please see attachment’s to help with this assignment.
21.1a
Solid
Wast
e
Is Piling
Up
Think about what you have
to
ssed in the
trash
today. Perhaps it was
leftovers from lunch
,
an
empty can
or
plastic bottle, or something you no
longer needed. People throw away all sorts of items, and they all add up to
huge amounts of
solid
waste
.
In the natural world, there
is
essentially no waste because the wastes
of one
organism become nutrients or raw materials for others in food
chains and food webs. This natural cycling of nutrients is the basis of the
chemical cycling
principles of sustainability
We violate this principle by producing huge amounts of waste materials
that are burned or buried in landfills or that end up as litter. For example,
the manufacturing of a desktop computer requires 700 or more different
materials obtained from mines, oil wells, and chemical factories all over the
world. For every 0.5 kilogram
(1 pound) of electronics it contains,
approximately 3,600 kilograms (8,000 pounds) of waste were created
—
an
amount roughly equal to the weight of a large pickup truck.
Because of the law of conservation of matter (
Chapter 2
,
Law of
Conservation of Matter
) and the nature of human lifestyles, we will always
produce some waste. However, studies and experience indicate that by
mimicking nature, through strategies such as cradle
–
to-
cradle design (
Core
Case Study
), we could reduce this waste of potential resources and the
resulting environmental harm by up to 80%.
One major category of waste is
solid waste
—
any unwanted or discarded
material people produce that is not a liquid or a gas. There are two major
types of solid waste. The first is
industrial solid waste
produced by mines,
farms, and industries that supply us with goods
and services. The second
is
municipal solid waste (MSW)
, often called
garbage
or trash
. It consists
of the combined solid wastes produced by homes and workplaces other
than factories. Examples of MSW include paper, cardboard,
food wastes,
cans, bottles, yard wastes, furniture, plastics, glass, wood, and electronics
or e-waste
(see chapter
–
opening photo).
Much of the world’s MSW ends up as litter in rivers, lakes, the ocean, and
natural landscapes (
Figure 21.2
). One of the major symbols of such waste is
the single
–
use plastic bag. Laid end
-to-
end, the 100 billion plastic bags used
in the United States each year would reach to the moon and back 60 times.
In many countries, the landscape, lakes, and r
ivers are littered with plastic
bags, as are the oceans. Plastic bags can take 400 to 1,000 years to degrade.
Figure 21.2
Municipal solid waste: Various types of solid waste have been dumped in this isolated mountain area of the United States.
Mikadun/
Shutterstock.com
In the environment, plastic bags often block drains and sewage systems and can kill wildlife and livestock that try to eat them or become ensnared in them. In Kenya, Africa, outbreaks of malaria have been associated with plastic bags lying on the ground collecting water in which malaria-carrying mosquitoes can breed.
Discarded plastic items are a threat to many terrestrial animal species, as well as millions of seabirds, marine mammals, and sea turtles, which can mistake a floating plastic sandwich bag for a jellyfish or get caught in plastic fishing nets (
Figure 11.9
). In 2019, a dead whale found on beach in the Philippines had 40 kilograms (88 pounds) of plastic in its stomach. About 80% of the plastics in the ocean are blown or washed in from beaches, rivers, storm drains, and other sources, and the rest are dumped into the ocean from ocean-going garbage barges, ships, and fishing boats.
In more-developed countries, most MSW is collected and buried in landfills or burned in incinerators. In many less-developed countries, much of it ends up in open dumps, where poor people eke out a living finding items they can use or sell (
Figure 21.3
). In China, only about 40% of the MSW is collected, and in rural areas the figure can be as low as 4–5%. The United States is the world’s largest producer of solid waste (see
Case Study
that follows).
Figure 21.3
This child is searching for useful items in this open trash dump in Manila, The Philippines.
Stockbyte/Thinkstock
Case Study
Solid Waste in the United States
According to the U.S. Environmental Protection Agency (EPA), 98.5% of all solid waste produced in the United States is industrial waste from mining (76%), agriculture (13%), and industry (9.5%). The remaining 1.5% is MSW. The United States with 4% of the world’s population generates about 40% of the world’s solid waste, more than any other country. The U.S. also leads the world in solid waste per person, amounting to 2.0 kilograms (4.4 pounds) a day or 730 kilograms (1,606 pounds) a year. About $1 of every $10 Americans spend to buy things goes for packaging that is thrown away, explaining why paper and plastic packaging makes up about 40% of U.S. household trash. Every year, Americans generate enough MSW to fill a bumper-to-bumper convoy of garbage trucks long enough to circle the earth’s equator almost six times. Most of this waste is dumped in landfills, recycled or composted, or incinerated (
Figure 21.4
, right). However, much of it ends up as litter.
Figure 21.4
Composition of MSW in the United States and data on where it goes after collection.
Data Analysis:
1. How many times more than the amount recycled is the amount of materials put into landfills?
(Compiled by the authors using data from U.S. Environmental Protection Agency)
Consider some of the solid wastes that consumers throw away each year, on average, in the high-waste economy of the United States:
· Enough tires to encircle the earth’s equator almost three times.
· An amount of disposable diapers that, if linked end to end, would reach to the moon and back seven times.
· Enough carpet to cover the state of Delaware.
· Enough nonreturnable plastic bottles to form a stack that would reach from the earth to the moon and back about six times.
·
About 100 billion throwaway plastic shopping bags, or 274 million per day, an average of nearly 3,200 every second.
· Enough office paper to build a wall 3.5 meters (11 feet) high across the country from New York City to San Francisco, California.
Most of these wastes break down very slowly, if at all. Lead, mercury, glass, Styrofoam, and most plastic bottles do not break down completely. An aluminum can takes 500 years to disintegrate. Disposable diapers may take 550 years to break down, and a plastic shopping bag may stick around for up to 1,000 years.
Some resource experts suggest we change the name of the trash we produce from MSW to MWR—mostly wasted resources. So much of what is considered “waste” can be useful as a resource (
Science Focus 21.1
).
Science Focus 21.1
Garbology and Tracking Trash
How do we know about the composition of trash in landfills? Much of that information comes from research by garbologists such as William Rathje, an anthropologist who pioneered the field of garbology in the 1970s at the University of Arizona. These scientists work like archaeologists, training their students to sort, weigh, and itemize people’s trash, and to bore holes to remove cores of materials from garbage dumps and analyze what they find.
