PB-239 775
ANALYSIS OF SOURCE SEPARATE COLLECTION OF RECYCLABLE
SOLID WASTE-SEPARATE COLLECTION STUDIES
SCS ENGINEERS, INCORPORATED
PREPARED FOR
ENVIRONMENTAL PROTECTION AGENCY
1974
DISTRIBUTED BY:
KTLT
National Technical Information Service
U. S. DEPARTMENT OF COMMERCE
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BIBLIOGRAPHIC DATA
SHEET
1. Report No.
PB 239 775
4. Title and Subtitle
Analysis of Source Separate Collection/of Recyclable Solid
Waste-Separate Collection Studies
5. Report Date
1974
6.
7. Author(s)
SCS Engineers, Inc.
8. Performing Organization Kept.
No.
9. Performing Organization Name and Address'
SCS Engineers, Inc.
40l4 Ong Beach Boulevard
Long Beach, California 90807
10. Project/Task/Work Unit No.
11. Contract/Grant No.
EPA 68-01-0789
12. Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
Offcie of Solid Waste Management Programs
Washington, D.C. 20460
13. Type of Report & Period
Covered
Final
14.
15. Supplementary Notes
16. Abstracts
This report summarizes a study that .assesses the technical and economic
feasibility of separately collecting recyclable materials from the home. Twenty-two
communities practicing separate collection were studied and detailed case studies
of each system were summarized. A computer model ufc-ili«lng this data was formulated
and sample cost projections using various operating parameters are presented. In
addition* a study of twenty households was performed to quantify the time, cost,
and storage impact on participating families. This report should be helpful to
city governments interested in instituting separate collection programs for the
recovery of recyclables from the waste stream.
17. Key Words and Document Analysis. 1/a. Descriptors
I7b, Identifiers/Open-Ended Terms
Source Separation
Separate Collection
lecycling systems
Materials Recovery
17e. COSATI Field/Group
18. Availability Statement
19..Security Class (This |21. No. of Pages
Report) "
20. Security Class (Thu
UNCLASSIFIED
FORM NTI»-SS (REV. 10-73) ENDORSED BY ANSI AND UNESCO.
THIS FORM MAY BE REPRODUCED
USCOMM-DC
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ANALYSIS OF SOURCE SEPARATE COLLECTION
OF RECYCLABLE SOLID WASTE-
SEPARATE COLLECTION STUDIES
Final Report
This report (SW-95c.3) on work performed under
Federal solid waste management contract no. 68-01-0789
is reproduced as received from the contractor.
Volumes I and II were written by SCS Engineers* Inc.
U.S. Environmental Protection Agency
1975
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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.
An environmental protection publication CSW-95c.l) in the solid waste
management series.
ii
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CONTENTS
Section Page
I SUMMARY AND CONCLUSIONS 1
Household Separation 1
Household Collection Considerations 1
Separate Truck Approach 1
Rack Approach 2
II INTRODUCTION 5
III HOUSEHOLD SEPARATION OF RECYCLABLE
MATERIALS 7
Material Generation 9
Material Preparation 10
Material Storage 13
IV SEPARATE COLLECTION CONSIDERATIONS 17
Program Initiation 17
Socio-Economic Considerations 20
Public Response 23
Public Relations 24
Scavenger Problems 27
Material Preparation Requirements 28
V SEPARATE COLLECTION: SEPARATE TRUCK
APPROACH 31
Separate Truck Activities 33
Startup Costs 33
Equipment and Manpower Utilization 36
Separate Truck Program Performance 41
Separate Truck Program Economics 51
Model Economics for the Separate
Truck Approach 64
VI SEPARATE COLLECTION: RACK APPROACH 77
Rack Activities 80
Startup Costs 82
Equipment and Manpower Utilization 84
Rack Program Performance 84
Program Economics 87
Model Economics for the Rack Approach 93
111
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CONTENTS
Section
VII ACKNOWLEDGEMENTS
VIII REFERENCES
IX APPENDICES
A Incurred Material Preparation Costs A-l
B Revenue and Diverted Disposal Values B-l
C Collection Model C-l
D Separate Truck Systems Analyses D-l
E Rack Systems Analysis E-l
IV
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FIGURES
No. Page
1 Household source separation activities. 8
2 Participation rate as a function of socio- 21
economic status.
3 Separate truck related collection activities. 34
4 Participation rate as a function of separate 43
collection frequency.
5 Participation rate as a function of program 45
duration.
6 Fully allocated cost profile of separate truck 55
subsystems.
7 Impact of optimizing refuse collection opera- 68
tions: exemplary analysis, 3 man mixed refuse
collection performed once per week, 3 man sep-
arate collection crew.
8 Impact of optimizing refuse collection opera- 69
tions: exemplary analysis, 3 man mixed refuse
collection performing once per week, 2 man sep-
arate collection crew.
9 Impact of optimizing refuse collection opera- 70
tions: exemplary analysis, 1 man mixed refuse
collection performed once per week, 1 man sep-
arate collection crew.
10 Impact of optimizing refuse collection opera- 71
tions: exemplary analysis, 3 man mixed refuse
collection performed twice per week, 3 man sep-
arate collection crew.
11 Impact of optimizing refuse collection opera- 72
tions: exemplary analysis, 3 man mixed refuse
collection performed twice per week, 2 man sep-
arate collection crew.
12 Impact of optimizing refuse collection opera- 73
tions: exemplary analysis, 1 man mixed refuse
collection performed twice per week, 1 man sep-
arate collection crew.
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FIGURES
Rack configuration used in Madison, Wisconsin
for separate collection of newspaper.
14 Rack related collection activities.
15 Effective cost for rack collection of sep-
arated newspaper versus combined refuse
collection cost prior to system implementa-
tion: exemplary analysis for short haul
situation.
16 Effective cost for rack collection of sep-
arated newspaper versus combined refuse
collection cost prior to system implementa-
tion: exemplary analysis for long haul
situation.
Page
78
81
94
95
VI
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TABLES
No.
1 QUANTITIES OF RECYCLABLE AND NON-RECYCLABLE 9
MATERIALS
2 SUMMARY OP HOUSEHOLD TIME REQUIREMENTS FOR 11
SOURCE SEPARATION
3 HOUSEHOLDER SEPARATION TIME REQUIREMENTS 12
VERSUS QUANTITY OF RECYCLABLE MATERIAL
GENERATED
4 HOUSEHOLDER PREPARATION TIME VERSUS RE- 12
CYCLABLE MATERIAL VALUE
5 RECYCLABLE MATERIAL PREPARATION COSTS 14
6 RECYCLABLE MATERIAL STORAGE SPACE REQUIREMENTS 15
7 SEPARATE COLLECTION CASE STUDY LOCATIONS 18
8 SOURCE OF MOTIVATION FOR IMPLEMENTING SEPARATE 19
COLLECTION PROGRAMS
9 REASONS FOR IMPLEMENTING SEPARATE COLLECTION 19
PROGRAMS
10 INITIAL SEPARATE COLLECTION PUBLICITY COSTS 26
11 SEPARATE TRUCK COLLECTION PROGRAM BACKGROUND 32
12 SOURCE OF MANPOWER AND EQUIPMENT FOR 35
IMPLEMENTATION OF MUNICIPAL SEPARATE TRUCK
PROGRAMS
13 SEPARATE TRUCK COLLECTION EQUIPMENT AND 37
MANPOWER SUMMARY: MUNICIPAL PROGRAMS
14 SEPARATE TRUCK COLLECTION EQUIPMENT AND 38
MANPOWER SUMMARY: PRIVATE PARTY PROGRAMS
15 RATIO OF MIXED TO SEPARATE COLLECTION TRUCKS 40
16 DIVERTED DISPOSAL AS A FUNCTION OF SEPARATE 47
COLLECTION FREQUENCY: WASTEPAPER PROGRAMS
17 PERFORMANCE PROFILES FOR SEPARATE TRUCK 48
CASE STUDY LOCATIONS
V3.1
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TABLES (Continued)
No. Page
18 SEPARATE TRUCK PRODUCTIVITY FACTORS: 52
WASTEPAPER PROGRAMS
19 SEPARATE TRUCK PRODUCTIVITY FACTORS: 53
GLASS AND METAL PROGRAMS
20 EFFECTIVE FULLY ALLOCATED COSTS FOR SEPARATE 59
TRUCK OPERATIONS: WASTEPAPER PROGRAMS
21 EFFECTIVE FULLY ALLOCATED COSTS FOR SEPARATE 60
TRUCK OPERATIONS: GLASS, METAL, MULTI-
MATERIAL PROGRAMS
22 IMPACT OF SEPARATE COLLECTION ON OVERALL 63
RESIDENTIAL SOLID WASTE MANAGEMENT COSTS:
SEPARATE TRUCK APPROACH
23 CONDITIONS ANALYZED VIA THE ADAPTED REFUSE 66
COLLECTION. MODEL
24 RACK COLLECTION PROGRAM BACKGROUND 79
25 AMORTIZED STARTUP COSTS: RACK APPROACH 83
26 EQUIPMENT AND MANPOWER UTILIZATION: RACK 85
OPERATIONS
27 PERFORMANCE PROFILES FOR RACK SYSTEM CASE 86
STUDY LOCATIONS
28 ESTIMATED FULLY ALLOCATED COSTS AND SAVINGS: 90
RACK OPERATIONS
29 IMPACT OF SEPARATE COLLECTION ON OVERALL 92
RESIDENTIAL SOLID WASTE MANAGEMENT COSTS:
RACK APPROACH
Vl.ll
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SUMMARY AND CONCLUSIONS
Household Separation
Householder cooperation is necessary for source separation
of solid wastes. In order to quantify householder require-
ments, 20 volunteer households participated in special
studies during a two month period. Although the sampling
of households was too small to be representative of any
specific municipality or region, the primary conclusion
drawn with respect to householder efforts is of signifi-
cance:
Requirements for householder source separation con-
sume minimal amounts of time and are not costly.
Separate Collection Considerations
Separate collection of recyclable material should be con-
sidered a subsystem of the on-going residential refuse col-
lection system. There are two basic approaches to separate
collection: (1) a separate truck (or trucks) designated for
collection of separated materials, and (2) a rack (or racks)
mounted on a truck to isolate separated materials from mixed
refuse during collection. Regardless of approach, there are
several conclusions that should be drawn upon:
Public relations at the onset and during a separate
collection program is of crucial importance to
attain and retain citizen awareness and participa*
tion.
Enactment of an anti-scavenger ordinance is necessary
to provide a legal vehicle for curtailing unauthor-
ized collection of separated materials.
There is positive indication that community response
to a separate.collection program is related to the
socio-economic status within the service area.
Separate Truck Approach
As the name implies, the separate truck approach entails the
use of independent trucks and crews to collect recyclable
materials. Depending on the ability of a municipality to
divert labor and equipment from normal or reserve refuse
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collection operations, the frequency of separate collection
may be varied. Alternatively, some municipalities contract
with private parties for separate collection. The following
conclusions were drawn from the 17 case studies made of the
separate truck approach:
Three noteworthy issues were associated with house-
hold participation: (1) mandatory or voluntary pro-
gram status had little influence on householder par-
ticipation in the case study communities, (2) house-
holder participation increases with program dura*
tion, and (3) changing householder refuse set-out
habits from on-property mixed refuse collection to
curb collection for separate collection did not de-
crease participation.
Separate collection frequency was related to quanti-
ties diverted from disposal. The quantity of recy-
clable waste separately collected increased as sepa-
rate collection frequency increased, indicating a
willingness of householders to separate larger
quantities of recyclable waste if storage require-
ments are reduced.
Separate truck startup costs were minimal in the
case study communities. Modifications were made to
existing collection systems, diversions made from
other public works functions, or reserve forces were
utilized as sources of labor and equipment for sepa-
rate collection.
For a municipality desiring to implement a separate
collection program, wastepaper is the most economi-
cally feasible material to collect. Separate col-
lection of glass and/or metal cannot be performed
economically unless the municipality is able to
absorb the equipment and labor costs through use of
budgeted reserve forces.
Separate truck collection of recyclable materials,
as currently practiced, effectively reduced coverall
sblid waste management costs. If rerouting .of mixed
refuse collection vehicles were performed to -take
advantage of lesser quantities of waste, additional
cost savings could be obtained.
Rack Approach
The most appealing aspect of the rack approach was that mixed
refuse and separated materials can be collected simultaneously
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by the same crew. Householder refuse set-out habits need not
be altered. Based on five case studies made of the rack
approach, the following conclusions were drawn:
Startup costs for the rack approach are limited to
rack fabrication and installation.
The cost-effectiveness of the rack approach was
dependent on the flexibility of the mixed refuse
collection system to absorb incremental crew time
requirements (placing material in rack; transferring
material when racks filled prior to truck body fill-
ing with mixed refuse; and off-loading material at
the disposal site prior to dumping mixed refuse)
without creating a need for additional equipment and
labor. Rack case study sites were able to absorb
the incremental time requirements,and rack collec-
tion effectively reduced overall solid waste manage-
ment costs.
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II
INTRODUCTION
Increasing concern for protection of the environment and
the need to conserve diminishing resources has-revitalized
interest in recovering resources from solid waste. Closely
related to this renewed interest are projected depletion
rates and/or demand exceeding supply of some natural re-
sources. The paper industry, and, in particular, the news-
print faction are already succumbing to the pressures of
supply and demand. During 1973, Canadian International Paper
Company announced price increases totaling $35 per ton re-
sulting in a January 1974 price of $200 per ton to United
States consumers of newsprint. *• This 21.2 percent rise is
significantly higher than the annual industry average of
3.5 percent over the previous six years.2 Newsprint price
rises such as these are of great economic significance since
an estimated 65 to 70 percent of all newsprint used in the
United States is imported from Canada.2
Gauging the impact of supply and demand on domestically pro-
cessed paper prices is difficult due to the price
freeze. The U.S. Forest Service, however, has forecast a
severe pinch on timber supplies (including paper) coupled
with rapidly rising prices over the next few decades. As a
result of higher prices and demand forecasts exceeding pro-
jected .supplies, many newspaper publishers have announced
cutbacks in the size of publications and will likely raise
subscription fees and/or advertising rates.
In addition to projected virgin pulp shortages, increased
demands for wastepaper from Par East and European markets
have significantly influenced the value of domestic waste-
paper.2 f3 For example, in April 1973 used wastepaper col-
lected by municipalities was selling for under $10 per ton.
As of March 1974, wastepaper prices were as high as $56 per
ton in some areas of the United States.
Wastepaper price increases have not been mirrored by glass
and metal container salvage prices. This situation, in con-
junction with glass and metal representing smaller portions
of residential solid waste, has resulted in wastepaper being
most amenable to separate collection.
Closely paralleling the rise in wastepaper prices has been
an increase in the number of separate collection programs.
In 1967, the National Committee for Paper Stock Conservation
(American Paper Institute) approached Madison, Wisconsin,
Preceding page blank
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concerning participation in a pilot project to salvage and
recycle newsprint. Interests in increasing the supply of
good paper stock complemented city attempts to reduce the
solid waste volume entering the Madison sanitary landfill.
Thus, in 1968, the pilot project was implemented in the
eastern half of Madison with recovered tonnage averaging
about 80 tons per month through 1969. Changes in collection
procedures and expansion to a city-wide separate newspaper
collection program saw salvaged quantities rise to an aver-
age of over 240 tons per month in 1972.
For several years after initiation of the Madison experi-
ment, separate collection of recyclable materials was
fairly dormant. From 1970 to the present, however, over 100
separate collection programs have been initiated with about
three-fourths of this total originating since June 1973.
It was with respect to the upsurge of separate collection
programs that the U.S. Environmental Protection Agency,
Office of Solid Waste Management Programs, Resource Recovery
Division, contracted with SCS Engineers to obtain detailed
information on the performance and costs of operating these
resource recovery programs.
This report presents results of 22 case studies performed
on separate collection programs throughout the nation. In
addition to obtaining information on the recovery programs,
information was also sought to determine the time require-
ments for householders to separate and prepare recyclable
waste materials. Twenty SCS and EPA households conducted a
two-month study of recyclable material separation. Results
of the home studies are also reported.
The relationships developed and presented herein should be
considered as best estimates from the empirical data avail-
able since many variables between case study locations
could not be controlled.
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Ill
HOUSEHOLD SEPARATION OF RECYCLABLE MATERIALS
Householder cooperation is necessary for source separation
of solid wastes. Necessary householder activities are de-
picted in Figure 1 and are determined by material separa-
tion and preparation requirements of the separate collec-
tion service. For example, glass containers often must be
cleaned, the metal rings removed, and sorted by color; news-
papers often must be bundled or bagged; and metal containers
may be accepted only if cleaned and crushed, the labels re-
moved, and sorted by type of metal. Regardless of prepara-
tion requirements, all separated materials require interim
storage at the home prior to separate collection.
In order to quantify those household waste activities,
twenty SCS and EPA volunteer households participated in
special studies.* General demographic information relevant
to the participating households is summarized below:
The median gross annual household income was about
$20,000.
Twelve participants resided in single family-de-
tached houses, 5 in apartments, and 3 in condomin-
iums/townhouses.
The number of persons per household averaged 3.4.
The household survey period ranged from 4 to 10 weeks
and averaged 7 weeks.
Each household used prepared forms to record daily solid
waste generation data relevant to five recyclable waste
material categories1:
Glass (by color);
Tin/bi-raetal;
Aluminum;
Newspaper; and
All other solid waste (excluding yard trimmings).
*It should be noted that the findings presented in this
section are derived from too small of a sample to be
deemed representative of any specific municipality or
region. Rather, the findings are presented for general
interest and to express relative efforts and costs here-
tofore unquantified.
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Material Preparation Activities
f Residential
I Solid Waste
CO
Household
Separation
Recyclable
Materials
Cleaning
Contaminant
Removal
Volume
Reduction
Sort
Material
I
Transport
to Storage
Area
Other
Processing
(e.g. Bundling)
Material Storage
I
Figure 1. Household source separation activities.
Storage
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The data forms were also used to record time requirements
per material associated with the activities shown in Figure
1. Other data collected included storage requirements, sup-
plies, and resources used (e.g., twine for bundling and
water for cleaning).
Material Generation
Table 1 presents the average quantities of recyclable and
non-recyclable materials generated per person per day, and
per household per week. The definition for recyclable mate-
rials was based on an initial screening of over 60 recycling
operations (separate collection programs and collection cen-
ters) and limited to those materials most commonly accepted
(i.e., glass, tin/bi-metal, aluminum, and newspaper). Thus,
excluding yard trimmings, non-recyclable materials were de-
fined as all other residential solid waste. Potentially
recyclable items such as corrugated cardboard, textiles,
and possibly food wastes are admittedly penalized under this
definition.
Tabular results show that nearly equivalent quantities of
recyclable and non-recyclable materials were generated dur-
ing the survey period.
TABLE 1
QUANTITIES OF RECYCLABLE AND
NON-RECYCLABLE MATERIALS*
Non-
Recyclable Materials (Ibs) Recyl.
Mate-
Tin/Bi- News- rials Total
Glass Metal Alum, paper Total (Ibs) (Ibs)
Ibs/cap/day 0.19 0.07 0.01 0.51 0.78 0.83 1.61
Ibs/house-
hold/wk 4.5 1.7 0.3 12.2 18.7 19.8 38.5
* Excludes yard trimmings.
Adding the daily per capita generation rates for recyclable
materials (0.78 Ibs) and non-recyclable materials (0.83 Ibs)
equates to a total of about 1.6 Ibs for the participating
households. This sum was significantly less than published
9
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national figures of 2.5 Ibs per person per day, and a Los
Angeles figure of 2.1 Ibs per person per day (half of the
household studies were conducted in the Los Angeles area).
As previously defined, however, waste quantities excluded
yard trimmings. In Los Angeles, yard trimmings comprise
about 33 percent (by weight) of the total residential solid
waste collected and disposed.4
Nationally, the American Public Works Association estimates
that average municipal refuse contains 12 percent (by weight)
of yard type waste.5 The percentage expressed in terms of
only the residential portion of municipal refuse would
likely be higher. Thus, the overall generation rate re-
corded during the household study appears appropriate when
all factors are considered.
Thus, separated material weight represented about one-third
of the solid waste emitted from each household.
Material Preparation
Weekly time requirements per household for the activities
associated with preparing recyclable materials for separate
collection are summarized in Table 2. The total of 15.9
minutes per week to prepare all the materials averaged to
about 2 minutes per day.
Table 3 presents a comparison of the preparation time re-
quirements in terms of material quantity. Newspaper re-
quired the minimum amount of preparation time per unit
weight of material and was, thus, the most efficient mate-
rial for the householder to separate. In essence, bundling
was the only significant time requirement. Bundling was
normally accomplished in one of two ways: tying string or
twine around newspapers, or stuffing newspapers in grocery
bags.
Glass was the second most efficient material to separate.
Cleaning and contaminant removal were the major time con-
tributors. The least efficient materials to separate were
metallic. Aluminum containers were low generation items
although preparation time was proportionately high due to
cleaning, contaminant removal, and volume reduction activi-
ties being performed prior to storage. Tin/bi-raetal mate-
rial, preparation time requirements were highest because of
time required to flatten containers. While aluminum con-
tainers were readily crushed, flattening tin/bi-aetal con-
tainers necessitated removal of the can bottom.
10
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TABLE 2
SUMMARY OF HOUSEHOLD TIME REQUIREMENTS FOR SOURCE SEPARATION
Average Preparation Time
Material Preparation Operation Glass Tin/Bi-Metal
Clean*
Contaminant removal
Volume reduction
Bundle
. Transport (in home)
Total
2.4
0.6
0.0
N.A.
1.6
4.6
2.3
1.1
2.2
N.A.
1.4
7.0
Aluminum
0.7
0.1
0.2
N.A.
0.3
1.3
(Min/Wk)
Newspaper
N.A.
0.1
N.A.
2.3
0.6
3.0
Total
5.4
1.9
2.4
2.3
3.9
15.9
N.A. = Not Applicable
*Includes time for material sorting
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TABLE 3
HOUSEHOLDER SEPARATION TIME REQUIREMENTS VERSUS
QUANTITY OF RECYCLABLE MATERIAL GENERATED
Material
Glass
Tin/bi-metal
Aluminum
Newspaper
Householder
Preparation Time
(% of Total Time)
29
43
9
19
Quantity Separated
(% of Total Weight)
24
9
1
66
Time to
Weight
Ratio
1.2
4.8
9.0
0.3
Viewed in terms of material value, (April 1973 revenue
rates), Table 4 shows that preparation of newspaper and
aluminum had greatest worth in terms of householder efforts-
eight cents per min of preparation. Glass preparation had
half of the newspaper/aluminum worth, while tin/hi-metal
had the lowest worth ratio - less than a penny per min of
householder effort. During 1974, revenue for newspaper and
aluminum experienced appreciable increases. Newspaper, how-
ever, had a proportionately greater increase such that the
monetary return on invented householder effort wa$ greater.
Thus, in terms of efficiency and worth, newspapersappears
to be the optimum material in terms of householder source
separation requirements.
TABLE 4
HOUSEHOLDER PREPARATION TIME VERSUS
RECYCLABLE MATERIAL VALUE
Material
Value*
($/ton)
Material
Glass
Tin/bi-metal
Aluminum
Newspaper
April
1973
20
15
200
8
March
1974
20
300*
30
Householder
Preparation
Effort
(Min/Ton)
500
2,000
2,600
100
•II1- • - - ;
Monetary JReturn on
Householder Effort
5$/min of* effort)
April
1973
0.04
0.01
0.08
0.08
March
1974
0.04
0.01
0.12
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Material Preparation Costs. Material preparation costs were
defined as the incremental costs incurred by a householder
for supplies or resources used while separating and prepar-
ing recyclable materials. Included in this definition would
be water used for cleaning, energy used if metal container
volume reduction was accomplished with the aid of an elec-
tric can opener, and twine used when bundling newspapers.
Implied costs of householder time were excluded.
Participants in the household study did not use soap for
cleaning separated containers unless the soap was contained
in used dishwater. Similarly, mechanical dishwashers were
not used for cleaning containers. Thus, no incremental
costs were assigned for soap or dishwasher use.
Incurred material preparation costs are presented in Table 5.
The preparation cost per ton varied by material and ranged
from zero when no preparation activities were performed to a
high of about $2.30 per ton for cleaning and flattening
aluminum containers. Expressed as a household cost per
month, about $0.02 per month would be expended if all mate-
rial were prepared for separate collection. A detailed
derivation of the incurred costs is provided in Appendix A.
Comparing Tables 3/ 4, and 5 presents an interesting inverse
relationship. While newspapers were the most efficient and
worthwhile material to separate, they were also the most
costly to prepare. At about one penny per month, however,
the cost of preparation should not deter household partici-
pation.
