PB-212 590
The Use of Bags for Solid
Waste Storage and Collection
Stone and Company, Inc.
prepared for
Environmental Protection Agency
1972
Distributed By:
National Technical Information Service
U. S. DEPARTMENT OF COMMERCE
5285 Port Royal Road, Springfield Va. 22151
-------
BIBLIOGRAPHIC DATA
SHEET
4. Tide and Subtitle
1. Report No.
EPA-SW-42D-72
The Use of Bags for So]id Waste Storage and Collection
212 590
1972
6.
7. Author(s)
Ralph Stone and Company. Inc.. Engineers
8' Performing Organization Kept
No.
9. Performing Organization Name and Address
City of Inglewood
105 East Queen Street
Inglewood, California 90301
10. Pro|cct/Task/Work Unit No.
11- fiBBKHKt/Grant No.
G06-EC-00172
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
Office of Solid Waste Managemnt Programs
Washington, D. C. 20460
13. Type of Report & Period
Covered
Final
14.
IS. Supplementary Notes
16. Abstracts The study was conducted to evaluate the suitability of disposable plastic and
paper sack materials for use as solid waste containers. Six residential areas in Ingle-
wood, California, were selected; three were to receive bags for test use and the re-
mainder to serve as a control. Bag systems studied included household polyethylene and
paper bags on holders, free-standing paper bags and polyethylene can liners as well as
large polyethylene commercial bin liners that were distributed to a number of restaurant
in the city. Results were obtained by using time and motion studies and this informatio
was reinforced by laboratory testing and by an aggressive questionnaire program. A mode
of the collection system was then developed and subsequent simulation studies were em-
ployed for cost analysis. The project demonstrated that bags are quite satisfactory as
solid waste container replacements for cans. Sanitation, collection system productivity
and efficiency, and neighborhood appearance were improved and the participants indicated
positive acceptance of the bags. The most prominent problems, however, were the diffi-
culties in developing efficient bulk storage and distribution methods of the bags.
17. Key Words and Document Analysis. 17o. Descriptor-;
*Refuse disposal, *Collection, *Storage, *Containers, Bag papers, Polyethylene (bags),
Time studies, Motion studies, Performance evaluation, Productivity, Efficiency,
Operating costs, Sanitation, Questionnaires, Acceptance
17b. Mcmif icrs/Open-Ended Terms
*Solid waste management, Inglewood (California)
17e. COSA'll l;ie Id/Group
18. Availability Statement
Release to public
FORM NTIS-38 (10-70)
19. Security Class (This
Report)
UNCLASSIFIED
LA£
Cli
20. Security Class (This
Pago
UNCLASSIFIED
21. No. of Pages
297
22. Price
USCOMM-OC 4032'
(L
-------
EPA-SW-42D-72
THE USE OF BAGS FOR SOLID WASTE STORAGE AND COLLECTION
This final report (SW-42d) on work performed under
solid Haste management demonstration grant no. G06-EC-00172
to the City of Inglewood, California, was written by
RALPH STONE AND COMPANY, INC., ENGINEERS
and is reproduced as received from the grantee.
U.S. ENVIRONMENTAL PROTECTION AGENCY
1972
-------
This report has been reviewed by the U.S. Environmental Protection
Agency and approved for publication. Approval does not signify
that the contents necessarily reflect the views and policies of the
U.S. Environmental Protection Agency nor does mention of commercial
products constitute endorsement or recommendation for use by the
U.S. Government.
I I".
-------
ACKNOWLEDGMENTS
We wish to express our appreciation to the representatives of the Public Health
Service's Bureau of Solid Waste Management*for their guidance and assistance during the
conduct of this demonstration. In particular, we wish to thank Dr. Anton Muhich, Former
Director of Demonstration Activities; Mr. Charles Orr, Senior Project Officer; and
Mr. Peter T. Me Garry, Project Officer, for their assistance during the study.
We should also like to take this opportunity to thank representatives from the
City of Inglewood for their outstanding work efforts in ensuring the success of the
demonstration program. Mr. William Farnam, City Engineer and Public Works
Director, provided overall program guidance as the Project Director of the
demonstration. Mr. Harry Frisby, Sanitation Superintendent, was largely responsible
for the fine cooperation exhibited by the refuse collection crews and the residents
of the demonstration area, and provided the driving force necessary to ensure success
of the field demonstration program.
Our appreciation to the bag manufacturing companies and their representatives
and to the cities providing background information on their experiences with bags is
gratefully acknowledged.
*Now the Office of Solid Waste Management Programs, U.S. Environmental
Protection Agency.
-------
ABSTRACT
A two-year demonstration study of bags for use as solid waste containers was
performed In the City of Inglewood, California. Bag systems studied included
household polyethylene and paper bags on holders, free-standing paper bags and
polyethylene can liners as well as large polyethylene commercial bin liners. A
nationwide municipal questionnaire survey of bag use completed by the project engineer
is also included in this report.
Three residential areas, each consisting of a demonstration bag route and a
conventional can control route, were studied for six months and four householder
questionnaires were distributed. The bag and liner systems were evaluated with
respect to cans end to each other in each area and in a residential condominium.
A bin liner questionnaire was distributed to commercial restaurant establishments.
The local transfer station and sanitary landfill operations were observed and
bag materials tests together with studies on litter, dust, bacteria, flies, accidents,
and noise related to bags and cans as waste containers were made.
A mathematical simulation model and benefit-cost analyses were run to compare
waste collection system operations for bags and cans.
•ir
-------
TABLE OF CONTENTS
Page
SUMMARY
A. Background
B.
C.
D.
E.
F.
G.
H.
CONCLUSIONS
1 . Demonstration Location
2. Objectives
Demonstration Program Procedure
1 . Study Approach
2 . Distribution of Bags to Householders
3. Field Data Collection
Results of Field Studies
1 . Collection System
2. Public Health and Environmental
Considerations
3. Landfill and Transfer Operations
4. Commercial Bin Liners
5. Householders' Preferences
6. Voluntary Bag Use
7. National Survey on Usage of Disposable
Bags in Solid Waste Collection Systems
Bag and Liner Materials Testing
Formulation of Bag Evaluation Criteria
System Simulations for Cost Analysis
Collection System Management Cost Analysis
Implementation of a Bag System for Waste
Collection
RECOMMENDATIONS
XVIII
xviii
xviii
xviii
xviii
xviii
xix
xix
xix
xix
xx
xxi
xxii
xxii
xxii
xxiii
xxiii
xxiv
xxv
xxv
xxvi
xxvii
xxx
-in-
-------
I.
III
IV.
V.
VI.
INTRODUCTION
A. General
B . Objectives
BACKGROUND 1 N BAG USE
A. Paper Bags
B. Polyethylene Bags
C. National Survey on Usage of Disposable Bags
in Solid Waste Collection Systems
AREA DESCRIPTION
A. General
B. Solid Waste Collection
AREA EVALUATION AND DEFINITION
A. Study Methodology
B. Route Information
C. Comparative Analysis
D. Composition of Inglewood Solid Waste
DISTRIBUTION OF BAGS TO HOUSEHOLDERS
A. Specifications for Bag Purchases
B. Bid Analysis
C. Bag Distribution Schedule
D. Allocation Criteria
E . Distribution Method
DEMONSTRATION FIELD STUDIES
A. Collection Operations Studies
1 . Effect of Bags on Collection Time
2. Mean Number of Items and Amount of
Solid Waste per Stop
3. Capacity Utilized in Cans and Bugs
4. Collection Time Comparisons Between
Polyethylene and Paper Bags
5. Condominium Time and Motion Studies
Page
1
1
1
2
2
4
5
7
7
7
9
9
9
10
11
13
13
13
14
14
15
16
16
16
16
17
17
18
•IV
-------
Poge
B. Environmental and Safety Studies 18
1. Noise Survey 18
2. Fly Studies 20
3. Litter Index Studies 21
4. Safety 22
C. Handling and Disposal Operations 23
1. Effects of Polyethylene Bags on Landfill
Procedures 23
2. Polyethylene and Paper Bag Bio-Degradation
Effects 24
3. Effects of Disposable Bags on Transfer Station
Operations 24
4. Effects of Disposable Bags on Packer-Type
Collection Vehicle Waste Density 25
D. Field Demonstration of Liners for Large Containers 25
1. Results of Field Survey 25
2. Results of Bin Liner Questionnaire 25
3. Time and Motion Studies of Bin Line-
Collection 26
4. Bin Liner Cost Evaluation 26
E. Survey of Continued Bag Use 26
VII. PUBLIC HEALTH STUDIES 27
A. Microbiological and Dust Tests 27
1. Parameters 27
a. Waste Collection Activity to be Sampled 27
b. Dust Collection Bacterial Plate Exposure
Time 27
c. Point of Dust Sample Collection 28
d. Number of Dust Samples 28
e. Background Dust Condition 28
2. Field Tests 28
3. Bacteria and Fungi Counts 28
a. Cans 28
b. Bags and Liners 29
•v-
-------
Page
4. Summary of Microbe Counts 30
5. Microbiological Identification 30
a. Bacteria 31
b. Fungi 31
c. Yeasts 32
6. Evaluation 32
B. Laboratory Dust Distribution Study 32
1. Objective 32
2. Facilities and Equipment 32
3. Procedure 33
4. Results 34
VIII. QUESTIONNAIRES 35
A. Distribution of Questionnaires 35
1. Questionnaire 1 (Pretest Questionnaire) 35
2. Questionnaire 2 35
3. Questionnaire 3 35
4. Questionnaire 4 (Briarwood Condominium
Questionnaire) 36
5. Questionnaire 5 (Follow-Up Questionnaire) 36
B. Results of Questionnaire 1 (Pretest Questionnaire) 36
C. Results of Questionnaires 2 and 3 37
1. Improvements 37
2. Difficulties 38
3. Comments 38
4. System Comparisons 38
D. Results of Questionnaire 4 (Briarwood Condominium
Questionnaire) 39
1. Improvements 39
2. Bag System Difficulties 39
3. System Acceptance 40
4. Comments 40
-vi •
-------
E. Results of Questionnaire 5 (FoI low-Up Questionnaire) 40
1. System Comparison 41
2. System Improvements and Difficulties 41
3. Comments 41
IX. BAG AND LINER MATERIALS TESTING 42
A. Objectives 42
B. Tests 42
1. Tensile Stress-Strain 42
2. Cottonseed and Vegetable Oil Soak 44
3. Water, Milk, and Butter Soak 44
4. Temperature Exposure 44
5. Perforation 44
6. Pinhole 44
7. Puncture 45
8. Creep 45
9. Moisture Content and Absorption 46
10. Evaporation 46
11. Odor 46
C. Summary of Test Results 47
X. FORMULATION OF BAG EVALUATION CRITERIA 48
A. Approach 48
B. Materials Properties 48
1. Polyethylene 48
2. Paper 50
C. Criteria for Bag Selection 51
1. Proposed Criterion for Selection of Polyethylene
Bags 51
2. Proposed Criterion for Selection of Paper Bags 52
3. Algorithm Formulation for Total Evaluation of
Bag Suitability 52
4. Bag System Comparisons 53
-vii-
-------
XI.
ECONOMIC ANALYSIS
A.
B.
C.
D.
E.
TABLES
FIGURES
PLATES
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
System Simulations for Cost Analysis
Container System Operating Costs
Householders' Economic Benefits
Collection System Economics
Incentives for Use of Bag Systems
Glossary
Standards for Paper and Polyethylene Bags
Table Bl - Test Requirements: Non- Extensible
Kraft
Table B2 - Test Requirements: Extensible Kraft
1 . Specifications for Bag and Holder Purchases
2. Specification #68-30 for Paper Bags for
Solid Waste
3. Bidder's Proposal for Specification #68-30
4. Specification #68-31 for Plastic Bags for
Solid Waste
5. Bidder's Proposal for Specification #68-31
6. Specification #68-32 for Holders for Solid
Waste Bags
7. Bidder's Proposal for Specification #68-32
List of Prospective Bidders
1 . Questionnaire 1: Pretest
2. Questionnaire 2: Solid Waste Bag Use
3. Questionnaire 3: Solid Waste Bag System
Comparisons
Page
55
55
58
58
59
59
62
151
211
214
216
219
220
221
223
227
228
230
231
232
233
235
236
238
-viii-
-------
BIBLIOGRAPHIC DATA
SHEET
4. Title and Subtitle
1. Report No.
EPA-SW-42D-72
The Use of Bags for Solid Waste Storage and Collection
212 590
1972
6.
7. Authot(s)
Ralph Stone and Company. Inc.
Engineers
&• Performing Organization Kept.
No.
Performing Organization Name and Address
City of Inglewood
105 East Queen Street
Inglewood, California 90301
10. Project/Task/Work Unit No.
11. &WXHOCt /Grant No.
G06-EC-00172
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
Office of Solid Waste Managemnt Programs
Washington, D. C. 20460
13. Type of Report & Period
Covered
Final
14.
15. Supplementary Notes
16. Abstracts xhe study was conducted to evaluate the suitability of disposable plastic and
paper sack materials for use as solid waste containers. Six residential areas in Ingle-
wood, California, were selected; three were to receive bags for test use and the re-
mainder to serve as a control. Bag systems studied included household polyethylene and
paper bags on holders, free-standing paper bags and polyethylene can liners as well as
large polyethylene commercial bin liners that were distributed to a number of restaurant
in the city. Results were obtained by using time and motion studies and this informatio i
was reinforced by laboratory testing and by an aggressive questionnaire program. A mode
of the collection system was then developed and subsequent simulation studies were em-
ployed for cost analysis. The project demonstrated that bags are quite satisfactory as
solid waste container replacements for cans. Sanitation, collection system productivity
and efficiency, and neighborhood appearance were improved and the participants indicated
positive acceptance of the bags. The most prominent problems, however, were the diffi-
culties in developing efficient bulk storage and distribution methods of the bags.
17. Key Words and Document Analysis. 17o. Descriptors
*Refuse disposal, *Collection, *Storage, *Containers, Bag papers, Polyethylene (bags),
Time studies, Motion studies, Performance evaluation, Productivity, Efficiency,
Operating costs, Sanitation, Questionnaires, Acceptance
17b. Idcntif ivrs/Opcn-Ended Terms
*Solid waste management, Inglewood (California)
17c. COSAl I Held/Group
Reproduced by
NATIONAL TECHNICAL
INFORMATION SERVICE
U S Deportment of Commerce
Springfield VA 22151
18. Availability Statement
Release to public
FORM NTIS-33 (IO-70)
19. Security Class (This
Report)
UNCLASSIFIED
20. Security Class (This
Page
UNCLASSIFIED
21. No. of Pages
297
22. Price
USCOMM-DC 4032'
IL
-------
EPA-SW-42D-72
THE USE OF DAGS FOR SOLID WASTE STORAGE AND COLLECTION
This final report (SU-42d) on work performed under
solid waste management demonstration grant no. G06-EC-00172
to the City of Inglewoods California, was written by
RALPH STONE AND COMPANY, INC., ENGINEERS
and is reproduced as received from the grantee.
U.S. ENVIRONMENTAL PROTECTION AGENCY
1972
-------
This report has been reviewed by the U.S. Environmental Protection
Agency and approved for publication. Approval does not signify
that the contents necessarily reflect the views and policies of the
U.S. Environmental Protection Agency nor does mention of conrnercial
products constitute endorsement or recommendation for use by the
U. S. Government.
\r-
-------
ACKNOWLEDGMENTS
We wish to express our appreciation to the representatives of the Public Health
Service's Bureau of Solid Waste Management*for their guidance and assistance during the
conduct of this demonstration. In particular, we wish to thank Dr. Anton Muhich, Former
Director of Demonstration Activities; Mr. Charles Orr, Senior Project Officer; and
Mr. Peter T. Me Garry, Project Officer, for their assistance during the study.
We should also like to take this opportunity to thank representatives from the
City of Inglewood for their outstanding work efforts in ensuring the success of the
demonstration program. Mr. William Famam, City Engineer and Public Works
Director, provided overall program guidance as the Project Director of the
demonstration. Mr. Harry Frisby, Sanitation Superintendent, was largely responsible
for the fine cooperation exhibited by the refuse collection crews and the residents
of the demonstration area, and provided the driving force necessary to ensure success
of the field demonstration program.
Our appreciation to the bag manufacturing companies and their representatives
and to the cities providing background information on their experiences with bags is
gratefully acknowledged.
*Now the Office of Solid Waste Management Programs, U.S. Environmental
Protection Agency.
-------
ABSTRACT
A two-year demonstration study of bags for use as solid waste containers was
performed in the City of Inglewood, California. Bag systems studied included
household polyethylene and paper bags on holders, free-standing paper bags and
polyethylene can liners as well as large polyethylene commercial bin liners. A
nationwide municipal questionnaire survey of bag use completed by the project engineer
is also included in this report.
Three residential areas, each consisting of a demonstration bag route and a
conventional can control route, were studied for six months and four householder
questionnaires were distributed. The bag and liner systems were evaluated with
respect to cans end to each other in each area and in a residential condominium.
A bin liner questionnaire was distributed to commercial restaurant establishments.
The local transfer station and sanitary landfill operations were observed and
bag materials tests together with studies on litter, dust, bacteria, flies, accidents,
and noise related to bags and cans as waste containers were made.
A mathematical simulation model and benefit-cost analyses were run to compare
waste collection system operations for bags and cans.
-ii-
-------
TABLE OF CONTENTS
Page
SUMMARY
A. Background
B.
C.
D.
E.
F.
G.
H.
CONCLUSIONS
1 . Demonstration Location
2. Objectives
Demonstration Program Procedure
1 . Study Approach
2. Distribution of Bags to Householders
3. Field Data Collection
Results of Field Studies
1 . Collection System
2. Public Health and Environmental
Considerations
3. Landfill and Transfer Operations
4. Commercial Bin Liners
5. Householders' Preferences
6. Voluntary Bag Use
7. National Survey on Usage of Disposable
Bags in Solid Waste Collection Systems
Bag and Liner Materials Testing
Formulation of Bag Evaluation Criteria
System Simulations for Cost Analysis
Collection System Management Cost Analysis
Implementation of a Bag System for Waste
Collection
RECOMMENDATIONS
XVIII
• • •
XVIII
xviii
xviii
xviii
xviii
xix
xix
xix
xix
xx
xx i
xxii
xxii
xxii
xxiii
xxiii
xxiv
xxv
xxv
xxvi
xxvii
xxx
-in-
-------
Poge
I. INTRODUCTION 1
A. General 1
B. Objectives 1
11. BACKGROUND IN BAG USE 2
A. Paper Bags 2
B. Polyethylene Bags 4
C. National Survey on Usage of Disposable Bags
in Solid Waste Collection Systems 5
III. AREA DESCRIPTION 7
A. General 7
B. Solid Waste Collection 7
IV. AREA EVALUATION AND DEFINITION 9
A. Study Methodology 9
B. Route Information 9
C. Comparative Analysis 10
D. Composition of Inglewood Solid Waste 11
V. DISTRIBUTION OF BAGS TO HOUSEHOLDERS 13
A. Specifications for Bag Purchases 13
B. Bid Analysis 13
C. Bag Distribution Schedule 14
D. Allocation Criteria 14
E. Distribution Method 15
VI. DEMONSTRATION FIELD STUDIES 16
A. Collection Operations Studies 16
1 . Effect of Bags on Collection Time 16
2. Mean Number of Items and Amount of
Solid Waste per Stop 16
3. Capacity Utilized in Cans and Bags 17
4. Collection Time Comparisons Between
Polyethylene and Paper Bags 17
5. Condominium Time and Motion Studies 18
•iv
-------
Poge
B. Environmental and Safety Studies 18
1. Noise Survey 18
2. Fly Studies 20
3. Litter Index Studies 21
4. Safety 22
C. Handling and Disposal Operations 23
1. Effects of Polyethylene Bags on Landfill
Procedures 23
2. Polyethylene and Paper Bag Bio-Degradation
Effects 24
3. Effects of Disposable Bags on Transfer Station
Operations 24
4. Effects of Disposable Bags on Packer-Type
Collection Vehicle Waste Density 25
D. Field Demonstration of Liners for Large Containers 25
1. Results of Field Survey 25
2. Results of Bin Liner Questionnaire 25
3. Time and Motion Studies of Bin Liner
Collection 26
4. Bin Liner Cost Evaluation 26
E. Survey of Continued Bag Use 26
VII. PUBLIC HEALTH STUDIES 27
A. Microbiological and Dust Tests 27
1. Parameters 27
a. Waste Collection Activity to be Sampled 27
b. Dust Collection Bacterial Plate Exposure
Time 27
c. Point of Dust Sample Collection 28
d. Number of Dust Samples 28
e. Background Dust Condition 28
2. Field Tests 28
3. Bacteria and Fungi Counts 28
a. Cans 28
b. Bags and Liners 29
•v-
-------
Page
4. Summary of Microbe Counts 30
5. Microbiological Identification 30
a. Bacteria 31
b. Fungi 31
c. Yeasts 32
6. Evaluation 32
B. Laboratory Dust Distribution Study 32
1. Objective 32
2. Facilities and Equipment 32
3. Procedure 33
4. Results 34
VIII. QUESTIONNAIRES 35
A. Distribution of Questionnaires 35
1. Questionnaire 1 (Pretest Questionnaire) 35
2. Questionnaire 2 35
3. Questionnaire 3 35
4. Questionnaire 4 (Briarwood Condominium
Questionnaire) 36
5. Questionnaire 5 (Fo I low-Up Questionnaire) 36
B. Results of Questionnaire 1 (Pretest Questionnaire) 36
C. Results of Questionnaires 2 and 3 37
1. Improvements 37
2. Difficulties 38
3. Comments 38
4. System Comparisons 38
D. Results of Questionnaire 4 (Briarwood Condominium
Questionnaire) 39
1. Improvements 39
2. Bag System Difficulties 39
3. System Acceptance 40
4. Comments 40
-VI'
-------
Page
E. Results of Questionnaire 5 (Follow-Up Questionnaire) 40
1. System Comparison 41
2. System Improvements and Difficulties 41
3. Comments 41
IX. BAG AND LINER MATERIALS TESTING 42
A. Objectives 42
B. Tests 42
1. Tensile Stress-Strain 42
2. Cottonseed and Vegetable Oil Soak 44
3. Water, Milk, and Butter Soak 44
4. Temperature Exposure 44
5. Perforation 44
6. Pinhole 44
7. Puncture 45
8. Creep 45
9. Moisture Content and Absorption 46
10. Evaporation 46
11. Odor 46
C. Summary of Test Results 47
X. FORMULATION OF BAG EVALUATION CRITERIA 48
A. Approach 48
B. Materials Properties 48
1. Polyethylene 48
2. Paper 50
C. Criteria for Bag Selection 51
1. Proposed Criterion for Selection of Polyethylene
Bags 51
2. Proposed Criterion for Selection of Paper Bags 52
3. Algorithm Formulation for Total Evaluation of
Bag Suitability 52
4. Bag System Comparisons 53
-vii-
-------
XI.
ECONOMIC ANALYSIS
A.
B.
C.
D.
E.
TABLES
FIGURES
PLATES
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
System Simulations for Cost Analysis
Container System Operating Costs
Householders' Economic Benefits
Collection System Economics
Incentives for Use of Bag Systems
Glossary
Standards for Paper and Polyethylene Bags
Table Bl - Test Requirements: Non- Extensible
Kraft
Table B2 - Test Requirements: Extensible Kraft
1 . Specifications for Bag and Holder Purchases
2. Specification *68-30 for Paper Bags for
Solid Waste
3. Bidder's Proposal for Specification #68-30
4. Specification #68-31 for Plastic Bags for
Solid Waste
5. Bidder's Proposal for Specification #68-31
6. Specification #68-32 for Holders for Solid
Waste Bags
7. Bidder's Proposal for Specification #68-32
List of Prospective Bidders
1 . Questionnaire 1: Pretest
2. Questionnaire 2: Solid Waste Bag Use
3. Questionnaire 3: Solid Waste Bag System
Comparisons
Page
55
55
58
58
59
59
62
151
211
214
216
219
220
221
223
227
228
230
231
232
233
235
236
238
-VIII-
-------
BIBLIOGRAPHIC DATA
SHEET
4. Title and Subt itle
1. Report No.
EPA-SW-42D-72
The Use of Bags for Solid Waste Storage and Collection
212 590
1972
6.
7. Author(s)
Ralph Stone and Company. Inc. . Engineers
&• Performing Organization Kept.
No.
9. Performing Organization Name and Address
City of Inglewood
105 East Queen Street
Inglewood, California 90301
10. Project/Task/Work Unit No.
11- KmCHXt/Grant No.
G06-EC-00172
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
Office of Solid Waste Managemnt Programs
Washington, D. C. 20460
13. Type of Report & Period
Covered
Final
14.
IS. Supplementary Notes
16. Abstracts xhe study was conducted to evaluate the suitability of disposable plastic and
paper sack materials for use as solid waste containers. Six residential areas in Ingle-
wood, California, were selected; three were to receive bags for test use and the re-
mainder to serve as a control. Bag systems studied included household polyethylene and
paper bags on holders, free-standing paper bags and polyethylene can liners as well as
large polyethylene commercial bin liners that were distributed to a number of restaurant
in the city. Results were obtained by using time and motion studies and this informatio
was reinforced by laboratory testing and by an aggressive questionnaire program. A mode
of the collection system was then developed and subsequent simulation studies were em-
ployed for cost analysis. The project demonstrated that bags are quite satisfactory as
solid waste container replacements for cans. Sanitation, collection system productivity
and efficiency, and neighborhood appearance were improved and the participants indicated
positive acceptance of the bags. The most prominent problems, however, were the diffi-
culties in developing efficient bulk storage and distribution methods of the bags.
17. Key Words and Document Analysis. 17o. Descriptors
*Refuse disposal, *Collection, *Storage, Containers, Bag papers, Polyethylene (bags),
Time studies, Motion studies, Performance evaluation, Productivity, Efficiency,
Operating costs, Sanitation, Questionnaires, Acceptance
17b. Identificrs/Opcn-Ended Terms
*Solid waste management, Inglewood (California)
17e. COSAll Kield/Group
Reproduced by
NATIONAL TECHNICAL
INFORMATION SERVICE
U S Deportment of Commerce
Springfield VA 22131
18. Availability Statement
Release to public
19. Security Class (This
Report)
UNCLASS1F1I
LASS1F1ED
Class (Thi!
20. Security Class (This
Page
UNCLASSIFIED
21. No. of Pages
297
22. Price
FORM NTIS-35 (10-70)
USCOMM-DC 4032!
IL
-------
EPA-SW-42D-72
THE USE OF BAGS FOR SOLID WASTE STORAGE AND COLLECTION
This final report (SW-42d) on work performed under
solid waste management demonstration grant no. G06-EC-00172
to the City of Inglewood, California, was written by
RALPH STONE AND COMPANY, INC., ENGINEERS
and is reproduced as received from the grantee.
U.S. ENVIRONMENTAL PROTECTION AGENCY
1972
-------
This report has been reviewed by the U.S. Environmental Protection
Agency and approved for publication. Approval does not signify
that the contents necessarily reflect the views and policies of the
U.S. Environmental Protection Agency nor does mention of commercial
products constitute endorsement or recommendation for use by the
U. S. Government.
-------
ACKNOWLEDGMENTS
We wish to express our appreciation to the representatives of the Public Health
Service's Bureau of Solid Waste Management*for their guidance and assistance during the
conduct of this demonstration. In particular, we wish to thank Dr. Anton Muhich, Former
Director of Demonstration Activities; Mr. Charles Orr, Senior Project Officer; and
Mr. Peter T. McGarry, Project Officer, for their assistance during the study.
We should also like to take this opportunity to thank representatives from the
City of Inglewood for their outstanding work efforts in ensuring the success of the
demonstration program. Mr. William Famam, City Engineer and Public Works
Director, provided overall program guidance as the Project Director of the
demonstration. Mr. Harry Frisby, Sanitation Superintendent, was largely responsible
for the fine cooperation exhibited by the refuse collection crews and the residents
of the demonstration area, and provided the driving force necessary to ensure success
of the field demonstration program.
Our appreciation to the bag manufacturing companies and their representatives
and to the cities providing background information on their experiences with bags is
gratefully acknowledged.
*Now the Office of Solid Waste Management Programs, U.S. Environmental
Protection Agency.
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ABSTRACT
A two-year demonstration study of bags for use as solid waste containers was
performed in the City of Inglewood, California. Bag systems studied included
household polyethylene and paper bags on holders, free-standing paper bags and
polyethylene can liners as well as large polyethylene commercial bin liners. A
nationwide municipal questionnaire survey of bag use completed by the project engineer
is also included in this report.
Three residential areas, each consisting of a demonstration bag route and a
conventional can control route, were studied for six months ond four householder
questionnaires were distributed. The bag and liner systems were evaluated with
respect to cans end to each other in each area and in a residential condominium.
A bin liner questionnaire was distributed to commercial restaurant establishments.
The local transfer station and sanitary landfill operations were observed and
bag materials tests together with studies on litter, dust, bacteria, flies, accidents,
and noise related to bags and cans as waste containers were made.
A mathematical simulation model and benefit-cost analyses were run to compare
waste collection system operations for bags and cans.
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TABLE OF CONTENTS
Page
SUMMARY
A. Background
1 . Demonstration Location
2. Objectives
B. Demonstration Program Procedure
1 . Study Approach
2. Distribution of Bags to Householders
3. Field Data Collection
C.
D.
E.
F.
G.
H.
CONCLUSIONS
Results of Field Studies
1 . Collection System
2. Public Health and Environmental
Considerations
3. Landfill and Transfer Operations
4. Commercial Bin Liners
5. Householders' Preferences
6. Voluntary Bag Use
7. National Survey on Usage of Disposable
Bags in Solid Waste Collection Systems
Bag and Liner Materials Testing
Formulation of Bag Evaluation Criteria
System Simulations for Cost Analysis
Collection System Management Cost Analysis
Implementation of a Bag System for Waste
Collection
RECOMMENDATIONS
XVIII
xviii
xviii
xviii
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xix
xix
xix
xix
xx
xxi
xxii
xxii
xxii
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xxiii
xxiv
xxv
xxv
xxvi
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Poge
I. INTRODUCTION 1
A. General ]
B. Objectives 1
II. BACKGROUND IN BAG USE 2
A. Paper Bags 2
B. Polyethylene Bags 4
C. National Survey on Usage of Disposable Bags
in Solid Waste Collection Systems 5
III. AREA DESCRIPTION 7
A. General 7
B. Solid Waste Collection 7
IV. AREA EVALUATION AND DEFINITION 9
A. Study Methodology 9
B. Route Information 9
C. Comparative Analysis 10
D. Composition of Inglewood Solid Waste 11
V. DISTRIBUTION OF BAGS TO HOUSEHOLDERS 13
A. Specifications for Bag Purchases 13
B. Bid Analysis 13
C. Bag Distribution Schedule 14
D. Allocation Criteria 14
E. Distribution Method 15
VI. DEMONSTRATION FIELD STUDIES 16
A. Collection Operations Studies 16
1 . Effect of Bags on Collection Time 16
2. Mean Number of Items and Amount of
Solid Waste per Stop 16
3. Capacity Utilized in Cans and Bugs 17
4. Collection Time Comparisons Between
Polyethylene and Paper Bags 17
5. Condominium Time and Motion Studies 18
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B. Environmental and Safety Studies 18
1. Noise Survey 18
2. Fly Studies 20
3. Litter Index Studies 21
4. Safety 22
C. Handling and Disposal Operations 23
1. Effects of Polyethylene Bags on Landfill
Procedures 23
2. Polyethylene and Paper Bag Bio-Degradation
Effects 24
3. Effects of Disposable Bags on Transfer Station
Operations 24
4. Effects of Disposable Bags on Packer-Type
Collection Vehicle Waste Density 25
D. Field Demonstration of Liners for Large Containers 25
1. Results of Field Survey 25
2. Results of Bin Liner Questionnaire 25
3. Time and Motion Studies of Bin Liner
Collection 26
4. Bin Liner Cost Evaluation ' 26
E. Survey of Continued Bag Use 26
VII. PUBLIC HEALTH STUDIES 27
A. Microbiological and Dust Tests 27
1. Parameters 27
a. Waste Collection Activity to be Sampled 27
b. Dust Collection Bacterial Plate Exposure
Time 27
c. Point of Dust Sample Collection 28
d. Number of Dust Samples 28
e. Background Dust Condition 28
2. Field Tests 28
3. Bacteria and Fungi Counts 28
a. Cans 28
b. Bags and Liners 29
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Page
4. Summary of Microbe Counts 30
5. Microbiological Identification 30
a. Bacteria 31
b. Fungi 31
c. Yeasts 32
6. Evaluation 32
B. Laboratory Dust Distribution Study 32
1. Objective 32
2. Facilities and Equipment 32
3. Procedure 33
4. Results 34
VIII. QUESTIONNAIRES 35
A. Distribution of Questionnaires 35
1. Questionnaire 1 (Pretest Questionnaire) 35
2. Questionnaire 2 35
3. Questionnaire 3 35
4. Questionnaire 4 (Briarwood Condominium
Questionnaire) 36
5. Questionnaire 5 (Follow-Up Questionnaire) 36
B. Results of Questionnaire 1 (Pretest Questionnaire) 36
C. Results of Questionnaires 2 and 3 37
1. Improvements 37
2. Difficulties 38
3. Comments 38
4. System Comparisons 38
D. Results of Questionnaire 4 (Briarwood Condominium
Questionnaire) 39
1. Improvements 39
2. Bag System Difficulties 39
3. System Acceptance 40
4. Comments 40
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E. Results of Questionnaire 5 (Follow-Up Questionnaire) 40
1. System Comparison 41
2. System Improvements and Difficulties 41
3. Comments 41
IX. BAG AND LINER MATERIALS TESTING 42
A. Objectives 42
B. Tests 42
1. Tensile Stress-Strain 42
2. Cottonseed and Vegetable Oil Soak 44
3. Water, Milk, and Butter Soak 44
4. Temperature Exposure 44
5. Perforation 44
6. Pinhole 44
7. Puncture 45
8. Creep 45
9. Moisture Content and Absorption 46
10. Evaporat ion 46
11. Odor 46
C. Summary of Test Results 47
X. FORMULATION OF BAG EVALUATION CRITERIA 48
A. Approach 48
B. Materials Properties 48
1. Polyethylene 48
2. Paper 50
C. Criteria for Bag Selection 51
1. Proposed Criterion for Selection of Polyethylene
Bags 51
2. Proposed Criterion for Selection of Paper Bags 52
3. Algorithm Formulation for Total Evaluation of
Bag Suitability 52
4. Bag System Comparisons 53
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XI.
ECONOMIC ANALYSIS
A,
B.
C.
D.
E.
TABLES
FIGURES
PLATES
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
APPENDIX E
System Simulations for Cost Anal/sis
Container System Operating Costs
Householders' Economic Benefits
Collection System Economics
Incentives for Use of Bag Systems
G lossary
Standards for Paper and Polyethylene Bags
Table Bl - Test Requirements: Non- Extensible
Kraft
Table B2 - Test Requirements: Extensible Kraft
1 . Specifications for Bag and Holder Purchases
2. Specification #68-30 for Paper Bags for
Solid Waste
3. Bidder's Proposal for Specification #68-30
4. Specification #68-31 for Plastic Bags for
Solid Waste
5. Bidder's Proposal for Specification #68-31
6. Specification #68-32 for Holders for Solid
Waste Bags
7. Bidder's Proposal for Specification #68-32
List of Prospective Bidders
1 . Questionnaire 1: Pretest
2. Questionnaire 2: Solid Waste Bag Use
3. Questionnaire 3: Solid Waste Bag System
Comparisons
Page
55
55
58
58
59
59
62
151
211
214
216
219
220
221
223
227
228
230
231
232
233
235
236
238
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APPENDIX F
APPENDIX G
APPENDIX H
APPENDIX I
REFERENCES
Poge
4. Questionnaire 4: Briarwood Condominium -
Solid Waste Bag Use 240
5. Questionnaire 5: Bag System Evaluation 242
6. Landfill Operator Questionnaire 243
7. Nationwide Solid Waste Bag Use Questionnaire 244
8. Bin Liner Questionnaire 246
Laboratory Procedure for Analysis of Microbiological
Dust Tests 247
Bibliography on Dust Studies 248
Response Summary: Questionnaires 2 and 3 249
Table HI - Summary of Responses to Questionnaire 2 250
Table H2 - Summary of Responses to Questionnaire 2
(Expressed in Percentages) 252
Table H3 - Summary of Responses to Questionnaire 3 255
Table H4 - Summary of Responses to Questionnaire 3
(Expressed in Percentages) 257
Mathematical Model Description 260
264
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LIST OF TABLES
Table No. Title Page
1 CIimatological Data 62
2 Operating Statistics, City of Inglewood Collection
Operations 63
3 Study Area Description 64
4 Initial Field Survey, Containers 65
5 Initial Field Survey, Items 66
6 Initial Field Survey, Collection Time (Minutes) 67
7 Initial Field Survey, Travel Time Between Stops (Minutes) 68
8 Initial Field Survey Significance Test - Total Items Per
Stop 69
9 Quantity of Solid Waste Per Household Unit 70
10 Solid Waste Physical Data Sampling 71
11 Purchase Summary 73
12 Collection Time Per Stop 74
13 Average Collection Time Savings Per Stop 75
14 Container Data Summary 76
15 Environmental Survey Summary 77
16 Field Survey, Solid Waste Containers (Number) 78
17 Significance Test - Total Items Per Stop, Area A 79
18 Significance Test - Total Items Per Stop, Area B 80
19 Significance Test - Total Items Per Stop, Area C 81
20 Field Container Weights 82
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Table No. Title Page
21 Field Survey Waste Collection at Briarwood Condominium,
Inglewood, California 83
22 Sound Measurements 85
23 Constants for Use in the Noise Rating Formula 86
24 Noise Rating Numbers - Field Tests 87
25 Noise Rating Numbers - Laboratory Tests 88
26 Frequency Distribution of Number of Larvae Migrating
from Solid Waste Containers 89
27 Frequency Distribution of Number of Weeks More Than
Twenty Larvae Migrated from Solid Waste Containers 90
28 Street Litter Indices 91
29 Litter Index - Bags vs. Cans 93
30 Summary of Responses to Bin Liner Questionnaire 94
31 Summary of Comments to Bin Liner Questionnaire 95
32 Comparison of Bin Collection Time: With and Without 96
33 Polyethylene Bin Liner Cost Analysis 97
34 Can Collection Dust Samples 98
35 Bag Collection Dust Samples 99
36 Plate Counts for Microorganisms from Can Collection
Dust Samples 100
37 Plate Counts for Microorganisms from Bag Collection 101
Dust Samples
38 Number of Colonies Per Plate 102
39 List of Group and Genera of a Few Bacteria Isolated from 103
Test Plates
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Table No. Title Page
40 List of Filamentous Fungi Isolated from Test Plates 104
41 Major Diseases Caused by Yeast-Like Microorganisms 105
42 Questionnaire 2: Responses by Bag System 106
43 Questionnaire 3: Responses by Bag System 107
44 Summary of Responses to Questionnaire 1 (Pre-Test
Questionnaire) 108
45 Combined Summary of Responses to Questionnaires 2 and 3 109
46 Combined Summary of Responses to Questionnaires 2 and 3
(Expressed in Percentages) 111
47 Summary of Comments from Questionnaires 2 and 3 114
48 System Comparisons 116
49 Summary of Responses to Questionnaire 4 (Briarwood
Condominium Questionnaire) 117
50 Summary of Responses to Questionnaire 4 (Briarwood
Condominium Questionnaire) (Expressed In Percentages) 118
51 Summary of Comments from Questionnaire 4 (Briarwood
Condominium Questionnaire) 120
52 Questionnaire 5 (Follow-Up Questionnaire) 121
53 Summary of Comments from Questionnaire 5 (Follow-Up
Q uestionna ire) 123
54 Dimensional Properties of Bag Samples Tested in Laboratory 125
55 Average Failure Loads (Ib) 126
56 Creep Tests on Polyethylene Bags and Liners 129
57 Moisture Absorption 130
58 Moisture Evaporation 131
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Toble No. Title Poge
59 Dimensional Characteristics of Bags and Can Liners
Tested In Field 132
60 Summary of Material and Bag Properties 133
61 Householders' Ratings (a;) for Total Evaluation of Bag
Suitability 134
62 Questionnaire 5, Importance Ratings (Number of Responses) 136
63 Questionnaire 5, Importance Ratings (Expressed as
Percentages of Total Response) 137
64 Weighting Coefficients (bj) for Total Evaluation of Bag
Suitability 138
65 Algorithm Ratings (ajb;) for Total Evaluation of Bag
Suitability
66 Collection Times 141
67 Costs of Vehicle Time - Equipment Cost Only 142
68 Unit Costs of Can and Bag Systems 143
69 Cost Analysis - Cans and Bag Systems - City (Wholesale)
Distribution System 145
70 Cost Analysis - Cans and Bag Systems - Private (Retail)
Purchase System 147
71 Benefit-Cost Evaluation for Householders ($/residence/year) 149
72 Effects of Bags on Collection
Vehicle Waste Densities 150
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LIST OF FIGURES
Figure No. Title Page
1 Location Map, Southern California 151
2 Location Map, Los Angeles Area 152
3 Street Map, Study Area A, Single Family Residential Area 153
4 Street Map, Study Area B, Single Family Residential Area 154
5 Street Map, Study Area C, Single and Multiple Family
Residential Area 155
6 Study Area Locations, Ingle wood, California 156
7 Collection Time, Cans Only - Area A 157
8 Collection Time, Cans Only -Area B 158
9 Collection Time, Cans Only -Area C 159
10 Collection Time, Items-Area A 160
11 Collection Time, Items-Area B 161
12 Collection Time, Items-Area C 162
13 Bag and Liner Distribution, Route A1 163
14 Bag and Liner Distribution, Route B4 164
15 Bag and Liner Distribution, Route C5 165
16 Bag and Liner Distribution Summary, Routes Al, B4, C5 166
17 Collection Time Distribution, Route Al 167
18 Collection Time Distribution, Route A2 168
19 Collection Time, Bags and Cans - Area A 169
20 Collection Time, Bags and Cans - Area B 170
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Figure No. Title Page
21 Collection Time, Bags and Cans - Area C 171
22 Collection Time, Items - Area A 172
23 Collection Time, Items - Area B 173
24 Collection Time, Items-Area C 174
25 Distribution of Cans and Bags at Collection Stops 175
26 Distribution of Containers at Collection Stops 176
27 Collection Time for Bags, Route Al 177
28 Collection Time for Bags, Route B4 178
29 Configuration of Typical Test Area for Litter Observations 179
30 Litter Distribution 180
31 Distribution of Litter by Maximum Dimension 181
32 Location of Restaurants Testing Bin Liners 182
33 Continued Bag Use, Area B4 (326 Single Family Units) 183
34 Continued Bag Use, Area C5 (85 Single Family Units,
102 Apartments) 184
35 Total Bag Usage in Apartments and Single Family Units,
Area C5 (85 Single Family Units, 102 Apartments) 185
36 Dust Particles Generated by Emptying Household Can 186
37 Test Specimen Dimensions 187
38 Distribution of Strain 188
39 Stress-Strain Curves, Polyethylene Bag Specimens 189
40 Stress-Strain Curves, Polyethylene Can Liner Specimens 190
41 Stress-Strain Curves, Polyethylene Bin Liner Specimens 191
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Figure No. Title Page
42 Stress-Strain Curves, Paper Bag Specimens, Longitudinal
Cut 192
43 Typical Pinhole Test Specimen 193
44 Apparatus for Puncture Tests 194
45 Longitudinal Strain-Time Curves, Friedman Polyethylene
Bag (2.5 mil), Narrow 195
46 Transverse Strain-Time Curves, Friedman Polyethylene Bag
(2.5 mi I), Narrow 196
47 Longitudinal Strain-Time Curves, Wagner Polyethylene
Liner (3.5 mil) 197
48 Percent Failure of Polyethylene Bags Versus U* 198
49 Acceptable Values of U as a Function of Polyethylene Bag
Thickness (Shaded Region is Unacceptable) 199
50 Can-Bag Collection Times, One-Man Crew 200
51 Can-Bag Collection Times, Two-Man Crew 201
52 Can-Bag Collection Times, Three-Man Crew 202
53 Can-Bag Costs, One-Man Crew 203
54 Can-Bag Costs, Two-Man Crew 204
55 Can-Bag Costs, Three-Man Crew 205
56 Can-Bag Services, One-Man Crew 206
57 Can-Bag Costs, One-Man Crew 207
58 Effect of Disposal Travel Time on Costs Per Service 208
59 Effect of Non-Productive Work Time on Costs Per Service 209
60 Effect of Mean Quantity of Solid Waste on Costs Per
Service 210
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LIST OF PLATES
Plote No. Title Poge
1 Photographs 211
A. Time and Motion Sequential Timer Equipment 211
B. St. Regis Paper Bag with St. Regis Holder 211
C. International (Garbax) Bag with International
Holder 211
D. Mobil (Flamegard) Polyethylene Bag with Mobil
Holder
E. Mobil (Luxriliner) Polyethylene Can Liner
Installed 211
2 Photographs
A. Collector Loading Polyethylene Bag by Holding
Handle Provided by Closure with Paper-
Covered Wire 212
B. Bin with a Slipped Liner 212
C. B and K Precision Sound Level Meter 212
D. Typical Waste Picked Up for Litter Index 212
E. St. Regis Paper Bag Rotted from Resting on Damp
Ground 212
3 Photographs
A. Closed Polyethylene Bags Ready for Collection 213
B. Street with Paper Bags on Day of Collection 213
C. Conventional Trash Cans 213
D. Street with Cans on Day of Collection 213
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SUMMARY
A. Background
1. Demonstration Location. The City of Inglewood is located in populous
Los Angeles County in Southern California and in 1968 had a population of about
94,000 persons, and an estimated 36,000 dwelling units with an average occupancy
rate of 2.6 persons per unit.
In 1957, the City established a residential solid waste collection service
utilizing two-man municipal crews and equipment for once-a-week curbside
collection of combined solid waste, less garbage. In 1961, the City experimented
with one-man collection crews, and in 1963, following an increase in the size of
their collection equipment from 20- to 35-cu yd capacity, one-man operation
was implemented.
2. Objectives. The purpose of the demonstration program was to investigate
the use of bags for solid waste storage and collection. The objectives of the study
consisted of the following: (1) evaluate the effects of disposable containers on
collection efficiency; (2) compare paper and polyethylene bags with cans for use as
solid waste containers; (3) determine householder preferences for disposable versus
reusable conventional hard containers; (4) investigate health, safety, and environmental
factors related to the use of disposable containers; (5) study alternative methods for
distributing solid waste bag systems; (6) suggest incentive programs for using bag systems;
and (7) investigate the feasibility of using polyethylene liners in large bin containers.
B. Demonstration Program Procedure
1. Study Approach. Three demonstration areas were chosen in the City of
Inglewood; two were single-family residential areas, and one contained both single
and multiple family dwellings. Each area was subdivided into two comparable routes,
one of which was the test route to receive bags, and the other to serve as a control.
A four-week pre-demonstration study was undertaken prior to the distribution
of bags to define basic field conditions in the demonstration areas. The objectives
were to: establish crew performance; determine the number of cans collected per
residential unit; measure the solid waste quantity per residential unit; and define
operating parameters for collection crews and equipment. Statistical methods were
used to establish the equivalence of the paired routes on the basis of number of
containers, quantity of solid waste, and types of waste.
Additional samples of Inglewood solid waste were taken for all study areas
during three different periods of the year to define seasonal variations in composition.
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2. Distribution of Bags to Householders. Four basic household bag systems
were evaluated during the demonstration: (1) the paper bag end holder; (2) the
polyethylene bag and holder; (3) the polyethylene can liner; and (4) a free-standing
paper bag. Specifications to supply bags and holders were offered to prospective
bidders, and bids were received from six companies.