Many people think of landfills as huge compost piles where biodegradable wastes are decomposed within a few months. In fact, decomposition inside modern landfills is a slow process. Trash buried inside sanitary landfills can resist decomposition perhaps for centuries because it is tightly packed and protected from sunlight, water, and air, and from the bacteria that could digest and decompose most of these wastes. In fact, researchers have unearthed 50-year-old newspapers that were still readable and hot dogs and pork chops that had not yet decayed.
A team of researchers, led by Carlo Riatti, at the Massachusetts Institute of Technology (MIT) conducted a project called “Trash Track.” The project’s goals were to find out where urban trash goes and help New York City increase its recycling rate from the current 30% to 100% by 2030.
The researchers attached wireless transmitters about the size of a matchbook to several thousand different items of trash produced by volunteer participants in New York City, Seattle, Washington, and London, England. Every few hours, these devices use GPS technology to send their locations via a cell phone network to a computer at MIT, which plots their movements. This system tracks the trash items on their trips to recycling plants, landfills, or incinerators, and this helps researchers determine how and where trash goes.
Critical Thinking
1. How might such a system help us to learn about the environmental costs of waste management such as the amount of pollution generated in the hauling and processing of waste? Explain.
21.1bHazardous Waste
Another major category of waste is
hazardous
, or
toxic waste
. It is any discarded material that threatens human health or the environment because it is toxic, corrosive, or flammable, can undergo violent or explosive chemical reactions, or can cause disease. Examples include industrial solvents, hospital medical waste, car batteries (containing acids and toxic lead), household pesticide products, dry-cell batteries (containing mercury and cadmium), and ash and sludge from incinerators and coal-burning power and industrial plants. Improper handling of these wastes can lead to pollution of air and water, degradation of ecosystems, and health threats. The fastest-growing category of waste, which contains a large amount of hazardous waste, is electronic, or e-waste (see the Case Study that follows).
Case Study
E-Waste—A Serious Hazardous Waste Problem
What happens to your cell phone, computer, television set, and other electronic devices when they are no longer useful? They become electronic waste, or e-waste—the fastest-growing solid waste problem in the United States and China (see chapter-opening photo). Each year, the world generates approximately 300,000 metric tons (330,000 tons) of worn out lithium-ion batteries from electronic devices. This will increase as sales of plug-in hybrid (see
Figure 16.4
) and all-electric vehicles increase and need battery replacements. This battery e-waste is a source of valuable metals such as cobalt, nickel, and lithium that can be sold to battery companies.
Between 2000 and 2018, the recycling of U.S. e-waste increased from 10% to 26%, according to the EPA. Much of the remaining e-waste went to landfills and incinerators. Much e-waste contains gold, rare earths, and other valuable materials that could be recycled or reused. In 2016, an estimated $22 billion in gold was thrown away in e-waste. E-waste also is a source of toxic and hazardous chemicals that can contaminate air, surface water, groundwater, and soil and cause human health problems.
Until 2017, much of the e-waste in the United States was shipped to China, India, and other Asian and African countries for processing. Labor is cheap and environmental regulations are weak in those countries. Workers there—many of them children—dismantle, burn, and treat e-waste with acids to recover valuable metals and reusable parts. The work exposes them to toxic metals such as lead and mercury and other harmful chemicals. The remaining scrap is dumped into waterways and fields or burned in open fires that expose people to highly toxic chemicals called dioxins. However, China stopped accepting e-waste from the United States in 2017 because it was too contaminated.
Transfer of such hazardous waste from more-developed to less-developed countries is banned under the International Basel Convention. Despite this ban, much of the world’s e-waste is not officially classified as hazardous waste, or it is illegally smuggled out of some countries. The United States can export its e-waste legally because it has not ratified the Basel Convention.
The two main classes of hazardous wastes are organic compounds such as various solvents, pesticides, PCBs, dioxins, and toxic heavy metals such as lead, mercury, and arsenic.
Figure 21.5
lists some of the harmful chemicals found in many household products.
Figure 21.5
Harmful chemicals are found in many homes. The U.S. Congress has exempted the disposal of many of these household chemicals and other items from government regulation.
Question:
1. Which of these chemicals could you find in your home?
Top: tuulijumala/ Shutterstock.com. Center: Katrina Outland/ Shutterstock.com. Bottom: Agencyby/
Dreamstime.com
Another form of extremely hazardous waste is the highly radioactive waste produced by nuclear power plants and nuclear weapons facilities (see
Chapter 1
5
). Such waste must be stored safely for at least 10,000 years. After 60 years of research, scientists and governments have not found a scientifically and politically acceptable way to safely isolate these dangerous wastes for such a long period of time.
According to the U.N. Environment Programme (UNEP), more-developed countries produce 80–90% of the world’s hazardous wastes. The United States is the top producer. China is closing in on the number one spot as it continues to industrialize rapidly without adequate pollution controls.
21.1bHazardous Waste
Another major category of waste is
hazardous
, or
toxic waste
. It is any discarded material that threatens human health or the environment because it is toxic, corrosive, or flammable, can undergo violent or explosive chemical reactions, or can cause disease. Examples include industrial solvents, hospital medical waste, car batteries (containing acids and toxic lead), household pesticide products, dry-cell batteries (containing mercury and cadmium), and ash and sludge from incinerators and coal-burning power and industrial plants. Improper handling of these wastes can lead to pollution of air and water, degradation of ecosystems, and health threats. The fastest-growing category of waste, which contains a large amount of hazardous waste, is electronic, or e-waste (see the Case Study that follows).
Case Study
E-Waste—A Serious Hazardous Waste Problem
What happens to your cell phone, computer, television set, and other electronic devices when they are no longer useful? They become electronic waste, or e-waste—the fastest-growing solid waste problem in the United States and China (see chapter-opening photo). Each year, the world generates approximately 300,000 metric tons (330,000 tons) of worn out lithium-ion batteries from electronic devices. This will increase as sales of plug-in hybrid (see Figure 16.4) and all-electric vehicles increase and need battery replacements. This battery e-waste is a source of valuable metals such as cobalt, nickel, and lithium that can be sold to battery companies.
Between 2000 and 2018, the recycling of U.S. e-waste increased from 10% to 26%, according to the EPA. Much of the remaining e-waste went to landfills and incinerators. Much e-waste contains gold, rare earths, and other valuable materials that could be recycled or reused. In 2016, an estimated $22 billion in gold was thrown away in e-waste. E-waste also is a source of toxic and hazardous chemicals that can contaminate air, surface water, groundwater, and soil and cause human health problems.