Material Storage
The floor area used to store separated materials during the
household study was defined as the amount of floor space
consumed by containers used to store materials or to stack
newspapers. Consequently, the storage area requirement was
a function of separated material generation rates and the
accumulation time between removal by a separate collection
program. The type of material and the amount <5f volume
reduction practiced were also factors in storage area re-
quirements. Newspapers, for example, when bundled and
stacked, do not require any additional floor space for a
one-week versus a one-month accumulation period. Glass
accumulations, however, usually required additional floor
space for storage as the accumulation period lengthens
because it is potentially hazardous to practice glass vol-
ume reduction in the home. Tin/bi-metal and aluminum mate-
rials storage space requirements were dependent on the
amount of volume reduction practiced.
13
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TABLE 5
RECYCLABLE MATERIAL PREPARATION COSTS
Material
Glass
Tin/bi.-metal
Aluminum
Newspaper
Range in Material
Preparation Cost
($/ton)
0 to 0.53
0 to 1.45
0 to 2.33
0 to 0.43
Average
Material
Generation
Rate*
(Ibs/mo)
19.3
7.2
1.3
52.8
Time Required
to Accumulate
One Ton of
Material Per
Household* (mo)
104
278
1,538
38
Range in Material
Preparation Cost
($/household/mo)
0 to 0.005
0 to 0.005
0 to 0.002
0 to 0.011
*Based on generation rates determined from household study.
+Rounded to nearest month.
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Based on household study data, Table 6 presents the average
floor space required for storage of each type of separated
material. The household accumulation period averaged one
month. Data were not amenable to further breakdown.
TABLE 6
RECYCLABLE MATERIAL STORAGE SPACE REQUIREMENTS
(One Month Accumulation Period)
Glass
(sq ft)
2.2
Tin/Bi-Metal
Volume
Reduction
(sq ft)
1.6
No Volume
Reduction
(sq ft)
2.8
Aluminum
Volume
Reduction
(sq ft)
1.8
No Volume
Reduction
(sq ft)
1.9
News-
paper
Stacked
(sq ft)
3.3
Incurred Material Storage Costs. Based on the household
study and information obtained during the nationwide case
studies, storage containers used by householders for sepa-
rated materials were generally of a makeshift nature (e.g.,
cardboard boxes or grocery bags). Similarly, existing space
was used for storage of recyclable materials. Thus, for all
practical purposes, there were no incremental costs incurred
by householders for storage of separated materials.
15
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IV
SEPARATE COLLECTION CONSIDERATIONS
Separate collection of recyclable material should be con-
sidered a subsystem of an on-going residential solid waste
collection system. There are currently two basic approaches
to separate collection: (1) a truck (or trucks) designated
for independent collection of separated materials, and (2) a
rack (or racks) mounted on a truck to isolate separated mate-
rials from the mixed refuse during collection. Case studies
were made at 17 locations employing the separate truck ap-
proach and five locations using the rack approach.
The case study locations are identified in Table 7, along
with the recyclable materials separately collected. The
major portion of the case study results will be geared
toward the paper programs. Not only were there more data
available on the paper programs, but, as will be discussed,
the paper programs appear to be the most economically feasi-
ble.
Prior to an assessment of the two alternative approaches to
separate collection, an overview of considerations applica-
ble to either approach will be presented. These include the
rationale for initiating separate collection programs; socio-
economic considerations; public response; public relations;
need for an anti-scavenger ordinance; and material prepara-
tion requirements.
Program Initiation
The source of motivation and reasons for implementing the 22
separate collection programs studied are summarized in Tables
8 and 9. Program motivation was influenced by local citi-
zenry as much as by municipal officials. Academic and in-
dustrial sources provided lesser, but significant, motiva-
tion. Citizen movements were typically local ecology groups
and/or civic interest groups such as the American Associa*
tion of University Women, the League of Women Voters, and
philanthropic or service clubs.
Seventy-three percent of the case study locations cited the
desire to reduce solid waste quantities for disposal as the
reason for starting separate collection. Assessment of com-
munity interest in recycling was the second most prevalent
reason. The desire for financial profit from separate col-
lection of recyclable materials was not cited as a reason
for implementing the separate collection programs. The
Preceding page blank
17
-------
TABLE 7
SEPARATE COLLECTION CASE STUDY LOCATIONS
Materials Separately Collected
Case Study Type/Location Paper Glass/Metal
Separate Truck Approach
Bedford, Mass. X X
Bowie, Md. X X
Briarcliff Manor, N.Y. x
Cincinnati, Oh. X
Dallas, Tex. X
Ft. Worth, Tex. X
Great Neck, N.Y. X
Green Bay, Wise. X X
Greenbelt, Md. X
Hempstead, N.W. X
Marblehead, Mass. X X
Newton, Mass. X
Reston, Va. X
Tuscon, Ariz. X X
University Park, Tex. X
Villa Park, 111. X
West Hartford, Conn. X
Rack Approach
Chicago, 111. X
Madison, Wise. X
New York, N.Y. X
San Francisco, Calif. X
Sheboygan, Wise. X
18
-------
TABLE 8
Response
Number*
Percent**
SOURCE OF MOTIVATION FOR IMPLEMENTING
SEPARATE COLLECTION PROGRAMS
Source
Municipality Citizenry School Industry
12
55
12
55
4
18
3
14
*22 total respondents (i.e., case study Sites). Multi-
ple sources cause the sum to exceed the total number
of respondents.
**Multiple responses cause the sum to exceed 100 percent.
TABLE 9
REASONS FOR IMPLEMENTING
SEPARATE COLLECTION PROGRAMS
Response
Number*
Percent**
Reason
Assess Combat Rising Demonstrate
Reduce Community Solid Waste Municipal
Disposed Interest in Management Environmental
Quantities Recycling Costs Concern
16
73
7
32
4
18
4
18
*22 total respondents (i.e., case study sites). Multi-
ple reasons cause the sum to exceed the total number
of respondents.
**Multiple responses cause the sum to exceed 100 percent.
19
-------
influx of about 100 separate collection programs from Fall
1973 through Spring of 1974, however, is likely related to
a rise in recyclable paper prices-as much as $25 to $56 per
ton depending on the local market conditions. Thus, eco-
nomic considerations now probably play a more important role
than indicated by the case study responses.
Spcio-Econgmic Considerations
At the onset of the project, socio-economics were hypothe-
sized as an explanatory variable for program success predic-
tions. When the case studies were conducted, however, none
of the selected sites were able to provide quantitative
socio-economic information on the areas served by separate
collection programs.* Qualitatively, only Green Bay, Wis-
consin attributed participation rates to socio-economic
criteria. In th£ Green Bay pilot area, 40 percent of the
residents were designated as highly transient and of lower-
middle economic status. The remainder of the pilot area
was judged to have been 43 percent middle class and 17 per-
cent Cupper class. Green Bay representatives stated that
participation was less in the transient/low income sector
when compared to the more affluent sectors of the pilot
area.
Without quantitative data to analyze, a qualitative socio-
economic assessment of each case study location was obtained
where possible to reflect a cross-section of the area served
by the_separate collection program (i.e., lower, lower-mid-
dle, middle, upper-middle, or upper economic status). These
assessments were compared to the program participation rate*
with th-s results s.hown in Figure 2. As shown, there appears
to be positive; indication that socio-economic status is
*Many of the 'separate collection service areas were not
amenable £q census data. As a result, knowledgeable
personnel at each case study location were asked to
assess the socio-economic status within the service
area.
^Participation rate is defined as the number of house-
holders, expressed as the percent of residents in a
separate collection service area, placing recyclable
material out for collection during the time of the case
s tudy.
20
-------
NJ
c
o
•H
4J
di
•H
0
•H
"H
frt
'U
cu
•4J
£
QJ
O
tl
r^
04
1 f\ f\
100
90
80
70
60
50
40
30
on
£•• V.
Ki
1
_
*
•
.
0
Percent Participation = -11.8 +29.0 (Socio-Economic Status*)
Coefficient of Correlation = 0.8
*Based on numerical assignment of:
Middle = 1 I—Band of Relevancy -J
Upper-Middle ~ 2
Upper = 3
i
• Bowie
s
/
• Great Neck
^
x
/
/\
/•West Hartford
•Briarcliff Manor
•Bedford
/ • Hemps te ad
•Madison .
X
•Ft. Worth ^ Marblehead
^•Newton, University Park
/ i
1 /" •Res ton
• Green •Dallas
A "ay •san Francisco
/i Villa Park
/ Icincinnati
T Sheboygan
, , •New York ,
Lower Lower Middle Upper Upper
Middle Middle
Socio-Economic Status of Separate Collection Area
Figure 2: Participation rate as a function of socio-economic status
-------
important to achieving program success.* Although the data
plotted in Figure 2 is subjective, thus making the statisti-
cal validity shown questionable, the trend is of signifi-
cance .
During the time between performance of the case studies and
publication of this report, the University of Wisconsin
graduate School of Business released the results of a socio-
economic study of voluntary users and non-users of the Madi-
son recycling center and participation in the separate col-
lection program.6 The results are of significance and
should be considered by communities when assessing the feasi-
bility of a separate collection program. The study con-
cluded that the major differences between users and non-
users were:
Over half the recycling center non-users had gross
annual incomes of under $10,000 while the majority
of the users earned over $14,000.
. Occupation of the family head was strongly related
to recycling center use. Thirty-nine percent of the
user family heads were professionals (i.e., lawyer,
medical doctor, professor, engineer, etc.) as com-
pared to 10 percent for the non-user families.
Education of the family head and wives revealed the
strongest relationship of user criteria examined.
Seventy-three percent of the family heads and 59
percent of the wives in user homes had four or more
years of college. Comparatively, 34 percent of the
non-user family heads and 22 percent of the wives
had four or more years of college. Further, 41
percent of the non-user family heads had four years
of high school or less as compared to 13 percent of
the user family heads.
In terms of saving newspaper for the Madison sepa-
rate collection program, education was strongly
correlated. When the family head had four or more
*Three programs were purposely excluded from Figure 2:
The Greenbelt, Maryland program was not included due to
municipal officials being unable to place any degree of
confidence in the participation rate being attained due
to a predominance of cluster housing and common collec-
tion points. The Chicago, Illinois program foundered
due to scavenger problems and the Tucson, Arizona
program was a subscription service.
22
-------
years of college, 93 percent saved newspapers for
recycling. When the family head had four years of
high school or less as a maximum education level,
only 60 percent saved newspapers.
Two other points highlighted in the Madison study were also
of interest: there was no relationship found between the
number of children under 18 and use of the recycling center.
Nor was age of the family head found to be a factor. The
study had hypothesized that recycle center users would have
more children and be younger. Neither hypothesis was sup-
ported by the study data.
In spite of the fact that family head age was not found to
be significant in Madison, age may be influential in deter-
mining the amount of paper available for separate collec-
tion.
Although not a case study location, the Fullerton, Califor-
nia* separate newspaper collection program was observed dur-
ing the first several months of operation. It was observed
that areas of the city housing senior citizens were not
generating newspaper at a rate proportional to the city as
a whole. Although participating in the program, persons on
fixed incomes or pensions appeared not to subscribe to daily
newspapers to the normal degree. Paper placed out for col-
lection was generally composed of a local weekly newspaper
and "junk mail" printed on newsprint. This phenomena may be
significant to a municipality assessing the feasibility of a
separate collection program where a large portion of the
residents are of the status described.
Public Response
Several attitudinal studies have measured the positive de-
sires of householders to participate in recycling efforts
by separating their refuse. For example:
"Virtually all metropolitan housewives (90%) express
willingness to separate their trash to facilitate
recycling. About half feel that such activity
should be mandatory rather than voluntary. Were
separation of trash required, however, housewives
claim they would prefer to have it done at the
*The Fullerton, California separate collection program
commenced September 1973; after the case studies con-
tributing to this report had been concluded.
23
-------
household level rather than pay even a minimal ($1-
a-year) fee to the municipality to have it done for
them."'
"While most Toledo, Ohio, residents appear unwilling
to accept increases in family expenses or reduction
in standard of living in order to minimize environ-
mental pollution, an overwhelming majority would be
willing to purchase only returnable beverage con-
tainers and separate paper and other refuse for re-
cycling. Asked if they would be willing to separate
their own trash into recyclable paper, cans, bottles,
and garbage, 82% of the pollution-conscious group
said yes, 12% were undecided and 6% said no. Of the
less-concerned group, 91% said yes, none were unde-
cided, and 9% said no. Of the less-concern«d group.
93% said yes, none were undecided, and 7% said no.n<>
. A nationwide polling showed that 71% of the respon-
dents were willing to collect and save old news-
papers for recycling, while 55% were willing to sort
trash at home to facilitate recycling.9
Prior to implementing the separate newspaper collec-
tion progaam in the New York case study area, 20% of
the householders indicated a desire to participate.
The average participation rate achieved was 2% upon
commencement of the rack program.
Overall, the 22 case study locations had participation rates
ranging from 2 to 75 percent with an average of under 40 per-
cent. Thus, it appears that a significant gap exists be-
tween what people say versus what they practice.
Public Relations
Public relations at the onset and during a separate collec-
tion program has been found necessary to attain and retain
participation.
Announcements of the program should precede the implementa-
tion date by a month or more and outline the program goals,
provide rationale for separate collection, present collec-
tion schedules, etc. During the interim period between
initial announcement and implementation, continual reminders
should be made through the local media (articles in news-
papers, spot announcements on radio and television). In
addition, notices in utility billings, printed door knob
hangers, and announcements made to/by local civic/service
groups are often used for initial and on-going publicity
purposes.
24
-------
Eleven of the 22 case study sites kept records of initial
publicity costs (see Table 10). Promotional efforts were
largely donated by civic-minded citizen/environmental
groups; however, "but of pocket"* expenditures averaged 10
cents per household in the separate collection area with a
range of a penny to 33 cents per household.
Although coincidental, a difference existed in initial pub-
licity expenditures between the average separate truck pro-
gram (5 cents per household) and the average rack program
(15 cents per household). Initial publicity efforts for
each differed only in the technique of distributing publi-
city materials to householders. The separate truck programs
used a combination of mailing and distribution of door knob
hangers and publicity flyers by youth groups. The youth
groups were paid at the rate of about one cent per household,
The three rack programs with cost records used city em-
ployees exclusively to distribute door knob hangers and
flyers, thus accounting for the threefold cost difference.
None of the case study sites maintained appropriate cost
records for on-going publicity efforts although each site
stated the importance of constant public reminders. The
effect of terminating publicity efforts following program
initiation was demonstrated in the New York case study
(Queens Sanitation District 67 only). An extensive initial
publicity campaign resulted in 22 tons of separated news-
paper the first month of the program. By the sixth month,
however, quantities had declined to only three tons. Offi-
cials stated that publicity in Queens District 67 had lagged
due to publicity requirements in other districts. The offi-
cials indicated that in other areas of the city, program
participation would respond favorably to reminders and then
tail off; thus indicating the need for a continuous publi-
city program.
There were several methods used by the case study programs
for on-going publicity. Reminders in utility billings,
weekly series in local papers, and program goals or themes
were used effectively.
*0ut-of-pocket expenditures include only those costs in-
curred by the case study program. Donated time or inkind
service costs were not quantified due to lack of data
maintained at case study locations.
25
-------
TABLE 10
INITIAL SEPARATE COLLECTION PUBLICITY COSTS
Case Study Location
Separate Truck Approach
Bedford, Mass.
Ft. Worth, Tex.
Green Bay, Wise.
Greenbelt, Md.
Marblehead, Mass.
Reston, Va.
University Park, Tex.
Villa Park, 111.
Subtotal
Initial
Cost*
(?)
180
1,000
400
600
400
65
610
50
$3,305
Residences
in Separate
Collection
Area
(No.)
3,200
22,620
2,000
6,100
7,600
7,550
8,280
6,470
63,820
Initial
Cost Per
Residence
($/Res)
0.06
0.04
0.20
0.10
0.05
0.01
0.07
0.01
0.05
Rack Approach
Chicago, 111.
Madison, Wise.
New York, N.Y.
Subtotal
Total
380
6,030
2,400
$8,810
$12,115
1,160
41,000
15,350
57,510
121,329
0.33
0.15
0.16
0.15
0.10
*0ut-of-pocket costs only. Does not include costs for
donated or inkind services or materials.
26
-------
Scavenger* Problems
Scavenger problems have a higher probability of occurrence
when market prices are high. With the recent rise in waste-
paper prices, separate paper collection programs have become
a target for many scavengers.
Scavenger problems were evident in Cincinnati, Hempstead,
and Chicago. At the time of the case studies, Cincinnati
had the highest revenue rate of any program visited - $14.20
per ton. Wastepaper dealers in Cincinnati reported a 100
percent increase in supply after implementation of the
separate collection program, yet municipal trucks accounted
for only 25 percent of the increase. Thus, program effec-
tiveness, from the point of generating revenue for the city,
was severly hampered. Cincinnati had no recourse as scaven-
gers were licensed and within their rights to collect; the;
separated paper prior- to city collections being performed.
Scavenger problems were also critical in Chicago where
again, no ordinances prohibited such activity. During three
months of operation, less than 15 tons of newspaper had been
collected by the municipality in a pilot area of about 3,000
residences. A survey of scavengers by city officials indi-
cated that residential participation was as high as 75 per-
cent at the onset of the program. City officials were not
concerned that scavengers collected and sold the separated
newspapers as the primary goal of the program was to reduce
the volume of waste to be incinerated, not to obtain reve-
nue from the sale of the newspaper.
Other case study locations had instituted ordinances making
separated paper the property of the designated collector.
Hempstead provided a good example of the effect of price
rise on scavenger operations and the positive effect of an
ordinance. At the time of the case study Hempstead was re-
ceiving $9 per ton for newspaper collected and delivered to
the paperstock dealer. At the $9 price scavengers were not
active. When paper prices reached $17 per ton, Hempstead
began losing about 40 percent of the paper to scavengers
(100 tons per month). To combat the problem, Hempstead im-
plemented provisions of an existing scavenging ordinance.
A crackdown was initiated by sanitation inspectors who pat-
rolled the hardest hit areas at night and in the early morn-
ing hours in radio-equipped cars. Six summons were issued
*In some locations, licensed haulers are designated as
"scavengers." The scavengers referenced herein are
unauthorized and, often, unlawful collectors of recy-
clable materials designated for separate collection.
27
-------
during the first month of patrol. The six cases were pend-
ing at the time of this report. If convicted, the scaven-
gers can be fined $250 and receive up to 15 days in jail.
The crackdown has resulted in a significant drop in scaven-
ger activity.
Almost all separate collection programs can expect some
scavenging. An anti-scavenger ordinance is therefore neces-
sary as a legal vehicle to control scavenging activity. How-
ever, the manner and cost of policing the ordinance should
be considered by program officials.
Material Preparation Requirements
Proper preparation of recyclable materials for separate col-
lection is imperative for efficient operations. Preparation
requirements were similar in the case study locations.
Paper. Preparation requirements for newspaper or mixed
paper required the materials to be contaminant free and
bundled with string/twine or stuffed into paper grocery
bags.
Paper contamination is based on ultimate use. For example,
if separated paper is to be reused as newsprint, paper pro-
ducts other than used newspaper would be contaminants.
However, if the end use is combination board, insulation,
or asphalt shingles, almost any form of wastepaper is accep-
table (excluding wax or plastic coated paper products).
Bundling is required to minimize litter and to facilitate
handling during collection. The impact of unbundled paper
on collection operations was quantified during studies in
Fort Worth, Texas.7 Loading loose paper required from two
to three times longer when compared to bundled paper.
Although not a case study site, portions of San Mateo County,
California, receive separate newspaper collection service
via the rack approach.* A spokesman for the collection firm
commented on several drawbacks of using paper bags for bun-
dling. Paper tends to slip out of the bag if not tightly
stuffed, and the bag may rupture during handling operations
(initial loading in racks, unloading racks, loading into
transfer containers). These comments would also be appli-
cable for collections using the separate truck approach -
*San Mateo Scavenger Company, Inc., serving 11 cities
and several unincorporated areas in San Mateo, Cali-
fornit, initiated a separate newspaper collection pro-
gram in November 1973.
28
-------
more so with open truck operations than with enclosed com-
pactor vehicles. Thus, the use of string/twine for bundling
should be encouraged to facilitate efficient handling.
Glass. Glass preparation requirements entailed cleaning,
color sorting, contaminant removal, and containerization
prior to collection. Glass was normally collected at
:monthly intervals at the case study locations. Thus, clean-
ing was requested to eliminate pest and odor problems dur-
ing storage.
Color sorting was almost always required as the color
characteristics of recycled cullet often limit the flexi-
bility of reuse.
Contamination of recyclable glass is virtually constrained
to aluminum "neck rings" and metal foil hoods on some bever-
age containers. If allowed to enter the glass production
process, these contaminants reduce final produce strength or
cause color variations and, thus, must be removed.
Grocery bags were most commonly used as containers for sepa-
rated glass. Although no time studies were performed for
separate glass collection, the loose versus bundled paper
collection analogy would certainly exist. Because ruptured
bags could produce a hazardous collection condition, house-
holders should be cautioned about using defective grocery
bags and instructed not to overload a bag.
Metal. Although separated aluminum containers have a higher
resale value than tin or bi-metal containers, the small
quantities available per household did not generally warrant
their independent separation. Metal preparation require-
ments generally consisted of cleaning, label removal, flat-
tening, and containerization for ease of collection.
Cleaning was required for the reason previously stated -
elimination of pest and odor problems during storage.
Label removal is a function of ultimate use. When label re-
moval is required from tin containers, a chemical process is
normally performed to recover the tin whereupon the stripped
metal container is sold as scrap. If no label removal is
required, tin/bi-metal containers are normally incinerated
to remove labels and lacquered coatings with the resulting
metal sold to the copper mining industry.
Flattening was required only to minimize storage space dur-
ing collection when open trucks were used. When compactor
trucks were used there was no requirement to flatten metal
containers.
29
-------
Again, metal separated for collection were required to be
containerized. Grocery bags were most commonly used for
this purpose.
30
-------
V
SEPARATE COLLECTION: SEPARATE TRUCK APPROACH
As the name implies, the separate truck approach entails
the use of independent trucks and crews to collect recy-
clable materials. Seventeen separate truck programs were
studied to obtain operational and cost information. Table
11 provides descriptive information on the case study pro-
grams .
The population of the case study locations varied greatly:
seven had populations of less than 25,000; five others
ranged from 25,000 to 100,000; three had from 100,000 to
500,000 residents; and two were in the 500,000 to 1,000,000
population range. Of the five cities with total population
greater than 100,000, only Cincinnati and Hempstead pro-
vided separate collection service to a major portion of the
total. The programs in Dallas, Fort Worth, and Tucson were
operated in pilot areas only. Full-scale programs were
operated in all twelve locations with populations under
100,000.
The number of residents per household averaged about 3.6 in
the separate collection areas. Socio-economic status of the
separate collection areas reportedly ranged from middle
to between upper-middle and upper.
Most of the programs were relatively new at the time of case
study*: the duration of the average program was only about
14 months. Eight had been in operation one year or less,
six others between one and two years. Only two had been
operating for a two year or longer period.
Each separate truck program collected newspaper. Seven pro-
grams also accepted other recyclable wastepaper (corrugated
cardboard, bond, etc.). Where mixed paper was collected,
newspaper still comprised the bulk of the quantities avail-
able for collection. For example, in Fort Worth, the mixed
paper quantities were estimated to be 80 percent newspaper,
15 percent corrugated cardboard, and 5 percent other recy-
ciable paper. Only five locations collected glass and/or
metal.
Separate collection responsibility was municipal in 11 loca-
tions while six were operated either by citizen groups,
*Case studies were conducted in March and April 1973,
-------
(A)
NI
TABLE 11
£EPAEATJ3 TRUCK jQOLLECTXON PROGRAM BACKGROUND
Case study location
Population
(thousands) *
Served by
Total sop. coll'
Bedford, Mass.
Bowie, Md.
Briarcliff Manor, N.Y.
Cincinnati, Oh.
Dallas, Tex.**
Ft. Worth, Tex.**
Great Neck, N.Y.++
Croen Bay, Wise.**
Greanbelt, Md.
Hempstead, N.Y.
Marblohead, Mass.
Newton, Mass.
Res ton, Va.
Tucson, Ariz.**
University Park, Tex.
Villa Park, 111.
U'est Hartford, Conn.