The number of bags and holders required for the test periods were estimated for
both single family residences and for apartment buildings, from the pre-demonstration
field studies. Bogs were distributed by City collection personnel who explained the
purpose of the study to the participating householders. Each residence received three
separate distributions of bags at three-month intervals in order to allow sufficient
time to establish performance. Comparisons were made between different container
systems (cans, bags, and liners) and between different bag systems. A fourth
distribution was made to an apartment condominium to evaluate a new liner holder,
and to investigate bag collection utilizing holders on the residence property. Four
questionnaires were distributed: one at the end of the two test periods, one at the
condominium, and one to the three test areas to evaluate the householders' overall
response to the bag systems.
3. Field Data Collection. Field data were gathered on collection time, the
average quantity of waste per stop, the average number of containers of a given
type per stop, and the size of containers in use. Additional field work consisted of
counting the number of bags with punctures, tears, and those failing. Field monitoring
was continued after the 3-month bag distribution and use periods to count the number
of residences voluntarily using bags. Special field time studies and personal
interviews with bin liner users and landfill personnel were completed.
C. Results of Field Studies
1. Collection System. Time and motion studies were conducted on the six
test routes, and collection time and associated container size and weight data were
recorded. Analysis of the data indicated that on routes using bags, average collection
times per stop ranged from 17 to 25 percent lower than on routes using conventional
containers.
During the field time studies, the project engineers observed that it was easier
to handle polyethylene bags than paper bags due to the method of closure. Collection
time comparisons made between two routes using only paper and polyethylene bags,
respectively, indicated that collection time averaged about 0.02 minutes more per
bag for paper than for polyethylene bags. This difference may have resulted from the
greater quantities of waste contained in paper bags. It was not, however, statistically
significant.
Statistical comparisons of the average number of items per collection stop in
paired bag and control routes showed that there was a significantly greater number of
items per household for bag routes than for can routes in two study areas (B and C),
and no significant difference in one area (A). Although the estimated solid waste
capacity of the bags was within 5 percent of the cans, the actual capacity utilized in
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the bags was about 20 percent less than in the cans. Only large can liners were found
to contain as much solid waste as the cans. This was due to: loss of bag capacity as a
result of rolling the edge over to close the bag; and the improved compaction of solid
waste in hard containers which support the bottom and sides of the bag.
2. Public Health and Environmental Considerations
a. Noise. Measurements were made of the reduction in collection noise
resulting from replacing conventional metal containers with disposable bags. The
"noise rating number" is a measure of noise level related to probable hearing
annoyance; when it is greater than 85, hearing may be affected detrimentally. The
noise rating number of 86, measured when metal containers were struck against the side
of the collection truck hopper, posed a potential hazard to the hearing ability of the
collector. Use of disposable bags would eliminate this potential noise hazard. In
addition, a reduction in vehicular noise from the packer and motor mechanisms would
be desirable to reduce the noise level below 85. Noise rating numbers taken during
dragging and dropping of cans and bags were 37 percent lower for bags than for cans.
b. Insects. A study of fly generation in household waste bags at the City
of Inglewood was conducted in cooperation with the Department of Public Health of the
State of California. Green blow files have a life cycle which is well-suited to
breeding once-a-week between collections, and consequently are often produced in
excessive numbers in solid waste containers. Data collected on the total number of
green fly larvae migrating from conventional solid waste containers with and without
polyethylene liners showed that the amount of fly production would not be sufficiently
reduced by polyethylene liner use to warrant its recommendation for fly prevention.
The old cans, although cleaned prior to the fly study, may have acted as a fly source
even with the liners due to subsequent deposition of waste. Fly control might be
improved by using containers with open bottoms to hold the liners, as is done in
Manchester, England.
c. Litter. A measure of littering, labeled the "litter index", was deve-
loped to compare littering in different areas before and after collection „ Litter
classified by maximum dimension and surface area showed that most litter items had
surface areas in the range of 2 to 3 sq. in. and 1 0 to 20 sq in., end a maximum
dimension in the range of 1 to 5 in.
A mean litter index was measured immediately prior to collection . The
mean litter index for can routes, 71 .6, was almost double that for bag routes, 40.3.
An average of 6.1 and 4.1 $ems were found on the can and bag routes, respectively.
No litter was observed on the bag routes after collection, but litter was observed in
two areas on the can routes. Counts of spills indicated occurrences of 1 .2 percent for
the 919 bags and 0.9 percent for the 5,427 cans observed.
d. Accidents and injuries. More than half the lost-time injuries occurring
in waste collection during the six-month period studied in 1967 resulted from handling
metal or other hard cans. The main injuries were strains, sprains, and dislocations
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result-ing from lifting or carrying heavy, unwieldy cans or tripping over obstacles in
walkways. During the conduct of the two-year demonstration in Ingle wood, no
injuries to collection crews were reported as a result of bag handling, but two injuries
occurred on the can routes. The reduction in work hazards for the collector loading
bags was due to: the limited weight load capacity; elimination of the extra weight of
the can; elimination of jagged edges on cans; reduction in dust particles and pathogenic
organisms in the air; and reduced noise. Some of the detrimental effects noted with
bag use were their poor protection against sharp objects in the waste, and their tendency
to burst during the vehicular compaction cycle and scatter dust particles.
e. Microbiological and dust tests. Bacteriological plates were exposed
near containers as they were emptied into the truck hopper. It was assumed that the
number of bacterial colonies which developed on the plates after incubation was
proportional to the dust in the air. Comparison of the dust generated by use of bags
and conventional cans was made.
Bacteria and fungi plate counts were made after 24 and 48 hour incubation
times for two sets of samples, one for bags and one for cans. Analysis of the results
showed dust generation decreased over 90 percent when using bags in place of cans.
A detailed analysis of the bacteria, fungi, and yeast varieties present in
the dust samples was made to identify potential pathogens. Many pathogenic organisms
were found in the samples taken during waste collection using conventional cans.
A controlled experiment investigated the extent of dust distribution when
loading a collection vehicle with solid waste using can containers. The test results
showed that during solid waste collection under windless conditions, cans may distribute
solid waste dust as far as 14 feet from the point of dumping; thus dust is not confined to
the collection vehicle. Also the greatest dust concentration may occur some distance
from the loader in the direction the waste is dumped, and that dust may be inhaled by
the collector if he is downwind of the Reid source.
3. Landfill and Transfer Operations. The disposal of polyethylene bags
in landfills produced improvements in pushing and spreading operations, reductions in
blowing of solid waste and dust, and reductions in odor. Some problems with
polyethylene bags lodging between crawler tracks and dozer frames were encountered
in maneuvering in wet weather; and fine grading of the compacted solid waste surface
was more difficult with polyethylene bags. Calculations showed that polyethylene bags
would increase the total wet weight of plastics in solid waste by about 50 percent.
The limited biodegradabi lity of polyethylene is not expected to cause significant
problems in landfills. In addition, the combustion by-products of polyethylene are
harmless. Paper bags treated with waterproof resins would similarly have little total
environmental impact on landfill or incineration disposal.
Observations at a waste transfer station indicated that transfer station
operations were generally improved by reductions in dust and blowing litter when solid
waste in bags was handled.
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4. Commercial Bin Liners. Polyethylene liners of 2 and 3 cu yd size for use in
equivalent sized waste bins were distributed to a number of restaurants in the Inglewood
area. The restaurants cited difficulties in handling and fitting, and improvements in
sanitation, fly, and odor problems. Problems with the liners staying in bins during
dumping were reported during collection. The overall popularity of the system was
indicated by the unanimous approval of the responding users and their recommendation
for continued usage. Time and motion studies during bin collection showed an average
increase of 0.2 minutes per bin serviced. Economic analyses indicated a net increase
in cost of about $11 7 per restaurant per year would occur as a result of increased
collection time and liner cosh.
5. Householders' Preferences. Five householder questionnaires were distributed
to obtain the r-;jctions of the residents of Inglewood to the demonstration bag systems.
Questionnaire 1 was a pre-test questionnaire to evaluate citizen interest in bags
as solid waste containers. The overall reiponse indicated the present collection
service was viewed as very satisfactory, and that a change to bag systems would result
in few apparent benefits. This response was prompted by the public being accustomed
to a particular level of service and being unaware of possible improvements.
The goal of the four follow-on questionnaires was primarily to delineate the overall
effects of using bags in place of metal or plastic cans, and secondly to compare the
performance of the different types of demonstration bag systems and bag types based on
the residents observations.
The responses to the questionnaires gave consistent reports on improvements and
difficulties encountered with use of the bags. The majority of residents felt that the
use of the bags resulted in marked improvements in all areas oF solid waste management
with particular improvements noted in ease of carrying filled bags, and neighborhood
appearance, with less odor, fly, and spillage problems. Some difficulties with paper
bags were reported in mounting, filling, and closure. The paper bags also required
more storage space and were more susceptible to tearing when wet. Many of these
problems were attributable to the novelty of the systems, and would be d/ercome with
continued use and improved holders.
Polyethylene bags were waterproof and had a better meth: * of closure which
provided the collectors with a handle to grab. Polyethylene bags were punctured by
brush or pointed objects more often than paper bags, although the paper ripped more
easily after puncture. The collectors strongly favored the use of disposable bags and
in particular the polyethylene bags which facilitated loading when tied closed. The
overall response showed that the majority of the residents liked the bag systems and
wished to continue hem.
6. Voluntary L.g Use. A six-month follow-up survey to count residences
voluntarly using bags showed the* commercially available 1 .5 mil polyethylene bags
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were replacing the demonstration's specially purchased and more expensive 2.5
mil polyethylene bags; but, generally, usage of both paper and polyethylene bag
systems decreased. All users apparently discriminated between bag systems largely on
the basis of cost. A rise in use was noted in June 1970 when two local department
stores began advertising promotions for 1.5 mil polyethylene bags.
7. Notional Survey on Usage of Disposable Bogs in Solid Waste Collection
Systems. A nationwide postal survey was made to define factors affecting the use
of disposable bags for solid waste collection. A total of 205 cities representing a
population of more than 36 million people responded.
Analysis of the responses showed that although many cities did not permit the
use of bags, the majority had plans for allowing disposable bag usage in the future.
Bags were already in use in approximately 12 percent of the households of the cities
permitting their use, with 87 percent of the bags being used reported as polyethylene
and the remainder as paper bags. In most instances, the bags were purchased
privately by householders. The questionnaire responses indicated that the cities were
generally satisfied with their performance. Polyethylene bags (1.5 mil thickness)
cost less than paper bags when purchased in retail stores or at wholesale.
The cities reported that the main problems encountered in bag use were: the
susceptibility of polyethylene bags to tearing, and of all bags to attack by animals;
and the possibility of nonbiodegradability of polyethylene bogs in landfill operations.
Generally, however, these problems were not considered critical. Approximately 73
percent of the cities responded favorably to polyethylene bags as liners as opposed to
bags on holders. Only 14 percent of the cities had conducted economic studies on
possible savings resulting from the use of disposable bags.
D. Bag and Liner Materials Testing
Laboratory tests were performed on bag and liner materials to define physical
properties that directly affect their economic value and field serviceability. The
tests also helped to develop material specifications for the demonstration bag
purchases.
Tensile tests were performed to obtain stress-strain relationships for the
demonstration bag materials and to find the tensile failure levels for a number of
other bag specimens. Supplementary tensile tests were performed under a variety
of simulated field conditions to determine the effects of moisture content and
absorption, evaporation, puncture, and creep.
Tensile tests illustrated the anisotropic, non-ductile nature of the two-ply
paper specimens and the elasto-plastic nature of the polyethylene specimens.
Soaking in a variety of common household waste substances such as water, cottonseed
oil, and butter, and exposure to normal ranges of climatic temperatures did not
significantly affect the tensile strength of the polyethylene materials; the strength of
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wet paper specimens was, however, 50 percent lower on the average when soaked in
these waste substances than in the dry state. Other tensile tests showed that when
polythylene bag material was punctured or perforated the decrease in failure load with
an increase in the size of the puncture or perforation was less than the decrease for
paper. Tests showed creep to be insignificant under normal residential solid waste bag
loads.
Results from the laboratory tests were used to develop purchase specifications and
to investigate correlations between laboratory test results and field performance. The
ultimate strength and the strain energy of the polyethylene and paper specimens were
found to be significant performance indicators correlating with field failures resulting
from punctures and tears during actual use.
E. Formulation of Bag Evaluation Criteria
Bag system evaluation criteria were developed to satisfy the following objectives:
to establish minimum standards for proposed bag material specifications; to provide a
rationale for comparing bag system performance; and to formulate bag system selection
criteria. Two approaches were developed for evaluating bag systems; the first related
the properties of the bag materials to the bag failure rates in the field, while the second
was derived from consumers' preferences and field performance.
Properties of the demonstration bag materials were derived from the laboratory
tests, and a theory was developed which indicated that the energy absorption potential
of the material (the product of the strain energy and the thickness of the material) was
a measure of the field performance failure rate. This hypothesis was supported by a
variety of field and experimental data.
Since the responses to the demonstration questionnaires indicated that the rate of
failure of the demonstration bags was satisfactory to both householder and collector,
minimum values of energy absorption potential and also of ultimate tensile stress of the
demonstration bags were taken as specifications for the initial selection. Two selection
criteria, one for paper, and one for polyethylene bags, were develop*?'' as minimum
acceptable specifications in selecting bags on the basis of cost per unit volume of the
individual bags. Paper and polyethylene were treated separately due to the different
nature of their materials properties. An optimal bag materia1 Composition was not
deemed a feasible parameter for bag selection; the strength and failure criteria are
more applicable because they may be used to evaluate all bag materials. Polyethylene
bags would be preferrable to paper in wet, damp climates and for the solid wastes of
high moisture content. Bag volumes in the 32 to 36 gallon range and 55 inch circum-
ference are satisfactory for household waste disposal. Larger bags of about 40 to 45
gallons with 70 inch circumferences are required for disposal of yard trimmings because
of the larger opening and capacity to hold bulky brush.
An additional study approach was an algorithm formulation for total evaluation of
bag suitability. This approach accounted for factors which affected bag performance
other than failure rate and cost; for example, ease of bag closure, odor control, etc.
The questionnaire data indicating the importance householders attached to each
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individual factor was incorporated with the field preference ratings of the demonstration
bags to give a total rating for demonstration bags, which enabled a direct comparison to
be made between each of the bag systems. Based on the algorithm anal/sis, the poly-
ethylene bags and the polyethylene liners rated higher than the paper bags. The effect
of poor bag holder performance on bag ratings was illustrated when a revised Mobil
holder was substituted for an old model. The algorithm reflected the holder substitu-
tion in a rating change for Mobil bags. The consistency and sensitivity of the algor-
ithm ratings indicated that the format for total bag evaluation provided a workable
rationale for comparing the overall suitability of bag systems for field use.
F. System Simulations for Cost Analysis
The impact of disposable waste bags on collection efficiency was investigated
using a mathematical model developed by the project engineers. The model defined
the time required for waste collection, and by using actual cost data for labor and equip-
ment, collection costs were estimated for a particular service. Variations in field con-
ditions were included in the model to determine their effect on waste collection effic-
iency. An IBM 360 computer was used to analyze alternative simulated collection
operations.
Model simulations indicated reductions for bags over cans, using one-man crews,
as follows: collection time, 21.7 percent; man-hours per ton, 15.4 percent, on the
average, for 25 to 35 cu yd trucks; average cost per service, 6 cents (Inglewood costs);
and the number of services a collection crew completed in a normal working day in-
creased by 27.8 percent. Calculations comparing crew sizes of one, two, and three
men showed the one-man crew to be the most economical for curb pickup.
G. Collection System Management Cost Analysis
Cost comparisons were completed for seven container configurations: (I) metal
cans; (2) light duty plastic cans; (3) heavy duty plastic cans; (4) 1.5 mil thick polyethy-
lene liners in metal cans; (5) 1.5 mil thick polyethylene liners on holders; (6) paper bags
on holders; and (7) 2.5 mil thick polyethylene bags on holders. Costs were compared for
City distribution and wholesale purchase of bags, and for resident retail purchase of
bags. The present conventional can system, at retail, costs $1.05 per household per
year less than the liner-in-can system, which was the least expensive of the four al-
ternative bag/liner systems.
If the cost to the City for distributing liners could be constrained to be less than
$2.44 per household per year, the liner-in-can system would become economically
feasible.
Estimated benefits accruable to householders in the amount of $6.76 per house-
hold per year resulting from savings in can cleaning time and materials, provide an
additional incentive for bag use.
*
Mention of commercial products does not imply endorsement by the United States
Government.
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H. Implementation of a Bag System for Waste Collection
Implementation of a bag system for waste collection should start with a comprehensive
systems analysis of the collection operations. The collection time and cost savings
presented in this report apply only to curb collection where residents carry the waste
to the curb. Other collection systems such as back yard pick-up or container placement
at the curb by collection personnel, would require complete time and motion stud'es to
determine the potential savings attributable to using bags.
The following steps would be a necessary part of a complete systems analysis prior to
implementing a bag collection system:
1 . Complete extensive time and motion studies of the existing collection operation.
2. Determine the number of containers, container sizes, and the average quantity
of waste collected per residence.
3. Estimate the collection time for bags by one of the following:
a. Use Method-Time-Measurement (MTM) techniques applied to step 2, (see
Appendix 1 and reference report 2).
b. Conduct a small-scale bag use study and measure collection times on
representative routes.
4. Determine the potential savings in collection time for bags versus cans from
steps 1 and 3.
5. Select a bag or liner system using the bag evaluation criteria and algorithm
for bag suitability presented in this report. A cold or wet climate may introduce
additional factors into the selection process.
6. Estimate the collection system operating costs based on equipment, labor, and
bag costs for alternative bag purchase and distribution methods.
7. Determine the economic feasibility of a bag system. if feasible:
a. Establish an incentive program for bag system implementation based on the
applicable cost, environmental and public health considerations.
b. Develop an educational action program to introduce a bag collection system.
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CONCLUSIONS
1. Polyethylene and paper bags are satisfactory solid waste container replace-
ments for cans. Results of a Nationwide survey conducted by the project engineer
indicated that bags performed satisfactorily in all climates; and that both public and
private bag distribution methods were practiced.
2. The most frequently cited reasons for the slow rate of bag-system acceptance
were management difficulties in achieving economical bag distribution and storage
methods.
3. Prior to using bags, householders in the Inglewood demonstration areas were
not concerned with further improvements in their collection system due to three fac-
tors: 1) the implied change in daily routine; 2) anticipated increase in cost; and 3)
satisfaction with the existing system. After using the bags, however, the Inglewood
householder participants indicated positive acceptance of the demonstration bags and
can liners.
4. Reduction of litter and the absence of empty cans at curbside after col-
lection improved the neighborhood appearance. The bags were directly responsible
for reducing collection noise, dust generation during truck loading, and accidents
and injuries associated with overloaded and/or sharp-edged cans. There was also a
minor reduction in blowfly larvae counts with bag use.
5. Although the thin 1.5-mil, 32-gal polyethylene bag materials and con-
struction commonly available as of 1970 were satisfactory, bags of 2.5 mil or thicker
were torn or punctured less frequently.
6. The polyethylene bags and liners were waterproof, odor proof, required
less storage space than paper bags, and closed easily. The paper bags lost 80 percent
of their strength when wet, did not constrain odors, required 18 times the storage
space of polyethylene bags, and were difficult to close when filled with waste.
7. At the break point, the dry tensile strength of the paper bag material was
five times greater than that of the polyethylene material. The failure load of poly-
ethylene bags decreased less than that of paper bags with increasing perforation hole
size.
8. A properly designed holder is a desirable part of a bag system. Demon-
stration holders with malfunctioning lids prompted many negative comments, and in-
fluenced the householder against the bag type being used. An improved holder re-
sulted in greater bag-system use satisfaction.
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9. A lack of uniformity in the bag and holder sizes of competitive manufactur-
ers sometimes precluded the use of one manufacturer's bag product on the holder of
another manufacturer.
10. Simple bag closure ties were not available for paper bags, but were readily
available for plastic bags.
II. The solid waste collectors indicated they favored the bags and liners over
cans. They were saved the work of lifting and replacing cans and their covers after
emptying. The polyethylene bag ties provided the collector with a convenient hand
grasp which facilitated bag pick-up; the handgrasps contributed to a statistically insig-
nificant 0.02 minutes less collection time per bag for polythylene bags over paper.
12. The full load capacity and number of units collected to fill the refuse col-
lection vehicle were not significantly affected by bags when compared to conventional
containers.
13. Polyethylene and paper bags reduced dust and litter in transfer station
operations. Polyethylene and paper bags were observed to reduce litter and dust, and
improve landfill spreading. Polyethylene bags increased by about 50 percent by wet
weight the amount of non-biodegradable plastic material in the municipal landfill
solid wastes. Polyethylene bag incineration would produce carbon dioxide and water
vapor.
14. On the basis of utilized container capacity in volume and filled weight,
about five 32-gal bags were required to replace four conventional 32-gal cans; analy-
sis of field data indicated significant increases in the total number of items placed for
collection from residences using bags over those using conventional containers. Paper
bags were generally filled to a greater percent of their ultimate capacity than polye-
thylene bags, but to a lesser percent than cans.
15. Based on model simulation studies using field data and assumptions derived
therefrom, paper and polyethylene bags reduced the average net solid waste curb col-
lection time and related costs below that for cans. The use of bags instead of cans
reduced maximum net solid-waste curb collection time as follows (including travel
time between stops and to landfill, using a 25-cu yd truck): one-man crew, from 53
to 41 man-minutes/ton (23 percent); two-man crew, from 98 to 76 man-minutes/ton
(23 percent); and three-man crew, from 123 to 99 man-minutes/ton (20 percent).
Corresponding reductions in collection-system cost per service were about 24, 24.3, and
and 17.5 percent for one-, two-, and three-man crews, respectively. The one-man
crew is the most economical crew size. These cost reductions do not include the cost
of bags, holders, and their distribution.
16. The use of bags increased collection-system productivity in the demonstra-
tion area by an estimated 27.8 percent in the number of stops serviced in an 8-hour
day by a one-man crew and 35-cu yd truck, compared with that achieved with the use
of cans.
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17. Polyethylene 1.5 mil bag liners using cans as holders were calculated to
be an economically Feasible solid-waste container system for curb collection in
Inglewood under the following conditions: wholesale purchase of the liners by the
City; liner distribution costs of $0.75 or less per residence per year; and the use of
existing cans as liner holders.
18. Criteria for bag system selection were defined separately for polythylene
and paper; the optimal bag provides the greatest strength at minimum cost within the
following constraints:
Polyethylene; minimum cost per unit volume
2
subject to: strain energy > 10.0 in-lb/in
ultimate strength (stress) > 2000 psi
Paper; minimum cost per unit volume
2
subject to: strain energy (dry) > 2.0 in-lb/in
strain energy (wet) > 0.5 strain energy (dry)
The selection of polyethylene over paper may be required in wet climates and for
disposing of solid wastes high in moisture content. An optimal bag composition and
volume are not in themselves adequate criteria for selecting bag systems.
19. An algorithm for evaluating bag/liner system suitability was developed.
It may be used to compare the relative merits of alternative bag systems, to locate
defects in either the bags or holders, and is capable of being expanded to include new
rating elements as they are defined. The algorithm data reflected the effect of a mal-
functioning holder lid on the total bag-system rating.
20. The large (2 and 3 cu yd) demonstration bin liners improved sanitation and
were well received by the restaurant users. The liners were, however, relatively
costly and required more installation and collection time than unlined conventional
metal bins.
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RECOMMENDATIONS
Further studies are recommended in the following areas:
1. A follow-up program to formulate an optimal route collection system for
the entire City of Inglewood using bags.
2. A study to determine optimum bag dimensions to set improved uniform stand-
ards for capacity, circumference, area of bag opening, and wall thickness, and to
develop improved bag holders. Standardized, optimal bag dimensions could improve
the working (used) capacity of the bags by reducing bag-filling problems cited in the
present study; and standards for a universal bag-holder mounting and protection system,
including a quick disconnect device for installing and removing both polyethylene
and paper bags, would increase the efficiency and flexibility of the bag collection
system.
3. Further back yard pick-up and other specialized solid waste collection
system studies to evaluate the cost-benefits of using bags.
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I. INTRODUCTION
A. Generol
Until recently, bags for solid waste have not received the widespread use in the
United States as in some of the northern West European countries. Primary reasons for
this slow acceptance may have been due to: the gradual evolution of collection
methodologies in the United States, uncertainties of the potential benefits, the costs
for the bag systems, the need to develop satisfactory methods for distributing bags,
and the lack of extensive promotional activities by bag distributers.
The National Refuse Sack Council reported in 1968 that 37 small American
communities were using paper bags. They indicated that all of these communities,
after once experimenting with the use of bags in a significant number of residences,
decided to continue their use even though it appeared that additional costs were
involved.
A variety of bag systems are currently being used. In some instances, the
municipalities provide paper or plastic bags either free of charge or at cost. When
bags are provided they are distributed by the collection workers or are made available
to residents at convenient locations in the community. When the municipality does
not provide bags, the individual householder must purchase them commercially. In
addition, many types of enclosed and open bag holders are available for use with
either paper or plastic bags.
The City of Inglewood solid waste collection system has been employing one-
man crews for municipal collection service since 1960. The high level of service
and economic success of this system has received attention since its inception. The
City participated in a USPHS-contract study of one-man and multi-man crew size
collection systems in 1967-68 to define the nature of the savings that could be
achieved using a one-man crew. The results of this study were presented in a final
report* published in mid-1969. The report and much of the detailed field work
conducted during the one-year study period provided valuable basic information
which was directly applicable to the bag demonstration program.
B. Objectives
The objectives of the demonstration program were to: (1) evaluate the effects of
disposable containers on collection efficiency, (2) compare the use of polyethylene
and paper bags as solid waste containers, (3) determine public preferences for the use
of either disposable bags or conventional hard containers, (4) develop incentives for
the use of improved containers,(5) investigate environmental health and safety factors
related to the use of containers, (6) study alternative procedures for distributing bags
and holders, and(7) investigate the use of polyethylene liners in large bins.
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II. BACKGROUND ON BAG USE
A. Paper Bags
The practice of placing solid waste in a paper bag until the bag and contents
can be discarded is common practice. What seems more natural in a kitchen, for
example, than to place garbage and other solid waste into a small bag for subsequent
disposal? However, providing the public with specially fabricated large bags and
holders to replace traditional galvanized metal or semi-rigid plastic cans is innovative.
Experimentation with paper bags for use as can liners began as early as 1 938 in
the Borough of Croydon in London. The impetus for the British paper bag solid waste
storage system was primarily the result of the World War II shortage of metal; this was
also true in both Sweden and Germany. However, other special virtues of the system
were realized when in 1 954 bags were adopted for the hygienic disposal of soiled
hospital dressings, infected linens, and other medical solid waste.
The introduction of a specially designed bag holder provided a means for
supporting the bag in a semi-rigid receptacle and led to the further development of
the paper bag system. Holders were first used in Scandinavia, and the first notable
installation was probably in the town of Sandviken, Sweden, north of Stockholm.
Since that time, Sweden and Denmark have led the way in technological improvements
of paper bag systems.
In the Scandinavian countries, nearly all large disposable bags are made of wet
strength paper. A major reason for this is that the plastic companies are owned by the
well established paper industry. Thus the polyethylene bags have not competed with
paper bags. In 1970 at Copenhagen, Denmark, paper bags and holders
were distributed and maintained by the City free of charge to the house ho Icbrs.
Ownership of the holders, however, remains v/ith the City. Replacement oags are
distributed to the householder by the municipal collector during back yard pickup of
solid waste.
The United Kingdom is believed to have the greatest n< tiber of homes served by
bag systems, which include those in such large cities as Manchester and parts of London.
It is estimated that about 10 percent of the municipalities have switched entirely to the
use of disposable bags since the initial development of systems began in 1 958.3 |n I960,
following six months' experimental use of the paper bags in 250 homes, the rural Swale
Borough District Council decided to adopt the system in a district containing 7000
homes. The United Kingdom also achieved success with the adoption of the paper bag
system in the first new hospital to be built in the United Kingdom after World War II.
The Ministry of Housing and Local Government, following a four-year investigation of
solid waste storage and collection, endorsed the bag system in 1 967. During the four-
year study, three systems—ordinary metal cans, dustless bins, and bags—were evaluated.
Recently, the usage of polyethylene bags has become increasingly popular because
polyethylene bags are waterproof, less expensive, require less storage space and are
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easier to distribute. Estimates of the annual consumption of low density polyethylene
for manufacture of bags in Britain have been increased from 1,000 tons in 1968 to
2,000 tons in 1970 and are expected to increase another five-fold by 1980.4 Many
municipalities were using polyethylene bags in 1970 on a test basis. It was common
for polyethylene bags to be used on paper bag holders. In the City of Manchester,
novel containers were developed for polyethylene bag liners; the containers have no
bottom and are in the shape of an inverted truncated cone. The collector lifts the
container and cover off the bag to allow its' removal to the collection vehicle and
leaves a new liner on top of the container.
In 1970, it was determined by the project engineers that the local public
authorities in the United Kingdom generally favored bag holders, and many authorities
provided them at residences. However, the householders were somewhat reluctant to
change, as they were reported to have favored the usage of bags as liners in metal
cans. Many municipalities still use the old dust less system consisting of a metal or
plastic container with special attached cover, and collected by a special vehicle
provided by the municipality.
The use of bags for solid waste storage and collection in the remainder of Europe
has been slow to develop in spite of intense promotion by paper bag companies. Only
Germany showed some acceptance of the system. Eurosac, an association founded by
paper bag manufacturers from 14 countries in Europe and Scandinavia, established a
committee to facilitate the interchange of information and experience.
The pasted square-bottom paper bag has been used primarily in continental
Europe and Scandinavia, while the United Kingdom has used the sewn bottom bag.
In the United Kingdom it was less costly to manufacture the sewn bottom bag due to
the availability of applicable types of manufacturing equipment, but the reverse was
true in continental Europe and Scandinavia. Resins compounds and asphalt have been
used as a means of bag waterproofing. The annual bag usage in Europe grew from
110 million in 1965 to 166 million bags in 1966, an increase of 51 percent.
Paper companies in the United States began promotion of the paper solid waste
bag system in 1 962. In 1967, the estimated total annual sales of paper solid waste
bags in the United States had grown to about 20 million, and ten communities, with
individual populations of 25,000 or less, required the use of paper bags by ordinance.
There were, in addition, some 15 other communities that supported an optional system
wherein local government supplied bags to the public at cost. In the United States,
two-ply paper bags, impregnated with resin as a means of waterproofing, are commonly
used.
The United States government has supported some research in the United States on
the use of bags for residential solid waste. The 1965 Solid Waste Disposal Act provided
grants to study solid waste problems. In 1966, a three-year grant was made to
Barrington, Rhode Island, to demonstrate the paper bag system. Also, in 1962, the
American Public Works Association, in conjunction with the Kraft Paper Association,
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examined the paper bag system under widely varying climatic conditions in four
representative cities.5
In September 1968, the National Refuse Sack Council reported that 19 small
cities required use of the paper bag system. Eighteen other cities were reportedly
using the system on an optional basis, with the householder given the option of using
the system if desired. The Council reported that a total of 90 towns in 1968 were
involved in testing or special evaluation programs of the paper bag system. Many
industrial, institutional, and commercial organizations were also users.
B. Polyethylene Bags
In contrast to the National Refuse Sack Council's concerted community
promotional program, the polyethylene bag manufacturers, up until 1969, concentrated
on the individual consumer as a market for their solid waste bag products. The
gathering of information on polyethylene bag usage for solid waste containers in the
United States has been difficult since there is no available industry-wide data.
Individual companies have provided information regarding their own activities;
however, they have been reluctant to divulge statistical data that might benefit
their competitors. In 1969, the National Sanitation Foundation formulated proposed
minimum criteria for polyethylene bags.
Manufacturers of plastic bags have conducted marketing tests for their products
in selected communities located in various areas of the United States. For example,
the Union Carbide Corporation tested plastic bags in about 850 households in
Brockton and Maiden, Massachusetts, from July to August, 1968. The positive
response led Union Carbide to initiate national marketing and advertising of their
waste bags in supermarkets and hardware stores. Perhaps the earliest tests of
polyethylene bags in the North American continent were those conducted during 1965
at Toronto, Canada. Toronto authorities0 reported that 140,000 solid waste bags were
distributed to some 10,000 locations in the City. Other metropolitan Toronvo
communities have tested polyethylene solid waste bags and encouraged thair use.
Montreal has considered large scale use of polyethylene solid waste begs following a
test period during Expo '67.
In 1965, tests of disposable polyethylene liners were conducted in the
neighboring Cities of Lebanon and Monroe, Ohio. & A four-week test was conducted
using polyethylene bags. In March 1968, 40 to 50 percent of the residents in the two
latter Cities were using bags. Other cities in Ohio, Michigan, Maine, and Texas
were also utilizing plastic liner bags. 8 Phillips Films Company, Inc., a subsidiary of
Phillips Petroleum, following their marketing studies predicted that a 30 million dollar
minimum annual market in municipal polyethylene liner bags would develop by 1973. &
Based on a cost of 5$ per bag, this 30 million dollar annual volume represents about
600 million plastic bags per year.
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Important polyethylene disposable bag waste studies were completed in New York
City in 1969 over an eight-week period. During the test some 17,000 households in
various locations in New York City utilized the bags. Nine member companies of the
Society of the Plastics Industry, Inc.: The American Can Company, Ethyl Corporation,
Extrudo Film Corporation, Gulf Plastic Products Company, Mobil Chemical Company,
Phillips Films Company, Sinclair-Koppers Company, Union Carbide Corporation, and
USI Film Products, a Division of U. S. Industrial Chemical Company, in conjunction
with the Society, contributed approximately 400,000 polyethylene solid waste bags for
the test. The results of the test were favorable and led to the decision by authorities
in the City of New York to modify their Health Code to permit, but not require, the
use of plastic or paper bags for solid waste.
Other major cities in the United States experimenting with or permitting the use
of plastic solid waste bags in 1970 included: Kansas City, Missouri; Flint, Michigan;
Warren, Michigan; Kenosha, Wisconsin; and Alexandria, Virginia. The project
engineers conducted a National survey of solid waste bag usage which revealed that
a large number of cities throughout the Country are now permitting the use of
disposable solid waste bags. A few cities are participating directly in the purchase and
distribution of these bags to residents.
An indication of the potential size of the United States' market for disposable
waste bags can be derived from the approximately 55 million households in the United
States. Assuming an average bag usage of three per week at an average cost of $0.05
per bag, there would be a potential 400-million dollar annual market.
An impetus to the use of polyethylene bags has been the threat of strikes by the
local collection workers. This threat has caused many local authorities to stockpile
polyethylene bags. During strikes, the bags are distributed to householders by the
authorities. Strikes have proven to be a major method for the introduction of
polyethylene bag systems. To a lesser degree, paper bags have also been used during
collection system strikes in 1969-1970.
C. National Survey on Usage of Disposable Bags
in Solid Waste Collection Systems
A total of 205 cities in 43 states and the Virgin Islands, representing a total
population of 36,448,000, responded to a nationwide mailed questionnaire survey on
the use of disposable bags for solid waste collection. The survey questionnaire is
presented as Appendix E. Of the 188 cities which responded to the question
concerning city regulations, 55.4 percent 004)° permitted the use of bags and 44.6
percent (84) did not. The responding cities who allowed use of bags estimated that
12.2 percent of their householders used disposable bags, of which 87 percent were
polyethylene and 13 percent paper. Of the 158 cities which replied to the question
concerning future usage, 75.3 percent 0 1 9) indicated they had plans for future
disposable bag usage.
Numbers in parentheses denote the number of cities providing data.
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Disposable bags were purchased by the householders in 86.0 percent (116) of the
135 responding cities. In 7.4 percent (10) of the cities, the city sold the bags. In
3.0 percent (4) of the cities, the city supplied the bags free of charge. The disposable
bag sizes most often used were in the 20-30 gal range. Of the 78 cities which
responded to the question on bag size, 82.0 percent (64) used bags in this size range.
The cost of the bags ranged from 7 to 15 cents for paper bags, and from 4 to 12 cents
for polyethylene bags. Distribution costs were incurred by 3.5 percent (5) of the 136
cities supplying information. The city authorities were asked to give their opinion of
the householders' reaction to the disposable bags. A 1 to 10 rating scale was used,
ranging from very unsatisfactory to very satisfactory, respectively. The overall rating
response of 6.92 showed that the city authorities believed the householders were
satisfied with the disposable bags.
Several problems were reported resulting from the use of disposable bags. Of
the 1 20 responding cities, 24.2 percent (29) reported that the polyethylene bags tore
easily because they were too thin or overloaded. In 17.5 percent (21) of the cities,
it was reported that cats and dogs sometimes tore the bags open and scattered the
waste; 6.7 percent (8) of the cities were concerned that polyethylene bags and their
contents would not disintegrate when buried in a landfill; and 5.0 percent (6) of the
cities noted that bags sometimes burst open during loading due to their being improperly
tied. No problems were reported by 42.7 percent (61) of the responding cities.
The city authorities were asked if they favored polyethylene bags as liners or as
disposable solid waste containers with holders. Of the 144 responses, 73.1 percent
(98) favored polyethylene bags as liners, and 26.9 percent (36) favored polyethylene
bag and holder systems. Of 140 responses concerning bag preference, 69.3 percent
(97) indicated polyethylene bags as being superior to paper bags, and 30.7 percent (43)
indicated paper bags as being superior to polyethylene bags. Only 14.2 percent (24)
of 169 responding city authorities were aware of any private collector firms which
supplied disposable bags to householders. The questionnaire asked whether 'he cities
had conducted any studies to determine cost savings resulting from the use of disposable
bags. Of the 177 responses, 14.1 percent (25) reported having conducted studies, and
85.9 percent (152) reported they had not conducted studies.
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III. AREA DESCRIPTION
A. General
The City of Ingle wood is located within Los Angeles County in Southern
California, as illustrated in Figures 1 and 2. The County of Los Angeles had an
estimated January 1, 1970 population of 7,154,845 persons, of which Inglewood
accounted for less than 1.4 percent, or about 94,000 persons. The population of
Inglewood has grown with that of the Los Angeles area; it increased from 63,390 in
1 960 to an estimated 94,000 persons in July of 1968. This gain of 37 percent has been
directly related to the demand for close-in housing created by the expansion and
growth of the Los Angeles Metropolitan area. The City of Inglewood Planning
Department has projected a 1 980 population of 125,000. Residential zoning density
in the City, based on 1960 census data, varied from a low of 6.0 persons per acre to
a high of 21.1 persons per acre. In 1968, an estimated total of 36,000 dwelling units
were available, indicating a minimum average occupancy of 2.6 persons per dwelling
unit.
Selected climatological information for the Inglewood area during the study
period is presented in Table 1 .
B. Solid Waste Collection
The City of Inglewood in 1957 established a residential solid waste collection
service utilizing municipal crews and equipment. Prior to 1957, combustible waste
was disposed of by householders in their private back yard incinerators. Wet garbage
was collected twice weekly by a private contractor for disposal to hog ranches. The
City maintained once-o-month collection of brush and yard trimmings. After 1 957,
the City initiated once-a-week curbs! de collection of combined waste, less garbage,
using two-man crews. Historically and currently (1970), the City encouraged unlimited
solid waste quantities for collection provided the householder's waste materials
conformed to the municipal ordinance. The City's 1970 ordinance requires a maximum
container plus contents size and weight of 40 gal and 60 Ib, respectively; brush has to
be tied in bundles not exceeding 4 ft in length, 2 ft in diameter, and 60 Ib in weight.
During the 1968-70 demonstration test period, once-a-week collection of combined
waste was provided.
In 1961, following the initiation of combined collection of all types of waste at
the curb location, the City of Inglewood experimented with one-man collection crews.
Combined waste collection was made possible by a change in the Los Angeles County
solid waste ordinance to permit disposal of wrapped garbage in sanitary landfills.
The implementation of one-man collection operations by the City of Inglewood
was prompted by the availability of large size collection equipment with each vehicle
traveling the relatively long haul (30-mile round trip) distance to the Los Angeles
County Sanitation Districts' Mission Canyon landfill disposal site, shown in Figure 1 .
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A transfer station was considered as an alternative procedure; however, its use was
determined to be less economical than the aforementioned method. Historical
information describing the collection system tonnage and man-hours is presented in
Table 2. Performance rates were calculated based on paid direct collection labor
hours including supervisory personnel and tonnage from scale receipts. Collectors
were paid for a minimum of eight hours work each day. Average load sizes have
increased partially as a result of converting the collection vehicle fleet from 20 cu yd
trucks capacity common in the 1960-62 period to 25 and 35 cu yd capacity trucks In
the 1964-70 period. In 1970, the City of Ingle wood collection fleet consisted of
eighteen 35 cu yd and three 25 cu yd collection trucks.
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IV. AREA EVALUATION AND DEFINITION
A. Study Methodology
Control studies were undertaken prior to the distribution of candidate bags to
define basic field conditions within the demonstration areas; to establish crew
performance collecting conventional hard containers; to ascertain the comparability
between the study areas; and to define operating relationships between collection
crews and equipment. Other special field work completed prior to the distribution of
the bags included a noise study and a survey of resident attitudes toward the waste
collection system used prior to the demonstration.
Three test areas, designated A, B, and C, were chosen following field analysis
and discussions with City of Ingle wood authorities. Street maps of the three test areas
and their location within the City of Ingle wood are shown in Figures 3 to 6. Areas A
and B are located in single-family residential areas, whereas Area C contains both
single and multiple-family residential dwellings.
Each area was subdivided into two waste collection routes: one to receive bags
during the study; the other to continue using conventional containers as a control for
evaluation and comparison of differences resulting from the use of bags.
Each route size corresponded to the daily work assignment for one crew. The
same truck and crew were to be employed on each route for the duration of the study.
The rate of collection as measured by man-hours per ton, is dependent upon the
solid waste weight collected per stop; the number, type, and location of containers;
the work rate of the collector; the travel time between collection stops; equipment
characteristics; and the haul time between the route, landfill and garage. Daily and
seasonal variations in solid waste quantity, weather, and human factors affect crew
performance. Each collector used the same type of equipment and all collections were
made from the curb or alley location to minimize the effect of these variables in the
comparison study. Statistical analysis was used to establish the comparability of the
paired routes in each of the three study areas.
B. Route Information
The preliminary Held studies were conducted during the Fall of 1968 and
consisted of determining the following data for each route:
1. Type and number of residences.
2. Type and number of waste containers at each collection stop and the
associated collection times.
3. Average quantity of solid waste per collection stop in Ibs.
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4. Route mileage.
5. Lot widths in ft.
6. Incidences of container spills.
7. Travel time between collection stops in min.
Individual times for collection and travel were obtained with incremental time
recording equipment, illustrated in Plate 1A. Times were recorded to tlie nearest
hundredth of a minute. Video tape recordings were also made to evaluate motion-time-
measurement (MTM) data.
Four weeks of preliminary field studies were conducted on each of the six routes.
Statistical analyses were completed on selected data as tabulated in Tables 3 through 8.
Table 3 contains the number and type of residences and the length of each route.
Lot widths in Areas A and B averaged 50 ft. Lot widths in Area C were greater and
varied widely due to subdivision for apartment houses. Tables 4 and 5 show the mean
and standard deviation of the number of containers located at each collection stop.
Table 4 includes cans only, whereas Table 5 includes cans and all other items placed
at the stop for collection. Single family homeowners typically used 32 gal capacity
galvanized iron metal cans, while apartment houses typically used 40 gal galvanized
iron metal cans. Collection stops were classified as either single or multiple family
residences. The bottom row of numbers in each table indicates the total number of
data points comprising the sample.
Tables 6 and 7 contain the mean and standard deviation of the collection time
per stop and the travel time between stops, respectively. Data for three week; of field
study is reported in Table 6 because during one week the trucks on some routes were
operated by different collectors.
C. Comparative Analysis
9
A test of significance was conducted on the mean number of cans and other
items (cardboard containers, etc.) per stop for paired routes. The comparisons between
routes were made for each week of the four-week field study. Table 8 contains results
of one series of calculations for paired routes Al and A2, and is representative of
similar calculations made for routes in Areas B and C.
Since the calculated values for the significance level (U) in Table 8 lie between
+1 .96, it was concluded with 95 percent confidence that the number of items placed
Tor collection at each stop was similar in routes Al and A2. Calculations similar to
that of Table 8 revealed satisfactory comparability at the 5 percent level of
significance between routes B3 and B4, and C5 and C6 for the number of cans and
items per living unit.
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Table 9 indicates the average quantity of solid waste collected per residential
unit. The data was obtained by weighing the contents of each fully loaded truck and
dividing by the actual number of residential units served by the truck.
The lower quantity per living unit in Area C is believed to reflect a lack of yard
trimmings in the apartment house waste. Commercial gardeners normally removed yard
trimmings from these latter apartment houses as part of their work activities .
The work performance level of collectors operating in the study areas was estab-
lished as a base to identify and measure changes in collection efficiency resulting from
the use of bag systems. Measurements were made over a four-week period to establish
the time required for each crew to load cans, and combinations of cans and other items.
Other items are defined as one-way containers, such as bags, boxes, and bundles of
newspapers, and yard trimmings, etc. The average time to collect a stop composed of
1,2,3, ... 7 cans and a similar number of other items was plotted; stops having greater
than seven items comprised less than 5 percent of all stops and therefore were not in-
cluded in the figures. The performance of collectors on paired routes, as represented
by a least squares line of collection times, calculated from data on all stops and items,
is illustrated in Figures 7 through 12. Similar comparisons of collection time for bags
were made following the demonstration tests.
Examination of the figures indicates that collectors operating on routes Al and
A2, and on B3 and B4, were similar in their rates of loading for cans and other items.
Collectors working in Areas C5 and C6 were somewhat dissimilar when compared to
those operating in Areas A and B. The differences were attributed to the larger capac-
ity containers employed at the apartment houses in Area C since the same routes, col-
lectors, and vehicular equipment were utilized when bags were distributed for field
testing. The time to collect a given number of cans only was greater than the time to
collect an equal number of items (including cans).
D. Composition of Inglewood Solid Waste
A sampling program was initiated in the Fall of 1968 to determine the composition
of Inglewood residential waste. Samples were obtained from study Areas A, B, and C
during three periods of the year to account for seasonal variations. There were a total
of 1,522 collection stops in the three study areas. The number of stops sampled in the
study areas was selected to give a statistically reliable sample of the total population
of stops in the three areas. The number of samples taken in each area was proportional
to the total number of stops in the area and was based on the measured variations in the
quantity of waste per stop shown in Table 9. The confidence level for the refuse sampl-
ing program was 60 percent. Locations for sampling within each area were chosen using
a random number table. Samples were taken during one-week periods in November 1968,
February 1969, and July 1969. At each stop, the weight of solid waste and the number,
type, and weight of each container were recorded.
The solid waste materials were subsequently hand segregated into five categories.
Typical waste materials grouped into each category on the bcsis of material composition
were as follows:
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Class 1 (Low Moisture Fibers) Class 2 (High Moisture Fibers)
Paper Grass
Cardboard Leaves
Lumber Hedge Trimmings
Cloth Branches
Leather Green Wood
Class 3 (Metals) Class 4 (Inert Materials)
Ferrous Plastics
Non-Ferrous Rubber
Glass
Class 5 (Putrescibles) Ceramics
Concrete
Food Scraps Dirt
Laboratory samples were taken for organic and moisture content analysis. Table
10 indicates the results. The Class 2 materials have the highest average moisture content;
these materials, however, absorb very little moisture but may hold some on their surface,
The Class 1 materials, while low in moisture content, are high in moisture absorption
capabilities. Class 5 materials varied the greatest in moisture content (558.9 to 20.8
percent, dry weight). Class 1 materials are of major concern since they absorb large
amounts of water during rainfalls; the waste samples collected in area B during
February 1969 (Table 10) experienced a heavy rainfall prior to and during sampling,
which was reflected in the exceptionally high moisture content of the Class 1 materials.
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V. DISTRIBUTION OF BAGS TO HOUSEHOLDERS
A. Specifications For Bag Purchases
Specifications prepared for the purchase of bags and holders for use during the
demonstration were based upon suggested National Refuse Sack Council specifications
modified by results of the laboratory studies. Separate specifications prepared for the
purchase of polyethylene and paper bags with suitable holders are included as Appendix C.
