United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
(5305W)
EPA530-S-98-007
May 1998
www.epa.gov/osw
vvEPA
Characterization of
Municipal Solid Waste in
jf
The United States:
1997 Update
Executive Summary
-------
-------
CHARACTERIZATION OF
MUNICIPAL SOLID WASTE
IN THE UNITED STATES:
1997 UPDATE
EXECUTIVE SUMMARY
Prepared for
U.S. Environmental Protection Agency
Municipal and Industrial Solid Waste Division
Office of Solid Waste
Report No. EPA530-S-98-007
by
Franklin Associates, Ltd.
Prairie Village, KS
May, 1998
Printed on recycled paper
-------
-------
CHARACTERIZATION OF MUNICIPAL SOLID WASTE
IN THE UNITED STATES: 1997 UPDATE
Executive Summary
FEATURES OF THIS REPORT
This report is the latest in a series of reports published by the U.S.
Environmental Protection Agency (EPA) describing the national municipal solid
waste (MSW) stream. The report characterizes the national solid waste stream for
1996. It also discusses trends and highlights changes that have occurred over the
years, both in the types of wastes generated and in the ways they are managed.
Although the report does not specifically address local and regional variations in
the waste stream, the data in the report can be used to develop approximate
estimates of MSW generation and composition in defined areas.
This report includes information on:
• Total MSW generation, recovery, and discards from 1960 to
1996.
• Per capita generation and discard rates.
• Materials (e.g., paper, glass, metals, plastic) that comprise
MSW, as well as products (e.g., durable and nondurable goods,
containers, packaging) found in the waste stream.
• Aggregate data on the infrastructure for MSW management,
including estimates of the number of curbside recycling
programs, drop-off centers, materials recovery facilities, and
composting programs in the United States.
• Trends in MSW management from 1960 to 1996, including
source reduction, recovery for recycling (including
composting), and disposal via combustion and landfilling.
• Markets for major recovered materials (paper and paperboard,
container glass, aluminum cans, steel in cans and appliances,
PET and HDPE plastics, and compost).
-------
REPORT HIGHLIGHTS
1996 MSW Generation and Management:
• A total of 209.7 million tons of MSW was generated in 1996.
This reflects a decrease of nearly 2 million tons from 1995,
when MSW generation was 211.5 million tons.
• The per capita generation rate in 1996 was 4.3 pounds per
person per day, compared to 4.4 pounds per person per day
in 1995.
• The per capita discard rate (after recovery for recycling,
including composting) was 3.2 pounds per person per day in
1996, down from 3.3 pounds per person per day in 1995.
• Recycling (including composting) recovered 27 percent (57
million tons) of MSW in 1996, up from 26 percent (55
million tons) in 1995.*
• There were nearly 9,000 curbside recycling programs in the
United States in 1996, as well as more than 10,000 drop-off
centers for recyclables. About 360 materials recovery
facilities helped process the recyclables collected. More than
3,000 yard trimmings composting programs were reported.
• Recovery of paper and paperboard reached 41 percent (33
million tons) in 1996, accounting for more than half of the
total MSW recovered. In addition, nearly 11 million tons of
yard trimmings were recovered for composting in 1996,
accounting for the second largest fraction of total recovery.
The percentage of yard trimmings composted (38 percent)
has more than doubled since 1992.
• Landfills managed 55 percent of MSW generated (116
million tons), down from 57 percent in 1995. Combustion
facilities managed 17 percent (36 million tons) of total MSW
generated, about the same as in 1995.
Data shown for years prior to 1996 have been adjusted to reflect the latest revisions to the
methodology and therefore may differ slightly from the same measure reported in previous
updates.