Until 2017, much of the e-waste in the United States was shipped to China, India, and other Asian and African countries for processing. Labor is cheap and environmental regulations are weak in those countries. Workers there—many of them children—dismantle, burn, and treat e-waste with acids to recover valuable metals and reusable parts. The work exposes them to toxic metals such as lead and mercury and other harmful chemicals. The remaining scrap is dumped into waterways and fields or burned in open fires that expose people to highly toxic chemicals called dioxins. However, China stopped accepting e-waste from the United States in 2017 because it was too contaminated.
Transfer of such hazardous waste from more-developed to less-developed countries is banned under the International Basel Convention. Despite this ban, much of the world’s e-waste is not officially classified as hazardous waste, or it is illegally smuggled out of some countries. The United States can export its e-waste legally because it has not ratified the Basel Convention.
The two main classes of hazardous wastes are organic compounds such as various solvents, pesticides, PCBs, dioxins, and toxic heavy metals such as lead, mercury, and arsenic. Figure 21.5 lists some of the harmful chemicals found in many household products.
Figure 21.5
Harmful chemicals are found in many homes. The U.S. Congress has exempted the disposal of many of these household chemicals and other items from government regulation.
Question:
1. Which of these chemicals could you find in your home?
Top: tuulijumala/ Shutterstock.com. Center: Katrina Outland/ Shutterstock.com. Bottom: Agencyby/ Dreamstime.com
Another form of extremely hazardous waste is the highly radioactive waste produced by nuclear power plants and nuclear weapons facilities (see Chapter 15). Such waste must be stored safely for at least 10,000 years. After 60 years of research, scientists and governments have not found a scientifically and politically acceptable way to safely isolate these dangerous wastes for such a long period of time.
According to the U.N. Environment Programme (UNEP), more-developed countries produce 80–90% of the world’s hazardous wastes. The United States is the top producer. China is closing in on the number one spot as it continues to industrialize rapidly without adequate pollution controls.
21.2aWaste Management
Society can deal with the solid wastes it creates in two ways. One is
waste management
, which focuses controlling wastes and reducing their environmental harm. This approach begins with the question, “What do we do with solid waste?” It typically involves mixing wastes together and then burying them, burning them, or shipping them to another location.
The other approach is
waste reduction
, which focuses on producing much less solid waste and reusing, recycling, or composting much of what is produced. This approach begins with questions such as “How can we avoid producing so much solid waste?” and “How can we use the waste we produce as resources like nature does?
Most analysts call for using
integrated waste management
—a variety of coordinated strategies for both waste management and waste reduction (
Figure 21.6
).
Figure 21.7
compares the science-based waste management goals of the EPA and National Academy of Sciences with waste management trends based on actual data.
Figure 21.6
Integrated waste management: We can reduce wastes by refusing or reducing resource use and by reusing, recycling, and composting what we discard, or we can manage them by burying them in landfills or incinerating them. Most countries rely primarily on burial and incineration.
Critical Thinking:
1. What happens to the solid waste you produce?
Left to right: Mariyana M/ Shutterstock.com, Sopotnicki/ Shutterstock.com, Scanrail1/ Shutterstock.com, chris kolaczan/ Shutterstock.com, vilax/ Shutterstock.com, MrGarry/ Shutterstock.com, Le Do/ Shutterstock.com
Figure 21.7
Priorities recommended by the U.S. National Academy of Sciences for dealing with municipal solid waste (left) compared with actual waste-handling practices in the United States based on data (right).
Critical Thinking:
1. Why do you think most countries do not follow most of the scientific-based priorities listed on the left?
(Compiled by the authors using data from U.S. Environmental Protection Agency, U.S. National Academy of Sciences, Columbia University, and BioCycle.)
Let us look more closely at the options in the order of priorities suggested by scientists (
Figure 21.7, left)
21.2bThe Four Rs of Waste Reduction
A more sustainable approach to dealing with solid waste is to first reduce it, then reuse or recycle it, and finally safely dispose of what is left. This waste reduction approach (Figure 21.7, left) is called the Four Rs, listed below in order of priority suggested by scientists:
·
Refuse
: Don’t use it.
·
Reduce
: Use less of it.
·
Reuse
: Use it over and over.
·
Recycle
: Convert used resources to useful items and buy products made from recycled materials. An important form of recycling is
composting
, which mimics nature by using bacteria and other decomposers to break down yard trimmings, vegetable food scraps, and other biodegradable organic wastes into materials than can be used to improve soil fertility.
The first three Rs are preferred because they are waste prevention approaches that tackle the problem of waste production before it occurs. Recycling is important, but it deals with waste after it has been produced. By refusing, reducing, reusing, and recycling people consume less matter and energy resources, reduce pollution and natural capital degradation, and save money. Some scientists and economists estimate that we could eliminate up to 80% of the solid waste we produce if we followed the four Rs strategy. This would mimic the earth’s chemical cycling principle of sustainability.
Figure 21.8
lists ways in which you can use the four Rs of waste reduction to reduce your output of solid waste.
Figure 21.8
Individuals matter: You can save resources by reducing your output of solid waste and pollution.
Critical Thinking:
1. Which three of these steps do you think are the most important ones to take? Why? Which of these things do you already do?
Here are six strategies that some industries and communities use to reduce resource use, waste, and pollution and to promote the cradle-to-cradle approach to design, manufacturing, and marketing (
Core Case Study
).
First, change industrial processes to eliminate or reduce the use of harmful chemicals. Since 1975, the 3M Company has taken this approach and, in the process, saved $1.9 billion (see
Chapter 17
, Case Study).
Second, redesign manufacturing processes and products to use less material and energy. For example, the weight of a typical car has been reduced by about one-fourth since the 1960s with the use of lighter steel, aluminum, magnesium, plastics, and composite materials.
Third, develop products that are easy to repair, reuse, remanufacture, compost, or recycle. For example, some Xerox photocopiers that are leased by businesses are made of reusable or recyclable parts that allow for easy remanufacturing. They are projected to save the company $1 billion in manufacturing costs.
Fourth, establish cradle-to-cradle responsibility laws that require companies to take back various consumer products such as electronic equipment, appliances, and motor vehicles for recycling or remanufacturing, as Japan and many European countries do.
Fifth, eliminate or reduce unnecessary packaging. Use the following hierarchy for product packaging: no packaging, reusable packaging, and recyclable packaging.
Sixth, use fee-per-bag solid waste collection systems that charge consumers for the amount of waste they throw away but provide free pickup of recyclable and reusable items.
