressed as
the percent of sediment removed from the runoff.
Now that we have reviewed the basic principles governing the function
and efficiency of sediment traps, let's look at some of the practices used to
trap sediment.
SLIDE NO. 1 - CAPTION: VEGETATIVE PRACTICES
STRUCTURAL PRACTICES
There are two types of sediment control practices — vegetative and
structural. Let's look at the vegetative practices first.
SLIDE NO. 2 - CAPTION: VEGETATIVE PRACTICES
1. NATURAL VEGETATIVE BUFFERS
2. WOODLAND AREAS
3. GRADED VEGETATIVE BUFFERS
4. CONTOUR STRIPS
5. SOD INLET FILTERS
-------
These include natural vegetative buffers, graded vegetative buffers, contour
strips, woodland areas, and sod inlet filters.
SLIDE NO. 3 - NATURAL VEGETATIVE BUFFER
A natural vegetative buffer is a strip of natural vegetation preserved
along the downhill perimeter of the graded area to slow and filter overland
flow. Keep in mind that this is one of the more effective and economical
methods of removing sediment from overland flow. The preservation of
such a buffer is most essential along waterways.
The need for preserving natural buffer areas must be recognized at
the planning and design stage of development and these areas must be
prominently displayed on the construction plans as off-limits to all construc-
tion activity.
SLIDE NO. 4 - UTILITY CONSTRUCTION ALONG A STREAM
Except for essential roadway crossings, no construction must be
allowed within the buffer area. Good planning by the engineer and careful
grading by the contractor could have preserved a protective buffer along
this stream and prevented serious sediment pollution. Instead, all of the
vegetation was destroyed along the stream bank and the spoil from the
utility excavation was pushed into the stream.
SLIDE NO. 5 - STOCKPILED SOIL ON A FLOODPLAIN ,
This is another example of poor sediment control planning. The
contractor was allowed to stockpile soil on a floodplain. Not only is the
chance of sediment pollution from overland flow greatly increased by this
action, but the prospects of damaging flooding coupled with very severe
erosion is greatly enhanced.
46
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SLIDE NO. 6 - NATURAL VEGETATIVE BUFFER DAMAGED
BY CONSTRUCTION TRAFFIC
This is still another example of what not to do to a vegetated buffer
area whether it be natural or planted. Vegetation damaged by uncontrolled
construction traffic cannot efficiently filter overland flow. Keep all traffic
out of the area and maintain a vigorous cover of vegetation.
SLIDE NO. 7 - VEGETATIVE BUFFER BELOW A FILL
Because of its low, dense growth and other factors, grass is the best
vegetative filter material. Thick, low-growing legumes such as white or
red clover are also effective filters.
Even during the dormant winter months, the mat provided by the dead
foliage still slows the flow of runoff and traps sediment before it reaches
the drainage system.
SLIDE NO. 8 - WOODLAND LITTER
The thick mat of litter covering natural woodland areas also provides
a high degree of filtering action as well as aiding in the absorption of runoff.
SLIDE NO. 9 - SEDIMENT DEPOSITION IN A WOODLAND AREA
Considerable care must be exercised, however, in utilizing woodland
areas for trapping sediment. The deposition of a couple of inches or more
of sediment around a tree may reduce the oxygen supply to the shallow feeder
roots to such an extent that the tree will die. It is best to use such areas
only for the filtering of overland flow and not for filtering concentrated
flow containing heavy concentrations of sediment.
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SLIDE NO. 10 - TREES DESTROYED BY SEDIMENT
Remember, it is a simple matter to reestablish a cover of grass
destroyed by sedimentation, but not so a stand of trees.
SLIDE NO. 11 - CONSTRUCTED VEGETATIVE BUFFER
When it is not possible to preserve a natural vegetative buffer, one
can be constructed. We then refer to it as a constructed vegetative buffer.
Planning for the construction must be done during early design stages.
The flatter and the longer the buffer area can be made, the more
sediment it will retain. A positive grade of two percent will provide con-
trolled spreading and runoff.
SLIDE NO. 12 - CONSTRUCTED VEGETATIVE BUFFER
Timely establishment of vegetation on the buffer is a must if it is to
be fully effective.
SLIDE NO. 13 - SEDIMENT-LADEN RUNOFF FLOWING
OVER A GRASSED AREA
A thick stand^of grass slows the overland flow and filters out sediment.
In addition to filtering the flow, the vegetation allows more water to be
absorbed by the soil and thus decreases the ability of the runoff to transport
sediment.
SLIDE NO. 14 - SEDIMENT TRAPPED BY GRASS BELOW
: A GRADED AREA
Note the effectiveness of both the flattened slope and the grass in
trapping sediment from the overland flow coming off the graded area.
48
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SLIDE NO. 15 - SODDED DRAINAGEWAY ADJACENT TO
A GRADED AREA
Staged grading is a means of providing a vegetative buffer along a
drainageway. In this case, the drainageway was constructed and stabilized
with vegetation prior to the beginning of roadway construction.
SLIDE NO. 16 - GRASSED EMBANKMENT ABOVE A DENUDED
BUFFER STRIP AND CHANNEL CHANGE
This roadway construction site reflects very poor planning on the
part of the engineer. The channel change and buffer strip were constructed
before the embankment in the foreground. The buffer strip was not vegetated
prior to the embankment construction. In fact, the embankment was vege-
tated before the buffer area.
SLIDE NO. 17 - SEDIMENT WASHED INTO WATERWAY
By failing to promptly vegetate the buffer strip, thousands of tons of sediment
were washed into the lower-lying waterway.
SLIDE NO. 18 - SEDIMENT-CLOGGED CHANNEL AND
RESULTING BANK EROSION
The heavy deposition of sediment in the channel forced the stream to
meander and erode the bank. Additional sediment was introduced into the
drainage system as a result.
SLIDE NO. 19 - VEGETATIVE CONTOUR STRIPS OR BUFFERS
-------
Here is a sediment trapping method that has been borrowed from the
farmer. It is used to break the flow of runoff on long hillsides and is called
contour stripping. It involves the establishment of strips of vegetation,
usually grass sod, along the ground contour at regular intervals up the slope.
These buffer strips slow the flow and reduce the amount of runoff, thereby
reducing erosion, while at the same time trapping much of the sediment
generated from unpreventable erosion.
SLIDE NO. 20 - VEGETATIVE "RIGHT-OF-WAY" BUFFER
The use of a vegetative buffer near the base of a highway slope serves
the same function as the contour strips.
SLIDE NO. 21 - SOD INLET FILTER
The sod inlet filter is another vegetative practice used to control
sediment. It consists of pads of sod placed around the storm drain inlet and
works on the same principle as the vegetative buffer areas previously dis-
cussed. The grass slows the flow of water into the inlet and filters out
appreciable amounts of sediment. The size.of the sodded area is varied
depending upon the amount of runoff expected at the inlet. This practice
should only be used to handle light concentrations of sediment. It can best
be used after final grading is complete and during the establishment of a
vegetative cover.
SLIDE NO. 22 - CONCENTRATED RUNOFF CARRYING SEDIMENT
50
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Once the flow becomes concentrated, as it does in ditches and other
drainageways, the trapping of sediment becomes much more difficult and
expensive.
SLIDE NO. 23 - STORM DRAIN CLOGGED WITH SEDIMENT
Although it is not feasible to trap all of the generated sediment, we
can certainly retain enough of it to prevent disastrous damage such as this.
Remember, the amount of sediment that escapes our control practices must
be kept to a level that the waterway can effectively handle.
To prevent this type of damage, structural practices are also required
to control the sediment.
SLIDE NO. 24 - CAPTION: STRUCTURAL PRACTICES
1. DIKES AND FILTERS
2. SEDIMENT TRAPS
3. SEDIMENT BASINS
These include dikes and filters, sediment traps, and sediment basins.
On urban construction sites and on major highway projects where
storm drains are used, the prevention of sediment damage to the drainage
system becomes a particularly important task.
SLIDE NO. 25 - UNPROTECTED STORM DRAIN INLET
To provide for drainage during construction, storm drains must be
installed well ahead of final grading. As a result, sediment generated on the
graded areas is given unrestricted access to the drainage system downstream
of the construction site.
51
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SLIDE NO. 26 - SEDIMENT IN STREAM CHANNEL BELOW
STORM DRAIN OUTFALL
Failure to take adequate measures to trap much of the sediment before
it reaches the storm drainage system will lead to extremely costly damage
to the storm drain as well as to the waterways lying below the outfall.
SLIDE NO. 27 - SEDIMENT CLOGGING STREAM IN
WOODLAND AREA
This is a common example of what happens when sediment is given
unrestricted access to the storm drainage system. The cost to remove
the sediment from this stream will run to several thousands of dollars and,
in many instances, will be borne by the taxpayer. Consider also the damage
to the trees and other vegetation as well as the total destruction of the stream
ecology which cannot be measured in dollars and cents.
SLIDE NO. 28 - GRAVEL INLET FILTER
In this case, coarse gravel was piled around an inlet to form a barrier
that will both temporarily impound runoff and act as a filter. This structure
is commonly referred to as a gravel inlet filter.
Crushed stone is also used to construct this type of filter barrier. In
addition to providing a certain amount of filtering action, gravel or crushed
stone is highly resistant to erosion should overtopping occur during heavy
storms.
SLIDE NO. 29 - GRAVEL INLET FILTER ALONG PROPOSED
ROADWAY GUTTER
52
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The configuration of the gravel inlet filter will depend upon the type of
inlet being protected. This, for example, is a standard inlet used along
concrete roadway gutters in urban areas. In this case, the stone is placed
directly in front of the inlet opening. To keep the stone from falling into
SLIDE NO. 30 - DRAWING OF GRAVEL INLET FILTER
ALONG ROADWAY GUTTER
the storm drain, concrete blocks are inserted in the opening. A board
placed across the opening with a space of at least one-half inch at the top
and bottom will also work.
SLIDE NO. 31 - GRAVEL INLET FILTER PONDING RUNOFF
As mentioned before, an inlet filter is designed to temporarily pond
runoff as well as to act as a filter. Ponding* slows the flow of runoff and
allows much of the sediment to settle out of the water.