-------
DEFINITIONS AND METHODOLOGY
Municipal solid waste ( MSW) includes wastes such as durable goods, nondurable goods,
containers and packaging, food scraps, yard trimmings, and miscellaneous inorganic wastes from
residential, commercial, institutional, and industrial sources. Examples of waste from these
categories include appliances, automobile tires, newspapers, clothing, boxes, disposable
tableware, office and classroom paper, wood pallets, and cafeteria wastes. MSW does not include
wastes from other sources, such as construction and demolition debris, automobile bodies,
municipal sludges, combustion ash, and industrial process wastes that might also be disposed in
municipal waste landfills or incinerators.
Source reduction activities reduce the amount or toxicity of wastes before they enter the
municipal solid waste management system (see Generation). Reuse is a source reduction activity
involving the recovery or reapplication of a package, used product, or material in a manner that
retains its original form or identity. Reuse of products such as refillable glass bottles, reusable
plastic food storage containers, or refurbished wood pallets are examples of source reduction.
Generation refers to the amount (weight or volume) of materials and products that enter the
waste stream before recycling (including composting), landfilling, or combustion takes place.
Recovery of materials means removing MSW from the waste stream for the purpose of recycling
(including composting). Recovery for recycling as defined for this report includes purchases of
postconsumer recovered materials plus net exports of the materials. Recovery of yard trimmings
includes diverting yard trimmings from disposal to a composting facility. For some materials,
recovery for uses such as highway construction or insulation is considered recovery along with
materials used in remanufacturing processes.
Combustion includes combustion of mixed MSW, fuel prepared from MSW, or a separated
component of MSW (such as rubber tires) , with or without energy recovery.
Discards include the municipal solid waste remaining after recycling (including composting).
These discards are usually combusted or disposed of in landfills, although some MSW is littered,
stored, or disposed on site, particularly in rural areas.
Methodology. There are two primary methods for conducting a waste characterization study. The
first is a source-specific approach in which the individual components of the waste stream are
sampled, sorted, and weighed. Although this method is useful for defining a local waste stream,
extrapolating from a limited number of studies can produce a skewed or misleading picture if used
for a nationwide characterization of waste. Atypical circumstances encountered during sampling
or errors in the sample would be greatly magnified when expanded to represent the nation's entire
waste stream. The second method, which is used in this report, is called the "material flows
methodology." EPA's Office of Solid Waste and its predecessors in the Public Health Service
sponsored work in the 1960s and early 1970s to develop the material flows methodology. This
methodology is based on production data (by weight) for the materials and products in the waste
stream, with adjustments for imports, exports, and product lifetimes.
-------
MUNICIPAL SOLID WASTE IN 1996
MSW consists of both materials and products. Materials in MSW include
paper and paperboard, yard trimmings, glass, metal, plastics, wood, and food
wastes. Each material category (except for food wastes and yard trimmings) is
made up of many different products. Products in MSW are grouped into three
main categories: (1) durable goods (e.g., appliances), (2) nondurable goods (e.g.,
newspapers), and (3) containers and packaging. These product categories
generally contain each type of MSW material, with some exceptions. The durable
goods category contains no paper and paperboard. The nondurable goods category
includes only small amounts of metals and essentially no glass or wood. The
containers and packaging category includes only very small amounts of rubber,
leather, and textiles.
Materials in MSW
In 1996, MSW generation totaled 209.7 million tons. Figure ES-1 provides
a breakdown, by weight, of the MSW materials generated in 1996. Paper and
paperboard products made up the largest component of MSW generated (38
percent), and yard trimmings comprised the second largest material component
(13 percent). Glass, metals, plastics, wood, and food wastes each constituted
Figure ES-1. Materials generated In MSW by weight, 1996
(Total weight = 209.7 million tons)
Glass 5.9%
12.4 million tons
Metals 7.7%
16.1 million tons
Paper & paperboard 38.1%
79.9 million tons
Plastics 9.4%
19.8 million tons
Wood 5.2%
10.8 million tons
Food 10.4%
21.9 million tons
Yard trimmings 13.4'
28.0 million tons
Other 9.9%
20.8 million tons
-------
between 5 and 10 percent of the total MSW generated. Other materials in MSW,
such as rubber, leather, textiles, and miscellaneous wastes, made up
approximately 10 percent of the MSW generated in 1996.