21.3aAlternatives to the Throwaway Economy
People in today’s industrialized societies have increasingly substituted throwaway items for reusable ones, which has resulted in growing masses of solid waste. By applying the four Rs, society can slow or stop this trend. Individuals can guide and reduce their consumption of resources by asking questions such as these:
· Do I really need this? (refusing)
· How many of these do I actually need? (reducing)
· Is this something I can use more than once? (reusing)
· Can the material in this be used to make another product or material when I am done with it? (recycling)
21.3bReuse
Cradle-to-cradle design (
Core Case Study) elevates reuse to a new level. According to William McDonough (
Individuals Matter 21.1
), the key to shifting to a reuse economy is to design for it. For example, some manufacturers of computers, furniture, photocopiers, and other products have designed their products so that when they are no longer useful, they can be retrieved from consumers for repair or remanufacture.
Individuals Matter 21.1
William McDonough
US/SIPA/Sipa Press/Beijing China/Newscom
William McDonough is an architect, designer, and visionary thinker, devoted to the earth-friendly design of buildings, products, and cities.
McDonough view wastes as resources out of place because of poor design. He also notes that humans have been releasing a growing number of chemicals into the environment faster than the natural chemical cycles can remove them. In addition, many of these synthetic chemicals cannot be broken down and recycled by natural processes. Many of these chemicals end up polluting the air, water, and soil and threatening the health of humans and other life forms.
McDonough would use environmentally and economically sustainable design to mimic nature by reusing and recycling the chemicals and products we make with the goal of zero waste. His cradle-to-cradle design approach (Core Case Study) has been applied in numerous projects, including the Adam Joseph Lewis Center for Environmental Studies at Oberlin College. Architects and designers view it as one of the most important and inspiring examples of environmentally friendly design. It uses recycled and nontoxic materials that can be further recycled. It gets heat from the sun and the earth’s interior and electricity from solar cells, and it produces 13% more energy than it consumes. The building’s greenhouse contains an ecosystem of plants and animals that purify the building’s sewage and wastewater. Rainwater is collected and used to irrigate the surrounding green space, which includes a restored wetland, a fruit orchard, and a vegetable garden.
McDonough has been recognized by Time magazine as a “Hero for the Planet.” He has also received numerous design awards and three presidential awards. He believes we can use cradle-to-cradle design to leave the world better off than we found it.
One way to implement cradle-to-cradle design is for governments to ban or severely restrict the disposal of certain items. For example, the European Union (EU) has led the way by banning e-waste from landfills and incinerators. Some European nations, Japan, and China are using a take-back approach, in which electronics manufacturers are required to take back their products at the end of their useful lives. To cover the costs of these programs, consumers pay a recycling tax on electronic products, an example of helping implement the full-cost pricing principle of sustainability. The United States has no federal take-back law, but according to the Electronics TakeBack Coalition, more than 20 states have such laws and several more are considering them.
Governments have also banned the use of certain throwaway items. For example, Finland bans all beverage containers that cannot be reused, and consequently, 95% of that country’s soft drink, beer, wine, and spirits containers are refillable. The use of rechargeable batteries is cutting toxic waste by reducing the amount of conventional batteries that are thrown away. The newest rechargeable batteries come fully charged, can hold a charge for up to two years when they are not used, and can be recharged in about 15 minutes.
In many countries, the landscape is littered with plastic bags. They can take 400 to 1,000 years to break down and can kill animals that try to eat them or become ensnared in them. Huge quantities of plastic bags and other plastic products end up in the ocean (
Figure 20.16
). Many people are using reusable cloth or plastic bags instead of throwaway paper or plastic bags to carry groceries and other items they buy. However, the bags must be reused about 20 times to offset the harmful environmental effects of producing them before they help reduce your harmful environmental impact.
By 2018, the governments of more than 40 countries, including China, Great Britain, France, Germany, the Netherlands, Rwanda, and Kenya were taxing plastic shopping bags or limiting or prohibiting their use. In Ireland, a tax of 25¢ per bag cut plastic bag litter by 90% as people switched to reusable bags. In England, plastic bag use dropped by 85% after the government imposed a charge on plastic bags. Kenyans who produce, sell, or use plastic bags face fines of up to $19,000 or four years in prison.
More than 350 U.S. cities, counties, and states have banned or taxed plastic bag use. This is despite intense lobbying against such bans by the plastics industry. Hawaii, California, and New York have banned single-use plastic bags for most retail sales.
Similarly, several cities are trying to encourage the use of reusable food containers. In 2015, New York City joined Seattle, Portland, San Francisco, and Washington, D.C., in banning the use of polystyrene foam food containers. New York also banned the sale of polystyrene foam packing peanuts and has called for designers and entrepreneurs to produce reusable or compostable replacements for these banned items.
An increasingly popular way to reuse things is through shared use. In Portland, Oregon, some homeowners have worked with their neighbors to create tool libraries instead of buying their own tools. Toy libraries are also evolving among young families whose toys are used only for a few months or years. Companies that rent out tools, garden equipment, and other household goods provide another outlet for shared use.
Figure 21.9
lists some other ways to reuse items.
Figure 21.9
Individuals matter: Some ways to reuse the items we purchase.
Questions:
1. Which of these suggestions have you tried and how did they work for you?
Brenda Carson/ Shutterstock.com
21.3cRecycling
The cradle-to-cradle approach (
Core Case Study
) gives the highest priority to reuse but also relies on recycling. Worn-out items from the technical cycle of cradle-to-cradle manufacturing are recycled or sent into the biological cycle where ideally they degrade and become biological nutrients (
Figure 21.1
).
McDonough breaks recycling down into two categories: upcycling and downcycling. Ideally, all discarded items would be upcycled—recycled into a form that is more useful than the recycled item was. In downcycling, the recycled product is still useful, but not as useful or long-lived as the original item.
Households and workplaces produce five major types of recyclable materials: paper products, glass, aluminum, steel, and some plastics. These materials can be reprocessed into new, useful products in two ways.
Primary recycling
involves using materials again for the same purpose. An example is recycling used aluminum cans into new aluminum cans.
Secondary recycling
involves downcycling or upcycling used items to make different products. For example, tires can be downcycled to make sandals.
Scientists and waste managers also distinguish between two types of recyclable wastes: preconsumer or internal waste generated in a manufacturing process, and postconsumer or external waste generated from use of products by consumers. Preconsumer waste makes up more than three-fourths of the total.
Recycling involves three steps: collecting materials for recycling, converting recycled materials to new products, and selling and buying of products that contain recycled material. Recycling is successful environmentally and economically only when all three of these steps are carried out.