SLIDE NO. 32 - GRAVEL INLET FILTER REQUIRING
MAINTENANCE
Prompt maintenance is a very essential requirement for the successful
operation of a sediment trap. As you are aware, in order for this inlet filter
to be fully effective, it must be able to temporarily pond and filter the runoff.
Completely clogged with sediment, it can do neither.
SLIDE NO. 33 - BREACHED INTERCEPTOR DIKE
53
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When clogging occurs, the sediment is simply carried over the stone
and into the storm drain or, as in this case, the interceptor, dike which
directs the water into the inlet was washed out, allowing the sediment and
runoff to continue down-the right-of-way and onto the lower-lying highway.
From there, it quickly found its way into the storm drainage system and
eventually into the natural drainage courses.
To prevent this from happening, the trap must be inspected after eacl
storm and cleaned prior to becoming ineffective — not after. Furthermore,
the sediment that is removed must not be disposed of back on the graded
right-of-way, but instead in a stabilized area away from the grading where
the sediment cannot be reintroduced into the drainage system. A solution
that would allow it to be disposed on the site would be to bury it in a fill.
Care must be exercised, however, to see that an adverse foundation con-
dition is not created.
SLIDE NO. 34 - SOIL INTERCEPTOR DIKE AND GRAVEL
INLET FILTERS
On roadway rights-of-way, an interceptor dike is used to intercept
runoff coming down the graded roadway and divert it into storm drain inlets
protected by gravel filters. By combining the two structures, the trapping
efficiency is greatly increased. As you can see, water is ponded along the
entire length of the interceptor dike.
As well as aiding in the trapping of sediment, the interceptor dike, as
you may recall from a previous lesson, also helps control erosion by diverting
runoff away from the graded surface.
SLIDE NO. 35 - SANDBAG SEDIMENT TRAP
54
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Any structure that interrupts the flow of runoff that is transporting
the sediment will trap sediment. The amount of sediment that it will collect
or its efficiency will depend on how long it is able to detain the flow.
This is a sandbag sediment trap constructed across a ditch upstream
of a storm drain inlet. This practice is a quick and economical method of
temporarily disrupting flow and trapping the coarser sediment particles.
By positioning these barriers at regular intervals along the ditch, a high
degree of trapping efficiency can be achieved.
The sandbags are filled with soil or stone and are stacked in an inter-
locking fashion to provide additional strength for resisting the force of the
flowing water.
SLIDE NO. 36 - CROSS SECTIONAL DRAWING OF TYPICAL
SANDBAG STRUCTURE
A major cause of failure for many of the temporary sediment traps is
piping. This is the flow of water beneath the structure rather than through
or over the top of the barrier. By setting the sandbags in a trench excavated
a minimum of six inches in depth and by firmly tamping soil along the uphill
face of the bags, the chance of piping failure is greatly reduced.
SLIDE NO. 37 - STRAW BALE SEDIMENT TRAP
Straw or hay bales are also used to construct small temporary barriers
to trap sediment. Straw bale traps are a fast and economical means of
providing a temporary sediment trap, Although they function well when
properly installed, straw bak: traps :Jo deteriorate rather rapidly. One
means of prolonging the service ii/e ~-i the trap is by using wire-tied bales
rather than those tied with twine.
55
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When only twine-tied bales are available, the same effect can be achieved
by securely wrapping them with sturdy wire at the location of the twine.
In constructing the trap, the bales are laid on their sides and staked
in place. At least two wooden or metal stakes are driven through each bale
and into the ground.
SLIDE NO. 38 - CROSS SECTIONAL DRAWING OF A
STRAW BALE TRAP
As in the case of sandbag traps, piping beneath the structure can
render the trap ineffective. To prevent this, the straw bales are also set
in a trench excavated to a depth of at least six inches and excavated soil is
compacted along the upstream face.
SLIDE NO. 39 - SEDIMENT COLLECTED BEHIND A
STRAW BALE TRAP
Like all other sediment traps, straw bale and sandbag traps also
require periodic inspection and very prompt maintenance if they are to
continuously function. Again, sediment removal does not mean shoveling
the sediment off to one side where the next storm will send it directly back
into the drainage system. Instead, properly dispose of it in a noncritical
fill or some other safe area.
SLIDE NO. 40 - STRAW BALE PERIMETER BARRIER
Before departing from straw bales, it is important to point out another
of their applications for trapping sediment. This is in providing a sediment
barrier along the downhill perimeters of small graded sites where area
restrictions or other factors prevent the use of other practices.
56
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In this case, the bales were placed along the base of a short graded
slope to prevent sediment from being washed out onto the roadway. The
bales must be placed in the same manner as prescribed for those used to
construct small traps.
SLIDE NO. 41 - BARRIER FAILURE
Close inspection is required to insure that the barrier is retaining the
sediment. Where failures occur, corrective action must be taken immediately
SLIDE NO. 42 - EXCAVATED SEDIMENT TRAP IN A
ROADWAY DITCH
Another means of trapping sediment before it enters the storm drainage
system is to excavate a pit on the upstream side of the inlet. As in the case
of all of the other traps, its function is to temporarily detain the runoff and
thereby allow some of the sediment to settle out. The buildup of sediment
at the upstream end of this pit attests to the effectiveness of this type of
trap.
SLIDE NO. 43 - LARGE EXCAVATED TRAP AROUND A
STORM DRAIN INLET
Here is an example of a large excavated sediment trap used on a
school construction site. It is an excellent example of very good planning
on the part of the engineer. This trap cost very little to construct in that
it made use of existing structures. The only additional cost incurred was
in excavating the pit. Another plus factor was that the pit was made big
enough to accommodate all of the sediment coming off the graded area without
requiring cleaning. Thus, once the sediment-yielding area is stabilized, the
the pit area can simply be filled in the rest of the way with soil and covered
with sod.
57
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Also, note the well-constructed diversion dikes leading up to the
sediment trap. Their purpose is to prevent sediment from leaving the
construction site and to divert it, instead, into the trap.
SLIDE NO. 44 - DRY SEDIMENT BASIN
Sediment basins are the most effective structures for trapping sedi-
ment. They are used on large construction sites where heavy concentrations
of both runoff and sediment are anticipated.
Sediment basins are formed by constructing an earthen dam across a
drainageway, thus causing the runoff to pond during storms. There are two
basic types of sediment basin — the dry basin and the wet basin. The basin
shown on the screen is an example of a dry sediment basin. It is designed to
only temporarily impound runoff during rainfalls.
SLIDE NO. 45 - STANDARD GALVANIZED METAL RISER PIPE
The structure is drained by a standard metal riser pipe open at the top to
handle runoff at a controlled rate during storms. Perforations are provided
along the pipe to prevent the structure from permanently ponding water. The
odd-looking device at the top of the riser pipe is an antivortex plate and
trash rack. Its purpose is to increase the intake capacity of the pipe and at
the same time to minimize the possibility of trash blockage.
SLIDE NO. 46 - RISER PIPE CONNECTED TO
HORIZONTAL BARREL
The riser pipe is connected to a metal horizontal drain pipe, called a
barrel, that conducts the water through the earthen dam.
SLIDE NO. 47 - EMERGENCY SPILLWAY
58
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An emergency spillway is provided in the event the runoff exceeds the
design capacity of the pipe structures.
A formal design by an engineer or other similarly qualified individual
is required to properly size the basin and all of its components to the
drainage area emptying into the basin. Another reason for this requirement
is safety. The failure of larger impoundments could lead to costly property
damage and even loss of life.
Close control must also be provided to insure that proper construction
practices are employed. Only suitable soils must be used to construct the
dam and a high degree of compaction must be achieved.
SLIDE NO. 48 - DRY SEDIMENT BASIN
Proper vertical positioning of riser pipe as well as good bonding
between the structure and the barrel are also very essential to the proper
performance of the structure as well as safety,
SLIDE NO. 49 - PIPING FAILURE IN A DRY SEDIMENT BASIN
Piping failures, that is, flow along the outside of the drain pipe, are
all too common in temporary dry sediment basins. A cavity at the base of
the riser pipe is the tell-tale evidence of such failure. This problem is the
result of poor bonding between the drain pipe and the soil forming the dam.
SLIDE NO. 50 - FAILED DRY SEDIMENT BASIN
If not corrected, piping will, in time, lead to the total failure of the
dam.
59
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Before constructing a sediment basin, it is advisable to consult the
state and local regulations governing their design and construction. One
can obtain these regulations from the local soil and water conservation
district, county or city public works department, or the state pollution
control agency.
SLIDE NO. 51 - SEDIMENT BASIN REQUIRING CLEANING
Another factor that is too often ignored is cleaning. Many sediment
control structures are well-conceived, designed, and constructed, but fail
to perform their required function because of the absence of follow-up
maintenance. In this case, the basin is completely filled with sediment.
The trapping efficiency has dropped to zero and incoming sediment has
unrestricted access into the riser pipe and out into the lower-lying drainage
system.
To prevent this from happening, it is essential that the erosion and
sediment plan incorporate methods for determining when a basin has filled
to its capacity and strong language as to the immediate requirement for
cleanout once this occurs.
SLIDE NO. 52 - MARKED RISER PIPE
To assist the foreman and inspector in determining when cleaning is
required, a marking should be made on the riser pipe to indicate the level
that sediment can build up to before cleaning becomes essential.
SLIDE NO. 53 - CLEANING OF A DRY SEDIMENT BASIN
60
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Dry sediment basins are usually cleaned with a backhoe or a dragline.
Smaller basins having firm foundations are sometimes cleaned with front-
end loaders.
SLIDE NO. 54 - RISER PIPE EXTENDING ABOVE DAM
Earlier, we mentioned the need to insure that the riser is positioned
properly. In inspecting construction, a point to also check for is that the
top of the pipe is at least one foot below the crest of the dam. This riser
obviously does not comply. When an emergency spillway is required, the distance
between the top of the dam and the crest of the emergency spillway must also be
at least one foot. The construction specifications for the basin must specify this
required freeboard.
SLIDE NO. 55 - BREACHED SEDIMENT BASIN
Failure to adhere to these specifications is likely to result in overtopping
during heavy storms and breaching of the dam.
SLIDE NO. 56 - WET SEDIMENT BASIN
Dry sediment basins are constructed on drainageways that only flow
during storms. Often, it also becomes necessary to dam permanent
streams in order to trap sediment. When this becomes necessary, a wet
sediment basin is constructed. In other words, a pond is created.