10
40
10
450
900
400
10
90
20
850
20
90
20
400
20
30
70
10
40
10
230
60
90
10
90
20
840
20
90
20
***
20
30
70
Materials
Pi-n
-------
paper stock dealers or, in Tucson, by a newly formed private
company. The Bowie program had both - glass and metal was
separately collected by municipal crews, newspaper by a
volunteer group.
The non-municipal approach was conducted in six relatively
small communities (average population about 20,000}. In
communities of this size, volunteer groups or other private
entrepreneur approaches may be feasible as equipment and
manpower requirements are often small.
Five of the programs studied were legislated via a local
ordinance which required householders to separate certain
materials for collection. Twelve programs offered separate
collection service to householders who voluntarily separated
specified materials.
Separate Truck Activities
The activities associated with the separate truck approach
are diagramed in Figure 3. The activites associated with
the collection of recyclable paper differed somewhat from
glass/metal container collections. The former were typi-
cally transported directly to the secondary materials dealer
without interim processing or storage. However, the sepa-
rate glass/metal collection programs stored materials until
sufficient quantities had accumulated for efficient trans-
port to a secondary materials dealer.
Green Bay was the only location practicing material pro-
cessing - glass was crushed to increase density. This im-
proved transport efficiency to the glass dealer located
approximately 150 miles from the collection area.
Startup Costs
Startup costs in almost every location were negligible.
Initial publicity costs averaged 5 cents per residence
served. Initial equipment and labor costs were similarly
low. In the case of private collectors, all collection
vehicles (either open stake trucks or enclosed vans) were
owned prior to commencement of the separate collection pro-
grams. The driver was either the owner or a full-time em-
ployee. Loaders were generally part-time employees hired
on an "as needed" basis.
Municipal collection startup costs were similarly low. As
shown in Table 12, Marblehead and Newton were the only muni-
cipalities requiring additional personnel for program
33
-------
HOUSEHOLD RELATED ACTIVITIES
SEPARATE TRUCK COLLECTION RELATED ACTIVITIES
•~l
W
(RESIDENCE}
/RESDENTIALT1
ISOUD WASTE
1 HOUSE
SEPAR
HOLD
ATION
)
RECYCLABLE.
MATERIALS
NON- RECYCLABLE
MATERIALS
HOUSEHOLD
PROCESSING
STORAGE
HOUSEHOLD
STORAGE
1
,
'
-i PREDOMINANT PATH PAPER
SEPARATE
TRU6K
COLLECTION
^sepwwsffi.
COLkECTtOH
PREDCMNANT PATH GLASS, METAL
t
PROCESS 1 STORE
MATERIALS (MATERIALS
TRANSPORT
TO
.SECONDARY
MATERIALS
DEALER
XDEALER/
3. Sfepatat:e TtucJt Rfeiatftd Coil^Ct±on
-------
TABLE 12
SOURCE OF MANPOWER AND EQUIPMENT FOR
IMPLEMENTATION OF MUNICIPAL SEPARATE
TRUCK PROGRAMS
Case
study
location
Existing resources
Incremental requirements
Modification
to existing solid
waste collection
system
Diverted from
other public Reserve
works functions forces
Part-time
labor
New equipment
purchase
Bowie, Md.
Cincinnati, Oh.
Dallas, Tex.
Ft. Worth, Tex. X
Great Neck, N.Y.
Green Bay, Wise. X
ui Greenbelt, Md.
Hemps tead, N.Y.
Marblehead, Mass.
Newton, Mass.
University Park, Tex.
West Hartford, Conn. X
X
X
X
X
X
X
X
X
X
X X
X X
X
-------
implementation (both locations used part-time hires to sup-
plement existing crews) ; and only the West Hartford program
required the purchase of incremental equipment (a 20 cu yd
rear- loading compactor) . in every other municipal case
study location, either modifications had been made to exist-
ing collection methods, thus freeing crews and equipment for
separate collection? equipment and labor had been diverted
from other public works functions; or reserve equipment and
labor forces were utilized.
For example, Fort Worth modified mixed collections to pro-
vide curb service using plastic bags rather than backyard
service. A surplus in collection equipment and labor re-
sulted, and two crews were diverted for a pilot separate
collection program. Dallas and University Park both col-
lected residential refuse four days per week with necessary
brush and bulky collections made on Wednesdays by part of
the brush collection crew. These crews were also used for
the respective separate collection programs. Cincinnati
was one of six municipalities to use reserve equipment and
labor for separate collections.
Although the minimal case study startup costs present an
optimistic outlook, there is a limit to which trucks and
crews can be diverted from regular duties. The limit will
vary from location to location thus requiring an individual
assessment. For example, the pilot program in Fort Worth
initially employed two extra crews for separate collections.
The pilot program proved to be a success and a city-wide
program was planned for June 1974 implementation. However,
the city-wide expansion will not benefit from the previously
described system modification; thus, new trucks have been
ordered specifically for separate collection.
Equipment and Manpower Utilization
The respective resources used for municipal and private
party separate truck programs are summarized in Tables 13
and 14. Municipal programs used rear-loading compactor
tolfcu vdSt ?xclusivelv*' with capacities LngTng f?om 10
to 28 cu yd. The non-compacting vehicles listed were usu-
ally borrowed rrom other public works functions wheT
*2L™S Averse comment to the use of compactors for
separate collection was voiced in Green Bay.. A pro-
flXal ated th
..
fated that sma11 fragments we re often
when glass was being compacted. This comment
.
s?Ln?o us.°f ln Maflehead' however, (the onyther
site to use a compactor for collecting glass) ,
36
-------
TABLE 13
SEPARATE TRUCK COLLECTION EQUIPMENT
AND MANPOWER SUMMARY
-MUNICIPAL PROGRAMS-
No.
Vehi-
Case Study Location cles
Bowie, Md.
Cincinati, Oh.
Dallas, Tex.
Fort Worth, Tex.
Great Neck, NYY.
Green Bay, Wise.
Greenbelt, Md.
Hemps tead, N.Y.
Marb lehe ad , Mas s .
Newton, Mass.
University Park, Tex.
West Hartford, Conn.
Average (compactor only)
1
1
6
9
2
1
2
5
1
1
6
2
1
1
4
2
Vehicle
Capacity*
(cu yd)
20
2*5- ton open
16
20
20
Dump truck
Jeep
16
16
l^s-ton open
20
16
16
10
23
20
18.6
Crew
Size
3
3
2
2
3
3
2
3
3
2
3
3
3
3
3
3
2.8
Material
Collected"*"
M
G
P
N
P
N
N
G,M,N
P
P
N
G,M,P
N
P
P
N
*Rear-loading compactor vehicle unless otherwise identi-
fied.
+Gi Glass
M: Metal
N: Newspaper only
P: Mixed paper
37
-------
TABLE 14
SEPARATE TRUCK COLLECTION EQUIPMENT
AND MANPOWER SUMMARY
-PRIVATE PARTY PROGRAMS-
Case Study Location
Bedford, Mass.
Briarcliff Manor, N.Y.
Res ton/ Va.
Tucson, Ariz.
Villa Park, 111.
Average
No.
Vehi- Vehicle Crew
cles Description Size
1
1
2
2
1
6
5
20
1 x -6 ' open
ton open
cu yd open
Standard van
3-
1/2 ton van
3
3
4
1
4
3.0
Material
Collected*
-------
compactors could not be spared for separate collection.
Conversely, private party locations used non-compactor
vehicles exclusively.
The relationship between the number of trucks used for sepa-
rate collections and the number used for mixed refuse col-
lections was examined at the municipally operated case study
locations. As depicted in Table 15, no conclusive relation-
ships could be identified due to the diversity of variables
between locations (e.g., collection frequency and pickup
point for recyclables as compared to mixed refuse). Based
on the case study relationships, however, a crude indication
of relative equipment assignment for regular versus separate
collection trucks shows approximate ratios of 5:1 for once
per week wastepaper collection to over 20:1 for once per
month collection although both higher and lower ratios were
computed.
All municipal case study locations provided curb service for
recyclable materials. Due to the small quantities of recy-
clable material (as compared to mixed waste), on-property
collection using the separate truck approach expectedly
would not be cost-effective. However, in spite of the curb
collection point and the use of compactor vehicles, separate
collection crews generally were too large. Crew sizes for
municipally operated separate collection operations remained
the same as those for mixed refuse collection crews; an
average of 2.8 per*-.truck. In view of the following condi-
tions generally observed during the case studies, crews in
excess of two on a rear-loading compactor are considered
excessive:
Separate collections were made from the curb.
. Where more than one category of recyclable material
was acceptable (i.e., glass, metal, paper), each
material type was independently collected (e.g.,
glass during the first week of the month, metal
during the second, etc.).
. Comparatively small quantities of recyclable mate-
rial (versus mixed waste) were collected at each
stop.
Containers for recyclable materials are classified
as "one way items" (i*e., storage containers were
not returned to the curb).
Participation rates were substantially less than 100
percent, thus travel time and distances between col-
lection points was in excess of normal collection.
39
-------
TABLE 15
RATIO OF MIXED TO SEPARATE COLLECTION TRUCKS
Ratio of Collection
Vehicles Mixed
Case Study Location
Bowie, Md.
Cincinnati, Oh.
Dallas, Tex.-
Ft. Worth, Tex.
Great Neck, N.Y.
Greenbelt, Md.
Kemps te ad, N.Y.
Marblehead, Mass.
Newton, Mass.
University Park, Tex.
West Hartford, Conn.
Collection
Mixed
Refuse
Curb
Curb- 35%
Property-65%
Curb
Curb
Property
Curb
Curb
Curb
Curb
Alley
Property
Point
Separated
Materials
Curb
Curb
Curb
Curb
Curb
Curb
Curb
Curb
Curb
Curb
Curb
Mixed
Refuse
Collection
Frequency
(collections/
wk)
2
1
2
2
3
3
2
2
1
2
1
Mixed Separate
Trucks* : Trucks
(By Separate
Collection Frequency)
1/wk
6:1
2:1
5:1
5:1
10:1
2:1
3:1
1/2 wk 1/mo
1.3:1
10:1
25:1
20:1
7:1
*On-line trucks only.
-------
None of the case study locations employed the economical one-
man operated side-loading vehicle for separate collections,
whereas the above conditions would appear to favor applica-
tion of this method.
With the exception of Tucson/ curb collection services were
similarly provided by private party collectors. Crew sizes
averaged 3 per vehicle, not unreasonable for open type vehi-
cles used in these locations. Use of non-compacting vehi-
cles required careful use of available space. Consequently,
paper was usually stacked and glass/metal often container-
ized in 55 gal drums placed on the truck bed to keep mate-
rials separate and facilitate offloading. Therefore, a
driver, loader, and stacker were justifiably used.
Time-motion studies10 performed in Fort Worth also pointed to
the excessive size of compactor crews used for separate col-
lection. Separately collected wastepaper in Fott Worth was
estimated to have a compacted density of about 650, Ibs/cu yd.
Based on limited weighings conducted during the household
study, the same density was achieved via simple bundling of
stacked newspaper. Whereas retention of bundled density on
an open truck requires labor for stacking, the compaction
mechanism should replace the need for the equivalent of
this stacking labor.
Separate Truck Program Performance*
Separate truck program performance can be measured in sev-
eral ways: participation achieved, waste quantities di-
verted, and collection productivity. Participation rates and
diverted disposal quantities appear to be related. Together
with collection productivity and revenues for collected
material, they largely determine the economic viability of a
separate collection program.
Prior to assessing performance, however, participation re-
quires definition. Only two case study locations had esti-
mates of the total amount of recyclable materials of various
types entering the solid waste stream. Consequently, re-
covery rates were not available in total or on a material by
material basis.* Thus, each location was requested to
*Program performances measured in this section are in-
fluenced by such interrelated factors as community
socio-economics and initial and on-going public rela-
tions. In fact, these factors may impact more on per-
formance criteria than the specific approach to separate
..collection (i.e., separate truck or rack).
*Separated materials as a percent of total waste dis-
posal were estimable, and will be discussed.
41
-------
provide an estimate of householder participation at the time
of the case study visit. Participation was defined as the
percent of householders in a separate collection area plac-
ing out recyclable materials on a given collection day. -
With few exceptions, the data or estimates provided 'by each
case study location consistent with this definition were
used throughout this report wherever participation rate is
discussed.*
Participation. Participation is a necessary ingredient for
program success. At the onset of the study, frequent sepa-
rate collections and/or mandatory separation were hypothe-
sized as necessary to maximize program participation. The
17 case studies contained a mix of mandatory and voluntary
programs, and had collection frequencies ranging from once
per week to once per month. Only Fort Worth operated a pro-
gram with two different collection frequencies under similar
conditions within the same city. In Fort Worth, the once
per week separate collection service achieved a 40 percent
participation rate, while the areas receiving service every
other week participated at only a 25 percent rate.
The Fort Worth results, taken independently, tend to support
a hypothesis that more frequent collection will increase
level of participation. In order to further test the hy-
pothesis. participation rates achieved by all wastepaper
programs* were plotted as a function of collection frequency
in Figure 4 Mandatory or voluntary program identification
JL iv™K°^ ' ^thou^h there *ay be some credance to
the hypothesis, participation must also be a function of
*Exceptions to this definition were when quantities re-
covered were noticeably out of proportion with partici-
pation estimates. in such cases, participation rates
were adjusted to reflect a more meaningful estimate?
Hempsjead' New Y°rk officials estimated
°Ut 8° Percent- The 80 percent esti-
'
-
S °n PartlciPation prior to increasing the
Y seParate collection. The 80 percent
estimate was not supported by the per capita newspaper
?heeoveran^^iStiCS-5r°Vided * Hempstead? Tallin
the overall data provided, a 42 percent participation
rate was estimated for the total collection area
ItL^f tnch-C°nS.traint WaS Pl-^d £ S2 test'in an
studv lor*^ S hom°9eneity in the results. In case
separaie?f ™?T ^T wastePaPer and glass/metal were
achieve^ a b?ii *', wastePaPer Programs generally
achieved a higher participation rate. Ease of waste-
6 was
42
-------
Co
c
o
•H
•P
(8
QJ
^•M
•H
u
•rl
-P
m
•P
C
0)
o
n
CM
100
rt f\
90
80
70
60
50
40
30
20
10
0
•N (Bowie)
•N (Great Neck)
•N (Briarcliff • N (West Hartford)
Manor)
•P (Bedford)
•P (Marblehead)
•N (Newton)
•N (Res ton) • P (Ft. Worth)
•N (Green Bay)
•P (Villa Park)
•
i • i i
One Two Three
LEGEND
• Voluntary Program
• Mandatory Program
N Newspaper Only
P Mixed Paper
• P (Greenbelt)
• N (Hempstead)
• P (Ft. Worth)
• P (University Park)
• N (Dallas)
• P (Cincinnati)
Four
(Weekly)
Monthly Collection Frequency
Figure 4: Participation rate as a function of separate collection frequency
-------
other variables such as community socio-economics and public
relations as discussed earlier. Several bi-weekly and
-monthly programs had greater participation rates,than did 'the
weekly programs; and mandatory rates were exceeded by volun-
tary rates in some locations. Also evidenced is the trend
of newspaper programs to exceed mixed paper programs in
achieving participation. Ease of newspaper separation is
believed to be the primary reason for this disparity.
By replotting participation rates in terms of the separate
collection program duration (Figure 5), a more positive
relationship is indicated. Figure 5 indicates an expected
increase in participation of about 18 percent annually based
on case study location conditions.
In general, a voluntary program is recommended at program
inception. By using voluntary participation as a barometer
of public acceptance, the effectiveness of a mandatory pro-
gram can be properly assessed. Great Neck, Hempstead, and
West Hartford each initiated separate newspaper collection
on a voluntary basis and adopted a mandatory ordinance after
the program was well received by the populace. Greenbelt,
following a successful voluntary program, was in the process
of making mixed paper separation mandatory at the time of
the case study. Villa Park and Marblehead may typify the
reaction to newly mandated paper separation ordinances. Al-
though these two programs can be expected to grow, they exem-
plify that an ordinance, by itself, does not guarantee
higher participation.
A change in pickup location for materials was also con-
sidered as possibly adversely affecting participation.
Three locations, Briarcliff Manor, Great Neck, and West
Hartford, provided on-property service for mixed refuse col-
lection while newspapers were required to be placed at the
curb by the householder for separate collection. However,
participation rates in these communities were among the
highest. The communities were relatively small (population
ranging from 7,500 to 70,000) and ranked among the highest
in socio-economic status; therefore, participation might be
expected to be high. Although only slightly lower on the
socio-economic scale, University Park (population 20,000)
achieved average participation rates even though residents
were required to place recyclable materials at the curb
rather than at the normal alley location for mixed refuse.
How a large municipality would be affected by a change in
pickup location is difficult to generalize although the ex-
perience of the above four communities is encouraging.
44
-------
u\
c
o
•H
-P
(0
•2*
O
-H
4J
rt
Oi
4J
c:
a)
0
0)
04
100
90
80
70
60
50
40
30
20
10
i
. Percent Participation = 11.5 + 1.5 (Program Duration)
. Coefficient of Correlation = 0.9
^^
• N (Great Neck)-^
^^^
-X^
•N (West Hartford)
• N (Briarcliff Manor)
•P (Greenbelt)
^xx^
• N ^(Hempstead)
^^X*^
• P (Marblehead)
•N (Newton/ University Park) •
^^X'* P (Ft. Worth) B
X^^ *N (Reston) N
•N (Green^N (Dallas) P
^^^ oscy )
m P (Villa Park) .
^X • P (Cincinnati)
-
04 8 12 16 20 24 28 32 36
^^•N (1
^
X^
Legend
Voluntary Program
Mandatory Program
Newspaper Only
Mixed Paper
40 44 48
(Bowie)
Separate Collection Program Duration (months)
Figure 5 • Participation rate as a function of program duration.
-------
Diverted Disposal Quantities. As previously noted, a desire
to reduce waste quantities disposed was stated as being a
primary motivation for activation of many of the studied
separate collection programs. The relationship between col-
lection frequency and program performance in terms of di-
verted disposal quantities was investigated.
Wastepaper collection frequency was related to waste quanti-
ties diverted from disposal. Although the average partici-
pation of weekly, bi-weekly, and monthly programs was virtu-
ally the same (see Table 16), weekly programs had an average
diverted disposal quantity of over 7 percent versus 6 per-
cent for bi-weekly programs and about 3 percent for monthly
programs. Thus, a positive relationship appears to exist:
diverted disposal quantities increased as collection fre-
quency increased.
This frequency/diverted disposal relationship was reinforced
by studies performed in the Fort Worth pilot areas.10 The
average participant in the weekly collection area placed out
21.0 Ibs of mixed paper for collection. Comparatively, bi-
weekly participants placed out 30.6 Ibs, or an average of
only 15.3 Ibs per week. Apparently householders are willing
to separate a larger portion of their recyclable wastes if
storage time is reduced, that is, if separated materials are
collected more frequently.
Diverted disposal quantities were not affected by mandatory/
voluntary program status in the case study communities. The
voluntary programs experienced an average diverted disposal
rate of 5.4 percent versus a rate of 6.6 percent for the
mandatory programs. The mandatory programs, however, were
strongly influenced by the Hempstead program. Excluding
Hempstead, the mandatory programs diverted 5.2 percent,
similar to the rate achieved by the voluntary programs.
Although these results may be biased by uncontrollable case
study idiosyncracies, this comparison seems to further de-
emphasize the importance of a separate collection mandate
for program success.
Table 17 compares program participation by type of recyclable
material and the quantity of material diverted from disposal.
As seen, the average participation rate in newspaper only
programs was 42 percent. Mixed paper programs averaged 32
percent participation while glass/metal programs had average
participation rates of 31 and 25 percent, respectively.
The newspaper programs diverted about 6 percent of the total
residential solid waste from disposal while mixed paper pro-
grams diverted almost 7 percent. One should not necessarily
conclude that mixed paper programs divert greater quantities
46
-------
TABLE 16
DIVERTED DISPOSAL AS A FUNCTION OF SEPARATE COLLECTION FREQUENCY
-WAS7EPAPER PRQGMMS-
Average quantities collected
Case study location*
Participation
rate
1%)
Total residential
refuse
(tons/mo)
Separated
paper
(tons/mo)
Disposal
reduction
(% by weight)
I/BIO Collection Frequency
Sowie, Kd.
Briarcliff Manor, N.Y.
Great Seek, N.V.
Green Bay, Wisc.+
Marblehead, Mass.
Newton, Mass.
Villa Park, 111.
Total/Average
1/2 vik Collection Frequency
Ft. Worth, Tex.*-*
West Hartford, Conn.
Total/Average
1/wk Collection Frequency
Bedford, Mass.
Cincinnati, Oh.**
Dallas, Tcx,+
Ft. Worth, Tex.*'*
Greenbelt, K&.
Hempstead, N.Y.
University Park, Tex.
Total/Average"1"*1
Combined Total/Average**
75
53
64
22
33
30
1_7
39
25
5_4
41
45
15
22
40
50
42
30_
39
39
1,560
280
480
260
1,040
4,300
970
8,890
2,020
3,810
5,830
31
22
28
7
46
121
35
290
131
220
351
56
167
145
154
32
813
100
1,300
1,941
2.0
7.9
5.8
2.7
4.4
2.8
3.6
3.3
6.5
5. S
6.0
10.0
1.6
6.3
11.6
7.3
7.2
5.2
7.4
•6.0
*Reston, Va., and Tucson, Ariz, not included due to absence of applicable data.
•fProgram in pilot area only.
ITwo pilot areas.
**Severe scavenger problem. Data accounts only for paper collected by municipality.
++Does not include Cincinnati due to scavenger problem.
-------
TABLE 17
PERFORMANCE PROFILES FOR SEPARATE TRUCK CASE STUDY LOCATIONS
00
Case study location*
Newspaper Only Programs
Bowie, Md.
Briarcliff Manor, N.Y.
Dallas/ Tex.fr
Great. Neck, N.Y.
Green Bay, Wise.*
Hemps te ad, N.Y.
Newton, Mass.
West Hartford, Conn.
Total/Average
Mixed Paper Programs
Ledford, Mass.
Cincinnati, Oh.+
Ft. Worth, Tex.*
Greenbelt, Md.
Marblehead, Mass.
University Park, Tex.
Villa Park, 111.
Total/Average**
Contained Total/
Average: Paper**
Participation
rate
<%)
75
53
22
64
27
42
30
54
42
42
15
25,40**
50
33
30
17
32
39
Average quantities
(tons/mo)
Total residential
refuse
1,560
280
2,300
480
260
11,370
4,300
3,810
24,460
560
10,580
3,100
440
1,040
1,930
970
8,040
32,400
collected
Separated
material
31
22
145
28
7
813
121
220
1,387
56
167
285
32
46
100
35
554
1,941
Disposal
reduction
(% by weight)
2.0
7.9
6.3
5.8
2.7
7.2
2.8
5.8
5.7
10.0
1.6
9.2
7.3
4.4
5.2
3.6
6.9
6.0
-------
TABLE 17 (Continued)
Case study location*
Average quantities collected
(tons/mo)
vo
Glass Programs
Bedford, Mass.
Bowie, Md.
Green Bay, Wise.
Marblehe adf Mas s.
Total/Average***
Metal Programs
Bedford, Mass.
Bowie, Md.
Green Bay, Wise.
Marblehe ad, Mas s.
***
Total/Average
Combined Total/Average
Participation
rate
All Programs
**,++
42
7
31
22
31
42
7
31
il
25
###
Total residential
refuse
Separated
material
,1,860
28
9
6
32
66
5
3
3
11
19
2,089
Disposal
reduction
(% by weight)
5.0
0.5
2.3
3.0
3.5
0.9
0.2
1.2
1.1
1.0
6.4
*Reston, Va. and Tucson, Ariz, not included due to absence of applicable data.
+Severe scavenger problem. Data accounts only for paper collected by
municipality.
tProgram in pilot area only.
f#Two pilot areas. 25% participation in bi-weekly areas; 40% participation
in weekly collection area.
**Does not include Cincinnati due to scavenger problem.
++Multiple material programs not double counted to derive totals/averages.
***Does not include Bowie for reasons discussed in text.
#ffAverage participation cannot be accurately determined due to unknown interface
of participants in multi-material programs.
-------
of waste at less participation than newspaper only programs
since six of the eight newspaper programs had collection
frequencies of once per month, while five of the seven mixed
paper programs received weekly service.
Glass and metal programs had disposal diversion rates of 2
and 0.6 percent, respectively. Without the Bowie program,
the diversion rates increased to an average of 3.5 percent
for glass and 1 percent for metal. The Bowie glass and
metal diversion rates are discounted because:
. Bowie achieved notariety by pioneering legislative
efforts to outlaw non-returnable beverage con-
tainers. While the constitutionality of the ordin-
ance was being tested, the glass and metal container
separate collection program was initiated.