Recent research based on actual data instead of models indicates that the United States recycles or composts about 24% of its MSW, which is significantly lower than the EPA estimate of 34%. Here are some recycling rates for several items in the United States: lead-acid batteries 99%, paper and paperboard 67%, steel 33%, and aluminum 19%. Experts say that with education and proper incentives, Americans could recycle and compost at least 80% of their MSW, in keeping with the chemical cycling principle of sustainability.
According to a United Nations University study, increasing piles of e-waste (see chapter-opening photo) are urban mines because of the valuable metals the waste contains. The world’s e-waste contains millions of tons of gold, iron, copper, silver, and aluminum. Yet, only 16% of the world’s e-waste and 29% of U.S. e-waste is recycled.
Some see recycling as a business opportunity. One company, the RecycleBank, has set up a system where consumers can earn points by recycling. The company attaches an electronic tag to a household’s recycling bins to measure how much the household is recycling. It then credits the household account with points that can be traded in—somewhat like frequent flyer miles—for rewards at businesses that have joined the program.
Composting is another form of recycling that mimics nature’s recycling of plant nutrients. It involves using bacteria to decompose yard trimmings, vegetable food scraps, and other biodegradable organic wastes into humus. When added to soil, humus helps supply plant nutrients, slow soil erosion, retain water, and improve crop yields.
People can compost food wastes, yard wastes, and other organic wastes in composting piles that must be turned over occasionally or in simple backyard containers (
Figure 21.10
). In the United States, more than 3,000 municipal composting programs recycle about 60% of the yard wastes in the country’s MSW (
Figure 21.11
). To be successful, a large-scale composting program must be located carefully and odors must be controlled, especially near residential areas. They must also exclude toxic materials that make the compost unsafe for fertilizing crops and lawns.
Figure 21.10
Backyard composting bin.
Jbphotographylt/ Dreamstime.com
Figure 21.11
Large-scale municipal composting site.
imging/ Shutterstock.com
To promote separation of wastes for recycling, about 7,000 communities in the United States use a pay-as-you-throw or fee-per-bag waste collection system. They charge households and businesses for garbage that is picked up, but do not charge them for picking up materials separated for recycling or reuse.
According to the Organization for Economic Cooperation and Development (OECD), Germany leads the world in recycling. It recycles 65% of its MSW, with consumers separating recyclable items into different categories and depositing them in color-coded bins found throughout the country. South Korea comes in second and recycles 59% of its MSW. Austria, Switzerland, Sweden, Belgium, and the Netherlands all recycle at least 50% of their MSW. Turkey, which recycles only 1% of its waste, is in last place.
21.3cRecycling
The cradle-to-cradle approach (
Core Case Study
) gives the highest priority to reuse but also relies on recycling. Worn-out items from the technical cycle of cradle-to-cradle manufacturing are recycled or sent into the biological cycle where ideally they degrade and become biological nutrients (
Figure 21.1
).
McDonough breaks recycling down into two categories: upcycling and downcycling. Ideally, all discarded items would be upcycled—recycled into a form that is more useful than the recycled item was. In downcycling, the recycled product is still useful, but not as useful or long-lived as the original item.
Households and workplaces produce five major types of recyclable materials: paper products, glass, aluminum, steel, and some plastics. These materials can be reprocessed into new, useful products in two ways.
Primary recycling
involves using materials again for the same purpose. An example is recycling used aluminum cans into new aluminum cans.
Secondary recycling
involves downcycling or upcycling used items to make different products. For example, tires can be downcycled to make sandals.
Scientists and waste managers also distinguish between two types of recyclable wastes: preconsumer or internal waste generated in a manufacturing process, and postconsumer or external waste generated from use of products by consumers. Preconsumer waste makes up more than three-fourths of the total.
Recycling involves three steps: collecting materials for recycling, converting recycled materials to new products, and selling and buying of products that contain recycled material. Recycling is successful environmentally and economically only when all three of these steps are carried out.
Recent research based on actual data instead of models indicates that the United States recycles or composts about 24% of its MSW, which is significantly lower than the EPA estimate of 34%. Here are some recycling rates for several items in the United States: lead-acid batteries 99%, paper and paperboard 67%, steel 33%, and aluminum 19%. Experts say that with education and proper incentives, Americans could recycle and compost at least 80% of their MSW, in keeping with the chemical cycling principle of sustainability.
According to a United Nations University study, increasing piles of e-waste (see chapter-opening photo) are urban mines because of the valuable metals the waste contains. The world’s e-waste contains millions of tons of gold, iron, copper, silver, and aluminum. Yet, only 16% of the world’s e-waste and 29% of U.S. e-waste is recycled.
Some see recycling as a business opportunity. One company, the RecycleBank, has set up a system where consumers can earn points by recycling. The company attaches an electronic tag to a household’s recycling bins to measure how much the household is recycling. It then credits the household account with points that can be traded in—somewhat like frequent flyer miles—for rewards at businesses that have joined the program.
Composting is another form of recycling that mimics nature’s recycling of plant nutrients. It involves using bacteria to decompose yard trimmings, vegetable food scraps, and other biodegradable organic wastes into humus. When added to soil, humus helps supply plant nutrients, slow soil erosion, retain water, and improve crop yields.
People can compost food wastes, yard wastes, and other organic wastes in composting piles that must be turned over occasionally or in simple backyard containers (
Figure 21.10
). In the United States, more than 3,000 municipal composting programs recycle about 60% of the yard wastes in the country’s MSW (
Figure 21.11
). To be successful, a large-scale composting program must be located carefully and odors must be controlled, especially near residential areas. They must also exclude toxic materials that make the compost unsafe for fertilizing crops and lawns.
Figure 21.10
Backyard composting bin.
Jbphotographylt/
Dreamstime.com
Figure 21.11
Large-scale municipal composting site.
imging/
Shutterstock.com
To promote separation of wastes for recycling, about 7,000 communities in the United States use a pay-as-you-throw or fee-per-bag waste collection system. They charge households and businesses for garbage that is picked up, but do not charge them for picking up materials separated for recycling or reuse.
According to the Organization for Economic Cooperation and Development (OECD), Germany leads the world in recycling. It recycles 65% of its MSW, with consumers separating recyclable items into different categories and depositing them in color-coded bins found throughout the country. South Korea comes in second and recycles 59% of its MSW. Austria, Switzerland, Sweden, Belgium, and the Netherlands all recycle at least 50% of their MSW. Turkey, which recycles only 1% of its waste, is in last place.