On large residential developments, recreational impoundments also
function as sediment traps. After the watershed is fully developed, the pond
is cleaned and stocked with fish.
Wet sediment basins, or sediment ponds as they are also called,
require a formal design and strict construction control for safety reasons.
61
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SLIDE NO. 57 - DRAGLINE CLEANING OF A SEDIMENT POND
Cleaning of a sediment pond is a costly operation requiring heavy
equipment, in this case a dragline, and an elaborate scheme to dispose of
the excavated sediment in a manner that will prevent it" from being reintro-
duced into the drainage system.
SLIDE NO. 58 - DREDGING OPERATION
On larger sediment ponds, it is necessary to use portable dredges to
clean the sediment out of the pond.
SLIDE NO. 59 - DREDGE SPOIL DISPOSAL
The dredge spoil is pumped directly from the dredge to the disposal
area. The disposal area in this case is a dry basin. Upon filling, the basin
area will be graded and, in time, will be developed into a recreational park.
SLIDE NO. 60 - CAPTION: REVIEW OF SEDIMENT CONTROL
PRACTICES
Before going to the question and answer period, let's take a quick look
at all of the practices covered in the presentation.
SLIDE NO. 61 - REPEAT OF SLIDE NO. 3
These included natural vegetative buffer areas . . . .
SLIDE NO. 62 - REPEAT OF SLIDE NO. 12
constructed vegetative buffers
SLIDE NO. 63 - REPEAT OF SLIDE NO. 8
62
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natural woodland areas
SLIDE NO. 64 - REPEAT OF SLIDE NO. 19
vegetative contour strips or buffers
SLIDE NO. 65 - REPEAT OF SLIDE NO. 21
sod inlet filter ....
SLIDE NO. 66 - REPEAT OF SLIDE NO. 29
gravel inlet filter
SLIDE NO. 67 - REPEAT OF SLIDE NO. 34
interceptor dike
SLIDE NO. 68 - REPEAT OF SLIDE NO. 35
sandbag trap
SLIDE NO. 69 - REPEAT OF SLIDE NO. 37
straw bale trap
SLIDE NO. 70 - REPEAT OF SLIDE NO. 40
straw bale barrier
SLIDE NO. 71 - REPEAT OF SLIDE NO. 43
excavated trap .....
63
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SLIDE NO. 72 - REPEAT OF SLIDE NO. 44
dry sediment basin. ....
SI JDK NO. 73 - REPEAT OF SLIDE NO. 56
and the wet sediment basin or sediment pond.
This concludes the presentation on controlling erosion during construction,
NOTE: TURN LIGHTS ON
Are there any questions or comments on the sediment control practices
covered in this presentation?
64
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VISUALS FOR PRESENTATION NO. 7
SLIDE NO. 1
SLIDE NO. 2
SLIDE NO. 3
SLIDE NO. 7
SLIDE NO. 8
^ . "*-. *:
SLIDE NO. 9
,
SLIDE NO. 10
-.
SLJDL NO. 11
SLIDE NO. 12
SLIDE NO. 13
SLIDE NO. 14
SLIDE NO. 15
j.i.'
65
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SLIDE NO. 16 SLIDE NO. 17 SLIDE NO. 18
SLIDE NO. 19 SLIDE NO. 20 SLIDE NO. 21
SLIDE NO. 22
66
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SLIDE NO. 31
SLIDE NO. 32
SLIDE NO. 33
SLIDE NO. 40
SLIDE NO. 41
SLIDE NO. 42
67
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SLIDE NO. 46
SLIDE NO. 47
SLIDE NO. 48
B
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SLIDE NO. 61
SLIDE NO. 62
SLIDE NO. 63
SLIDE NO. 64
I
SLIDE NO. 65
SLIDE NO.
I
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APPENDIX B
SAMPLE FOR A CONVENTIONAL PRESENTATION
70
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PRESENTATION NO. 7
CONTROL OF SEDIMENT
GENERATED ON CONSTRUCTION SITES
HANDOUT
71
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ACKNOWLEDGEMENT
Acknowledgement is hereby made that this material was pre-
pared under the assistance of a jointly sponsored Grant program
by the U.S. Environmental Protection Agency and the State of
Maryland.
72
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INTRODUCTION
By the "Control of Sediment Generated on Construction Sites, "
we mean the trapping of sediment on the construction site as near its
point of origin as possible. In an indirect sense, one might think of
erosion control practices as doing this, in that they are designed to
reduce soil erosion which is the source of sediment. However, a
point to keep in mind is that one can only expect reasonable erosion
control. Thus, even with the best plan, some erosion must be antici-
pated and therefore some sediment will be generated.
In an erosion and sediment control plan, we establish two separate
lines of defense against sediment damage. The first defense is the ero-
sion control which reduces the amount of sediment that will be generated
and the second is the sediment control which prevents much of the sedi-
ment from uncontrollable soil erosion from leaving the construction
area. To be fully effective in preventing costly sediment damage and,
at the same time, to prevent ugly "erosion and minimize the loss of
precious topsoils, both defenses must be used.
Sediment control actually begins during the planning and design
phases of construction, starting with layout or alignment studies and
culminating with the preparation of an erosion and sediment control
plan. However, in this lesson, we will deal only with sediment con-
trol during construction. This involves the use of both vegetative and
structural practices, some very simple and others more complicated,
to trap most of the sediment before it leaves the construction site.
Sediment control practices are designed to slow the flow of water
either by spreading, ponding, or filtering. By so doing, the ability of
the water to transport sediment is reduced and sediment settles out of
suspension. The amount of sediment removed from the runoff is depen-
dent upon three factors: First, the speed that the water flows through
the trap; secondly, the length of time the water is detained; and last, the
the size and weight of the sediment particle carried into the trap.
There are two types of sediment practices — vegetative and
structural.
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VEGETATIVE PRACTICES
The vegetative practices include:
(1) Natural vegetative buffers
(2) Woodland areas
(3) Graded vegetative buffers
(4) Contour strips
(5) Sod inlet filters
Natural Vegetative Buffer
A natural vegetative buffer is a strip of natural vegetation pre-
served along the downhill perimeter of the graded area to slow and
filter overland flow. This is one of the more effective and economical
methods of removing sediment from overland flow. The preservation
of such a buffer is most essential along waterways.
The need for preserving natural buffer areas must be recognjzed
at the planning and design stage of development and these areas must
be prominently displayed on the construction plans as off-limits to all
construction activity. Except for essential roadway crossings, no con-
struction must be allowed within the buffer area. The contractor must
not be allowed to stockpile soil on a floodplain. Not only is the chance
of sediment pollution from overland flow greatly increased by this
action, but the prospects of damaging flooding coupled with very severe
erosion is greatly enhanced.
All construction traffic must also be kept off the buffer. A dense
healthy stand of vegetation must be maintained in order for the buffer
to effectively filter runoff.
Because of its low, dense growth and other factors, grass is the
best vegetative filter material. Thick, low-growing legumes such as
white or red clover are also effective filters. Even during the dormant
winter months, the mat provided by the dead foliage still slows the flow
of runoff and traps sediment before it reaches the drainage system.
Woodland Areas
The thick mat of litter covering natural woodland areas also pro-
vides a high degree of filter action as well as aiding in the absorption
-------
of runoff. Considerable care must be exercised, however, in utilizing
woodland areas for trapping sediment. The deposition of several inches
or more of sediment around a tree may reduce the oxygen supply to the
shallow feeder roots to such an extent that the tree will die. It is best
to use such areas only for the filtering of overland flow and not for fil-
tering concentrated flow containing heavy concentrations of sediment.
It is a simple matter to reestablish a cover of grass destroyed by sedi-
mentation, but not so a stand of trees.
Graded Vegetative Buffer
When it is not possible to preserve a natural vegetative buffer,
one can be constructed. It is then referred to as a graded vegetative
buffer. Planning for the construction must be done during early design
stages. The flatter and the longer the buffer area can be made, the
more sediment it will retain. A positive grade of two percent will pro-
vide controlled spreading and runoff.
Timely establishment of vegetation on the buffer is also a must if
the buffer is to be fully effective. A thick stand of grass slows the over-
land flow and filters out sediment. In addition to filtering the flow, the
vegetation allows more water to be absorbed by the soil and thus decreases
the ability of the runoff to transport sediment.
When grading must be performed along a waterway, stage the work
so that grading and vegetative stabilization are completed along the side
of the waterway first.
Vegetative Contour Strips
The use of vegetative contour strips is a practice borrowed from
the farmer. It is used to break the flow of runoff on long hillsides. It
involves the establishment of strips of vegetation, usually grass sod,
along the ground contour at regular intervals up the slope. These buffer
strips slow the flow and reduce the amount of runoff, thereby reducing
erosion, while at the same time trapping much of the sediment generated
from unpreventable erosion.
Sod Inlet Filter
The sod inlet filter is another vegetative practice used to control
sediment. It consists of pads of sod placed around the storm drain inlet
and works on the same principle as the vegetative buffer areas previously
discussed. The grass slows the flow of water into the inlet and filters
out appreciable amounts of sediment. The size of the sodded area is
varied depending upon the amount of runoff expected at the inlet. This
practice should only be used to handle light concentrations of sediment.
It can best be used after final grading is complete and during the estab-
lishment of a vegetative cover.
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STRUCTURAL PRACTICES
Structural practices include:
(1) Dikes and filters
(2) Sediment traps
(3) Sediment basins
On urban construction sites and on major highway projects where
storm drains are used, the prevention of sediment damage to the drainage
system becomes a particularly important task. To provide for drainage
during construction, storm drains must be installed well ahead of final
grading. As a result, sediment generated on the graded areas is given
unrestricted access to the drainage system downstream of the construc-
tion site. Failure to take adequate measures to trap much of the sedi-
ment before it reaches the storm drainage system will lead to extremely
costly damage to the storm drain as well as to the waterways lying below
the outfall. The cost to remove the sediment from a-stream can run to
several thousands of dollars and, in many instances, will be borne by
the taxpayer. Consider also the damage to the trees and other vegeta-
tion as well as the total destruction of the stream ecology which cannot
be measured in dollars and cents.