A portion of each material category in MSW was recycled or composted in
1996, as illustrated .in Table ES-1. It should be noted, however, that recovery rates
for some products within a material category are higher than the overall
recovery rate for the material category, because some products are not
Table ES-1
GENERATION AND RECOVERY OF MATERIALS IN MSW, 1996
(In millions of tons and percent of generation of each material)
Paper and paperboard
Glass
Metals
Ferrous metals
Aluminum
Other nonferrous metals
Total metals
Plastics
Rubber and Leather
Textiles
Wood
Other materials
Total Materials in Products
Other Wastes
Food Wastes
Yard Trimmings
Miscellaneous Inorganic Wastes
Total Other Wastes
TOTAL MUNICIPAL SOLID WASTE
Weight
Generated
79.9
12.4
11.8
3.0
1.3
16.1
19.8
6.2
7.7
10.8
3.7
156.6
21.9
28.0
3.2
53.1
209.7
Weight
Recovered
32.6
3.2
4.5
1.0
0.8
6.4
1.1
0.6
1.0
0.5
0.8
46.0
0.5
10.8
Neg.
11.3
57.3
Recovery
as a Percent
of Generation
40.8%
25.7%
38.0%
34.3%
66.8%
39.6%
5.3%
9.5%
12.3%
4.5%
21.2%
29.4%
2.4%
38.6%
Neg.
21.3%
27.3%
Includes wastes from residential, commercial, and institutional sources.
Neg. = Less than 50,000 tons or 0.05 percent.
-------
recovered at all. For example, aluminum cans are recovered at rates above 60
percent, but the overall recovery rate for aluminum is 34 percent. Likewise, even
though corrugated containers are recovered at a rate of nearly 67 percent, the
overall recovery rate for paper and paperboard is 41 percent.
For this Update, significant changes were made in the methodologies and
data sources for wood and food wastes. These changes, which were incorporated
into revised estimates for 1990 through 1995, result in an increase in the
estimated total amount of MSW generation previously published. (See Chapter 2
for discussions of these changes.) Because of the increases in generated tonnage,
revised total recovery percentages for the years 1990 through 1995 declined
slightly.
Products in MSW
Figure ES-2 shows the breakdown, by weight, of MSW products generated
in 1996. Containers and packaging comprised the largest portion of products
generated, at 33 percent (69 million tons) of total MSW generation. Nondurable
goods were the second largest fraction, comprising about 27 percent (56 million
tons). The third main category of products is durable goods, which comprised 15
percent (32 million tons) of total MSW generation.
Figure ES-2. Products generated in MSW by weight, 1996
(Total weight = 209.7 million tons)
Nondurable goods 26.5%
55.7 million tons
Durable goods 15.1%
31.7 million tons
Containers & packaging 33.0%
69.2 million tons
Food, other 12.0'
25.1 million tons
Yard trimmings 13.4%
28.0 million tons
-------
Table ES-2 shows the generation and recovery of the product categories in
MSW. Recovery of containers and packaging was the highest of the three
product categories—40 percent of containers and packaging generated in 1996
were recovered for recycling. About 52 percent of aluminum packaging was
recovered (mostly aluminum beverage cans), while more than 56 percent of steel
packaging (mostly cans) was recovered. Paper and paperboard packaging recovery
was estimated at 54 percent; corrugated containers accounted for most of that
figure. Approximately 29 percent of glass containers were recovered overall,
while about 8 percent of wood packaging (mostly pallets removed from service)
was recovered for recycling. About 10 percent of plastic containers and packaging
was recovered in 1996, mostly soft drink, milk, and water bottles.
Overall recovery of nondurable goods was 23 percent in 1996. Newspapers
constituted the largest portion of this recovery, with 54 percent of newspapers
generated being recovered for recycling. High-grade office papers and magazines
were also recovered in significant quantities in 1996, at 48 percent and 24 percent,
respectively. About 16 percent of clothing and other textile nondurable products
also were recovered for recycling.