21.3dRecycling Paper
About 55% of the world’s industrial tree harvest is used to make paper. However, according to the U.S. Department of Agriculture, we could make tree-free paper from straw and other agricultural residues and from the fibers of rapidly growing plants such as kenaf (see
Figure 10.15
) and hemp.
100 Million
Number of trees used each year to produce the world’s junk mail
Paper is the dominant material in the MSW of Canada and the United States. Each year, approximately 1 billion trees worth of paper are thrown away in the United States. Each American throws away an average of 309 kilograms (680 pounds) of paper a year.
The United States recycles about 67% of its paper and paperboard, according to the EPA. Paper (especially newspaper and cardboard) is easy to recycle. Recycling newspaper involves removing its ink, glue, and coating and then reconverting the paper to pulp, which is used to make new paper. Making recycled paper produces 35% less water pollution and 74% less air pollution than does making paper from wood pulp, and, no trees are cut down. Recycling a ton of paper saves 17 mature trees, 26,400 liters (7,000 gallons) of water, and 300 liters (2 barrels) of oil. Recycling all of the country’s newspapers would save about 250 million trees a year.
Connections
Recycling Paper and Reducing Emissions
According to the U.S. Energy Information Administration, recycled paper requires 10–30% less energy, which means that for every kilogram (2.2 pounds) of paper you recycle, you can prevent an average of 0.9 kilograms (2 pounds) of emissions.
21.3eRecycling
Glass
The glass recycling rate in the United States is roughly 33%, compared to 90% in Germany and Switzerland. In recent years, it has become more costly for some communities to recycle glass than to dump it in landfills. Particularly in places where recyclables are mixed by consumers and sorted at privately or publicly owned materials recovery facilities, the cost of separating broken glass from garbage has gone up because the amount of nonrecyclable trash in recycling bins is increasing.
In order to gain these environmental benefits, some communities are subsidizing the recycling of glass. Another approach to this problem would be to reuse glass jars and bottles to store food and other household items.
21.3fRecycling
Plastics
Plastics consist of various types of large polymers, or resins—organic molecules made by chemically linking organic chemicals produced mostly from oil and natural gas. About 46 different types of plastics are used in consumer products, and some products contain several kinds of plastic.
9 Billion
Number of tons of plastic produced since 1950
Since 1950, humans have produced 8.3 billion metric tons (9 billion tons) of plastic, half of it in the last 14 years. Over 90% of the plastic that the world has produced since 1950 has not been recycled. About 76% of this plastic has been thrown away and takes hundreds to thousands of years to degrade.
Only 9.5% of the plastic waste in the United States is recycled according to the EPA. The other 90.5% of U.S. plastic wastes is burned or buried in landfills or litters the land and oceans (see
Figure 20.15
). Plastic recycling percentages are low because there are many different types of plastic resins, which are difficult to separate from products that contain several types of plastic. Another factor is that most plastic beverage containers and other plastic products are not designed for recycling. However, progress is being made in the development of more degradable bioplastics (
Science Focus 21.2
).
Science Focus 21.2
Bioplastics
Henry Ford, who developed the first Ford car and founded Ford Motor Company, supported research on the development of a bioplastic made from soybeans and another made from hemp. A 1914 photograph shows him using an ax to strike the body of a Ford car made from soy bioplastic to demonstrate its strength and resistance to denting. However, as oil became cheaper and widely available, petrochemical plastics took over the market.
Now, confronted with climate change and other environmental problems associated with the use of oil and other fossil fuels, chemists are stepping up efforts to make more environmentally sustainable plastics. These bioplastics can be made from plants such as corn, soy, sugarcane, switchgrass, chicken feathers, and some components of garbage.
Compared with conventional oil-based plastics, properly designed bioplastics are lighter, stronger, and cheaper. In addition, making them usually requires less energy and produces less pollution per unit of weight. Instead of being sent to landfills, some packaging made from bioplastics can be composted to produce a soil conditioner, in keeping with the chemical cycling principle of sustainability.
Some bioplastics are more environmentally friendly than others. For example, some are made from corn raised by industrial agricultural methods, which require great amounts of energy, water, and petrochemical fertilizers and thus have a large ecological footprint. In evaluating and choosing bioplastics, scientists urge consumers to learn how they were made, how long they take to biodegrade, and whether they degrade into harmful chemicals.
Critical Thinking
1. Do you think that the advantages of bioplastics outweigh their disadvantages?
Engineer Mike Biddle developed a 16-step automated commercial process for recycling high-value plastics. It separates plastic items from nonplastic items in mixed solid waste, separates plastic types from one another, and converts them to pellets that can be sold and used to make new plastics products. For his work, Biddle has been named a Technology Pioneer by the World Economic Forum and has received some of the world’s most important environmental rewards. However, the process is costly and depends on free access to plastic wastes in the United States and the European Union. Because of a lack of access to such wastes, Biddle has had to abandon his efforts to recycle plastic wastes.
In 2017, researchers from Britain’s University of Portsmouth and the U.S. Department of Energy’s National Renewable Energy Laboratory accidentally developed an enzyme that can breakdown polyethylene terephthalate or PET, used in plastic bottles that litter the land and oceans. Researchers are working to speed up the decomposition process and to evaluate any harmful effects of the decomposition products.
21.3gRecycling Has Advantages and Disadvantages
Figure 21.12
lists the advantages and disadvantages of recycling.
Figure 21.12
Recycling solid waste has advantages and disadvantages.
Critical Thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
Photo: Jacqui Martin/ Shutterstock.com
Critics of recycling programs argue that recycling is costly and adds to the taxpayer burden in communities where recycling is funded through taxation. Proponents of recycling point to studies showing that the net economic, health, and environmental benefits of recycling (
Figure 21.12, left) far outweigh the costs. The EPA estimates that each year, recycling and composting in the United States reduce emissions of climate-changing carbon dioxide by an amount roughly equal to that emitted by 36 million passenger vehicles. In addition, the U.S. recycling industry employs 1.25 million people and doubling the U.S. recycling rate would create about 1 million new jobs. (However, such growth could be in doubt. See the Case Study that follows.) Recycling steel, aluminum, copper, lead, and paper products can save 65–95% of the energy needed to make these products from virgin materials, and recycling plastics saves twice the amount of energy produced by burning them in an incinerator.