Gravel Inlet Filter
In constructing a gravel inlet filter,- coarse gravel or crushed stone
is piled around an inlet to form a barrier that will both temporarily im-
pound runoff and act as a filter. In addition to providing a certain amount
of filtering action, gravel or crushed stone is highly resistant to erosion
should overtopping occur during heavy storms.
The configuration of the gravel inlet filter will depend upon the
type of inlet being protected. In the case of a standard curb inlet, the
stone is placed directly in front of the inlet opening. To keep the stone
from falling into the storm drain, concrete blocks are inserted into the
opening. A board placed across the opening with a space of at least
one-half inch at the top and bottom will also work.
Prompt maintenance is a very essential requirement for the suc-
cessful operation of any sediment control structure, in order for an
inlet filter to be fully effective, it must be able to temporarily pond and
filter the runoff. Completely clogged with sediment, it can do neither.
When clogging occurs, the sediment is simply carried over the stone
and into the storm drain. To prevent this from happening, the trap must
be inspected after each storm and cleaned prior to becoming ineffective —
not after. Furthermore, the sediment that is removed must not be dis-
posed of back on the graded right-of-way, but instead in a stabilized
76
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area away from the grading where the sediment cannot be reintroduced
into the drainage system.
On roadway rights-of-way, an interceptor dike is often used to
intercept runoff coming down the graded roadway and divert it into
storm drain inlets protected by gravel filters. As well as aiding in the
trapping of sediment, the interceptor dike also helps control erosion by
diverting runoff away from the graded surface.
Sandbag Sediment Trap
A quick and economical method of temporarily disrupting flow and
trapping the coarser sediment particles is a sandbag sediment trap con-
structed across a ditch upstream of a storm drain inlet. By positioning
these barriers at regular intervals along the ditch, a high degree of
trapping efficiency can be achieved. The sandbags are filled with soil
or stone and are stacked in an interlocking fashion to provide additional
strength for resisting the force of the flowing water.
A major cause of failure for many of the temporary sediment traps
is piping. This is the flow of water beneath the structure rather than
through or over the top of the barrier. By setting the sandbags in a
trench excavated a minimum of six inches in depth and by firmly tamping
soil along the uphill face of the bags, the chance of piping failure is
greatly reduced.
Straw Bale Sediment Trap
Straw or hay bales are also used to construct small temporary
barriers to trap sediment. Straw bale traps are a fast and economical
means of providing a temporary sediment trap. Although they function
well when properly installed, straw bale traps deteriorate rather rapidly.
One means of prolonging the service life of the trap is by using wire-tied
bales rather than those tied with twine. When only twine-tied bales are
available, the same effect can be achieved by securely wrapping them
with sturdy wire at the location of the twine.
In constructing the trap, the bales are laid on their sides and
staked in place. At least two wooden or metal stakes are driven through
each bale and into the ground.
As in the case of sandbag traps, piping beneath the structure can
render the trap ineffective. To prevent this, the straw bales are also
set in a trench excavated to a depth of at least six inches and excavated
soil is compacted along the upstream face.
Like all other sediment traps, straw bale and sandbag traps also
require periodic inspection and very prompt maintenance if they are to
continuously function. Again, sediment removal does not mean shoveling
77
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the sediment off to one side where the next storm will send it directly
back into the drainage system. Instead, properly dispose of it in a safe
area.
Straw bales can also be used to provide a sediment barrier along
the downhill perimeters of small graded sites where area restrictions
or other factors prevent the use of other practices. , When used in this
manner, the bales provide a barrier that slows and filters overland flow.
In constructing a straw bale barrier, the bales are placed in the
same manner as prescribed for straw bale traps used in ditches and
other small waterways.
jCxcavated Sediment Trap
Another means of trapping sediment before it enters the storm
drainage system is to excavate a pit on the upstream side of the inlet.
As in the case of all of the other traps, its function is to temporarily
detain the runoff and thereby allow some of the sediment to settle out.
This type of trap costs very little to construct in that it makes use of
existing structures. The only additional cost incurred is in excavating
the pit.
Sediment Basins
Sediment basins are the most effective structures for trapping
sediment. They are used on large construction sites where heavy icon-
centrations.of both runoff and sediment are anticipated. There are two
types of sediment basins — the dry basin and the wet basin. Both are
constructed by damming a waterway. Dry sediment basins are con-
structed on waterways that flow only during storms. Wet basins, on the
other hand, are constructed on both intermittent and permanent water-
ways.
Dry basins and, in most instances, wet basins are drained by a
standard metal riser pipe open at the top to handle runoff at a controlled
rate during storms. In dry basins, perforations are provided along the
pipe to prevent the structure from permanently ponding water. An anti-
vortex plate and trash rack are attached at the top of the riser pipe. Their
purpose is to increase the intake capacity of the pipe and at the same
time to minimize the possibility of trash blockage.
For safety reasons, the top of the riser must be positioned properly.
In small basins, the top of the pipe must be at least one foot below the
crest of the dam. When an emergency spillway is required, the distance
between the top of the dam and the crest of the emergency spillway must
also be at least one foot. Failure to adhere to these specifications is
likely to result in overtopping during heavy storms and breaching of the
dam.
78
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The bottom of the riser pipe is connected to a metal horizontal
drain pipe, called a barrel, that conducts the water through the earthen
dam. Proper bonding between the structure and the barrel is also very
essential to the proper performance of the structure as well as safety.
Failure to provide adequate bonding leads to piping failure. This is the
flow of water, and resulting erosion, along the outside of the barrel.
A cavity at the base of the riser pipe is the tell-tale evidence of such
failure.
A formal design by an engineer or other similarly qualified indi-
vidual is required to properly size the sediment basin and all of its
components to the drainage area emptying into the basin. Another rea-
son for this requirement is safety. The failure of larger impoundments
could lead to costly property damage and even loss of life.
Close control must also be provided to insure that proper con-
struction practices are employed. Only suitable soils must be used to
construct the dam and a high degree of compaction must be achieved.
Before constructing a sediment basin, it is advisable to consult
the state and local regulations governing their design and construction.
One can obtain these regulations from the local soil and water conser-
vation district, county or city public works department, or the state
pollution control agency.
Periodic cleaning is essential to the successful functioning of a
sediment basin. Many sediment basins are well-conceived, designed,
and constructed, but fail to perform their required function because of
the absence of follow-up maintenance. To prevent this from happening,
it is essential that the erosion and sediment plan incorporate methods
for determining when a basin has filled to its capacity and strong lang-
uage as to the immediate requirement for cleanout once this occurs.
To assist the foreman and inspector in determining when cleaning
is required for a dry basin, a marking should be made on the riser pipe
to indicate the maximum allowable sediment level in the structure.
Cleaning of a sediment pond is a costly operation requiring heavy
equipment and an elaborate scheme to dispose of the excavated sediment
in a manner that will prevent it--from being reintroduced into the drain-
age system.
Dry sediment basins are usually cleaned with a backhoe or a drag-
line. Smaller-ba'sins having firm foundations are sometimes cleaned
with front-end loaders. For wet basins or sediment ponds, it is some-
times necessary to use portable dredges.
79
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APPENDIX C
SAMPLE AUDIOVISUAL SCRIPT
80
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PART I - CONTROL OF SEDIMENT
GENERATED ON CONSTRUCTION SITES
AUDISCAN PROGRAM
page i
SCRIPT
Client :
Hittnian
.. Lesson #8
Frame
N anration
Visuals
Music up and under.
Voice over loudspeaker:
30 seconds to launch and counting
(cause)
Slide:
ROCKET ON LAUNCH PAD
25 . . . 24 . . ., on board computer indicates
malfunction in ground-to-air communications re-
corder. Switch to first back-up system.
Computer now indicates recorder functioning
normally. Continue with launch.
Slide:
CONTROL ROOM
blastoff.
(sound effect rocket blasting off)
Slide:
ROCKET GUSHING FLAMES
81
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page
AUDISCAN PROGRAM
SCRIPT
Client :
Progi
Hittman
.. Lesson #8
Frame
Narration
Visuals
6. Sound effect and music.
7. Sound effect and music under
As in the exploration of space, here on earth
man has learned the value of having good back-
up systems or defenses, should a problem arise.
Slide of earth from space.
9. In this program we are going to learn about the
systems or defenses used to control sediment
generated on construction sites.
Title Slide:
CONTROL OF SEDIMENT
GENERATED ON
CONSTRUCTION SITES
Part I
10. By controlling sediment, we mean trapping in on
the construction site as near to its point of
origin as possible.
Slide showing erosion trapped at the
construction site.
3-33 (Slide number)
82
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AUDISCAN PROGRAM
page
SCRIPT
Client :
Progi
Hittman
Lesson #8
Frame
Narration
V isuals
11. Indirectly, we think of erosion control practices
as doing this, in that they are designed to re-
duce soil erosion, which is the source of sedi-
ment.
Slide of an erosion control practice.
19-46
12. Remember however we can only expect reasonable
erosion control,
Slide of 2nd erosion control practice
SUPER
Reasonable Control
17-72
13. because even with the best plan, some erosion
must be anticipated and as a result some sedi-
ment generated.
Slide showing a small amount of sedi-
ment which was generated even though
erosion plan was used.
4-36
14. In an erosion and sediment control plan, two
separate systems or defenses against sediment
damage are established.
Simple art
#1
CONTROL PLAN
#2
SEDIMENT
15. The first defense is erosion control . . .
Slide of erosion control practice
Super
EROSION CONTROL
14-49
83
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AUDISCAN PROGRAM
page
SCRIPT
Client :
Prog re
Hittman
Lesson #8
Frame
N anration
V isuals
16. It reduces the amount of sediment which will be
generated.
Slide of soil interceptor dike
10-19
17. The second defense is sediment control . . .
Slide of sediment control device
Super Sediment control
3-2
18. which prevents much of the sediment from leaving
the construction area.
Slide of straw bale barrier
3-80
19. To be fully effective in preventing costly sedi-
ment damage and at the same time . . .
Slide of sediment damage to pond
4-69
20. prevent ugly erosion and minimize the loss of
soil, both defenses must be used.
Slide of erosion.
AG-57
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AUDISCAN PROGRAM
page 5
SCRIPT
Client :
Prog ram:
Hittman
Lesson #8
Frame
N a r ration
V isuals
21. How do we keep this sediment from damaging the
environment?