The preparation of specifications was complicated by the wide diversity in
commercially available bag sizes and holders. Although it was desired to permit all
potential bag or holder manufacturers to submit a bid, it was necessary to limit the
alternatives so that meaningful field studies could be made. The specifications provided
options for two sizes of paper and two sizes of polyethylene bags. Only the polyethylene
bag manufacturers were able to manufacture specific bag sizes different from their normal
product line and in the quantities desired for the field studies. Polyethylene bags of 1 .5
mil thickness initially were not considered strong enough, but since they are sold
commercially and used in many communities, a 1.5 mil liner was subsequently purchased
for the demonstrat ion.
Closures for the paper system were not available when the specifications
were formulated; however, a closure on the filled bag was desired. A wire tie closure
was common for the plastic bag system. Specifications requested paper bag manufacturers
to indicate their company's closure system. No response was received from any paper
company on this item of the specification.
The use of the bags in apartment units led to the specification of a larger than
normal size can liner fabricated from polyethylene material for use in 40 gallon
containers. A proportionally heavier thickness was specified to handle the additional
weight of refuse expected in these larger containers.
B. Bid Analysis
Specifications to supply solid waste bags and holders for the demonstration
studies were offered to prospective bidders in February 1969. A list of companies who
indicated interest in supplying bags for the studies is included as Appendix D. The bidders
list is not intended to be a complete tabulation of national bag manufacturers. Bids were
received from six companies, two of which offered to supply both paper and polyethylene
bags. The analysis of the bids received was based upon the following criteria: need
for the purchase of discreet quantities of alternative bag and holder types in order to
meet project objectives; compliance with specifications; and price.
Bags and holders purchased for field studies are summarized in Table 11 .
Three basic bagging systems were evaluated during the conduct of the demonstration.
These included: the paper bag and holder; the polyethylene bag and holder; and the
polyethylene liner using conventional hard containers as holders. A small number of free-
standing paper bags were also tested.
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These systems are illustrated in Plates IB, 1C, ID, and IE.
C. Bag Distribution Schedule
Three separate distributions of bags were made as follows: the first in each of the
three study areas; the second in Areas B and C; and additional special distributions in
Area A1 and the Briar wood condominium. The distributions, summarized in Figures 13
to 16, were designed to enable householders and apartment building managers to make
comparisons between alternative bag systems.
Demonstration residential units in Areas B and C, and the Briarwood condominium
were allocated three-month bag supplies for each candidate system tested, and units in
Area A were given a 6-month supply. At the close of the initial three-month test period
the cooperating householders were asked to complete a questionnaire (see Appendix E2,
Questionnaire 2) and they were then supplied with a different bag system. At the end
of the second three-month period, Questionnaire 3 (Appendix E3) was distributed to
obtain comparative evaluations of the different bag systems used by each resident.
D. Allocation Criteria
The allocation program was designed to provide a specific bag system and initial
bag supplies for testing in residential living units in the three study areas. Estimates
of the rate of bag usage were used to project the number of holders required for each
test apartment complex. Apartment managers handled the bags.
The initial assumptions used for the allocation of bags and holders to residences
in each of the study routes for the first distribution were as follows:
Single family homes:
bag on holder - average usage of 3 bags per week
liners for container - average usage of 2 liners per week
Apartment buildings:
holders - one for every three apartment units
liners and bags - two per week per apartment unit
Estimates of the rate of bag usage for the second and third distributions were
based on field counts of actual bags used by residents during the initial demonstration
period, and the allocation program was modified to distribute bags on the basis of their
use per household during the first three-month period.
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E. Distribution Method
Regular City of Inglewood collection personnel distributed bags and holders to
the participants in the study. Based on the allocation program, the designated number
of bags for the duration of the study was estimated and pre-packaged for each residential
and apartment unit. A master list for each route was prepared indicating the resident
or apartment house manager's name, the number of bags by type, and the number and
type of holders delivered.
Representatives from two bag manufacturing companies assisted in explaining
the purposes of the study and the proper procedures for use of the particular bag system
to the study participants. The residents were instructed on the significance of their
participation in the study, and they were asked to use their bag system exclusively
during the test period. In general, the residents were cooperative. Only two of the
households, or 0.7 percent contacted, on route Al refused to use bags on the first
and second distributions, and one household, or 0.3 percent, refused on route B4
for the first two distributions.
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VI. DEMONSTRATION FIELD STUDIES
A. Collection Operation Studies
I. Effect of Bags on Collection Time. Following the distribution of bag sup-
plies and holders in the three demonstration areas, field studies were initiated to eval-
uate the effects of bags on the solid waste collection system. The two more comparable
routes, Al and A2, were chosen for gathering time and motion data. Route Al was pro-
vided with bags and route A2 remained a can route to act as a control on changes in
collection operations attributable to factors such as weather, seasons, or solid waste
character and quantity. Time and motion data was obtained for each area prior to the
use of bags on October 22, 1968.
Collection time per stop for all items was recorded to the nearest two-hundreths
of a minute. The stop times from the route before and during bag use were separately
summarized in ascending order of magnitude and grouped into appropriate time intervals.
The average number of items per stop on Route Al were 3.93 and 4.21 on 10/22/68
and 5/20/69, respectively, and on Route A2, 4.26 and 3.88 on 10/22/68 and 5/20/69,
respectively. The percentage of stops in each time interval was cumulatively summed in
ascending order of magnitude to derive cumulative distribution curves which are plotted
in Figures 17 and 18. A comparison of the plotted results illustrates the collection time
savings attributable to the bag system. The median stop time for collection with cans
was 0.5 min, and with bags 0.3 min, a median savings of 0.2 min per stop with bags.
No random variations in median collection time, as illustrated in Figure 18, were ob-
served in the control route. Thus, the variation indicated in Figure 17 is attributed
to the use of bags.
Additional time studies were completed over a four-week period. Container data
and associated collection times were recorded. Following tabulation, the collection
times for the various numbers of cans, bags, and other container items were calculated
for collectors operating on the six test routes. The data is represented by least squares
lines on Figures 19 through 24. The tests indicated that the collection *Imes for stops
on routes using bags were substantially less than on routes using convc ntional containers.
A significance test was performed on the average collection time per stop between
the paired routes in each study area. The difference betwep rhe mean collection time
per stop for all stops on each paired route as indicated in Table 12 was significant at the
5 percent level. The differences indicate conversion to bags in the three study areas
resulted in average time savings per collection stop ranging from 17 to 25 percent as
shown in Table 13.
2. Mean Number of Items and Amount of Solid Waste Per Stop. In February
1970, field studies were completed on routes Al and A2, comprised of single family
residences, to compare the number of polyethylene bags used with the number of cans
used by the householder. Data was collected from 222 stops on route A2 and from 250
stops on route Al. At each stop the number and types of containers and the solid waste
weights were recorded. The analysis for each route consisted of determining
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the average quantity of waste per stop; the percentage of stops having containers of a
given type; and the average number of containers per stop. A summary of the results
is presented in Table 14 and in Figures 25 and 26. The average number of bags used
on the sample day (2.36 per stop) was less than the number of bags distributed per
household; this results from seasonal variations in refuse and the use of cans by some
householders.
The average number of items per collection stop in the routes using bags was
compared to the equivalent value for can routes. Tables 15 and 16 summarize the data.
Bag/can relationships are listed in Table 14 and the container distribution study routes
in each area were compared statistically to determine if a significant difference existed
in the mean number of items per stop. Statistical comparisons made between routes Al
and A2, B3 and B4, and C5 and C6 are summarized in Tables 16, 17, 18, and 19. At the
5 percent level, a significant difference in the number of items per stop was found in
areas B and C. When area C data was reduced to reflect items per residential unit the
significant difference remained.
3. Capacity Utilized in Cans and Bags. Additional field studies were con-
ducted in the study areas to determine the capacity utilized in cans and bags. Table
20 summarizes the results. Although the estimated solid waste capacity of the bags was
found to be within 5 percent of the cans, the actual capacity utilized in the bags was
about 20 percent less than in the cans. Only the large liner bags were found to contain
as much solid waste as the cans in which they were used. Since the liners were larger
than the cans, their utilized capacity was lower. The data indicated that if the bags
were filled to capacity, however, they would hold nearly as much solid waste weight
as the cans even though it is easier to compact solid waste in hard containers than in
bags.
4. Collection Time Comparisons Between Polyethylene and Paper Bags.
During the conduct of field time studies, the project engineers observed that it was
easier to collect polyethylene bags than paper bags. The method of closing the
polyethylene bags with a paper covered wire tie provided the collector with a con-
venient handle for grasping the bag. Plate 2A shows a collector loading a polyethy-
lene bag using this handle. In contrast, the paper bags were found to be loosely
closed and therefore they were more difficult to grasp and lift into the truck hopper.
A properly closed paper bag would probably provide a satisfactory hand hold for the
refuse collector.
In the single family residential areas, Al and B4, field data was obtained on
collection time for stops which contained either all polyethylene or all paper bags.
The collection time for each of these stops was noted along with the number of bags
collected at each stop. The average collection times for stops with polyethylene and
paper bags only were calculated individually as a function of the number of items
collected. In area Al a total of 122 stops containing only polyethylene bags was
compared with a total of 307 stops containing only paper bags. In area B4 a total of
179 stops containing only polyethylene bags was compared with a total of 216stops
containing only paper bags. Figures 27 and 28 present the mean collection times
as functions of the number of bags. The time to collect 6 polyethylene bags was
greater than the time to collect 6 paper bags on routes Al and B4 whereas the time
to collect 5 paper bags was greater than for 5 polythylene bags. This appears to
result from the collectors method of picking up bags, although the precise cause is
not known.
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Least squares lines fitted to the paper and plastic bag data on each route indicate
that the collection time averaged about .02 minutes more per bag for paper than for
polyethylene bags. The difference in the collection time between the polyethylene and
the paper bags, while not statistically significant at the 5 percent level, may be attri-
buted to the greater quantities of waste contained in the paper bags. As indicated in
Table 20, with the exception of the polyethylene drawstring beg, paper bags contained
in excess of 10 percent more waste than polyethylene bags as a percent of utilized
capacity.
5. Condominium Time and Motion Studies. Waste collection in the Briarwood
condominium in the City of Inglewood was studied for over four months. On two days,
April 29, 1970, and May 27, 1970, special time and motion studies were made. On
April 29, 1970, the study covered 366 condominium units from which 739 container
items were collected. Of these 366 units, the data from 241 units was sufficiently
complete for time and motion studies. On May 27, 1970, the study covered 430
condominium units from which 764 container items were collected. Of the 739 items
collected on April 29, 1970, 406, or 55 percent, were disposable bags. Of the 764
items collected on May 27, 1970, 466, or 61 percent, were disposable bags. The
collection time on April 29, 1970, averaged 0.35 minutes per condominium unit. The
collection time on May 27, 1970, averaged 0.37 minutes per condominium unit. The
tabulation of the detailed data is presented in Table 21.
B. Environmental and Safety Studies
1. Noise Survey. An important element in the maintenance of an aesthetic
environment is the control of noise. The emptying and replacement of metallic
containers is normally a source of obnoxious noise. The noise occurs when the metallic
containers are struck against the loading hopper of the collection vehicle to dislodge
tightly-packed contents and when the cans and their covers are replaced on concrete,
asphalt or other hard surfaces. Because collection is begun during the early morning
hours, these noises are more noticeable and may result in complaints by residents.
The replacement of conventional metallic containers with disposable bags
eliminates this source of noise. The use of disposable bags has no effect on the noise
resulting from mechanical operation of the collection vehicle and its packing
mechanism. Noise studies on the conventional hard container syc"om were undertaken
in December 1968. The instrument used for measuring sound levels in the field and
laboratory was a B and K sound meter, Type 2203, illustrated in Plate 2C equipped with
an octave band analyzer. Sound level readings were taken of ths following sources:
background environment, collection vehicle motor, packer mechanism, hard containers
being struck against the loading edge of the truck hopper, can placement upon concrete
or asphalt surfaces, and placing covers on cans. Noise readings were taken at four
distances from the truck hopper source: 2, 10, 50, and 100 feet.
The effect of noise upon humans varies with the intensity and frequency of the
noise produced. Instrument manufacturers have devised sound weighting networks
which are incorporated into noise measuring devices to indicate the relative effect of
different intensity levels upon the human ear. The noise intensity is described in terms
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of decibels (db) and frequency is measured in cycles per second. Three weighting
networks termed A, B, and C are commonly used in noise measurement. The A network
response, since it corresponds roughly to the human ear's response to noise, was used
for the field demonstration. The results are tabulated in Table 22.
For many evaluations the precision sound level meter survey results would be
sufficient, particularly if the end use required only weighted sound levels. However,
if two noises give similar meter indications, but sound differently to the human ear,
then an octave band analysis is required to compare these noises, Corrections for
background noise are important and necessary when the sum measurement (source plus
background) is less than 15 db above the background noise levels. All field data has
been adjusted as required for background noise levels.
A second common measure of noise levels, termed the "noise rating number",
was employed. This number is related to the probable hearing annoyance that would
result if a person were exposed to the noise for a given period of time. The "noise
rating number", N, is defined as
where L = octave band sound pressure level in db
and a and b = constants.
The noise rating number was determined by measuring noise levels from a source
in each of three octave bands with center frequencies of 500, 1000, and 2000 cycles
per second which are known to affect the human ear most. The noise rating number
formula was used to calculate the end value for each frequency and the number
assigned to the source was then the highest of the three. A noise rating number equal
to 85 has been used as a safe limit for conservation of hearing, because habitual
exposure to such a noise level for 10 years may be expected to result in a negligible
loss in hearing for an average individual. Values of a and b used in the formula to
determine the noise rating number for the three octave band levels are presented in
Table 23.
Noise rating numbers for the measurements made in the field over distances from
the origin source of 2 ft, 10 ft, and 50 ft are tabulated in Table 24.
In general, the noise produced when containers were struck against the edge of
the truck hopper resulted in the highest noise levels of the sources measured. At the
2-ft distance from the source (representing the approximate position of the collector)
the noise rating numbers were below levels hazardous to the hearing of the waste
collector. The noise associated with the banging of the waste container would be
eliminated if disposable bags were used. For the Ingle wood collection equipment,
some reduction in vehicular noise from the packer and motor mechanisms should also
be accomplished in order to reduce the noise rating number From 88 to below 85.
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A second series of noise measurements was conducted to determine noise levels
associated with dragging and dropping of metal containers and disposable bags on
concrete, asphalt, and grass. Noise measurements were made at a distance of 35 ft
from the source. The containers studied were loaded with 20 Ib of paper waste and
dropped from heights of 2 ft and 3 ft. Sound intensity measurements were made at
frequencies of 500, 1000, and 2000 cycles per second. The respective numbers for
asphalt, listed in Table 25, did not exceed 85. Only asphalt data are presented for
comparative purposes because they produced the highest noise levels although they
were below the safe limit.
The noise levels produced when plastic bags and paper bogs were dropped on
the three surfaces were about equivalent. However, only the noise levels recorded at
the frequencies of 1000 and 2000 cycles per second were discernible over background
noise levels. The test information also indicated that the noise level associated with
dropping and dragging metal containers over all surfaces were far higher than the
respective noise levels created by disposable bags.
2. Fly Studies. A study of fly generation in household solid waste bags at
the City of Inglewood was conducted in cooperation with the Department of Public
Health of the State of California. 8 The following excerpt is taken from the State
report of the study. 10
"Studies in many communities in California . . . have indicated that excessive
numbers of green blow flies (Phoenicia cuprina and Phoenicia sericata) are produced
in refuse containers with once-a-week refuse collection at homes without garbage
grinders . . .
"Green blow flies have a life cycle that is well suited to once-a-week refuse
collection. The adult female enters the refuse container and lays 50 to 200 eggs. In
warm weather these eggs hatch in the refuse container for four or five days. They then
crawl out of the refuse container in order to enter the pupal stage in the soi1 About
ten days later the adults emerge from the pupae and start another generaticr of flies.
Once-a-week refuse collection allows many larvae to crawl out of refuc- containers
before the refuse is collected . . .
"The data obtained during this study demonstrate that the, existing once-a-week
refuse collection in the City of Inglewood is not adequate to prevent the production
of green blow flies. The use of polyethylene liners in the containers did not
substantially reduce the magnitude of fly production. Analysis of the data, based on
the total number of larvae collected and the number of containers with or without
polyethylene liners . . . the amount of fly production was not reduced enough by use
of the polyethylene liners to warrant their recommendation for fly prevention."
Numerical data on the number of larvae migrating from solid waste containers
is presented in Tables 26 and 27. ™ The data is quite variable, both from container to
container and from week to week from the same container. Frequently a few containers
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with high fly production accounted for a high proportion of the total fly production
in a given week. The old dirty cans that contained the polyethylene bag liners
probably functioned as a major fly source. Fly control would be assisted by using
containers with open bottoms to hold the liners.
Bactericides and odorous animal repellents were investigated for use on
conventional containers and impregnation of bag materials. Oily one bag manufacturer
contacted, Mobil, supplied a bag impregnated with animal repel Ian t, the Mobil
Keepaway. Bag failures due to animal damage were generally reported less often for
polyethylene than for paper bags; no consistent difference in animal damage was
reported, however, on Questionnaires 2, 3, and 4 between the Mobil Keepaway and
other polyethylene bags (see Tables 46, 47, and 50) and paper bags. The use of the
bactericides and odorizers was found to be impractical for cans, and of no discernible
usefulness for reducing bag failures caused by animal damage.
3. Litter Index Studies. Five series of observations were made on selected
streets in the City of Inglewood to determine the extent of littering. On each selected
street, a 1,000 sq ft area, 200 ft long and 5 ft wide, as illustrated in Figure 29, was
observed. The litter items in such area were collected, identified, and dimensionally
measured. Thirty-six streets were observed, located in the demonstration areas B3,
B4, C5, C6, and the Briarwood condominium.
A "litter index" was defined as the sum of surface areas (one side only) of all
readily visible pieces of litter in a 1,000 sq ft test area. A tabulation of these indices,
together with their respective streets, is given in Table 28; the test areas may be
located in Figures 3, 4, and 5.
The litter found in areas using bags and cans is presented in Table 29. The
mean litter index for the can route* was 71.6 which was almost double the 40.3 index
for the bag routes. The average number of items for the bag routes was 4.1 and for can
routes 6.1 .
The litter index ranged from 0 to 244.8 sq in. of litter surface per 1,000 sq ft
of ground area. The mean value was 46.0. The litter index in the Briarwood
condominium area, 1 sq in. per 1,000 sq ft, was significantly less than that in the other
areas, with four of the six test locations having no litter at all. Excluding the Briarwood
condominium area, the average litter index was about 55. The individual litter most
frequently found were paper, match books, cigarette packs, facial tissues, and candy
and gum wrappers. Plate 2D shows a typical collection of litter. Litter was observed
immediately after solid waste collection in four test areas. The collectors usually
cleaned up litter they deposited.
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The distribution of litter item surface area (one side) is shown in Figure 30.
It was found that the greatest number of litter items had surface areas in the ranges
of 2 to 3 sq in and 10 to 20 sq in. The distribution of litter by maximum dimension
is shown in Figure 31 . The greatest number of litter items had maximum dimensions
ranging from 1 to 5 in.
Eight observations were made for container spills at collection stops. On
can routes a total of 51 spills were observed which amounted to 3.5 percent of 1 ,457
stops surveyed, and 0.9 percent of the 5,427 cans observed. A total of 11 spills were
observed on bag routes which amounted to 2 .39 percent of 461 stops and 1 .2 percent
of 919 bags observed. Bag closure ties were used on 61 .8 percent of the bags observed
on all three bag routes. On the three can routes, 41 .5 percent of the cans observed
were covered.
4. Safety . The hazards encountered in carrying heavy containers and
when stepping onto or off of collection trucks are reflected in the results of a California
study^ which indicated that one in every two lost-time injuries reported in solid waste
collection work was due to strain, sprain, or dislocation. In comparison, only about
one-third of all reported disabling injuries in California industries, taken as a group,
were attributed to strains, sprains, or dislocations.
Back strains represented the leading type of injury reportedly sustained by
waste collectors; they accounted for about one-fourth of the injuries recorded.
Sprained ankles were also recorded more frequently for waste collectors than for industrial
workers as a group. Cuts, lacerations, and punctures accounted for 14 percent of
collectors' lost-time injuries; this percentage was somewhat less than that of other
industrial workers. The use of heavy duty work gloves has helped reduce this type of
injury to waste collectors.
More than half of the lost-time injuries occurring in waste collection during
the six month period studied in 1967 resulted from handling metal or other nard cans.
Two out of every three lost-time strains or sprains in collection (including most injuries
to the workers backs, necks or trunks) occurred while handling cans. Frequently the
employee strained and injured himself when he made a sudden or awkward movement
to avoid dropping a can or in attempting to push or pull a can rhat was unexpectedly
heavy or too unwieldy to be lifted by one man without assistance. About 43 percent
of all slips and falls during collection occurred when the injured employee handled a
can. Workers frequently slipped when lifting cans for emptying into the truck or into
the collector 's carry can. Some workers slipped or fell while carrying cans down wet
or littered walk-ways, or they tripped over sprinkler heads.
Collectors occassionally dropped carry-cans or householder's cans on their
feet or caught their fingers on the jagged edges of metal waste cans. Safety precautions
to protect feet and hands should be stressed. Some of the hazards faced by waste
collectors arise from the following: sharp objects placed in containers;
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loose broken glass; chunks of concrete or other heavy objects covered with paper or
other trash; garden hoses or other impediments strewn along the pathway to the can;
and defective rusted cans with unserviceable handles.
During the conduct of the two-year demonstration stud/, no injuries to
collectors were reported as a result of bag handling on the bag demonstration routes.
Two injuries to collectors were recorded during the same time, however, on the
conventional container (can) routes; one sprained shoulder and one cut hand. Disposable
bags can significantly reduce work hazards for the collector because of the following
characteristics:
a) Bags have a limited weight load capacity. Unless very carefully loaded
and handled by the householder, bags containing more than 40 to 50 Ib weight would
be unlikely.
b) Conventional metal containers add materially to the total weight-
handled by the collector. Table 10 indicates that typical galvanized metal cans of
the 32 to 40 gal size have a tare weight between 8 to 12 Ib each. This represents
about 1/3 of the average total weight of a can plus contents.
c) Jagged edges of metal containers would be eliminated.
d) Dust particles and pathogenic organisms in the air would be reduced.
e) Noise levels are lower.
Detrimental effects of bags are that they provide little protection for the
collector from sharp waste objects such as broken glass, or rose bushes. Occasionally,
during the vehicle compaction cycle, tightly-packed polyethylene bags may explode
and scatter contents onto the collector.
C. Handling and Disposal Operations
1. Effects of Polyethylene Bags on Landfill Procedures. The solid waste
from the City ot Inglewood is delivered for disposal to the Los Angeles County Sanitation
Districts' Mission Canyon Landfill. In 1970, the landfill reportedly handled a total of
approximately 5,000 tons of waste each day. About 175 tons per day originated in the
Inglewood municipal system.
An interview sheet (Appendix E6) was distributed to field operators at the
Mission Canyon Landfill Site. Responses from four operators ot crawler tractors on site
and comments from the foreman in charge of the landfill operations were noted; these
responses and comments were concerned with operating problems which arose due to
the disposal of solid waste contained in polyethylene bags.
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The results indicated that polyethylene bags improved operations at the
landfill disposal site. Three of the four field operators reported better pushing of the
solid waste, and two reported on improvement in the spreading operations; in the
case of landfill compaction of solid waste, the operators reported that the bags had
no effect. From an environmental standpoint, all operators reported reduced blowing
of solid waste and dust, while two operators also indicated a reduction in odor.
Discussions with the Landfill foreman indicated that the polyethylene bags
have caused some problems during rainy weather when the bags tended to lodge
between crawler tracks and the frame of the bulldozer. It was also indicated that the
bags made smooth grading on the final landfill solid waste compaction at the fill site
more difficult. As indicated by the operators, the foreman reported bags of solid waste
were more easily handled by a bulldozer than the unbagged wastes.
2 . Polyethylene and Paper Bog Bio-Degradation Effects. In common with
many plastic materials, polyethylene is not readily bio-degradable, and its disposal
in sanitary landfills does not result in rapid alteration of its physical properties.
Therefore, the effect of widespread use of polyethylene bags as solid waste containers
on the proportion of plastic in present day solid waste was considered.
The ratio by wet weight of an empty polyethylene bag to its weight when
filled with waste was on average less than one percent. This may be compared to the
total of two percent by wet weight of plastic material generally present in domestic
waste. Polyethylene bags would, therefore, increase the amount of plastics in domestic
solid waste about 50 percent by wet weight. Domestic waste normally comprises less
than one-third by weight of all solid waste generated, with the remainder generated
from commercial and industrial sources. The contribution of polyethylene bags to the
total wet weight of solid waste in a landfill, therefore, would be less than one-third
of one percent. The total effect of polyethylene bags on pollution problems at disposal
sites would be negligible since their non-biodegradable nature would producs no
contribution to groundwater pollution. The combustion by-products from polyethylene
are carbon dioxide and water, which should not cause significant air pollution.
Paper bags treated with waterproof resins may temporarily iesist bio-degradation
but would have little total environmental impact on landfill o>. incineration disposal.
3. Effects of Disposable Bags on Transfer Station Operations. During one
period of the two-year demonstration program, collection trucks were diverted to a
nearby waste transfer station. The transfer station was of the raised ramp type v/herein
collection trucks dumped their loads from a higher elevation into a large receiving
transfer trailer parked at a lower elevation. Because of the short test period, no
quantitative measurements were made; however, staff project engineers qualitatively
observed that the waste transfer station operations were generally improved. There
were reductions in dust and blowing litter resulting from the transfer of the bagged waste,
even though many of the polyethylene and paper bags were ripped during the compaction
and unloading processes.
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Visual comparisons of the volume occupied by the bagged and normal solid
waste in the transfer trailers indicated there were no substantial differences.
4. Effects of Disposable Bags on Packer-Type Collection Vehicle
Waste Density
The number of collection vehicle loads (trips to landfill) collected per day
and packer vehicle densities were obtained from all three routes before and after bag
distribution. The number of vehicle loads collected on bag routes versus can routes
is given in Table 72. Generally one or slightly more than one truck load was
collected each day on each route. The densities achieved by the packer vehicles
for bag and can routes are given in Table 72. No significant differences in packer
vehicle waste densities were found at the 2.5 percent level.
D. Field Demonstration of Liners for Large Containers
A limited number of 2 mil polyethylene liners were specially fabricated for
testing in waste bins of 2 cu yd and 3 cu yd capacity. These liners were distributed
for a period of three months to some 21 restaurants located in Inglewood and serviced
by contracted private waste collectors. The locations of the demonstration restaurants
are shown in Figure 32. The restaurant bins were cleaned, or replaced if deteriorated,
prior to using-the liners.
A field survey was made of a number of these restaurants to investigate the
major problems encountered in using the liners. The information gathered by the field
survey team was used to draw up a questionnaire which was distributed at the end of
the three month period to all the restaurants taking part in the demonstration. A copy
of this questionnaire is included as Appendix E7. A time and motion study was made
to determine the effects on collection time resulting from using bin liners.
1 . Results of Field Survey. The major problems reported by the restaurants
testing the bin liners were as to I lows: (1) four users stated the liner sometimes slipped
off the bin lip and collapsed; (2) one user indicated that the liner often did not fall out
of the bin when it was emptied; and (3) one commented that the liner was troublesome
to handle. Plate 2B shows a bin with a liner which had slipped off the bin. One user
tied the liner comers to the bin to keep it in position. One reason the liners did not
hold well to the bin rim was that the bin lid hinges normally ran the entire side length
of the bin, thus eliminating this lip for gripping. Three users stated that no problems
were encountered. The positive results reported with bin liner usage were: (1) the bins
were cleaner; (2) odors were reduced; and (3) flies were reduced.
2. Results of Bin Liner Questionnaire. A summary of the questionnaire
responses is given in Table 30; additional comments are given in Table 31 . The results,
of the questionnaire substantiated the findings of the field survey. Improvements were
noted in fly and odor problems and a particular improvement was noted in bin cleanliness,
which would result in a reduction in frequency of bin cleaning. Six of the fourteen
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respondents reported difficulty in installing the liners. Comments made by the
respondents indicated this was due to the liners being too small, although it seems more
probable this was due to non-uniformity of bin size; also, the positioning of lid hinges
on the bin may have contributed to the problem. Other comments received indicated
that two people were needed to install a liner, while one respondent suggested that the
liner installation should be carried out by the collector. The successful reception given
the bin liner system may be directly measured by the unanimous approval of the responding
users and their recommendation for con inued use.
3. Time and Motion Studies of Bin Liner Collection. Field studies were
completed during collection to evaluate bin liner effects on truck pickup efficiency.
The work task movements involving only the liners was timed. The average times for
each task are given in Table 32 for bins with and without liners.
The time required to perform collection tasks with the liner was slightly greater
than the time required to perform the same tasks when liners were not present. Additional
work was required to unhook the liner; this accounted for nearly half the time expended
at a truck loading stop. There were also slightly greater dump and lowering times with
bin liners.
4. Bin Liner Cost Evaluation. Estimates of collection time with and without
liners shows an increase of 0.232 minutes per bin serviced (see Table 32). A cost analysis
for the bin liners is presented in Table 33. The total cost savings attributable to using bin
liners is about $26 per bin per year and results from a reduction in cleaning cost and an
estimated 50 percent increase in the depreciation period. These savings were more than
offset by the cost of the liners ($11 7 per restaurant per year) and the increased collection
time cost $14 per year). These costs do not include the liner installation costs which were
assumed to be absorbed by the restaurants. The net increase in yearly cost of about $105
per restaurant for using the liners does not appear to economically justify their use under
Ingle wood demonstration conditions.
E. Survey of Continued Bag Use
Follow-up surveys were conducted in Study Areas B4 and C5 after ."he demonstra-
tion bags were used up to evaluate public acceptance of polyethylene and paper bags. The
surveys, completed over a six-month period, consisted of monthly counts of residences
voluntarily using bags. The results are presented in Figures 33, °-v, and 35. The use of
paper and polyethylene bags has greatly decreased since the residents had to begin
purchasing their own bags. The 1 .5 mil commercially-available polyethylene bags are
apparently replacing the demonstration's specially-purchased and more expensive 2.5 mil
polyethylene bags. There was little difference in overall bag usage trends at single family
residences or multiple dwelling units (apartment buildings). Bag usage data for apartments
and single unit residences is presented in Figure 35. Apparently, all users discriminated
between bag systems largely on the basis of costs. The total polyethylene bag use trend in
Study Area B4 was downward until July. During June, two major department store chains
began advertising 1 .5 mil polyethylene waste bags in Inglewood newspapers. The residents
evidently responded to the advertising as indicated by the increase in 1 .5 mil polyethylene
bags illustrated in Figure 33. The paper bag use in the same study period and test areas
dropped to less than 5 percent of the total dwelling units.
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VII. PUBLIC HEALTH STUDIES
A. Microbiological and Dust Tests
1 . Parameters. It would be expected that when using bags, dust emission to
the environment would be reduced. The improved sanitary conditions should benefit not
only the total environment but also the waste collector. In order to define the extent
of the dust problem, a study was designed to measure the amount of dust generated
during collection of both bags and cans.
After experimentation with various dust test methods, it appeared that exposing
bacteriological plates containing brain heart infusion agar, an appropriate incubation
media, would be the most suitable method for measuring dust levels. The decision was
based on the assumption that each dust particle would contain some bacteria and that
a colony of bacteria could grow around each incubated dust particle. Incubated
bacterial colony counts would therefore give a measure of the quantity of dust generated
and also allow specific bacteria and fungi to be identified further if desired. Parameters
that were considered when designing the test included the following:
a) Waste collection activity to be sampled.
b) Dust collection bacterial plate exposure time.
c) Point of dust sample collection.
d) Number of dust samples.
e) Background dust conditions.
These parameters and the reasoning behind the study methods are described
below.
a. Waste Collection Activity to be Sampled. The collection activity when
maximum dust generation occurred was selected for critical study. This occurred when
the collector dumped the can waste into the truck hopper. It was also determined that
during this period the collector was exposed to the most dust. In a few instances when
the truck compaction plate used to compress material in the hopper was activated,
polyethylene bags exploded and scattered dust outside of the hopper. The collector
was generally some distance from the hopper when this latter phenomenon occurred.
The critical dust test period occurred when the waste fell from the hard container into
the truck hopper.
b. Dust Collection Bacterial Plate Exposure Time. A 10-second plate
exposure time was selected. Observations in preliminary tests revealed that the
majority of the dust settled within 10 to 15 seconds. Also, 10 seconds allowed
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enough time for the collector to empty one can and yet did not delay normal collection.
c. Point of Dust Sample Collection. Various locations for sampling were
considered, but locating the dust collection plate exposure points near the collector's
face was considered most realistic from the point of health. This location should
provide samples corresponding to the collector's "potential" air breathing. Of course,
the collector would not inhale all the particles caught on the test plates into his
system. The designated collection point was therefore set at the collector's head level,
just to either side to be downwind of the collector, and with the collector standing
next to the truck hopper.
d. Number of Dust Samples. Preliminary tests revealed that about 25 to 30
plate samples were required to get a representative dust fallout count. This was the
basis of the decision to take 30 samples distributed throughout the route of which four
would be background samples.
e. Background Dust Condition. Background sample* were taken at various
times along the collection route with the standard plate exposure time of 10 seconds.
The background sample locations were 15 feet or more away from the waste collection
truck. Care was taken not to take samples during windy periods or other abnormal
test conditions.
2. Field Tests. A series of dust sampling tests was performed on January 7,
1 970 to obtain dust counts during the collection of domestic solid waste from cans.
Some 30 bacteriological dust samples were obtained, four of which were background,
in accordance with the aforementioned procedures. Specific data is tabulated in
Table 34.
Another series of tests was run on January 27, 1970 to determine dust counts
with bags. Again 30 plates were exposed, four of which were background samples.
Only those collection stops at which bags were predominantly used were chosen for the
tests. Specific data is tabulated in Table 35.
Laboratory tests were made on the two sets of samples, as described in Appendix
F.
3. Bacteria and Fungi Counts
a. Cans. Table 36 lists the total number of bacteria and fungi that grew on
brain-heart infusion agar after 24 and 48 hours of incubation at room temperature.
Plate numbers 1 through 30 included those exposed for background conditions (Numbers
1,8, 16, and 30) and those exposed at various times during collecting hard containers
full of domestic waste.
i) 24-Hour Plate Count Results
Bacteria Count. Background samples 1, 8, 16, and 30 had dust counts of 0, 90,
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70, and 0, respectively, which average about 40. The collection vehicle dust test
sample counts ranged from 10 to 1000 per 100 mm diameter plate. The dust count
average for the collection vehicle samples was 164 per 100 mm diameter test plate
as compared to 40 for the background.
Fungi Count. Background samples had no fungi colonies. The collection
vehicle counts ranged from 0 to 800 fungi per 100 mm diameter test plates with all
but one exceeding the background count. The average collection vehicle sample
count was 81 per 100 mm diameter test plate.
ii) 48-Hour Plate Count Results.
Bacteria Count. The four background samples had bacteria counts of 1, 160,
70, and 20 and averaged 63 per 100 mm diameter test plate.
Some of the collection vehicle samples were uncountable due to massive
bacterial growth during the 48 hours incubation. For these samples an extrapolation
was made based on the 24-hour counts and an average growth rate calculated from
the bacterial growth of other known samples.
Collection vehicle 48-hour bacterial sample counts ranged from 15 to 2500
per 100 mm diameter plate (extrapolated). The dust counts of all collection vehicle
samples exceeded the lowest background sample count. Some 73 percent of the
collection vehicle dust counts exceeded the background average, and 46 percent
exceeded the maximum background count. The samples averaged 389 per 100 mm
diameter test plate (including extrapolated values).
Fungi Count. Only one of the four background samples showed fungi colonies
and it had 2, giving an average of 0.5.
Collection vehicle dust sample counts ranged from 0 to 2600 per 100 mm
diameter test plate (extrapolated) with 96 percent exceeding the background values.
The samples averaged 249 per 100 mm diameter test plate (including extrapolated
values).
b. Bags and Liners. Table 37 is a tabulation of a 100 mm diameter test
plate count results. Samples 1,10, 20, and 30 are background samples and the balance
are collection vehicle dust samples.
i) 24-Hour Plate Count Results.
Bacteria Count. No bacteria colonies appeared on background 100 mm diameter
test plates. Regular collection bag work period samples averaged 1 .4 colonies per
100 mm diameter test plate with 12 of 26 plates (or 46.2 percent) containing colonies.
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Fungi Count. No fungi colonies were found on the background samples.
Regular collection bag work period samples averaged 0.15 colonies per 100 mm
diameter test plate. Oily two plates, or 7.7 percent, indicated the presence of
colonies.
ii) 48-Hour Plate Count Results
Bacteria Count. No colonies developed in the background samples. Regular
collection samples averaged 8.1 colonies per 100 mm diameter plate, with 92.3 percent
of the samples having counts exceeding the average background count.
Fungi Count. One colony was counted in the four background samples giving
an average of 0.25 per plate. Collection vehicle samples averaged 21 .7 colonies
per plate. The fungi count of twenty-six samples (or 92.3 percent) exceeded the
average background count.
4. Summary of Microbe Counts. Table 38 is a summary of results for the
plate count studies using cans and bags as waste containers. Microbe counts were
affected little by background conditions; thus for comparison purposes it can be
assumed that the background bacteria counts for cans were the same as for bags, i .e.,
zero at both 24 and 48 hours and wi th the same growth rate as indicated in the first
test series. Under this latter assumption, can values of 124 and 326 bacterial colonies
per 100 mm diameter plate for the 24 and 48-hour counts, respectively, were obtained.
In comparison, 1 .4 and 8.1 bacterial colonies per 100 mm diameter plate for 24 and
48-hour counts, i.e., 98 to 99 percent less bacteria and dust was found with bags when
compared to cans.
Approximately the same reduction was indicated For fungi counts. With cans
the averages of fungi colonies per 100 mm diameter plate were 81 and 249 at 24 and
48 hours, respectively. Counts with bags averaged 0.15 and 21 .7 colonies per plate
at 24 and 48 hours, indicating about 99.8 and 91 .3 percent less fungi with bags. The
comparison of fungi counts is specific since in both test series the fungi background
values were essentially zero. Assuming that the number of microbes which developed
on a media plate exposed to dust is a measure of the quantity of dust in the air at that
point, it was found that a change from cans to bags for waste crp'.ainers reduced dust
generated during waste collection by more than 90 percent.
5. Microbiological Identification. This analysis was concerned with
identification of specific bacterial and fungal types encountered in the dust of
domestic solid wastes, and also with isolating pathogens causing infections and
diseases. No attempt was made to identify the microorganisms in the second series since
it was anticipated that most of them would be the same as those found on the first series;
i ,e., members of the genera Aspergillus, PeniciIlium, Bacillus, and gram negative
bacteria. Due to the relatively low number of colonies on the test plates exposed during
bag collection, the analysis was carried out primarily from the plates exposed during
can collection.
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a. Bacteria. Bacterial colonies on the background plates were of the genus
Bacillus, which are large, gram positive, aerobic, spore-forming rods, and genus
Staphylococcus, which are spherical cluster cells. The only isolated species which is
highly pathogenic is Bacillus anthracia, which is the cause of anthrax; it is hard to
distinguish this from many other species of aerobic, spore-forming bacilli, except on
the basis of pathogenicity. The most commonly encountered saprophytic species were
Bi. subtil is, ji. megaterium, and £. cere us; JJ. subti lis may occasionally cause human
eye infection sometimes complicated by septicimia.
In contrast to the background plates, the test plates showed a wide variety of
fungi and bacteria both chromogenic and achromogenic. The domestic solid waste
samples harbored various pathogenic, morphologically different, viable bacteria, as
can be seen from Table 39 which lists the morphological features and genus of a few
bacteria isolated from representative test plates taken during can collection.
Occurrence of gram positive hemolytic bacteria on test plates indicated the
possible presence of pathogens in the dust samples. These organisms could enter the
body via the respiratory tract, from the dust in the air. Streptococcus and Diplococcus
could cause such respiratory diseases as scarlet fever, septic sore throat, endocarditis,
tonsillitis and lobar pneumonia. Members of the genus Staphylococcus can cause both
localized and systemic infections such as carbuncles, boils, osteomylitis, and septic imia.
The gram negative rods usually appear as relatively large shiny gray colonies
which may or may not be hemolytic. These bacteria are able to grow at low pH, in the
presence of bile, and under anaerobic conditions. Gram negative rods of pathogenic
nature include: Vibrio comma, responsible for cholera; Salmonella, responsible for
typhoid and paratyphoid fevers: and Shigella for bacillary dysentary. Differentiation
of these genera was not made because of the extensive biochemical and immunological
analyses required. A few members of gram negative Protens and Klebsiella are pathogens.
Pseudomonas is generally considered nonpathogenic, but is sometimes found in a
variety of pus-forming conditions, and in some cases it may be the major cause.
Similarly, some strains of Escherichia have significant pathogenicity.
There are many other gram positive and negative, rod-shaped, spore-forming
bacteria which are slow-growing and pathogenic. Such bacteria may have been present
in the dust but did not grow on the test plates because the plates were overcrowded by
other fast growing microorganisms. Examples of such slow growing bacteria are:
Comebacterium, which causes diptheria; Mycobacterium, which causes tuberculosis
and leprosy; Bruce Ha, which causes undulant fever; and Hemophilus, which causes
respiratory infections. A number of these bacteria are known to be present in dust,
plants, and soil, but none were identified during the study.
b. Fungi. Fungi are heterotrophic multicellular members of the plant
kingdom and are referred to as thallophytes. Of about 50,000 species of fungi, only
about 50 are known to cause infectious diseases in man. Some are obligate parasites
on man. Table 40 lists a few genera of fungi encountered during the present investigation.
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Almost all the genera are common saprophytes and are soil inhabitants. The only
exception is Microsporium. This is well known dermatophyte of humans and animals.
Although Aspergilli are among the most common fungus, several strains are pathogenic
and may produce either inflammatory or chronic granulomatous lesions in the bronchi
or lungs, often with hematogenous spread to other organs. Aspergiilus fumigatus is the
species most frequently associated with pathogenic processes. This may include
pulmonary aspergillosis of a severe and invasive type. Phycomycosis is a fatal disease
caused by members of the class Phycomycates, which produce aseptate mycelia and
are ordinarily considered nonpathogenic fungi. The genera involved include Mucor,
Rhizopus, Absedia, and others. The fungus enters the nose of susceptible people,
particularly uncontrolled diabetics and patients receiving prolonged antibiotic,
corticosteroid, or cytotoxic therapy, and penetrates the arteries to produce thrombosis.
Later it invades the veins and lymphatics, producing infarcts. The disease assumes
cerebral and pulmonary forms and, rarely, intestinal, ocular, and disseminated forms.
c . Yeasts. The yeasts are single-celled nucleated microorganisms,
reproducing primarily by budding. In the vast majority of cases, yeasts are considered
to be saprophytic and are used in the wine industry because of their ability to ferment
carbohydrates to alcohol. There are a few yeasts which are pathogenic and cause
chronic diseases in man . Table 41 lists the major diseases caused by yeast-like
microorganisms. Usually infections caused by yeasts are deep-seated systemic diseases.
They are particularly difficult to treat since there are, at present, no really adequate
agents effective against them.
6. Evaluation . The dust generated during collection of domestic solid
waste contains a large number of bacteria and fungi of different genera. Methods to
reduce the efflux of these microorganisms to the atmosphere would benefit both the
collector and the environment. The presence of pathogenic bacteria and fungi is
possible based on the genus families identified, but no pathogenic species were
identified in the samples analyzed. The genus discussed are often present in the type
of dust found in domestic solid waste.
A bibliography on related bacteriological dust studies is presentea in Appendix
G.
B. Laboratory Dust Distribution Study
1 . Objective. The objective of the laboratory dust distrubution study was
to investigate the extent of dust scatter when loading a collection vehicle with solid
waste from can containers.
2. Facilities and Equipment. Facilities and equipment consisted of the
following: a box 2 ft x 2-1/2 ft x 3 ft to simulate a waste hopper on a collection
vehicle; a 40-gallon waste container; simulated waste consisting of 90 percent by wet
weight dust and dirt from a vacuum cleaner; 15-47 mm disposable sample Petri dishes
(Millipore), containing a grid filter paper; a stop watch for timing; and an enclosed
clean room test area.
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Vacuum cleaner dust is the most common type of dust found in domestic solid
waste. The high (90 percent) dust content was used to assure that there would be
sufficient dust to obtain an accurate record of its distribution. The controlled
conditions (windless) were used because it was not feasible to simulate wind
conditions due to their great variability.
3. Procedure. It was assumed that during the solid waste container
emptying operation the dust produced would distribute itself in a pattern with the
center of the hopper as a point of maximum concentration. The pattern of dust
distribution for windless conditions was defined by placing clean Petri dishes with
appropriate filter papers on the floor of an enclosed area at selected distances from
the hopper to catch the dust fallout. The density of collected dust particles were
then determined from four test runs in the laboratory and the results plotted as dust
particle concentration contours.
The tests were completed as follows:
a) All equipment including the solid waste container filled with simulated
waste was taken to the clean room test area where an essentially windless condition
was maintained.
b) The solid waste "hopper" box was placed at the desired dumping location
and level.
c) Fifteen covered Petri dishes were placed radially from the center of
the hopper for each test run. One set of five Petri dishes was placed in line with
the dumping direction on the opposite side of the hopper. Another line of five dishes
was placed at a 45°angle from the first line and the remaining five dishes were placed
90°from the first. Hence, coverage was obtained for the quadrant of a circle with
the hopper as the center. Plates were placed at 3 ft, 4-1/2 ft, 6 ft, 9 ft, and 12 ft
from the hopper center on each radius line.
d) Prior to dumping the can container, the Petri dish covers were removed
and numbers assigned each dish to define its position.
e) The can was emptied so that the solid waste was dumped into the
"hopper" box.
f) The resulting dust was allowed to settle for 2 minutes and then the Petri
dishes were re-covered.
g) The Petri dish samples were then taken to the laboratory and the number
of dust particles per square inch determined using a 50X microscope. Only individual
particles were counted and no differentiation was made as to particle size. The
particle density was calculated for several (3 to 10) grid areas of each plate and
averaged to get an overall plate density in particles per square inch.
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h) The dust concentrations at each Petri dish location were then plotted
on a map of the laboratory test area. Dust concentration contours were drawn by
connecting points of equal particle concentration constructed by interpolation of
particle counts at each Petri dish location along the three radii.
4. Results. Figure 36 is a plot of dust concentration contours for the waste
can collection simulation. The entire pattern was skewed along the direction of
dumping. An area of maximum concentration was located 4-1/2 feet from the hopper
center in the direction of dumping. This high density dust area was in addition to
the hopper area directly under the dumped waste. Dust concentrations ranged from
77,500 particles per square inch at 4-1/2 feet to 500 particles per square inch at
a distance of about 13-1/2 feet from the center of the hopper in the direction of
dumping. Ninety degrees to the right of the dumping direction at about 1 0-1/2 feet
from the hopper center, a level of 500 particles per square inch was observed.
It is interesting to note that the dust concentration drops off between point M
and point D (Figure 36). This was probably due to the shielding effect of the hopper
sides which intercepted the dust particles.
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VIII. QUESTIONNAIRES
A. Distribution of Questionnaires
The questionnai re survey covered bags and ho Iders avai (able from manufacturing during
the years 1969 and 1970. The questionnaire tabulations present relative comparisons be-
tween two or three bag systems used by any one household. The summary compares the
overall results in relative terms and is not to be construed as an absolute rating comparison,
I. Questionnaire I (Pretest Questionnaire). To evaluate citizen interest in
bags, public opinion surveys were undertaken prior to the demonstration tests. Informa-
tion was sought regarding the expressed needs of the public in waste collection service.