Case Study
A Threat to U.S. Recycling
For years, the United Sates has been selling about 40% of the solid wastes it has collected to China for use as raw materials in manufacturing the products it sells throughout the world. However, in 2018, China—the world’s largest buyer of collected U.S. solid wastes—banned imports of mixed paper and many types of plastic wastes and e-wastes and tightened contamination standards for material it will still accept. The reason for this partial ban is that many of the wastes that China bought from the United States had mixtures of nonrecyclable materials, food wastes, and other contaminants, some of them hazardous, that were expensive to remove, mostly by hand.
U.S. recycling companies used to make money by selling recyclable material to China and other countries. Now they have to pay someone to take away and dispose of many of these materials. As a result, a significant amount of the materials collected in the United States for recycling is being incinerated or sent to landfills. U.S. scrap dealers are trying to find other countries that will buy recyclable materials, but the Chinese market for these materials is so large that it is hard to replace.
The result is less recycling in the United States. Recycling only works when there is someone to buy the materials people put in recycling bins. As a result, local governments that have curbside pickup of recyclables are now earning less, if anything, by selling the collected materials to recycling companies. If recycling in the United States declines, this will lead to increased air and water pollution, including emissions of greenhouse gases. This would be a setback for implementing the chemical cycling principle of sustainability.
Eventually, the Chinese ban on contaminated waste materials could benefit the U.S. recycling industry because domestic markets for recycled materials have also had to deal with contaminated materials. This will involve educating homeowners and businesses not to contaminate material picked up for recycling. It could mean the end of programs that take mixed recyclable materials and the growth of programs that require homeowners and business to separate recyclables into separate bins for paper, glass, metals, plastics, and composting. However, according to a 2019 Harris poll, 66% of the people surveyed said they would not recycle anything if it was not easy to do.
Cities that make money by recycling and that have higher recycling rates tend to use a single-pickup system for both recyclable and nonrecyclable materials, instead of a more expensive two-truck system. Successful systems also use a pay-as-you-throw approach. They charge by weight for picking up trash but not for picking up recyclable or reusable materials, and they require citizens and businesses to sort their trash and recyclables by type, as Germany does. San Francisco, California, uses such a system and recycles, composts, or reuses 80% of its MSW.
21.4aBurning Solid Waste
Many communities burn their solid waste until nothing remains but fine, white-gray ash, which can then be buried in landfills. Heat released by burning trash can be used to heat water or interior spaces, or for producing electricity in facilities called waste-to-energy incinerators. Globally, MSW is burned in more than 800 waste-to-energy incinerators (
Figure 21.13
), 71 of them in the United States. Waste is burned at extremely high temperatures in a combustion chamber. Heat from the burning material is used to boil water and produce steam. The steam in turn drives a turbine that generates electricity. Combustion also produces wastes in the form of gases and ash. The gases must be filtered to remove pollutants before being released into the atmosphere and the hazardous ash must be treated and properly disposed of in landfills.
Figure 21.13
Solutions: A waste-to-energy incinerator with pollution controls burns mixed solid wastes and recovers some of the energy to produce steam to use for heating or producing electricity.
Critical Thinking:
1. Would you invest in such a project? Why or why not?
The United States incinerates 13% of its MSW. One reason for the low percentage is that in the past, incineration earned a bad reputation because of highly polluting and poorly regulated incinerators. However, the Clean Air Act of 1990 forced the industry to install advanced pollution control equipment. By contrast, Denmark incinerates over half of its MSW in state-of-the-art waste-to-energy incinerators and the European Union incinerates 28% of its MSW. However, all incinerators produce an ash that contains toxic chemicals and must be stored safely somewhere, essentially forever.
Figure 21.14
lists the advantages and disadvantages of using incinerators to burn solid waste. According to an EPA study, landfills emit more air pollutants than modern waste-to-energy incinerators. On the other hand, the resulting incinerator ash contains toxic chemicals that must be stored somewhere. In addition, many U.S. citizens, local governments, and environmental scientists remain opposed to waste incineration because incinerators require a large, steady stream of waste to be profitable. This high demand for burnable wastes undermines efforts to reduce solid waste, increase reuse and recycling, and implement cradle-to-cradle design (Figure 21.1).
Figure 21.14
Incinerating solid waste has advantages and disadvantages. These trade-offs also apply to the incineration of hazardous waste.
Critical Thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
Top: Ulrich Mueller/ Shutterstock.com. Bottom: Dmitry Kalinovsky/ Shutterstock.com.
21.4bBurying Solid Waste
In the United States, about 53% of all MSW, by weight, is buried in sanitary landfills, compared to 80% in Canada, 15% in Japan, and 4% in Denmark. In newer landfills, called
sanitary landfills
(
Figure 21.15
), solid waste is spread out in thin layers, compacted, and covered daily with a layer of clay or plastic foam. This process keeps the material dry, cuts down on odors, reduces the risk of fire, and keeps rats and other pest animals away from the wastes.
Figure 21.15
Solutions: A state-of-the-art sanitary landfill is designed to eliminate or minimize environmental problems that plague older landfills.
The bottoms and sides of well-designed sanitary landfills have strong double liners and containment systems that collect the liquids leaching from them. Some landfills also have systems for collecting methane, a potent greenhouse gas that is produced when the buried wastes decompose in the absence of oxygen. The collected methane can be burned as a fuel to generate electricity although this adds climate-changing to the atmosphere.
Learning from Nature
Mango Materials is a company seeking to turn methane and other waste biogases into biodegradable plastics. Products made of such plastics that are put into landfills would then degrade within the same cycle to be at least partially used again.
About one-third of average landfill consists of paper and plastic packaging material. Other common materials include yard waste, plastics, metals, wood, glass, and food waste. Some types of solid waste are not accepted at U.S. landfills. Examples are tires, waste oil, oil filters, items containing mercury such as compact fluorescent light bulbs and thermometers, electronics, and medical waste.
Figure 21.16
lists the advantages and disadvantages of using sanitary landfills to dispose of solid waste.
Figure 21.16
Using sanitary landfills to dispose of solid waste has advantages and disadvantages.
Critical Thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
Photo: ShutterPNPhotography/ Shutterstock.com
Another type of landfill is an
open dump
, essentially a field or large pit where garbage is deposited and sometimes burned (
Figure 21.17
). Open dumps are rare in more-developed countries, but are widely used near major cities in many less-developed countries (Figure 21.3). China disposes of much of its rapidly growing mountains of solid waste mostly in rural open dumps or in poorly designed and poorly regulated landfills.
Figure 21.17
Some open dumps, especially in less-developed countries, are routinely burned, releasing large quantities of pollutants into the atmosphere. They can burn for days or weeks.