. The Bowie newspaper program achieved a reported par-
ticipation rate of about 75 percent with once per
month collection, while the glass/metal program re-
ceived only 7 percent participation with weekly col-
lection.
It is believed the general populace may have curtailed pur-
chasing non-returnable containers because of the legislative
effort - thus quantities of glass and metal would be low.
The participation rates are questionable because of their
variance with experiences of other locations.
An interesting relationship which may have socio-economic
implications was provided by the Green Bay, Wisconsin case
study. The Green Bay program required participants to
accumulate separated materials for a month: metal was col-
lected during the first full week of the month, glass during
the second, and newspaper during the third week.* In that
collection frequency is equivalent for each material,
equivalent participation or a higher rate for newspaper due
to ease of separation, might be anticipated. However, par-
ticipation in the glass/metal portions of the separate col-
lection program was reportedly 31 percent versus 22 percent
in the newspaper portion. Forty percent of the residents in
the Green Bay pilot area were identified as lower-middle
class and transient. The number of regular subscribers to
a newspaper could be lower for this group.
*Marblehead, Massachusetts, had a similar separate col-
lection scheme: mixed paper during the first week,
metal during the second, clear glass during the third,
and green glass during the fourth.
50
-------
Aside from Bowie, the three multi-material programs - Bed-
ford, Green Bay, and Marblehead - had an average diverted
disposal rate of about 10 percent, significantly higher
than wastepaper only programs were able to achieve. The
average/ however, is on the prorated average of three spora-
dic test programs conducted in Bedford whereupon almost 16
percent of the total residential solid waste generated was
diverted. Thus, the 8 percent diversion rate in Green Bay
and Marblehead may be more typical.
Collection Productivity. Collection productivity in the
separate collection area was expressed in tons of recyclable
material per separate collection truck per day. The produc-
tivity factors are summarized with respect to the wastepaper
programs in Table 18. As shown, collection productivity
averaged between five and six tons per truck per day regard-
less of collection frequency.
The productivity comparisons of glass and metal operations
were limited to Bowie, Green Bay, and Marblehead. Bowie
collected glass and metal weekly while the other two loca-
tions provided once per month service with productivity fac-
tors summarized in Table 19. Compared to the wastepaper pro-
grams/ productivity of glass and metal programs is fairly
poor. However, this is due to comparatively low participa-
tion in conjunction with relatively low generation rates for
glass and metal in residential refuse.
Separate Truck Program Economics
The cost of a separate truck collection program and/or its
impact on mixed refuse collection operations varies with a
number of factors. Costs were assessed via two approaches:
Fully allocated cost approach: separate collection
costs are evaluated independently of mixed refuse
collection and disposal costs. Costs were allocated
for labor, equipment, etc., whether or not actually
incurred.
Incremental cost approach: incremental costs and/or
savings accruing to a municipality when the overall
costs of solid waste management are compared before
and after implementation of a separate collection
program. Costs included were only those actually
incurred (i.e., if surplus trucks and/or labor were
used, no out-of-pocket costs were incurred).
Fully Allocated Cost Approach. This approach assigns sepa-
rate collection costs on an apportionment basis. For example.
51
-------
U1
to
TABLE 18
SEPARATE TRUCK PRODUCTIVITY FACTORS
-WASTEPAPER PROGRAMS-
Separate Collection Trucks
Case Study Location
1/mo Sep. coll'n frequency
Briarcliff Manor, N.Y.
Great Neck, N.Y.
Green Bay, Wise.
Marblehead, Mass.
Newton, Mass.
Aver age *,+
1/2 wk Sep. coll'n frequency
Ft. Worth, Tex.
West Hartford, Conn.
Average*
1/wk Sep. coll'n frequency
Cincinnati , Oh . &
Dallas, Tex.
Ft. Worth, Tex.
Greenbelt, Md.
Hemps tead, N.Y.
University Park, Tex.
Average*, **
No.
1
2
5
2
1
1
2
6
9
1
1
6
5
Truck- days/mo .
2
6
22
10
20
22
44
130
39
22
9
130
22
Wastepaper
Collected/mo
(tons)
22
28
7
46
121
131
220
167
145
154
32
813
100
Ave . Tons
Collected/
Truck/day
11.0
4.7
0.3
4.6
6.0
"577
6.0
5.0
5.3
1.3
3.7
7.0
3.6
6.2
4.5
576
*Weighted by truck days per month.
+Does not include Green Bay due to extreme system idiosyncracies.
tSevere scavenger problem. Data accounts only for paper collected by
municipality.
**Does not include Cincinnati due to scavenger problem.
-------
in
TABLE 19
SEPARATE TRUCK PRODUCTIVITY FACTORS
-GLASS AND METAL PROGRAMS-
Material/Case
Study Location
Glass
Bowie, Md.
Green Bay, Wise.
Marblehead, Mass .
Average*
Metal
Bowie, Md.
Green Bay, Wise.
Marb lehead , Mass .
Average*
Separate
NO.
2
5
2
2
5
2
Collection Trucks
Truck- Days/Mo
4
22
20
4
22
10
Material
Collected/Mo
(tons)
9
6
32
3
3
11
Average Tons
Co 1 le c te d/T r uck /
Day
2.2
0.3
1.6
1.7
0.8
0.1
1.1
1.0
*Weighted by truck-days/per month.
extreme system idiosyncracies.
Does not include Green Bay due to
-------
truck depreciation costs are assigned only for the portion
of time that the truck is actually used for separate collec-
tion activity. Labor costs (including fringe benefits),
truck operating costs {fuel, oil, tire repair and replace-
mentr and maintenance parts and repair), and overhead expen-
ses (administration, supervision, and facility costs) are
similarly allocated. In this manner, costs are attributed
on the basis of actual equipment and labor utilization
whether one crew is required for a few hours per month or
several are required on a daily basis.
Fully Allocated Separate Collection Costs. Figure 6 presents
a Profile o± the separate truck case study locations depict-
ing type of material separately collected, frequency of col-
lection, the estimated fully allocated cost of the separate
collection subsystem expressed on a per ton of material
separately collected basis*, and relative size of the pro-
gram based on the number of separate collection man-hours
expended per month. Revenues from collected materials and
saving in disposal costs are not included.
The plotted data reveal no apparent relationship between
??™raiU Si26 and the °°st to Perfo™ separate truck collec-
tt™?' Th^e ar?' however, other relationships worth men-
tioning. The collection cost variations between glass,
metal, and paper are quite significant. Glass an! metal
heal ^JS^TiZ C0llected in »™^> Green Bay, and Marble-
dentlal -f,?9 h .the ^portion of glass and aetal in resi-
tiSn SiaJ 1S ?lrnilar on a wei9ht basis, glass collec-
n^° <-™StS Were substantially lower, ranging from $76 to $81
$202 pei to????! tO metal Collection <*»ta of $115 to
the
o
glasses, is almost entirely comprised of one-way food and
srsas^^^K^^
3?r£ri;™
gory as are glass containers in the "glass category,"
col^ction program independently col-
^JS ^e type of recyclable LterialT appli
costs were assigned to the collection activities
54
-------
Based on the household study, the ratio of recyclable glass
generated per household per week (4.5 Ibs) to that of metal
(2.0 Ibs) was 2.25 to 1. Although the study households were
probably more conscientious in their separation efforts,
similar ratios were evident in the glass/metal quantities
collected at most of the case study locations:
Quantities Collected
_ (tons/mo) Ratio
Case Study Location _ Glass Metal _ Glass/Metal
Bedford, Mass. 28 5 5.6:1
Bowie, Md. 9 3 3.0:1
Green Bay, Wis. 6 3 2.0:1
Marblehead, Mass, 22_ 11 2.9:1
Total/Average 75 22 3.4:1
In addition to glass components being readily separated by
householder s, a glass container weighs several times that of
a metal container, thereby increasing weight placed for col-
lection. The increased weight helped to lower unit costs of
glass collection as compared to metal.
locations simultaneously collected more than one type of
recyclable material - Bedford collected glass, metal, and
roixed paper, and Tucson collected newspaper and metal at the
same time. As shown in Figure 6, Bedford's collection cost
was under $25 per ton and Tucson had a cost of about $32 per
ton. in Bedford and Tucson, however, paper accounted for 50
and 80 percent of the total weight collected, respectively.
The main drawback to large scale, simultaneous collection is
the requirement to use an open truck and allocate space for
each material.* In the case of Bedford, vehicle storage
sPace allocated for paper always filled prior to the glass
and metal storage space. This occurrence necessitated
transfer trips to offload paper.
With two notable exceptions, independent wastepaper collec-
tion programs (newspaper only or mixed paper) had fully allo-
cated separate collection costs below $40 per ton. Cincinnati
had fully allocated collection costs of about $102 per ton.
"Compactors are not presently compartmentalized. Maxon
Industries, Inc., however, has designed a compartment-
alized compactor. A 3 cu yd non-compacting compartment
will soon be available to isolate recyclable materials
from compacted -mixed refuse.
56
-------
^
C
0
(IJ
a
w
M
m
•H
o
•a
^
-------
As previously discussed, Cincinnati had a severe scavenger
problem; thus collection productivity was reduced and costs
increased. The Green Bay separate collection program was
implemented by modifying an existing separate collection
program. The existing program consisted of one truck used
to collect combustibles and one for non-combustibles. The
available non-combustible truck was reassigned to collect
different recyclable materials on successive weeks in a
pilot area. Although the system was relatively easy to im-
plement, the collection capacity was too large to effectively
collect the small quantities of recyclable material volun-
tarily separated in the pilot area. The high costs of the
Green Bay operation reflect this condition.
The two programs with the lowest collection costs, Briar-
cliff Manor and Villa Park were both privately operated.
In each location, an independent truck owner collected
separated materials in exchange for the revenue received
from material sales.* In Briarcliff Manor only newspapers
were collected, while mixed paper was collected in Villa
Park. Both programs were "one truck operations" whereby
the driver and owner were one and the same and part-time
labor was hired on an "as needed" basis. Thus, administra-
tive and overhead costs for each program were negligible.
This fact was reflected in the estimated fully allocated
collection cost - $8 per ton at Briarcliff Manor and about
$6 per ton at Villa Park.
Refuse collection operations are generally labor intensive
and separate collection is no exception. Thus, labor costs
are an important element in the overall cost of a separate
collection program. In 1972 (latest data available), the
U.S. Department of Labor tabulated the average first year
salaries (exclusive of fringe benefits) of municipal refuse
collectors in cities of 100.000 or more inhabitants on a
regional basis as follows:^
*Although not case study locations, the California cities
of Fullerton and San niego implemented private party
programs whereby paperstock dealers provide respective
separate collection services and pay the city for the
"privilege" of making the separate collections. Pul-
lerton is paid $5/tcn for the first 100 tons of news-
paper collected per month and $7/ton thereafter. A
similar arrangement was agreed upon in San Diego. The
city receives $5/ton for the first 500 tons/mo and $10/
ton thereafter.
57
-------
Average Annual
Region Salary per Collector
Northeast $9,390
South 5,510
North-Central 8,700
West 7,780
Comparing the regional wage scales to the municipally oper-
ated programs in Figure 6 reveals a significant relationship.
The three Texas programs (southern region) had the lowest
collection costs while the northeast programs had the highest,
Thus, at least a portion of the cost disparity between pro-
grams can likely be explained by regional labor cost dif-
ferentials.
Effective Fully Allocated Separate Collection Costs. Sepa-
rate collection costs are reduced by deducting revenue re-
ceived for separated materials and diverted disposal sav-
ings.* Results are presented in Tables 20 and 21. Table 20
focuses on wastepaper programs only. Table 21 presents the
data for glass, metal and multi-material programs (i.e., pro-
grams that separately collected more than one type of recy-
clable material).
As shown in Table 20, the impact of increased wastepaper
revenues has had a significant impact on the program costs
determined at the time of the case studies. April 1973
revenues and diverted disposal savings were insufficient to
offset fully allocated separate collection costs in all muni-
cipal programs. The average loss was estimated to be almost
$13 per ton of wastepaper collected. Confronted with this
dismal financial picture, municipal separate collection pro-
gram managers were generally unconcerned.* Most felt that
the separate collection programs provided non-economic con*
tributions which compensated for the "loss" as determined by
the fully allocated cost method. Generally, the responses .-
re11 into three categories:
. Savings in landfill space and reduced incinerator
loadings were worth the cost.
. Equipment and crews are better utilized.
Citizens feel involved.
*The methodology used to estimate diverted disposal sav-
ings is delineated in Appendix B.
*A copy of each case study was sent to the respective
program managers for review and comment.
58
-------
TABLE 20
EFFECTIVE FULLY ALLOCATED COSTS FOR SEPARATE TRUCK OPERATIONS
-WASTEPAPER PROGRAMS-
NO
Case study location
Fully allocated
separate
collection cost
(S/ton)
Effective separate collection cost ($/ton)
Recyclable market at the
time of case study
(April 1973}
Current recyclable market
(March L974)
Revenue and
diverted dis-
posal savings
Net program
savings (cost)
Revenue and
diverted dis-
posal savings
Net program
savings (cost)
Municipal Programs
Cincinnati, Oh.*
Dallas, Tex.
Ft. Worth, Tex.
Great Neck, N.Y.
Green Bay, Wise.
Greenbelt, Md.
Hemps tead, N.Y.
Marblehead, Mass.
Newton, Mass,
University Park, Tex.
West Hartford, Conn.
102,40
11.20
17.40
29 . 70
63.50
34.40
31.40
27.50
25.40
12.00
38.80
25,20
8.30
10.10
15.70
18.80
8.80
18.00
6.40
14.00
8.70
17.40
(77.20)
( 2.90)
( 7.30)
(14.00)
(44.70)
(25.60)
(13.40)
(21.10)
(11.40)
{ 3.30)
(21.40)
76.50
43. 30
35.90
19.00
38.80
22. &0
32.00
33.40
33.50
43.70
47.80
(25.90)
32.10
18.50
(10.70)
(24.70)
(11,60)
0,60
5.90
8.10
31.10
9.00
Average Municipal"1"
Private Party Programs^
(12.70)
•Severe scavenger problem distorts program costs.
^Average does not include Cincinnati, Ohio.
^Bedford, Massachusetts and Tucson, Arizona collect wastepaper simultaneously with other
recyclable materials; therefore not included with wastepaper only programs.
**Program abandoned.
8.20
Briarcliff Manor, N.Y.
Reston, Va.
Villa Park, 111.
Average Private
8.00
22.20.
6.20
20.50
5.80
10.60
12.50
(16.40)
4.40
negligible
38.50
**
38.60
30.50
**
32.40
31.70
-------
TABLE 21
EFFECTIVE FULLY ALLOCATED COSTS FOR SEPARATE TRUCK OPERATIONS
-GLASS, METAL, MULTI-MATERIAL* PROGRAMS-
Case study location
Fully allocated
separate
collection cost
(5/ton)
Effective separate collection cost (S/ton)
Recyclable market at the
time of case study
(April 1973)
Current recyclable marfcet
(March 1974)
Revenue and
diverted dis-
posal savings
Net program
savings (cost)
Revenue and
diverted dis-
posal savings
Net program
savings (cost)
CV
o
Glass Programs
Municipal Programs
Bowie, Md.
Green Bay, Wise.
Marblehead, Mass.
Average
Metal Programs
Municipal Programs
Bowie, Md.
Green Bay, Wise.
Marbiehead,. Mass.
Average
Multi-Material Programs*
Municipal Programs
Bowie, Kd.
Green Bay, Wise.
Marbiehead, Mass.
Average
Private Party Programs
Bedford, Mass.
Tucson, Ariz.
Average
76.60
80.50
79.00
202.10
139.10
114.90
108.00
85.00
56.80
23.50
32.70
22.00
28.80
11.40
12.00
8.80
11.40
18.70
17.00
8.90
12.90
7.30+
( 54.60)
( 51.70)
( 67.60)
( 57.40)
(190.10)
(125.30)
(103.50)
(122.60)
( 89.30)
( 68.00)
{ 47.90)
( 55.40)
(10.60)
(25.40)
(14.00)
No change
No change
18.70
22.00
22.80
22.90
32.00+
(89.30)
(63.00)
(34.00)
(43.60)
(0.60)
(0.70)
(0.60)
•Programs that separately collected more than one type of recyclable material.
"Multi-material programs" collected different recyclable materials during
successive weeks of the month (Green Bay and Marbiehead) ; with different
trucks on the same collection day (Bowie); or simultaneously with one truck
(Bedford and Tucson) .
+Does not include revenue from a S12 per year fee paid by householders for
private separate collection service.
I Reproduced from
\oes\ ava\\ab\e copy.
-------
Applying the March 1974 wastepaper revenue rates to the case
study locations resulted in seven of the eleven municipali-
ties showing a net profit for separate paper collection aver-
aging about $8 per ton over all municipal programs (Table 20},
The private party paper programs fared better under depressed
market prices. Two of the three private wastepaper programs
had net gains although the overall private party average in
April 1973 was about even. The one "losing program/' Reston,
folded prior to the March 1974 assessment. The two success-
ful programs were more profitable as of March 1974, thus
having an average net profit of about $32 per ton.
Glass and metal programs did not share the same degree of
success experienced by wastepaper programs (see Table 21}.
There were no significant changes in glass and metal revenue
rates between April 1973 and March 1974. Glass programs had
average deficits of about $57/ton while the average metal_
program lost almost $123/ton. The relatively small quanti-
ties of glass or metal were not economically feasible for
independent collection when the fully allocated cost approach
is used.
The municipal multi-material programs shown in Table 21 rep-
resent a compilation of the costs of independently collect-
ing the various types of materials. Each of the private
parties simultaneously collected more than one material.
With the exception of Bowie which collected glass and metal
only, the multi-material programs benefited from the waste-
paper price rise. Although operating at a significant Defi-
cit under the fully allocated cost approach, the municipal
multi-material programs decreased the margin of loss from
$55 to $44 per ton when March 1974 wastepaper prices were
considered.
The private party multi-material programs rose from and aver-
age deficit of $14 per ton to a marginal loss or less than
one dollar per ton.
Incremental Cost Approach, This approach assigns costs to
the separate collection program only if the costs are incre
mental to costs budgeted for solid waste management. I« De-
termining whether a cost should be assigned under this ap-
proach^ the user himself asks "will this cost ^reflected
as an increase in the budget for the next operating Period?
If the answer is affirmative, the cost is assigned, other-
wise it is ignored.
Thus, the incremental cost approach does not assign depreci-
atioA costs of available equipment to separate collection
activities as it is not in excess of the established solid
61
-------
waste management budget. Similarly if trucks normally used
for such functions as bulky collection (Bowie) or bursh col-
lection (Dallas and University Park) were diverted for sepa-
rate collection without adversely affecting the primary ser-
vice, no incremental costs were attributed. However, the
incremental operating costs for fuel, oil, tire/battery wear,
and maintenance/repair due to the truck being activated or
reassigned to separate collection would be incurred and are
included. Additionally, if reserve labor was used for sepa-
rate collection, there were no additional costs incurred in
the solid waste management budget; thus no costs assigned.
However, part-time hires, such as required in Marblehead and
Newton would be incremental costs incurred by a separate
collection program.
For the purposes of this analysis, equipment and labor di-
verted from municipal public works functions other than
solid waste management were treated as incremental costs
(e.g., highway department labor was used for separate collec-
tion in Great Neck)* and assigned. Overhead expenses for
administration, supervision and facility requirements were
unaltered although some additional record keeping was nor-
mally required.
Due to data limitations, analyses of overall collection and
disposal costs before and after implementation of separate
truck collection programs were possible at only 13 of the 17
case study locations as listed in Table 22. At the time of
the case studies, 6 of the 13 programs had achieved a net
reduction in collection and disposal costs due to separate
collection and two others broke even. In terms of percent
change due to separate collection activities, the net costs
ranged from a reduction of about 5 percent to an increase of
7.5 percent, with an average increase of less than one per-
cent for the 13 programs.
Substituting the respective March 1974 market values for
separately collected materials into the case study analyses
resulted in all but one of the 13 programs achieving a net
reduction in residential solid waste management cost. Effec-
tive costs ranged from a decrease of 23 percent to an in-
crease of one percent with an average decrease of about 7
percent. This significant reduction was entirely due to
wastepaper price increases.
*Case study locations using equipment and/or labor di-
verted from other public works functions were unable to
quantify any adverse affect on the contributing func-
tions. .The incremental cost assumption was used as a
proxy.
62
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TABLE 22
IMPACT OF SEPARATE COLLECTION ON' OVERALL
RESIDENTIAL SOLID WASTE MANAGEMENT COSTS
-SEPARATE TRL'CK APPROACK-
Case study location
Collection and disposal
cost prior to implementation
of separate collection
(?/ton)
Material
separately
collected*
Collection ami disposal cost after implementation of
separate collection*
-------
Comparing the results of the incremental cost approach
(Table 22} to those of the fully allocated cost approach
(Tables 20 and 21} reveals some major differences. For
example, fully allocated costs allocated to the Green Bay
glass, metal, and newspaper program were quite high (about
$81/ton for glass; $139/ton for metal; and $63/ton for news-
paper) . All amounts were in excess of revenue received and
diverted disposal savings. However, using the incremental
cost approach, this program achieved a 2 percent savings in
the overall cost of solid waste management at the time of
the case study. This increased to 3 percent when March 1974
revenue prices were considered.
Another example is provided by the Cincinnati program. Even
though the scavenger problem decreased the effect of sepa-
rate collection on overall solid waste management costs,
Cincinnati was able to break even at the time of the case
study and achieve a two percent reduction in overall costs
when March 1974 revenues were considered.* This is an
entirely different result when depicted by the fully allo-
cated cost approach which estimated the loss in the Cincin-
nati program to be about $26 per ton of wastepaper collected.
Arguments of validity can be made for either the fully allo-
cated or incremental cost approach, and the ultimate deci-
sion as to which approach is to be used must lie with the user.
The incremental cost approach was used by most case study
municipalities in assessing the viability of their separate
collection programs. As currently practiced, separate col-
lection costs were generally absorbed within solid waste
management budgets. However, as separate collection pro-
grams grow, the capability of a budget to absorb costs may
be constrained by undue infringement on activities from
which equipment and manpower has been borrowed. When, and
if, this situation occurs, incremental resources will be
required and incremental costs become fully allocated to
separate collection.
Model Economics for the Separate Truck Approach
The case study costs are indicative of the economic via-
bility of the case study programs as practiced. As pre-
viously noted, however, crew sizes were often excessive for
collecting small quantities of separated materials. Also,
*Cincinnati was receiving the highest wastepaer revenue
of all programs at the time of the case study and in
March 1974: $14.20/ton and $56.50/ton, respectively.
64
-------
case study locations had not re-routed mixed refuse collec-
tion vehicles to compensate for the reduced waste quantities
diverted from disposal.
A refuse collection model13 was adapted and exercised to
evaluate further the economics of separate collection and
its potential impact on overall collection costs. The re-
sulting model evaluates costs of the separate collection
subsystem, the impact of separate collection of mixed refuse
collection (i.e., cost savings achieved via re-routing), and
accounts for diverted disposal costs and revenue generated
from sale of separately collected materials.
The model is fully described in Appendix C and was used to
assess costs under the varying conditions shown in Table 23.
Although the conditions and variables tabulated will likely
not fit the exact conditions of any given municipality, the
cost implications of a proposed separate truck subsystem may
be assessed by plotting and/or reviewing appropriate "bracket-
ing values" from the computerized printout accompanying this
report and the examples developed in Appendix D. The
accompanying tabulations account for variations in truck
capacity; crew size; collection frequency; mixed refuse haul
distance; the estimated collection cost prior to implementing
a separate collection subsystem; and the effective cost of
collection after implementation of the separate collection
subsystem considering both revenue and diverted disposal
savings.
If the conditions in a municipality are significantly dif-
ferent from those summarized in Table 23, the model may be
used to obtain applicable results by inserting local vari-
ables and/or conditions. For example, only curb pickup of
mixed refuse and separated newspaper was evaluated. Munici-
palities providing on-property service for mixed refuse
should insert applicable information and exercise the model
rather than attempt use of the tabulated data. Similarly,
municipalities that estimate the average weight of newspaper
Per household to significantly exceed the 7 Ibs per week
used in the model would again be advised to exercise the
model using applicable local conditions. The model is not
extremely complex although time should be taken to obtain
applicable data if the model is to be used. As a predictive
tool, the model results will be as good as the input data.