The questionnaire was pretested by personal interviews prior to being distributed to resi-
dents in the three study areas in 1968. It was designed to permit the resident to indicate
his level of satisfaction with the pre-demonstration collection system in Inglewood, and
also where emphasis should be placed in making desired improvements. A copy of the
pretest questionnaire is included as Appendix El.
2. Questionnaire 2. During the first bag distribution, the following five bag
systems were studied in the field to determine public acceptance and use characteristics:
a) Mobil Keepaway and Friedman Narrow Polyethylene Bags (2.5 mil) with
Holders,
b) St. Regis Paper Bag with Holder,
c) International Gar box Paper Bag with Holder,
d) Friedman Wide Polyethylene Can Liner (3.0 mil), and
e) St. Regis Paper Bag without Holder (free-standing).
Following 3 months of field use, Questionnaire 2 was mailed to the users in
Areas Al, B4, and C5 to evaluate their experiences with the bag systems. A copy of
this questionnaire is presented as Appendix E2. The number of questionnaires returned,
classified according to bag system and residence type, are presented in Table 42. Due
to the similarity in the dimensional and physical properties of the Mobile Keepaway and
Friedman Narrow polyethylene bags, all responses to Questionnaire 2 were notated as
the Mobil Keepaway bag, and any results obtained on the performance of the Mobil
Keepaway bag may be taken as to also apply to the Friedman Narrow bag.
3. Questionnaire 3. In July 1969, a second bag system distribution was made
so that Areas B4 and C5 users could make a firsthand comparison of two systems. The
only alterations made in bag type were the use of 3.5 mil Wagner can liners in place
of the 3 mil Friedman Wide can liners and the discontinuation of the Friedman Narrow
bag. Questionnaire 3 was sent out to residents in Areas B4 and C5 after the completion
of the second 3-month test period. A copy of this questionnaire is provided as Appendix
E3. The questionnaire responses, classified according to the bag system utilized, are
presented in Table 43.
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Questionnaires 2 and 3 were similar with the following exceptions: the question
on the difficulty of placing polyethylene liners in cans, and a question on whether the
user found it necessary to continue use of conventional containers, were not repeated
in the second questionnaire. Also, a group of questions to compare one disposable
system to another, and a bagging system preference were added to Questionnaire 3.
Responses to both questionnaires were separated for analysis into two categories; those
from residents in single family homes, and those from apartment dwellers. With each
questionnaire the total response of both single family and multiple family residents
were combined for analysis. A detailed review of Questionnaires 2 and 3 was made
on the basis of these combined responses, except where apartment residents responded
in a significantly different manner than the private residents; in several cases,
apartment residents omitted responses to a particular question. Lists of the responses
to Questionnaires 2 and 3 are presented as Appendix H; Tables HI and H3 are expressed
in number of responses, and Table H2 and H4 are given in percentages of responses.
A combined summary of the results of Questionnaires 1 and 2 is presented later
in the text.
4. Questionnaire 4 (Briarwood Condominium Questionnaire). Three bag
systems were distributed to the residents of Briarwood condominium. The systems tested
were:
a) Mobil Flamegard Polyethylene Bag (2.5 mil) with Holder,
b) St. Regis Paper Bag with Holder, and
c) International Garbax Paper Bag with Holder.
The object of the questionnaire was to obtain further comparisons on the
performance of the bag systems in an area where the bags would be carried to the
collection vehicle by the collector. A copy of this questionnaire is included as
Appendix E4. The Mobil Flamegard bag was essentially the same bag as the Mobil
Keepaway; it had the same thickness (2.5 mil) but a slightly larger capacity.
5. Questionnaire 5 (Fo I low-Up Questionnaire). This questionnaire was
distributed to the residents of Ingle wood in June 1970, three morons after termination
of bag use in Area A, and six months after using various bag systems in Areas B and C.
't was the final householder questionnaire to obtain the overall reactions of the
lesidents to the introduction of the bag systems after they had an opportunity to use
several configurations. A copy of this questionnaire is presented as Appendix E5.
B. Results of Questionnaire 1 (Pretest Questionnaire)
Table 44 summarizes the results from the completed questionnaires. Responses
from 886 residences out of 1,600 questionnaires mailed was more than 55 percent.
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The questionnaire response indicated that changing to a bag system would result
in few apparent benefits. Only 29 percent expressed inconvenience in returning
emptied conventional hard containers from the curb to the household storage locations
and 71 percent indicated this was never inconvenience for them.
Many residents commented on the satisfactory collection service provided by the
City. Over 75 percent of the respondents judged the pre-demonstration system as fair
to excellent. Less than 1 percent indicated service was poor. The remaining 24 percent
of the comments amplified answers to one or more of the questions contained in the
questionnaire. In general, the citizens were satisfied with the pre-demonstration
collection service.
The question may be posed that since the great majority of the area residents were
satisfied with the level of service, why should collection system improvements be made?
The answer relates to public service needs. Unless conditions of sanitation are grossly
inadequate, the public generally becomes accustomed to and accepts existing service
standards. The public is normally unaware of possible higher level service improvements
until they are exposed to them. This probably explains the public acceptance of new
products following trial use and the current practice of vendors mailing free samples of
all types of products to the public for promotional advertising. The influence of news
media and the impact of community leaders, accustomed to achieving higher service
levels, also helps promote general public acceptance for improved solid waste
management.
C. Results of Questionnaires 2 and 3
The questionnaires were analyzed primarily to observe the overall effects of the
use of bags as solid waste containers in place of metal or plastic cans, and secondly to
compare the performance of the five types of bag systems under test. The distribution
of the two questionnaires allowed a determination of both the initial response to the
introduction of the bags as well as direct comparisons to be made between different bag
systems.
The summaries of responses from both questionnaires were combined in Table 45
in order to give the overall reaction to the bag systems. These responses, expressed
as percentages of the number of questionnaires returned, are given in Table 46.
1 . Improvements. The greatest improvement noticed by the respondents was
the impact of the bags on neighborhood appearance both on collection day and during
normal usage; the most popular of the bag systems were the St. Regis paper bag with
holder and the polyethylene liners. In general, it was felt that the bags were far more
attractive than the conventional cans, as illustrated in Plate 3.
A sharp decrease in collection noise and fly problems were reported. Odor
conditions and spillage were also reduced for all the bag systems, with the exception
of the St. Regis paper bag used without a holder; the number distributed of this latter
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type of free-standing bag was relatively low, and therefore the results may not be
representative.
2. Difficulties. The most widespread difficulty encountered with the bags was
in closure, with the Mobil polyethylene bag and St. Regis paper bag without a holder
causing the greatest problem. The field studies indicated that the latter bag tended to
be overfilled, and thus the bag mouth resisted closure.
Some difficulties were reported in mounting the three bag types on holders. The
Mobil bag and holder caused some difficulty when placing solid waste in the bag.
Mobil developed an improved (1970) holder which overcame most of the lid opening
and bag filling problems present in their original 0968) design and this was used in
the Briarwood condominium distribution. Difficulties experienced with the
International and St. Regis holders were negligible. Carrying the bags to the curb
for collection was reported as a problem with the polyethylene liners and to a smaller
extent with the International paper bag; but generally the respondents reported that
transport of the bags was far easier than carrying cans.
Sharp objects were reported as the main cause of failures for the Mobil
polyethylene bag and the can liners. The most common cause of failure for both the
International and St. Regis paper bags was the presence of wet solid waste. Animal
attack caused some failure with all types of bags, especially in the case of the 2.5
mil Mobil polyethylene bag, as did deposition of heavy refuse. Reported failure due
to rough handling was negligible.
The overall success of replacing cans with bags as solid waste disposal
containers was indicated by the total favorable response of 77.8 percent of the
householders who preferred the bag system to conventional containers. The most
popular of the five bag systems used were the polyethylene can liners (86.5 percent
favorable) and the St. Regis bag with holder (82.0 percent favorable).
3. Comments. A summary of questionnaire comments is presented in Table
47. The three characteristics of the bag systems which residents liked tht> most were:
0) cleanliness; (2) not having to carry cans: and (3) better neighborhood appearance.
The three items which the residents disliked the most we*^: 0) difficulty of bag
closure; (2) problems with packing solid waste such as yard trimmings in the bags, i.e.,
compacting branches, shrubbery, and other sharp objects; and (3) bag damage due to
animals. Residents also expressed concern about the cost of bag systems.
4. System Comparisons. Table 48 was derived from the responses to
Questionnaires 1, 2, and 3. The attributes delineated on the left hand column of the
table were those on which residents were requested to indicate preferences. The data
from the questionnaires was converted mathematically to a scale of 0 to 10 with
positive comments being given a maximum value of 10 and negative comments given
a minimum value of 0. For each attribute and each system, two numbers separated by
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a slash are shown in the table. The right-hand number denotes the residents'
comparison of the indicated bag system with the first bag system distributed to them
earlier in the test series. The St. Regis paper bag system was rated highest by the
residents both with respect to cans and other bag systems. However, the differences
in ratings are not great enough to be of significance.
D. Results of Questionnaire 4 (Briarwood Condominium Questionnaire)
The Briarwood questionnaire was similar to Questionnaire 2, which solicited the
householders' reactions to bags as solid waste containers, and compared the performance
of the three types of bags under test.
A summary of the number of responses to the questions is given in Table 49, and
are expressed in percentages in Table 50.
1 . Improvements. The analysis of responses showed that the majority of
Briarwood householders felt that bags resulted in marked improvements in all areas of
solid waste management.
The greatest benefit noted was in appearance; of the 330 residents replying, 226
of them indicated that bags had improved the appearance of the neighborhood on
collection day while 241 of them felt that the bag and holder itself was more
attractive than the conventional refuse container. Of the three types of bags in use,
the Mobil polyethylene and St. Regis paper bags were slightly more popular than
the International paper bag.
A marked reduction in collection noise was observed, and more than 60 percent
of respondents noted a reduction in spillage and odor problems. Overall, 40.6 percent
of the respondents believed there was a reduction in the fly problem. Since the
majority of the residences were fitted with screens on both the doors and the windows,
a reduction in flies may not be noticeable unless the respondents passed near the waste
containers; this may have caused the low response to this question.
2. Bag System Difficulties. The storage of paper bags prior to use was reported
as the greatest difficuIty. Paper bags are far more bulky than an equal number of
polyethylene bags; hence, storage of the latter was simpler. In addition, mounting the
paper bags was reported as more difficult than mounting the polyethylene bags. All
of the bags produced closure problems with the largest number of difficulties reported
with the International paper bag. These closure problems resulted from residents filling
the bags too full. The problem might have been rectified by educational literature or
further experience with the bag's limitations.
Some difficulty was ascribed to placing solid waste in the bags, and these
results correlated with reported difficulties involving operation of the holder lids.
In both ratings, the International paper bag system was reported to have caused the
most difficulty.
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Tipping over of the bag holders was negligible.
The primary causes of bag failure, in the few instances reported, were attributed
to sharp objects being placed in the bags. This was particularly evident with Mobil
polyethylene bags which punctured more easily than the paper bags; this was
corroborated by the polyethylene bag's reportedly higher failure rate from rough
handling. Wet wastes reduced the strength of both the International and St. Regis
paper bags which caused a few failures. Failure due to heavy refuse and animal
damage was reported to be negligible for all bag types.
3. System Acceptance. The individual merits of the three bag types and the
overall success of the system in general was indicated by the 79..4 percent of
respondents who preferred the bag systems to conventional hard containers. The
St. Regis paper bag system, with 82.7 percent favorable response, was the most popular.
The Mobil polyethylene 2.5 mil bag system received 79.3 percent approval, while the
International paper bag system had a rating of 76.1 percent.
4. Comments. The comments made by the respondents are tabulated in
Table 51. The favorable comments indicated a wish to continue with the new system
and a desire for knowledge of where to obtain more bags.
The most common negative comments of the residents were a dislike of additional
expense for bags and a preference for cans or plastic containers over the bags. These
latter comments were probably influenced by the fact that hard plastic containers were
supplied free to people who live in Briarwood.
E. Results of Questionnaire 5 (Follow-Up Questionnaire)
The purpose of the follow-up questionnaire for test areas A, B, and C was
three-fold: (1) to directly compare the popularity of each of the five types of bag
systems after a number of systems had been used consecutively by a householder;
(2) to determine the reactions of the householders to the introduction of bags as solid
waste containers following a period of continued use; and (3) to obtain a rating of
importance on specified bag characteristics on which earlier assessments of bag
performance had been based. The response to the importance ratings indicated that
many people misunderstood this section. The answers fell into two obvious groupings;
one set of responses was related to the importance of the item, and the other responses
were related to the problems with bags. The former set of responses was used in
Chapter X in the formulation of bag evaluation criteria, and the latter responses were
discarded.
Five types of bag systems were studied:
a) Mobil Keepaway and Flamegard Polyethylene (2.5 mil) Bags with Holders;
b) Chase (2.5 mil) Polyethylene Bag with Drawstring;
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c) St. Regis Paper Bag with Holder;
d) International Garbax Paper Bag with Holder; and
e) Mobil Luxri (1.5 mil), Friedman Wide (3.0 mil), and Wagner (3.5 mil)
Polyethylene Can Liners.
The summary of the responses to the questionnaires is given in Table 52. In
general, the follow-up questionnaires corroborated information obtained from
Questionnaires 2 and 3.
1. System Comparison. Analysis of the results indicated that the St. Regis
paper bag and holder system was the most popular of the five bag systems in use, with
59.8 percent of the residents rating it higher than any of the other bag systems they
used. The polyethylene can liners and the Mobil polyethylene bags and holder system
followed with ratings of 41.3 and 41.2 percent, respectively; the International paper
bag and holder system was next with 31.4 percent; and the Chase polyethylene bag
wirh drawstring had the lowest rating of 28.7 percent.
2. System Improvements and Difficulties. The most marked benefit was in the
effect of the bags on neighborhood appearance, both on collection day and during
normal usage, with 81.2 percent of the respondents reporting improvement. Improvements
in spillage problems and collection noise were noted to a lesser extent.
The difficulties which arose in placement and removal of the polyethylene liners
in the cans were minor; only 14.1 percent of the respondents found difficulty installing
the liners, while a slightly greater proportion, 15.3 percent, found difficulty in
removing the liners from the cans when full.
The overall popularity of the bag system as an improved method of solid waste
disposal was shown by 80.2 percent of the respondents who preferred the bag system
to conventional cans.
3. Comments. A wide variety of comments, both appreciative and critical,
were made by the residents; these are listed in Table 53.
The most frequent positive comments made were the wish to continue the bag
system and noticeable improvements in neatness and efficiency of the residence and
community solid waste management.
The most common criticisms of the bag system were: (1) the weakness of the bags,
particularly the polyethylene 1.5 mil can liner and the 2.5 mil bags, and the consequent
tearing when filled with yard waste or from animal attack; (2) difficulty in filling and
closing the bags; and (3) the possibility of extra expense if the bag system were generally
adopted. Failure and rupture rates for 1 .5 mil bags were below the acceptable value
of 65 percent, and tensile strength exceeded the derived bag materials criteria constraints.
(See discussion in Section X.C.I.)
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IX. BAG AND LINER MATERIALS TESTING
A. Objectives
As an alternative to field testing of all candidate systems, the results of
laboratory tests which simulated bag and liner performance were used as a guide for
selection of appropriate bag materials.
A complete knowledge of the behavior of a given bag or liner material
requires investigation of properties under a wide range of simulated field conditions.
The conduct of such exhaustive tests to obtain complete information was beyond the
scope of this study. However, data was obtained on properties that had direct bearing
on the economic value and field serviceability of the particular bag and liner materials.
Discussions with bag manufacturers and a review of the relevant literature showed that
no comparable information was available. The laboratory tests helped develop
material specifications on commercially available bags used for the demonstration.
Similarly, various holder and bag combinations were studied at the project engineer's
laboratory to observe their storage and material handling characteristics. Free-standing
bags and liners were also evaluated prior to initiating the field demonstration work.
The laboratory test objectives were:
1 . To supply information on the potential field service quality of candidate
bags and liners.
2. To develop supplemental information about known bag materials.
3. To measure and compare fundamental physical properties of various
candidate bag and liner materials.
Table 54 presents a description of the basic dimensional properties of the various
bag and liner sample specimens tested.
B. Tests
1 . Tens!le Stress-Strain. Tensile stress-strain properties are fundamental
characteristics of each bag and liner material, and provide the most direct means of
comparing different materials. Thus, knowledge of these properties is essential in any
attempt to predict behavior. All materials tests were conducted in-house on a Dillon
Universal Testing Machine. Standard file grips were used to minimize slippage and uneven
stress distribution. The polyethylene and paper test specimens were prepared as shown
in Figure 37. The specimens were carefully measured and found to have reasonably
uniform thickness.
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A load-elongation plotter attached to the Dillon Universal Testing Machine
was used to record data for the paper specimens because of its sensitivity to the very
small elongations experienced by paper. The eye loop scale measurement of strain is
not accurate enough to measure the strain in paper, and the point where paper begins
to tear is not discernible to the eye. The recorder indicated total cross-head movement
as a function of load, and therefore is not dependant on the location of the tear
(elongation). A rectangular paper specimen was used to obtain as near a uniform
stress distribution as possible in order to approach the true strain. If paper specimens
were prepared in the same shape as the polyethylene specimens, the recorder would
not have indicated the true stress or strain. As illustrated in Figure 38, the recorder
measured strain averaged over the entire length of the specimen and thus indicated the
average strain rather than the maximum which occurs at the specimen center.
Polyethylene specimens were initially the same shape as paper specimens
(see Figure 37), but the stress-strain values obtained from the tensile tests were not
consistent due to specimens tearing at the file grips, and the insufficient range of the
load-elongation recorder on the Dillon Test machine. Since the polyethylene material
exhibited elastic-plastic physical properties, the specimen shape was changed to a
necked-down configuration used for testing other materials with similar physical properties.
The new polyethylene specimen shape (Figure 37) eliminated failure at the file grips
and gave consistent stress-strain relationships. As a result of the specimen shape
failures would occur at the smallest cross-sectional area, therefore standard1 gauge"
marks were placed on the specimen prior to testing as shown in Figure 37.
An eye loop and a metal scale were used to measure the distance between the
gauge marks at increments of loading to determine polyethylene specimen elongation.
At 1/4 Ib load increments, the changes in gauge lengths were computed and divided by
the original gauge lengths to obtain the polyethylene specimen strains. Each load was
divided by the original cross-sectional area to determine the specimen stress for each
strain.
Two tensile test series were conducted. In the first series the polyethylene
and paper specimens were loaded until they failed. Longitudinal and transverse paper
specimens were tested separately for failure loads in the second series; in contrast the
polyethylene samples were loaded to an arbitrary load in the plastic range as determined
by the first test series and then unloaded. Measurements were obtained of the longitudinal
and transverse gauge lengths at arbitrary intervals during loading and unloading. A
minimum of three specimens from each bag were used for each test. The test results are
presented in the stress-strain diagrams shown by Figures 39, 40, and 41 .
Two bin liner samples were tested, one from the 3 cu yd capacity and the other
from the 4 cu yd. The polyethylene bin liner samples were subjected to tensile tests
as discussed above. The results are presented in Figure 42. A significant difference
was noted in directional strength properties for both the 3 cu yd and 4 cu yd bin liner
samples tested. The breaking stress for specimens cut longitudinally with respect to
the fabrication direction was greater than the breaking stress for specimens cut diagonally.
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The breaking stress for specimens cut diagonally was greater than the breaking stress
for specimens cut transversely with respect to the fabrication direction. The maximum
stress for the longitudinal polyethylene bin liner specimens was of the same order as
for the smaller household polyethylene bags (see Figures 39 and 40).
2. Cottonseed and Vegetable Oil Soak. The purpose of the cottonseed
and vegetable oil soak tests was to determine the effects of prolonged exposure to
cottonseed and vegetable oil on bag strength. Tensile loads were applied to specimens
as described above to determine the failure load only. The specimens conformed to
the specifications of Figure 37. Prior to testing, several specimens were allowed to
soak in oil for 24, 48, and 72 hours at room temperature. Three specimens from each
bag were soaked for each time period. Results are presented in Table 55.
3. Water, Milk, and Butter Soak. The purpose of the water, milk, and
butter soak tests was to determine the effects on bag strength from saturation by water,
milk, and butter. Tests to determine the failure loads were conducted in the same
manner as those previously described. Three specimens (as in Figure 37) for each bag
were soaked in each substance for 24 hours prior to testing, in addition, the milk
specimens were allowed to soak for 24 hours at 34°F to simulate cold weather conditions.
The water tests were completed in two parts. In the first part, the specimen
was tested wet after soaking for 24 hours at room temperature. In the second part, the
specimen was allowed to dry at room temperature an additional 24 hours. Table 55
presents the test results.
4. Temperature Exposure. Changes in the failure loads of the bag specimens
due to temperature exposure were investigated. The tests were completed as in all
preceding tensile failure tests, except that the various bag specimens were exposed to
either 110°F or 34°F for 24 hours prior to testing at room temperature. The results,
presented in Table 55, indicate that there were little temperature effects for the paper
or polyethylene specimens. These temperatures are the maximum and minimum levels
expected in the City of Ingle wood, California.
5. Perforation . The perforation tests were designed to investigate the
effects of a punctured hole on specimen strength. Hole diameters of 3/32, 1/8, and
1/4 in. were centered at the intersection of the longitudinal and transverse axes. The
specimens were similar to those in Figure 37, and were tensile loaded until failure, as
previously described. Table 55 presents the results and indicates the polyethylene
samples had a smaller marginal percentage strength loss with increasing perforation hole
size than did paper samples.
6. Pinhole. Several small initial punctures may alter the strength
characteristics of a bag significantly, and these tests were designed to investigate this
possibility.
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A 3/8 in. diameter circle centered at the intersection of the longitudinal and
transverse axes servedas the locus of a set of 10 pin holes arranged as shown in Figure
43. The tensile failure load was directly dependent on the location and arrangement
of the pin holes. All specimens were loaded until failure occurred. Table 55 presents
the data for the average failure loads.
7. Puncture. A bag may be punctured by the sharp comer of a box, a nail,
a piece of broken glass or similar items. Puncture tests replicated and measured the
resistance of bags to such failures. Puncture tests were conducted in-house on a
Dillon Universal Testing Machine using a specially devised compression cage. Three
series of tests using probes 1/8, 1/4, and 1/2 in. in diameter ware run on specimens
from each type of bag. The failure load was recorded for each test (see Table 55).
For the 1/8 and 1/4 in. diameter probes, the specimens were clamped over the end of
a one-inch diameter metal tube (see Figure 44) centered directly below the probe in
the compression cage. The 1/2 in. probe was used with a 1-1/2 in. diameter specimen
tube. The tube sizes were chosen so that the specimen would fail at the point where
the probe made contact with the specimen and not along the edges of the tube. As
shown in Table 55, paper bag specimens resisted punctures better than plastic bag
specimens.
8. Creep. The creep tests were undertaken to determine the time rate of
deformation and ultimate strain of plastic specimens under constant loading. No creep
tests were conducted on paper bag specimens because paper is neither a plastic nor
elastic material and therefore does not exhibit creep properties. ASTM Testing Stan-
dards (D674-56, Part 27) note that the test results for plastics are greatly influenced
by material composition and atmospheric conditions of temperature and humidity. Two
tests were conducted: (I) a control test at constant atmospheric conditions and (2)
environmental exposure tests to duplicate climatic field conditions.
A constant 2 Ib dead weight load was applied to each polyethylene specimen.
The 2 Ib weight was chosen to represent a bag load 110 to 140 Ibs (55 inch and 71 inch
circumference, respectively) which is 5 times greater than measured bag weights.
The high load was chosen to represent a concentrated point load such as found from a
pointed object. The dead weight was suspended from a two-inch wide metal paper string
clamp which gripped the specimen evenly, thus minimizing eccentric loading. The con-
trol specimens were placed in a room where temperature could be maintained at a con-
stant level of 74°±2 F; humidity was about constant at 70 percent, and vibration was
essentially negligible. In the environmental weather exposure test, the temperature,
humidity, and possible vibrations were purposely left uncontrolled to simulate field
conditions. Temperatures in sunlight and darkness ranged from 60 to IOO°F over 24
hours and relative humidity varied from 68 to 85 percent.
All specimens were prepared according to the dimensions shown in Figure 37.
The data recorded at the end of each environmental test time interval included the
date, hour, temperature, and the longitudinal and transverse gauge lengths. Initial
gauge marks were set at 1/4 in. length and were measured periodically with an eye
loop and a meta I sea le.
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The total time of exposure For the test was 144 hours; incremental
measurements were taken after: 1/2, 1, 2, 4, 6, 9, 24, 32, 48, 72, and 144 hours
of environmenta('exposure. Table 56 and Figures 45 through 47 describe the results.
9. Moisture Content and Absorption. The moisture content of the paper
bags was determined under laboratory conditions. Representative samples were weighed
and placed in a drying oven at 100°C for 4 hours during which period the weight of
the samples reached a stable condition. The moisture content of each sample was
determined by subtracting the dry weight of each sample from the original weight.
The percent moisture was found by dividing the moisture content by the original sample
weight. Several tests were averaged, giving the following results on a wet weight basis:
West Virginia - 10.3 percent; St. Regis - 9.1 percent; and Bemis - 10.8 percent.
The moisture absorption characteristics of the proper bag materials was also
determined. Sample strips from each bag, approximately 18 in. by 4 in. in dimension,
were weighed and then immersed in water at room temperature for 24, 48, and 72 hours.
The wet samples were then weighed and the amount of water absorbed during each soak
period was calculated. The quantity of water absorbed was found by subtracting the
original weight of the sample material from the wet weight, and was expressed in
percent of water absorbed based on the original weight. The results of the test are
presented in Table 57.
10. Evaporation. Experience in Europe has indicated that a significant
amount of moisture evaporates through a paper bag filled with moist waste materials.
Tests were conducted to determine the percent of moisture lost from wet newsprint
placed inside two paper bags and in one polyethylene bag. Sheets of newsprint were
soaked in water, and then placed inside the test bags. The bags were sealed and
weighed immediately, and after 24, 48, 72 and 96 hours stored at room temperature.
Evaporation was calculated in terms of grams of water lost per sq in. of bag surface.
The results, presented in Table 58, indicate a significant difference between the
evaporation losses from paper bags and those fabricated of polyethylene malarial.
Evaporation of moisture is an advantage if wet waste is placed within the bag, because
a weight reduction would result, thus reducing the work required by the collector.
However, if a paper bag is exposed to a damp environment and dry waste materials are
placed in the paper bag, moisture will be absorbed into the bas Increasing its weight.
11 . Odor. An odor test was performed on paper and polyethylene bag
samples. The test consisted of placing an ammonia solution inside the bags; sealing
the bags; and checking for odor concentration using an odor panel of three previously
trained observers. Odor from the paper test bags was detected from a distance of
5 feet, whereas no odor was detected from the materials placed in the polyethylene
bags. More frequent animal attack would be expected if animals were able to smell
the solid waste contained in a bag. Similarly, insects and vermin may be attracted
more readily to paper bags.
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C. Summary of Test Results
Paper bag specimens cut in the longitudinal direction were 13 to 62 percent
stronger than specimens cut in the transverse direction from the same bag.
Stress-strain diagrams of the polyethylene specimens indicated definite
elastic and plastic ranges. In the case of the paper specimens, the load-elongation
recorder was not sensitive enough to indicate the small variations in length for the low
loading ranges. When elongation was indicated, the fibers of the paper had started to
tear.
Vegetable and cottonseed oil soak tests produced no diminution in the failure
load or maximum loading capabilities of any of the polyethylene specimens tested.
Similar tests on paper specimens showed only minor reductions in their tensile strength
capabilities. The oil soak time period had no significant effect on the failure
characteristics of the specimens.
Butter had a somewhat greater effect than oil on reducing the tensile strength
of paper specimens, but like the oils, did not significantly alter the tensile characteristics
of the polyethylene. Exposure to water and milk generally reduced the maximum
strength of the'paper by 80 percent. When the specimens soaked in water for 24 hours
were allowed to dry for a similar period at 72°F, nearly all the tensile strength
capabilities were regained. The tests also indicated that polyethylene was unaffected
by either milk or water.
Temperature exposure prior to tens! le testing at room temperature did not
significantly alter either polyethylene or paper bag failure loads.
The data from the perforation and puncture tests yielded expected results.
As the perforation hole diameter increased, the failure load decreased. As the
puncture hole diameter increased, the failure load decreased. As the puncture probe
diameter increased, the load required for failure also increased. The polyethylene
puncture resistance for 1/2-in. probes was greater than its tensile failure load. The
paper failure load decreased significantly with larger perforations, whereas the
polyethylene failure loads remained unchanged or decreased slightly. The holes had
a greater effect on paper strength as a percentage of tensile strength, than on polyethylene.
The creep tests indicated that exposure to sun and heat influenced the
maximum strain of the polyethylene specimens. Humidity did not appear to be a major
factor in the creep test results since the range of humidity the environmental specimens
experienced did not vary greatly from the control room humidity. All of the test
specimens exposed to high and low temperatures indicated a higher rate of initial strain
than that of the control test specimens, but after the first 8 hours of exposure time the
environmental and control specimen rates of strain were identical. Creep rates of the
environmental specimens increased during mid-day when the temperature was greatest
and the sun brightest.
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X. FORMULATION OF BAG EVALUATION CRITERIA
A. Approach
The objectives of developing bag system evaluation criteria were threefold:
(1) to establish minimum standards for proposed bag material specifications; (2) to
provide a rationale for comparing bag system performance; and (3) to formulate bag
system selection criteria.
Two approaches were developed for evaluating bag systems; one based on
materials properties and field performance, and the second derived from consumers'
preferences and field performance. The first method consisted of relating the
properties of bag materials to the bag failure rates in the field. The second method
was derived from questionnaire responses from the householders using the bags. The
fibrous composition of the paper bags results in different materials properties than the
plastic nature of the polyethylene bag material. Consequently, they are discussed
separately in the materials property evaluation.
B. Materials Properties
Results from the laboratory tests were used to derive basic properties of the bag
materials. These derived properties were used to investigate corroboration between
laboratory test results and field performance.
Table 59 lists the dimensional characteristics, and Table 60 the physical
properties of the demonstration bags which provide the most significant indices of field
performance. The definitions of technical terms which are not immediately obvious
are described in Appendix A, Glossary. Both paper bags were of two-ply wet strength
construction, and the combined properties of each ply are listed^ Ultimate tensile
strength data is presented for paper bags in both the dry and wet states, since the wet
paper exhibited substantially lower strengths than dry paper. Solid wastes commonly
include liquids and often contain moist materials (see Plate ?E), consequently
realistic evaluations require consideration of the wet-strength properties of the paper
bag. The polyethylene bags were unaffected by water or oils, and consequently only
the results of dry tests are included in Table 60.
1. Polyethylene. The energy absorption potential of polyethylene is an
important measure of the ability of the material to resist puncture and propagation
of tears. Table 63 lists values of strain energy, u*, for specified bag thicknesses;
these values range between 11.8 in.-lb/in.^ and 21.9 in.-lb/in. for polyethylene.
Strain energy, uf is equal to the area under the stress-strain curve which, when
multiplied by the bag thickness, gives u*. A study of this table indicates that all
polyethylene specimens had ultimate stresses of approximately equal magnitude with
no specimen less than 2,000 psi; also a wide range of strain values cu, and
consequently u, are obtainable with the indicated 20 percent variation in stress.
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Thus, for two bags of equal polyethylene film thickness, the one with the higher value
of u should perform best; alternatively, irrespective of bag thickness, a bag with a
higher value of u* should give the better performance.
The existence of a definite relationship between u* and field performance is
substantiated by bag failure rates reported during the field demonstration. Bag
ruptures and failures were counted in areas A,B,and C during the first bag distribution,
and in areas B and C during the second distribution. Figure 48 shows a plot of bag
failures and ruptures versus u*. Skin rupture is defined as punctures and tears, and
does not necessarily imply destruction of waste holding capability; bag failure is
defined as a condition where the contents of the bags are spilled. Thus the ordinate
in Figure 48 is the total percentage of reports of skin ruptures and bag failures combined.
The two data points are shown with an assumed linear relationship connecting them,
which may be expressed mathematically by
F = -2.58 u* + 100 (1)
2
where F = percent failure, and u* is in units of in.-lb/in. .
A third point is provided by assuming that 100 percent failure rate would occur at
zero value of u*; this defines the curve as linear.
Each of the two data points describes two different bags with nearly identical values
of u*, i .e., point 1 combines data for two bags listed in Table 59 (the 30 gal Mobil
Keepaway, and the 33 gal Friedman Narrow bag), while point 2 combines data for two
liners listed in Table 59 (the Friedman Wide and Wagner liners). The data for point 1
is based on data for bags of slightly different capacity used on holders, while data for
point 2 is based on data for bags used as liners. The type of bag support system and
bag/liner capacity could also appreciably influence bag failure and rupture rates.
For example, there is a factor of two difference in the sizes of bags in the data points
with point 1 being based on 30 and 33 gal sizes and point 2 on 60 gal sizes. It seems
logical to anticipate greater failure rates in the larger, more heavily loaded bags. It
is quite possible, therefore, in view of the fact that Figure 48 indicates the opposite
results, that bag size, support, and closure conditions offset each other. The results
indicate, however, that the total available data for the polyethylene bag supports the
hypothesis that u* is a significant measure of structural performance.
It should also be noted at this point that the bag materials test data discussed
previously includes the results of puncture tests. These results are not conclusive, but
do tend to support the hypothesis that u* is an appropriate measure of puncture
resistance; e.g., for two bags of different thickness, the Friedman and Wagner liners,
identical values of u* were obtained, but the failure loads under comparable conditions
were different (see Table 55). The differences in failure loads are, in all cases, less
than the 17 percent difference in thicknesses. The puncture tests, however, were
conducted under ideal conditions; e.g., in an equal biaxial stress field, and thus may
not represent accurate simulation of actual field conditions.
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Both logic and field test experience indicated that it is impractical and
unnecessary to seek a bag which is 100 percent resistant to all rupture. Thus it is
necessary to define those limiting values of u* which give an acceptable rate of bag
failure in the field. A study of Figure 49 and Equation (1) indicate that failures may
be substantially reduced only by increasing thickness of polyethylene bags above
approximately 5 mil. On the other hand, bags for which u*= 10.0 in.-lb/in.? may
not be appreciably inferior to those now in use; i.e., total percent failure may be
75 percent rather than 65 percent.
Since the responses to the demonstration questionnaires indicated that the rate of
failures of the demonstration bags were satisfactory to the householder and collector, it
may be assumed that a minimum value of u*= 10.0 in.-lb/in.2 would give an
acceptable failure rate.
The tensile behavior of the polyethylene bag specimens, shown in Figures 39 and
40, makes it desirable to specify a constraint on the minimum allowable working stress
in addition to a minimum value of u*. This will provide a factor of safety against
thick polyethylene specimens which have acceptable values of u*, but low ultimate
stress au, and a relatively large strain 6U. The test specimens corresponding to a
65 percent failure rate all had values of au equal to or greater than 2,000 psi;
therefore this value was taken as an acceptable minimum.
2. Paper. Two different paper bags, the St. Regis and the International,
were tested, both in the laboratory and the field. Although they were both two-ply
bags, the International bag was constructed with both plys glued together so that they
functioned under load as a single layer. The reported failure rates for both types of
bags were not dramatically different (47 percent for the International single-layer bag,
39 percent for the St. Regis double-layer bag). It seems logical to expect greater
failure in the larger International bag which could be more heavily loaded, and the
reported failure rates seem consistent with this view. Although laboratory and field
test data were available for only two paper bags, the performances noted above once
again appear to be related to strain-energy; i.e., the value of u* for the dry two-layer
St. Regis bag is 2.43 in.-lb/in. , and for the dry single-layer Internaticnal bag is
2.11 in.-lb/in.2. The relative equality of failure rates for the two types of bags may
be a consequence of the similarities in energy absorption capacities.
The test data for the St. Regis two-ply bag indicates that strain-energy for the
wet paper is 58 percent of the dry paper value. Thus it appears (Table 55) that
wet-strength paper bag values of u will generally be about 50 percent of the dry-strength
va I ues.
Since the householders found the rate of failure of the two paper bags acceptable,
it may be assumed that bags satisfying the minimum values of u* (dry) = 2.0 in.-lb/in.^
and u* (wet) = 0.5 u* (dry) would give an acceptable failure rate during service.
The lack of ductility, evident In the tensile behavior of the paper bag specimens
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shown in Figure 42, makes it unnecessary to specify a constraint on the minimum
allowable ultimate stress of the paper material. Values of u* will be more greatly
influenced by ou than by €(J/ and a constraint on u* therefore implies a constraint
on au.
C. Criteria for Bag Selection
The basic parameters which dictate the acceptability of a bag for use as a
container for solid waste are (1) the cost and (2) the strength of a bag with respect
to its failure rate under field conditions. The preceding section has shown that u*
and au are practical measures of resistance to failure during use, and as long as
acceptable minimum requirements for these two quantities are met or exceeded, the
determining factor for bag selection will be the cost. The additional expense of the
bag systems was disliked by many respondents to Questionnaires 2,3, and 5 (Tables
40 and 46). Thus, cost is a valid method for selecting a bag from among several
alternatives which satisfy the materials constraints. The following two sections
present specific criteria for selection of polyethylene and paper bags, respectively,
from this viewpoint. The fundamental differences in material characteristics make
it necessary to treat each category separately.
Although failure rate and cost are undeniably basic parameters affecting bag
performance, and consequently bag selection, it is recognized that many other factors
may influence overall performance, e.g., bag dimensions, ease of closure, type of
holder, etc. Also such aesthetic factors as improvement of neighborhood appearance
may be considered. These other performance factors and householder preferences are
included in a third section which proposes a format for total evaluation of solid waste
bags.
1 . Proposed Criterion for Selection of Polyethylene Bags. Considering the
factors discussed above, the proposed criterion for evaluation or selection of plastic
bags may be simply stated as follows:
minimize: c* (2)
subject to: u* > 10.0 in.-lb/in.2 (3)
ou> 2,000 psi (4)
These constraints will limit the plastic bag failure and rupture rates to less than
65 percent under the field use conditions encountered in Ingle wood. In order to
account for different bag sizes, relative costs are compared; therefore c*, the cost per
unit of bag capacity is used. This quantity is shown in Table 60 for the demonstration
bags.
Inequalities (2 to 4) imply that various "standardized" bag sizes will be compared,
and that only certain discrete combinations of diameter and length are acceptable for
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standard holders.
Thus, for equal values of c*, the preferable material is the one with the highest
value of u*, provided au is no less than 2,000 psi. Alternatively, for equal values of
u*, the bag with the lower relative cost is preferable.
Constraint (3) also defines acceptable values of u for different bag thickness.
The relationship is shown in Figure 49.
2. Proposed Criterion for Selection of Paper Bags. In order to express failure
rate for paper bags as a function of energy absorption capacity, both the dry and wet
state minima must be specified.
A preliminary criterion for selection of paper bags should be based on the fact
that both bags which were tested in the laboratory have proven satisfactory with
respect to rate of failure in field performance. Thus, a selection criterion can be
simply stated as:
minimize: c* (5)
subject to: u* dry > 2.0 in.-lb/in.2 (6)
u* wet > 0.5 u* dry (7)
where u* represents the summation of values for each ply of a multi-ply bag.
The criteria given by inequalities (6) and (7) assumes no inherent structural advantage
of multi-layer bags over single-layer bags.
3. Algorithm Formulation for Total Evaluation of Bag Suitability. The following
factors have all been found significant, to different degrees, when determining the
relative suitabilities of different solid waste demonstration bag systems.
(1) Frequency of bag failure
(2) Ease of closure of filled bag
(3) Ease of mounting bag or liner
(4) Ease of filling bag
(5) Odor control
(6) Frequency of spillage
(7) Frequency and extent of animal damage.
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All of these factors apply to both bags with holders and to liners.
Other factors affecting performance exist and could be included in an expanded
format as they become well-defined. Also, several factors related only to bags or
liners were not included because they are not relevant for comparisons between bags
and liners.
In order to obtain a total preference rating of a bag system, the above factors
may be considered in an algorithm evaluation format as follows:
7
total bag rating fJBR) = £ a.b. (8)
where a; is the rating of a particular bag with respect to each of the seven factors,
and b; is a weighting coefficient for the relative importance of each factor in overall
performance .
Bag ratings, a-, were obtained from algorithm analyses of the residents'
responses to Questionnaires 2,3, and 4, the highest bag rating being arbitrarily
assigned the value of 10. The list of the ratings is presented in Table 61 .
The weighting coefficients, b;, were obtained from the ratings of relative
importance given to the factors 1 through 7 by the respondents to Questionnaire 5;
a summary of the number of responses is given in Table 62, and the corresponding
percentages of the total responses in Table 63. From these percentage ratings the
weighting coefficients, b;, were calculated by arbitrarily assigning values of zero,
one, two, and three to the "none", "very little", "moderate", and "great" percentage
ratings, respectively, and then summing for each factor. The algorithm weighting
coefficient for each factor was then expressed as the quotient of this summation over
the total of all the summations. Thus for each bag system:
7
£ b. = 1.0 (9)
These weighting coefficients are presented in Table 64. A study of these
weighting coefficients indicates the relative importance attached by the residents
to each factor listed; the higher the weighting factor, the more important is the
particular factor to the householder. "Odor control" is suprisingly the most important
single factor listed; the remaining factors are rated as anticipated.
The weighted bag ratings, ajbj, were obtained and are given in Table 65,
together with the total bag ratings for each bag system.
4. Bag System Comparisons. A study of the algorithm results for total bag
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ratings given in Table 65 provides a relative comparison between the demonstration
bag systems.
Both Mobil bags were 2.5 mil bags and, for purposes of this analysis, were
considered as one type of bag since there was no indication of their having any
differences in performance; although the Mobil Keepaway has a smaller capacity,
it did not influence the bag rating.
Table 65 shows that the Mobil system was given the highest total bag
rating of 10.0 by the residents of the Briarwood condominium, thus indicating it to
be the best liked system; the Mobil Keepaway bag, however, previously received a
relatively low total bag rating from the respondents to Questionnaires 2 and 3. The
difference in ratings of these essentially similar bags is due to the different holders used.
Complaints were received from respondents to Questionnaires 2 and 3 about the poor
operation of the original holder lid which subsequently biased the residents' questionnaire
response. The holder design was corrected before distribution to the Briarwood
condominium residents and the resulting higher rating given by respondents to
Questionnaire 4 provides the more reliable result for the Mobil polyethylene bags
and modified holder. This incident illustrates the importance of the total bag system,
including the holder, in obtaining consumer acceptance of bag systems.
Average values of 9.182 for the St. Regis paper bag, end 8.652 For the
International paper bag may be used for comparison since the weighted ratings from
each of the 3 questionnaires do not vary greatly from one another.
The total bag ratings for the two can liners give a similar result; the average of
9.786 may be used for comparison .
The Mobil system of a 2.5 mil polyethylene bag on a holder, and the
polyethylene can liners rate highest in the comparison, followed by the St. Regis
and the International paper bags. The lowest rated bag is the free-standing St. Regis
paper bag, but due to the relatively small quantity distributed and total rating based
on responses to Questionnaire 2 only, the absolute rating value of this last result may
not be directly comparable. The relative ranking, however, is probably accurate.
The sensitivity of the algorithm ratings derived from the responses to the 3
demonstration questionnaires indicate that the format for total evaluation provides an
acceptable rationale for determining the overall suitability of bag systems for field u<
use
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XI. ECONOMIC ANALYSIS
A. System Simulations For Cost Analysis
The impact of disposable solid waste bags on collection efficiency was investigated
by the use of a mathematical model developed by the project engineers. This model
defines the time required for waste collection, and when actual cost data for labor and
equipment are provided, it can be used to estimate collection costs for a particular
service. An IBM 360 computer was used for processing the calculations. Figures 50
through 60 were developed from the computer output to indicate the effects of certain
variables on the efficiency of the waste collection service, and to specifically
determine the influence of bags.
Variables included for the mathematical model simulations were: (1) truck capacity;
(2) quantity of waste at each service stop; (3) time for the collection of a service stop;
(4) travel to the next service stop; (5) the density of waste materials when compacted in
the collection vehicle; (6) the haul time; and (7) the non-productive time of the crew.
The non-productive time includes time spent by the crew for relief, dispatch, lunch, and
for miscellaneous travel. The mathematical model simulates the operations of a single
truck and crew during one day's work activities. Any of the above-mentioned parameters
may be varied independently to determine its effect on waste collection efficiency.
The basic relationship of the model formulation is as follows:
X = ^+B + K + D
where X = the total time to complete a day's work (min);
V = vehicle volumetric capacity (cu yd);
t = mean time per collection stop plus travel time to the next stop (min/stop);
d = mean density of waste in the vehicle (Ib/cu yd);
Q = mean quantity of waste per collection stop (Ib);
B - the one-way average driving time between the route and the disposal
site (min);
K = the total non-productive time (min). Includes dispatch, lunch, relief,
yard to route time, and disposal site to yard time; and
D = the mean disposal time (min/load).
A brief description of the model is given in Appendix I which includes assumptions,
data inputs, and model logic.
On each of the figures the abscissa represents the volumetric capacity of the waste
collection vehicle. The estimated cost data for the collection equipment is presented in
Table 67. The (1969-70) labor cost for Inglewood was $4.80 per hour, including fringe
benefits. For the mathematical model simulation, the mean density of the waste in the
collection vehicle was assumed to be 550 Ib per cu yd. The mean disposal time (D) was
assumed to be constant at 10 minutes per load. The assumed values for the remaining
variables in the above formula are indicated on each of the figures. The abbreviation
(CS) signifies the number of men in the crew including the driver. Figures 50 through 60
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relate to curbside collection of residential waste and represent a'standard 8 hour work day
with 30 minutes maximum overtime. Calculations were made for crew sizes of one, two,
and three men, respectively. Times for two and three man crews were derived from MTM
analyses and the One-Man-Report as described in Appendix I .
The use of disposable bags for waste containers primarily affects only the value
of the time required for collection of the service stop. This time quantity plus the travel
time to the next collection stop is designated as t. Values for t, based on the results of
the two-year study program, were used in the mathematical model to estimate the effect
of disposable containers on the number of services collected per crew; the cost per ton for
waste collection; the man-minutes per ton; and the average cost per service. Table 66,
indicated the values of time, t, in minutes per stop used in the mathematical model
simulations.
lrregularities(nonlinearities)in the total cost,collection time, and number of services
curves are mainly due to the collection of partial loads and the occurrence of overtime.
The return to collect a small partial load, particularly where the haul time, B, is large
may be quite expensive on a unit cost basis. The model restricted partial loads to those
greater than one-eighth of a full load in an attempt to reduce their effect on costs. Waste
collected on overtime costs more per unit of waste than that collected on regular-time.
However, once a truck and crew are on the route collecting waste, if the truck has
remaining capacity to collect an additional quantity, it is more economical to let that
crew continue to collect overtime than to schedule an additional truck and crew for a full
day's operations, unless the additional waste is sufficient to keep the crew active for most
of the day.
Figures 50 through 52 show collection times for bags and cans in man-minutes per
ton as a function of truck volume in cu yd. For these three figures, the values for items
K, B, and Q were assumed as 100, 50, and 60, respectively. Referring to Figures 50
through 52, it is seen that the use of disposable bags reduces collection time. For example,
assuming a truck volume of 25 cu yd, the collection time for a three-man crew is reduced
from 123 to 99 man-minutes per ton,or a reduction of nearly 20 percent over the value
without using disposable bags. For the one- and two-man crews, using a 25 cu yd truck,
collection times are reduced from 53 to 41 and 98 to 76 man-minutes per ton,respectively,
or about 23 percent. Figures 50 and 51 indicate that in the case of the one- and two-man
crew sizes, as the truck volume increases the savings in using disposable bags decreases.
However, in Figure 52, with the three-man crew, the savings increase until a 32 cu yd
truck volume is reached, and then remains constant up to 40 cu yd. These relationships
hold for the values of K, B, and Q indicated. The K, B, and Q values were chosen in
this instance as being representative of verified field conditions encountered in the City
of Inglewood.
