Residential Solid Waste
Generated In
Low-income Areas
I
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A Study of Residential Solid Waste
Generated in Low-income Areas
This report (SW-83ts) was written by
GEORGE R. DAVIDSON, JR.
U.S. ENVIRONMENTAL PROTECTION AGENCY
1972
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An environmental protection publication
in the solid waste management series (SW-83ts)
Single copies of this publication are available from solid
waste management publications distribution unit, U.S. Environmental
Protection Agency, Cincinnati, Ohio 45268.
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FOREWORD
Variations inherent in the generation of solid wastes
make it extremely difficult to predict quantities that can
be expected from a dwelling within a residential neighbor-
hood. Some possibly influencing factors are climate,
season, socioeconomic level, and dweller density.
The objective of this study was to examine the quantities
and critical factors involved in the generation of solid
wastes in low-income residential neighborhoods. The results
are presented in order that a better understanding of waste
quantities and characteristics may be obtained. The quan-
tities reported may be used in conjunction with studies of
similar areas to provide improved estimates of solid waste
generation rates.
--SAMUEL HALE, JR.
Deputy Assistant Administrator
for Solid Waste Management
i i i
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A Study of Residential Solid Waste
Generated in Low-income Areas
This study of solid waste generation characteristics was
conducted during a four-week period over three collection
routes in a low-income area of Cincinnati, Ohio to determine
the quantities and critical factors involved in solid waste
generation. It was assumed that there was no significant
variation among the routes in the solid waste they generated
and that, if combined, they would represent a typical low-
income area with respect to waste generation. Testing of
this assumption showed that combining the routes was valid.
Five variables that characterize the solid waste gen-
erated in this area were studied: pounds and gallons per
sample point per week; pounds and gallons per capita per
week; and, pounds per cubic yard. (Preliminary analysis
indicated that the first two would be of little use in esti-
mating waste generation because the quantities varied too
greatly.)
A random sampling of houses was not made. Instead
dwellings judged to be representative were studied, and the
data collected were treated as if they had been acquired
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from a random sampling. Solid waste from 15 residences on
each route was collected and separated during the second
week to determine its composition.
The following are average values for each dwelling type
studied:
Single family Multifamily Apartment
dwelling dwel1i ng house
Pounds/capita/week 12.54 9.83 6.91
Gallons/capita/week 14.07 11.00 5-61
Pounds/cubic/yard 179-97 180.50 248.87
Analysis indicates that:
1. The average solid waste contribution per person is
constant within each of the dwelling classifications studied
(multifamily, single-family, and apartments).
2. A fixed amount of solid waste (junk mail, lawn trim-
mings, etc.) is generated per dwelling regardless of the
number of persons occupying it.
3. The total quantity of solid waste generated from a
dwelling depends on the number of occupants, not the dwelling
type.
4. Making comparisons of solid waste generation on a
per capita basis alone may be misleading.
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FIELD METHODOLOGY
Data Col lection
After discussions were held with the Cincinnati Com-
munity Action Commission, three routes within an area bounded
by Vine Street and Forest, Gilbert, and Dorchester Avenues
were chosen for study. Statistics furnished by the U.S.
Census Bureau indicated that they served a low-income area.
An effort was made to use each dwelling on the three routes
as a sample point. In all, 96 single family residences, 137
multifamily residences, and 6 apartment houses were studied
for three consecutive weeks, and data regarding these dwell-
ings were considered in the analysis.
Each of the routes selected could be observed on a
different day of the week. This was convenient since the
city provides once-a-week waste collection, and each route
could be sampled in its entirety on one day.
Two study groups (each equipped with scales) were used
to record data. Because the city trucks follow a strict
schedule, the collection of data had to be adjusted so that
the sanitation workers were not to be delayed.
After trial data collection runs were made over each
route, formal data collection was begun. A 5~man forward
crew, a truck driver, a data recorder, and three men who
weighed the solid waste preceded the city collection truck
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and two men who followed it weighed the empty containers.
The forward crew also estimated the volume of the waste;
both crews recorded the address of the dwelling whose occu-
pants had generated it.
The cans were weighed to the nearest one-half pound on
platform scales. Loose waste was placed in a 50-gallon carry
can to be weighed and to have its volume estimated. Bulky
items such as furniture, stoves, refrigerators, and washing
machines were not considered. Estimates of solid waste
volume were reported as full or half-full 10-, 20-, and
30-gallon cans. This sacrifice in accuracy was necessary
so that the forward crew could remain ahead of the city
truck.