Overall, durable goods were recovered at a rate of 17 percent in 1996, up
from 16 percent in 1995. Nonferrous metals had one of the highest recovery
rates, at 67 percent, due to the high rate of lead recovery from lead-acid batteries.
Nearly 32 percent of ferrous metals were recovered from appliances and
miscellaneous durable goods. Excluding retreads and tire-derived fuel use, over
18 percent of tires also were recovered for recycling.
Residential and Commercial Sources of MSW
Sources of MSW, as characterized in this report, include both residential
and commercial locations. Residential waste (including waste from multi-family
dwellings) is estimated to be 55 to 65 percent of total MSW generation.
Commercial waste (including waste from schools, some industrial sites where
packaging is generated, and businesses) constitutes between 35 and 45 percent.
Local and regional factors, such as climate and level of commercial activity,
contribute to these variations.
-------
Table ES-2
GENERATION AND RECOVERY OF PRODUCTS IN MSW
BY MATERIAL, 1996
(In millions of tons and percent of generation of each product)
Durable goods
Ferrous metals
Aluminum
Other non-ferrous metals
Total metals
Glass
Plastics
Rubber and leadier
Wood
Textiles
Other materials
Total durable goods
Nondurable goods
Paper and paperboard
Plastics
Rubber and leather
Textiles
Other materials
Total nondurable goods
Containers and packaging
Steel
Aluminum
Total metals
Glass
Paper and paperboard
Plastics
Wood
Other materials
Total containers and packaging
Other wastes
Food wastes
Yard trimmings
Miscellaneous inorganic wastes
Total other wastes
TOTAL MUNICIPAL SOLID WASTE
Weight
Generated
Weight
Recovered
Recovery
as a Percent
of Generation
8.8
0.8
1.3
10.9
1.3
6.3
5.4
4.3
2.4
1.0
31.7
2.8
Neg.
0.8
3.7
Neg.
0.3
0.6
Neg.
0.1
0.8
5.4
31.8%
Neg.
66.8%
33.4%
Neg.
4.0%
11.0%
Neg.
5.3%
74.7%
17.1%
41.4
5.3
0.8
5.2
2.8
55.7
12.0
Neg.
Neg.
0.8
Neg.
12.9
29.0%
<1%
Neg.
15.8%
Neg.
23.1%
3.0
2.0
4.9
11.0
38.5
8.2
6.5
0.1
69.2
1.7
1.0
2.7
3.2
20.6
0.8
0.5
Neg.
27.7
56.4%
52.2%
54.7%
28.7%
53.5%
9.8%
7.5%
Neg.
40.1%
21.9
28.0
3.2
53.1
209.7
0.5
10.8
Neg.
11.3
57.3
2.4%
38.6%
Neg.
21.3%
27.3%
Includes wastes from residential, commercial, and institutional sources.
Neg. - less than 50,000 tons or 0.05 percent.
-------
MANAGEMENT OF MSW
EPA's integrated waste management hierarchy includes the following
components:
• Source reduction (including reuse of products and backyard
composting of yard trimmings).
• Recycling (including composting).
• Waste combustion (preferably with energy recovery) and
landfilling.
Figure ES-3 shows how much MSW was recovered for recycling
(including composting) and how much was disposed of by combustion and
landfilling in 1996. Approximately 27 percent (57 million tons) of MSW was
recycled and composted; an estimated 17 percent (36 million tons) was combusted
(nearly all with energy recovery); and the remainder, 55 percent (116 million
tons), was landfilled. (Although, of this total small amounts may have been
littered or self-disposed rather than landfilled.)