Using the same values for K, B, and Q, and for t, the effect of the reductions in
Collection time on average cost per service can be calculated. Figures 53 and 54 illustrate
this effect. From Figure 53 it can be seen for a one-man crew and a 25 cu yd truck, the
savings due to the use of disposable containers were estimated to be approximately 6 cents
per service. This savings would occur each time a stop is serviced (once per week at
Inglewood).
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*This savings does not include the cost of the disposable bags, but represents only the
savings in cost associated with the reduced collection time. Figure 54 indicates that
for the 25 cu yd truck and a two-man crew, a savings in collection cost of about 9 cents
per service would be realized. In the case of the three-man crew, and a 25 cu yd truck,
a savings of about 7 cents per service is indicated. Additional savings from the three-
man crew are realized when trucks with a capacity of 30 cu yd and larger are used. For
example, from Figure 55, if a 32 cu yd truck were used for the three-man crew, the
savings in cost could be 12 cents per service.
Calculations were made to determine the effect of disposable bag use on the
number of services which a collection crew could complete during a normal work day.
For the specified K, B, and Q values, Figure 56 was prepared showing the number of
services collected by the one-man crew assuming the use of conventional containers
and disposable bags. Figure 56 indicates that additional services may be collected by
the crew using the disposable bags. For the 25 cu yd truck, as an example, the number
of services collected per crew can be increased from 325 to 411 . The increase in the
number of services per truck indicates that the area could be collected with fewer trucks
and crews if bags were utilized.
Figure 56 also indicates that a 20 cu yd truck and one-man crew using disposable
bags can collect as many services per day as a 40 cu yd truck using conventional hard
containers. This indicates that for a collection system with a given number of 40 cu yd
trucks handling conventional containers, and with the indicated K, B, and Q values,
the conversion of the entire collection area to disposable bags would permit the
replacement of the 40 cu yd trucks with an equal number of 20 cu yd trucks. The impact
of this change on the cost per ton for waste collection with a one-man crew is indicated
in Figure 57. The cost per ton using conventional containers and 40 cu yd trucks is
approximately $7.10 per ton. The substitution of 20 cu yd trucks for the 40 cu yd trucks
would result in a reduction in the cost to approximately $6.70 per ton. This savings is
due to the decreased capital and operating cost per service. Figure 53 indicated that the
substitution of 20 cu yd trucks and disposable bags for a collection operation using 40 cu yd
and conventional containers can achieve a reduction in cost from 23 cents to 20 cents per
service. Figure 50 presents collection time as a function of truck volume for the one-man
crew; the substitution of a 20 cu yd truck for a 40 cu yd truck is expected to result in an
increase in collection time from 39 to 44 man-minutes per ton. Thus, there is reduced
collection labor efficiency. However, this may be offset by the decreased cost of the
equipment operation and maintenance.
The curves shown in Figure 53 to 55 illustrate the aforementioned cost evaluations,
as well as the practicability of the mathematical model for simulating a known system. Of
course, it is necessary to obtain appropriate field values for a given system and to verify
the applicability of the simulation model. The model can then be employed to determine
savings which may accrue with system improvements such as the use of disposable bags.
The variation of cost per ton, the number of services collected per crew, and the
man-minutes per ton with changes in K, B, and Q has been simulated. Figures 58 to 60
were prepared assuming the City of Inglewood's one-man crew operating with a
conventional container route with one curbside collection per week. Figure 58
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indicates the impact of changing disposal site travel time values from 10 to 30 to 50
minutes on the solid waste cost per service. Because B represents the one-way haul
time (proportional to haul distance), this figure simulates the effect of changing the
location of the disposal site. Figure 59 indicates the effect on Inglewood's cost per
service from changes in the total non-productive work time from 50 to 75 to 100
minutes. It is seen that with a one-man crew system, the non-productive work time
parameter, K, has limited impact on the cost per service. The effect of changing the
average quantity of waste per service stop from 50 to 60 to 70 Ib is indicated in Figure
60. Here again, the sensitivity of the cost per service to changing the average
quantity of the waste per stop is small.
B. Container System Operating Costs
Cost comparisons of can, bag, and container liner systems were completed for
two alternative methods of bag distribution: one where the householder purchases the
bags at private retail outlets; and the second where the solid waste system management
provides distribution of bags and liners directly to the householders. The costs were
calculated for seven alternative container configurations: (I) metal cans; (2) light
duty plastic cans; (3) heavy duty plastic cans; (4) polyethylene liners in metal cans;
(5) polyethylene liners on holders; (6) paper bags on holders; and (7) polyethylene
bags on holders. All containers in the analysis are normalized at 32 gal in capacity.
Dimensional properties of the Mobil 1.5 mil Luxri polyethylene can liner, Mobil
Keepaway 2.5 mil polyethylene bag, and St. Regis paper bag used in the cost
analysis are given in Tables 54 and 60. Collection costs for curb collection, used
in this analysis, were computed using the mathematical simulation model-
A unit cost breakdown for each container system component and related collection
costs are given in Table 68. Cost analyses were made for City (public) distribution
with bags purchased at wholesale prices and public buying of bags and holders at retail
outlets; the data is summarized for the 25 and 35 cu yd capacity collection trucks used
in Inglewood. The costs for City distribution are given in Table 69 and retail purchase
costs in Table 70. The cost of can containers has not been included in the City costs
because they are purchased by residents. The savings in collection system costs
achieved with bags over cans is not great enough to offset the additional cost of the
bags and holders. The least expensive system to residents is the metal con as presently
used; at $19.49 per residence per year retail (Table 70),cans are $1.05 per residence
per year less than the $20.54 polyethylene liner-in-can system. Paper bags are the
most expensive system costing from $26.82 to $32.04 per residence per year for retail
and City distribution. The difference in costs between 25 and 35 cu yd capacity col-
lection trucks ranged from $0.75 to $0.86 per residence per year depending on the
number of containers and system collected. Collection vehicle cost differentials
reflect differences in vehicle costs and capacity.
C. Householders' Economic Benefits
An analysis of intnnrjihle householder benefits associated with the use of bags
-58-
-------
and liners and their effects on collection system costs is given in Table 71. A potential
benefit value of $6.76 was derived from estimated costs of time and materials for clean-
ing cans which would not be accrued with bags and liners. These indirect charge bene-
fits do not accrue to the City, however, and therefore can only be assigned to residents
purchasing cans at retail outlets. When these intangible benefits are considered, the
polyethylene liners and paper bags are less than or equal to, respectively, in cost to
the common metal can system. The householder's response to the demonstration pro-
grams' second through fifth questionnaires were highly favorable to the bag systems,
therefore, the benefits, although intangible in terms of householder's labor, may be
treated as an incentive for using bag systems.
D. Collection System Economics
The costs discussed previously indicated that polyethylene liners in cans would
be the least expensive solid waste container system if public distribution costs are ex-
cluded. There are, however, definite advantages to a City liner distribution system
because the City could maintain standard bag characteristics and cost control through
large quantity contract purchasing. Distribution could be made from public buildings
such as the City Hall, the City Yard, fire stations, etc., and householders would be
billed for liner cost plus distribution cost. The preferred bag distribution method re-
quires a policy decision by the City. The cost of distribution to keep total collection
system costs equal to or less than present can costs should be less than the difference
between can and net liner system costs. This difference can be utilized as a distribu-
tion system decision constraint. For example, the average retail cost difference to
Inglewood householders between the can and liner-in-can system is $2.44 per house-
hold per year; this was derived by averaging the products of the number of each size
truck times the respective can-liner differences. The differences in total collection
costs, $2.68 for the eighteen 35-cu yd trucks and $1.05 for the three 25-cu yd trucks
(Table 70). The cost of distributing bags and liners during the demonstration study
was $4.34 per household per year. The demonstration test distribution costs, however,
were high because the collector's personnel explained the use of the systems to house-
holders during bag and liner distribution. Thus, it appears reasonable to constrain
distribution costs to less than $2.44 per year per household in Inglewood, so that
polyethylene liners in cans would be economically competitive.
Assuming that liners would be distributed to each household quarterly, the
approximately 29,660 household and apartment stops would be served every 13 weeks,
for about 457 stops each day, or 57 stops each hour on the average. For example, if
the equivalent of two full-time employees at $12,000 per year in wages and 125 per-
cent overhead, general and administrative costs could handle distribution of the liners,
the cost would be $27,000 per year or $0.75 per year per household (36,000 households),
This estimated distribution cost falls within the constraint and would result in a
total net yearly cost to householders of $18.58 for the City collection system per house-
hold serviced per year. This cost is competitive with the total household cost of $19.49
per year for the present system when the cost of cans is included.
-59-
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E. Incentives for Use of Bag Systems
Other cities have reported that distribution of bags to residents was a major de-
terrent to their use. Experience has shown, as have the results of the questionnaire
survey previously discussed, that the public is reluctant to accept a change in service
if additional cost is involved. Once the public has used bags, however, they indicate
a preference for bag systems if little or no increase in cost is involved. The results of
the bag use follow-up survey in Inglewood indicated that most householders generally
did not continue to use bags after their free supply was depleted. Those that continued
using bags bought the least expensive bag, the 1.5 mil polyethylene bag and liner.
The major difficulty to surmount in developing an incentive program to promote
the use of bags for solid waste collection is cost. Given cost as a constraint, an incen-
tive program for bag use could be developed along one or more of the following lines:
I. The residents have already invested in cans. This investment can be
preserved by using polyethylene can liners which are also the least expensive of the
bags and liner systems. Neither the City nor the residents would therefore incur addi-
tional costs for holders during the introduction of a City-wide bag system.
2. The City could purchase and distribute liners to residents. The collection
cost savings could be used in either of the following two ways:
a. Collection fees remain the same but liner purchase and distribution
cost is offset by the saving in collection cost attributable to using liners.
b. Collection fees are reduced by the amount of collection cost savings
attributable to liner use. Liner and distribution costs are billed separately; residents
pay the full cost of liners plus distribution.
The best approach would be alternative 2.b, which separates the two costs so
that collection savings can be emphasized. Residents can also be given the alterna-
tive to purchase liners or bags at retail and still have their collection fees reduced.
Other methods of utilizing collection cost savings such as building a transfer station
and changing collection vehicle capacities are not economically feasible at present
(1970) for Inglewood.
Incentives for using liners (or bags) should emphasize: collection cost savings;
reductions in noise, litter, odors, spilled containers, and fly larvae production; a
general improvement in neighborhood appearance resulting from the absence of empty
cans at the curb following collection; and the elimination of the task of carrying
empty cans from the curb to the yard.
Incentives for residents using their cans as holders are the savings in time and
materials expense for cleaning cans, and longer can life when a "protective" liner is
used. Residents would be requested to clean their cans thoroughly prior to using them
as holders to realize the full benefits of the system.
-60-
-------
In order to improve acceptance, the introduction of a bag or liner system would
have to include an educational program to stress the incentives. The residents should
be given the alternative of purchasing bags, liners or holders on their own while
stressing that the City could supply them at lower cost.
A City ordinance specifying standardized bags and liners for use would be
helpful if instituted concurrent with their introduction. Residents would feel more
inclined to cooperate if they knew their neighbors also had to comply.
Other collection system configurations can be formulated to take advantage of
the curb collection cost savings projected for bags and liners in Inglewood. Detailed
mathematical model simulations of various possible collection system configurations
and their related costs would be necessary to finalize a system design. Based on the
requirements of the most suitable system, a recommended plan of action for its
implementation could then be developed.
-61-
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TABLE 1
CLIMATOLOGICAL DATA
Temperature
Month
1968
June
July
Aug.
Sept.
Oct.
Nov.
Dec.
1969
Jan.
Feb.
March
April
May
June
July
Aug.
Sept.
Oct.
Nov.
Dec.
1970
Jan.
Feb.
March
April
May
June
July
a
b
Avg
Max
71.5
73.2
74.1
74.5
72.0
69.7
63.0
62.6
59.6
63.4
66.0
67.8
69.7
73.7
76.7
71.9
73.9
74.1
66.4
63.6
69.5
66.3
67.4
69.9
77.9
85.3
Avg
Min
60.9
63.4
62.9
62.6
58.6
53.7
45.5
51.2
48.2
49.4
54.6
58.4
61.2
64.5
65.3
62.3
58.3
54.4
51.1
50.2
51.8
52.4
51.2
56.7
62.0
65.3
Avg
66.2
68.3
68.5
68.6
65.3
61.7
54.3
56.9
53.9
56.4
60.3
63.1
65.5
69.1
71.0
67.1
66.1
64.3
58.8
56.9
60.7
59.4
59.3
63.3
70.0
75.3
Los Angeles International
•V
F
Highest/Lowest
78/58
80/59
90/59
95/57
94/55
83/43
79/32
82/39
73/42
80/40
81/47
72/50
78/58
79/60
86/60
82/59
88/52
84/44
82/39
73/37
83/46
74/47
82/45
94/51
96/56
96/60
Airport.
Precipitation (in.)
Total
Tb
0.04
T
0.00
0.32
0.24
1.42
9.60
3.76
0.42
0.38
T
T
0.15
0.00
0.01
0.00
1.37
0.01
1.44
1.39
1.29
T
T
0.04
0.00
Greatest
Day
T
0.04
T
0.00
0.13
0.15
0.80
2.63
0.89
0.23
0.24
T
T
0.15
0.00
0.01
0.00
1.26
0.01
0.67
0.66
0.89
T
T
0.04
0.00
Field
Test
Periods
X
X
X
X
X
X
X
X
X
X
X
X
Source: U.S. Department of Commerce.
-62-
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TABLE 2
OPERATING STATISTICS
CITY OF INGLEWOOD COLLECTION OPERATIONS
Year
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970C
Man-Hours
52,170
49,155
49,067
47,842
37,967
39,661
40,846
39,742
36,949
36,533
18,964
Tons
24,220
28,746
30,869
32,388
32,500
34,699
35,208
36,502
35,349
37,529
18,154
Average
Load Size (Tons)
4.14
4.81
4.97
5.65
7.27
7.77
7.75
8.24
8.11
8.66
8.13
Man -Hours
Per Ton
2.19
1.72
1.63
1.48
1.17
1.15
1.16
1.09
1.04
0.97
1.04
, All loads are weighed at the disposal site.
The performance rate was calculated based on paid direct collection labor
hours including supervisory personnel, and tonnage from scale receipts. High
performance rates of about 1.0 man-hours per ton have been of local and national
interest.
January-June, inclusive.
-63-
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TABLE 3
STUDY AREA DESCRIPTION
Study Area
and Route
Al
A2
B3
B4
C5
C6
Total
Tota! Route
Length (mi)
4.2
4.0
5.7
5.4
5.0
6.8
31.1
Single
Fami ly
267
233
314
326
82
106
1,328
Units
Multiple
1
13
0
0
86
80
180
Commercial
0
2
0
0
0
0
2
Total
Stops
268
248
314
326
168
186
1,510
Total
Residential
Units
271
294
314
326
656
550
2,411
-64-
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TABLE 4
INITIAL FIELD SURVEY, CONTAINERS'
Study Area
Route
Week
1
2
3
4
Composite
Total
Stops6
A
1
Meanb S.D.C
2.77 1.19
2.75 1.13
2.68 1.23
2.74 1.25
2.74 1 .20
1,031
B
2
Mean S.D.
2.74 2.87
2.75 1.61
2.72 1 .55
2.82 1 .36
2.75 1.57
921
3
Mean S.D.
N.D.dN.D.
2.74 1.19
2.51 1 .01
2.51 1 .00
2.59 1 .08
897
4
Mean S.D.
3.05 1.56
2.62 0.98
2.53 1.12
2.62 1.05
2.69 1.19
1,031
C
5
Mean S.D.
N.D. N.D.
4.70 2.97
4.33 2.79
3.79 2.65
4.31 2.85
405
6
Mean
4.14
3.17
3.48
3.35
3.49
676
S.D.
1.88
1.66
2.48
2.12
2.38
g
, Cans only. Study was made prior to distributing bags.
Number of cans per stop.
, Standard deviation of the number of cans per stop.
Not determined.
Total collection stops made during study period.
-------
TABLE 5
INITIAL FIELD SURVEY, ITEMS
Study Area
Route
1
2
3
4
Composite
4
b c
Week Mean S.D. Mean S.D. Mean S.D. Mean S.D. Mean S.D. Mean S.D.
3.98
3.98
3.86
3.93
3.94
Total
Stops6 1,031
2.46 3.64 2.50 N.D.d N.D. 3.42 1.80 N.D. N.D. 6.49 4.62
2.60 4.07 2.69 3.66 2.07 3.23 1.68 6.22 4.80 5.83 4.50
2.52 3.76 2.45 3.77 2.30 3.72 2.43 7.04 5.16 5.66 4.55
2.44 4.26 2.49 3.82 2.33 3.73 2.19 6.81 5.48 5.58 4.19
2.51 3.94 2.54 3.75 2.23 3.53 2.07 6.66 5.16 5.85 4.47
921 897 1,031 405 676
• Total items including cans. Study was made prior t<
Number of items per stop.
. Standard deviation of the number of items per stop.
Not determined.
Total collection stops made during study period.
was made prior to distributing bags.
-------
TABLE 6
INITIAL FIELD SURVEY, COLLECTION TIME (MINUTES)
Study Area
Route
Week Mean
1 0.53
1
° S.D.
0.32
2 N.D.C N.D.
3 0.60
Composite 0.57
a
u
D
C
d
Total
Stops0" 516
Minutes per stop
distributing bags
0.38
0.37
A
2
Mean
0.53
0.51
0.71
0.62
692
, includes only actual
.
Standard deviation of the
Not determined.
Total collection
S.D.
0.37
0.40
0.49
0.51
B
3
Mean S.D.
0.54 0.32
0.54 0.34
0.65 0.35
0.58 0.34
897
time at a stop; does not ?
collection time per
stops made during the
initial
stop.
field study period
• •
4
Mean S.D.
TJ*§2 0.29
0.55\ 0.33
\
i
0.57 V0.33
0.55 0.33
849
nclude travel time.
prior to distributing
C
5 6
Mean S.D. Mean
0.82 0.66 0.90
0.90 0.59 0.79
0.94 0.70 0.86
0.88 0.66 0.87
405 535
Study was made prior to
bags.
S.D.
0.64
0.61
0.63
0.65
-------
TABLE 7
INITIAL FIELD SURVEY, TRAVEL TIME BETWEEN STOPS (MINUTES)
Study Area
Route
Week
1
2
O> 0
00 O
4
Composite
Total
Stopsd
1
Mean
0.12
0.10
0.14 .
0.13
0.13
1,031
A
2
S.D.b Mean S.D.
0.16 0.12 0.17
0.13 0.11 0.13
0.15 0.11 0.14
0.15 0.10 0.12
0.18 0.13 0.21
921
3
Mean S.D.
N.D.C N.D.
0.16 0.16
0.13 0.17
0.15 0.15
0.16 0.20
897
B
4
Mean S.D.
0.10 0.12
0.10 0.14
0.10 0.10
0.12 0.13
0.13 0.21
1,031
5
Mean
N.D.
0.21
0.17
0.17
0.20
405
C
6
S.D. Mean
N.D. 0.16
0.23 0.19
0.22 0.18
0.18 0.18
0.26 0.20
676
S.D.
0.20
0.24
0.21
0.19
0.27
, Minutes per stop. Study was made prior to distributing bags.
Standard deviation of the travel time between stops.
, Not determined.
Total collection stops made during study period.
-------
TABLE 8
INITIAL FIELD SURVEY SIGNIFICANCE TEST - TOTAL ITEMS PER STOP
Mean Number of Items
at the Stop
Week
1
2
3
4
Composite
Route Al
3.98
3.98
3.86
3.93
3.94
Route A2
3.64
4.07
3.76
4.26
3.94
Standard Deviation
Route A 1
2.46
2.60
2.52
2.44
2.51
Route A2
2.50
2.69
2.45
2.49
2.54
Significance,
Number of Samples Level, U
Route Al
260
256
255
260
1,031
Route A2
229
222
227
243
921
1.525
-0.376
0.445
-1.516
0.033
, Standard deviation of the number of items per stop. Study was made prior to distributing bags.
Rejection number is + 1.96 at 5% level of significance.
-------
TABLE 9
QUANTITY OF SOLID WASTE PER HOUSEHOLD UNIT*
AREA A
No. Units Collected
Week0
1
2
3
4
Composite (Area A)
Route 1
263
259
258
263
1,043
Route 2
258
248
257
267
1,030
Quantity/Unit (Ibs)
Route 1
71.6
72.2
68.6
65.0
69.3
Route 2
62.6
72.5
58.0
69.5
65.6
AREAB
Week
1
2
3
4
Composite (Area B)
Route 3
N.D.''
300
302
295
897
Route 4
182
296
259
294
1,031
Route 3
N.D.
61.3
61.8
67.6
63.5
Route 4
69.1
62.8
58.5
60.8
62.3
AREAC
Week
1
2
3
4
Composite (Area C)
Route 5
N.D.
568
431
516
1,515
Route 6
457
482
476
486
1,901
Route 5
N.D.
32.0
43.8
33.1
35.8
Route 6
40.2
38.9
39.5
35.3
38.4
Measured during October of 1968.
Field data was obtained From all study routes during each week for once-a-week
collection.
Not determined.
-70-
-------
TABLE 10
SOLID WASTE PHYSICAL DATA SAMPLING*
November 1 968
Area A Area B Area C
Stops Sampled (no.)
Total Sample Wt (Ib)
Avg. Solid Waste/Can (Ibf
Avg. Can Wt (empty) (Ib)
Avg. Item Wt (Ib)
Solid Waste Composition
Class 1 (fibers)
Class 2 (vegetation)
Class 3 (metals)
Class 4 (inerts)
Class 5 (putrescibles)
Moisture Content6
Class 1 (Fibers)
Class 2 (vegetation)
Class 3 (metals)
Class 4 (inerts)
Class 5 (putrescibles)
Organic Content6
Class 1 (fibers)
Class 2 (vegetation)
Class 3 (metals)
Class 4 (inerts)
Class 5 (putrescibles)
17
659.0
15.0
8.5
7.5
46.3
34.3
6.3
10.3
2.8
9.6
137.0
N.D.d
0.9
558.9
84.2
84.2
67.1
N.D.
90.9
73.3
16
797.6
16.5
8.1
8.7
62.2
15.0
7.6
14.2
1.0
6.9
152.0
N.D.
2.8
20.8
38.9
38.9
68.1
N.D.
51.5
89.8
7
572.2
20.6
11.8
8.1
61.3
7.5
8.3
16.8
6.1
4.2
138.5
N.D.
0.4
233.5
88.9
88.9
79.7
N.D.
22.2
79.1
February 1 969
Area A Area Bf Area C
16
1,474.5
20.8
8.1
25.2
58.5
33.3
3.9
3.3
1.0
30.2
134.0
N.D.
0.68
90.7
86.5
86.5
55.7
N.D.
5.9
80.0
13
787.5
20.4
8.6
20.2
57.2
22.7
5.8
13.1
1.2
181.4
117.2
N.D.
0.3
92.2
82.8
82.8
62.9
N.D.
9.7
80.7
7
797.}
23.9
10.4
7.0
64.6
15.3
6.3
12.2
1.6
20.1
155.3
N.D.
19.7
72.5
83.5
83.5
49.3
N.D.
46.6
86.5
July 1969
Area A Area B Area C
17
1 ,499.3
16.7
7.4
21.8
34.7
52.7
2.8
4.5
5.3
76.0
99.7
N.D.
0.38
N.D.
97.6
97.6
66.7
N.D.
8.4
N.D.
15
872.6
20.8
11.5
19.3
28.3
55.0
2.2
6.7
7.8
12.8
127.4
N.D.
0
N.D.
96.7
96.7
66.3
N.D.
8.2
N.D.
14
1,885.5
23.6
10.9
20.1
58.8
12.0
9.4
15.2
4.6
7.0
24.1
N.D.
3.8
N.D.
98.5
98.5
89.7
N.D.
26.7
N.D.
-------
TABLE 10 (Continued)
SOLID WASTE PHYSICAL DATA SAMPLING
Sample size was selected to obtain a 60 percent statistical confidence level,
b Weight of -.solid waste in can, Ibs.
c Percent, Wet Weight.
d Not Determined.
e Percent, Dry Weight.
' Heavy rainfall during and prior to period of sampling.
-72-
-------
TABLE II
PURCHASE SUMMARY
Manufacturer
Distribution Name Model
1 St. Regis
International
Mobil
St. Regis
International
Mobil
Friedman
Friedman
2 St. Regis
International
Mobil
Wagner
3 St. Regis
International
Mobi 1
Chase
Mobil
Bin Liner Bemis
Bern is
PM-40
Garbax Model A
PL9-I302
Handi-Sack
Garbax
Keepaway
Narrow
Wide
Handi-Sack
Garbax
Keepaway
Handi-Sack
Garbax
Flamegard
Drawstring
Luxri liner
2 cu yd
3 cu yd
Material
N.A.a
N.A.
N.A.
Paper
ii
Polyethylene
ii
ii
Paper
ii
Polyethylene
ii
Paper
ii
Polyethylene
11
ii
Polyethylene
n
Thickness
(mil)
N.A.
N.A.
N.A.
N.A.
N.A.
2.5
2.5
3.0
N.A.
N.A.
2.5
3.5
N.A.
N.A.
2.5
2.5
1.5
2.0
2.0
Use
Holder
II
II
Bag
n
n
M
Can Liner
Bag
ii
n
Can Liner
Bag
n
11
n
Can Liner
Bin Liner
n
Total
Purchase Date Number
3/26/69
n
"
n
n
n
n
n
7/1/69
n
n
5/13/69
11/10/69
II
11
II
II
2/2/70
n
200
200
200
15,000
14,000
10,000
6,000
9,000
10,200
10,000
4,400
5,000
10,000
8,000
10,000
14,000
9,600
2,520
3,000
Cost
($)
each
12.00
8.00
8.90
1,000
96763
92.15
69.50
70.49
136.84
96.03
92.15
69.50
129.95
96.03
92.15
94.01
87.36
55.00
347.14
429.42
Not applicable.
-------
TABLE 12
COLLECTION TIME PER STOP
Area
A
B
C
Route
1 (Bags)
1 (Bags)
2 (Cans)
3 (Cans)
4 (Bags)
4 (Bags)
5 (Bags)
5 (Bags)
6 (Cans)
Stops
Sampled (No.)
761 b
979C
465C
81 5C
774b
1,225C
201 b
266C
256C
Mean Collection
Time Per Stop (mln.)
0.353
0.448
0.546
0.621
0.409
0.514
0.648
0.735
0.981
Significance
S.D. Level, U°
0.249
0.368
0.362 -4.79
0.344
0.333
0.421 6.31
0.534
0.616
0.684 -4.32
Rejection number is + 1 .96 at 5% level of significance. U values are for
, all stops.
Bag stops only, Data is compiled from 4 weeks of field studies.
All stops.
-74-
-------
TABLE 13
AVERAGE COLLECTION TIME SAVINGS PER STOP
Area
A
B
C
Mean Collection Time/Stop
(min .)
Bag Route Can Route
0.353°
0.448b 0.546
0.409a
0.514b 0.621
0.648°
0.735b 0.981
Reduction
(min.)
0.193°
0.098b
0.212°
0.107b
0.333s
0.246b
Time Reduction
of Can Route
(percent)
35°
18b
34°
17b
34b
25b
°Stops with bags only.
b
All stops with all items (bags, cans, and other).
NOTE: The collection time given does not include travel time.
-75-
-------
TABLE 14
CONTAINER DATA SUMMARY0
Data on Stops Having Cans or Baas and
Other Items
Stops Sampled (No.)
Average Items/Stop (No.)
Average Cans/Stop (No.)
Average Bags/Stop (No.)
Average Solid Waste Quantity (Ib/stop)
Collection Time on Route (hr)
Ma n -m i n utes/Ton
Average Time/Stop
Data on Stops Having Only Cans or
Only Baps
Route
Stops Sampled (No.)
Average Cans/Stop (No.)
Average Bags/Stop (No.)
Al (Bags)
250
3.89
0.66
2.36
70.1
3.00
20.5
0.72
Al (Bags)
95
N.A.d
2.82
Route
A 2 (Cans)
222
3.23
2.27
0.20
62.8
2.83
24.4
0.765
A2 (Cans)
127
2.44
N.A.
° 2/11/70 data.
On route only.
Collection and travel on route only.
Not applicable.
-76-
-------
TABLE 15
ENVIRONMENTAL SURVEY SUMMARY
Area
Route
Container Type
Date of Survey
Stops Sampled (No.)
Total Polyethylene Bags (No.)
Total Large Paper Bags (No.)
Open Pety ethyl en e Bags (No.)
Open Paper Bags (No.)
Polyethylene Bags Open (%)
Paper Bags Open (%)
Spilled Polyethylene Bags (No.)
Spilled Paper Bags (No.)
Total Cans (No.)
Cans- No Lid (No.)
Cans - No Lid (%)
A
1
Bags
10-21-69
26
47
18
12
8
25.5
44.4
0
0
3
2
66.7
2
Cans
10-28-69
24
4
0
N.A.a
N.A.
N.A.
N.A.
N.A.
N.A.
49
31
63.3
B
3
Cans
10-23-69
25
3
0
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
49
34
69.4
4
Bags
10-16-69
32
54
15
10
11
18.5
73.3
0
0
20
16
80.0
C
5
Bags
10-17-69
13
41
55
7
30
17.1
54.5
0
0
5
5
100.0
6
Cans
10-24-69
21
5
0
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
87
75
86.2
Npt applicable.
-------
TABLE 16
FIELD SURVEYS, SOLID WASTE CONTAINERS (NUMBER)'
Study Area
VJ
00
Route
Week
1
2
3
3
Composite
Total
Samples
a
b
c
d
A
1 (Bags)
Mean
3.77
3.99
4.21
4.35
4.08
979
S.D.C
2.00
2.26
2.30
2.46
2.27
Total items including
Number per stop .
Standard deviation of
B
2 (Cans)
Mean
3.56
4.09
N.D.
4.12
3.93
699
S.D.
1.96
2.12
d N.D.
2.41
2.18
1
cans or bags .
the number of items
3 (Cans)
Mean S.D.
3.87 2.09
3.99 2.16
3.91 2.12
3.87 2.19
3.91 2.14
,166
per stop.
4 (Bags)
Mean
3.96
4.06
4.31
4.21
4.13
1,120
S.D.
2.17
2.20
2.85
2.44
2.43
C
5 (Bags)
Mean S.D.
6.89 5.50
7.21 5.60
7.30 5.65
N.D. N.D.
7.13 5.57
444
6 (Cans)
Mean S .
6.08 3.
5.89 4.
6.29 4.
N.D. N
6.07 4.
468
D.
99
28
88
.D
39
-------
TABLE 17
SIGNIFICANCE TEST - TOTAL ITEMS PER STOP, AREA A
Mean Number oF Items
at the Stop
Week
1
2
3
4
Composite
Route Al
Bags
3.77
3.99
4.21
4.35
4.08
Route A2
Cans
3.56
4.09
N.D.C
4.12
3.93
Standard Deviation
Route Al
Bags
2.00
2.26
2.30
2.46
2.27
Route A2
Cans
1.96
2.12
N.D.
2.41
2.18
Number of Samples
Route Al
Bags
236
249
249
245
979
Route A2
Cans
232
238
N.D.
229
699
Significance
Level, U
1.15
-0.50
N.D.
1.03
1.37
, Standard deviation of the number of times per stop.
Rejection number is + 1 .96 at 5% level of significance.
Not determined.
-------
TABLE 18
SIGNIFICANCE TEST - TOTAL ITEMS PER STOP, AREA B
Mean Number of Items
at the Stop
Week
1
2
3
4
Composite
Route B3
Gins
3.87
3.99
3.91
3.87
3.91
Route B4
Bags
3.96
4.06
4.31
4.21
4.13
Standard
Route B3
Cans
2.09
2.16
2.12
2.19
2.14
Deviation
Route B4
Bags
2.17
2.20
2.85
2.44
2.43
Number of
Route B3
Cans
304
301
300
261
1,166
Samples
Route B4
Bags
289
283
289
259
1,120
Significance
Level, U °
-0.51
-0.39
-1.93
-1.68
-2.295
• Standard deviation of the number of items per stop.
Rejection number is + 1.96 at 5% level of significance.
-------
TABLE 19
SIGNIFICANCE TEST - TOTAL ITEMS PER STOP, AREA C
Mean Number of Items
Per Unit
2
T
Week
1
2
Composite
Route C5
Bags
3.81
3.07
3.39
Route C6
Cans
2.76
2.77
2.76
Standard
Route C5
Bags
3.10
2.24
2.67
Deviation
Route C6
Cans
2.04
2.12
2.08
Number of Samples
Route C5
Bags
141
179
320
Route C6
Cans
147
141
288
Significance
Level, Ub
-3.39
-1.23
-3.27
, Standard deviation of the number of items per unit.
Rejection number is - 1.96 at 5% level of significance.
-------
TABLE 20
FIELD CONTAINER WEIGHTS
Container Type
Paper Bag
Polyethylene Bag
Samples
(No.)
75
74
Full
(Ib)
19.5
15.4
Empty
(Ib)
0.5
0.1
Net
(Ib)
19.1
15.3
Utilized
Capacity"
(%)
79.8
75.3
Estimated Net
Weight of Full
Container (Ib)
23. 9b
20.4
(2.5 mil)
Polyethylene Drawstring
Bagd(2.5mil) 37 14.7 0.1 14.6 88.0 16.6
Polyethylene Can Liner
(1.5 mil) 27 15.1 0.1 15.0 77.6 19.3
Polyethylene Can Liner
(3.0 mil) 58 24.2 0.1 24.1 74.7 32.3
Cans9 197 33.2 9.7 23.5 91.2 25.8
• Thickness not applicable. 35 gal size packed free-hanging.
Estimated net weight of full container = rrrn—. /» ' . • /0/\
0 Utilized Capacity (%)
, 32 gal size packed free-hanging.
20 gal size packed free-hanging.
. 45 gal size liner installed in a 32 gal can and packed as free-hanging.
45 gal size packed free-hanging.
? 32 gal size.
Bag capacities are based on the volume available when the bags are closed.
-82-
-------
TABLE 21
FIELD SURVEY WASTE COLLECTION AT BRIARWOOD CONDOMINIUM,
INGLEWOOD, CALIFORNIA
Item
Number of condominium units
serviced
Number of service stops
Collection time, minutes
Travel time, minutes
Number of items collected
Number of bags collected
Number of paper bags
collected
Number of polyethylene bags
collected
Number of cans collected
Number of boxes collected
Number of bundles collected
Number of sacks collected
Number of paper bags on
holders
Number of polyethylene bags
on holders
Lost time, minutes
April 29, 1970
366°
195
83.5
26.7
739
406
N.D.b
N.D.
165
69
28
71
N.D.
N.D.
7.01
May 27, 1970
430
315
157.7
46.3
764
466
324
142
182
46
30
40
36
9
22.1
Continued . . .
-83-
-------
TABLE 21 (Continued)
FIELD SURVEY WASTE COLLECTION AT BRIARWOOD CONDOMINIUM,
INGLEWOOD, CALIFORNIA
Item
Number of spills
Average number of condominium
units collected per stop
Average number of items
collected per stop
Average number of items
per condominium unit
Average collection time per
stop, minutes
Average collection time per
condominium unit, minutes
Average travel time per stop,
minutes
Average travel time per unit
collected, minutes
April 29, 1970
N.D.
1.88
3.79
2.02
.430°
.346°
.137
.111
May 27, 1970
7
1.37
2.42
1.77
.500
.366
.147
.108
, Of this total, 241 units were used to determine collection times.
Not determined.
-84-
-------
TABLE 22
SOUND MEASUREMENTS
Mean Readings on Scale A (db)
Distance from Vehicle Banging Vehicle
Source (ft) Background Motor Cans Packer
2 58.8 96.9 95.5 92.0
10 63.6 87.7 85.6 83.8
50 58.3 76.8 81.1 74.5
100 53.5 70.0 75.0 66.0
-85-
-------
TABLE 23
CONSTANTS FOR USE IN THE NOISE RATING FORMULA
Mid-Frequency
of Octave Band a b
(cps) (db) (db)
500 4.8 0.974
1000 0 1.00
2000 -3.5 1.015
-86-
-------
TABLE 24
NOISE RATING NUMBERS - FIELD TESTS
Distance from
Source (ft)
2
10
50
Background
50
57
57
Vehicle
Packer/Motor0
88
77
70
Banging
Cans
86
82
72
The rating number entered is either the Packer or Motor number, whichever
was highest.
-87-
-------
TABLE 25
NOISE RATING NUMBERS0- LABORATORY TESTS
Distance from"
Source (Ft)
35
35
Dropc
Height (ft)
2
3
Metal Can
81
82
Polyethylene
Bag
53
58
Paper Bag
57
59
The numbers presented in the table are for asphalt which produced the
greatest noise.
D A distance of 35 ft was chosen because it was equivalent to the average
distance from the cans at the curb to the nearest room in residences on the
demonstration routes.
c For containers.
-88-
-------
TABLE 26
FREQUENCY DISTRIBUTION OF NUMBER OF LARVAE
MIGRATING FROM SOUD WASTE CONTAINERS
Containers Without Containers With
... ,, Polyethelene Liners Polyethelene Liners
Number of Larvae ' '
Collected During
8-Week Study (No.) (%) (No.) (%)
0
1-100
101-1,000
1,001-10,000
10,000
14
14
22
8
1
24
24
37
13
2
18
14
11
9
0
35
27
21
17
0
Total 59 100 52 100
Source: Reference 10.
-89-
-------
TABLE 27
FREQUENCY DISTRIBUTION OF NUMBER OF WEEKS MORE THAN
TWENTY LARVAE MIGRATED FROM SOLID WASTE CONTAINERS
Number of Weeks With
More Than 20 Larvae
Migrating from Solid
Waste Containers
0
1
-2
3
4
5
6
7
8
Total
Contair
PolyetK
(Ne.)
18
18
14
1
3
4
0
0
1
59
ters Without
elene Liners
(%)
30
30
24
2
5
7
0
0
2
100
Polyethelene
(No.)
23
12
8
4
2
0
2
1
0
52
With
Liners
(%)
39
28
16
7
4
0
4
2
0
100
Source: Reference 10.
-90-
-------
TABLE 28
STREET LITTER INDICES
Observation
Number
1
2
3
4
Area
Al
B3
B4
B3
B4
C5
C6
B3
B4
C5
C6
B3
B4
C5
C6
Street
Fairview
64th
Thoreau
111th
Ardath
Chanera
Thoreau
llth
Ardath
Chanera
Hill
Short
Plymouth (1)
Plymouth (2)
Thoreau
11th
Ardath
Chanera
Hill
Short
Plymouth (1)
Plymouth (2)
Thoreau
llth
Ardath
Chanera
Hill
Short
Plymouth (1)
Eucalyptus
Litter
Before
Collection
15.5
62.5
0
0
55.1
19.9
24.5
47.9
93.1
25.1
15.0
0
81.0
44.7
145.8
84.6
37.8
58.4
0
92.6
106.0
244.8
34.0
88.5
15.5
42.6
15.4
96.7
46.6
54.2
Index
After
Collection
0
0
0
0
0
0
0
0
0
0
0
0
0
43.4
0
0
0
0
0
0
0
167.8
0
0
0
0
0
0
0
0
Continued . . .
-91-
-------
TABLE 28 (Continued)
STREET LITTER INDICES
Litter Index0
Observation
Number
5
Area Street
Briarwood Chelsea (1)
Chelsea (2)
Kensington (1)
Kensington (2)
Mark ham
Feathers tone
Before
Collection
0
0
0
0
3.9
3.3
After
Collection
0
0
0
0
2.0
3.9
The litter index is defined as the sum of surface areas (one side only) of all
pieces of litter in the 1,000 sq ft test zone.
-92-
-------
TABLE 29
LITTER INDEX - BAGS VS. CANS
Bag
Before
Items, No.
3
5
3
5
4
5
4
10
0
9
6
3
2
0
2
4
Totals: 65
Avg.: 4.1
Route Col lection
Area, sq in.
15.5
62.5
19.9
55.1
15.5
42.6
15.4
96.7
0
92.6
93.1
25.1
15.0
0
37.8
58.4
645.2
40.3
After
Items, No.
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Items,
6
2
3
12
7
5
9
6
0
0
10
9
12
5
86
6.1
Can Route
Before
Collection
After
No. Area, sq in. Items, No.
34.0
88.5
24.5
47.9
81.0
44.7
145.8
84.6
0
0
106.0
244.8
46.6
54.2
1002.6
71.6
0
0
0
0
0
4
0
0
0
0
0
2
0
0
6
0.4
Area, sqin.
0
0
0
0
0
43.4
0
0
0
0
0
167.8
0
0
211.2
15.0
-93-
-------
TABLE 30
SUMMARY OF RESPONSES TO BIN LINER QUESTIONNAIRE0
Response
Item Yes No
Improvements
Fly problem 8 6
Odor control 10 4
Bin cleanliness 12 2
Reduction of frequency of need to clean bin 14 0
Difficulties
Installing liner into bin 6 8
Do you clean bin regularly? 8 6
Did you like the bin liners? 14 0
Should the City encourage bin liner use? 14 0
Total number of questionnaires returned was 14.
-94-
-------
TABLE 31
SUMMARY OF COMMENTS TO BIN LINER QUESTIONNAIRE0
Comment Number of Respondents
Positive
Improvement in operation 4
More sanitary 1
Saves maintenance 1
Total positive comments 6
Negative
Liners too small, therefore, hard to install 3
Need two people to fit liner 2
Collector should install liner 1_
Total negative comments 6
Total number of questionnaires returned was 14.
-95-
-------
TABLE 32
COMPARISON OF BIN COLLECTION TIME: WITH AND WITHOUT LINERS
Average time/task (min)
Task by Sequence With liner0 Without liner
Unhook liner from bin 0.21 0.0
Lifting bin on forkhook 0.10 0.10
Dump bin 0.11 0.10
Lowering bin 0.10 0.09
Total 0.52
, 15 samples
16 samples
-96-
-------
TABLE 33
POLYETHYLENE BIN LINER COST ANALYSIS0
Cost Items
extra i
Collection Cost Uner Cost Bin Cost Cleaning Cost
with liners $/t>in/yr
$/bin/service $/restaurant/yr $/l!ner $/resraurant/yr $/b!n $/bin/service $/restaurant/yr with liner without liner
0.0414 14.20 0.75 257.00 190.00 0.0369 12.66C 20 40
0.0554 19.00d
Incremental Cost Per Restaurant Per Year (Excludes normal collection costs): With liners-$303.86; Without liners-$59.00.
estimated from the Held survey for 3 cu yd bins and
Costs based on an average of 6.6 services/restaurant/week estimated from the field sui
2.0 mil liners.
" Estimated from current (1970) costs of $80 for cleaning one bin two (2) times per year.
c Assuming a 15-year bin life using liners.
^ Assuming a 10-year bin life without liners.
-------
TABLE 34
CAN COLLECTION DUST SAMPLES
Date:
Truck No.:
Weather:
Location:
Sampling Location:
Wind:
Containers:
January?, 1970
152
overcast
102nd Street and Prairie Avenue, Inglewood
5 ft above ground near hopper
slight breeze blowing across truck from south-southeast
cans
-98-
-------
TABLE 35
BAG COLLECTION DUST SAMPLES
Date:
Truck No.:
Weather:
Location:
Sampling Location:
Wind:
Containers:
January 27, 1970
128
cool and overcast
Eucalyptus Avenue and Fairview Boulevard (Study Route Al),
Inglewood
5 ft above ground near hopper
very slight breeze from the east
bags
-99-
-------
TABLE 36
PLATE COUNTS FOR MICROORGANISMS
FROM CAN COLLECTION DUST SAMPLES
Colony Counts0
Plate
No.
1°
2
3
4
5
6
7
8°
9
10
11
12
13
14
15
16°
17
18
19
20
21
22
23
24
25
26
27
28
29
30°
a
b
Bacteria
24
Hours
0
65
1000
320
350
30
375
90
100
75
100
40
10
5
20
70
30
15
60
25
100
65
500
550
200
15
120
75
20
0
Background samples.
48
Hours
1
300,
(2500)°
(800)b
500
90,
(940)b
160
170
150
140
60
30
15
70
70
80
55
120
60
230
140b
0250)°
0375)°
(500)b
40
250b
090)°
50
20
Fungi
24
Hours
0
85
800
100
110
45
125
0
35
50
20
10
0
3
15
0
50
10
10
90
90
50
80
60
160
10
30
60
10
0
48
Hours
0
370,
(2600)°
(325)b
200
nob
(400)b
0
80
170
35
35
0
5
100
0
130
40
50
200
160
130,
(260)°
095)°
(520)b
70
50 b
095)b
40
2
. 1 _*. •. 1
plates were uncountable at 48 hrs due to quantity of growth. Diameter of test plate,
100 mm.
c Microbic media plate counts were made following 68°F incubation.
-100-
-------
TABLE 37
PLATE COUNTS FOR MICROORGANISMS
FROM BAG COLLECTION DUST SAMPLES
Colony Counts
Bacteria
Plate 24
No.
la
2
3
4
5
6
7
8
9
10°
11
12
13
14
15
16
17
18
19
20°
21
22
23
24
25
26
27
28
29
30°
a
b
Hours
0
0
1
0
0
10
1
0
0
0
0
1
0
0
0
5
0
1
1
0
3
2
0
7
0
1
0
0
2
0
Background .
1 rtO MA^A |j? •••! 11 fc 11 • &«»A
48
Hours
0
3
4
3
20
15
40
3
2
0
0
4
2
5
1
15
1
6
2
0
20
10
1
15
0
20
5
8
5
0
* _ !._!<* • - - 1*1 _
Fungi
24
Hours
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
A XO C __•__ i.- _l_
48
Hours
0
7
10
0
60
30
25
4
3
1
1
30
12
35
5
80
10
5
10
0
30
5
2
70
0
100
12
15
2
0
-101-
-------
TABLE 38
NUMBER OF COLONIES PER PLATE0
Average Count
Bacteria Fungi
Background
24 hr 48 hr
Cans 40 63
Bags 0 0
Collection
Vehicle Sample
24 hr 48 hr
164 389b
1.4 8.1
Collection
Background Vehicle Sample
24 hr 48 hr 24 hr 48 hr
0 0.25 81 249^
0 0 0.15 21.7
L 100 mm diameter plate.
Values based on extrapolations.
-102-
-------
TABLE 39
LIST OF GROUP AND GENERA OF A FEW BACTERIA
ISOLATED FROM TEST CAN COLLECTION PLATES
Test
Plate'
5
8°
7
9
9
10
10
11
12
13
14
15
15
15
15
16°
17
18
18
18
18
21
23
25
26
26
26
27
30a
1
Gram
Reaction Morphology
+ Spherical
+ Spherical
+ Budding Cells
+ Spherical
Rods
Rods
Thin long rods
Rods
Rods
+ Spherical
+ Rods
Rods
+ Rods
+ Spherical
+ Spherical
+ Rods
Short rods
Short rods
+ Spherical
+ Budding cells
+ Spherical
+ Spherical
+ Spherical
Short Rods
Rods
Rods
+ Spherical
+ Spherical
+ Rods
+ Rods
Arrangement
of Cells Memo lysis
Chains +
Clusters
Group of 2 to 3
Pairs of two cells +
Individual and
chains of 3-5
cells
Short Chains
Pairs of 2-3
Single, Paired
Single, Paired
Clusters +
Chained, spore
forming
Single, Pairs
Chains, spore
forming
Pairs of two +
Clusters +
Chains, spores
Chains of 4-6 eel Is
Single, Pairs
Chains
Individual
Clusters
Chains +
Pairs of 2 +
Individual +
Short Chains
Short Chains
Chains +
Chains +
Chains, spores
Chains, spores
Genus
Streptococcus
Stophylococcus
Yeast
Diplococcus
Gram negative rod
Gram negative rod
Gram negative rod
Gram negative rod
Gram negative rod
Stophylococcus
Bacillus
Gram negative rod
Bacillus
Diplococcus
Staphvlococcus
Bacillus
Gram negative rod
Gram negative rod
Streptococcus
Yeast
Staphylococcus
Streptococcus
Diplococcus
Hemophi lus
Gram negative rod
Gram negative rod
Streptococcus
Streptococcus
Bacillus
Bacillus
Background samples.