65
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TABLE 23
CONDITIONS ANALYZED VIA THE
ADAPTED REFUSE COLLECTION MODEL
Variable
Mixed
Collection
Separate
Newspaper
Collection
Crew Size (no./
vehicle)
Collection frequency
Collection location
Vehicle capacity
(cu yd)
Generation rate (Ibs/
household/wk)
Labor cost
Haul distance
Disposal savings
Revenue ($/ton)
Percent participation
1-Side loader
21
3JRear loader
1/wk, 2/wk
curb
16,20,25 rear
loader
20,25 side loader
61*-l/wk coll'n
79+-2/wk coll'n
National average*
$5.80-driver
$4.70-loader
Short haul, long
haul
1-Side loader
2V
-jiRear loader
1/wk, l/2wk, 1/mo
curb
12,16,20,25 rear
loader
20,25 side loader
7 (newspaper only)
National average1
$5.80-driver
$4.70-loader
Short haul
Landfill and in-
cineration (first
and second party
costs)
8,25
20,50,80
*Based on 2.5 Ibs per person per day and 3.5 persons per
+household.
Based on research by Quon, generation rate increases
»with collection frequency.1*
"Includes 25 percent fringe benefits.
66
-------
Although being too extensive to delineate each of the more
than 1,200 combinations resulting from the variables listed
in Table 23, the printout accompanying the report can be
used as a tool to provide insight to the potential impact
of separate collection on overall solid waste collection
costs. In order to exemplify the use and value of the
model output, six collection situations were selected for
inclusion in the report:
Mixed
Crew Size Compactor Collection
(no./vehicle) Vehicle Frequency
Situation
No.
1
2
3
4
5
6
Mixed
3
3
1
3
3
1
Separate
3
2
1
3
2
1
Type
(loading
location)
Rear
Rear
Side
Rear
Rear
Side
Size
(cu.yd.)
20
20
20
20
20
20
(no./wk.)
1
1
1
2
2
2
The first and fourth situations were selected to typify the
"average" municipal case study. These parameters included
use of three man crews for both mixed and separate collec-
tion from the curb with 20 cu yd rear-loading compactors.
Aside from changing mixed collection frequency, the only
Codification in the parameters of the second and fourth
situations was reduction of separate collection crew size
from three to two. The third and sixth situations repre-
sent minimization of crew size for both mixed and separate
collection. For the purpose of illustration, mixed refuse
collection frequency was fixed at either once or twice per
week, while separate collection frequency was varied.
Results are shown in Figures 7 through 12. The dual set
curves for each collection frequency represent differences
due to long and short haul situations.* The tandem curves
shown for long and short haul situations represent the
difference in economic feasibility resulting from a change
in revenue from an average of $8/ton to an updated market
*Long and short haul situations were depicted in the model
calculations by assuming respective one-way haul times
of 15 min. and 45 min.
67
-------
cri
oo
ui
i
l/wk Separate
Collection
Frequency
Paper market at time of case studies
(April 1973): $ 8/ton
Assumed paper market: $25/ton
i
i
i
Diverted incinerator Costs
Diverted Landfill Costs
1/2 wk Separate
Collection
Frequency
i
i
i
i
20 cu yd
3/3
I /wk
Combined Collection Cost for Long Haul-\
Combined Collection Cost for Short Haul —s
2.
I/mo Separate
Collection
Frequency
i
_L
i
J
10 20 30 40 SO 60 70 00 90 100
10 20 30 40 50 CO 70 80 90 100
10 20 30 40 SO CO 70 80 90 100
PERCENT PARTICIPATION
Figure 7 . Impact of optimizing refuse collection operations: exemplary analysis,
3 man mixed refuse collection performed once per week, 3 man spparate collection crew.
-------
vo
O
29
24
23
22
21
20
O
o '•
o
- - 18
O M
•«
u O 15
S ,4
o
o
c o
10
«
•*~
«t-
tl)
Diverted Incinerator Costs
Diverted Landfill Costs
_L
Paper market at time of case studies
(April 1973 ): $8/ton.
Assumed paper market $25/ton
l/wk Separate
Collection
Frequency
t
I
"Combined Collection Cost for Short HculO
1/2 wk Separate
Collection
Frequency
I
20 cu yd
3/2
l/wk
Combined Collection Cost for Long Haul'-)
t~-r,_... ^*
I/mo Separate
Collection
Frequency
i
0 10 20 30 40 SO 60 70 CO 90 100 0 10 20 30 40 SO $0 70 BO 90 100 0 10 20 SO 40 50 «O 70 SO 9O 100
PERCENT PARTICIPATION
Figure 8_- Impact of optimizing refuse collection operations: exemplary analysis,
3 man mixed refuse collection performed once per,week, 2 man separate collection crew.
-------
f>
ui 2
O
= »
O
§ •'
~ ~ I
fc.
o «
§ 8 '«
a OT
o
<• 5
o <
o •» is
c o
Paper market at time of case studies
(April 1973): $8/ton.
Assumed paper market $25/ ton
l/wk Separate
Collection
Frequency
1/2 wk Separate
Collection
Frequency
Diverted incinerator Costs
Diverted Landfill Costs
Combined Col lection Cost for Short Houl~j
20 cu yd
I/I
I wk
I/mo Separate
Collection
Frequency
Combined Collaction Cost for Long
10 20 50 40 SO CO 70 90 90 100
10 20 SO 40 SO CO 7O SO 90 100
10 20 50 40 90 60 70 40 90 100
PERCENT PARTICIPATION
Figure 9^ . Impact of optimizing refuse collection operations: exemplary analysis,
1 man mixed refuse collection performed once per week, 1 man separate collection crew.
-------
40
39
38
^ f
10 2O 3O 40 SO CO TO BO 90 100
0 IO 20 30 40 SO CO 70 80 9O 100
PERCENT PARTICIPATION
10 20 50 40 SO CO TO BO 9O IOO
Figure ,10« Impact of optimizing refuse collection operations: exemplary analysis,
3 man mixed refuse collection performed twice per week, 3 man separate collection crew.
-------
in 3
O
X 3
O
§ 3
2"3
o 2
C O 3
00*
«- O 30
O)
Q- to
T5 *
S *>
«
"5
Diverted Incinerator Costs
Diverted Landfill Costs
l/wk Separate
Collection
Frequency
1/2/wk Separate
Collection
Frequency
r
20 cu yd
3/3
2/wk
Combined Collection
Cost for LongHauio
I/mo Separate
Collection
Frequency
Combined Collection
Cost for Snort Haul-j
*- 23
UJ
22
21
Paper market at time of co$e studies
(April 1973): $ 8/fon.
Assumed paper market: $25/ton
:
i
i
IO 20 30 40 SO 60 70 80 >0 100 0 10 20 SO 4O 90 60 7O 6O 90 100
10 2O 30 40 90 60 70 80 90 100
PERCENT PARTICIPATION
Figure 11« Impact of optimizing refuse collection operations: exemplary analysis,
3 man mixed refuse collection performed twice per week, 2 man separate collection crew.
-------
30
20
«t
2 27
O
I 26
O
1 2S
O
24
O
O
sVa
-
< 22
s»
O 19
5 IB
e o
O =E t?
U —.
= '«
O
0 ,
Paper market at time of case studies
(April 1973): $ 8/lon.
Assumed paper market: $25/ton
l/wk Separate
Collection
Frequency
Diverted Incinerator Costs
Diverted Landfill Costs
1/2 /wk Separate
Collection
Frequency
I l_
20 cu yd
I/I
2/wk
Combined Collection Cost for Long
I/mo Separate
Collection
Frequency
Combined Collection Cost for Short Haul
j L
10 2O 50 4O 50 *0 70 $0 90 100
10 20 10 40 SO SO 70 80 9O 100
PERCENT PARTICIPATION
IO 20 M> 40 90 60 TO 80 9O 100
Figure
1 man
L2. Impact of optimizing refuse collection operations: exemplary analysis,
mixed refuse collection performed twice per week, 1 man separate collection crew.
-------
price of $25/ton. The respective bands at each revenue rate
represent the difference in diverted disposal cost savings
between a city operating its own landfill to a city using
a non-owned incinerator.
Separate collection is seen to have a more immediate impact
in long-haul situations due to reductions in long-haul of
mixed refuse. Similarly, savings attributed to quantities
diverted from incineration have a higher payoff than quan-
tities diverted from a landfill. Another logical consis-
tency is that once per month separate collection in con-
junction with mixed collection represents the least cost
combination.
The variation in curve shape is due to the effect that
revenue and disposal savings have on total collection costs
at various separate collection frequencies. In essence,
revenue and disposal savings have a dampening effect on
overall collection costs. In certain instances these sav-
ings are not sufficient to dampen overall costs to a point
where an effective cost decline results. Cost is the most
sensitive to collection frequency and labor, and least
sensitive to truck capacity (based on an assessment of all
capacities listed in Table 23).
The importance of reducing separate collection crew size at
the once per week separate collection frequency is shown
by comparing Figures 7 and 8, or 10 and 11. Using the
combined refuse collection cost (designated on the Figures)
as a baseline situation, reduction of separate collection
crew size from 3 to 2 results in a breakeven situation oc-
curring with about 30 to 40 percent less participation at
the 1/wk separate collection frequency. Reducing crew size
at the l/2wk and 1/mo separate collection frequencies re-
sulted in breakeven situations occurring with 5 to- 10 per-
cent less participation. This apparent decline in impact is
due to the relationship between quantity of newspaper per
stop and crew size (i.e. at once per week, a crew collects
7 Ibs per stop; at biweekly or monthly frequencies, the crew
would respectively collect 14 or 30 Ibs, inherently result-
ing in greater efficiency). Thus, economics of scale are
evident.
The situations hypothesizing one man collection situations
depict the least cost solutions for residential solid waste
collection prior to and after separate collection imple-
mentation. The effect of lessening costs in almost every
situation depicted in Figures 9 and 12 results from news-
paper revenue and diverted disposal savings being able to
overcome equipment and one-man labor costs at a faster rate
74
-------
than if two or three times the labor is used to collect
identical quantities of waste (mixed or separate) when larger
crews are used.
Regardless, the six illustrations typify the value of using
the model in local decision making. Without a costly trial
and error procedure, various service levels can easily be
hypothesized, breakeven situations assessed, and savings
and/or costs estimated.
75
-------
VI
SEPARATE COLLECTION: RACK APPROACH
The most appealing aspect of the rack approach to separate
collection is that mixed refuse and separated paper can be
collected coincidentally by the same crew. With the rack
system, paper bundles can be picked up with mixed refuse on
regular residential collection days and placed in a separate
rack attached to the collection truck. Figure 13 shows a
typical rack configuration. Where residential collections
were made simultaneously from both sides of the street,
racks were attached to both sides of the truck.
Accordingly, refuse set-out habits of residents*need not be
altered. If curb service is provided, residents place bun-
dled paper at the curb along with mixed refuse. Bundled
paper was placed beside or on top of the mixed refuse con-
tainer when on-property collection is provided. Therefore,
the householder had the option of placing out bundled paper
each collection day. A different schedule for separate col-
lections need not be remembered.
Five rack programs were studied to obtain operational and
cost information. Table 24 summarizes each case study loca-
tion in terms of population, program initiation date, type
of material collected and collection responsibility.
Total population of the case study cities ranged from about
50,000 in Sheboygan to the two largest cities in the nation-
Chicago and New York, Population within the areas receiving
rack service, however, was considerably less than the total
in the two large cities: slightly under 10,000 in Chicago
and about 60,000 in New York. The average number of resi-
dents per household within the five case study areas was
about 3.3. The socio-economic status of the areas ranged
from middle to between middle and upper-middle.
Two of the most enduring separate collection programs in the
nation were among the five case studies. Sunset Scavenger
Company, one of two private contractors in San Francisco,
has separately collected residential refuse for over 25
years. When the firm converted their collection fleet to
compactors in 1962, racks were added to isolate newspaper
from mixed refuse. Madison implemented a rack program in
1968 with the cooperation of the American Paper Institute.
The three other sites had all been in operation less than
one year when studied.
Preceding page blank
77
-------
jure 13. Rack configuration used in Madison,
Wisconsin for separate collection of newspaper.
78
-------
TABLE 24
RACK COLLECTION PROGRAM BACKGROUND
Population (thousands)*
Materials
separately collected
Collection
responsibility
Case study location
Chicago, 111.
Madison, Wise.
New York, N.Y.
San Francisco, Calif.
Sheboygan, Wise.
j
vy .
Total
3,600
1.70
7,800
720
50
Served by
sep. coll'n.
10+
170
60*
430**
50
— rtoyrcun _____________^__ — ___ — — ——^—
initiation Other
date Newspaper paper Municipal Private
May 1972
Sept. 1968
Oct. 1972
1962++
June 1972
X V***
X V
X V
X V
x x** v
*Rounded to nearest 10,000.
+Nineteenth ward only.
#Queens Sanitation District 67 only. Several other sanitation districts receive rack
service but not studied due to lack of data.
**Residential accounts serviced by Sunset Scavenger Company only? about 60 percent of
San Francisco residents. Remaining residents receive rack service from another
private contractor.
++Sunset Scavenger Company has separated residential refuse for over 25 years. Racks
installed on compactor trucks for separate newspaper collection in 1962.
##Magazines.
***V: Voluntary household separation.
-------
The only rack case study site to separately collect material
other than newspaper was Sheboygan. Bundled magazines were
collected concurrently with newspaper, although quantities
were so small that data were not kept by program officials.
Thus, the ensuing analysis will focus on newspaper collec-
tion only.
Four of the five programs were operated by municipalities,
and one (San Francisco) was operated by a private contrac-
tor. As opposed to the small private party separate truck
programs studied, San Francisco receives separate collection
service from a large private contractor.
Each rack program operated on the basis of voluntary house-
hold participation. There were no known mandatory rack pro-
grams in existence when the case study sites were selected.
Rack Activities
Activities associated with the rack approach to separate col-
lection are shown in Figure 14 . AS might be expected, the
rack approach requires an incremental amount of collection
time at each stop when paper is separately bundled .and placed
with mixed refuse for collection. However, none of the case
study sites were able to quantify the incremental loading
time. A time study was conducted in San Francisco.15 The
incremental time required per collection stop for rack col-
lection of bundled newspapers was determined to average 14
seconds.
There were also incremental rack unloading times to be con-
sidered when evaluating feasibility of the rack approach.
Where an appreciable participation rate was attained, racks
often filled with newspaper prior to the truck filling with
refuse. Transfer operations to cope with this situation
were observed in Madison and San Francisco:
In Madison, the racks filled one to two times before
the trucks filled with mixed refuse. Each day lugger
boxes and/or dump trucks are prepositioned in the
collection areas for rack unloading. Even with pre-
positioning, each truck spent about 15 minutes off-
route per truck load (driving time and rack unloading
time).
In San Francisco, there were only a few heavy news-
paper generating routes. To circumvent the problem
of trucks leaving the route, full racks are off-
loaded at prearranged locations. A separate truck
was employed to gather and deliver the bundles to the
80
-------
HOUSEHOLD RELATED ACTIVITIES
RACK COLLECTION RELATED ACTIVITIES
(RESIDENCE)
fRESlDENTOCV
VSOLID WASTED
rt
HOUSEHOLD
SEPARATION
n
\ — I or
[(MUNICIPAL)-^-! c
RECYCLABLE
MATERIALS
HOUSEHOLD
PROCESSING
STORAGE
NON-RECYCLABLE {HOUSEHOLD
MATERIALS I STORAGE
Jr
RESIDENTIAL
SOLID WAS
COLLECTION
RACK
COLLECTION
RECYCLABLE MATERIALS
{TRANSFER
-S
MATCRiALS
TRANSPORT
MATERIALS
TO
SECONDARY
MATERIALS
DEALERS
J
I
'SECONDARY\
MATERIALS 1
DEALER J
MATERtALS
3&gure5£4~: g i
i re.ven.v-": '•-1 x-
-------
secondary materials dealer. About 5 minutes were
required to offload contents of the two racks.
Sheboygan circumvented the transfer problem completely by
discarding excess bundled paper into the truck with the
mixed refuse after the rack filled. The New York program
was not confronted with transfer operations due to a very
low participation, nor was Chicago due to severe scavenger
problems.
When the truck fills with mixed refuse (or the end of the
collection day arrives), the newspaper bundles were off-
loaded into a van or storage bin. With the exception of
New York, interim storage containers were provided and col-
lected by a paperstock dealer. New York placed a city-owned
lugger box at the disposal facility and subsequently pro-
vided transportation of containers and contents to the
paperstock dealer. At all locations, interim storage con-
tainers were placed adjacent to the disposal facility to
minimize time lost due to rack offloading. Offloading times
required from 2 to 5 minutes per truck. None of the case
study locations performed any degree of newspaper processing
after collection.
Startup Costs
Startup costs associated with rack programs were low. As
discussed in Section V, initial publicity costs averaged 15
cents per residence served. There were no reported incre-
mental labor costs associated with the rack programs. Ini-
tL&l equipment costs were limited to fabrication and instal-
lation of the rack(s).
Rack capacities ranged from a low of 0.5 cu yd in New York
to a high of 1.25 cu yd in San Francisco. The most patterned
after rack configuration was developed for use in Madison
S^K J£-a caPacitY of ab°ut 1 cu yd (refer to Figure 13 ).
Both Chicago and Sheboygan adopted the Madison configuration.
for,fabrication and installation are shown in
* ,
?n i hH«ha^ ?SSe u°* a 10W °f $8° Per rack in Sheboygan
to a high of $250 each in San Francisco.
hiVe~year Strai9ht lin^ depreciation in conjunc-
the average quantities of newspaper separately col-
lected, the amortized cost of racks ranged from $o!!o Sr
ton in Madison to $5.60 per ton in New York. The average
C°St °f racks was about one doll« per ton fo? all
82
-------
00
u>
TABLE 25
AMORTIZED STARTUP COSTS
-RACK APPROACH-
Case study location
Chicago, 111.
Madison, Wise.
New York, N.Y.
San Francisco, Calif.
Sheboygan, Wise.
Average
Startup cost/ truck
Cost/ rack
$ 100
170
100
250
80
Racks/truck
1
1
2
2
1
Total
$ 100
170
200
500
80
Average tons
collected
per truck /mo
*
7.6
0.6
6.2
1.9
5.5
Amortized
cost*
($/ton)
*
0.40
5.60
1.30
0.70
1.10
*Chicagof 111. data not included due to severe scavenger problem.
+Based on 5 year straight line depreciation; rounded to nearest $0.10.
-------
Equipment and Manpower Utilization
Table 26 summarizes truck and crew sizes used at the case
study locations. All the rack case study locations used
rear loading compactor vehicles with capacities ranging
from 16 to 25 cu yd. Crew sizes remained the same as before
implementation of separate collection — an average of 2.8
crewmen per truck.
Rack Program Performance
Rack program performance was assessed in terms of partici-
pation achieved, waste quantities diverted from disposal,
and collection productivity.
Participation. Table 27 presents performance profiles for
the rack system case study locations. Madison had achieved
the highest participation - about 40 percent. Based on a
four year average, participation in the residential sectors
of San Francisco serviced by Sunset Scavenger Company was 18
percent. The Sheboygan and New York programs received the
lowest participation rate - 10 and 2 percent, respectively.*
The average participation rate for all rack programs, 21
percent, should not be construed as typifying the rack ap-
proach due to considerations discussed in the following
paragraphs.#
With no variation iri mixed versus separate collection fre-
quency or schedule, public relations/education would appear
to be the necessary ingredient to entice greater participa-
tion in the rack programs studied. Of the case studies,
Madison provided the most program publicity through contin-
uous reports of program progress, landfill savings, etc.
Sunset Scavenger Company in San Francisco embarked on a
major publicity campaign to recycle newspaper in conjunction
with Earth Day 1970. Participation for the following six
months varied from 30 to 40 percent. The resulting quanti-
*Although not shown in Table 27, a survey of scavengers
by Chicago officials indicated that householder parti-
cipation was as high as 75 percent in the pilot area at
program onset. On-going participation waned, however,
when householders learned or observed that the sepa-
rated paper was not being collected by city forces.
ttDue to the small number of rack programs studied, gen-
eralities are often difficult to derive because uncon-
trolled program idiosyncrasies or variables can have
significant, impart, on averages drawn from small samples.
Thus, the merits or drawbacks of individual programs
will be drawn upon throughout this section.
84
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TABLE 26
EQUIPMENT AND MANPOWER
UTILIZATION:RACK OPERATIONS
Case Study Location
Chicago, I11.+
Madison, Wise.
New York, N.Y.*
San Francisco, Calif.
Sheboygan, Wise.
Average
Collection
vehicles
{no.)*
3
32
18
78
10
Vehicle
sizes
(cu yd)
20,25
16r20
20
20,25
16
20.7
Normal
crew
size
(men)
3,4
2
3
3
3
2.8
*A11 were compactor types; number used in separate
collection area only.
+Nineteenth Ward only.
#Queens Sanitation District 67 only.
85
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TABLE 27
PERFORMANCE PROFILES FOR RACK SYSTEM CASE STUDY LOCATIONS
Average Quantities Collected
Participation Total
Case Study Location* Rate Residential
Refuse
(%)
Madison, Wise. 40
New York City, N.Y.+ 2
San Francisco, Calif.* 18
CO
Sheboygan, Wise. ** 10
Total/Average 21
(tons/mo)
4,250
4,360
13,170
1,530
23,310
Separated
Newspaper
(tons /mo)
242
11
482
19
254
Disposal
Reduction
(% by Weight)
5.7
0.2
3.7
1.2
3.2
*Chicagor 111. not included due to a severe scavenger problem
distorting the program profile.
+Queens District 67 only.
^Residential accounts serviced by Sunset Scavenger Co. only (about 60
percent of San Francisco residents).
**Newspaper only. Data not available on quantities of magazines
separately collected.
-------
ties collected exceeded market demand,and the firm was
forced to curtail collection* At the time of the case
study, and in conjunction with a rising wastepaper market,
the firm was again in the process of requesting more news-
paper.
The San Francisco problem illustrates the importance of
knowing market capabilities for absorbing incremental quan-
tities of recyclable materials. Householders cannot be
motivated and demotivated at the qualms of the market with-
out losing interest in participation.
Little publicity was provided in the Sheboygan and New York
case study locations. Although the respective program offi-
cials acknowledged the need for householder motivation,
these two programs were allowed to seek their own level of
participation* It should also be noted that both programs
were in middle class communities which generally achieved
the lowest participation rates of all separate collection
programs studied - rack and separate truck.
Diverted Disposal, As shown in Table 27, only Madison and
San Francisco had significant diversion rates (about 6 and
4 percent, respectively). The same rationale provided for
participation holds true for explaining the low diversion
rates for Sheboygan and New York - i.e., no stimulation
through public relations, etc. Of positive note, however,
is the fact that the Madison program provides evidence that
the rack approach has the potential to divert significant
Waste quantities from disposal.
Collection Productivity. Productivity of the rack approach
was measured in terms of tons of newspaper collected per
truck per month. Referring to Table 25, productivity rang-
ed from less than 1 to about 8 tons per truck per month in
the case study locations. The Madison and San Francisco
programs again provide an indication of productivity poten-
tial with respective monthly rates of about 8 and 6 tons
per truck.
Program Economics
The cost of a rack program and/or its impact on overall
residential refuse collection costs is dependent on several
factors: size of the rack(s) used, participation rate
which, if appreciable, necessitates an on-route^transfer
operation, whether transportation of accumulated newspaper
is provided by the collector or the paperstock dealer, rev-
enue received from newspaper sales, and savings attributed
87
-------
to diverted disposal. Without repeating the rationale dis-
cussed in the economic analysis of the separate truck ap-
proach, both the fully allocated and incremental cost ap-
proaches to evaluating the economics of the rack approach
will!be presented.
Fully Allocated Cost Approach. Aside from rack costs, the
rack method for separate collection was not as amenable fco
analysis by the fully allocated cost approach as was the
separate truck method. The separate truck method entailed
two distinct operations: mixed refuse collection and sepa-
rate collection of recyclables. The rack approach entails
one operation entailing two functions. Because of inherent
complexities, the operation is difficult to analyze by the
fully allocated cost method.
For example, crew sizes, number of trucks, and route lengths
at all case study locations remained unaltered after rack
system implementation regardless of the fact that incremen-
tal crew time was required for rack loading, transfer oper-
ations, and rack unloading. This implies that the overall
efficiency of refuse collection was improved by utilizing
•fat" in mixed refuse collection operations to absorb the
incremental time requirements. The effectiveness of the
rack approach, therefore, is keyed to the ability of the
mixed refuse collection system to absorb the incremental
time requirements. Further generalization of the preceding
statement via fully allocated costs or averages would be
meaningless as efficiency of municipal and private opera-
tions will vary considerably from city to city.