Figure ES-3. Management of MSW in U.S., 1996
(Total weight = 209.7 million tons)
Landfill, other, 55.5%
116.3 million tons
Recovery for recycling
(including composting), 27.3%
57.3 million tons
Combustion, 17.2%
36.1 million tons
-------
Source Reduction
Source reduction includes the design, manufacture, purchase, or use of
materials, such as products and packaging, to reduce their amount or toxicity
before they enter the MSW management system. Some examples of source
reduction activities are:
• Designing products or packaging to reduce the quantity or the
toxicity of the materials used, or to make them easy to reuse.
• Reusing existing products or packaging.
• Lengthening the lives of products to postpone disposal.
• Using packaging that reduces the amount of damage or spoilage to
the product.
• Managing nonproduct organic wastes (e.g., food scraps and yard
trimmings) through on-site composting or other alternatives to
disposal (e.g., leaving grass clippings on the lawn).
Product source reduction activities are not quantified at the national level
in this report. The report does include a section discussing source reduction
trends in packaging and nondurable paper products.
On a per-person basis, generation of packaging has been about constant,
while at the same time, consumption of food and other products has been
increasing. Again on a per-person basis, generation of nondurable paper products
(newspapers, office papers, mail, and other printed products) has been about
constant since 1990, compared to rapid increases in previous years. At the same
time, electronic communication media (e-mail, Internet) have been increasing
rapidly. There also has been some shift of advertising dollars from printed media
to nonprinted media (television, radio, Internet). Trends are not yet clear, but
electronic communications and data exchange may be slowing the rate of growth
of paper products.
-------
Recovery
Recovery for recycling (including composting) continues to be one of the
most effective waste management techniques. In it's Annual Survey of solid
waste management practices, BioCycle Magazine (April 1997) reports that
approximately 51 percent of the U.S. population (135 million people) had access
to the nation's nearly 9,000 curbside recycling programs in 1996. Seventy-five
percent of the programs were in the Northeast and Midwest. In addition, over
10,000 drop-off centers for recyclables were reported in 1996. About 360 materials
recovery facilities helped process the recyclables collected in 1996. An estimated
3,300 yard trimmings composting programs (not backyard composting) existed in
1996; the majority of these programs were in the Northeast and Midwest.
Combustion
Most MSW combustion in the United States involves the recovery of an
energy product (generally steam or electricity). Total MSW combustion with
energy recovery, referred to as waste-to-energy combustion, currently has a
design capacity of 100,000 tons per day. There were 110 waste-to-energy
combustion facilities in the United States in 1996; nearly 40 percent of these were
located in the Northeast, accounting for 48 percent of total design capacity. In
addition, there were 8 facilities preparing refuse-derived fuel, and a small
amount of capacity (2,000 tons per day) for incineration without energy recovery.
Landfilling
Although the number of landfills in the United States is decreasing,
landfill capacity has remained relatively constant. In 1996, approximately 2,400
municipal solid waste landfills were reported in the contiguous United States,
with the Southeast and West having the greatest number of landfills. Thirty-five
states had landfills reporting more than 10 years of capacity remaining. Only
three states reported having less than 5 years of capacity left.
-------
Trends in MSW Management
MSW generation grew from 88 million tons in 1960 to 214 million tons in
1994 but has since dropped off to about 210 million tons in 1996 (Figure ES-4). In
the 1960s and early 1970s, a large percentage of MSW was burned. Through the
mid-1980s, incineration declined considerably and landfills became more difficult
to site. MSW generation continued to rise, however, while materials recovery
rates increased slowly. As a result, the burden on the nation's landfills grew
dramatically. Although there are now fewer municipal solid waste landfills,
their average size has increased and capacity at the national level does not appear
to be a problem. However, regional dislocations sometimes occur. As recovery
rates increased in the late 1980s and early 1990s—and combustion stayed
constant—discards to landfills have steadily decreased.
Figure ES-4. Municipal Solid Waste Management, 1960 to 1996
Recoveiy for Recycling
Combustion
Recoveiy for the Composting
Component of Recycling
1960 1965 1970 1975 1980 1985 1990 1995
------- |