-103-
-------
TABLE 40
FILAMENTOUS FUNGI ISOLATED FROM CAN COLLECTION TEST PLATES
Plate Number Genus of Fungi
2 Penici Ilium
5
Penici I Hum
£haetomium
7 Gymenoascus
Penici Ilium"
Choetomium
10 Mycelia sterilia
Penici Ilium
Mucor
13 Trichotheceiem.
Rhiquopus"
AspergilTus
Penici I Hum
15 Penici I Hum
Aspergillus
18 Rhizopus
Penici I Hum
19 Cylindrocarpon
Chaetomium
Penicillium
Aspergillus
22 Microspprum
Aspergillus~
Penicillium
27 Rhizopus
Mucor
Penicillium
-104-
-------
TABLE 41
MAJOR DISEASES CAUSED BY YEAST-LJKE MICROORGANISMS0
Disease
Organism
Remarks
Cryptococcosis
Blastom/cosis
Candidiasis
Cryptococcus
Neofbrmaus
Blostomysis
dermotitidis
Candica
albicans
Generally ulcers on skin,
spreading to blood stream or
nervous system.
Infects skin and lungs.
Infects skin, nails, mucous
membranes, lungs.
No project tests showed these organisms.
-105-
-------
TABLE 42
QUESTIONNAIRE 2: RESPONSES BY BAG SYSTEM
Private Apartment
Bag System Residents Dwellers Total
St. Regis Paper Bag with Holder 142 12 154
Mobil Keepaway and Friedman Narrow
Polyethylene Bags with Holders 109 5 114
International Paper Bag with
Holder 114 0 114
Friedman Wide Polyethylene Can Liner 89 32 121
St. Regis Paper Bag without Holder 32 1 33
-106-
-------
TABLE 43
QUESTIONNAIRE 3: RESPONSES BY BAG SYSTEM
Number of Responses
Bag System
Private
Residents
Apartment
Dwellers
Total
St. Regis Paper Bag with Holder
Mobil Keepaway Polyethylene Bag
with Holder
International Paper Bag with Holder
Wagner Polyethylene Can Liner
100
95
81
94
3
5
30
102
98
86
124
-107-
-------
TABLE 44
SUMMARY OF RESPONSES TO QUESTIONNAIRE 1 (PRE-TEST QUESTIONNAIRE)
o
00
Question
Total
Responses
(No.) Never Occasionally Sometimes Frequently Always Never Always
Responses (No,)
Responses (%)
Did you ever see spilled refuse in
the streets on your collection
day?
830
386
294
84
47
19
46
2
Did you ever see f 1 ies or ants in
your trash
cans?
853
439
255
110
41
8
51
1
Did you ever Find it difficult or
inconvenient to carry emptied
trash cans from the curb to your
storage area?
Does the collector ever leave small
amounts of refuse in trash cans?
How often are your trash cans
damaged by the collector?
Do you ever smell unpleasant
odors in your trash cans?
How often do you feel the appearance
of your neighborhood is less attrac-
tive when trash cans are at the curb
on collection day?
834
859
842
834
815
596
329
315
370
270
108
332
280
275
137
55
119
105
121
93
25
60
98
52
57
50
19
44
16
258
71
38
37
44
33
6
2
5
2
32
-------
TABLE 45
COMBINED SUMMARY OF RESPONSES TO QUESTIONNAIRES 2 AND 3
1 -
i mprov emcnrs
Holder and bag more attractive than
conventional solid waste containers
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bag or liner
Placing solid waste in bag
Closing bag
Carrying bags to curb
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
Mobil0 &
Holder
(212)d
Yes No
158 46
162 33
143 48
120 64
108 74
124 61
76 131
97 111
71 134
10 187
142 70
32 172
55
110
32
122
13
45
46
9
137 53
St. Rogisb
& Holder
(256)3
Yes No
211 36
213 29
187 44
168 58
167 60
166 60
42 210
28 223
65 178
23 121
181 60
19 228
127
101
14
52
42
11
59
1
210 32
International!
& Holder
(200)3
Yes No
151 33
154 30
130 43
115 62
115 64
111 59
22 170
33 150
60 128
26 162
174 16
17 176
95
73
14
48
48
15
46
2
151 31
3
Can Liner6
(245)*
Yes No
N.A.e N,A.
206 25
168 53
155 62
145 72
173 46
8 108
22 180
57 169
43 190
N.A. N.A.
N.A. N.A.
119
112
9
111
8
27
30
11
212 20
St. Regisb
No Holder
(36)*
Yes No
N.A. N.A.
29 3
23 5
17 9
18 10
16 12
5 16
8 21
13 21
5 29
N.A. N.A.
N.A. N.A.
16
18
3
9
8
6
7
2
28 5
Total .
(949)d
Yes No
520 115
764 119
651 193
585 255
553 280
590 238
153 635
188 705
266 630
107 789
497 146
68 576
412
414
72
344
119
104
188
25
738 141
Continued .
-------
TABLE 45 (Continued)
COMBINED SUMMARY OF RESPONSES TO QUESTIONNAIRES 2 AND 3
, Mobil Keepaway (2.5 mil) polyethylene bog.
Paper bag.
Combined responses for the Friedman Wide (3.0 mil) polyethylene can liner
(Questionnaire 2) and the Wagner (3.5 mil) polyethylene can liner (Questionnaire 3).
d Figures in brackets give number of questionnaires returned.
Not applicable.
-no-
-------
TABLE 46
COMBINED SUMMARY OF RESPONSES TO QUESTIONNAIRES 2 AND 3 (Expressed in Percentages)
Mobil0 & Holder
Yes No N.R.d
• _
impiuveiiteiiTS
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bag or liner
Placing solid waste in bag
Closing bag
Carrying bags to curb
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
74.5
76.4
67.5
56.6
50.9
58.5
35.8
45.8
33.5
4.7
67.0
15.1
64.6
21.7
15.6
22.6
30.2
34.9
28.8
61.8
52.4
63.2
88.2
33.0
81.1
25.9
51.9
15.1
51.9
5.5
19.1
19.6
3.9
25.0
3.8
8.0
9.9
13.2
14.2
12.7
2.4
1.9
3.3
7.1
0
3.8
10.4
St. Regis0 & Holder
Yes No N.R.
82.4
83.2
73.0
65.6
65.2
64.8
16.4
10.9
25.4
9.0
70.7
7.4
82.0
14.1
11.3
17.2
22.7
23.4
23.4
82.0
87.1
69.5
47.3
23.4
89.1
49.6
39.5
5.5
31.5
25.5
6.7
35.8
0.5
12.5
3.5
5.5
9.8
11.7
11.4
11.8
1.6
2.0
5.1
43.7
5.9
3.5
5.5
International0 &
Yes No
75.5
77.0
65.0
57.5
57.5
55.5
11.0
16.5
30.0
13.0
87.0
8.5
75.5
16.5
15.0
21.5
31.0
32.0
29.5
85.0
75.0
64.0
81.0
8.0
88.0
47.5
36.5
7.0
30.2
30.2
9.4
28.9
1.3
15.5
Holder
N.R.
8.0
8.0
13.5
11.5
10.5
15.0
4.0
8.5
6.0
6.0
5.0
3.5
9.0
Continued .
-------
TABLE 46 (Continued)
COMBINED SUMMARY OF RESPONSES TO QUESTIONNAIRES 2 AND 3 (Expressed in Percentages)
Can Linerc
Yes No N.R.
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bag or liner
Placing solid waste in bag
Closing bag
Carrying bags to curt)
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure'
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
N.A.e
84.1
68.6
63.3
59.2
70.6
3.3
9.0
23.3
17.6
N.A.
N.A.
86.5
N.A.
10.2
21.1
25.3
29.4
18.8
44.1
73.5
69.0
77.6
N.A.
N.A.
48.6
45.7
3.7
59.4
4.3
14.4
16.0
5.9
8.2
N.A.
5.7
9.8
11.4
11.4
10.6
52.7
17.6
7.7
4.8
N.A.
N.A.
5.3
St. Regis,b No Holder
Yes No N.R.
N.A.
80.6
63.9
47.2
50.0
44.4
13.9
22.2
36.1
13.9
N.A.
N.A.
77.8
N.A.
8.3
13.9
25.0
25.0
33.3
44.4
58.3
58.3
80.6
N.A.
N.A.
44.4
50.0
8.3
28.1
25.0
18.8
21.9
6.2
13.9
N.A.
11.1
22.2
27.8
25.0
22.3
71.7
19.5
5.6
5.5
N.A.
N.A.
8.3
Yes
77.8
80.5
68.6
61.6
58.3
62.2
16.1
19.8
28.0
11.3
74.4
10.2
77.8
Total
No
17.2
12.5
20.3
26.9
29.5
25.1
66.9
74.3
66.4
83.1
21.9
86.2
43.4
43.6
7.6
44.1
15.3
13.3
24.1
3.2
14.9
N.R.
5.0
17.5
11.1
11.5
12.2
12.7
17.0
5.9
5.6
5.6
3.7
3.6
7.3
-------
TABLE 46 (Continued)
COMBINED SUMMARY OF RESPONSES TO QUESTIONNAIRES 2 AND 3
(Expressed in Percentages)
, Mobil Keepaway (2.5 mil) polyethylene bag.
Paper bag.
Combined responses for the Friedman Wide (3.0 mil) polyethylene can liner
(Questionnaire 2) and the Wagner (3.5 mil) polyethylene can liner (Questionnaire 3).
" No
-
response.
Not applicable.
Percentages are based on total number of failure types reported.
-113-
-------
TABLE 47
SUMMARY OF COMMENTS FROM QUESTIONNAIRES 2 AND 3
Comments
Positive
Cleaner
Easy to use
Unlimited supply of
containers
Better area appearance
No can carrying to curb
and back
Less noise
Less odor
Less flies
Easy to carry
Able to locate near door
Saves cans
Capacity
Keeps cans clean
Very positive comments
Total Positive Comments
Negative
Had bag closure problem
Opening too small
Problem with yard solid
waste
Problem with lid
Problem changing bags
Problem with animal
damage
System awkward
Problem placing solid waste
in bag
Had ant problem
Mobil0
& Holder
14
7
2
10
13
2
0
1
1
0
N.A.e
0
N.A.
5
55
9
14
15
26
5
5
4
2
1
Ba
St. Regisb
16
14
5
7
15
4
2
0
0
0
N.A.
0
N.A.
18
81
9
3
7
2
4
9
4
0
4
g System
International
& Holder
15
8
1
12
19
3
1
0
0
1
N.A.
0
N.A.
14
74
9
11
14
0
1
7
1
2
7
Can Linerd
19
7
8
20
14
5
6
0
1
0
3
7
4
21
115
13
0
4
N.A.
1
9
1
0
1
Total
64
36
16
49
61
14
9
1
2
1
3
7
4
58
325
40
28
40
28
11
29
10
4
13
Continued
-114-
-------
TABLE 47 (Continued)
SUMMARY OF COMMENTS FROM QUESTIONNAIRES 2 AND 3
Bog System
Comments
Bag too small
Storage problem
Fly problem
Spillage problem
Container system hard to
move
Bags too flimsy
Odor problem
Maggots in bag
Bags will not stay on holder
Difficulty removing bag
from holder
Rats attacked bag
Lifting bag from can
Bag slides into can
Bag hard to carry
Causes extra work or time
Bag slippery
Concerned about rain on
paper bags
Green dye runs
Concerned about cost
Container tipped over
Very negative comments
Total Negative Comments
° Mobil Keepaway (2.
Paper bags with and
C n 1
Mobil0
& Holder
10
0
0
0
0
5
3
2
21
0
2
N.A.
N.A.
0
1
0
N.A.
0
15
0
1
139
, International
St. Regisb
1
2
1
1
2
0
0
0
0
0
0
N.A.
N.A.
0
0
0
8
2
11
0
3
65
& Holder
4
1
2
0
0
0
0
0
0
1
0
N.A.
N.A.
0
0
0
8
N.A.
7
1
2
71
Can Linerd
0
2
3
0
0
2
0
0
N.A*
N.A.
0
10
3
2
5
1
N.A.
0
17
0
4
77
Total
15
5
6
1
2
7
3
2
21
1
2
10
3
2
6
1
16
2
50
1
10
368
5 mil) polyethylene bag.
without holders.
Q
Combined responses for the Friedman Wide (3.0 mil) polyethylene can liner
(Questionnaire 2) and the Wagner (3.5 mil) polyethylene can liner (Questionnaire 3).
Not applicable.
-115-
-------
TABLE 48
SYSTEM COMPARISONS °
Attribute
Ease of Mounting Bag on
Holder
Ease of Placing Solid Waste
in the Bag
System Attractiveness re:
Cans/Bags
Holder Stability
Satisfaction with Holder
Lid Operation
In frequency of Failure
Reduction in Noise
Reduction in Odor
Reduction in Flies
Reducing Spillage
Improvement in Neighbor-
hood Appearance
Ease in Closing Bag
East of Carrying Filled
Bag
Acceptabi lity of System
Average
Mob!lb
& Holder
6.9/5.5
6.1/4.5
7.9/7.7
9.4/7.2
4.9/3.9
2.9/2.6
7.5/7.5
6.7/6.3
5.9/5.9
6.7/6.8
8.7/7.9
7.2/5.8
9.6/9.5
7.4/7.0
7.0/6.3
Bag System
St. Regisc Internationa lc
& Holder & Holder Can Linerd
8.6/7-8
8.9/9.0
8.6/8.5
9.5/8.9
9.7/8.9
5.6/4.8
7.6/8.9
7.4/7.5
7.4/7.4
7.1/7.8
8.7/9.1
7.3/7.4
9.0/9.2
8.4/9.1
8.1/8.2
9.5/8.3
8.5/8.0
8.3/8.4
9.3/9.1
9.4/8.9
5.1/5.0
7.8/7.3
6.3/6.8
6.7/6.1
6.1/7.2
8.8/8.1
7.5/6.2
8.8/8.5
8.4/8.6
7.9/7.6
N.A.e
9.3/8.4
N.A.
N.A.
N.A.
5.2/4.7
7.3/7.7
7.6/6.8
7.0/6.5
8.5/7.5
9.2/8.7
7.6/7.4
8.2/8.2
9.4/8.9
7.9/7.5
a , . , .. ..
The maximum and best number possible would be 10. The minimum and worst number
would be 0. The first number was derived from residents comparing the system to their
conventional containers* The second number was derived when residents compared
the system to other systems.
b Mobil Keepaway (2.5 mil) polyethylene bag.
0 Paper bag.
^ Combined results far Friedman Wide (3.0 mil) polyethylene can liner
(Questionnaire 2) and Wagner (3.5 mil) polyethylene can liner (Questionnaire 3).
Not applicable.
-116-
-------
TABLE 49
SUMMARY OF RESPONSES TO QUESTIONNAIRE 4 (BRIARWOOD CONDOMINIUM QUESTIONNAIRE)
Mobil0 & Holder
(Hl)b
Yes No
St. Regisc & Holder
(no)
Yes No
International6
& Holder (109)
Yes No
Mobil Flamegard (2.5 mi I)
bag.
Figures in parentheses give number of questionnaires returned.
c Paper bag.
Total
(330)
Yes No
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Tipping over of holder
Mounting bag
Placing solid waste in bag
Closing bag
Storing bag before use
Did holder lid function satisfactorily
Did bags fail often
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
81
78
78
64
47
61
2
3
5
12
2
84
3
26
0
3
0
4
88
17
17
15
22
27
22
98
96
93
84
94
8
91
8
82
81
80
64
50
62
4
23
7
14
30
97
7
7
3
2
3
2
91
26
21
20
33
36
35
98
87
103
94
76
6
100
12
78
67
53
48
37
44
3
18
15
25
40
95
4
6
4
3
0
0
83
30
28
38
39
48
44
106
91
91
80
65
12
102
21
241
226
211.
176
134
167
9
44
27
49
72
276
14
262
73
66
73
94
111
101
302
274
289
258
235
26
293
39
7
8
3
6
41
-------
TABLE 50
SUMMARY OF RESPONSES TO QUESTIONNAIRE 4 (BRIARWOOD CONDOMINIUM QUESTIONNAIRE)
(Expressed in Percentages)
Mobil0 & Holder St. Regisb & Holder
Yes No N.R.C Yes No N.R.
International
& Holder
Yes No N.R.
Total
Yes No N.R.
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Tipping over of holder
Mounting bag
Placing solid waste in bag
Closing bag
Storing bag before use
Did holder lid function satisfactorily
Did bags fail often
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
73.0
70.3
70.3
57.7
42.3
55.0
1.8
2.7
4.5
10.8
1.8
75.7
2.7
79.3
15.3
15.3
13.5
19.8
24.3
19.8
88.3
86.5
83.8
75.7
84.7
7.2
82.0
78.8
0.0
9.1
0.0
12.1
7.2
11.7
14.4
6.2
22.5
33.4
25.2
9.9
10.8
11.7
13.5
13.5
17.1
15.3
13.5
74.5
73.6
72.7
58.0
45.5
56.4
3.6
20.9
6.4
12.7
27.2
88.2
6.4
82.7
23.6
19.1
18.2
30.0
32.7
31.8
89.1
79.1
93.6
85.5
69.2
5.5
90.9
41.2
17.6
11.8
17.6
11.8
10.9
1.9
7.3
9.1
12.0
21.8
11.8
7.3
0.0
0.0
1.8
3.6
6.3
2.7
6.4
71.6
61.5
48.6
44.0
33.9
40.4
2.8
16.5
13.8
22.9
36.7
87.2
3.7
76.1
27.5
25.7
34.9
35.8
44.0
40.4
97.2
83.5
83.5
73.4
59.6
11.0
93.6
46.2
30.8
23.1
0.0
0.0
19.3
0.9
12.8
16.5
20.2
22.1
19.2
0.0
0.0
2.8
4.7
4.6
1.8
2.7
4.6
73.0
68.5
63.9
53.3
40.6
50.6
2.7
13.3
8.2
14.8
21.8
83.6
4.2
79.4
22.1
20.0
22.1
28.5
33.6
30.6
91.5
83.0
87.6
78.2
71.2
7.9
88.8
61.9
11.1
12.7
4.8
9.5
12.4
4.9
11.5
13.9
18.2
25.8
18.8
5.8
3.7
4.2
7.0
7.0
8.5
7.0
8.2
Continued . . .
-------
TABLE 50 (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 4
(BRIARWOOD CONDOMINIUM QUESTIONNAIRE)
(Expressed in Percentages)
, Mobil Flamegard (2.5 mil) polyethylene bag.
c Paper bag.
, No response.
Percentages are based on total number of faili
failure types reported.
-119-
-------
TABLE 51
SUMMARY OF COMMENTS FROM QUESTIONNAIRE 4
(BRIARWOOD CONDOMINIUM QUESTIONNAIRE)
&
Comments
Positive
No cans to carry out and back
Wish to continue system
Decomposes at the dump
No empty cans to publicize
absence
Efficient for City and homeowner
Easy to use
No cans to clean
More sanitary
Prefer polyethylene bags
How to obtain more
Compliment department
Save wear and tear on truck
Total Positive Comments
Negative
Too sma 1 l/weak/t hi n
Difficult to seal
Too expensive d
Like can better or as well
Harder to use
Too small an opening
Stand too high
Polyethylene containers are
better11
Too much bother
Total Negative Comments
Mobil0
Holder
(111)5
1
13
1
0
1
4
2
5
0
17
3
2
49
3
0
5
6
0
0
0
0
0
14
Bag
St. Regis0
& Holder
(no)
0
37
0
1
2
0
0
4
2
0
0
0
46
1
3
4
2
3
1
6
4
0
24
System
International
& Holder
(109)
2
27
0
2
2
0
0
5
4
0
0
0
42
4
0
1
1
0
4
0
6
3
19
Total
(330)
3
77
1
3
5
4
2
14
6
17
3
2
137
8
3
10
9
3
5
6
10
3
57
k Mobil Flamegard (2.5 mil) polyethylene bag.
Figures in parentheses give number of questionnaires returned.
, Paper bag.
Plastic containers are supplied free to people who live in Briarwood.
-120-
-------
N3
I
TABLE 52
QUESTIONNAIRE 5 (FOLLOW-UP QUESTIONNAIRE)
t
V
System Comparison
System used
Number preferring each system
System preferred
(expressed as percentage
of total usage)
Summary of Responses
Improvements;
Noise factor
Neighborhood appearance
Spillage
Difficulties:
Installing liner in barrel
Removing liner from barrel
Do you like the system
Mobil0
& Holder
68
28
41.2
Response
Yes
125
164
129
29
31
162
St. Regisb
& Holder
87
52
59.8
(202)"
No
48
19
42
116
112
15
International
& Holder
34
11
31.4
Yes
61.9
81.2
63.9
14.4
15.3
80.2
Can L?nerc
105
43
41.3
Response (Percent)
No
23.8
9.4
20.8
57.4
55.4
7.4
Chase Bagd
With Drawstring
108
31
28.7
N.R.f
14.3
9.4
15.3
28.2
29.3
12.4
Continued . . .
-------
TABLE 52 (Continued)
QUESTIONNAIRE 5 (FOLLOW-UP QUESTIONNAIRE)
Combined responses for Mobil Keepawoy and Flamegard (2.5 mil) polyethylene
bags. b
Paper bag.
° Combined responses for Mobil Luxri (1.5 mil), Friedman Wide (3.0 mil), and
Wagner (3.5 mil) polyethylene can liners.
° Polyethylene bag used on Mobil holder.
. Total number of questionnaires returned
No response.
-122-
-------
TABLE 53
SUMMARY OF COMMENTS FROM QUESTIONNAIRE 5
(FOLLOW-UP QUESTIONNAIRE)
Comments
Positive
Wish to continue system
Neater in home and community
Efficient for City and homeowner
Easy to use
Strong
More sanitary
Liked heavy polyethylene bags
No odor problem
No cans to carry out and back
L/vGOrnpOSOS Or QUmp
Holds a lot
No empty cans to publicize absence
Total Positive Comments
Negative
Top thin, weak, tearing
No good for yard trimmings
Difficult to use/hard to fill
No more taxes, too expensive
Animals and bugs get to bags
Punctures easily
Mobil0
& Holder
6
0
1
4
0
0
0
3
1
0
0
0
15
2
4
9
8
1
3
St. Regisb
& Holder
11
11
9
6
4
5
0
2
2
3
3
1
57
3
10
1
9
6
0
Bag
International
& Holder
1
3
3
1
0
0
0
0
1
0
0
0
9
0
0
0
0
1
1
System
Can Liner0
7
12
5
1
4
5
0
1
1
1
1
1
39
25
16
11
7
13
5
Chase Bagd
With Drawstring
3
1
0
1
5
0
3
0
1
1
1
16
8
4
10
7
8
5
Total
28
27
18
13
13
10
3
6
6
5
5
2
136
38
34
31
31
29
14
Continued
-------
TABLE 53 (Continued)
SUMMARY OF COMMENTS FROM QUESTIONNAIRE 5
(FOLLOW-UP QUESTIONNAIRE)
Comments
Negative
Unsatisfactory
Too small of opening
Prefer cans
Market them on ly for those who
want them
Holder ineffective
Make larger
Make lid stay open
Make bags of heavier polyethylene
Make liners with drawstrings
Odor problems
Paper not good for wet items
Unnecessary
Put wheels on holder
Total Negative Comments
Mobil0
& Holder
2
2
1
1
5
2
4
0
1
1
N.A.
1
1
48
St. Regisb
& Holder
3
3
1
3
0
0
0
N.A.
N.A.
0
2
0
0
41
Bog
International
& Holder
0
0
0
0
0
0
0
N.A.
N.A.
0
0
0
0
2
System
Can linerc
5
4
4
0
N.A.e
1
N.A.
0
1
2
N.A.
0
N.A.
94
Chase Bag**
With Drawstring
2
0
0
1
0
2
0
3
1
0
N.A.
0
0
51
Total
12
9
6
5
5
5
4
3
3
3
2
1
1
236
liner.
, Combined responses for Mobil Keepaway and Flamegard (2.5 mil) polyethylene bags.
c Paper bag.
Combined responses for Mobil Luxri (1.5 mil), Friedman Wide (3.0 mil), and Wagner (3.5 mil) polyethylene can
Polyethylene bag used on Mobil holder.
Not applicable.
-------
TABLE 54
DIMENSIONAL PROPERTIES OF BAG SAMPLES TESTED IN LABORATORY
Company
Identification Material
Mobil (Flamegard) Polyethylene
Mobil (Luxrl Liner)
Mobil (Keepaway)
Bemis "
Bemis "
Bemis "
Rapco "
Central Bag "
Friedman (Wide)
Friedman (Narrow)
Wagner "
Chase (Drawstring) "
Capacity (gal)
35
45
32
32
32
32
25
20
45
32
45
20
Wall Thickness (mil)
2.5
1.5
2.5
2.0
4.0
6.0
3.2
2.0
3.0
2.5
3.5
2.5
Company ,
Identification Material0 No. Plys Basis Wt (Ib) Capacity (gal)
Westvaco Paper
St. Regis (Hand! -sack)
Bemis "
International (Garbax) "
1
2
1
2
100
50
60
50
30
32
32
35
All bags wet-strength, Kraft paper.
Basis weight of 3,000 sq ft of single-ply paper or a ream of 500 sheers of
24" x 36" size (Ref. ASTM Standards, Part 15, April 1965).
-125-
-------
to
o
TABLE 55
AVERAGE FAILURE LOADS (LB)
Bag
Manufacturer
Paper
St. Regis? (1/50)
St. Regis (1/50)
International
(2/50)c
Polyethylene .
Bemis (2 mil)J
Bemis (4 mil)
Bemis (6 mil)
Rapco (3. 2 mil)
Central Bag
(2 mil)
Mobil6
(2.5 mil)
Friedman (W)
(3.0 mil)
Friedman (N)
(2.5 mil)
Wagner
(3. 5 mil)
Chase (2.5 mil)
Longi-
tude
34.30
41.00
68.52
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
Tensile
Trans-
verse
21.74
34.54
42.40
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
Unspeci-
fied Cut
N.A.
N.A.
N.A.
2.50
4.50
7.00
3.00
2.25
2.80
3.75
2.93
3.53
2.10
Longitudinal Specimens
Cottonseed Oil Vegetable Oil Milk Butter Water
24 Hr
24 Hr 48 Hr 72 Hr 24 Hr 48 Hr 72 Hr 24 Hr 24 Hr Wet Dry
32.00 33.40 33.80 37.20 32.70 38.40 6.60 30.86 7.26 36.60
33.34 39.20 35.00 32.06 35.40 40.60 8.26 33.60 8.06 34.00
-
57.88 49.20 66.00 61.30 65.20 62.80 15.70 55.60 16.28 58.00
2.50 2.50 2.25 2.25 2.25 2.25 3.00 3.75 2.50 2.50
3.75 3.75 4.50 3.75 4.50 3.75 4.50 4.75 3.50 4.25
5.75 5.75 6.50 5.75 7.00 7.00 7.25 7.25 5.75 7.00
3.50 3.25 3.50 3.25 3.25 3.00 3.50 3.25 3.00 3.00
2.25 2.25 2.25 2.25 1.50 N.A. 2.00 1.50 2.25 2.25
f
Continued . . .
-------
TABLE 55 (Continued)
AVERAGE FAILURE LOADS (LB)
Bag
Manufacturer
Paper
St. Regis? (1/50)
St. Regis0 (1/50)
International
(V50)C
Polyethylene
Bemis (2 mil)d
Bemis (4 mil)
Bemis (6 mil)
Rapco (3.2 mil)
Central Bag
(2 mil)
Mobil0
(2.5 mil)
Friedman (W)
(3.0 mil)
Friedman (N)
(2.5 mil)
Wagner
(3.5 mil)
Chase (2. 5 mil)
Temperature
Exposure
24 Hr
110 F 32 F
33.54
41.34
67.08
N.D.
N.D.
N.D.
N.D.
N.D.
3.10
3.70
3.10
3.01
N.D.
34.30
41.94
61.20
2.75
4.50
7.00
3.00
1.75
3.05
3.45
2.80
3.01
N.D.
Perforation
(Dia.)
3/32 in. 1/8 in.
27.66
27.46
31.60
2.25
4.00
6.75
2.75
1.75
1.20
1.65
1.43
1.85
N.D.
25.20
21.46
26.52
2.25
3.75
6.75
2.75
1.75
1.20
1.65
1.38
1.53
N.D.
1/4 in.
11.80
12.06
15.68
2.25
3.75
6.25
2.25
1.75
0.93
1.13
1.05
0.90
N.D.
Pin
Holes
(Dia.)
3/8 in.
34.66
36.90
62.12
2.50
4.00
6.75
2.75
1.75
1.87
2.32
2.17
1.80
N.D.
1/8 in.
10.00
11.20
14.20
1.25
1.50
3.25
1.50
1.00
1.32
1.90
1.50
1.82
1.70
Puncture
(Dia.)
1/4 in.
19.40
27.80
28.40
3.00
4.00
7.00
3.25
2.00
2.70
3.70
3.20
4.22
2.92
1/2 in.
31.60
46.80
48.60
6.00
6.75
12.50
7.50
4.25
6.27
8.80
6.90
9.47
7.22
Continued . . .
-------
TABLE 55 (Continued)
AVERAGE FAILURE LOADS (LB)
• Outside layer.
Inside layer,
C .,,_ 2 = Number of Plys
/:> 50 = Basis Weight of Ply (Ib) per 200 bags
J Imil =0.001 in.
Mobil Keepaway and Mobil Flamegard were both 2.5 mil thickness and had
identical physical properties.
' Because earlier oil, milk, butter, and water tests on the Bern is, Rapco, and
Central polyethylene bags indicated little discernible effect, these tests were not run
on the Mobil, Friedman, and Wagner polyethylene bag samples.
Note: N.A. = Not applicable.
N.D. = Not determined.
-128-
-------
TABLE 56
CREEP TESTS ON POLYETHYLENE BAGS AND UNERS
Recovery (Percent reduction in strain
otter removing the load)
Contrqlled Environment0 Field Environment
Sample
Mob!lb (2.5 mil)
Friedman (2.5 mi!)
Friedman (3.0 mil)
Wagner (3.5 mil)
• Specimens
D M«lttl Ktuk
Use
Bag
Bag
Liner
Liner
were tested
nnu«iv nnrl f
Longitudinal
17.3
52.5
36.0
50.0
Transverse
14.3
50.0
23.5
18.7
in a room maintained at 74
•InntAnnrrl 9 *? mtl knnc knrl
Longitudinal
14.3
48.0
33.5
25.0
26.2
19.1
Transverse
7.15
35.7
14.3
18.2
N.D.C
N.D.
12 F and constant humidity.
irlnnti^nl nrnnnrtiac
Not determined.
-129-
-------
TABLE 57
MOISTURE ABSORPTION0
Company
West Virginia
St. Regis
Bemts
Original
Moisture
Content
10.3
9.1
10.8
24 hr
97.0
101.9
88.2
Hours of Exposure
48 hr
107.5
124.8
143.1
72 hr
125.4
129.5
147.1
Percent of original weight (dry basis) of paper bag sample.
-130-
-------
TABLE 58
MOISTURE EVAPORATION0
Company
West Virginia (paper)
Bemis (paper)
Mobflb (polyethylene)
24 hr
0.0069
0.0435
0.0004
Hours After
48 hr
0.0515
0.0907
0.0009
Sealing Bag
72 hr
0.0852
0.1313
0.0013
96 hr
0.0867
0.1362
0.0014
. Grams of water lost per square inch of sample bag surface.
Mobil Keepaway and Flamegard 2.5 mil bag specimens.
-131-
-------
TABLE 59
DIMENSIONAL CHARACTERISTICS OF BAGS AND CAN LINERS TESTED IN FIELD
I
CO
I
Specification Wall Circumference Length
Company Material Use Thickness (mil) (in.) (in.)
St. Regis (Hand! -sack) Paper Bag
International (Garbax)
Mobil (Keepaway) Polyethylene
Mobil (F Iomega rd)
Friedman (Narrow)
Chase (Drawstring)
Mobil (Luxri Liner) " Liner
Friedman (Wide)
Wagner
9.0
9.5
2.5
2.5
2.5
2.5
1.5
3.0
3.5
56.0
54.5
53.5
53.5
54.5
47.5
52.0
70.0
71.0
28.8
42.0
35.5
43.0
36.0
36.0
43.0
44.1
44.0
Volume
(cu in.)
7,174
8,654
7,092
8,590
7,785
4,670
11,264
13,838
14,045
Basis Wt°
(Ib)
50
50
N.A.C
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
No. of
Plys
2
2
1
1
1
1
1
1
1
Basis weight of 3,000 sq ft of single-ply paper or a ream of 500 sheets of 24" x 36" size (Ref. ASTM Standards,
Part 15, April 1965).
b All bags wet-strength, extensible Kraft paper.
Not applicable.
-------
TABLE 60
SUMMARY OF MATERIAL AND BAG PROPERTIES
Bag
Use
Volume
(cuin.)
Unit
Cost0
C*x 10-*
(C/cu in.)
Specification
Thickness
(mil)
0*0
au
CO
CO
Paper
St. Regis
International
Dry"
Wete
w .e
Polyethylene
Mobil (Keepaway)
Friedman (Narrow)
Chase (Drawstring)
Mobil (Luxri Liner)
Friedman (Wide)
Wagner
Bag
Bag
Bag
Bag
Liner
Liner
Liner
7,174 9.603 1.3
8,654 9.215 1.1
7,092 6.95 0.98
7,785 7.049 0.91
4,670 8.736 1.87
11,264 5.5 0.49
13,838 13.68 0.99
13,838 13.00 0.94
9.5
9.0
2.5
2.5
2.5
1.5
3.0
3.5
7,150 0.03
1,374 0.04
5,750 0.085
1,473 N.D.
2,100 4.0
2,344 2.5
2,175 5.3
2,0009 4.59
2,500 6.0
2,100 4.5
0.22
f 0.26
.0
.0
.0
.0
.0
.0
262
144
234
N.D.
6,000
4,700
7,573
7,264s
7,300
6,250
2.48
1.46
2.11
N.D.
15.0
11.8
18.9
10.9°
21.9
21.9
a
b
c
d
e
f
g
Data is based on cost of bags purchased for present field study.
This is the manufacturer's specification thickness and not the measured thickness of the actual test specimen.
Based on tensile test data, reference Figure 39, 40, and 41.
Average volumes compiled from transverse and longitudinal tests conducted on inner and outer bag layers.
Wet samples (24 hour).
Not determined.
Average values from opposite sides of the bag. Differences of the order of 50 percent were recorded.
-------
TABLE 61
HOUSEHOLDERS' RATINGS (af)
FOR TOTAL EVALUATION OF BAG SUITABILITY
Question-
naire Mob IP
Factors Number & Holder
1.
2.
3.
4.
5.
6.
7.
Frequency of Bag
Failure
Ease of Closure of
Filled Bag
Ease of Mounting
Bag or Liner
Ease of Filling
Bag
Odor Control
Frequency of
Spillage
Frequency and
Extent of
Animal Damage
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
5.13
7.44
10.0
9.44
7.94
10.0
7.52
7.03
10.0
6.50
5.03
10.0
8.75
8.50
10.0
7.89
8.65
10.0
6.95
8.12
10.0
Ratings0 (a;)
Inter-
St. Regis0 national0 Can
& Holder & Holder Linerd
10.0
10.0
9.65
9.62
9.97
9.95
9.38
10.0
9.14
9.55
10.0
9.88
9.72
10.0
9.07
8.34
10.0
8.70
2.70
8.78
8.24
9.40
8.97
9.94
9.87
8.07
8.71
10.0
10.0
9.65
9.16
8.76
9.05
8.27
9.04
7.59
7.21
9.05
6.80
4.77
8.12
10.0
9.82
9.99
10.0
10.0
9.70
9.70
10.0
9.43
10.0
8.96
10.0
9.47
10.0
10.0
St. Regis0
No Holder
8.87
4.94
5.27
7.78
8.75
6.79
4.89
Continued . . .
-134-
-------
TABLE 61 (Continued)
HOUSEHOLDERS' RATINGS (a,)
FOR TOTAL EVALUATION OF BAG SUITABILITY
Ratings are derived from responses to Questionnaires 2, 3, and 4 which are
given in Tables H2, H4, and 50, respectively.
b Ratings for Questionnaires 2 and 3 refer to the Mobil Keepaway (2.5 mil)
polyethylene bag. Ratings for Questionnaire 4 refer to the Mobil Flamegard (2.5 mil)
polyethylene bag.
*j Paper bag.
Ratings for Questionnaire 2 refer to the Friedman Wide (3.0 mil) polyethylene
can liner. Ratings for Questionnaire 3 refer to the Wagner (3.5 mil) polyethylene can
liner.
-135-
-------
TABLE 62
QUESTIONNAIRES, IMPORTANCE RATINGS
(Number of Responses)
Item
None
Importance
Very Little Moderate
Great
Frequency of Bag Failure
Ease of Closure of Filled
Ease of Mounting Bag or
0
1
14
14
14
11
Liner
Ease of Filling Bag
Ease of Operations of
Holder Ltd0
Odor Conditions
Ease of Storage of Bag
Supplyb
Ease of Carrying Filled
Bagb
Frequency of Spillage
Frequency and Extent
of Animal Damage
2
1
2
2
7
4
0
2
7
3
3
0
8
6
8
4
9
12
13
9
8
14
11
9
10
15
12
19
9
6
14
14
Item was not used in subsequent algorithm ratings (o;bj) because it pertained
only to bags on holders.
b Item was not used in subsequent algorithm ratings (a*b>) due to insufficient
data from questionnaires 2 and 4.
-136-
-------
TABLE 63
QUESTIONNAIRE 5, IMPORTANCE RATINGS
(Expressed as Percentages of Total Response)
Item
Frequency of Bag Failure
Ease of Closure of Filled
Bag
Ease of Mounting Bag or
Liner
Ease of Filling Bag
Ease of Operations of
Holder Lida
Odor Conditions
Ease of Storage of Bag
Supplyb
Ease of Carrying Filled
Bagb
Frequency of Spillage
Frequency and Extent
of Animal Damage
None
0
3.1
7.1
3.2
6.7
6.7
21.9
13.3
0
6.9
Importance
Very Little Moderate
12.4
18.8
25.0
9.7
10.0
0
25.0
20.0
24.2
13.8
43.8
43.8
32.1
38.7
43.3
30.0
25.0
46.7
33.3
31.1
Great
43.8
34.3
35.8
48.4
40.0
63.3
28.1
20.0
42.5
48.2
Item was not used in subsequent algorithm ratings (ajbj) because it pertained
only to bags on holders.
° Item was not used in subsequent algorithm ratings (a^b;) due to insufficient
data from questionnaires 2 and 4.
-137-
-------
TABLE 64
WEIGHTING COEFFICIENTS (bj)
FOR TOTAL EVALUATION OF BAG SUITABILITY
a Veryb c d Total Weighting
Item None Little Moderate Great Units Coefficient (bj)
1.
2.
3.
4.
5.
6.
7.
Frequency of Bag
Failure 0
Ease of Closure of
Filled Bag 0
Ease of Mounting
Bag or Liner 0
Ease of Filling Bag 0
Odor Control 0
Frequency of
Spillage 0
Frequency and
Extent of
Animal Damage 0
r o
12.4 87.6 131.4 231.4
18.8 87.6 102.9 209.3
25.0 64.2 107.4 196.6
9.7 77.4 145.2 232.3
0 60.0 189.9 249.9
24.2 66.6 127.5 218.3
13.8 62.2 144.6 220.6
103.9 505.6 948.9 1,558.4
0.149
0.134
0.126
0.149
0.160
0.140
0.142
1.000
, Assign zero units.
Assign one unit.
, Assign two units.
Assign three units.
-138-
-------
TABLE 65
ALGORITHM RATINGS (a;bf)
FOR TOTAL EVALUATION OF BAG SUITABILITY
Question-
naire Mobil0
Factors Number & Holder
1.
2.
3.
4.
5.
6.
7.
Frequency of Bag
Failure
Ease of Closure of
Filled Bag
Ease of Mounting
Bag or Liner
Ease of Filling
Bag
Odor Control
Frequency of
Spillage
Frequency and
Extent of
Animal Damage
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
2
3
4
0.764
1.109
1.490
1.265
1.064
1.340
0.948
0.886
1.260
0.969
0.749
1.490
1.400
1.360
1.600
1.105
1.211
1.400
0.987
1.153
1.420
Weighted Ratings (ajbj)
, Inter- ,
St. Regis national Can
& Holder & Holder LinerC
.490
.490
.438
.289
.336
.333
1.182
1.260
1.152
.423
.490
.472
.555
.600
1.451
1.168
1.400
1.218
0.383
1.247
1.170
1.401
.337
.481
.323
.081
.167
1.260
1.260
1.216
1.365
1.305
1.348
1.323
1.446
1.214
1.009
1.267
0.952
0.677
1.153
1.420
1.463
1.489
1.340
1.340
1.222
1.222
1.490
1.405
1.600
1.434
1.434
1.400
1.326
1.420
1.420
St. Regisb
No Holder
1.322
0.662
0.664
1.159
1.400
0.951
0.694
Continued .
-139-
-------
TABLE 65 (Continued)
ALGORITHM RATINGS (a;b;)
FOR TOTAL EVALUATION OF BAGS SUITABILITY
Weighted Ratings (o;b;)
Factors
Total Bag Ratings
7
a;b;
i = 1
Average Rating
Question-
naire
Number
2
3
4
2,3,4
Mobil0
& Holder
7.438
7.532
10.000
(7.485?
10.000
St. Regis
& Holder
8.490
9.823
9.234
9.182
Inter-
national
& Holder
8.358
8.849
8.748
8.652
Can
Liner
9.935
9.636
9.786
St. Regisb
No. Holder
6.852
6.852
Ratings for Questionnaires 2 and 3 refer to Mobil Keepaway (2.5 mil)
polyethylene bag. Ratings for Questionnaire 4 refer to Mobil Flamegard (2.5 mil)
polyethylene bag.
Paper bag.
° Ratings for Questionnaire 2 refer to the Friedman Wide 0.0 mil) polyethylene
can liner. Ratings for Questionnaire 3 refer to the Wagner (3.5 mil) polyethylene can
liner.
Average for Mobil and Holder on all three questionnaires is not valid due to the
change in holder model and its effect on the system rating as reflected in responses to
Questionnaire 4 when compared to Questionnaires 2 and 3.
-140-
-------
TABLE 66
COLLECTION TIMES
rx . _.. x- c- Time, t, in Minutes per Stop
Designated Crew Size f~ K
(CS) Cans
a
Oneb
Twoc
Three6
0.74
0.69
0.58
0.58
0.53
0.41
Minutes per stop includes travel time to the next stop. Data was taken during
the demonstration study for one-man crews. Simulations of two- and three-man crews
were based on MTM analyses.
° Actual times recorded during collection in Inglewood.
c Derived by Methods-TIme-Measurement (MTM) analysis. Times for standard
work-task elements of a collector during waste collection were determined for each
task from field data and used to construct the work-task collection times for 2 and 3
men. Travel time Is constant for all crew sizes.
-141-
-------
-U
ro
TABLE 67
COSTS OF VEHICLE TIME - EQUIPMENT COST ONLY0
Truck Sizeb
Collection Time
Haul Time
Relief Time
12cuyd
$3.75/hr
6.25$/min
$4.00/hr
6.67$/min
$2.00Ar
3 .33$/min
1 6 cu yd
$3.90Ar
6.50c/min
$4.35/hr
7.25^/min
$2.18/hr
3.63<:/min
20 cu yd
$4.12/Kr
6.85^/min
$4.60Ar
7.67^/min
$2.30/hr
3.83t/min
25 cu yd
$4.20Ar
7.00C/min
$5.10Ar
8.50^/min
$2.55Ar
4.25c/min
32 cu yd
$4.73/hr
7.90^/min
$5.74/hr
9.57$/min
$2.87Ar
4.7&f/min
40cuyd
$5.10/hr
8.50t/min
$6.20/hr
10.33«f/min
$3JOAr
5.17
-------
TABLE 68
UNIT COSTS OF CAN AND BAG SYSTEMS'
CO
Container
System
Cans:
Metal
Plastic, L.D.e
Plastic, H.D.
Liner:
Polyethylene
(Mobil Luxri)
Bags:
Paper
(St. Regis)
Polyethylene
(Mobil Keepaway)
Bin Liner:
Polethylene
(Bemis 3 cu yd)
Wholesale Price Schedule6
$/
$/ container $/nolder
container
N.A/
N.A.
N.A.
0.055
0.09603
0.0695
0.4294
service
N.A.
N.A.
N.A.
0.055
0.09603
0.0695
0.4294
I/holder
N.A.
N.A.
N.A.
6.23
12.00
8.90
t
190.001
service
N.A.
N.A.
N.A.
u
0.024h
s
0.0231
0.0171
0.0369
Retail Price
$/
$/ container
container
4
5
9
0
0
0
0
.79
.99
.49
.0799
.09603
.117
.85
service
0.12°
0.15
0.237
0.0799
0.09603
0.117
0.85
Schedule0
I/holder
$/holder
N.A.
N.A.
N.A.
6.23
12.00
5.79
190.00
service
N.A.
N.A.
N.A.
0.024
0.0231
0.0112
0.0369
Collection Costd
S/container/servIce
25 cu yd 35 cu yd
truck
0.098
0.098
0.098
0.0629
0.0629
0,0629
0.0629
truck
0.0915
0.0915
0.0915
0.0684
0.0684
0.0684
0.0684
Continued . . .
-------
TABLE 68 (Continued)
UNIT COSTS OF CAN AND BAG SYSTEMS0
All costs are based on 32 gal container capacities. Tax is not included.
Service weekly, 52 times per year.
Wholesale prices are lot sizes greater than 1,000, based on demonstration
project costs, 1969-1970 (Table II).
Retail prices are based on August 1970 store prices.
Collection costs are from Figure 53, based on field survey motion-time
studies; 411 bag services per day, 325 can services per day.
6 L.D. = light duty; H.D. = heavy duty.
Not applicable.
Costs based on 2 year can life; 2.6 cans/unit/service; as follows:
2.6 x S/container */ . . /
-= =5 : 7— = $/container/service.
2 yr x 52 services/yr
Based on 5 year can life using one can as a holder.
•
Based on 10 year holder life.
' Bin prices based on Dempster 3 cu yd bin, 10 year life without liner, 15 year
life with liner, 6.6 services per week.
-144-
-------
TABLE 69
COST ANALYSIS - CAN AND BAG SYSTEMS - CITY (WHOLESALE) DISTRIBUTION SYSTEM
($/residence/year)
Container
System
Cans:
Metal
Plastic, L.D.
Plastic, H.D.
Liner:
Polyethylene
in can6
on holder ^
Bags:
Paper h
Polyethylene '
25 CU YD TRUCKS
Container
Container Holder Distribution0 Collection
c
N.A.
N.A.
N.A.
7.43
8.86
15.48*
11.20
N.A.
N.A.
N.A.
1.25f
0.89
1.20
0.89
N.A.
N.A.
N.A.
4.34
4.34
4.34
4.34
13.26
13.26
13.26
8.50
10.14
10.14
10.14
35 CU YD TRUCKS
Container, holder
and Distribution ,
b Total Costs Collection0 Total
13.26
13.26
13.26
21.52
24.23
31.16
26.57
N.A.
N.A.
N.A.
13.02
14.09
21 .02 '
16.43
12.38
12.38
12.38
9.25
11.02
11.02
11.02
12.38
12.38
12.38
22.27
25.11
32.04
27.45
Continued . . .
-------
TABLE 69 (Continued)
COST ANALYSIS - CAN AND BAG SYSTEMS - CITY (WHOLESALE) DISTRIBUTION
SYSTEM
° Container distribution costs are the direct labor and equipment costs
incurred in distributing the bags to residences during the study.
" Collection costs taken from Figure 53.
c Not applicable.
d Mobil Luxri 1.5 mil liner.
e Liners in can costs are based on 2.6 liners per week equivalent to 2.6
cans per week. Assumes liners in cans are Filled as much as cans alone.