The fully allocated cost approach can, however, be aptly
applied to special requirements generated by the ra'ck meth-
od. For example, Madison and San Francisco interim news-
paper transfer operations were necessitated by separated
newspaper quantities exceeding rack capacity prior to mixed
refuse filling the truck. Similarly, New York opted to
deliver collected newspaper to the paperstock dealer in
favor of higher revenue versus a lower revenue if a recip-
rocal agreement had been made.
The Madison transfer technique, as previously described,
consisted of daily positioning of lugger boxes and/or dump
trucks in collection areas. Positioning and retrieving
these transfer containers required an average of four man-
hours of labor per day. Equipment requirements consisted of
two dump trucks, two lugger boxes, and a hoist truck to
trans£art the lugger boxes. Including applicable fringe
benefits and administrative overhead costs, therfulily allo-
cated cost of the Madison transfer operations amounted to
$4.80 per ton of newspaper collected.
88
-------
San Francisco employed an "on-route" transfer operation arid
tai "off-route" offloading operation. The on-route taansfer
operation, as outlined earlier, consisted of emptying full
racks at prearranged locations whereupon a second truck (20
cu yd rear-loading compactor) with a one man crew reloaded
the newspaper bundles and delivered them to the paperstock
dealer. This transfer technique was conducted on a full
time basis - 5 days per week, 8 hrs per day. Although the
truck and driver were both from reserve forces, the fully
allocated cost of the newspaper transfer operations was
about $11.50 per ton.
The offloading operation was conducted at the approach to
the refuse transfer station. Two laborers were employed to
offload newspaper from the side racks, break the bundles,
check for contaminating materials, and re-load the news-
paper into a truck provided by the paperstock dealer. Each
laborer spent five hours per day offloading paper which
equated to a fully allocated cost of $1.60 per ton of news-
paper collected. Together, the transfer and offloading op-
eration amounted to an estimated fully allocated cost of
$13.10 per ton in San Francisco.
New York was the only case study location to transport col-
lected newspaper directly to .the paperstock dealer. Trans-
porting the papery which was stored in a 12 cu yd lugger box,
required one man and a hoist truck. During a six month per-
iod an average of seven trips monthly had been made to the
paperstock dealer. The fully allocated cost of transport
amounted to $28.10 per ton of newspaper.
With respect the the preceding transfer and transport costs,
and the amortized rack costs estimated in the startup cost
discussion, Table 28 presents the fully allocated costs
associated with the rack operations studied. Also shown is
the revenue received at the time of case study and in M^rch
1974, and savings attributed to diverted disposal. Two of
the four programs, Madison and Sheboygan, achieved a net
savings while New York and San Francisco operations showed
a net loss under the fully allocated approach.
The fully allocated cost analysis approach is most applicai*
ble to a collector with limited resources (equipment and
labor). Madison, New York, and San Francisco were able to
use reserve equipment and labor such that the "out-of-
pocket" costs were substantially less than the fully allo-
cated costs depicted in this assessment. For a collector
not able to utilize reserve forces, the fully allocated
costs provide insight into rack system economics.
89
-------
vo
o
TABLE
2ft
ESTIMATED FULLY ALLOCATED COST AND SAVINGS
-RACK OPERATIONS-
Case -study location*
Madison, Misc.
New York, N.Y.**
San Francisco, Calif."1"*"
Sheboygan, Wise.
Fully allocated collection coses
-------
Incremental Cost Approach. The incremental cost approach
assigns costs to the rack system only if incremental to
solid waste management costs prior to system implementation.
For example, rack amortization costs were incremental in
each location; however, transfer operations were performed
in Madison and San Francisco using budgeted equipment and
labor. Thus, in the latter two locations, only equipment
operating and maintenance costs are incremental, not equip-
ment depreciation or labor costs. The same rationale is
applicable to transporting newspaper to the paperstock deal-
er in New York.
On the other hand, the labor costs to offload newspaper at
the approach to the refuse disposal facility in San Fran-
cisco were incremental. It is in this manner that operators
providing mixed collection service viewed their costs of
implementing the rack system.
Using the incremental cost approach in conjunction with rev-
enue and disposal savings, overall collection and disposal
costs before and after implementation of the rack systems
were calculated and are shown in Table 29. As seen, each
rack program achieved a small net reduction of overall solid
waste management costs at the time of case study and an aver-
age reduction of about one and a half percent when March
1974 revenue rates were considered. Madison was able to
effectively reduce costs by over seven percent. Due to a
corporate relationship between Sunset Scavenger Company and
the paperstock dealer, the rate of newspaper revenue ($3/per
ton) was low and remained unchanged at the time of case
study and in March 1974. Substituting the average March
1974 wastepaper revenue of $31/ton received by all case
study locations (separate truck and rack, exclusive of San
Francisco) resulted in potential net reduction of over two
percent in solid waste management costs in San Francisco.
Although the Sheboygan and New York programs had low partic-
ipation rates, they were nonetheless able to attain marginal
overall cost reduction.
Again, the incremental cost approach should be used by a
municipality to bring costs into proper perspective. Fully
allocated costs are valuable, however, to independently
assess the effectiveness of peripheral operations induced
by a rack systeun.
91
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TABLE 29
IMPACT OF SEPARATE COLLECTION ON
OVERALL RESIDENTIAL SOLID WASTE
MANAGEMENT COSTS
-RACK APPROACH-
Case Study Location*
Collection and Disposal
Cost Prior to Implementation
of Separate Collection
Collection and Disposal Cost
After Implementation of
Separate Collection
Wastepaper Market
at the Time of
the Case Study
(April 1973)
Current Wastepaper
Market
(March 1974)
C$/ton)
($/ton) (% Change) ($/ton) (% Change)
to Madison, Wise.
New York, N.Y.+
San Francisco, Calif.*
Sheboygan, Wise.
22.30
53.50
30.50
32.00
22.QO
53.40
30.40**
31.80
-1.3
-0*2
-0.3
-Q.6
20.70
53.40
30.40**
31.70
-7.2
-0.2
-0.3
-0.9
*Chicago, 111., not included due to a severe scavenger problem distorting the program results.
+Queens District 67 only.
fResidential accounts serviced by Sunset Scavenger Company only (about 60 percent of San
Francisco residents).
**NQ change was .made in the newspaper revenue/rate received between April 1873 and March 1974
(see text).
-------
Model Economics for the Rack Approach
The effectiveness of the rack approach to separate collec-
tion depends on the ability of the mixed collection system
to absorb the incremental time requirements for paper col-
lection and transfer. Due to the many variations between
refuse collection systems, it is difficult to describe and
evaluate an average case for capability to absorb incremen-
tal time requirements. However, by using the Madison rack
collection procedures* as exemplary, a hypothetical munici-
pality of 10,000 households was evaluated via the adapted
collection model (Appendix E) to illustrate the effect of
instituting rack operations on an efficient collection sys-
tem where no additional collection time requirements could
be absorbed without additional equipment and labor. The
results of the analyses are presented in Figures 15 and 16
depicting short and long disposal haul situations/ respec-
tively. Each figure shows the effective collection costs
per month after implementation of rack operations for the
hypothetical municipality reflecting revenue rates of $8
per ton and $25 per ton and the extremes of possible dis^-
posal cost savings (i.e., first party landfill to second
party incinerator). Also plotted for comparative purposes
is the estimated baseline cost for mixed refuse collection
prior to implementation of rack operations (designated
"combined refuse collection cost").
The discontinuities shown in the short haul situations
(Figure 15) delineate points (35 and 70 percent participa-
tion) where off-route transfer of newspaper is required.
At these points, a quantum increase in cost is incurred by
a collection system unable to absorb incremental time
requirements. The relationship reflecting revenue at $8
per ton shows savings exceeding collection cost only under
the circumstances of less than 35 percent participation
(no transfer operations required) and second party incin-
erator disposal savings.
The economic projections with revenue at $25/ton are more
favorable. Incremental costs are more than covered by sav-
ings when participation is less than 35 percent. Although
not as substantial, costs were almost always covered between
35 and 70 percent while only savings attributed to diverted
*Madison used 20 cu yd rear-loading compactors for mixed
collection, each equipped with a one cu yd rack to isolate
separated newspaper bundles. Labor consisted of a driver
and a loader (i.e., 2 man crew), and mixed/separate col-
lection was made once per wk. The "on-route" transfer
system consisted of prepositioned lugger boxes.
93
-------
w
TJ
iH
O
XI
oj
en
3
O
o
O
o
HJ
C 0
O13
s.
m
n o
o>
a w
t)
+J c
to m
o w
U a
§5
O
0)
H
rH
a
0)
>
•H
-P
O
(1)
17
16
15
14
13
12
11
10
Paper market at time of
case studies (April 1973)
$8/ton.
[Assumed paper market:
$25/ton.
' Combined
Refuse
Collection
Cost
j/Points where
(^off-route
transfer of
newspaper is
required
0 10
20
80
90 100
30 40 50 60 70
Percent Participation
Figure 1,5. Effective^ cost for rack collection of*separated
newspaper versus combined refuse collection cost prior
n "
94
-------
22
CO
CO
3
O
K
O
O
O
O CO
nj
33
c o
5-d
33
0)
j to
•H ~
•P
O
(1)
5
o
0)
21
20
19
18
17
16
15
Combined
Refuse .
Collection
Cost
Point where incremental ^
time requirements prevent
crew from returning to
collection route for second
(or partial) load.
Paper market at time of
case studies (April 1973): $8/ton
Assumed paper market: §25/ton
0 10 20 30 40 50 60 70 80 90 100
Percent Participation
Figure 16 . Effective cost for rack collection of
separated newspaper versus combined refuse collection
cost prior to system implementation: exemplary analysis
for long haul situation.
95
-------
incinerator disposal costs were generally able to effective-
ly decrease collection cost beyond a participation of 70 per-
cent.
The long haul situation (Figure 16) portrays the impact of
having the separate collection subsystem {i.e., the rack)
off the collection route for extended lengths of time. The
discontinuity at 20 percent participation in the long haul
relationship represents the point in hhe hypothetical ex-
ample where incremental time requirements become so severe
that collection trucks are unable to collect more than one
full load per day (i.e., there is not sufficient time for a
truck to return to the route for a second load) „ .-Economic
feasibility in the long haul example is indicated only at
participation rates less than 20 percent and some situations
exceeding 70 percent in conjunction with the $25 per ton
revenue.
In practice the case study rack operations have been able to
absorb the incremental time requirements without increasing
the number of crews and/or equipment. The cawe study loca-
tions had also not attained participation in excess of 40
percent.
Economic application of the rack approach is thus limited
by a number of factors. In some cases, features desired in
an efficient collection system for mixed refuse are diamet-
rically opposed to rack collection efficiency. For example;
* Truck capacity - as the capacity of the collection
vehicle increases, so does the corresponding abil-
ity to stay on the route for greater lengths of
time, a desired feature in mixed refuse collection
systems. However, the need for transfer of news-
paper before completion of a full truck load will
increase accordingly.
• Compaction capability - similar to truck capacity/
greater compaction with commensurately sized trucks
will result in more on-route time and increased
mixed refuse collection efficiency. Again, however,
the need for transfer of rack-held newspaper will
increase.
• Auxiliary engines - compaction between stops, re-
duced noise, and lower maintenance costs are often
cited as justifying the use of an auxiliary engine
on the collection vehicle. However, on some truck
types, the space utilized for the engine is also
the most suitable location for the rack.
96
-------
Diverted disposal quantities - paper revenues and
diverted disposal savings increase with the quanti-
ties of paper collected. However, as participation
in a rack program grows, the racks fill more quickly
while the reduced quantities of mixed refuse allows
the collection vehicle to remain even longer on the
collection route.
Truck capacity and compaction capability have a subtle re-
lationship. For wxample, a location using 16 cu yd compac-
tors capable of achieving 500 Ib per cu yd density would be
a better candidate for rack collection use than a second lo-
cation employing 20 cu yd trucks achieving 1,000 Ib per cu
yd density. Given equal crew efficiency, mixed refuse gen-
eration rate, and participation in a separate newspaper col-
lection program, the collection trucks in the latter location
could remain on route up to 2.5 times longer for each load.
Accordingly, newspaper transfer would be required more fre-
quently.
Conversely, in a community where existing resource recovery
activity is substantial through local recycling centers or
church/school paper drives, the rack approach to separate
collection may operate economically with low generation
rates, whereas the separate truck approach could not.
97
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VII
ACKNOWLEDGEMENTS
We gratefully express our appreciation to representatives
of the Resource Recovery Division of the Office of Solid
Waste Management Programs, Environmental Protection Agency,
for their encouragement and assistance in the conduct of
this study. Ms. Penelope Hansen, Project Officer, provided
excellent guidance throughout the study. Her dedication and
sincere interest in resource recovery provided helpful en-
couragement to members of the project team.
The assistance of the many public works administrators, pri-
vate refuse collection firms, and concerned citizens who
contributed information to the case studies comprising the
basis for this study is gratefully acknowledged. .
Preceding page blank
99
-------
VIII
REFERENCES
1. "Newspaper Pipeline Reopens but Only a Trickle Is
Expected," Los Angeles Times/ December 3, 1973.
2. Analj2j.ng Supply/Demand Conditions in the West Coast
Used Newspaper Market, Unpublished study performed for
the Garden State Paper Company by McKinsey and Company*
July 1973.
3. "Russia Ups Newsprint Price Whopping 135%," Los Angeles
Times, March 10, 1974.
4. Recycling Solid Wastes in Los Angeles, Bureau of Sani-
tation, Department of Public Works, City of Los Angeles,
California, May 1971.
5. Refuse Collection Practice, American Public Works
Association, third edition, 1966.
6. Peters, William H., "Who Cooperates in Voluntary
Recycling Efforts?", Unpublished paper presented at the
American Marketing Association Conference, August 1973.
7. Metropolitan Housewives* Attitudes Toward Solid Waste
Disposal, prepared by National Analysts, Inc. for the
U.S. Environmental Agency, Report No. EPA-R5-72-003,
September 1972.
8. "Pollution Control in the Local Community: Citizen
Attitudes and Willingness to Make Personal Sacrifices
in Abatement," Toledo Business Report, Occasional Paper
No. 23, University of Toledo Business Research Center/
Toledo, Ohio, December 1973.
9. "More Willing to Tax Selves to End Pollution," St.
Louis Globe-Democrat, July 26, 1971 (Harris Poll).
10. "Time Studies of Separate Paper Collection: Separate
Truck Methods, Fort Worth, Texas," prepared by SCS
Engineers for the U.S. Environmental Protection Agency
under Order No. P4-01-00741, November 27, 1973.
11. Recovery and Utilization of Municipal Solid Waste/
Battelle Memorial Institute, study for the U.S.
Environmental Protection Agency, 1971.
Preceding page blank
-------
REFERENCES (Continued)
12. "U.S. Statistics Show Annual Salaries of Crewmen,"
Solid Wastes Management/Refuse Removal Journal,
January 1973, pg. 34.
13. A Study of Solid Waste Collection Systems Comparing
One-Man and Multi-Man Crews, U.S. Department of Health,
Education and Welfare, Bureau of Solid Waste Manage-
ment, Report No. SW-9C, 1969.
14. Quon, J.E., "Refuse Quantities and Frequency of Ser-
vice," Journal of Sanitary Engineering, American
Society of Civil Engineers, April 196~8.
15. "Time Study of Separate Newspaper Collection: Rack
Method," prepared by SCS Engineers for the U.S.
Environmental Protection Agency, under Order No.
P3-01-03692, June 1973.
16. Water and Power Facts, Department of Water and Power,
City of Los Angeles, California, 1972.
17. Sorg, T.J. and H.L. Hickman, Jr., Sanitary Landfill
Facts, Report Number SW-4ts, U.S. Department of Health,
Education and Welfare, Bureau of Solid Waste Manage-
ment, 1970.
18. Municipal Refuse Disposal, American Public Works
Association, 1970.
19. Solid Waste Bags System Study, City of Inglewood,
California, Department of Health, Education, and Wel-
fare, Bureau of Solid Waste Management, 1970.
20. Duncan, A.J. Quality Control and Industrial Statistics,
Richard D. Irvin, Inc., 1965.
102
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IX
APPENDICES
Section Page
A Incurred Material Preparation Costs A-l
B Revenue and Diverted Disposal Values B-l
C Collection Model C-l
D Separate Truck Systems Analyses D-l
E Rack Systems Analysis E-l
103
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APPENDIX A
INCURRED MATERIAL PREPARATION COSTS
Material preparation costs incurred by a householder may
include costs for water used when rinsing or cleaning mate-
rials, energy used if metal container volume reduction
requirements are accomplished with the aid of an electric
can opener, and the amount of time^used when bundling news-
paper. Data to estimate the incurred costs were obtained
during the voluntary household study conducted in conjunc-
tion with the primary study. This appendix delineates the
amount of supplies and resources used and estimates the
householder costs incurred for each of three material
preparation activities: cleaning, volume reduction, and
bundling.
Cleaning
The average time spent cleaning separated containers totaled
5.4 person-minutes per week. On a material by material
basis the average wefikly cleaning time and material amounts
cleaned were as follows:
Average weekly Average weekly
cleaning time generation rate
Material (min.) (Ibs)
Glass
Tin/bi-metal
Aluminum
2.4
2.3
0.7
4.5
1.7
0.3
Total 5.4 6.5
The average rate of water flow used during rinsing and
cleaning of containers was computed to be approximately one
gallon per minute (gpm) . The cost of residential water was
estimated to be $0.0005 per gallon based on a survey of
water rates in the sixteen largest cities in the United
States16 (Note: case studies were conducted in nine of
these cities). Water used during cleaning is dependent on
the portion d>f time that water is actually used for cleaning
purposes. For example, if dishwater is used both for con-
tainer cleaning and for washing dishes, no incremental
water cost was assigned for cleaning. Conversely, if tap
water was kept running throughout the cleaning exercise, the
total quantity of water was attributed to cleaning.
A-l
-------
Participants in the household study did not use soap for
cleaning separated containers, unless soap was in used
dishwater. Similarly, mechanical dishwashers were not used
for cleaning containers. Thus, no incremental costs were
assigned for soap or for dishwasher use.
Table A-l converts the time/quantity data above to incurred
cleaning costs at the average water cost rate.
Based on average generation rates, Table A-2 presents the
number of months required to produce one ton of each mate-
rial and converts the cleaning cost per ton to a cost per
household per month.
Volume Reduction
Aluminum containers can be readily crushed without mechani-
cal assistance. Glass containers are not normally crushed
in the household due to the potential hazards of broken
glass. Therefore, tin/bi-metal containers were the only
separated material to which incurred volume reduction costs
were attributed.
Household studies indicated that when volume reduction was
performed, an average of 2.2 minutes were spent crushing
the 1.7 Ibs of tin/bi-metal plated containers generated
weekly. As an aid to volume reduction, the normal procedure
was to cut the top and bottom from the container and flatten
the resulting cylinder. Removing the container top is a
utilitarian procedure and was therefore not attributable to
material preparation costs. Removing the container bottom
for ease of crushing was, however, and therefore an attrib*-
utable material preparation cost.
Bottom removal may be accomplished manually with a hand-held
can opener or mechanically with an electric can opener.
Removing the container bottom consumed about 90 percent of
the total crushing time with no significant time differences
between the two removal methods. Assuming typical electric
can opener has a rating of 160 watts, and electricity costs
$0.015 per KWR16, the weekly cost of electricity was approx-
imately $0.00009 which is equivalent to about $0.10 per ton
of tin/bi-metal containers reduced in volume. As previously
estimated, 278 months would be required to produce one ton
of tin/bi-metal containers. Thus, when volume reduction
was accomplished with the aid of an electrical can opener,
the incurred household cost was about $0.0004 per month.
Conversely there was no incurred cost when manual aids such
as a hand-held can opener were used (no hand-held can
openers were purchased specifically for volume reduction
during the household studies).
A-2
-------
TABLE A-l
CLEANING COST CALCULATIONS
Material
Material Cleaning
Weekly water cost conversion generation cost
CGal/Wk) x ($/Gall = t$/WkX Clbs/wk)
Glass
Tin/Bi-metal
Aluminum
Total/Average
2.4
2.3
0.7
5.4
0.0005 0.00120 4.5
0.0005 0.00115 1.7
0.0005 0.
0.0005 0.
TABLE A- 2
CLEANING COSTS PER
Material
Glass
Tin/Bi-metal
Aluminum
Cleaning
cost
($/ton)
0.53
1.35
2.33
Material
generation
Rate*
(Ibs/mo)
19.3
7.2
1.3
00035 0.3
00270 6.5
HOUSEHOLD
Time required to
accumulate one
ton of material
per household*
(mo)
104
278
1,538
($/ton)
0.53
1.35
2.33
0.83
Incurred
cost per
household
($/mo)
0.0051
0.0048
0.0015
*Based on generation rates determined from household study.
•fRounded to nearest whole month.
-------
Bundling
Incurred bundling costs occur only when twine or a similar
material is used to bind newspapers. Bundling serves to
ease handling and reduces litter problems during collection
or delivery. Grocery bags may be used to accomplish this
purpose; however, no incremental costs were assigned if this
method was used.
About 30 percent of the household participants voluntarily
bundled newspaper with twine. About 2.6 ft of twine per
week was used to bundle an average of 12.2 Ibs of newspaper
generated weekly. The cost of twine was estimated to be
$0.001 per linear foot equating to a cost of $0.43 per ton.
At a rate of 12.2 Ibs per week (52.8 Ibs per month) approxi-
mately 38 months would be required to generate one ton of
newspaper. Thus, the incurred household cost per month was
$0.011, or about a penny per month if bundling was accom-
plished with twine.
A-4
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APPENDIX B
REVENUE AND DIVERTED DISPOSAL VALUES
Separately collected materials have a revenue value and a
diverted disposal value. Each has a bearing on separate
collection economics regardless of the approach used to
evaluate a program.
Revenue
Revenue has an important influence on program economics. In
March and April, 1973, when the case studies were conducted,
wastepaper market prices ranged from $4 to $14 per ton with
an average of $8 per ton. In March 1974, the same case
study locations were receiving wastepaper revenues ranging
from $12 to $56 per ton with an average of about $30 per
ton. Glass and mixed metal revenues remained virtually
unchanged, however, with glass programs ranging from $10 to
$20 per ton ($15 per ton average) and mixed metal revenues
at $10 per ton.
Diverted Disposal Savings
Savings in diverted solid waste disposal costs resulting
from separate collection are principally dependent on
whether the municipality operates its own disposal facility
or pays a second party for disposal. In a secondary sense,
the savings vary with the cost of the disposal method em-
ployed.
In the twenty-two case study locations (separate truck and
rack), disposal was either by sanitary landfill or incinera-
tion. If the municipality pays a second party for disposal,
the entire disposal cost per ton can be recovered through
separate collection. If the disposal facility is owned and
operated by the municipality, however, only a portion of
the disposal cost can be saved. None of the case study
locations in the latter category had attempted to quantify
the portion of cost applicable to diverted disposal. There-
fore, diverted disposal savings for landfill and incinera-
tion operations were estimated in the manner discussed
below.
Sanitary Landfill. Benefits of separate collection on sani-
tary landfill operations include a decrease in the rate of
use of remaining landfill space and a decrease in landfill
equipment usage. Based on the case studies, reported sani-
tary landfill ownership and operating costs ranged from
B-l
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$0.85 to $7.50 per ton with an average of about $2.50 per
ton. Land costs were assumed to represent $0.50 of the
total cost based on the disposal of 10,000 tons per acre
and a net land cost of $5,000 per acre. Thus, separate col-
lection of recyclables was assumed to potentially save $0.50
per ton in land costs at the sanitary landfill.*
The remaining $2 of the total $2.50 per ton was attributed
to operating costs. Assuming a track dozer can spread and
compact up to 80 tons of solid waste per hourl? and that
equipment and operator costs average $25 per hour, an addi-
tional operating cost savings of about $0.30 per ton can be
attributed to wastes diverted by separate collection. Thus,
a total diverted disposal cost savings of $0.80 per ton
was assigned when a municipality owned and operated its own
sanitary landfill while the total disposal cost per ton was
assigned in cases where municipalities paid a second party
for disposal.
Incineration. The diversion of materials from incineration
through separate collection activities can be expected to
reduce equipment usage and residue disposal requirements.
Incineration costs reported for the case study locations
ranged from $7.20 to $17.40 per ton with an average of
$10.50 per ton. A breakdown of incinerator operating costs
was provided for Chicago, Illinois18 (a rack case study
location). Table B-l presents an estimated breakdown of
incinerator cost elements believed to be affected as a
result of refuse tonnage diverted via separate collection.