Slide showing a mass of sediment
in roadway ditch
4-44
22. By using vegetative and structural practices,
some very simple,
Slide of straw bale trap
3-61
23. and others more complicated, that trap most of
the sediment before it leaves the construction
site.
Slide of structural practice
Super: STRUCTURAL PRACTICES
3-76
24. We are now going to examine some of the principle
involved in controlling sediment.
Title Board.
PRINCIPLES FOR CONTROLLING SEDIMENT
25. Sediment is trapped by slowing the flow of water.
Slide of sediment trao spreading the
water.
3-14
85
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AUDISCAN PROGRAM
page
SCRIPT
Client :
Program:
Hittman
Lesson #8
Frame
Narration
Visuals
26.
By slowing, the ability of the water to trans-
port sediment is reduced and sediment settles
out of suspension.
Slide showing sediment which has
settled out of suspension.
3-167
27.
The amount of sediment removed from the runoff
is dependent upon 3 factors: first the speed
that water flows through the trap . .
Slide of water flowing through trap.
Super
SPEED OF FLOW
3-84
28. Second, the length of time the water is detained
Slide of water in trap.
Super
TIME DETAINED
3-88
29, And third, the size and weight of the sediment
particle carried into the trap.
Photo — close-up of water — showing
sediment particles in water.
3-172
30. With regard to the first two factors, the
slower the flow of water, and the longer it is
detained, the greater the quantity of sediment
deposited.
Title Board:
1. Speed of Flow
2. Time Detained
86
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AUDISCAN PROGRAM
page 7
SCRIPT
Client:
Hittman
Program: Lesson #8
Frame
Narration
Visuals
31.
The size and weight of the sediment particles
determine the speed at which they settle out
of suspension. The larger and heavier a parti-
cle, the faster it settles out.
ART:
Large pebble and small pebble
falling in water.
32.
Efficience of sediment trapping is expressed as
the percentage of sediment removed from the
runoff.
Let's stop at this point and go to Question 1 in
your workbooks.
TB
_,,-. . Trapped Sediment inn°
Efficiency = — x lUO-s
Total Sed. Runoff
33.
Open workbook to page 1.
(STOP)
34.
35.
Now that we've reviewed the basic principles
governing the function of sediment traps, let's
look at some of the practices used to trap
sediment.
Slide of sediment pond
3-83
Various types of vegetative buffers are used,
These are:
^Natural veaetative buffers
oGraded vegetative buffers
oContour stripping
"Woodland areas
°Sod inlet filters
TB
Natural vegetative buffers
Graded vegetative buffers
Contour stripping
Woodland areas
Sod i.r.le" ^liters
87
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AUDISCAN PROGRAM
page
SCRIPT
Client
Progi
Hittman
.. Lesson #8
Frame
Narration
Visuals
36.
Leaving a vegetated buffer at the base of a
steep slope is an effective means of trapping
sediment.
Slide of Buffer at Base of Steep Slope
9-22
37.
This involves preserving a strip of natural vege-
tation along the sides of the waterway to slow
and filter overland flow coming from higher-
lying graded areas. This is one of the more
effective and economical methods of removing
sediment from overland flow.
Slide of natural vegetative buffer
area along a stream.
25-2
38.
The need for preserving natural buffer areas
must be recognized at the planning and design
stage of development and these areas must be
prominently displayed on the construction plans
as off limits to all construction activity.
Slide - men at drawing board.
39. Except for essential roadway crossings, no con-
struction must be allowed within the buffer area.
Slide of utility construction
40. Vegetation damaged by uncontrolled construction
activity, whether it be grading practices, con-
struction traffic or other means, cannot effic-
iently filter overland flow.
Hold frame 39
25-33
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AUDISCAN PROGRAM
page
SCRIPT
Client :
Hittman
Prog ram:
Lesson #8
Frame
Narration
V isuals
41.
Good planning by the engineer and careful grading
by the contractor could have preserved a pro-
tective buffer along this stream and prevented
serious sediment pollution. Instead, all of the
vegetation was destroyed along the stream bank
and the spoil from the utility excavation was
oushed into the stream.
Slide of utility construction along
a stream.
25-20
42.
Where it is not practical to preserve natural
vegetated buffers or where they do not exist,
provisions should be made for the construction
of a buffer.
Slide of Sediment deposited on buffer.
9-17
43. .Planning for construction of buffers must be done
during early design stages.
Slide of contractor on site checking
the exact location of a buffer.
9-35
44.
The flatter and the longer the buffer area can
be made, the more sediment it will retain. A
positive grade of two percent will provide con-
trolled spreading and runoff.
Slide of long flat buffer area.
9-10
15. Timely establishment of vegetation on the buffer
is a must to provide effective sediment trapping.
Slide of vegetative buffer area
Super
VEGETATIVE BUFFER
9-6
89
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AUDISCAN PROGRAM
page 10
SCRIPT
Client:
Prog rom:
Hittman
Lesson #8
Frame
Narration
Visuals
46. A Thick stand of grass slows the overland flow
and filters out sediment. In addition to
filtering the flow . . .
Slide of sediment trapped by a buffer
9-18
47.
the vegetation allows more water to be absorbed
by the soil and thus decreases the ability of
the runoff to transport sediment.
Slide showing close up of sediment
trapped by grass
9-13
48.
This flattened slope and grass are very effective
in trapping sediment from the overland flow
coming off the graded area.
Slide of sediment trapped by grass
below a graded area.
9-3
49.
Staged grading is a means of providing for the
establishment of a vegetative buffer along a
waterway.
Slide of sodded drainage way adjacent
to a graded area.
14-34
Here a waterway was constructed and stabilized
•vith vegetation prior to the beginning of road-
way construction. The resulting vegetative
buffer will filter the runoff coming from the
Another slide of sodded drainage way
adjacent to graded area.
9-4
90
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AUDISCAN PROGRAM
page 11
SCRIPT
Client :
Prog ram:
Hittman
Lesson #8
Frame
Narration
Visuals
51. This roadway construction site reflects very
poor planning on the part of the engineer. The
channel realignment and buffer strip were con-
structed before the embankment in the foreground.
lide of grassed embankment above a
denuded buffer strip and channel
5-19
52.
The buffer strip was not vegetated prior to con-
struction of the embankment.
Hold frame 51
5-19
53.
By failing to promptly vegetate the buffer strip,
thousands of tons of sediment were washed into
the lower-lying waterway.
Hide of sediment washed into waterway.
5-24
The heavy deposition of sediment in the channel
forced the stream to meander and erode the bank.
As a result, additional sediment was introduced
into the waterway.
Slide of sediment-clogged channel and
resulting bank erosion.
5-23
.•5.
It's time for a review.
answer question 2.
Open your workbooks and
Question 2
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AUDISCAN PROGRAM
page 12
SCRIPT
Client :
Prog rom:
Hittman
Lesson #8
Frame
Narration
Visuals
Contour stripping involves the establishment of
strips of dense vegetation, along the ground
contour at regular intervals up the slope.
Slide of vegetative contour strips.
Art
57.
These buffer strips slow the flow and reduce the
amount of runoff, thereby reducing erosion, while
at the same time trapping much of the sediment
generated from unpreventable erosion.
Slide of contour farming
58.
The use of a sodded buffer near the base of this
short slope serves the same function as contour
strips.
Slide of vegetative "Right-of-way1
buffer.
3-104
59.
The thick mat of litter covering natural wood-
land areas also provides a high degree of fil-
tering action, as well as aiding in the absorp-
tion of runoff.
Slide of woodland litter
1-197
60. Considerable care must be exercised, however, in
utilizing woodland areas for trapping sediment.
Slide of woodland area
1-135
92
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AUDISCAN PROGRAM
page is
SCRIPT
Client :
Hittman
Progi
Lesson
Frame
Narration
Visuals
61.
The deposition of a couple of inches or more of
sediment around a tree may reduce the oxygen
supply to the shallow feeder roots to such an
extent that the tree will die.
Slide of sediment deposition in a
woodland area.
4-9
62. It is best to use such areas only for the filter-
ing of overland flow and not for filtering
concentrated flow containing heavy amounts of
sediment.
.Slide showing heavy deposition in
wooded area.
4-7
53. Remember, it is a simple matter to re-establish
a cover of grass destroyed by sedimentation,
but not so a stand of trees.
Slide of tree damage from sediment
deposition.
4-10
A vegetative practice used at storm drain inlets
is the sod inlet filter.
Slide showing sod inlet filter
3-97
'5. This filter is made up of pads of sod placed
around the storm drain inlet. It works on the
same principle as the vegetative buffer.
Slide of sod inlet filter
Hold frame 64
93
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AUDISCAN PROGRAM
page 14
SCRIPT
Client :
Program:
Hittman
Lesson #8
Frame
Narration
Visuals
66. The grass slows the flow of water into the inlet
and filters out appreciable amounts of sediment.
Close up on inlet in action.
3-103
67.
The size of the sodded area is varied, depending
upon the amount of runoff expected at the inlet.
Slide of large sodded inlet filter area.
3-59
68.
This practice should only be used to handle light
concentrations of sediment. It can best be used
after final grading is complete and during the
establishment of a vegetative cover.
Slide of sod inlet filter
3-107
69.
Go now to Quetsion 3.
Questions 3
70.
Because of its low, dense growth and other fac-
tors , grass is the best vegetative filter mater-
ial. Thick, low-growing legumes such as white
or red clover are also effective filters.
Vegetative buffer
9-19
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AUDISCAN PROGRAM
page
15
SCRIPT
Client :
Hittman
Progi
Lesson #8
Frame
Narration
V isuals
'i.
Even during the dormant winter months, the mat
provided by the dead foliage still slows the flow
of runoff and traps sediment before it reaches
the waterway.
Slide showing mat of dead foliage like
legumes.
16-90
2.
Once the flow becomes concentrated, as it does
in ditches and other waterways, the trapping of
sediment becomes much more difficult and expen-
sive.
Slide of concentrated runoff carrying
sediment.
4-31
3.
In addition to vegetative practices, structural
practices must be utilized to prevent sediment
from entering the natural drainage system.
Gravel inlet filter
3-74
Up to this point we've learned about the princi-
ples of trapping sediment.