Holder is one can depreciated over 5 years.
9 Liners on holders. Liners sold in retail stores are for use in cans or
hung from holders based on 3.1 liners per week. Assumes liners are filled as much
as bags. h
• St. Regis bag; costs are based on 3.1 bags per week.
Paper bags are not presently distributed through retail stores but are
available to individuals at the quoted wholesale price from the manufacturer.
I Mobil Keepaway 2.5 mil bag; costs are based on 3.1 bags per week.
-146-
-------
TABLE 70
COST ANALYSIS - CAN AND BAG SYSTEMS - PRIVATE (RETAIL) PURCHASE SYSTEM
($/residence/year)
Container
System
Cans:
Metal
Plastic, L.D.b
Plastic, H.D.
Liner:
Polyethylene6
in can
on holder6
Bags:
Paperf
Polyethylene
Container
6.23
7.80
12.32
10.79
12.86
15.489
18.86
25 CU YD TRUCKS
Haider Collection0
0 13.26
0 13.26
0 13.26
1.25 8.50
0.59 10.14
1.20 10.14
0.59 10.14
Total
19.49
21.06
25.58
20.54
23.59
26.82
29.59
Container
and hblder
Costs
6.23
7.80
12.32
12.04
13.45
16. 6S8
19.45
35 CU YD TRUCKS
Collection0
12.38
12.38
12.38
9.25
11.02
11.02
11.02
Total
18.61
20.18
24.70
21.29
24.47
27.70
30.47
Continued . . .
-------
TABLE 70 (Continued)
COST ANALYSIS - CAN AND BAG SYSTEMS - PRIVATE (RETAIL) PURCHASE SYSTEM
($/residence/year)
Q
i Collection costs taken from Figure 53.
L.D. = light duty; H.D. = heavy duty.
C Mobil Luxri 1.5 mil liner.
Liners in can costs are based on 2.6 liners per week equivalent to 2.6
cans per week. Assumes liners in cans are Filled as much as cans alone.
e Liners on holders. Liners sold in retail stores are for use in cans or hung
from holders based on 3.1 liners per week. Assumes liners are filled as much as bags.
St. Regis bag; costs are based on 3.1 bags per week.
* Paper bags are not presently distributed through retail stores but are
available to individuals at the quoted wholesale price from the manufacturer.
-148-
-------
TABLE 71
BENEFIT-COST EVALUATION FOR HOUSEHOLDERS0
($/residence//ear)
Wholesale
Container System Costs
Cans:
Metal .
Plastic, L.D.^
Plastic, H.D.
Liner, Polyethylene:
in can
on holder
Bags:
Paper
Polyethylene
N.A.C
N.A.
N.A.
22.15
24.98
31.90
27.32
Retail
Costs
18.74
20.29
24.79
21.18
24.33
27.55
30.38
Benefit b
Incentive
0
0
0
6.76
6.76
6.76
6.76
Net Cost Less Benefit
Wholesale Retail
N.A.
N.A.
N.A.
15.39
18.22
25.14
20.56
18.74
20.29
24.79
14.42
17.57
20.79
23.62
a Data is the weighted average for 18-35 cu yd trucks and 3-25 cu yd trucks
from Tables 69 and 70.
b Benefits are determined from savings in washing calculated as follows:
Labor = 3 min per can at $1.50 per hr or $.025 per min = $.075; detergent and
water = $.055; total cost per can = $0.13/washing; 2 cans washed every 2 weeks.
c Not applicable.
d L.D. - light duty; H.D. - heavy duty.
-149-
-------
TABLE 72
EFFECTS OF BAGS ON COLLECTION VEHICLE WASTE DENSITIES
Route
Trips per Route
Week No.
12345
Solid Waste Vehicle Load
(tons per 25 cu yd vehic le)
1 (bag) 1 1
10.5 10.6 10.7 10.7°
2 (can) 1 1
8.8 9.7 9.5 9.7
3 (can)
1 1+ 1+ 1 +
10.9 9.3C ll.QC 10.7C
4 (bag)
111+1
10.2 10.2 11.3C 10.5
5 (bag) 1 1+ - 1+ -
10.4 9.7° 9.9C
6 (can) 1 + 1 + - 1
9.2C 8.5C 8.5C
Packer
Bag Routes 1
856
Can Routes 2
(no fully loaded
vehicles were
observed)
Density
4
907
3
741
878
856
(Ib/cu yd)c
5
772
788
6
737
680
681
Mean
Density
831
762
a No observation.
b Vehicle returned to the route From the landfill and collected a partial load.
c Denotes fully loaded vehicles/ others completed collection with less than a
full load.
-150-
-------
MISSION CANYON
SANITARY
,.Co. Sanitation Districts)
CITY OF INGLEWQOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 1
LOCATION MAP
SOUTHERN CALIFORNIA
-151-
-------
REDONDO
BEACH
, 3
*!
ix -.—n, : um-n
-"
CITY OF INGLEWOQD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 2
LOCATION MAP
LOS ANGELES AREA
-152-
-------
NO SCALE
„„„„ ROUTE 1
— — ROUTE 2
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 3
STREET MAP, STUDY AREA A
SINGLE FAMILY RESIDENTIAL AREA
-153-
-------
NO SCALE
ROUTE 3
ROUTE 4
CITY OF INGUEWOOD/U.S.P.H.S.
IWIPH STONE AND COMPANY, INC.
FIGURE 4
STREET MAP, STUDY AREA B
SINGLE FAMILY RESIDENTIAL AREA
-154-
-------
NO SCALE
ROUTE 5
ROUTE 6
ClITY OF INGLEWOOD/U.S .P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURES
STREET MAP, STUDY AREA C
SINGLE AND MULTIPLE
FAMILY RESIDENTIAL AREA
-155-
-------
LEGEND
iiT-iTi ROUTE 1
.•;.:..:. ROUTE 3
ROUTE 2
ROUTE 4
ROUTE 5
ROUTE 6
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 6
STUDY AR-EA LOCATIONS
INGLEWOOD, CALIFOFNIA
-156-
-------
1.20
1.00
0.80
"E
Z 0.60
O
O
U
0.40
0.2(
LEAST
SQUARE LINE
POINT ROUTE
M^B
2
ROUTE!
3 4
CANS (No.)
CITY OF INGLEWOOP/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
ROUTE 2
FIGURE 7
COLLECTION TIME
CANS ONLY - AREA A
-157-
-------
1.20
1.00
0.80
Z 0.60
O
I
O
o
0.40
0.20
LEAST
SQUARE LINE
POINT ROUTE
3
4
ROUTE 3
ROUTE 4
3 4
CANS (No.)
CITY OF INGLEWOOD/U.S.P .H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 8
COLLECTION TIME
CANS ONLY - AREA B
-158-
-------
1.20
1.00
0.80
Ul
Z 0.60
O
O
-------
1.20
1.00
0.8G
*E
F=
0.60
0.40
0.2C
LEAST
SQ LINE POINT ROUTE ITEM
1 GAWAND OTHER ITEMS
A 2 CANS AND OTHER ITEMS
ROUTE 1
01234
ITEMS (No.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
ROUTE 2
6 7
FIGURE 10
COLLECTION TIME
ITEMS - AREA A
-160-
-------
1.2G
1.00
0.80
c
"I
Z 0.6C
O
O
U
0.4C
0.2G
LEAST
SQ UNE POINT ROUTE ITEM
~ 3T~ CATJTAND OTHER ITEMS
O 4 CANS AND OTHER ITEMS
ROUTE 4
3 4
ITEMS (No.)
CITY OF 1NGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
ROUTE 3
RGURE 11
COLLECTION TIME
ITEMS - AREA B
-161 -
-------
1.2C
1.00
0.80
c
3
F=
Z 0.60
O
u
0.40
0.20
LEAST
SQ UNE
POINT ROUTE ITEM
~~5 5 CA~NTAND OTHER ITEMS
A 6 CANS AND OTHER ITEMS
ROUTE 6
ROUTE 5
01 2 34
ITEMS (No.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
6 7
FIGURE 12
COLLECTION TIME
ITEMS-AREA C
-162-
-------
FRIEDMAN WIDEb
CAN LINER
.REFUSED (2)
1ST & 2ND
DISTRIBUTION
(3 MONTHS EACH;
6 MONTHS TOTAL)
ST. REGIS0
BAG
-------
REFUSED 0)
1ST
DISTRIBUTION
(3 MONTHS)
ST. REGIS0
BAG
(56)c
ST. REGIS0
FREE-
STANDING
BAG
(56)
MOBIL
KEEP-,
AWAy
BAG
(43)
INTERNATIONAL0
BAG
(76)
FRIEDMAN WIDE0
CAN UNER
(94)
2ND
DISTRIBUTION
0 MONTHS)
i
t
i Paper.
Polyethylene.
Number in parenthesis designates the number of units using the system.
j
i
MOBIL
KEEP-,
AWAY0
BAG
(43)
T
T
WAGNER0
CANUNER
(44)
INT'L0
BAG
(43)
ST. REGIS0
BAG
(57)
1
1
WAGNER0
CANUNER
(94)
WAGNER0 X ^INTERNATIONAL0 WAGNER0/ ^INTERNATIONAL0
CANUNER BAG CANUNER BAG
_ 03) 02) 02) (7)
^-REFUSED 0)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
RGURE 14
BAG AND U NER DISTRIBUTION
ROUTE B4
-------
o>
Ul
INTERNATIONAL BAG
ST. REGIS0
FREE-STANDING
1ST
DISTRIBUTION
(3 MONTHS)
\
ST. REGIS0
BAG
020)
MOBIL
KEEP-s
AWAY"
BAG
(60)
FRIEDMAN WIDEb
CAN LINER
(416)
L
r
VACANT (2)
2ND
DISTRIBUTION
(3 MONTHS)
WAGNERB
CANUNER
1 ! 1 j **
• i i ,i
! i
ii i ii
7
1
\
WAGNER1*
CANUNER
001)
WAG-
NERb
CAN
LINER
(60)
INTERNATIONAL0
BAG
077)
WAGNERb
CAN LINER
012)
T
ST. REGIS0
BAG
(89)
f
' \^ ST. REGIS0 MOBILb / WAGNER1^
ST.' BAG KEEPAWAY CANUNER
REGIS 09) 08) 02)
BAG
OD
^VACANT (2)
. Paper.
Polyethylene.
Number in parenthesis designates the number of units using the system.
RGURE 15
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STUINt AND COMPANY, INC.
BAG AND LINER DISTRIBUTION
ROUTE C5
-------
ST. REGIS
FREE-STANDING
1ST
DISTRIBUTION
(3 MONTHS)
ST. REGIS0
BAG
(258)
INTER- ,
NATIONAL
(211)
MOBIL ,
KEEPAWAV
094)
FRIEDMAN WlDEb
CAN LINER
(517)
~T-
2ND
DISTRIBUTION
(3 MONTHS)
a
in
00
i/i
7
z
\
0
MOBIL"
KEEPAWAY
BAG
(43)
ST. REGIS5
BAG
(68)
UJ
S
CO
O ^
5 <
WAGNER
CAN UNER
(213)
INTER- a
NATIONAL
BAG
(177)
WAGNEF
CAN LINER
(47)
INTERNATIONAL°^WAGNERb
y.
•u
o
(/>
VACANT (2)
/" REFUSED 0)
f t
^
VACANT (2)
REFUSED (1)
BAG
(43)
MOBIL X, WAGNER N INTER-
CAN UNER KEEPAWAr1 CAN UNER NATIONAL0
BAG BAG
(73)
(38)
(56)
02)
b Paper.
Polyethylene.
Number in parenthesis designates the number of units using the system.
NOTE: See Figure 13 for the 3rd Distribution Summary.
CITY OF 11NGLEWOOD/U.S .P .H S
RALPH STONE AND COMPANY, INC.
FIGURE 16
BAG AND LINER DISTRIBUTION SUMMARY
ROUTES Al, B4, C5
-------
1.60
1.40
1.20
1.00
lu
5 0.80
8
0.60
0.40
0.20
DATE POINT ITEM
10/22/68 o PRIOR TO BAG DISTRIBUTION
5/20/69 D DURING BAG USE
ROUTE Al—CANS AND ITEMS
(10/22/68)
ROUTE Al—BAGS AND ITEMS
(5/20/69)
— n—°
i i i i
I
I
0.2 0.5 1 2 5 10 20 30 40 50 60 70 80 90 95 98 99
PERCENT OF STOPS REQUIRING TIME EQUAL TO OR LESS THAN INDICATED TIME
99.8
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 17
COLLECTION TIME
DISTRIBUTION, ROUTE Al
-------
00
2.00
1«w\
.80
1.60
1.40
£ 1.20
^^^
UJ
i i.oo
Q.
o
fc 0.80
i/i
0.60
0.40
0.20
Q
r DATE POINT ITEM
_ 10/22/68 n PRIOR TO BAG DISTRIBUTION Q ^
5/20/69 o DURING BAG TESTS ON ROUTE Al ^^
~ D^ ^^
°X ^
D S3
ROUTE A2— CANS AND ITEMS X V^
(10/22/68) ^^^V X
c/ /
c/o/
y0/'^-^ ROUTE A2— CANS
dV AND ITEMS
& (5/20/69)
_ oo
s
- da
X
QO
X
xxQ°
^^
^m __ Q^J"'
U *^^
i i i i ii i i i i i i i ii ii i
0.2 0.5 1 2 5 10 20 30 40 50 60 70 80 90 95 98 99 99.8
PERCENT OF STOPS REQUIRING TIME EQUAL TO OR LESS THAN INDICATED TIME
FIGURE 18
CITY OF INGLEWOOD/U.S.P.H.S. COLLECTION TIME
RALPH STONE AND COMPANY, INC.
DISTRIBUTION, ROUTE A2
-------
1.2
1.0
0.8
c
'§
Z0.6
U
0.4
0.2
LEAST
SQ LINE POINT ROUTE ITEM
1 BAGS ONLY
2 CANS ONLY
ROUTE 2
ROUTE 1
2345
BAGS OR CANS (No.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 19
COLLECTION TIME
BAGS AND CANS - AREA A
-169-
-------
i.s
i.c
-------
.
1.0
.(
zo.4
o
8
0.'
0.2
LEAST
SQ LINE POINT ROUTE ITEM
....^_. n 5 BAGS ONLY (PAPER AND POLYETHYLENE)
A 6 CANS ONLY
ROUTE 6
ROUTE 5
t
2 3 4 5
BAGS OR CANS (No,)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 21
COLLECTION TIME
BAGS AND CANS - AREA C
-171-
-------
1.2
1.0
0.8
LU
Z0.6
O
u
O
u
0.4
0.2
LEAST
SQ LINE
POINT ROUTE ITEM
1 BAGS AND OTHER ITEMS
2 CANS AND OTHER ITEMS
X
ROUTE 2
X
X
ROUTE 1
01234
ITEMS (No.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 22
COLLECTION TIME
ITEMS - AREA A
-------
1.2
1.0
0.8
Z0.6
O
t3
8
0.4
0.2
LEAST
SQ LINE
POINT ROUTE ITEM
A 3 CANS AND OTHER ITEMS
D 4 BAGS AND OTHER ITEMS
ROUTE 3
ROUTE 4
01234
ITEMS (Nd.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 23
COLLECTION TIME
ITEMS - AREA B
- 173-
-------
1.0
0.8
LU
U
o
u
0.4
0.2
LEAST
SQ LINE POINT ROUTE ITEM
_....._ a 5 BAGS AND OTHER ITEMS
—— A 6 CANS AND OTHER ITEMS
ROUTE 6
ROUTE 5
3 4
ITEMS (No.)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 24
COLLECTION TIME
ITEMS - AREA C
- 174-
-------
O STOPS HAVING GREATER THAN OR EQUAL TO
THE INDICATED NUMBER OF CANS (%)
3 o 3 £ 8 8 8
HAVING GREATER THAN OR EQUAL T
IE INDICATED NUMBER OF BAGS (%)
8 fe 8 8 J
l/> 0.
£ o
CITYC
100
1
100
75.6
2
82.1
ROUTE A2
40.9
22.0
4.7
1.0 0.0
34567
CANS (No.)
ROUTE Al
44.2
20.0
Ilr6
5.3 5.3
1 . 1
1234567
BAGS (No.)
FIGURE 25
DF INGLEWOOD/U.S.P.H.S. DISTRIBUTION OF CANS AND BA(
RALPH STONE AND COMPANY, INC.
AT COLLECTION STOPS
-175-
-------
O i J
STOPS HAVING GREATER THAN OR EQUAL T<
THE INDICATED NUMBER OF ITEMS (%)
N> -N O* 00 C
0 0 0 0 0 <
100
85.6
58.6
ROUTE A2
36.5
17.1
9.5
4.1
1 234567
ITEMS (No.)
TOO
il80-
, i^
ssi
^ z>
0£. Q 40
O "J
z&
-------
0.60
0.50
0.40
uj
Z0.30
o
u
0.20
0.10
LEAST
SQ LINE POINT ITEM
_ A PAPER BAG (MEAN VALUES)
© POLYETHYLENE BAG (MEAN VALUES)
PAPER
POLYETHYLENE
o
1
1
234
NUMBER OF BAGS PER STOP
CITY OF INGLEWOOD
RALPH STONE AND
)OD/U.S.P.H.S.
COMPANY, INC.
FIGURE 27
COLLECTION TIME FOR BAGS
ROUTE Al
-177-
-------
0.80r-
0.70 —
0.60
0.50-
c
Z0.40
o
u
0.30-
0.20-
0.10 —
LEAST
SQ LINE POINT
ITEM
-- " A PAPER BAG (MEAN VALUES)
- o POLYETHYLENE BAG (MEAN VALUES)
©
POLYETHYLENE
o
o
1
I
I
234
NUMBER OF BAGS
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 28
COLLECTION TIME FOR BAGS
ROUTE B4
-178-
-------
TEST AREA, l,000sqft
SIDEWALK
CURB
\
200ft
3ft
2ft
STREET
NO SCALE
CITY OF INGLEWOOD
RALPH STONE AND
)OD/U.S.P.H.S.
COMPANY, INC.
FIGURE 29
CONFIGURATION OF TYPICAL TEST
AREA FOR LITTER OBSERVATIONS
-179-
-------
o
Z
26
25
24
22
?0
18
16
14
12
10
8
6
4
2
0
BEFORE WASTE COLLECTION
AFTER WASTE COLLECTION
0-2 2-4 4-6 6-8
8-10 10-20 20-30 30-40 40-50 50-60 60-70
LITTER SURFACE SIZE (sq In.)
ClITY OF INGLEWOOD/U. S .P. HI.. S.
RALPH STONE AND COMPANY, INt.
RGURE 30
LITTER DISTRIBUTION
-------
40
36
32
28
24
20
16
12
8
4
•
•
•
•»—
^^
d BEFORE WASTE COLLECT ON
|~~1 AFTER WASTE COLLECTION
MMM!
1
•MM
S
^n
nbi rn
O •-' C4 CO ^ >0
j!SJ3SSSo!>ele>J.^co4
MAXIMUM DIMENSION (In.)
CITY OF 1NGLEWOOpAl. S .P. H. S.
RALPH STONE AND COMPANY, INC.
FIGURE 31
DISTRIBUTION OF LITTER
BY MAXIMUM DIMENSION
-181-
-------
Note: Enumerated restaurants are identified in Taole 28.
CITY OF INGLEWOOD/U.S.P.H.S.
'RALPH ST6NEAND COMPANY, INC.
FIGURE 32
LOCATION OF RESTAURANTS
TESTING BIN LINERS
-182-
-------
30
s
«/»
O
o
D
O
3
25
20
15
10
o TOTAL
1.5 mil POLYETHYLENE
2.5 mil POLYETHYLENE
9 PAPER
JAN ' FEB ' MAR ' APR ' MAY ' JUNE ' JULY '
MONTH (1970)
FIGURE 33
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC
CONTINUED BAG USE, AREA B4
(326 SINGLE FAMILY UNITS)
-183-
-------
35
30
25
O
o
20
15
o
z
=1
10
TOTAL
1.5ml! POLYETHYLENE
* 2.5 mil POLYETHYLENE
PAPER
JAN ' Fii ' MAR ' APR ' MAY ' JUNE ' JULY '
MONTH (1970)
CITY OFjNGLEVyOpp/U.S.P.H.S.
RALPH STONE AND COMPANY, INC,
FIGURE 34
CONTINUED BAG USE, AREA C5
(85 SINGLE FAMILY UN ITS,
102 APARTMENTS)
-184-
-------
30 r-
25
8 20
O
z
I
15
o
z
3 10
1U
HOMES
APARTMENTS
JAN ' FEB ' MAR ' APR ' MAY ' JUNE ' JULY '
MONTH (1970)
CITY OF INGLEWOOD
RALPH STONE AND
)OD/U.S.P.H.S.
COMPANY, INC.
FIGURE 35
TOTAL BAG USAGE IN APARTMENTS
AND SINGLE FAMILY UNITS,
AREAC5
(85 SINGLE FAMILY UNITS,
102 APARTMENTS)
-185-
-------
LEGEND:
DISTANCE FROM HOPPER CENTER (ft)
o w o* «o ro Ut
LEVELS OF EQUAL DUST
h CONCENTRATION
500 V 40 GAL HOUSEHOLD CAN
1,000 S^^. * CENTER OF RECEIVING HOPPER
2,POO o^ x,^ 0 SAMPLE POINTS, DUST CONCEN-
S'OOO «xOx ^\X TRATIONS IN PARTICLES/SQ IN.
~ ' xx\X\ XCX ' DIRECTION FOR EMPTYING CAN
^' 10,000 »x XC\\ x N^ MAXIMUM DUST CONCENTRATION
. _^ 15,000 «x xx X\N\\ \X\
g 20,000 OXSNN \\x \^x
S \\ \\\\ N"^
. 1335,000 ox \ \ \ \ o \ N \
Q \\\\?\\ \\
° 60,000 «N \ \ \ \ 1 \ \ \
77,500 o*>^ N \\ 1 ' | 1 \ \
*,**-'; >;/// / i \
-------
POLYETHYLENE
P
AXIAL
LOAD
Tin.
RADIUS
LONGITUDINAL
GAUGE LENGTH 1/4 in.
TRANSVERSE GAUGE
LENGTH 1/4 in.
PAPER
1 in.
f
1 in.
1
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 37
TEST SPECIMEN
DIMENSIONS
-------
(in./in.)
-It*
POLYETHYLENE
GAUGE LENGTH
PAPER GAUGE LENGTH (L)
TRUE AVERAGE
PAPER STRAIN PRO FILE
POLYETHYLENE
STRAIN PRORLE
POSITION
POLYETHYLENE
PAPER
TEST SPECIMEN CONFIGURATIONS
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH SToKib AKit) COMPANV, INC.
FIGURE 38
DISTRIBUTION OF STRAIN
-'•38-
-------
24
c 20
s
^ 16
's»
X
in
a
a
o A
y*
04
pyfc
X = FAILURE
CHASE DRAWSTRING
(2.5 mil)
0 1.0 2.0 3.0 4.0 5.0 6.0
STRAIN, c (in./in.)
24
<••*
M
ji 20
*x,
N& 16
o
"x 12
^ 8
l/>
\ft
LU ^
^^ 4
c/)
24
! A/D NE' 20
OB ^ 51
AB>^ cT 16
Aj^^a 'o
r*^ MOBILKEEPAWAY ~ 12
(2.5 mil)
b» 8
> «^
"? j
I uj 4
8 a:
CO
a «•**
o ^^ o
OS D
O /A D
9&
^ a
cfc FRIEDMAN NARROW
$ (2.5 mil)
J
11 i . . i
0 1.0 2.0 3.0 4.0 5.0 6.0
STRAIN, €(in./in.)
CITY OF INGLEWOOD/U ,S .P. H .S.
RALPH STONE AND COMPANY, INC.
0 0.5 1.0 1.5 2.0 2.5 3.0
STRAIN, €(in./in.)
FIGURE 39
STRESS-STRAIN CURVES,
POLYETHYLENE BAG SPECIMENS
-189-
-------
24 f
20
2 12
OX
FRIEDMAN WIDE
(3.0 mi I)
0 1.0 2.0 3.0 4.0 5.0 6.0
STRAIN, € (in./in.)
X = FAILURE
24
WAGNER
(3.5 mi I)
0 1.0 2.0 3.0 4.0 5.0 6.0
STRAIN, t (in./in.)
CITY OF INGLEWOOD/U.S .P.H .S.
RALPH STONE AND COMPANY, INC.
40
STRESS-STRAIN CURVES,
POLYETHYLENE CAN
LINER SPECIMENS
-190-
-------
24 r
o
o
8
X FAILURE
LONGITUDINAL SPECIMEN
DA TRANSVERSE SPECIMEN
o 45° SPECIMEN
i i i i L
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
STRAIN, € (?n./in.)
4 CU YD BIN LINER
(2.0 mtl)
24 r *£ O
v -* 5 '
~.~* . ° /
X FAILURE
wA LONGITUDINAL SPECIMEN
OD 45° SPECIMEN
o TRANSVERSE SPECIMEN
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
STRAIN^ (!n./ln.)
3 CU YD BIN LINER
(2.0mfl)
CITY OF INGLEWOOD
RAIPH STONE AN DCO
/U.S.P.H.S.
MPANY, INC.
FIGURE 41
STRESS-STRAIN CURVES,
POLYETHYLENE BIN LINER SPECIMENS
-191-
-------
12
c^lO
is
x
^
o
CO
CO
E 2
7
INTERNATIONAL
10 20 30 40 50 60 70 80
STRAIN,e,xl03(5n./in.)
X = FAILURE
CM ^ CM
>i2 . A^-*"Q ° Si2
„"" A^^° ° n~
*2 8 • A^S'^5 *2 8
x, r
0- 4 • ST. REGIS 1 4
g (OUTSIDE LAYER) g
o
"yO^A ST. REGIS
K A (INSIDE LAYER)
i
" " 3 9 15 21 27 ^ " 3 9 15 21
^
.x-A
i
27
STRAIN, £, xlOJ (In./in.)
STRAIN, t
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 42
STRESS-STRAIN CURVES,
PAPER BAG SPECIMENS
LONGITUDINAL CUT
-192-
-------
WIDTH OF TEST SPECIMEN
(1/2 in. FOR POLYETHYLENE)
(1 in. FOR PAPER)
NO SCALE
PINHOLES
TEST SPECIMEN
CITY OF INGLEWOOD,
RALPH STONE AND CO.
)/U.S.P.H.S.
iMPANY, INC.
FIGURE 43
TYPICAL PINHOLE
TEST SPECIMEN
-193-
-------
CLAMP
COMPRESSION
CAGE
SPECIMEN TEST
SURFACE
SPECIMEN
HOLDER, METAL
TUBE
CITY OF INGLEWOQD/U.S.P.H.S.
RALPH S"t6N£ AND COMPANY, INC.
FIGURE 44
APPARATUS FOR
PUNCTURE TESTS
-194-
-------
STRESS, a,= l,600_Jk_
2
n.
___--a ----------- Q ENVIRONMENTAL SPECIMENS
CONTROL SPECIMEN
CONTROL DATA POINTS
ENVIRONMENTAL DATA POINTS (CLIMATIC RANGES)
20
30
40
50 60
TIME (hrs)
70
80
90 100
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 45
LONGITUDINAL STRAIN-TIME CURVES,
FRIEDMAN POLYETHYLENE BAG
(2.50111), NARROW
-------
0.50
0.40
^0.30
«.
z
0.20
O.TO
STRESS, P , = 1,600
in.-
-Q ENVIRONMENTAL SPECIMENS
CONTROL SPECIMEN
o = CONTROL DATA POINTS
* D = ENVIRONMENTAL DATA POINTS (CLIMATIC RANGES)
10
20 30
40 50 60
TIME (hrs)
70
BO
90 100
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 46
TRANS VERSE STRAIN-TIME CURVES,
FRIEDMAN POLYETHYLENE BAG
(2.5 mil), NARROW
-------
3.00
2.50
2.00
x
«u
1.50
1.00
a a
o
STRESS, <7,= 1,143 Jk
in.
Q Q
ENVIRONMENTAL SPECIMENS
CONTROL SPECIMEN
0.50
ol
f) Q ff ** 0 —
o = CONTROL DATA POINTS
* Q • ENVIRONMENTAL DATA POINTS
) 10 20 30 40 50
TIME
CITY OF INGLEWOOD/U.S.P.H.S.
60
(hit)
70
(CLIMATIC RANGES)
• •
80 90
FIGURE 47
LONGITUDINAL STRAIN-TIME CURVES,
RALPH STONE AND COMPANY, INC.
WAGNER POLYETHYLENE LINER (3.5 mil)
-------
o
a
£ 75
z
^
o
01
§
5 50
l/>
0
3
uj 25
O
H-
Ul
e
°- o
\
\
\ i
^D
\
\
V
\
\
\
\
\
20
U* (in.-lb/in.2)
30
40
Point 1. Bac«d on combined field data for Mal»H Keepaway and Friedman Narrow bags.
Point 2. BaMdon combined field data Far Friedmcu Wide and Wagrwr linen.
Point 3. Assuming 100 percent failure occurs at zero U*.
CITY OF 1NGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 48
PERCENT FAILURE OF
POLYETHYLENE BAGS VERSUS U*
-198-
-------
10,000
8,000
6,000
4,000
2,000
0.001 0.002 0.003
THICKNESS (in.)
0.004
CITY OF INGLEWOOD
RALPH STONE AND
OD/U.S.P.H.S.
COMPANY, INC.
FIGURE 49
ACCEPTABLE VALUES OF U
AS A FUNCTION OF
POLYETHYLENE BAG THICKNESS
(SHADED REGION IS UNACCEPTABLE)
-199-
-------
COLLECTION TIME (man minutes per ton)
oo o1 8 1
• • • • 9
o o o o o
ASSUMPTIONS:
Non-Productive Time, K =
One-Way Drive Time, Route to Disposal, B -
Mean Amount of Waste Per Stop, Q :
Crew Size, CS =
t = 0.74 m?n (G
^•••••••••••••••v
i i i i
kNS)
h^,_
^^-^
t- 0.58 min (BA(
i I i i
isT*" — *,^
i i i i
^ 100 min
= 50 min
= 60 Ib
1 MU.R
• man
•^
i I i i
20 25 30 35 40
TRUCK VOLUM€(cu yd) F|GURE ^
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
CAN-BAG COLLECTION TIMES
ONE-MAN CREW
-200-
-------
140.0
100.0
o
a.
8
3
"i
c
Z
O
I—
u
50.0
O
u
10.0
0.0
ASSUMPTIONS:
Non-Procfo
One-Woy Drive Time, Route
Mean Amount of Was
\,
•^
I i i i
t=0.69min(C/
t=0.53m!n (BA
I i i i
ctiveTlme, K
to Disposal, B
te Per Stop, Q '
Crew Size, CS =
,NS)
\
\
GSJ M
i i i i
= 100 min
- 50 min
= 60 Ib
= 2 men
'****%%%****^
I I I 1
20
40
25 30 35
TRUCK VOLUME (cu yd) p|GuRE ^
CITY OF INGLEWOOD/U.S.P.H.S. CAN-BAG COLLECTION TIMES
RALPH STONE AND COMPANY, INC. TWO-MAN CREW
-201-
-------
140.0
100.0
o
o
QL
8
3
c
'§
c
Z
O
Q
Crew Size, CS
1 1 1 1
*NS)
mrnrmn ••••••»•••••
rm?7(BA"GSy""
= 1 00 min
= 50 min
= 60 Ib
= 3 men
! 1 1 I
20
25 30 35
TRUCK VOLUME (cu yd)
40
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 52
CAN-BAG COLLECTION TIMES
THREE-MAN CREW
-202-
-------
0.50
0.40
So.30
z
O
C
3
o
u
).20
0.10
ASSUMPTIONS;
Non-Productive Time, K = 100 min
One-Way Drive Time, Route to Disposal,.. B - SO min
Mean Amount of Waste Per Stop, Q = 60 Ib
Crew Size, CS = 1 man
i i i
f=-0.74 min (CANS)
t= 0.58 min (BAGS)
i i i
J 1
1 I I I
20
25 30 35
TRUCK VOLUME (eu yd)
CITY OF INGLEWOOD,
RALPH STONE AND CO
)/U.S.P.H.S.
iMPANY, INC.
40
FIGURE 53
CAN-BAG COSTS
ONE-MAN CREW
-203-
-------
0.50
0.40
i
S
0.30
LU
LLJ
in
o
Z
O
o
u
0.10
One-Way C
M(
.—.«•—•'
,»•«••""
i I I I
ASSUMPTIONS:
Non-Productiv* time, K
)rive Time, Route to Disposal, B
>an Amount of Waste Per Stop, Q
Crew Size, CS
t = 0.69min(CA
r»»»-»— - m-^MT*.
^ ^ m ,mmf^"^'^*m
t = 0.53 mln (BA<
i i i i
s4S)
*»»f.
™*i
^mffm't
3ST
i i i i
= 100 min
50 min
- 60 Ib
= 2 men
1111
20
25 30
TRUCK VOLUME (cu yd)
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
35 40
FIGURE 54
CAN-BAG COSTS
TWO-MAN CREW
-204-
-------
0.50
0.40
c
o
. 30
10
o
z.
q
IH-
u
o
u
0.20
0.10
\
\
5
r
t = 0.58 min (C/
~\1
[
^
^NS)
'\ s "
\
'\
. •»
0.41 min (BAGS
U"**"*M.— — — ""
^^•^^
ASSUMPTIONS:
Non-Productive Time, K
One-Way Drive Time, Route to Disposal, B
Mean Amount of Waste Per Stop, Q
Crew Size, CS
i i i i
i i i i
1 1 1 1
f
= 1 00 min
50 min
60 Ib
= 3 men
i i i i
20
25 30 35
TRUCK VOLUME (cu yd)
CITY OF INGLEWOOD,
RALPH STONE AND CO
>/U.S.P.H.S.
'MPANY, INC.
40
FIGURE 55
CAN-BAG COSTS
THREE-MAN CREW
-205-
-------
420
400
<350
L^
(X
UJ
a..
ffl
Cf
LLJ
fcO
LL
o
1
J?.
300
250
ASSUMPTIONS;
Non-Productive Timer K = 100 min
One-Way Drive Time, Route to Disposal, B = 50 min
Mean Amount of Waste Per Stop, Q = 60 Ib
Crew Size, CS = 1 man
20
25 30
TRUCK VOLUME (cu yd)
CITY OF INGLEWOOD/U.S.P.ti.S.
RAIPH STONE AND COMPANY, INC.
35 40
FIGURE 56
CAN-BAG SERVICES
ONE-MAN CREW
-206-
-------
14.0
10.0
o
c
j>
~o
O
u
z
o
_
O 5
u •
1.0
0.0
ASSUMPTIONS;
Non-Productiv* lime, K = 100 min
One-Way Drive Time, Route to Disposal, -B = 50 min
Mean Amount of Waste Per Stop, Q = 60 Ib
Crew Size, CS = 1 man
I I I I
20
V
t= 0.74 mm (CANS)
t= 0.58 min (BAGS)
I I I
I I I
25 30
TRUCK VOLUME (cu yd)
I I I I
CITY OF INGLEWOOD,
RALPH STONE AND CO
>/U.S.P.H.S.
MPANY, INC.
35 40
FIGURE 57
CAN-BAG COSTS
ONE-MAN CREW
-207-
-------
W • *J\J
0.40
c
o
i'l
_u
~
(_>
>0.30
"o
T3.
U.'
»,,
or
iid
o
>;
^0. 20
£
*jx
L'j
0.
IO
0
ij
9.10
0
ASSUMPTIONS:
Non -Product iv« Time, K.
Mean Amount of Wast* Per. Stop, Q
Crew Size , CS
Stop Time Plus Travel Between Stops, t
_-— —
,- ""
— —— "^^p^^^^"*^^*
WHERE B =
iiii
B=50
^
^ •
B=30
.,
B= 10
DISPOSAL SITE 0
iiii
— ~— — ^
_—-^
^^^f^
NE WAY TRAVEL
iiii
= 100 min
= 60 Ib
= 1 man
- 0.74 min
=:r^^
. TIME (min)
iiii
20
25 30 35
TRUCK VOLUME (cu yd)
40
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
FIGURE 58
EFFECT OF DISPOSAL TRAVEL TIME
ON COSTS PER SERVICE
-208-
-------
0.50
0.40
o
0.30
o
TJ
y
Of.
UJ
I/)
0.20
UJ
Q.
O
u
0.10
One-Way
• • -M«
StopT
==:
WHERE K *
\ \ i \
ASSUMPTIONS:
Drive Tfm*, Route to DIspMd, B
Kin Amount of~Wasfe Per -Stop* Q
Crow Strt, CS
ime Plus Travel Between Stop*> t
K = 100 mfn
— —
K = 75 mm
••••i^""^^" ^""^ "
-
K = 50 mln
TOTAL NON-PRC
i i i i
f
— ^
=i^
3DUCTIVEWORK
i i i i
= fiOfnin
• 60 Ib
^ 1 man
= 0.58min
__
TIME (min)
i i i i
20
25
30
35
40
RAIPH STONET^ND COi
TRUCK VOLUME (cu yd)
>/U.S.P.H.S
iMPANY, INC.
CITY OF INGLEWOOD/U.S.P.H.S. EFFECT OF NON-PRODUCTIVE
FIGURE 59
: NON-PRC
WORK TIME ON COSTS PER SERVICE
-209-
-------
0.50
0.40
n
*••
-*.
U
- 0.30
0.20
U
O-iO
w
One-Way
Stop Ti
Q=60^**^
*•"•
Q=50
HERE Q = MEAN
iiii
ASSUMPTIONS:
Non -Product! v» Time, K
Drive Time, Route to Disposal, B
Crew Size* CS
me Plus Travel Between Stops , t
Q = 70
—— — SSSSBM
QUANTITY OF S
iiii
—
-------
B
A. Time and Motion Sequential Timer Equipment.
B. St. Regis Paper Bag with St. Regis Holder.
C. International (Garbax) Bag with International Holder.
D. Mobil (Flamegard) Polyethylene Bag with Mobil Holder,
E. Mobil (Luxriliner) Polyethylene Can Liner Installed.
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
PLATE 1
PHOTOGRAPHS
-211-
-------
c.
D,
c
Collector Loading Polyethylene Bag by Holding Handle Provided by Closure
with Paper-Covered Wire.
Bin with a Slipped Liner.
B and K Precision Sound Level Meter.
Typical Waste Picked Up for Litter Index.
St. Regis Paper Bag Rotted from Resting on Damp Ground (time period unknown),
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
PLATE 2
PHOTOGRAPHS
-212-
-------
A. Closed Polyethylene Bags Ready for Collection,
B. Street with Paper Bags on Day of Collection.
C. Conventional Trash Cans.
D. Street with Cans on Day of Collection.
CITY OF INGLEWOOD/U.S.P.H.S.
RALPH STONE AND COMPANY, INC.
PLATE 3
PHOTOGRAPHS
-213-
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APPENDIX A
GLOSSARY
Bag—plastic or paper bags specifically Intended for containment of solid waste
materials. These bags normally have a capacity greater than 20 gal.
Bag system—the bag system refers to the manufacturer's complete system for use of the
bag. This may include the disposable bag and tie only in the case of a liner,
or the disposable bag, tie, and a suitable permanent type holder in other
instances.
Bin—solid waste container of one cubic yard, or larger, of capacity normally used in
apartment houses or commercial and industrial establishments for the storage of
solid waste.
Can—hard container.
Combined solid waste—household solid waste including wrapped garbage and yard
trimmings.
Cost per unit capacity—C* = relative cost; cost per unit volume of bag (or, alternatively,
of appropriate cost per unit of useful capacity, or cost per unit of solid waste
capacity).
Disposable container—bags.
Energy absorption—u* = ut, where t = measured thickness of test specimen, u = strain
energy; total maximum energy absorption capability per actual material cross
sectional area.
Hard containers—rigid or semi-rigid metal, wood, or plastic containers used for the
storage of solid waste.
Holder—a frame for the support of the disposable bag.
Item—any separate, individual piece of solid waste, container, bag, box, bundle,
etc., placed at a collection stop.
Stop—a location where solid waste is placed for collection by the collector. The stop
may contain solid waste from a single unit (such as a single family home) or from
many units (such as a large apartment house).
-214-
-------
Strain—eu= ultimate strain; strain at failure in uniaxial loading.
Strain energy—u = strain energy, or energy per unit volume up to the point of failure
in uniaxial loading; this corresponds to the total area under the stress-strain
curve; u is thus a measure of ability of the material to absorb energy without
failure.
Stress--Oy = ultimate stress; stress at failure in uniaxial loading; force -i-cross sectional
area.
Unit—a place of residence for one person or family; dwelling unit.
-215-
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APPENDIX B
STANDARDS FOR PAPER AND POLYETHYLENE BAGS
Two standards are in existence at present covering bags for solid waste storage;
one relates to polyethylene bags and the second Is at present a proposed standard for
paper bags. A short summary of each is presented.
1. Polyethylene Bags. The standard essentially sets out allowable material
composition, material performance, bag characteristics, and bag performance.
a. Resin. Film for bags shall be manufactured from polyethylene or ethylene
copolymer resin.
b. Film. Film produced from the resin specified in Item (a) shall comply with
the following:
Dart impact strength at fold and seals shall not be less than 60 grams when
tested in accordance with ASTM D-1709, Method A.
The nominal gauge of the film shall be 1.5 mil with point-to-point variation
not to exceed ±20 percent.
NOTE: This requirement is not intended to preclude the use of nominal wall
thickness in excess of 1.5 mil; however, the ±20 percent mentioned shall apply to
said nominal wall thickness.
The film shall be capable of incineration under normal municipal incinerating
practices. (See Incinerator Guidelines - 1969, U.S. Public Health Service.)
c. Dimensions. The bags shall have a minimum circumference of 60 in. and
a minimum inner dimension of 37 in.
d. Slip Coefficient. The bags shall be readily opened by hand and shall
have a slip coefficient between 0.1 and 0.25, when tested in accordance with ASTM
D-1894.
e. Heat Seal. Any heat seal shall withstand a ten-minute tensile loading of
1 Ib per inch of seal without failure.
National Sanitation Foundation Standard Number 31 Relating to Polyethylene
Refuse Bags (April 1970).
-216-
-------
f. Drop Resistance. Bags shall withstand a drop of five (5) feet onto smooth
concrete when filled to a total weight of thirty (30) pounds with material having a
weight density of fifteen (15) pounds per cubic foot. The bag shall be securely closed
with a twist tie.
g. Weight. The bags, exclusive of packaging and ties, shall have a
minimum weight of 105 Ib per 1,000 bags.
h. Closures. Each package of bags, intended for retail sales, shall contain
an equal quantity of five (5) inch wire tie closures or their equivalent.
2. Paper Bags. The proposed standard sets out minimum requirements for bag
and material performance together with allowable alternate materials and fabrication.
a. Papers. Sacks shall be fabricated either wholly from non-extensible or
from extensible WET STRENGTH Kraft paper, as specified, and shall be fabricated to
meet the minimum paper test requirements of Table Bl or B2.
b. Adhesives. Adhesives used for seams and closures shall be water-resistant
types and shall meet the requirements of the current Federal Specification UU-S-48.
c. Tape. The tape used on the ends of sewn sacks shall be 2 1/8 in. wide
with a 1/8 in. minus tolerance and an unlimited plus tolerance, and shall be made
from Kraft paper, non-extensible, extensible, or creeped having a basis weight of
not less than 70 Ib per 3,000 sq ft.
d. Thread. The stitching on the ends of sewn sacks shal I be not less than
12/5 cotton needle thread and 12/4 cotton looper thread, or rayon THREAD OF
EQUIVALENT STRENGTH.
e. Markings. Paper used in these sacks shall be distinctly marked for
identification by longitudinal stripes spaced not less than 2 in. nor more than 10 in.
on centers across the paper width, and each stripe shall be not less than 1/8 in. in
width. Markings shall appear on the external surface of the sack.
f. Performance. The sack shall withstand a drop of five (5) feet onto smooth
concrete when filled to a total weight of forty (40) pounds with a material having a
weight density of fifteen (15) pounds per cubic foot. Sacks shall be closed by crimping,
tying, or any suitable means to prevent spillage of contents during testing.
g. Physical Requirements. The minimum physical requirements are given in
Tables Bl and B2.
Proposed National Sanitation Foundation Standard for Paper Refuse Sacks.
-217-
-------
H. Tests. Tests shall be conducted in accordance with the TAPPI standard
methods listed below except as noted above, and the CURRENT Federal Specification
UU-S-48.
TAPPI0 Standard Method
Conditioning T 402
Tensile Breaking Strength T 404
Basis Weight T 410
Wet Tensile Breaking Strength T 456
Tensile Energy Absorption, Wet and Dry T 494
Water Resistance Test UU-S-48
, Technical Association of Pulp and Paper Industry.
Wet tensile strength and wet tensile energy absorption are to be determined
by using one-inch width specimens that have been immersed in water for two hours at
73°F±3.5°F.
-218-
-------
TABLE Bl
TEST REQUIREMENTS: NON-EXTENSIBLE KRAFT
Lot Average Total Paper Test Requirements
Non-Extensible Kmft Paper
Tensile
Sack
Construction
Number0
(non-extensible
Kraft paper)
4
Minimum Total
Sack Capacity
(cuft)
4.5
Nominal
Basis Weight
(lb/3,000
sqft)
100
Minimum
Basis Weight
(lb/3,000
sqft)
95.0
Dry
CD
(Ib/In.)
34.0
Total
MD+CD
(Ib/in.)
95.0
b
Wet
CD
(Ib/tn.)
9.0
Sack construction number 4 corresponds with sack construction number 4 in the latest issue of National Refuse
Sack Council, Inc., "Sepcification Sacks, Paper, Refuse".
b Wet tensile strength and wet tensile energy absorption are to be determined by using one-inch width specimens
that have been immersed in water for two hours at 73°F ±3.5°F.
MD - Machine Direction
CD = Cross Direction
-------
TABLE B2
TEST REQUIREMENTS: EXTENSIBLE KRAFT
Lot Average Total Paper Test Requirements
Extensible Kraft Paper
Tensile Energy Absorption
Sack
Construction
Number0
(extensible
Kraft paper)
4-X
Minimum Total
Sack Capacity
(cuft)
4.5
Nominal
Basis Weight
(lb/3,000
sqft)
90
Minimum
Basis Weight
(lb/3,000
sqft)
95.5
CD
(ft-lb/
sqft)
9.3
Dry
Total
MD±CD
(ft-lb/
sqft)
30.8
Wet
CD
(ft-lb/
sqft)
2.7
Sack construction number 4-X corresponds with sack construction number 4-X in the latest issue of National
Refuse Sack Council, Inc., "Specification Sacks, Paper, Refuse".
° Wet tensile strength and wet tensile energy absorption are to be determined by using one-inch width specimens
that have been immersed in water for two hours at 73°F ±3.5°F.
MD = Machine Direction
CD = Cross Direction
-------
APPENDIX C
1. SPECIFICATIONS FOR BAG AND HOLDER PURCHASES
Subject: Request for Bids - Supplying Refuse Bags for Pilot Studies in the
City of inglewood, California
Gentlemen:
We are ready to solicit bids from interested firms for the manufacture of a
limited number of plastic and paper bags for use In the pilot study activities. Both
plastic and paper bags will be tested under actual field conditions for a period of six
months.
The attached specification is included to define requirements for bags to be
supplied. Your bid should be based on the manufacture and* delivery of the specified
number of plastic or paper bags F. O.B. the City of Inglewood corporation yard
located at 444 N. Eucalyptus, Inglewood, California. A delivery date on or before
April 10, 1969 Is required.
Public relations Is considered an important aspect of the study and the City
wishes to promote voluntary use of the bags by the resident to the maximum degree
possible. The prospective bidder is requested to submit as a part of his bid an
indication of the support the firm is willing to commit during the eight month test
phase in terms of personnel, billboards, local newspaper, radio and television
advertising to assist the City of Inglewood in promoting the use of bags on a voluntary
basis. Of particular importance will be the appearance of firm personnel before
service and citizen groups, presentation of promotion films and special cooperation
with local merchants in advertising and saturation marketing of bags.