Assuming applicability of the tabulated data to the case
study locations, savings from diverted materials amounts to
51 percent of the total cost per ton for incineration.
In addition, ash residue must be hauled for final landfill
disposal. Residue transport costs vary with many factors,
but for purposes of this study, savings were assumed to
average $0.50 per ton of residue. Disposal cost of residue
at the landfill was valued at $0.80 per ton for a munici-
pally owned landfill and the total cost per ton for second-
party ownership based on the preceding landfill discussion.
A 95 percent reduction in weight of material was assumed for
paper processed through an incinerator. No weight reduction
was attributed to glass and metal if processed through an
incinerator.
*Fort Worth, Texas, was the only case study location that
was able to provide an estimate for land costs: $0.57
per ton.
B-2
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TABLE B-l
INCINERATION COST ELEMENTS AS A PERCENTAGE
OF TOTAL PLANT OPERATING COSTS
Percent of total
Operating cost element operating cost
Applicable
to diverted
tonnage
Operating less residue
disposal
Maintenance and repair
Administration and
supervision
Pension
Fuel and utilities
Amortization
Mi s ce 11 ane ous
27
22
8
4
2
20
.._17
100
27
22
0
0
2
0
_0
51
B-3
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APPENDIX C
COLLECTION MODEL
The many approaches to performing refuse collection and/or
separate collection of recyclable materials can be described
with a mathematical model. The model defines the mathemati-
cal relationships between collection time, tonnage col-
lected, haul time, equipment capacity, costs, and other fac-
tors. Through repeated calculations, the model may be used
to analyze alternative collection approaches to minimize
and/or compare applicable costs.
The following factors affecting the efficiency of mixed or
separate refuse collection were included as variables in
the model:
1. Average quantity of mixed or recyclable material(s)
generated per residential unit.
2. Average collection time for each residential unit,
including travel time to the next stop.
3. Average driving time between the route and the
disposal site (secondary material dealer, transfer
facility, or final disposal site).
4. Total non-productive time: travel time between
yard (vehicle storage area) and route and between
the disposal site and the yard; breaks (lunch,
coffee, relief); and dispatch.
5. Average offloading time per load at the disposal
site.
6. Crew size.
7. Equipment type, capacity, and performance
characteristics.
The following assumptions were used during the calculations:
1. The minimum partial load allowed was one-fourth of
the vehicle load capacity (i.e., a collection
vehicle was not allowed to return to the collection
route after emptying a full load unless sufficient
time remained to collect at least a quarter of a
load).
C-l
-------
2. The maximum work day was constrained to 480
minutes.
3. Crew members were paid for eight hours (480
minutes); if time was not sufficient to coliect
a partial load, they were dismissed early, but
paid for 8 hours.
Physical and cost variables used in the model were defined
as follows:
Physical Variables
Xn: Total time to collect and offload n loads (crew
min/day).
Vc: Vehicle capacity (cu yd).
t: Average collection time per stop plus travel time
to the next stop (min).
d: Average density of material in the vehicle
(Ibs/cu yd).
Q: Average quantity of material per stop (Ibs).
B: Average one-way driving time between route and
disposal site (min).
D: Average disposal time (min).
K: Total non-productive time per day - includes
dispatch, breaks, yard to route time, and disposal
site to yard time (min).
Cost Variables
Cc: Cost of collection labor ($/crew-min).
Cv: Cost of collection vehicle ($/truck-min).
R: Revenue from materials separately collected
($/ton).
S: Disposal savings from materials separately
collected ($/ton).
Alternative collection frequencies may be evaluated by
changing the value of'the average quantity of material col-
lected per stop (Q) in proportion to the monthly generation
rate. For example, evaluation of a separate newspaper
C-2
-------
collection program where once per month collection is to be
performed and the average residential generation rate is
40 Ibs/mo would have a Q value of 40 Ibs. If weekly col-
lection is to be evaluated, a Q value of 9.2 Ibs would be
used (40 4 4.33 weeks/mo).
Various participation rates may be evaluated by changing the
value of the average collection time per stop (t). As
previously defined, the value of t is comprised of the time
to collect materials per stop (i.e., dismount truck, load,
remount truck) plus the driving time to the next stop. The
collection portion of t is assumed to a constant at a spe-.
cific collection frequency due to the average quantity of
material collected per stop being held constant.
The second variable in the time calculation, travel time to
the next stop, is a function of participation rate. An
even distribution of participants and material generation
along a 10-home segment of a route should be assumed. For
example, if an overall participation rate of 10 percent is
to be evaluated and one side of the street collection is
performed, the assumption that one out of each ten homes
along the route would be made. Thus, travel time would be
calculated based on collecting materials at the first home
on the route and driving past the subsequent nine homes to
the next participant. Similarly, a 50 percent participation
rate may be evaluated by assuming a collection stop is made
at every other home along the route.
Calculations
Using the variables discussed above, a series of seven cal-
culations are necessary to evaluate the performance and
cost characteristics of collection operations:
1. Calculate the time to collect the first and
I successive loads.
2. Convert collection time into collection cost.
3. Determine tonnage collected.
4. Determine number of residences served.
5. Convert tonnage collected into dollar savings
(revenue plus diverted disposal savings).
6. Compute net cost of separate collection
(collection cost less savings).
7. Convert net cost into meaningful factors
(cost/ton, cost/residence).
C-3
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Step 1; Collection Time Calculation
The total time in minutes to complete one load (collect and
offload) can be calculated as follows:
X1 = Vctd + B + D + K
Q
At the disposal site, a decision is made:
Jf Xi + 2B + D = 480, only one full load will be
collected for the day;
if Xi > 480, only a single partial load will be
collected for the day/ and the following calculation
is made:
480 = (a) Vtd + B + K + D.
Q
Solving for the value of (a) gives the fraction of
the truck capacity used for the partial load;
if Xl + 2B + D < 480, the truck is sent for a
second or more loads as time permits*
In general, the truck makes a total of n trips, where:
Xn: = (n + a - 1) Vctd + <2n - 1) B + K + nD
Q
provided Xn < 480 < Xn+l, and a £ 1/4;
if a < 1/4, only (n - 1) trips are made.
The results provide the collection time in terms of crew-
minutes per day and the quantity of material collected by
the vehicle. In this case, crew members were paid for a
480 min day even if finished early. If collection time
were not constrained and overtime permitted, appropriate
modifications would be required to the preceding equations.
Step 2; Collection Cost Calculation
Under the conditions imposed, crew members are paid for a
full day's work even if finished early. This condition will
not always be the case. Therefore, labor costs should be
converted to a cost per crew per min ($/min) based on the
cumulative hourly rates of driver and loaders including
overhead and/or fringe benefits to readily convert the daily
C-4
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collection time, Xn, into labor costs. Similarly, vehicle
costs (amortization, overhead, fuel, oil, and maintenance)
should be converted to a cost per vehicle per minute ($/min)
so that vehicle costs can be apportioned. Generally, daily
collection time can be converted to cost as follows:
Daily Collection Cost = Xn (Cc + Cv)
When an undertime situation occurs, the collection .cost
relationship is as follows:
Daily Collection Cost = 480 Cc + 1480 - (480-Xn) 3 Cv
This relationship credits undertime for vehicle usage.
Step 3: Tonnage Collected Calculation
Revenue is based on tonnage of recyclable materials col-
lected. The volume of material collected per day can be
converted to tonnage by the following relationship:
Tonnage Collected = %- Vd
2,000
The volume (V) may be calculated by multiplying the truck
capacity (Vc) by the number of full and partial loads col-
lected in Step 1. Average density (d) is derived from
weighings of loaded vehicle weights, subtracting the vehicle
tare weight, and dividing by
Step 4; Residences Served Calculation
The number of residences served per day by each crew depends
on many factors: participation rate, truck volume, crew
size, etc. The factors required to estimate residential
service rate, however, will have been developed during
Step 1. Thus, the service factor may be estimated :by
dividing the multiplicative sum of the volume collected and
density by the average quantity of materials per stop:
Services =
Step 5; Dollar Savings Calculation
Revenue (R) from recyclable materials and diverted disposal
savings serve to reduce overall collection costs. Revenue
is readily calculated by multiplying tonnage collected
(Step 3) by the rate paid by a secondary materials dealer
for a specified material.
C-5
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Diverted disposal savings (S) are calculated based on local
disposal conditions. These savings should consider first
and second party costs. For example, if Municipality A is
paying private landfill operator B for disposal, the entire
unit disposal cost should be credited to the separate col-
lection operations for each ton of material diverted. How-
ever, if Municipality A owns and operates the landfill,
only a portion of the unit cost should be attributed to the
diverted materials. (A sum of $0.80/ton was used as a proxy
for these "first party" landfill diverted disposal costs.)
Incineration costs should be handled similarly. Municipali-
ties paying a second party for incineration should credit
the entire unit cost to separate collection operations. As
a proxy for first party diverted disposal costs, 50 percent
of the incineration costs can be used (based on cost allo-
cation of Chicago incinerator costs)18 plus incinerator
residue disposal costs (again allocated on a first-and-
second party basis).
Step 6; Net Collection Cost Calculation
The net cost of separate collection operations is calculated
by subtracting the results of Step 5 from the results of
Step 2:
(Total separate (Revenue plus di- _ (Net separate
collection cost) ~ verted disposal cost) ~ collection cost)
or
(Step 2) - (Step 5) * Step 6
Step 7: Performance Factor Calculation
Based on the net cost calculation (Step 6), performance
measures such as cost/ton and cost/residence can be calcu-
lated. Net cost per ton is calculated by simply dividing
cost by the tonnage collected:
Net Cost per Day Step 6
Tonnage Collected per Day or Step 3
The cost per residence per month is calculated by dividing
the daily cost by the number of residences serviced per day
(Step 4) and multiplying this sum by the collection fre-
quency (in terms of collections per residence per month):
Cost per Net Cost per Day x Collections per
Residence = Number of Residences Residences per Month
Served per day
C-6
-------
or
Step 6 Collection Frequency
Step 4 x Factor
where
Frequency of Collection Factor
Once per month 1
Once per 2 weeks 2.16
Once per week 4.33
C-7
-------
APPENDIX D
SEPARATE TRUCK SYSTEMS ANALYSIS
The analysis to assess the optimal impact of separate col-
lection operations via the separate truck approach with
respect to overall collection costs* is presented in this
appendix. The analysis presented herein was performed using
the adapted collection model described in Appendix C. The
model output estimates collection costs prior to imple-
menting a separate collection subsystem and the effective
cost of collection after implementation of separate collec-
tion. The effective cost accounts for rerouting of mixed
refuse collection vehicles reflecting reductions in quantity
of waste per stop due to separate collection of newspaper.
The conditions analyzed are shown in Table D-l. As shown/
the analysis considers variability in mixed and separate
collection parameters in terms of: truck capacity, crew
size, collection frequency, haul distance, disposal savings,
revenue received from newspaper sales, and percent partici-
pation in the separate collection program.
Data Development
Data used to exercise the model are presented in Table D-2
and discussed in the ensuing text.
Collection vehicle capacity (Vc) for mixed refuse collection
operations were 16, 20, and 25 cu yd when rear-loading com-
pactor vehicles were considered, and 20 and 25 cu yd for
side-loading compactors. Separate collection alternatives
considered 12, 16, 20, 25 cu yd rear-loaders and 20, 25
cu yd side-loaders. The vehicle costs (Cv) were estimated
to be $3 per hr ($0.050 per min) for the 12 cu yd truck;
$4 per hr for 12 and 20 cu yd trucks ($0.067 per min); and
$5 per hr for the 25 cu yd trucks ($0.083 per min).
Crew costs were based on national averages^2, plusi 25 per- •
cent fringe benefits. Drivers pay rates were $5.80 per hr
and loader rates were $4.70 per hr. Thus, a one-man crew
(driver) was valued at $0.098 per min for an 8-hr work day.
Correspondingly, a two-man crew (driver and loader) at
$o7l74 per min and a three-man crew (driver and two loaders)
at $0.254 per min.
^Overall collection costs considers the costs of both
mixed and separate collection.
D-l
-------
TABLE D-l
CONDITIONS ANALYZED VIA THE
ADAPTED REFUSE COLLECTION MODEL
Variable
Mixed
Collection
Separate
Newspaper
Collection
Crew Size (no./
vehicle)
Collection frequency
Collection location
Vehicle capacity
(cu yd)
Generation rate (Ibs/
household/wk)
Labor cost
Haul distance
Disposal savings
Revenue ($/ton)
Percent participation
1-Side loader
21
3?Rear loader
l/wkr 2/wk
curb
16,20,25 rear
loader
20,25 side loader
61*-l/wk coll'n
79+-2/wk coll'n
National average^
$5.80-driver
$4.70-loader
Short haul, long
haul
1-Side loader
3[.Rear loader
1/wk, l/2wk, 1/mo
curb
12,16,20,25 rear
loader
20,25 side loader
7 (newspaper only)
National average'
$5.80-driver
$4.70-loader
Short haul
Landfill and in-
cineration (first
and second party
costs)
8,25
20,50,80
*Based on 2.5 Ibs per person per day and 3.5 persons per
household.
Based on research by Quon, generation rate increases
»with collection frequency. *
fIncludes 25 percent fringe benefits.
D-2
-------
ui
TABLE D-2
DATA FOR EXERCISING THE COLLECTION MODEL
-SEPARATE TRUCK APPROACH-
Variable
Vc (cu yd)
Rear loader
Side loader
t (min)
Mixed: 1/wk
. 1-man
. 2-man
. 3-man
Mixed: 2/wk*
. 1-man
. 2-man
. 3-man
Sep. : 1/wk
. 1-man
. 2-man
. 3-man
Mixed
Prior to Sep.
Collection
16, 20, 25
20, 25
.76
.69
.60
.68/.S9
.61/.52
.S4/.46
Refuse Collection
After Sep. Collection/ Separate Collection/
Participation Rate Participation Rate
20
.76
.68
.60
.68/.S9
.61/.51
.S4/.46
50
16, 20,
20,
.75
.67
.59
.67/.5S
.60/.51
.S3/.45
80 20 50 80
25 12, 16, 20, 25
25 20, 25
.74
.66
.58
.66/.S7
.59/.50
.S2/.44
.51 .33 .24
.49 .31 .22
.48 .30 -21
-------
TABLE D-2 (Continued)
Variable
Sep. : 1/2 wk
1-man
2-man
3-man
Sep. : 1/mo
1-man
2-man
3-man
d (Ib/cu yd)
Q (Ibs)
Mixed
. 1/wk
. 2/wk*
Separate
B (min)
Long haul
Short haul
Mi^ed Refuse Collection
Prior to Sep. After Sep. Collection/
Collection Participation Rate
20 50 80
650 650
61 60 57 55
47/32 46/31 45/30 44/29
15 15
45 45
Separate Collection/
Participation Rate
20
.53
.51
.50
.59
.56
.54
7
50 80
.35 .26
.33 .24
.32 .23
.41 .32
.38 .29
.36 .27
650
14 30
15
15
-------
TABLE D-2 (Continued)
o
en
Variable
D (min)
K (min)
Cv ($/min)
12 cu yd
. 16,20 cu yd
. 25 cu yd
Cc ($/rain)
1-man
2-man
3- man
Mixed
Prior to Sep.
Collection
15
120
.067
.083
.098
.174
.254
Refuse Collection
After Sep. Collection/
Participation Rate
20 50 80
15
120
.067
.083
.098
.174
.254
Separate Collection/
Participation Rate
20 50 80
15
120
.050
.067
.083
.098
.174
.254
*Reflects time or weight estimates for first/second collection day per week.
-------
The average compacted density of combined refuse (d) with
or without newspaper, was assumed at 650 Ibs per cu yd.
Compacted newspaper was also estimated at 650 Ibs per cu yd
based on measurements taken in Fort Worth, Texas.10
The average normal quantity of combined refuse per stop (Q)
for once per week mixed refuse collection was calculated
based on 3.5 persons per residence and 2.5 Ibs of solid
waste generated per person per day. The resulting average
quantity of residential solid waste per stop was estimated
to be 61 Ibs per week. Assuming 7 Ibs of newspaper per
household per week, the remaining quantity of combined
refuse with all newspaper removed (100 percent participation
rate) was 54 Ibs. The quantity of combined refuse per col-
lection stop at the exemplary 20, 50, and 80 percent partic-
ipation rates was calculated assuming participating stops
generate 54 Ibs and non-participating stops generate 61 Ibs
of combined refuse on a weekly basis. For those combina-
tions involving twice weekly collection, the normal quantity
was assumed to increase 30 percent (to 79 Ibs per week),
with 60 percent of the total collected on the first collec-
tion day of the week and the remainder collected on the
second day. -H
The average times per stop (t) for collection of mixed
refuse prior to and after separate collection of newspaper
were derived from studies of solid waste collection systems
comparing one-man and multi-man crews!3 based on the fol-
lowing rationale.
Containers for storage of combined refuse were assumed to
be 32-gal metal or plastic containers. Container utiliza-
tion was estimated to average 91 percent with an average
loose refuse density of 163 Ibs per cu yd.19 Based on these
factors, the required number of storage containers were com-
puted and tabulated in Table D-3. Separate collection of
newspaper should reduce the number of storage containers
(on the average) required for the remaining refuse. Since
newspaper quantities are relatively small compared to the
total quantity of mixed refuse, a rational method for the
assessment of container requirements was sought. Graphical
data describing the number of containers per stop was found
to resemble the Poisson statical distribution. (The general
form of the distribution is depicted in Figure D-1.20)
Using the average number of refuse containers per stop from
Table D-3 in conjunction with the Poisson distribution, the
probability associated with finding certain numbers of
storage containers per collection stop was calculated.
D-6
-------
TABLE D-3
ESTIMATED NUMBER OF STORAGE CONTAINERS
FOR RESIDENTIAL REFUSE
Avg. No. of
Collection Containers
Refuse Collected Freqqency Per Stop
Mixed refuse 1/wk 2.60
Mixed refuse less newspaper 1/wk 2.34
Mixed refuse 2/wk (1st day) 2.04
(2nd day) 1.32
Mixed refuse less newspaper 2/wk (1st day) 1.83
(2nd day) 1.24
D-7
-------
0.30--
o
z
LJ
O
o
fc
0.20- •
D
/|
oo
m
<
m
o
or
o.io —•
23456
CONTAINERS AT THE COLLECTION STOP (NO.)
Figure D-l. General form of the Poisson distribution.
-------
Results are presented in Table D-4. Because a twice weekly
collection system must be sized for the "heavier" collection
day, the tabulation presents the probability values for con-
tainers on the first collection day of the week only.
The estimated crew times to service containers were derived
from time study data presented in reference 13 and tabulated
in Table D-5.
The container probability data and the container collection
time data were used to estimate the collection time per
stop for the various collection combinations. The collec-
tion time estimates are presented in Table D-6. In addi-
tion to container handling times/ the tabulated amounts
include travel time between stops on the route.
TABLE D-5
ESTIMATED AVERAGE COLLECTION
TIME (minutes)
Containers (no.)
Crew
size
1-man
2 -man
3-man
Pick-up
location
Curb
Curb
Curb
1
0.28
0.22
0.21
2
0.46
0.38
0.31
3
0.62
0.56
0.45
4
0.79
0.71
0.56
5 or
more
1.20
0.90
0.75
The average loading times per stop for separate collection
of newspaper were based on time studies of three-man sepa-
rate collection crews in Fort Worth, Texas10, in areas pro-
vided with both weekly and bi-weekly separate collection
service. These studies resulted in the following relation-
ship:
Newspaper
Loading
Time
= 0.05 + (0.004)
(average quantity
collected
per stop)
= min/stop
The resulting loading times for three-man crews were ad-
justed to derive analogous times for one and two-man crews
based on the ratios determined in the development of mixed
refuse loading times.
D-9
-------
TABLE D-4
STORAGE CONTAINER PROBABILITY PER COLLECTION STOP
D
1
Refuse Collected
Mixed refuse
Mixed refuse less newspaper
Mixed refuse
Mixed refuse less newspaper
Collection
Frequency
1/wk
1/wk
2/wk
2/wk
Probability/Containers
1 or
less 234
0.27 0.25 0.22 0.14
0.32 0.26 0.21 0.12
0.39 0.27 0.18 0.10
0.45 0.27 0.16 0.08
5 or
more
0.12
0.09
0.06
0.04
-------
TABLE D-6
ESTIMATED COLLECTION AND TRAVEL TIME PER STOP
Time Per Stop (min)
Collection Pick-up Crew Container Travel to
O
t
Refuse Collected
Combined refuse collection
Combined refuse
Combined refuse less newspaper
Combined refuse
Combined refuse less newspaper
Frequency
1/wk
1/wk
1/wk
1/wk
1/wk
1/wk
2/wk
2/wk
2/wk
2/wk
2/wk
2/wk
Point*
C
C
C
C
C
C
C
C
C
C
C
C
Size
1
2
3
1
2
3
1
2
3
1
2
3
Collection
0.56
0.49
0.40
0.54
0.46
0.38
0.48
0.41
0.34
0.46
0.40
0.32
Next Stop
0.20
0.20
0.20
0.20
0.20
,0.20
0.20
0.20
0.20
0.20
0.20
0.20
Tota
. 0.76
0.69
0.60
0.74
0.66
0.58
0.68
0.61
0.54
0.66
0.60
0.52
* C: Curb
-------
In addition to loading time, travel time between stops
varies with respect to participation rate, street frontage
per household, and collection methodology* among other var-
iables. Separate collection from the curb on one side of
the street at a time was assumed and travel time between
stops for separate collection simulated based on truck ac-
celeration to 10 mph between participating stops. The
results of this simulation are shown in Figure D-2 for
households with 40 ft and 100 ft street frontages at various
participation rates.# Figure D-2 was then used to estimate
travel time between stops at 20, 50, and 80 percent partici-
pation rates for an assumed street frontage of 50 ft per
residence. These estimated travel times were added to the
estimated loading times and recorded in Table D-2.
The average one-way driving time between the collection
route and the disposal site (B) for mixed refuse collection
trucks was assumed to be 15 min for typifying a short haul
situation and 45 min for a long haul situation. One-way
driving time between the collection route and the secondary
materials dealer was assumed to be 15 min to exemplify the
impact of separate collection when long haul of mixed refuse
is required.
The average time spent by the collection vehicle at the
disposal site or secondary materials dealer for emptying a
full load of mixed refuse or newspaper (D) was assumed to
be 15 min.
Non-productive time (K) for such functions as dispatch,
lunch and relief, yard to route time, and disposal site to
yard time was assumed to total 120 min per day.
Collection vehicles were allowed to return to the route
after collecting a full load of refuse or newspaper if at
least 25 percent of another full load could be collected
within the working day. No overtime was allowed.
*Collection methodology considers such variables as truck
type (side loader, rear loader), collection point (alley,
curb, on-property), collections made from one or both
sides of the street, etc.
#If two sides of the street collections are performed, the
same approach may be used although the probability of stop
is more complex than one side collection. Instead of
using a continuous 10-home segment, a 5-home segment is
used with homes on both sides of the street considered.
"Two-side" calculations, however, were beyond the scope of
this study and left to the reader.
D-12
-------
1.00
1.00
0.80
_, 0.70
CO
-P
3
e o.eo
XMI>
CO
C^
0
4J
W 0.50
(U
CD
3
0)
ffl 0.40
g
•H
F-i
^70 \
1 V6
\
1 \
. \ \
\ \
\ N
\
\
\
\
\40
\
\
EH
0.30 •
0.20
0.10
0.00
100 ft Frontage/
Household
40 ft Frontage/
Household
\:
10 20 30 40 50 60 70
Percent Participation
80 90
100
Figure D-2.: Average travel time between stops at
various participation rates.
D-13
-------
The additional time allocated for collection of a subsequent
full or partial load included 15 min to return to the col-
lection, area from the disposal site or secondary materials
dealer and another 15 min for driving time between the route
and the disposal site/dealer to dispose of the partial load.
Fifteen minutes were again allowed for disposing the partial
load.
Model Results
Although being too extensive to delineate each of the more
than 1,200 combinations resulting from the variables listed
in Table D-l, the printout accompanying this report can be
used as a tool to provide insight into the potential impact
of separate collection on overall solid waste collection
costs. As stated in the body of the report, if municipal
conditions are significantly different from those tabulated,
the model may be used to obtain applicable results by
inserting local variables and/or conditions. For example,
only curb pick-up of mixed refuse and separated newspaper
was evaluated. Municipalities providing on-property service
for mixed refuse should insert applicable information and
exercise the model rather than attempt use of the tabulated
data. Similarly, municipalities that estimate the average
weight of newspaper per household to significantly exceed
the 7 Ibs per week used in the model would again be advised
to exercise the model using applicable conditions. The
model is not extremely complex although time should be
taken to obtain applicable data if the model is to be used.