The compositon of the solid waste was determined by
manually separating samples collected during the second week
of the study. From a table of 200 random numbers, 15 numbers
were selected for each route. These numbers were noted by
an asterisk on the numbered cards that were placed with groups
of full waste containers. (The numbered index cards were
used to correlate the weights of the full and empty sets of
containers.) As the forward crew encountered a card contain-
ing an asterisk, it weighed the full containers, emptied the
contents into plastic bags, and put identification tags on
them. The bags were put in the rear of the scale truck and
were later taken to the city garage where they were manually
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separated into nine classes: paper products; food wastes;
garden wastes; plastics, rubber, and leather; textiles;
wood; metals; glass and ceramics; and ash, rocks, and dirt.
All of the bags from each dwelling were treated as a single
sample.
A door-to-door survey was carried out during the fourth
week of the study to determine how many people lived in
each dwelling. This information was used to obtain per
capita generation rates.
Route Characteristics
In an attempt to characterize the routes, the Hamilton
County Tax Office and Cincinnati Community Action Commission
were contacted. Characteristics obtained included informa-
tion about the occupants and the condition of their dwellings.
Only information about single and multifamily dwellings was
available (Tables 1 and 2). The data indicate that such
dwellings were similar with respect to value and condition
on al1 three routes.
Information was also gathered on the occupants of all
dwellings for each route according to education, employment
status, and total income (Table 3). The occupants of dwell-
ings on route A had slightly higher levels of income, educa-
tion, and employment than persons living on the other routes.
Data were also gathered during a door-to-door survey (Table k)
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TABLE 1
CHARACTERISTICS OF SINGLE-FAMILY DWELLINGS SAMPLED'
Route
A
B
C
Dwel 1 i
val ue
$1,960
2,260
1,400
. , Dwellings 50 Wooden frame
ng Land 3
+ , + years or older construction
T value1 / ,.\ / \
(percent) (percent)
$9,480
8,020
5,260
68
79
68
"Based on 1962 Cincinnati tax assessment.
"^Median value based on total number of dwell
TVery bad condition; major repairs needed.
Route
A
B
C
Owe 11 i
value
$2,840
1,980
1,420
CHARACTER! STI
TABLE 2
CS OF MULTIFAMI
41
68
65
ings for
LY DWELL
. , Dwellings 50 Wooden frame
+ , + years or older construction
1 value1 / ^\ / v
(percent) (percent)
$12,140
8,900
7,080
52
75
61
45
37
70
Dwel 1 i ngs wi th
front footage of
lot < 40 feet
(percent)
50
59
85
each route.
INGS SAMPLED-1'
Dwel 1 i ngs wi th
front footage of
lot <_ 40 feet
(percent)
42
63
70
Dwel 1 i ngs i n
di lapidated
condi t ionr
(percent)
15.9
14.8
16.9
Dwel 1 i ngs in
di lapidated
condi tionf
(percent)
15.9
14.8
16.9
"Based on 1962 Cincinnati tax assessment.
"^Median value based on total number of dwellings for each route,
TVery bad condition; major repairs needed.
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Information presented in these four tables indicates that
the routes studied were similar with respect to dwelling and
occupant characteristics.
TABLE 3
CHARACTERISTICS OF OCCUPANTS
OF ALL DWELLINGS FOR EACH ROUTE*
(Percentages)
Route
A
B
C
Heads of
household wi th
< 10th grade
educati on
31.7
46.4
46.5
Heads of
household
unemployed
31-7
44.4
40.8
Fami 1 ies
with income
< $3,600
23.8
40.8
39.6
"Statistics furnished by Cincinnati Community Action
Commi ss i on.
TABLE 4
DWELLER DENSITY'1-
Dwel 1 i ng type
Single family dwellings
Multifamily dwellings
Apartment houses
Route
A
B
C
A
B
C
A
Contributors per
sample point
(average)
4.0
4.4
4.5
10.6
8.0
6.5
50.3
(range)
1-9
1-12
1-11
4-21
2-26
3-14
17-126
-Derived from door-to-door survey.
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Data Analysis
The solid waste collected during the second week was
separated to determine its characteristics (Table 5).
TABLE 5
RESULTS OF SOLID WASTE SEPARATION
r_t Percent of component (wet weight basis)*
Food
Paper
Plastics, rubber,
leather
Texti les
Wood
Metal
Glass, ceramics
Ash, rocks, and dirt
Garden
Route A
22.70
40.77
2.81
1.11
0.28
8.43
13.12
5.03
5.66
Route B
22.06
46.39
1.64
3.03
0.12
8.39
11.26
6.86
0.28
Route C
27.19
34.38
2.80
1.85
0.67
10.19
14.50
5.44
2.95
"Average values obtained from 15 random samples per
route.
The results were then compared to findings derived from
a year-long study that had been made earlier of solid wastes
generated in low-income areas of Jefferson County, Kentucky.
The solid waste collected there, however, had been separated
into only five categories; paper (all combustibles except
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food wastes); garbage (food wastes); metals; minerals (ash,
rocks, and dirt); glass (including ceramics). When the
Cincinnati separation results were converted to these five
categories, the results from both areas were similar (Table
6).