Deadline for receipt of bids is 11:00 a.m. on March 10, 1969. No bid will
be considered after this date. Please indicate your delivery schedule.
Additionally, in order for the City to evaluate economic relationships, please
indicate the following along with your regular bid.
A. Unit cost for car-load quantities of bags to meet the attached
specification:*
B. Added unit cost for single uniform bag color.
C. Added unit cost for one-color printing on the bag.
-221-
-------
-2-
Thcmk you for your continuing interest in the City of Inglewood bagging study.
Very truly yours,
William F. Farnam
Director of Public Works
WF:RS:sm
Attachments
-222-
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APPENDIX C
2. SPECIFICATION *68-30 FOR PAPER BAGS FOR SOLID WASTE
I. SCOPE
This specification covers the minimum requirements for new and unused paper
refuse bags for containment of residential refuse in the City of Inglewood, California.
II. MATERIAL REQUIREMENTS
A. Paper. Paper refuse bags shall be fabricated wholly from wet-strength
extensible or wet-strength flat Kraft paper.
B. Adheslves. Adhesives used for seams and closures shall be water-resistant
types and shafl meet In* requirements of Federal Specification UU-S-48D, paragraph
3.1.2.
C. Tape. Unless otherwise specified, the rape used on sewn ends of bags shall
be 2 1/3 in. wide (1/8 in. minus tolerance and unlimited plus tolerance), and shall be
made from wet-strength (extensible) Kraft paper having a basis0 weight of not less than
70 Ib.
D. Thread. The stitching on the ends of sewn bags shall be not less than 12/5
cotton needle thread and 12/4 cotton looper thread, or other thread of equivalent
strength.
III. PHYSICAL REQUIREMENTS
A. Paper. The specified values for the paper test properties listed in Table I
are minimum satisfactory values for lot averages, and are applicable to the total bag.
Tensile Energy Absorption shall be in accordance with Technical Association of Pulp
and Paper Industry (TAPPI) Standard T 494.
Basis weight refers to the weight of 3,000 sq ft of single-ply or a ream of 500
sheets of 24 in. x 36 in. size paper (Ref. ASTM Standards, Part 15, April 1965).
-223-
-------
B. Bog Dimensions.
Option 1. Group A
Capacity
Face Width
Gusset Width
Option 2. Group B
Capacity
Face Width
Gusset Width
Minimum
30 gal
15 in.
11 5/8 in.
Minimum
30 gal
17 in.
10 In.
Quantity
Approximately
17,500
Quantity
Approximately
17,500
C. End closure on bags shall be either taped and sewn or closed with the use
of adhesives.
D. Two plys of paper shall be used in the bag construction; the total basis
weight of which shall meet or exceed the specified weight and test properties of
Table I. A single-ply bag will not be acceptable.
TABLE 1°
Nominal Basis
Weight (Ib)*
(24 x 36)
500 sheets
Non-Extensible Kraft Paper
Tensile
Nominal Basis
Weight (Ib)*
(24 x 36)
500 sheets
100
Minimum Basis
Weight (Ib)*
(24 x 36)
500 sheets
95.0
Dry
CD
(Ib/in. width)
34.0
Total
MDKD
(Ib/in. width)
95.0
Wet
CD
(Ib/in. width)
9.0
Extensible Kraft Paper
Tensile
Energy Absorption
Minimum Basis Dry Wet
Weight (Ib)* Tota,
(24x36) CD MD+CD CD
500 sheets (Ib/in. width) (Ib/in. width) (Ib/ln. width)
90 85.5
9.3
30.8
2.7
* Total - 2 plys.
Proposed standards for paper bags. See Appendix B, Standards for Paper and
Polyethylene Bags.
-224-
-------
IV. BAG TESTING
The City reserves the right to perform sampling, testing, and evaluation of bags
supplied for confbrmance to specifications. The lot shipment may be rejected and
returned to the bag manufacturer, freight collect, should the City determine that the
shipment does not meet specifications herein.
A, Lot Definition. For the purpose of this specification, the lot shall consist
of all paper refuse bags delivered at one time but shall not be less than 10,000 bags.
B. Sock Dimension Requirements. The sample to be used for checking for
dimensional requirements shall consist of 20 Individual bags selected randomly from
the lot from at least 10 separate bales. Lots shall be regarded as satisfactory with
regard to the absence of dimensional defects If no more than one bog in the 20 bag
sample fails to conform with dimensional requirements.
The sampling and inspection procedures for dimensions are based on an acceptable
quality level of 2.5 and an inspection level of S-2 as provided In Military Standard
105 "Sampling Procedures and Tables for Inspection by Attributes". The sample unit
is one bag.
C. Tests. Sixteen bags shall be randomly selected from the lot. Each bag
shall be from a separate bale. Two test specimens for each paper test property
specified shall be taken from each ply of each bag. The lot shall be considered
satisfactory if the averages of the tests on the sixteen bags conform with the requirements
of Table I. The tests shall be conducted in accordance with the TAPPI standard methods
listed below, except as noted above.
TAPPI Standard Method
Conditioning T 402
Tensile Breaking Strength T 404
Basis Weight T 410
Wet Tensile Breaking Strength T 456
Tensile Energy Absorption, Wet and Dry T 494
Wet tensile energy absorption is to be determined by using one-inch width
specimens that have been immersed in water for two hours at 73^F ±3.5°F.
-225-
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V. BAG CLOSURE
Indicate current firm activity, results and status in developing a suitable
closure for the paper bag. Supply samples and estimated costs, if available.
VI. PREPARATION FOR DELIVERY
Fifty (50) bags shall be packed per unit and fastened securely.
-226-
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APPENDIX C
3. BIDDER'S PROPOSAL FOR SPECIFICATION '68-30
Date
After having carefully examined the specifications for paper bags for refuse, the
undersigned (bidder) hereby proposes the following prices, to wit:
OPTION 'l
Approximately 17,500 paper bags, Group A
(according to specification '68-30) $
State additional cost for printing $_
State additional cost for colored bags, per
Inglewood selection $_
OPTION '2
Approximately 17,500 paper bags, Group B
(according to spec iff cation '68-30) $_
State additional cost for printing $_
State additional cost for colored bags, per
Inglewood selection $
COMPANY
BY
ADDRESS
PHONE
-227-
-------
APPENDIX C
4. SPECIFICATION *68-31 FOR PLASTIC BAGS FOR SOLID WASTE
I. SCOPE
This specification covers the minimum requirements for new and unused plastic
refuse bags for containment of residential refuse in the City of Inglewood, California.
II. MATERIAL REQUIREMENTS
A. Material used in manufacture shall be of the polyethylene chemical class,
thermoplastic resin.
B. Unless specified elsewhere within these specifications, provisions and
requirements of Federal Specification L-P-378b, dated February 6, 1967, as applied
to Type II - High Impact Polyethylene, shall govern the manufacture and properties
of the plastic bags.
The following polyethylene resin materials, or their equivalent, are acceptable
for bag manufacture:
DuPont Alathon 2646 Union Carbide DFD-4200
Union Carbide DPCM 143 Mobile Chemical MKC
Equivalent polyethylene resin materials may be used by the bidder. A
specification sheet describing the properties of the material should be submitted with
the bid. Minimum requirements for selected properties are tabulated in Table I.
TABLE I
Property
Impact Resistance
Tensile Strength
Machine Direction
Transverse Direction
Ultimate Elongation
Machine Direction
Transverse Direction
2.5 mil
165gm/cm2
l,700psi
l,200psi
225%
350%
Minimum Value
3.5 mil
225 gm/cm2
l,700psi
l,200psi
225%
350%
-228-
-------
Bog Testing. The City reserves the right to perform sampling, testing, and
evaluation of bags supplied for conformance to specification. The lot shipment may
be refected and returned to the bag manufacturer, freight collect, should the City
determine that the shipment does not meet the specifications herein.
III. PHYSICAL REQUIREMENTS
A. Bag Dimensions.
Group A Group B
Tube Circumference (in.) 70 54
Tube Length (in.) 44 36
Wall Thickness (in.) .0035 .0025
Quantity (approximate) 15,000 20,000
Maximum tolerance on tube circumference and length are ± 1/2 in. Tolerance
on wall thickness is ±20%.
B. Manufacture. Bags shall be extruded in a continuous tube without a
longitudinal seam. A gussetted bag may be submitted but is not required.
C. Bag bottom closures shall be watertight and have greater tensile strength
(nominal) than the wall material. Minimum 1/8 in. weld seam width will be
required.
D. Opacity. The contents of the bag should not be clearly visible. Samples
of bag material should be supplied by the bidder for City inspection of level of
opacity. There should be no color rub-off.
E. Top closures for each bag shall be provided.
F. Packaging. Bags should be securely packaged 50 to a carton.
G. Animal Repellent. Indicate on your bid the availability and cost of a
chemical additive, to be incorporated into the bag material, for repelling animal
attacks.
-229-
-------
APPENDIX C
5. BIDDER'S PROPOSAL FOR SPECIFICATION *68-31
Date
After having carefully examined the specifications for plastic bags for refuse,
the undersigned (bidder) hereby proposes the following prices, to wit:
OPTION *1
Approximately 15,000 plastic bags, Group A
(according to specification '68-31) $_
State additional cost for printing $
State additional cost for colored bags, per
Ingle wood selection $
OPTION *2
Approximately 20,000 plastic bags, Group B
(according to specification '68-31) $_
State additional cost for printing $_
State additional cost for colored bags, per
Inglewood selection $
COMPANY
BY
ADDRESS
PHONE
-230-
-------
APPENDIX C
6. SPECIFICATION *68-32 FOR HOLDERS FOR SOLID WASTE BAGS
I. SCOPE
This specification covers the requirements'for new and unused holders for refuse
bags.
II. MATERIAL REQUIREMENTS
Group A (approximately 250)
Westvaco Model H-16 Circular Holder plus Model ST-43 Pipe Stand
Hudson Tidy Sack Tubular Model TM-1
International Paper Garbax Model A
Group B (approximately 250)
St. Regis Refuse Sack Holder, Model PM-40 with Pipe Stand
Group C (approximately 50)
Mobil Model PL9-1302
Prices should be based on delivery F.O.B. the City of Inglewood corporation
yard, located at 444 N. Eucalyptus, Inglewood, California. A delivery date on or
before April 10, 1969 is required. A bid on one or more groups Is acceptable.
Firms are requested to submit bids under each of the following alternatives:
Alternate A. City purchases and retains ownership of bag holders purchased.
Alternate B. City rents the holders on a monthly basis for a period of 9 months
with the firm retaining ownership.
-231-
-------
APPENDIX C
7. BIDDER'S PROPOSAL FOR SPECIFICATION *68-32
Date
After having carefully examined the specifications for refuse bag holders, the
undersigned (bidder) hereby proposes the following prices, to wit:
OPTION 'l
Approximately 250 refuse bag holders, Group A
(according to specification '68-32) $
OPTION '2
Approximately 250 refuse bag holders, Group B
(according to specification '68-32) $_
OPTION '3
Approximately 50 refuse bag holders, Group C
(according to specification *68-32) $
COMPANY
BY
ADDRESS
PHONE
-232-
-------
APPENDIX D
LIST OF PROSPECTIVE BIDDERS
1. Plastic Bags
a. Mr. Von Froebham
Lemons Disposal
Mohawk Western Plastics, Inc.
7959 E. Imperial Highway
Downey, California 90242
b. Mr. Carl Timmons
Sales Representative
Monsanto Company
P. O. Box 3790
Anaheim, California 92803
c. Bradley's Plastic Bags
9130 Firestone Boulevard
Downey, California 90241
d. Rapco Plastics, Inc.
P. O. Box 659
612 E. McKinney
Denton, Texas 76201
e. Mr. Vern Lawson
Sales Manager
Mobil Chemical Company
Woodland, California 95695
f. Mr. E. W. Georgett
National Sales Manager
Union Carbide
Ind. Fabricated Products
One Cory Road
Morristown, New Jersey 07960
g. Mr. Sheldon Kritzer
Central Bag & Supply Company
2222 E. Olympic Boulevard
Los Angeles, California 90021
h. Mr. Ray Dickinson
Sales Representative
Bemis Company, Inc.
920 E. Pacific Coast Highway
Wilmington, California 90744
i. Mr. W. Brian Barry
Western Sales Manager
St. Regis Paper Company
6605 E. Flotilla Street
Los Angeles, California 90022
(Friedman Wide and Narrow,
Wagner bags)
{. Chase Bag Company
4900 Corona
Los Angeles, California
2. Paper Bags
a. Mr. William White
Sales Manager
Wesrvacc Building
299 Park Avenue
New York, N.Y. 10017
b. Mr. W. Brian Barry
Western Sales Manager
St. Regis Paper Company
6605 E. Flotilla Street
Los Angeles, California 90022
c. Mr. Ray Dickinson
Sales Representative
Bemis Company, Inc.
920 E. Pacific Coast Highway
Wilmington, California 90744
-233-
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d. Mr. Richard C. Martin
Western Sales Manager
International Paper Company
4635 District Boulevard
Los Angeles, California 90058
a. Mr. P. E. Strain
Product Manager
Union Camp Corp.
233 Broadway
New York, N.Y. 10007
f. Mr. Austin Byron
Manager Product Development
Hudson Paper Company
477 Madison Avenue
New York, N.Y. 10022
g. Mr. C. S. Curtiss
Manager, DTsPosit Division
Gilman Paper Company
Time & Life Building
111 W. 50th Street
New York, N.Y. 10020
h. Mr. Robert Sinclair
Marketing Manager
Crown-Zellerbach Corporation
One Bush Street
San Francisco, California 94119
-234-
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APPENDIX E
1. QUESTIONNAIRE]; PRETEST
READ EACH QUESTION CAREFULLY AND CHECK THE APPROPRIATE BOX ON THE
RIGHT.
1. Do you ever see spilled refuse in the street on your collection
day? DDDDD
2. Do you ever see files or ants in your trash cans? DDDDD
3. Do you ever find it difficult or inconvenient to carry emptied
trash cans from the curb to your storage area? DDDDD
4. Does the collector ever leave small amounts of refuse in trash
cans? DDDDD
5. How often are your trash cans damaged by the collector? . . . . DDDDD
6. Do you ever smell unpleasant odors in your trash cans? DDDDD
7. How often do you feel the appearance of your neighborhood is
less attractive when trash cans are at the curb on collection
day? D D D D D
PLEASE GIVE US YOUR COMMENTS ON THE CITY OF INGLEWOOD REFUSE
COLLECTION SYSTEM.
-235-
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APPENDIX E
2. QUESTIONNAIRE 2: SOLID WASTE BAG USE
1. Please check the system you have been using for the past three months:
St. Regis Paper Bag and Holder D
Mobil Plastic Bag and Holder D
International Garbax Paper Bag and Holder G
Plastic Liner Bags D
St. Regis Paper Bag (no holder) D
2. Do you live in: G A private residence G An apartment house
3. If the system you used included a bag holder, please answer the following
questions:
a) Did you have trouble mounting the bag on the holder? G Yes G No
b) Did you have difficulty placing refuse in the bag? G Yes D No
c) Do you consider the holder and bag more attractive in
appearance than the conventional refuse container? G Yes G No
d) Did you have trouble with the holder tipping over? D Yes D No
e) Did the holder lid function satisfactorily? D Yes D No
4. If the system you used did not include a bag holder, please answer the following
questions:
a) Did you have problems placing the liners into the cans? G Yes G No
b) Did you have difficulty placing refuse into the bag? G Yes G No
5. Did you find it necessary to continue using conventional containers along with
the bag system? G Yes G No If yes, please indicate briefly your
reasons:
6. Did you find tfie bags failed: G Never G Occasionally G Frequently
-236-
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7. What was the primary cause of these failures?
Sharp objects Q
Wet refuse Q
Heavy refuse Q
Animal damage Q
Rough handling Q
Other (please describe) Q
8. DTd you notice any Improvement in:
Noise factor D Yes D No
Odor conditions D Yes D No
Fly problems QYes D No
Spillage D Yes D No
Neighborhood appearance D Yes Q No
9. Did you have problems closing the bag following use? Q Yes Q No
10. Was it difficult to carry the bags to the curb on collection day? D Yes D No
11. All things considered, did you like the system? G Yes D No
12. What did you particularly like about the system?
13. What did you particularly dislike about the system?
Please return the completed questionnaire to us in the enclosed envelope. Thank you
for your cooperation.
-237-
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APPENDIX E
3. QUESTIONNAIRE 3: SOLID WASTE BAG SYSTEM COMPARISONS
1. Check the refuse bag system used
since the end of July 1969.
St. Regis Paper Bag & Holder Q
Mobil Plastic Bag & Holder D
International Garbax Paper Bag
& Holder D
Plastic Uner Bags for Cans D
2. Was this the same system used during
the 3 month period prior to the end of
July 1969?
Yes D (90 to Question 6)
No D (go to Question 3)
3. Check the system used during the 3
month period prior to the end of
July 1969.
St. Regis Paper Bag & Holder D
Mobil Plastic Bag & Holder D
International Garbax Paper Bag
& Holder D
Plastic Liner Bags for Cans Q
4. In comparison with the bag system used
prior to the end of July 1969, rate the
system you are now using as better,
about the same, or worse for:
About
the
Better Same Worse
General appearance t] tf O
Closing the HI led
bag ana
Mounting bag on
holder DDD
About
the
Better Same Worse
Placing refuse in
bag
Tipping of the
holder
Holder lid
operation
Frequency of bag
failure
Odor conditions
Fly problems
Animal attack
Spillage
Carrying bag to
curb
Storage of bog
supplies
5. In view of the items listed in Question
4, is the bag system in current use
preferred over the one in use prior to
the end of July?
D
D
D
D
D
D
D
n
D
D
D
D
D
D
D
n
D
n
n
n
n
n
n
n
n
n
n
n
n
n
Yes
No
6. The following questions apply to the
bag system you are now using .
7. Do you live in: Private residence
Apartment house
8. Did you find that the bags failed:
Never
Occasionally
Frequently
Q
-238-
-------
9. What was the primary cause of these
failures?
Sharp objects D
Wet refuse Q
Heavy refuse Q
Animal damage Q
Rough handling D
10. Did you notice any improvement in:
16.
Collection noise
Odor conditions
Fly problems
Spillage
Neighborhood
appearance
Yes D No D
Yes D No D
Yes D No D
Yes D No D
Yes D No D
11. Did you hove problems closing the bag
following use? Yes Q No D
12. Was it difficult to carry the bags to
the curb? Yes D No Q 17.
13. All things considered, did you like
tfie system? Yes D No D
14. If there was anything you particularly
liked about the system, please
comment:
18.
If the bag system you are now using
includes a special bag holder stand,
please answer the following:
a) Did you have trouble mounting the
bag on the holder? Yes Q No Q
b) Did you have difficulty placing
refuse In the bag? Yes Q No D
c) Do you consider the holder and bag
more attractive in appearance than
the conventional refuse container?
Yes D No D
d) Do you have trouble with the
holder tipping over?
Yes D No D
e) Does the1 holder lid function
satisfactorily? Yes D No Q
If the system you used did not include
a bag holder, please answer the
following:
a) Did you have difficulty placing
refuse into the bag?
Yes D No D
Please indicate any special comments
you have regarding the test.
15. If there was anything you particularly
disliked about the system, please
comment:
Please return the completed questionnaire as soon as possible in the enclosed envelope.
-239-
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APPENDIX E
4. QUESTIONNAIRE 4; BRIARWOOD CONDOMINIUM - SOUP WASTE BAG USE
Dear Citizen of Brfarwood:
For the past six months you have been involved in making a study of a row method of
refuse collection and storage system with the City of Inglewood which has been
sponsored by the United States Public Health Service.
To help us evaluate this system, we would appreciate it if you would take a few
moments to answer the following questions.
1. Did you have trouble mounting bag? Yes Q No G
2. Did you have difficulty placing refuse in the bag? Yes Q No Q
3. Do you consider the holder and bag more attractive than
the conventional refuse container? Yes Q No D
4. Did you have trouble with the holder tipping over? Yes Q No D
5.. Did the holder lid function satisfactorily? Yes Q No G
6. Did the bags fail often? Yes D No Q
7. What was the primary cause of the failures?
Sharp objects _________ Animal damage __________
Wet refuse Rough handling
Heavy refuse __________
8. Did you notice any improvement in:
Noise factor Yes G No D Fly problem Yes D No Q
Odor conditions Yes D No D Spillage Yes Q No D
Neighborhood appearance Yes Q No Q
9. Did you have problems closing the bag? Yes D No G
10. Was there a problem in storage of bags before use? Yes Q No G
11. All things considered, did you like the system? Yes G No G
-240-
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12. Please make any comment* about the system that will give us your opinion of the
system.
-241-
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APPENDIX E
5. QUESTIONNAIRE 5: BAG SYSTEM EVALUATION
1. Please check different systems used by
you during the past 1-1/2 years.
St. Regis Paper Bag & Holder Q
International Paper Bag & Holder D
Mobil Plastic Bag & Holder D
Mobil Plastic Liners for Barrels D
Plastic Bags with Drawstrings Q
2. Of the different types of bags that you
used, which did you like best?
3. Did you notice any improvement in:
Noise Factor Yes Q No
Neighborhood
Appearance Yes D No
Spillage on Parkway
or Street Yes D No
4. Did you have trouble installing liner
into barrel? Yes Q No
5. Did you have trouble removing liner
from barrel? Yes D No
Item
Frequency of bag failure
Ease of closing filled bag
Ease of mounting bag on holder
Ease of filling bag
Ease of operation of holder lid
Odor conditions
Ease of storage of bag supply
Ease of carrying filled bag
Frequency of spillage
Frequency and extent of
animal damage
Importance
None
Very little
Moderate
Great
All things considered, did you like the system? Yes D No D
Please make any comments about the system that might help us to make an evaluation.
Please return to Harry Frisby, Sanitation Superintendent, City of Inglewood. An
envelope has been enclosed for your convenience.
-242-
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APPENDIX E
6. LANDFILL OPERATOR QUESTIONNAIRE
Compared to normal residential refuse, how would you evaluate working bagged refuse
in the following operations:
Better Same Worse
123 4567 8910
a. Pushing D D D
b. Spreading D D D
c. Compacting ODD _.
How would you rate bagged refuse compared to normal residential refuse for the
following:
Better Same Worse
123 4567 8910
a. Blowing refuse D D D
b. Odors D D D
c. Dust produced
In working ODD
Comments:
-243-
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APPENDIX E
7. NATIONWIDE SOLID WASTE BAG USE QUESTIONNAIRE
1. City State Population
2. Do City regulations permit use of plastic and/or paper bags as refuse containers?
Yes; _______ No. Please provide a copy of City Regulations.
3. Please estimate current (1970) percentage of households using plastic and/or paper
bags as refuse containers. 0-5%; 6-20%; 2MO%; 41-60%;
61-80%; 81-95%; 96-100%.
4. Of total number of refuse bags used in City as refuse containers, about % are
plastic and % are paper.
5. Does City plan to use, or permit householders to use, disposable bags for refuse
containers in the future? Yes; No. If Yes, will bags be plastic
only; or both?
6. If now used, how do householders obtain disposable bags? (Please describe)
^ •
7. What size bag is now provided? gallons.
8. Householders pay about <: per paper bag; c per plastic bag.
9. Does City now incur costs of bag distribution to residents? Yes; No.
If Yes, what is method of distribution and approximate cost per bag distributed?
10. Please rate, in your opinion, the householder's reaction to the use of disposable bags
in your City. Circle one number from 1 to 10.
1 2 3
very unsatisfactory
4567
satisfactory
8 9 10
very satisfactory
11. Please indicate what problems, if any, the City has experienced in the collection
and/or final disposal of refuse bags, and whether the difficulty involved paper or
plastic bags.
12. If plastic bags are now used or planned for future use, do you personally favor their
use as a liner; with a holder; and what minimum thickness? mil.
13. In your personal judgment, which type of bag is superior? plastic; paper.
-244-
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14. Do you know of any private scavenger firms or other cities who supply plastic and/or
paper bags to their customers? Yes; _____ No. If yes, please write their
names and addresses on back of this questionnaire.
15. Has City conducted studies to determine refuse collection cost savings resulting from
use of plastic and/or paper bags? Yes; _____ No. If Yes, please send copy
of study results.
16. OPTIONAL: Your name and title
PLEASE USE REVERSE SIDE FOR ADDITIONAL COMMENTS
-245-
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APPENDIX E
.8. BIN LINER QUESTIONNAIRE
Name of Business
1. Did you notice any improvement in:
a. Fly Problems Yes Q No D
b. Odors Yes D No Q
c. Bin Cleanliness Yes D No D
2. Did you have trouble installing the liner
into the bin? Yes Q No D
If Yes, pleasa explain:
3. Do you clean your bin regularly? Yes Q No Q
4. Has the use of liners reduced the frequency
of need for cleaning of bin? Yes Q No D
5. All things considered, did you like the system? Yes G No D
6. Do you feel the City of Inglewood should
encourage the use of bin liners for business
locations that have food waste? Yes D No Q
Comments:
We wish to thank you for your cooperation in this study and if you have any questions,
please call Harry M. Frisby, Sanitation Superintendent, 674-7111, Ext. 361, City of
Inglewood.
-246-
-------
APPENDIX F
LABORATORY PROCEDURE
FOR ANALYSIS OF MICROBIOLOGICAL DUST TESTS
Bacterial sample plates 100 mm in diameter containing brain heart infusion ogar
were exposed for 10 seconds during collection of domestic solid waste. The exposed
agar plates were incubated at room temperature (75 ±4°F) for several days. Microbial
colonies developing on these plates during incubation were counted at 24-hour
intervals. A distinction was made between bacteria and fungi on the basis of their
colonial morphology.
After 48 hours of incubation, the most abundant types of colonies of bacteria
were selected and streaked on blood agar plates. The plates were incubated at room
temperature and examined after 24 hours for bacterial growth and hemolysis of red
blood cells around the growing colonies. All the bacteria grown on blood agar plates
were stained for gram's stain and viewed under a microscope at a magnification of
970 X.
On the basis of colonial morphology, the reaction to gram's stain, and cellular
morphology, the generic bacteria were tentatively identified.
Predominant fungi colonies were identified on the basis of their fruiting structures.
For this purpose a portion of the colony was mounted on a microscopic slide and teased
onto a drop of lactophenol cotton blue fluid, covered with a cover-glass, and pressed
gently. The slide was then examined under a microscope (500 X magnification). When
necessary, fungi were subcultured on Sabourand's dextrose agar and treated as above
for proper identification.
-247-
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APPENDIX G
BIBLIOGRAPHY ON DUST STUDIES
Albrink, W. S. Pathogenesis of inhalation anthrax. Bacteriological Reviews,
25(3):268-273, Sept. 1961.
Bailey, W. R., and E. G. Scott. Diagnostic microbiology. 2d ed. St. Louis,
C. V. Mosby Company, 1966.
Conant, N. F., D. T. Smith, R. D. Baker, J. L. Callaway, and D. S. Martin.
Manual of clinical mycology. Philadelphia, W. B. Saunders Company, 1963.
Dubos, R. J., and J. G. Hirsch, eds. Bacterial and mycotic infections of man.
4th ed. Philadelphia, J. B. Lippincott Company, 1965.
Fothergill, L. D. Microbial aerosols and respiratory infections. [Summary
of symposium held at 57th General Meeting of the Society of American Bac-
teriologists, Detroit, Mich., Apr. 29, 1957.] Bacteriological Reviews,
21(4):249-250, Dec. 1957.
Neter, E. Enterobacteriaceae of medical significance. [Summary of symposium
held at 56th General Meeting of the Society of American Bacteriologists,
Houston, Texas, May 1, 1956.] Bacteriological Reviews, 20(4):272-273, Dec.
1956.
[Proceedings of] Conference on airborne infections. Bacteriological Reviews,
25(3):173-382, Sept. 1961.
Smith, H. The use of bacteria grown in vivo for studies on the basis of their
pathogenicity. Annual Review of Microbiology, 12:77-102. 1958.
White, D. C. Respiratory systems in the hemin-requiring Haemophilus species.
Journal of Bacteriology, 85(1):85-96, Jan. 1963.
Wilson, J. W., and 0. K. Plunkett. The fungus disease of man. Los Angeles,
University of California Press, 1967.
Youmans, G. P. The pathogenic "atypical" mycobacteria. Annual Review of
Microbiology. 17:473-494, 1963.
-248-
-------
APPENDIX H
RESPONSE SUMMARY: QUESTIONNAIRES 2 AND 3
The following tables list the detailed responses to each questionnaire. Table HI
and H3 are expressed In number of responses, and Tables H2 and H4 are given In
percentage of responses.
-249-
-------
TABLE HI
SUMMARY OF RESPONSES TO QUESTIONNAIRE 2
Mobil0
& Holder
(114) *
Yes No
St. Regisb
& Holder
054)
Yes No
International'
& Holderv
014)
Ye* Np
' Friedman Wide
Can Linerc
021)
Yes No
St. Regis"
No Holder
(337
Yes No
Total
(536)
Y* No
linpi oveipents
Holder end bag more attractive
than conventional solid
waste container
Neighborhood appearance
Collection Noise
Odor Conditions
Fly problem
Spillage problem
Difficulties
Mounting bag or liner
Placing solid waste in bag
Closing bag
Carrying bags to curb
Necessary to continue to use
cans with bags
Did holder lid function
satisfactorily
Tipping over of holder
88
87
76
66
55
67
36
45
30
4
57
56
7
23
13
26
33
38
33
79
69
76
97
24
58
105
131
123
102
100
101
97
21
17
38
14
46
145
7
21
19
33
35
36
40
133
136
103
129
65
5
142
87
87
70
63
66
57
6
15
26
12
42
103
8
18
12
20
37
33
36
105
87
78
90
38
7
104
N.A.C
103
78
80
72
90
8
8
25
20
47
N.A.
N.A.
N.A.
9
25
25
31
16
108
108
79
94
67
N.A.
N.A.
N.A.
27
21
16
17
15
5
8
12
4
13
N.A.
N.A.
N.A.
3
5
8
9
11
16
21
20
27
15
N.A.
N.A.
306
427
347
325
311
326
75
93
131
54
205
70
22
62
56
109
138
147
136
441
421
356
437
209
304
351
Continued . . .
-------
TABLE HI (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 2
never
Bogs failed occasionally
frequently
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
Mobil0
& Holder
014)*
Yes No
30
57
16
64
7
27
20
4
70 24
St. Regis'*
& Holder
(154)'
Yes No
79
53
8
19
19
6
33
1
118 22
lnternotionqlb Friedman Wide
& Holder
OWjr
Y« No
55
44
9
26
29
12
21
0
82 16
Can Liner
021)
Y« No
61
53
3
52
5
17
10
4
106 7
St. Regis^
No Holder
(33)
Y« No
15
15
3
9
7
6
7
1
26 4
Total
(536)
Yes No
240
222
39
172
67
68
91
10
402 73
, Mdbll Keepaway (2.5 mil) polyethylene bag.
Paper bag.
d Polyethylene (3.0 mil).
Figures in parentheses give number of
Not applicable.
questionnaires
returned.
-------
TABLE H2
•I
SUMMARY OF RESPONSES TO QUESTIONNAIRE 2 (Expressed in Percentages)
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bags or liner
Placing solid waste in bag
Closing bag
Carrying bags to curb
Necessary to continue to use cans
with bags
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure6
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
Mobil0 & Holder
Yes No N.R.d
77.2
76.3
66.7
57.9
48.2
58.8
30.7
39.5
26.3
3.5
50.0
49.1
6.1
61.4
20.2
11.4
22.8
28.9
33.3
28.9
69.3
60.5
66.7
85.1
21.1
50.9
92.1
26.3
50.0
14.0
52.5
5.7
22.1
16.4
3.3
21.1
2.6
12.3
10.5
13.2
18.5
12.3
0
0
7.0
11.4
28.9
0
1.8
17.5
St. Regis6 & Holder
Yes No N.R.
85.1
80.0
66.2
64.9
65.6
63.0
13.6
11.0
24.7
9.1
29.9
94.2
4.5
76.6
13.6
12.3
21.4
22.7
23.4
26.0
86.4
88.3
66.9
83.8
42.2
3.2
92.2
51.3
34.4
5.2
24.4
24.4
7.7
42.3
1.2
14.3
1.3
7.7
12.4
12.4
11.0
11.0
0
0.7
8.4
7.1
27.9
2.6
3.3
9.1
International &
Yes No
76.3
76.3
61.4
55.3
57.9
50.0
5.3
13.2
22.8
10.5
36.8
90.4
7.0
71.9
15.8
10.5
17.5
32.5
28.9
31.6
92.1
76.3
68.4
78.9
33.3
6.1
91.2
48.2
38.6
7.9
20.5
33.0
13.6
23.9
14.0
Holder
N.R.
7.9
13.2
21.1
12.2
13.2
18.4
2.6
10.5
8.8
10.6
29.9
3.5
1.8
14.1
Continued . . .
-------
TABLE H2 (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 2 (Expressed in Percentages)
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bags or liner
Placing solid waste in bag
Closing bag
Carrying bags to curb
Necessary to continue to use cans
with bags
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure6
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
Friedman Widec Can Liner
Yes No N.R.
t
N.A.f
85.1
64.5
66.1
59.5
74.4
6.6
6.6
20.7
10.5
38.8
N.A.
N.A.
87.6
N.A.
7.4
20.7
20.7
25.6
13.2
89.3
89.3
65.3
77.7
55.4
N.A.
N.A.
50.4
43.8
2.5
59.1
5.7
19.3
11.4
4.5
5.8
N.A.
7.5
14.8
13.2
14.9
12.4
4.1
4.1
14.0
5.8
5.8
N.A.
N.A.
6.6
St. Regis, b No
Yes No
N.A.
81.8
63.6
48.5
51.5
45.5
15.2
24.2
36.4
12.1
39.3
N.A.
N.A.
78.8
N.A.
9.1
15.2
24.2
27.3
33.3
48.5
63.6
60.6
81.8
45.4
N.A.
N.A.
45.5
45.5
9.1
30.0
23.3
20.0
23.3
3.4
12.1
Holder
N.R.
N.A.
9.1
21.2
27.3
21.2
21.2
39.3
12.2
3.0
6.1
15.2
N.A.
N.A.
9.1
Yes
80.1
79.7
64.7
60.6
59.0
60.8
14.0
17.4
24.4
10.1
38.2
18.3
5.8
75.0
Total
No
16.2
10.4
20.3
25.7
27.4
25.4
82.3
78.5
66.4
81.5
39.0
79.6
91.9
44.8
41.4
7.3
12.2
16.4
16.7
22.3
2.5
13.6
N.R.
3.7
8.7
15.0
13.7
14.6
13.8
3.7
4.1
9.2
8.4
22.8
2.1
2.3
11.4
Continued . .
-------
TABLE H2 (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 2
(Expressed fn Percentages)
k Mobil Keepaway (2.5 mil) polyethylene bag.
Paper bag.
d Polyethylene 0.0 ml I).
No response.
, Percentages are based upon total number of failure types reported.
Not applicable.
-254-
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TABLE H3
SUMMARY OF RESPONSES TO QUESTIONNAIRE 3
Mobil0
& Holder
(98)<*
Yes No
St. Regisb
& Holder
(102)
Yes No
International^
& Holder
(86)
Yes No
Wagner
Can LJnerc
(124)
Yes No
St. Reaisb
No Holder
0)
Yes No
Total
(413)
Yes No
Improvements
Holder and bag more attractive
than conventional solid
waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bag
Placing solid waste in bag
Closing bag
Carrying bags to curb
Did holder lid function
satisfactorily
Holder tipping over
70
75
67
54
53
57
41
52
41
6
36
25
23
19
22
31
36
28
52
42
58
90
55
67
•
80
90
85
68
66
69
21
11
27
9
86
12
15
10
11
23
24
20
77
87
75
92
12
86
64
67
60
52
49
54
16
18
34
14
71
9
15
18
23
25
31
23
65
63
50
72
9
72
N.A.e
103
90
75
73
83
N.A.
14
32
23
N.A.
N.A.
N.A.
16
28
37
41
30
N.A.
72
90
96
N.A.
N.A.
N.A.
2
2
1
1
1
N.A.
0
1
1
N.A.
N.A.
N.A.
0
0
1
1
1
N.A.
0
1
2
N.A.
N.A.
214
337
304
260
242
264
78
95
135
53
193
46
53
63
84
117
133
102
194
264
274
352
76
225
Continued . . .
-------
TABLE H3 (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 3
never
Bogs failed occasionally
frequently
Primary causes of failure
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
° Mobil Keepoway (2.5
Paper bag .
* Polyethylene (3. 5 mil)
Figures in parentheses
Not applicable.
Mobil0 St. Regisb
& Holder & Holder
(98)d 002)
Yes No Yes No
25 48
53 48
16 6
58 33
6 23
18 5
26 26
5 0
67 29 92 10
mil) polyethylene bag.
•
give number of questionnaires
International
& Holder
(86)
Yes No
40
29
5
22
19
3
25
2
69 15
returned.
Wagner
Can Linerc
024)
Yes No
58
59
6
59
3
10
20
7
106 13
St. Regis*3
No Holder
(?)
Yes No
1
3
0
0
1
0
0
1
2 1
Total
(413)
Yes No
172
192
33
172
52
36
97
15
336 68
-------
N3
TABLE H4
SUMMARY OF RESPONSES TO QUESTIONNAIRE 3 (Expressed in Percentages)
Mobil0 & Holder
Yes No N.R.d
Improvements
Holder and bag more attractive than
conventional solid waste container
Neighborhood appearance
Collection noise
Odor conditions
Fly problem
Spillage problem
Difficulties
Mounting bag
Placing solid waste in bag
Closing bag
Carrying bags to curb
Did holder lid function satisfactorily
Tipping over of holder
never
Bags failed occasionally
frequently
Primary causes of failure6
Sharp objects
Wet solid waste
Heavy solid waste
Animal damage
Rough handling
Did you like the system
71.4
76.5
68.4
55.1
54.1
58.2
41.8
53.1
41.8
6.1
35.3
25.5
68.4
23.5
19.4
22.4
31.6
36.7
28.6
53.1
42.9
59.2
91.8
53.9
68.4
25.5
54.1
16.3
51.3
5.3
15.9
25.1
4.4
29.6
5.1
4.1.
9.2
13.3
9.2
13.2
5.1
4.0
0
2.1
10.8
6.1
2.0
St. Regis5 & Holder
Yv No N.R.
78.4
88.2
83.3
66.7
64.7
67.6
20.6
10.8
26.5
8.8
87.8
11.8
90.2
14.7
9.8
10.8
22.5
23.5
19.6
75.5
85.3
73.5
90.2
12.2
84.3
47.1
47.1
5.9
37.9
26.5
5.7
29.9
9.8
6.9
2.0
5.9
10.8
11.8
12.8
3.9
3.9
0
1.0
0
3.9
0
International0 &
Yes No
74.4
77.9
69.8
60.5
57.0
67.8
18.6
20.9
39.5
16.3
82.6
10.5
80.2
17.4
20.9
26.7
29.1
36.0
26.7
75.6
73.3
58.1
83.7
10.5
83.7
46.5
33.7
5.8
31.0
26.8
4.2
35.2
2.8
17.4
Holder
N.R.
8.1
1.2
3.5
10.4
7.0
10.5
5.8
5.8
2.4
0
6.9
5.8
2.4
Continued .
-------
-------
TABLE H4 (Continued)
SUMMARY OF RESPONSES TO QUESTIONNAIRE 3
(Expressed In Percentages)
, Mobil Keepoway (2.5 mil) polyethylene bag.
Paper bag.
|j Polyethylene (3.5 mil).
No response.
f Percentages are based upon total number of failure types reported.
Not applicable.
-259-
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APPENDIX I
Mathematical Model Description
A. Model Inputs
1. General; A simplified model was used to simulate the time required For the
collection of refuse. The purpose of the model was to enable projections of
refuse collection system performance for alternative crew sizes, collection
methodologies, truck sizes, haul distances, and labor and equipment costs.
The following factors which affect the efficiency of collection were included
in the model:
a. Mean quantity of refuse per collection stop.
b. Driving time between the route and the disposal site.
c. Mean collection time at each collection stop and travel time
to the next stop.
d. Total non-productive time including: travel time between the
yard and the route and between the disposal site and the yard;
relief, lunch, and dispatch time; and inc identic I time losses
resulting from road conditions, equipment breakdown, etc.
e. Mean disposal time per load at the disposal site.
2. Assumptions and Data; The basic model assumptions and data inputs were as follows:
a. Collection plus travel time per stop in minutes from Table 66:
CS=1 CS=2 CS=3
Bag routes: t= 0.58 0.53 0.41
Canroutes:t= 0.74 0.69 0.58
Collection times for two-and three-man crews collecting bags was derived from Methods-
Time-Measurements (MTM) analyses as described in the One Man Report as follows:
Adjusted MTM values from the One-Man Report Rgures 40 to 42 page 96-98,
correlated well with field data. The MTM unadjusted value for 3 cans on
Figure 29 (p. 68) was plotted on Figures 40 to 42. The percentage increases
in the latter values, calculated to obtain the field values for 3 cans as shown on
Figures 40 to 42,were:
CS = 1 : 0.5 to 0.62 min.; 25%
CS = 2 : 0.33 to 0.55; 66%
CS =3 : 0.29 to 0.45; 55%
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Applying these percentages to the unadjusted MTM times for disposable items given in
Figure 30 (p. 69),the times for 2- and 3-man crews were obtahed;adding a constant travel
time between stops of 0.13 minutes the times were calculated as follows:
CS = 2: t = 0.13 + 0.24 + (.66) (.24) = 0.40 + 0.13 = 0.53 min.
CS=3:t= 0.13 + 0.18 + U55) (.18) = 0.28 + 0.13 = 0.41 min.
Collection times for 2- and 3-man crews on can routes were derived as follows:
The 0.74 min for 1-man can collection plus travel to the next stop when reduced
by the 0.13 min travel time (0.61 min) is identical to the 0.62 min given on page 21
of the One-Man Report; Times for 2- and 3-man crews were considered similar
also, and when travel time between stops was added the 2- and 3-man crew times
for can collection were derived.
CS=2: 0.558+ 0.13 = 0.69 min.
CS=3: 0.454+ 0.13 = 0.58 min.
b. Minimum partial loads to be collected were set at: 1/8, 1/4 and 1/2.
c. Standard work day of 8 hours (480 min day), with a maximum allowable overtime of
30 min (510 min/flay).
d. Crew members are paid for a minimum of 8 hours per day at $4.80 per hour; if they
finish early they are relieved.
e. Time worked beyond 8 hours is overtime at 1.5 times the normal rate.
f. Collection truck sizes and costs used in the model were:
truck volume, cu yd: 20, 25, 32, 35, 40
truck costs (Table 67), $/min: 0.073, 0.078, 0.085, 0.093, 0.095.
g. Refuse quantities per stop: Q = 50, 60, 70 Ib.
h. Non-productive time; K = 100, 75, 50 min.
i. One-way drive time, route to disposal B= 50, 30, 10.
j. Mean density of waste in the collection vehicle after compaction: 550 Ib per cu yd.
-261-
-------
3. Symbols
B One way average driving time between the route and the dis
posal site (min)
D The mean disposal time (min/load)
d Mean density of waste in the vehicle (Ib/cu yd)
K The total non-productive time (min)
PL Partial load (fraction)
SPL Number of services for a full or partial load
TPL Time to collect one vehicle load (min)
X Total time to complete a days work (min)
V Vehicle volumetric capacity
t Time necessary for one service (min)
B. Model Calculations
The model calculations are made as follows:
I . Calculate the number of services for a full load (SPL):
Q
2. The time to collect one load (TPL):
TPL = SPL* t
The total time to complete one trip is found from:
3. X(I) = TPL+K + B + D
4. If X (I) < 510 min check to see if X (I) > 480 min.
5. If X (I) > 480 min, only one trip is made for the day. Complete Step 16.
6. If X (I) >5IO min, a partial load is collected for the day:
PL=(5IO-X (I) + TPL) /TPL
7. set X (I) = 5 10 min where load = PL
8. If X (I) < 480 min, the next trip (travel time) XX is calculated without
collection by:
9. XX = X (I)+2*B + D
-262-
-------
10. If XX £ 510 min the trips are finished for the day. Go to step 16.
II. If XX < 510 min. the partial load that can be collected in the remaining
rime is calculated.
PL=(5IO-XX)/TPL
A minimum allowable load may be specified, such as 1/8, 1/4, 1/2.
12. If PL < PL min, then no more trips are made. Go to step 16.
13. If PL£ PL min, then make another trip and calculate the load from Step 6.
14. If PL < 1.0, set X = 510 min and collect a partial load. Go to step 16.
15. If PL = 1.0, calculate the number of trips for the day until the time con-
straints are satisfied: X = XX + TPL and repeat from step 5.
16. When the trips for a day are finished and totalled, then the following are
calculated:
(I) load size tons; (2) number of services; (3) man minutes per ton for the
crew size; (4) manpower costs at straight time and overtime if used; (5)
labor cost per ton; (6) vehicle cost per ton; (7) total cost per ton; and
(8) cost per service.
C. Model Simulations and Behavior
Several model simulation runs were made under varying collection system conditions of
partial loads, quantity of waste per stop, collection truck volumes, non-productive
time, and one way drive time from route to disposal.
The basic equation of the model given on page 55 is linear; the behavior of the model
when simulations are run under varying system conditions, however, is nonlinear. The
nature of the constraints on daily work time and their interaction with different vehicle
capacities and crew sizes results in nonlinear solution lines (see Figures 50-60 in text)
when variables are plotted as a function of truck volume. This occurs because the daily
work time constraint causes the solution to behave as a modified step - function. The
actual time a given vehicle/crew spends on the route and in transit is used to determine
collection costs; the amount of time a vehicle/crew spends on a route may, therefore,
vary from 510 minutes to less'than 480 minutes. Collection costs include overhead for
differences in work times, numbers of services and trips per day. The non-productive
time per day is assumed constant and is added only once in the model solution regard-
less of the number of trips completed during the day.
-263-
-------
REFERENCES
1. Private communication from Mr. E. H. Taylor, Executive Director, National
Refuse Sack Council, Sept. 28, 1968.
2. A study of solid waste collection systems comparing one-man with multi-
man crews; final report. Ralph Stone and Company, Inc., Engineers.
Public Health Service Publication No. 1852. Washington, U. S. Govern-
ment Printing Office, 1969. 175 p.
3. Private communication, London, England, July 24, 1970.
4. Private communication, BF Chemicals (U.R.) Limited, London, England.
5. American Public Works Association Research Foundation. Paper bags for
household refuse handling. Special Report No. 26. Chicago, American
Public Works Association, 1963.
6. Plastic bags get wider use in Toronto. Refuse Reaoval Journal, 9(10):
6, 48, Oct. 1966.
7. Private communication and report, Montreal, Canada.
8. Plastic can liners speed city garbage pick-up. American Paper Merchant,
Nov. 1968. p. 24-25. [Published by Peacock Business Press, Park Ridge,
Illinois.]
9. Bowker, A. H., and S. J. Lieberman. Engineering statistics. Englewood
Cliffs, New Jersey, Prentice-Hall, 1959.
10. Linsdale, D. D., and K. E. White. A survey of fly production in house-
hold refuse containers with and without plastic liners in the City of
Inglewood, California. Berkeley, State of California, Department of
Public Health, Bureau of Vector Control and Solid Waste Management,
May 1970.
11. Star, S. Safety for refuse collection systems. In Proceedings; Fifth
Annual Seminar and Equipment Show, San Francisco, California, Nov. 9-11,
1967. Governmental Refuse Collection and Disposal Association, p. 33-41.
yo494
-264-
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THE FOLLOWING PAGES ARE DUPLICATES OF
ILLUSTRATIONS APPEARING ELSEWHERE IN THIS
REPORT. THEY HAVE BEEN REPRODUCED BY
A DIFFERENT METHOD SO AS TO .FURNISH THE
BEST POSSIBLE DETAIL TO THE USER.
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