As a predictive tool, the model results will be as good as
the input data.
In order to exemplify the use and value of the model output/
six alternative collection situations were selected:
Crew Size~
Situation
No.
1
2
3
4
5
6
(no.
/vehicle)
Mixed Separate
3
3
1
3
3
1
3
2
1
3
2
1
Compactor
Type
{loading
location)
Rear
Rear
Side
Rear
Rear
Side
Vehicle
(cu yd)
20
20
20
20
20
20
Mixed
C •! 26
W .!> »|SS
Collection
Frequency
(no./wk)
1
1
1
2
2
2
D-14
-------
The first and fourth situations were selected to typify the
"average" municipal rase ;; tudy. Those parnmaters includod
use of three man crews for both mixed and separate collec-
tion from the curb with 20 cu yd rear-loading compactors.
Aside from changing mixed collection frequency, the only
modification in the parameters of the second and fifth
situations was reduction of separate collection crew size
from three to two. The third and sixth situations represent
minimization of crew size for both mixed and separate col-
lection. For the purpose of illustration, mixed refuse
collection frequency was fixed while separate collection
frequency was varied. Results are shown in Figures D-3
through D-8. Information is presented for separate collec-
tion frequencies of 1/wk, 1/2 wk and 1/mo. The dual set
curves for each collection frequency represent differences
due to long and short haul situations.* The tandem curves
shown for long and short haul situations represent the
difference in economic feasibility resulting from a change
in revenue from an average of $8/ton to an updated market
price of $25/ton. The respective bands at each revenue
rate represent the difference in diverted disposal cost
savings between a city operating its own landfill to a city
using a non-owned incinerator.
Separate collection is seen to have a more immediate impact
in long-haul situations due to reductions in long-haul of
mixed refuse. Similarly, savings attributed to quantities
diverted from incineration have a higher payoff than quan-
tities diverted from a landfill. Another logical consis-
tency is that once per month separate collection in conjunc-
tion with mixed collection represents the least cost
combination.#
The variation in curve shape is due to the effect that
revenue and disposal savings have on total collection costs
at various separate collection frequencies. In essence,
revenue and disposal savings have a dampening effect on
overall collection costs. In certain instances these
savings are not sufficient to dampen overall costs to a
point where an effective cost decline results. Cost is
*Long and short haul situations were depicted in the model
calculations by assuming respective one-way haul times of
15 min and 45 min.
#The effect of lesser quantities of recyclable materials
being placed out for collection as the 'collection frequency
is lengthened was determined after the model results were
documented.
D-15
-------
the most sensitive to collection frequency and labor, and
least sensitive to truck capacity (based on an assessment
of all capacities listed in Table D-l).
The importance of reducing separate collection crew size at
the once per week separate collection frequency is shown by
comparing Figures D-3 and D-4, and D-6 and D-7. Using the
combined refuse collection cost (designated on the Figures)
as a baseline situation, reduction of separate collection
crew size from 3 to 2 results in a breakeven situation
occurring with about 30 to 40 percent less participation at
the 1/wk separate collection frequency. Reducing crew size
at the 1/2 wk and 1/mo separate collection frequencies
resulted in breakeven situations occurring with 5 to 10 per-
cent less participation. This apparent decline in impact
is due to the relationship between quantity of newspaper
per stop and crew size (i,e. , at once per week a crew col-
lects 7 Ibs per stop; at bi-weekly or monthly frequencies,
the crew would respectively collect 14 or 30 Ibs, inherently
resulting in greater efficiency). Thus, economies of scale
are apparent.
The situations hypothesizing one-man collection situations
depict the least cost solutions for residential solid waste
collection prior to and after separate collection implemen-
tation. The effect of lessening costs in almost every
situation depicted in Figures D-5 and D-8 results from news-
paper revenue and diverted disposal savings being able to
overcome equipment and one-man labor costs at a faster rate
than if two or three times the labor is used to collect
identical quantities of waste (mixed or separate) when lar-
ger crews are used.
Regardless, the six illustrations typify the value of using
the model in local decision making. Without a costly trial
and error procedure, various service levels can easily be
hypothesized, breakeven situations assessed, and savings
and/or costs estimated.
D-16
-------
a
i
H
23r-
24
23
•o .
1 zz
«
« 2t
O
O
o
20
19
O
— - 18
o co
*• 5 i?
II '«
?»„
13
c o
O
O
12
10
o
£ 8
tu
r
e
l/wk Separate
Collection
Frequency
Paper market at time of case studies
(April 1973): f 8/ton
Assumed paper market: $Z5/ton
Diverted Incinerator Costs
Diverted Landfill Costs
1/2 wk Separate
Collection
Frequency
20 cu yd
3/3
l/wk
Combined Collection Cost for Long Haut
Combined Collection Cost for Short Haul
I/mo Separate
Collection
Frequency
10 20 30 40 SO 60 70 8O 90 IOO
10 20 30 40 50 60 70 BO 90 100
10 20 30 40 50 60 7O EO 90 100
PERCENT PARTICIPATION
Figure PHI, Imp act...of optimizing refuse collection operations: exemplary analysis,
3-man mlxe"d refuse collection performed once per week, 3 man separate collection crew.
-------
oo
01
TJ
o
jr
w
ui
3
O
X
2
O
§ •
m
o
o <
o in
o
o
UJ
Paper market at time of case studies
(April 1973 ): $8/ton.
Assumed paper market $25/ton
l/wk Separate
Collection
Frequency
_t i
t
j
Diverted Incinerator Costs
Diverted Landfill Costs
10 20 30. 40 SO 60 70 80 90 100
1/2 wk Separate
Collection
Frequency
_L
j_
j_
j I
20 cu yd
3/2
l/wk
Combined Collection Cost for Long Haul'-)
rn^~.. _ JL
Combined Collection Cost for Short HaulO
I/mo Separate
Cottsction
•Frequency
I i
i I
I
J t
10 20 30 40 90 60 70 80 90 100
PERCENT PARTICIPATION
10 20 30 40 50 60 70 60 90 100
Figure D-4. Impact of optimizing refuse collection operations: exemplary analysis,
3 man. mixed refuse collection performed once per,week, 2 man separate collection crew.
-------
O
VD
(A
•o
o
r
o
o
o
o"
23
24
23
22
21
20
19
- 18
IT
Is"
u 6 IS
^_ o 14
to z
O <
u «"
e o
•2* .2
u
= " II
O
° lOt
u
V
111
Paper market at time of case studies
(April 1973): $8/ton.
Assumed paper market $25/ ton
!/wk Separate
Collection
Frequency
1/2 wk Separate
Collection
Frequency
Diverted incinerator Costs
Diverted Landfill Costs
Combined Collection Cost for Short Hour
20 cu yd
I/I
I wk
I/mo Separata
Collection
Frequency
Combined Collection Cost for Long
10 20 10 40 90 60 70 80 90 100
10 20 SO 40 SO 60 70 80 90 100
J
10 20 30 40 90 60 70 80 90 100
PERCENT PARTICIPATION
Figure 'D . Impact of optimizing refuse collection operations: exemplary analysis,
1 man mixed refuse collection performed once per week, 1 man separate collection crew.
-------
o
I
T3
O
"S
o
o
o
-2532
•*= d
c o
o o
»- O 30
0>
a.
-------
O
I
40r-
39 -
3B-
in
1 "
O
O
O
35 -
2-33-
5 32
C O
O O
>- O 30
4?
0- V)
O 29
"" <
O ^ 28-
C O
•2 S 27
O
41
0)
£ 23
lij
2
l/wk Separate
Collection
Frequency
^^^*il? "??!•! ••
Paper market at time of case studies
(April 1973): $ 8/ton.
Assumed paper market: §25/ton
Diverted Incinerator Costs
Diverted Landfill Costs
1/2/wk Separate
Collection
Frequency
J .
20 cu yd
3/3
2/wk
Combined Collection
Cost for Long
I/mo Separate
Collection
Frequency
Combined Collection
Cost for Short Haul-j
I I
10 20 30 40 50 60 70 80 9O 100
10 20 30 40 SO 60 70 80 90 100
10 20 30 40 90 60 70 80 90 100
PERCENT PARTICIPATION
Figure 15-7. Impact of optimizing refuse collection operations: exemplary analysis,
3 man mixed refuse collection performed twice per week, 2 man separate collection crew.
-------
D
I
ro
NJ
Paper market at time of case studies
(April 1973): $8/ton.
£••:] Assumed paper market: $25/ ton
Diverted tnci nerator Costs
Diverted Landfill Costs
1/2 /wh Separate
Collection
Frequency
l/wk Separate
Collection
Frequency
20 cu yd
I/I
2/wk
Combined Collection Cost for Long
I/mo Separate
Collection
Frequency
Combined Collection Cost for Short Haul
i
i
i
i
I
i
10 20 30 40 90 60 70 60 90 JOO
10 20 30 40 90 60 70 60 90 100
10 ZO 90 40 30 CO 70 60 90 100
PERCENT PARTICIPATION
Figure D-a. Impact of optimizing refuse collection operations: exemplary analysis,
1 man mixed refuse collection performed twice per week, 1 man separate collection crew.
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APPENDIX E
RACK SYSTEMS ANALYSIS
The analysis to assess the economic impact of rack opera-
tions on a mixed refuse collection system incapable of
absorbing any incremental time is presented in this ap»-
pendix. The conceptual rack approach analyzed was modeled
after the Madison program: once per week collection of
mixed refuse and separated newspaper from the curb; a two
man crew; a lugger box transfer system for receipt of
newspaper from racks filled prior to the truck body filling
with mixed refuse; and 20 cu yd rear-loading compactors
with a single 0.9 cu yd rack mounted on the curb side of
the truck.
The analysis presented herein was performed using the
adapted collection model described in Appendix C.
Data Development
The data used to exercise the model are presented in Table
E-l and discussed in the ensuing text.
Collection vehicle capacity (V ) was limited to a 20 cu yd
compactor. The vehicle costs (Cv) were estimated to be $4
per hr ($0.067 per min). The two man crew based on nation-
al average labor rates12, had a total cost (Cc) of $0.174
per min, including fringe benefits.
The average compacted density of combined refuse (d) with
or without newspaper, was assumed at 650 Ibs per cu yd.
The average quantity of combined refuse per stop (Q) was
calculated based on 3.5 persons per residence and 2.5 Ibs
of solid waste generated per person per day. The resulting
average quantity of residential solid waste per stop was
estimated to be 61 Ibs per week. Assuming 7 Ibs of news-
paper per household per week, the remaining quantity of
combined refuse with all newspaper removed (100 percent
participation rate) was 54 Ibs. The quantity of combined
refuse per collection stop at the exemplary 20,40, and 60
percent participation rates was calculated assuming par-
ticipating stops generate 54 Ibs and non-participating
stops generate 61 Ibs of combined refuse on a weekly basis.
The average time per stop (t) for collection of mixed
refuse prior to separate collection of newspaper was es-
timated to be 0.49 min using a 2 man crew for once per
week collections.13 The time to collect mixed refuse less
E-l
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TABLE E-l
DATA FOR EXERCISING THE COLLECTION MODEL
-RACK APPROACH-
Mixed Refuse Rack Collection/
Variable Collection Only* Percent Participation4
vc
t
d
Q
B
D
K
Cv
Cc
(cu yd)
(min)
(Ib/cu yd)
(Ibs)
(min)
(min)
(min)
. ($/min)
($/min)
20
0.69
650
61.0
15
15.0
120
0.067
0.174
20
20
0.70
650
59.6
15
18.0
120
0.067
0.174
40
20
0.72
650
58.2
15
25.1
120
0.067
0.174
60
20
0.74
650
56.8
15
28.5
120
0.067
0 . 174
100
20
0.78
650
54.0
15
40.0
120
0.067
0.174
*Prior to implementation of separate collection.
+After implementation of separate collection.
E-2
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newspapers was estimated to be 0.45 min. Based on results
of a time study performed in San Francisco,15 the time re-
quired to load newspaper into a rack was determined to vary
with the rack fill rate. When empty, newspaper bundles
were randomly and rapidly tossed into the rack. When the
rack was half full (or more) some minor rearranging of
bundles was normally performed each time paper was added.
As the rack approached about 90 percent of capacity, ad-
ditional arranging was performed to provide for the last
few bundles. Assuming that bundled newspaper stacked in a
rack has a density of about 600 Ibs per cu yd (accounts for
stacking and bundling voids)/ a rack of 0.9 cu yd capacity
will hold the weekly newspaper generation from about 80
households at the assumed generation rate of 7 Ibs per
week.* Based on the time study and a fill rate of 80
households per rack, the handling times per newspaper
bundle are estimated in Table E-2.
TABLE E-2
NEWSPAPER LOADING TIME
-RACK APPROACH-
Rack Loading
Capacity* Time Time
(min/bundle) Applicability*
0-50 6 sec (0.10 min) first 40 stops
51-90 10 sec (0.17 min) next 32 stops
91-100 21 sec (0.23 min) last 8 stops
*Based on 80 stops to fill the rack.
The average time to proceed between collection stops on the
route was assumed to be 0.2 min. This time is assumed ade-
quate for stops ranging from 40 to 100 ft apart.
As would be expected, removing recyclable portions of mixed
refuse for separate collection increases the number of
*The number of households per rack is, of course, sensitive
to fluctuations in the generation rate. For example,
during.time studies conducted in San Francisco, a rack was
filled by newspaper from 30 households.
E-3
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households that can be served per "mixed truck load." Table
E-3 presents the number of households serviced per truck
load via the rack approach for each of the assumed partici-
pation rates. Based on participation rate, the number of
households placing newspaper out for separate collection is
also tabulated. The number of racks of newspaper filled per
truck load is shown based on the factor of 80 stops per
rack.
TABLE E-3
RACK FILL RATE VERSUS PARTICIPATION
-20 CU YD TRUCK-
Participation
Rate
Households
Per Load,
Q
(no.)
Households
Participating
(no.)
Newspaper
Racks Filled
Per Load
(no.)
0
(mixed refuse
coll'n only)
213
20
40
60
100
218
223
229
241
44
89
137
241
0.6
1.1
1.7
3.0
Using the number of participating households from Table E-3/
the rack fill rate, and the estimated newspaper handling
times in Table E-2, the average time per collection stop
for rack operations was calculated at the various partici-
pation levels as follows:
(In2 )
{SJ -
(t
m
(t -n) + (t )
-------
Where:
tj = average time per collection stop at partici-
pation rate j (min)
S. = number of collection stops per load at par-
•J ticipation rate j (households)
P.: = number of participating households at par-
ticipation rate j (households)
= average time per collection stop for mixed
refuse (min)
tmr"n = average time per collection stop for mixed
refuse with newspaper removed (min)
= number of households placing out newspaper
bundles contributing to the first 50 percent
of rack load i at participation rate j
(bundles)
n.2 ~ number of households placing out newspaper
i bundles contributing from 51 to 90 percent
of rack load i at participation rate j
(bundles)
n3. = number of households placing out newspaper
1 bundles contributing from 91 to 100 percent
of rack load i at participation rate j
(bundles)
tn< = average time to load newspaper bundles con-
i tributing to the initial 50 percent of a
rack load (min/bundle)
tn = average time to load newspaper bundles con-
2 tributing to 51 to 90 percent of a rack load
(min/bundle)
t = average time to load newspaper bundles con-
n3 tributing to 91 to 100 percent of a rack
load (min/bundle)
t = average travel time between stops on the
ns route (min)
E-5
-------
Exercising the preceding equation with participation per-
centages of 20, 40, 60, and 100 yielded average collection
times per stop of 0.70 min, 0.72 min, 0.74 min, and 0.78
min, respectively.
The average one-way driving time between the collection
route and the disposal site (B) was assumed to average 15
minutes for the exemplary analysis (i.e., short haul).
The average time spent by the collection vehicle at the
disposal site for emptying a full load of mixed refuse (D)
was assumed to be 15 min.
Additional time must be included in the disposal time for
varying levels of participation associated with rack opera-
tions. The number of times a rack would fill while collect-
ing one full load was shown in Table E-3. Based ontthe
fill rate, the number of times that the collection vehicle
and crew would be required to leave the collection route to
transfer newspapers is presented below:
Participation Newspaper Racks Trips Required for
Rate Filled Per Load Newspaper Transfer
(%) (no.) (no.)
0 0 0
(mixed
coll'n)
20 0.6 0
40 1.1 1
60 1.7 1
100 3.0 2
As previously stated, a newspaper transfer operation using
lugger boxes was assumed. Lugger boxes are prepositioned
each day in the collection area to minimize the off*route
haul time. The average round-trip in Madison was about 2
miles and required about 5 min of driving time per transfer.
Transfer of newspaper from the rack to the lugger box re-
quired an average of 5 min. In addition, the paper rack
is unloaded each time the collection vehicle makes a trip
to the disposal site. (A lugger box was located at the
disposal site for this purpose.) Off-loading time at the
disposal site was assumed to be proportional to the amount
of newspaper in the rack at the time a full load of mixed
refuse was attained. Thus, the times shown in Table E-4
were estimated for dumping operations.
E-6
-------
M
TABLE E-4
ESTIMATED DUMPING TIME: RACK OPERATIONS
Participation
Rate
0
iMixed
coll'n)
20
40
60
100
Trips Required
to Transfer
(no.)
0
0
1
1
2
Time
Travel
0
0
5
5
10
for Transfer
(min.)
Off Loading
Newspaper
0
0
5
5
10
Time to Empty
Rack at
Disposal
Site
(min . )
0
3.0
0.1
3.5
5.0
Dumping
Time for
Mixed
Refuse
(min. )
15
15
15
15
15
Total
Dump
Time
(min. )
15.0
18.0
25.1
28.5
40.0
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Non-productive time (K) for such functions as dispatch,
lunch and relief, yard to route time, and disposal site to
yard time was assumed to total 120 min per day.
Collection vehicles were allowed to return to the route af-
ter collecting a full load of refuse if at least 25 percent
of another full load could be collected within the working
day. No overtime was allowed.
The additional time allocated for collection of a subsequent
full or partial load included 15 min to return to the col-
lection area from the disposal site and another 15 min for
driving time between the route and the disposal site to
dispose of the partial load. Fifteen minutes were again
allowed for disposing the partial load.
Impact on Normal Refuse Collection
The collection model was exercised using the data developed
above to estimate the total cost of collection operations
with and without separate collection via the rack approach.
Due to incremental time requirements for newspaper handling,
crews employing the rack method were not capable of serving
the same number of households as normal collection crews.
Thus, collection costs were increased. However, revenue
derived from the sale of separately collected newspaper and
from diverted disposal defrays the added collection cost.
Also to be considered in the analysis are the costs for
labor and equipment used for collecting the lugger boxes
used on the routes for interim paper storage, transporting,
dumping, and replacing the boxes on the route for use on the
following day. The cost of handling lugger boxes on the
collection route was only applicable to the example situa-
tion when participation rates exceeded about 35 percent.
Lower participation did not require transfer on route as the
capacity of the rack was not exceeded during the collection
of a full load of refuse. As such, the newspapers were
unloaded only at the disposal site prior to dumping the
collected refuse.
Based on the case studies, the transfer container for news-
paper at the disposal site and subsequent transport was
generally provided by the paper stock dealer. Therefore,
no costs were assigned to rack operations for these activi-
ties.
For participation rates exceeding 35 percent, lugger boxes
were required for interim storage. From two to six man-
E-8
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hours were required daily in Madison for collecing trans-
ferred newspapers from four lugger box containers and
prepositioning the containers for the next days operations.
Assuming four man-hrs per day as an average and a cost of
$5.80 per man-hr (the rate of a collection vehicle driver
including fringe benefits), the monthly labor costs were
estimated to be:
Labor cost = 4 hr x $5.80 x 21 days = $4 90/mo
day hr mo
Equipment requirements were based on the assumption that a
hoist truck with a 6,000 Ib lift capacity and four 10 cu yd
lugger boxes would be required for a rack program with over
35 percent participation. Assuming a 6 yr economic life,
an initial cost of $9,000, and $1,000 per year operating and
maintenance costs, the hoist truck costs were estimated to
be:
Hoist
truck = $l,500/yr depreciation + $l,000/yr O & M = $210/mo
cost 12 mo/yr
Lugger boxes were estimated to cost about $35 per mo assuming
four 10 cu yd boxes with an initial cost of $550 each, an
economic life of 10 yrs, and maintenance costs equalling
initial costs over the 10-yr period.
Container _ 4 ($550 depreciation + $550 maintenance)„ $35/mo
costs 10 yrs x 12 mo/yr
Therefore, the fully allocated cost to preposition and
unload lugger boxes was estimated to total $735 per month.
Of this sum only equipment operational and maintenance costs
amounting to $100 per mo were considered incremental. The
hoist truck and lugger boxes were assumed to have been part
of the solid waste management equipment inventory prior to
implementation so that depreciation costs were not consid-
ered incremental. Labor to preposition and collect the
lugger boxes in Madison is provided by four collection crew-
men (loaders that would normally ride to and from the route)
and, therefore, also not incremental.
Revenue for newspapers averaged $8 per ton at the time of
case study. An updated revenue of $25 per ton was assumed
to be more representative of current market prices.
Disposal savings, as developed in Appendix B, were estimated
as follows:
E-9
-------
Disposal Savings
Disposal Method ($/ton)
Sanitary landfill
First-party ownership 0.80
Second-party ownership 2.50
Incineration
First-party ownership 5.35
Second-party ownership 10.50
Based on the preceding discussion and estimates, the effec-
tive rack collection costs per mo for a hypothetical city
of 10,000 households is displayed in Figure E-l reflecting
revenue and the extremes of possible disposal cost savings.
Also plotted for comparative purposes .is the estimated
baseline cost for mixed refuse collection prior to imple-
mentation of the rack separate collection sub-system (desig-
nated "combined refuse collection cost"). The discontinui-
ties shown delineate points where off-route transfer of
newspaper are required. At these points (35 and 70 percent
participation), a quantum increase in cost is incurred by
a collection system unable to absorb incremental time.
Curves reflecting revenue at $8 per ton show savings ex-
ceeding collection cost only under the circumstances of less
than 35 percent participation and second party incinerator
disposal savings.
The economic projections with revenue at $25 per ton are
more favorable. When participation is less than 35 percent,
incremental collection costs are recovered. Incremental
costs betwoen 35 and 70 percent were at, or below, a break-
even situation, while only savings attributed to diverted
incinerator disposal were able to effectively decrease col-
lection costs beyond participation of 70 percent.
The exemplary results shown in Figure E-l depicted a short
haul situation. Changing only the one-way driving time
variable (B) in Table E-l from 15 min to 45 min to portray
a long-haul situation resulted in Figure E-2.
The discontinuity at 20 percent participation in the long-
haul relationship represents the point where incremental
time requiarements become so severe that collection trucks
are unable to collect more than one full -load per day,
(i.e., there is not sufficient time for a truck to return to
the route for a second or partial load). Economic feasi-
bility in the long-haul example is indicated only at
E-10
-------
CO
•O
•H
O
X
(U
(0
3
O
w
O
O
O
^
O
rH
O CO
M-l H
-P H
C O
o-o
0)
(0
** s
10 ra
O CO
U 3
O
•H
-P
O
0)
O
tj
•H
-P
O
0)
17
16
15
14
13
12
11
10
,
!•••*<
• •••I
• •••I
Paper market at time of
case studies (April 1973) :
$8/ton.
Assumed paper market:
$25/ton.
••••••••••••••••••••t
••••••••••••••••••••I
Combined
Refuse
Collection
Cost
j/Points where. |
poff-route y
transfer of
newspaper is
required
10 20 30 40 50 60 70
Percent Participation
80 90
100
Figure E-l. Effective.cost for rack collection of separated
newspaper versus combined refuse collection cost prior to
system implementation: exemplary analysis for short haul
situation.
-------
22
to
O
x:
CD
en
o
o
o
O W
a
$3
c o
O "O
IH
M O
ft cn
co ra
O en
o =>
o
+J
O
8
•H
•P
O
O
21
20
19
18
17
16
15
•Point where incremental
time requirements prevent^
crew from returning to
collection route for second
(or partial) load.
Combined
Refuse
Collection
Cost
Paper market at time of
•case studies (April 1973): $8/ton
Assumed paper market: $25/ton
0 10 20 30 40 50 60 70 80
Percent Participation
4-
90 100
Figure E--2. Effective cost for rack collection of
separated newspaper versus combined refuse collection
cost prior to.system implementation: exemplary analysis
for long haul situation. -
E-12
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participation rates less than 20 percent and some situations
exceeding 70 percent participation in conjunction with $25
per ton revenue.
E-13
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