Slide of sediment trapped in a
vegetative buffer
3-140(1)
>• We learned that the amount of sediment removed Slide of sediment in urban pond
from runoff water is dependent upon three factors
the speed that water flows through the trap . . .
3-168
95
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AUDISCAN PROGRAM
page
16
SCRIPT
Client :
Progro
Hittman
Lesson #8
Frame
Narration
Visuals
76. The length of time the water is detained
Sediment basin
3-144
77. And the size and weight of the sediment particle
carried into the trap.
>lide of sediment bedload
3-171
78. We also looked at the vegetative practices for
controlling sediment, including
Slide of sediment deposited on a
buffer
9-16
79. natural vegetative buffers . . .
Slide of natural vegetative buffer
9-2
80. graded vegetative buffers
iame slide as # '36.
9-22
96
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AUDISCAN PROGRAM
page
17
SCRIPT
Client:
Program:
Hittman
Lesson #8
Frame
Narration
Visuals
81. Woodland areas and sod inlet filters.
Slide of sod inlet filter
3-97
82. In part two we'll learn about the structural
practices for controlling sediment on the con-
struction site. But first, let's take a break.
Slide of sediment basin
3-86
END OF PART I
97
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APPENDIX D
SAMPLE AUDIOVISUAL WORKBOOK
98
-------
CONTROL OF SEDIMENT
GENERATED ON
CONSTRUCTION SITES
WORKBOOK
To be used in conjunction
with the audio-visual program
99
-------
ACKNOWLEDGEMENT
Acknowledgement is hereby made that this material was pre-
pared under the assistance of a jointly sponsored Grant program
by the U.S. Environmental Protection Agency and the State of
Maryland.
100
-------
CONTENT
I. BASIC PRINCIPLES OF CONTROLLING SEDIMENT
II. VEGETATIVE PRACTICES
A. Natural Vegetative Buffers
B, Graded Buffers
C. Contour Stripping
D. Woodland Areas
E. Sod Inlet Filters
III. STRUCTURAL PRACTICES
A. Filters and Dikes
1. Gravel Inlet Filter
2. Interceptor Dike
B. Sediment Traps
1. Sandbag Trap
2, Straw Bale Trap
3. Straw Bale Barrier
C. Sediment Basins
1. Dry
2. Wet - Sediment Pond
IV. REVIEW QUIZ
101
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BASIC PRINCIPLES OF CONTROLLING SEDIMENT
A. Erosion control is the first line of defense.
It reduces the amount of sediment that will be
generated.
B. Sediment control is the second line of defense.
It prevents much of the sediment from uncontrol-
lable soil erosion from leaving the construc-
tion site.
C. Sediment traps are designed to slow the flow
of water. This reduces the ability of the water
to transport sediment, and the sediment settles
out of suspension.
D. The amount of sediment removed from the runoff
is dependent upon these three factors:
1. Speed that the water flows through the trap.
2. Length of time the water is detained.
3. Size and weight of the sediment particle car-
ried into the trap.
The slower the flow of water and the longer it
is detained, the greater will be the quantity of
sediment deposited. The size and weight of the
sediment particles determine the speed at which
they settle out of suspension. The larger and
heavier a particle, the faster it settles out.
102
-------
E. Efficiency of sediment trapping is expressed as
the percent of sediment removed from the runoff
Amount trapped
% Efficiency= x 100
Total Load
II. VEGETATIVE PRACTICES
A. Natural Vegetative Buffers
1. A vegetative buffer at the base of a steep
slope is an effective means of trapping sed-
iment .
2. This involves preserving a strip of natural
vegetation along the sides of a waterway to
slow and filter overland flow coming from
higher-lying graded areas.
3. This is one of the more effective and eco-
nomical methods of removing sediment from
overland flow.
4. Except for essential roadway crossings, no
construction should be allowed within the
buffer area.
B. Graded Buffers
1. Provisions for construction must be made dur-
ing early design stages of development.
2. The flatter and longer it is, the more sedi-
ment it will retain.
103
-------
3. A positive grade of at least two percent
should be provided to prevent ponding.
4. Timely establishment of vegetation on the
buffer is a must in order to provide eff-
ective sediment trapping.
C. Contour Stripping
1. A method borrowed from the farmer.
2. It is used to break the flow of runoff on
long hillsides.
3. It involves the establishment of strips of
vegetation, usually grass sod, along the
ground contour at regular intervals up the
slope .
4. These strips slow the flow and reduce the
amount of runoff, thus reducing erosion and
trapping much of the sediment generated
from unpreventable erosion.
D. Woodland Areas
1. Woodland litter can provide a high degree
of filtering action as well as aiding in
the absorption of runoff, but care must be
exercised because the deposition of a few
inches of sediment around a tree can cause
it to die.
104
-------
2. Use woodland areas only for the filtering
of overland flow.
E. Sod Inlet Filter
1. Made up of pads of sod placed around the
storm drain inlet.
2. The grass slows the flow of water into
the inlet and filters out appreciable
amounts of sediment.
3. The size of the sodded area is varied
depending upon the amount of runoff ex-
pected at the inlet.
4. This practice should only be used to
handle light concentrations of sediment.
5. Best used after final grading is complete
and during the establishment of a vegeta-
tive cover.
III. STRUCTURAL PRACTICES
A. Filters and Dikes
1. Gravel Inlet Filter
a. Used at storm drain inlets.
b. Made of coarse gravel or crushed stone
c. Will temporarily impound runoff.
105
-------
d. Provides a certain amount of filter-
ing action.
e. Is highly resistant to erosion.
f. Standard concrete building blocks
are placed on the inside of the gravel
filter to keep stones from being washed
into the storm drain inlet.
g. The configuration of the filter will
depend upon the type of inlet being
protected.
h. Prompt maintenance is very essential.
2. Interceptor Dike
a. Used on roadway rights-of-way.
b. Intercepts runoff coming down the graded
roadway and diverts it into storm drain
inlets protected by gravel filters.
c. Used with gravel inlet filter to increase
trapping efficiency.
d. Helps control erosion by diverting run-
off away from the graded surface.
106
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B. Sediment Traps
1. Sandbag Sediment Trap
a. A quick and economical method of tempor-
arily disrupting flow and trapping the
coarser sediment particles.
b. A high degree of trapping efficiency can
be achieved by positioning these barri-
ers at regular intervals along the ditch.
c. Bags are filled with soil or stone and
stacked in an interlocking fashion which
provides additional strength for resist-
ing the force of the flowing water.
d. Piping is a major cause of the failure
of many temporary sediment traps.
e. The sandbags should be set in a trench
at least six inches in depth. This will
greatly reduce the chance of piping fail-
ure.
f. Inspection and prompt maintenance is required,
2. Straw Bale Sediment Trap
a. Fast and economical temporary trap.
b. Made of bales of straw or hay.
c. Deteriorates rapidly.
d. Can increase trap effectiveness by using
wire-tied bales.
107
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e. When constructing the bales are laid
on their sides and staked into place.
d. Piping can render the trap ineffective.
f. Straw bale trap should be entrenched
at least six inches and excavated soil should be
compacted along the upstream face.
g. Inspection and prompt maintenance is re-
quired .
Straw Bale Perimeter Barrier
a. Used to provide a sediment barrier
along the downhill perimeters of small
graded sites where area restrictions
or other factors prevent the use of
other practices.
b. Close inspection is required.
Excavated Sediment Trap
a. Its function is to temporarily detain
the runoff and thereby allow some sed-
iment to settle out.
b. Costs little to construct.
c. Once the sediment-yielding area is sta-
bilized, the pit area can, in some instances,
be filled in with soil and covered with sod.
108
-------
C. Sediment Basins
1. Sediment basins are the most effective
structures for trapping sediment.
2. Used on large construction sites where
heavy concentrations of both runoff and
sediment are anticipated.
3. Dry Sediment Basin
a. Designed to only temporarily impound
runoff during rainfalls.
b. It is drained by a standard metal
riser pipe with perforations which
allow the water to be released at a
controlled rate.
c. It requires a formal design for size
and safety reasons.
d. Only suitable soils must be used to
construct the dam.
e. A high degree of compaction must be
achieved.
f. Proper positioning of the riser pipe
is essential to proper performance.
g. Piping failures are too common in tempor-
ary dry sediment basins.
109
-------
h. Consult state and local regulations
governing their design and construction
prior to starting to build one.
i. Periodic cleaning is essential if the basin
is to do its job.
(1) usually cleaned with a backhoe or
dragline
(2) smaller basins with firm founda-
tions are sometimes cleaned with
front-end loaders
j. Construction specifications for the ba-
sin must specify the required freeboard -
the vertical distance between the crest of
the emergency spillway at the top of
the dam.
k. Failing to provide enough freeboard will
result in overtopping during heavy
storms and breeching of the dam.
Wet_Basin - Sediment Pond
a. Used when it becomes necessary to dam
permanent streams in order to trap sedi-
ment.
b. On large residential developments, re-
creational impoundments also function as
sediment traps.
110
-------
c. Requires a formal design and strict
construction control for safety
reasons.
d. Cleaning a wet sediment basin is costly
(1) dragline is used.
(2) portable dredges used on large
ponds.
111
-------
Fill in the blanks
1. E c is the first
line of defense. It the amount of
sediment that will be generated.
2. S c is the second
line of defense.
3. Sediment traps are designed to slow the flow of
4 . The amount of removed from the
runoff is dependent upon three factors:
a. S that the water flows
through the t .
b. L of time the water is
c. S and w of the
sediment particles carried into the trap.
112
-------
QUESTIONS 2
Multiple Choice
1. The best vegetative filters are
a. legumes b. grasses
c. trees d. periwinkle.
answer(s)
2. No construction should be allowed within a buffer
area
a. at all.
b. except for essential loadway construction.
c. except for residentiaJ construction.
d. except for normal roacway construction.
answer(s)
True or False
Leaving a buffer at the base of a steep
slope is an effective means of trapping
sediment.
A buffer speeds the flow of runoff coming
off a steeper slope.
The flatter and longer a buffer area, the
more sediment it will retain.
Adding vegetation to a buffer area increases
its ability to trap sediment.
To prevent ponding, i positive grade of at
least two percent should be provided.