TABLE 6
SOLID WASTE CHARACTERISTICS BY AREA
Category
Paper
Garbage
Metals
Mi nerals
Glass
Percent of
component (wet weight basis)
Cincinnati" Jefferson County
48.2
23-9
9.0
5.7
12.9
56.4
20.5
10.6
1.1
11.2
"Result of combining routes for each component.
A summary of the means and standard deviations for each
of the three quantities studied over the three-week period
was formulated (Table 7)•
These data indicate that waste generated by any given
residence varied widely from week to week. Within any dwell-
ing classification, however, there was a consistent relation-
ship between the weekly per capita generation rate and the
number of people in the dwelling type. It decreased as the
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TABLE 7
SYNOPSIS OF STATISTICAL INFORMATION
PCW
Type
en
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TO
LJ_
en
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CO
en
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TO
4-1
1/1
4-J
0)
E
4-1
03
Q.
Route Week
1
2
A 3
Comb ined
1
2
B 3
Combi ned
1
2
C 3
Combi ned
1
2
A 3
Comb i ned
1
2
B 3
Combi ned
1
2
C 3
Comb i ned
1
2
A 3
Comb i ned
Mean
15.13
18.31
14.78
16.07
12.43
12.60
10.05
11.69
10.94
11.83
11.75
11.51
9.71
9.00
8.61
9.11
9.98
10.04
10.84
10.29
9.07
9.87
10.77
9.91
5.46
5.95
9.33
6.91
Standard
deviation
2.09
2.80
1.97
1.32
1.32
1.85
0.93
0.82
1.29
1.35
1.20
0.73
1.00
0.94
0.96
0.56
0.86
0.87
1.09
0.54
0.91
0.87
1.04
0.54
1.24
1.00
1.57
1.01
GCW
Mean
17.81
17.93
16.29
17.34
14.36
14.33
11.34
13.34
13.13
13.96
12.12
13.07
10.76
9.91
9.86
10.18
12.85
11.50
11.25
11.87
10.66
10.65
10.28
10.53
4.97
6.16
5.70
5.61
Standard
deviation
2.23
2.45
2.03
1.28
1.39
2.04
1.13
0.96
1.36
1.53
1.28
0.81
0.99
0.95
1.14
0.60
1.11
0.92
0.96
0.62
1.20
0.85
0.95
0.58
1.19
1.92
1.39
0.88
Mean
171.63
206.20
183.16
187.15
174.73
177.65
178.96
176.97
168.20
171.23
195.83
177.82
182.31
183.50
176.29
1 80 . 75
156.88
176.34
194.54
175.07
171.89
187.21
211.65
189.99
221.82
195.01
330.71
248.87
PCY
Standard
deviation
15.10
21.55
12.79
9.88
9.68
13.84
13.79
9.21
10.09
10.60
10.06
6.08
11.77
10.24
10.03
6.19
5.34
8.19
7.53
4.41
8.26
8.70
9.72
5.45
15.77
47.90
94.39
40.94
"Sampled on Route A only.
10
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PEOPLE PER DWELLING
Figure 3. Solid waste generation from apartment houses.
120
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©SINGLE FAMILY DWELLINGS
A MULTI- FAMILY DWELLINGS
PAPARTMENT HOUSES
10
20
30
40
50
PEOPLE PER DWELLING
60
Figure 4. Solid waste generation from single family, rnulti- family and
apartment houses.
i
126
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number of people increased (Figures 1 to 3) but became
asymptomatic (constant) to a value of 6 pounds after a
value of 15 people per dwelling was reached (Figure 4). The
explanation for this may be in the relationship established
between average total waste generation per sample point and
the number of people per dwelling for all dwelling types
(Figure 5). A single family home with two people in it,
for example, generated an average of approximately 33
pounds per week. The fact that the trend line begins at
a point greater than zero indicates that the dwelling unit
and its grounds contributed to the solid waste stream.
ACKNOWLEDGMENTS
The Division of Technical Operations thanks Thomas P.
Welch, Superintendent of the Division of Waste Collection,
Cincinnati, Ohio, and his staff for their cooperation during
the field study.
Help provided by personnel of the Division of Technical
Operations in the preparation of this report is gratefully
acknowledged. In particular, the author wishes to thank
Martha Madison for her assistance in data analysis and
Robert Clark and Claude Schleyer for their guidance in pre-
paring the final report.
13
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OSINGLE FAMILY DWELLINGS
' A MULTI-FAMILY DWELLINGS
Q APARTMENT HOUSES
A
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10
20
30
40
50
60
126
PEOPLE PER DWELLING
Figures. Solid waste generation from single family, multi- family and
apartment houses.
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