Municipal Solid Waste (MSW) - Some basic Facts
MSW—more commonly known as trash or garbage—consists
of everyday items such as product packaging, grass clippings,
furniture, clothing, bottles, food scraps, newspapers, appliances,
paint, and batteries. To learn more about MSW, view our interactive
presentation about Milestones
in Garbage: 1990–Present.
In 2003, U.S. residents, businesses, and institutions
produced more than 236 million tons
of
MSW, which is approximately 4.5 pounds of waste per person
per day.
Several MSW management practices, such as source reduction,
recycling, and composting, prevent or divert materials from
the wastestream. Source
reduction involves altering the design, manufacture, or
use of products and materials to reduce the amount and toxicity
of what gets thrown away. Recycling diverts
items, such as paper, glass, plastic, and metals, from the
wastestream. These materials are sorted, collected, and processed
and then manufactured, sold, and bought as new products. Composting decomposes
organic waste, such as food scraps and yard trimmings, with
microorganisms (mainly bacteria and fungi), producing a humus-like
substance.
Other practices address those materials
that require disposal. Landfills are
engineered areas where waste is placed into the land. Landfills
usually have liner systems and other safeguards to prevent
groundwater contamination. Combustion is
another MSW practice that has helped reduce the amount of landfill
space needed. Combustion facilities burn MSW at a high temperature,
reducing waste volume and generating electricity.
Solid Waste Hierarchy
EPA has ranked the most environmentally sound strategies for
MSW. Source reduction (including reuse) is the most preferred
method, followed by recycling and composting, and, lastly,
disposal in combustion facilities and landfills.
Currently, in the United States, 30 percent is recovered and
recycled or composted, 14 percent is burned at combustion facilities,
and the remaining 56 percent is disposed of in landfills.
Source Reduction (Waste Prevention)
Source reduction can be a successful method of reducing waste
generation. Practices such as grasscycling, backyard composting,
two-sided copying of paper, and transport packaging reduction
by industry have yielded substantial benefits through source
reduction.
Source reduction has many environmental benefits. It prevents
emissions of many greenhouse gases, reduces pollutants, saves
energy, conserves resources, and reduces the need for new landfills
and combustors.
Recycling
Recycling,
including composting, diverted
72 million tons of material away from disposal in 2003, up
from 15 million tons in 1980, when the recycle rate was just
10% and 90% of MSW was being recycled.
Typical materials that are recycled include batteries, recycled
at a rate of 93%, paper and paperboard at 48%, and yard trimmings
at 56%. These materials and others may be recycled through
curbside programs, drop-off centers, buy-back programs, and
deposit systems.
Recycling prevents the emission of many greenhouse gases and
water pollutants, saves energy, supplies valuable raw materials
to industry, creates jobs, stimulates the development of greener
technologies, conserves resources for our children’s
future, and reduces the need for new landfills and combustors.
Recycling also helps reduce greenhouse gas emissions that
affect global climate. In 1996, recycling of solid waste in
the United States prevented the release of 33 million tons
of carbon into the air—roughly the amount emitted annually
by 25 million cars.
Combustion/Incineration
Burning MSW can generate energy while reducing the amount
of waste by up to 90 percent in volume and 75 percent in weight.
EPA’s Office
of Air and Radiation is primarily responsible for regulating
combustors because air emissions from combustion pose the
greatest environmental concern.
In 2001, in the United States, there were 97 combustors with
energy recovery with the capacity to burn up to 95,000 tons
of MSW per day.
Landfills
Under the Resource Conservation and Recovery Act (RCRA), landfills
that accept MSW are primarily regulated by state, tribal, and
local governments. EPA, however, has established national standards
these landfills must meet in order to stay open. Municipal
landfills can, however, accept household
hazardous waste.
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Resource Conservation and Recovery Act |
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The Resource Conservation and
Recovery Act (RCRA) was enacted by Congress in 1976
and amended in 1984. The act's primary goal is to
protect human health and the environment from the
potential hazards of waste disposal. In addition,
RCRA calls for conservation of energy and natural
resources, reduction in waste generated, and environmentally
sound waste management practices. |
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The number of landfills in the United States is steadily decreasing—from
8,000 in 1988 to 1,767 in 2002. The capacity, however, has
remained relatively constant. New landfills are much larger
than in the past.
Household Hazardous Waste
Households often discard many common items such as paint,
cleaners, oils, batteries, and pesticides, that contain hazardous
components. Leftover portions of these products are called household
hazardous waste (HHW). These products, if mishandled, can
be dangerous to your health and the environment.
Environmental Terms, Abbreviations, and Acronyms
EPA provides a glossary that
defines in non-technical language commonly used environmental
terms appearing in EPA publications and materials. It also
explains abbreviations and acronyms used throughout EPA.
Recommended Sources for MSW Information
- Municipal
Solid Waste in the United States: 2003 Facts and Figures: Describes
the national MSW stream based on data collected between
1960 and 2003. Includes information on MSW generation,
recovery, and discard quantities; per capita generation
and discard rates; and residential and commercial portions
of MSW generation.
- Decision-Maker’s
Guide to Solid Waste Management, Volume II: Contains
technical and economic information to assist solid waste
management practitioners in planning, managing, and operating
MSW programs and facilities. Includes suggestions for
best practices when planning or evaluating waste and
recycling collection systems, source reduction and composting
programs, public education, and landfill and combustion
issues.
Additional MSW materials can be found
at Publications.