A natural vegetative buffer is one of the
more effective and economical methods of re-
moving sediment from overland flow.
113
-------
1. Contour stripping is a method borrowed from
a. the farmer. b. the contractor.
c. nature. d. the foreman.
answer (s)
2. The use of a vegetative buffer near the base of
a highway slope serves tha same function as
a. the storm drain.
b. the top of cut.
c. the interceptor dike.
d. the contour strips.
answer(s)
3. The sod inlet filter
a. should only be used to handle light concen-
trations of sediment.
b. is made up of pads of sod.
c. is best used after firal grading is complete,
d. all of the above.
e . none of the above.
answer(s)
114
-------
QUESTIONS 4
Fill in the blanks
1. S p_ are employed on
construction sites to trap sediment.
2. The filter is used at
storm drains.
3. The gravel inlet filter is h r
to erosion.
4. The configuration of the filter will depend upon
the t of i being protected.
5. Using an i dike with a gravel inlet
filter i trapping efficiency.
115
-------
True or False
1. The sandbag sediment trap is a quick and
economical method of temporarily disrup-
ting flow and trapping the coarser sedi-
ment particles.
_2. Piping is a major cause of failure of many
temporary sediment traps.
3. Straw bale sediment traps last indefinitely,
_4. Close inspection is not required of a straw
bale perimeter barrier.
_5. The function of an excavated sediment trap
is to temporarily detain the runoff.
6. The most effective structures for trapping
sediment are straw bale barriers.
116
-------
Multiplr
1. A dry sediment basin is
a. designed to only temporarily impound runoff
b. drained by a metal riser pipe.
c. requires a formal design.
d. all of the above.
e. only a and c.
answer(s)
2. The vertical distance between the top of the dam and
the crest of the spillway is known as the
a. sediment valve.
b. freeboard.
c. safety factor.
d. ruler.
answer(s)
3. The odd looking device at the top of the riser pipe
is called
a. a barrel.
b. an antivortex plate ind trash rack.
c. an emergency spillway.
d. none of the above.
answer(s)
117
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1. Erosion control r the amount of runoff
that will be generated.
2. Sediment control is the s line of defense.
3. The three factors upon which the amount of sediment
removed from the runoff is dependent are:
a. S that the water flows through the
b. L of time the water was d
c. S and w of the sediment
particles carried into the trap.
4. Leaving a v b at the base of
a steep slope is an effective means of trapping
5. P a natural buffer is one of the
more effective and economical methods of removing
sediment from overland flow.
6. The ability o<£ a graded buffer area to trap sediment
is improved by adding v
7. The Last vegetative filter is
8. Woodland areas should be used only to filter
o flow.
9. C _ s is a method
borrowed from the farmer.
10. It is used to break the f of r
on long hillsides.
118
-------
11. The use of a v b near the
base of a highway slope serves the same function
as strips.
12. G b are employed on
construction sites to retain or trap sediment.
13. The sod inlet filter should be used to handle
1 concentrations of sediment.
14. The g i filter is highly
resistant to erosion.
15. The configuration of the filter will depend upon
the t of i being protected,
16. The interceptor dike is used on r_
rights of way-
17. Straw b and s traps are
quick and economical methods of temporarily dis-
rupting flow.
18. P is a major cause of the failure
of many temporary sediment traps.
19. Piping failure is reduced in temporary sediment
t by placing either the s
traps or s b traps a minimum
of ' "inches in the' ground.
20. A straw bale perimeter barrier is used to provide
a s barrier along the downhill peri-
meter of small graded sites, where area restric-
tions or other factors prevent the use of other
practices.
21. An e sediment trap c
1 to construct.
119
-------
22. S b are the most effec-
tive structures for trapping sediment.
23.
23. A dry sediment basin is designed to only t
impound r during rainfalls.
24. A dry sediment basin is drained by using a standard
metal r p with p
which allow the water to be released at a controlled
rate.
25. Both wet and dry sediment ponds must be
a. vegetatively stabilized.
b. emptied.
c. washed.
d. none of the above.
answer(s)
120
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APPENDIX E
SAMPLE AUDIOVISUAL SUPERVISOR'S MANUAL
121
-------
CONTROL. OF SEDIMENT
GENERATED ON
CONSTRUCTION SITES
SUPERVISOR'S MANUAL
To be used in conjunction
with the audio-visual program.
122
-------
ACKNOWLEDGEMENT
Acknowledgement is hereby made that this material was pre-
pared under the assistance of a jointly sponsored Grant program
by the U.S. Environmental Protection Agency and the State of
Maryland.
123
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CONTROL OF SEDIMENT GENERATED
ON CONSTRUCTION SITES
PURPOSE
The purpose of the Instructor's Manual is to help you
make the best use of the Audiscan filmstrip and work-
book for the self-instructional audiovisual lesson on
Control of Sediment Generated on Construction Sites.
OBJECTIVE
The objective of this instructional package is to pro-
mote better understanding among erosion and sediment
control specialists as to:
- the kinds of sediment control structures and
their functions.
- the importance of proper construction and reg-
ular maintenance of sediment control structures,
PREPARATION FOR PRESENTATION
This instructional package is designed both for self-
study and for group presentation. For an effective
smooth-running group presentation, plan well in ad-
vance. Have the Audiscan projector, the screen and
seating set up. Have the workbooks ready for distrib-
ution.
Before presenting the filmstrip, preview it and read
the workbook so that you can have their contents clear
in your mind and can answer questions. Previewing the
filmstrip also assures you that the Audiscan projector
is working properly.
Finally, prepare the audience. Explain the objectives
of the instructional package. Describe the sequence
of events of the presentation. Tell them that there
will be a short review at the end of the program to
help them discover how well they have understood the
filmstrip.
124
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PRESENTATION
The filmstrip can be viewed continuously. However, be-
cause of the quantity and detail of the information pre-
sented, it is suggested that you view it in sections.
The Audiscan projector will automatically stop at review
points. These automatic stops are built-in for question-
and-answer periods. Always make:~sure everyone under-
stands each part of the filmstrip before going on to the
next part. The Audiscan projector will have to be re-
started manually after- each stop.
PROJECTOR OPERATION
To operate the Audiscan audiovisual projector insert the
appropriate cartridge with the arrow up into the side of
the machine. Turn the machine^on* using..the Volume On/
Off control. To start the program, "press the Start
switch. Focus as desired. To restart the projector,
after it has stopped for review questions, push the
start portion of the Program Hold/Start switch. Should
the audio and visual portions of the filmstrip become
unsynchronized for any reason, synchronization may be
re-established by holding the Lock switch to the left
and at the same time depressing either the Film Hold or
Film Advance switch as appropriate.
SEQUENCE OF EVENTS
Welcome the group and prep.are them as previously desr
cribed. Tell them that a workbook will be distributed,
Add that it was prepared to expand the information in
the filmstrips. Also, inform them of the built-in re-
view periods.
Show Part I of the program Control of Sediment Generat-
ed on Construction Sites. Review the basic functions
of sediment traps. Be sure the trainees are familiar
with the vegetative sediment control practices.
Show Part II. Stress the importance of maintenance
for all sediment control structures. Make sure the
trainees understand the important construction criter-
ia for sediment basins.
125
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IDEAS FOR DISCUSSION
1. What do we mean by "control of sediment
generated on construction sites"?
2. Why can we only expect reasonable ero-
sion control?
3. How do we keep sediment from damaging
the environment?
4. Why must both defenses be used?
5. Why is good planning important in the
preserving of a buffer area?
6. How is the ability of a buffer to trap
sediment improved?
7. Explain the use of contour strips.
8. Why must care be exercised in utilizing
woodland areas for trapping sediment?
9. Discuss the use of grass and legumes as
filters.
10. Discuss the construction of the sod in-
let filter.
11. Discuss the construction of the gravel
inlet filter.
12. Why is maintenance so important?
13. How is the possibility of piping reduced
on temporary sediment traps?
14. How is a straw bale perimeter barrier
used?
15. How can the life of a straw bale sedi-
ment trap be prolonged?
16. How important is maintenance with tem-
porary sediment traps?
126
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17. Describe some ways sediment basins are
cleaned.
18. What is the importance of consulting
local and state regulations before con-
structing a sediment basin?
19. What is a common cause of the failure
of dry temporary sediment basins?
20. Why is the maintenance of a sediment
basin so important?
127
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Control of Sediment Generated
on Construction Sites
WORKBOOK - ANSWERS
Questions 1
1. Erosion Control,
reduces
2. Sediment Control
3. water
4. sediment
Speed, trap
Length, detained
Size, weight
Questions 4
1. Structural practices
2. gravel inlet
3. highly resistent
4. type, inlet
5. interceptor, increases
Questions 2
Questions 5
1.
2.
3.
4.
5.
b
b
a
d
d
1.
2.
3.
4.
5.
6.
True
True
False
False
True
False
Questions 3
1.
2.
3.
4.
5.
6.
True
False
True
True
True
True
Questions 6
1.
2.
3.
4.
d
b
b
d
128
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Questions 7
1. reduces
2. second
3.
a. Speed, trap
b. Length, detained
c. Size, weight
4. vegetative buffer,
sediment
5. Preserving
6. vegetation
7. grass
8. overland
9. Contour stripping
10. flow, runoff
11. vegetated buffers,
contour
12. graded, buffers
13. light
14. gravel inlet
15. type, inlet
16. roadway
rights of way
17. bale, sandbag
18. Piping
19. traps, sandbag,
straw bale, six
20. sediment
21. excavated, cost
little
22. Sediment basins
23. temporarily,
runoff
24. riser pipe,
perforations
25. a
129
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APPENDIX F
PARTICIPANT PROFILE FORM
130
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No. _
PARTICIPANT PROFILE
1. Where were you brought up (lived most of your life) before you were
18?
a. On a farm or ranch (~~)
b. In the country, but not living on a farm or ranch
c. In a town (population under 10,000)
d. In a city
2. How many years of schooling have you completed (please circle the
highest level(s) you have finished)?:
High School Trade School or Military College
_ Service School _
1234 1234 1234
If you attended trade school, what was your major subject?:
If you attended college, what was your major subject?:
3. Please list any other formal courses or classes you have attended
which are related in any way to the general subject of erosion and
sediment control:
4. What is your occupation?:
a. Foreman
b. Inspector ||
How many years have you been engaged in activities related to con-
struction and7or inspection? _^
131
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5. What is your age?:
a. 20-29 D d- 5°-59 D
b. 30-39 D e. over 60 Q
c. 40-49 Q
6. What is your present yearly income from all sources?:
a. Less than 5, 000 Q
b. 5, 000 to 9,999 [J
c. 10, 000 to 14, 999
d. 15, 000 to 19,999
e. Greater than 20, 000
7. What are your main interests and activities outside your job?:
What clubs, groups, or civic organizations do you or have you
belonged to ?:
132
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APPENDIX C
EVALUATION QUESTIONS
133
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EVALUATION QUESTIONS
Based on
EROSION AND SEDIMENTATION
and
THE GOAL, OBJECTIVES AND PRINCIPLES
OF EROSION AND SEDIMENT CONTROL
134
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lnAtiu.cti.oiu : 1. Ttll In blank* whe.ie. lndtcate.d
1. Ctftdle. e-4.the.ti tine, on faal.t>e. at
the. end ofi t>tate.me.nt&
3. In multiple, cno-cce que.£ t-io nt>
place, the. latte.fi on. le.tte.ni> ^on.
the. casut&ct ant>we.n on the. l-ine.
-------
6. Slope steepness, surface roughness, and the amount and
intensity of rainfall are factors that control the
a. amount of rain in a watershed
b. speed at which runoff flows down a slope
c. speed at which rills turn to sheet erosion
7. The destruction of natural v _ and the re-
shaping of the ground s _ are contributing
factors to erosion in urbanizing areas.
8. Stream gaging is a method of determining the amount of
flow in a given waterway.
9 . The principle factors contributing to the acceleration
of erosion in urbanizing areas are:
a. destruction of natural vegetation
b. reshaping of ground surface
c. exposure of subsoils
d. reduced runoff
e. placement of impervious features on the soil
like paving and buildings..
10. In controlling erosion and sedimentation the office
planners are more important than the on-the-ground
field personnel.
11. Sediment pollution damages the quality of water and the
habitat through which the water flows.
-,,,,
136
-------
12. Slope steepness is often expressed as p_ by
engineers and planners.
13. To establish a sediment control program we need:
a. Careful study and planning
b. Cooperation and involvement
c. To pave as much of the construction area as
possible
d. Flexibility
14. Natural or g_ erosion is a relatively slow
process, continually taking place.
15. Erosion resulting from man's activities is termed
a erosion.
16. Practices used to control erosion are:
a. special grading, such as surface roughening
b. constructing long slopes
c. constructing diversion structures
d. clearing all trees off the area
e. using a straw mulch
17. When working on a construction project both contractors
and government officials must cooperate and have over-
all flexibility in applying plans.
T/iue
137
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18. The presense of organic material in a soil has no effect
on a soil's credibility.
19. Generally, erosion is more severe at the base of a short
steep slope than at the base of a long steep slope.
20. While being transported, sediment is divided into two
types: s _ sediment and bedload sediment.
21. The plans developed for a site must be adhered to re-
gardless of problems which develop when work is started
22. A slope which changes 10 feet vertically in 100 feet of
horizontal distance is referred to as a _ percent
slope .
23. In a stream the b _ sediment is made up of
larger and heavier weight particles.
24. A damaging aspect of wind erosion in urbanizing areas
is the collection of dust on structures such as build-
ings and roadways.
T/iae FatA e
25. Erosion due to agriculture is generally (molt/ l }
severe than erosion from urbanizing areas.
138
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26. The removal of a fairly uniform layer of soil from the
land surface is known as s _ erosion.
27. Sediment is undesirable because:
a. it damages water resources
b. it increases the flow in streams
c. it fills the channels so ships can't use the rivers
d. it kills fish and other aquatic life
28. When the depth of the grooves on a soil slope exceeds
four inches the erosion is usually termed _
erosion.
29. Which of the following factors influence erosion:
a. amount of rainfall
b. intensity of rainfall
c . temperature
d, frequency of rainfall
30. Overland erosion occurs on denuded slopes as a result
of rainsplash and runoff.
31. Wind erosion is usually the largest source of sediment
during construction operations.
32, The process by which soils or other surface materials
are transported or deposited by the action of wind,
water, ice or gravity is s _ .
139
-------
33. To achieve effective and reasonable control over erosion
and sediment caused by man's activities using the best
practical combination of procedures, practices and peo-
ple is the goal of erosion and sediment control.
T-tue. Fa£-4 e.
34. Accelerated erosion in stream channels is brought on by
increased r _ from developing areas and the
removal or destruction of natural v _
along stream banks.
35. The best way to protect the land is to control erosion
at its source.
36. From a cextural standpoint, soils having large amounts
of silt and fine sand, as well as those containing
highly expansive clay minerals, are most susceptible to
erosion from rain splash and runoff.
37 . A w _ is any natural or artificial drainage-
way in which waters flow in a definite direction or course
either continuously or intermittently.
38. A formula used to measure erosion is the Universal Soil
_ Equation.
140
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39. Normal tillage of the soil will obliterate rill erosion.
Tiue. FatAn
40. Normal tillage of the soil will obliterate gully erosion,
Tiue. Fa£-4e
41. The longer rain falls on a given area the more runoff
42. Soil loss is expressed as tons per _ per year.
43. A good erosion control practice is to break a long slope
into a series of short slopes.
44. Stream channel erosion includes both stream-
and streambank erosion.
141
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45. The five (5) principles of erosion and sediment control
are:
a. Apply sediment control practices as a peri-
meter protection to prevent off-site damage.
b. Expose the smallest practical area of land
for the shortest possible time.
c. Implement a thorough .maintenance and follow-
up operation.
d. Apply erosion control practices as a peri-
meter protection.
e. Apply soil erosion control practices as a
first line of defense against on-site damage.
f. Apply sediment control practices as a first
line of defense against on-site damage.
g. Plan the development to fit the particular
topography, soils, waterways and natural
vegetation at a site.
h. Expose the minimum area of land for the long-
est time.
142
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46. Which of the following are Objectives of Erosion and
Sediment Control?
a. Establish and maintain a sediment control program,
b. Protect vital land resources from erosion.
c. Protect vital water resources and wildlife from
sediment pollution.
d. Provide high quality water for human use.
47. The development of small grooves on a soil slope is
termed ero s ion.
143
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APPENDIX H
EVALUATION OF PRESENTATION FORM
-------
EVALUATION OF PRESENTATION
1- You have experienced an illustrated lecture and an
audiovisual presentation on some aspects of erosion
control during construction. In the space below,
please write what you liked about each style of
presentation. Also we are interested in your feel-
ing about the style of presentation, not your feel-
ing about the subject of the presentation.
1)
2)
3)
LECTURE
AUDIOVISUAL
1)
2)
3)
145
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Now please tell us what you did not like
about each style of presentation.
LECTURE
AUDIOVISUAL
1)
2)
3)
1)
2)
3)
Would you like to go through the same subject again
in the audiovisual program?
Ve.A to
Would you like to sit through exactly the same
lecture again?
ye.4 to
Do you think that all points discussed in the
audiovisual program were suitably illustrated?
If you checked to what additional illustrations would
you like to see?
146
-------
5. Could you clearly understand the narrator in the
Audiovisual program?
Mo
6. Could you clearly understand the lecturer?
Wo
7. Which presentation do you think you learned the
most from?
Why?
8. If you were given a series of programs to study
which of the following methods would you prefer:
a. Live lecture
b. Audiovisual in a group situation
c. Audiovisual -- take programs by yourself
9. Please explain why you selected the method you
indicated.
10. Did you find the questions in the workbook with
the audiovisual program were a help in learning?
No
147
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11. Did you have sufficient time to answer the questions
in the workbook?
12. What was your opinion of the illustrations (cartoons)
in the audiovisual program (you may check as many as
you wish) :
a. An amusing break
b. Conveyed a real message
c. A frivolous distraction
d. I found it hard to understand the meaning
of some of the drawings
e. I would have liked more of them
f. Other
13. Were the photographs in the audiovisual presentation
clear and understandable?
14. Please make any additional comments:
148
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-660/2-74-071
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Programmed Demonstration for Erosion and Sediment
Control Specialists
5. REPORT DATE February 1974
(date of approval)
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Thomas R. :-lills ; Michael A. Uawrocki; Gregg R. Squire;
Homer T. Hopkins; .lichael L. Clar
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Itittman Associates, Inc.
Environmental & Geosciences Department
9190 Red Branch Road
Columbia, Maryland 21045
10. PROGRAM ELEMENT NO.
1B2042
11. CONTRACT/GRANT NO.
S800854
(15030 FHZ)
12. SPONSORING AGENCY NAME AND ADDRESS
Office of Research and Development
U.S. Environmental Protection Agency
Washington, D.C. 20460
and
13. TYPE OF RE PORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
Water Resources Administration, State of rlarylanc
Annapolis Maryland ?1Am L
15. SUPPLEMENTARY NOTES
Prepared in cooperation with:
Water Resources Administration
State of Maryland
Annapolis, Maryland
16. ABSTRACT
A series of technical presentations and a certification plan for erosion and sediment
control specialists are presented. Fifteen conventional presentations, complete
with visual aids and student handouts, and six audiovisual programs consisting of
film strips, taped narration, work books, and instructor's manuals are described.
Samples of the presentation materials, designed to provide an effective program for
qualifying construction personnel and other persons to pass the certification exam,
are included in appendices. Presentations include such topics as: Goal, Objectives
and Principles of Erosion and Sediment Control; Erosion and Sedimentation; Control
of Sediment Generated on Construction Sites; Control of Runoff During Construction;
Vegetative Soil Stabilization; and Foreman-Inspector Responsibilities. Results of
a demonstration t;o evaluate the conventional presentation approach versus the
audiovisual approach are given. Also described is the development of a plan for
the certification of on-site erosion and sediment control specialists.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Erosion Control
Education
bediment Control
Certification Plan
Construction Related
Erosion
Technical Presentations
Maryland
05 I
13 B
18. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (This Report)'
21. NO. OF PAGES
153
2O. SECURITY CLASS (This page)
22. PRICE
EPA Form 2220-1 (9-73)
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