WitthayaP/ Shutterstock.com
Open dumps pose a variety of health, safety, and environmental threats, especially for poor people who survive by picking out metals and other valuable items to sell (
Figure 21.3). Leachates leaking from open dumps can contaminate soil and groundwater supplies.
21.5aHazardous Waste Requires Special Handling
Figure 21.18
shows an integrated hazardous waste management approach suggested by the U.S. National Academy of Sciences. It establishes three priority levels for dealing with hazardous waste: produce less; convert as much of it as possible to less-hazardous substances; and put the rest in long-term, safe storage. Denmark follows these priorities, but most countries do not.
Figure 21.18
Integrated hazardous waste management: The U.S. National Academy of Sciences has suggested these priorities for dealing with hazardous waste.
Critical Thinking:
1. Why do you think most countries do not follow these priorities?
As with solid waste, the top priority for hazardous waste management should be pollution prevention and waste reduction. Using this approach, industries try to find substitutes for toxic or hazardous materials. Then they reuse or recycle the hazardous materials they use within industrial processes, whenever possible. They may also sell their hazardous wastes as raw materials for making other products, in keeping with the cradle-to-cradle approach (Core Case Study).
At least 33% of industrial hazardous wastes produced in the European Union are exchanged through clearinghouses where they are sold as raw materials for use by other industries, in keeping with the chemical cycling principle of sustainability. The producers of these wastes do not have to pay for their disposal and recipients get low-cost raw materials. About 10% of the hazardous waste in the United States is exchanged through such clearinghouses, an amount that could be increased significantly. E-waste can also be recycled because it contains valuable materials (see Case Study that follows).
Case Study
Recycling E-Waste
In some countries, workers in e-waste recycling operations—many of them children (
Figure 21.19
)—are often exposed to toxic chemicals as they dismantle the electronic trash to extract its valuable metals or other parts that can be sold for reuse or recycling.
Figure 21.19
This young girl in Dhaka, Bangladesh, is recycling batteries by hammering them apart to extract tin and lead. The workers at this shop are mostly women and children.
James P. Blair/National Geographic Image Collection
Workers who recycle e-wastes in these countries usually wear no masks or gloves, often work in rooms with no ventilation, and are exposed to toxic chemicals. They carry out dangerous activities such as smashing TV picture tubes with large hammers to recover certain components—a method that releases large amounts of toxic lead dust into the air. They burn computer wires to expose copper. They also melt circuit boards in metal pots over coal fires to extract lead and other metals and douse the boards with strong acid to extract gold. After the metals are removed, leftover parts are often burned or dumped into rivers or onto the land.
The United States is the world’s largest producer of e-waste and in 2015 recycled about 31% of it (up from 19% in 2009). Since 2015, a total of 28 states and the District of Columbia have banned the disposal of computers and TV sets in landfills and incinerators. These measures set the stage for an emerging, highly profitable e-cycling industry. By 2016, 28 states along with New York City had laws requiring electronics manufacturers to take back their products for recycling. In 2016, Apple introduced Liam—a 29-armed robot capable of taking apart 1.2 million iPhones a year, saving components that can be recycled.
Some call for a U.S. federal law to institute a cradle-to cradle approach (
Core Case Study) that would require manufacturers to take back all electronic devices they produce and recycle them domestically. It could be similar to laws in the European Union, where a recycling fee typically covers the costs of such programs. Without such a law, there is little incentive for recycling e-waste and plastics.
While take-back programs are important, the only real long-term solution for reducing e-waste is a cradle-to-cradle approach (Core Case Study). Through such an approach, electrical and electronic products would be designed to be produced and easily repaired, remanufactured, or recycled, without the use of toxic materials.
Critical Thinking
1. Would you support a recycling fee on all electronic devices? Why or why not?
21.5bDetoxifying Hazardous Wastes
In Denmark, all hazardous and toxic wastes from industries and households are collected and delivered to transfer stations throughout the country. They are then taken to a large processing facility, where three-fourths of the waste is detoxified using physical, chemical, and biological methods. The rest is buried in a carefully designed and monitored landfill.
Examples of physical methods for detoxifying hazardous wastes include using charcoal or resins to filter out harmful solids, distilling liquid wastes to separate out harmful chemicals, and precipitating such chemicals from solution. Especially deadly wastes, such as those contaminated by mercury, can be encapsulated in glass, cement, or ceramics and put in secure storage sites. Chemical methods are used to convert hazardous chemicals to harmless or less harmful chemicals through chemical reactions.
Some scientists and engineers consider biological methods for treatment of hazardous waste to be the wave of the future. One approach is bioremediation, in which bacteria and enzymes are used to destroy toxic or hazardous substances or to convert them to harmless compounds. Bioremediation is often used on soil contaminated with hazardous chemicals, such as PCBs, pesticides, and oil. Bioremediation usually takes longer to work than most physical and chemical methods, but costs much less.
Phytoremediation is another biological method for treating hazardous wastes. It involves using natural or genetically engineered plants to absorb, filter, and remove contaminants from polluted soil and water. Phytoremediation can be used to clean up soil and water contaminated with chemicals such as pesticides, organic solvents, and radioactive or toxic metals. This method is still being evaluated and is slow compared to other alternatives.
Hazardous wastes can also be incinerated to break them down and convert them to harmless or less harmful chemicals. This has the same advantages and disadvantages as incinerating solid wastes (Figure 21.14). Incinerating hazardous waste without effective and expensive air pollution controls can release air pollutants such as highly toxic dioxins. It also produces a highly toxic ash that must be safely and permanently stored in a specially designed landfill or vault.
Plasma gasification is another thermal treatment method that uses arcs of electrical energy to produce very high temperatures to vaporize trash in the absence of oxygen. The process reduces the volume of a given amount of waste by 99%, produces a synthetic gaseous fuel, and encases toxic metals and other materials in glassy lumps of rock. It is currently very costly, but plasma arc companies are working to bring prices down.
Figure 21.20
lists the major advantages and disadvantages of using this process.
Figure 21.20
Using plasma gasification to detoxify hazardous wastes has advantages and disadvantages.
Critical Thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
21.5cStoring Hazardous Waste
After reduction, reuse, and recycling options have been pursued (Figure 21.18), remaining hazardous waste can be buried on land or stored long-term in secure vaults. In reality, burial is the most widely used method in the United States and in most countries, largely because of its lower cost.
The most common form of burial is deep-well disposal in which liquid hazardous wastes are pumped under very high pressure through a pipe into dry, porous rock formations deep underground. The rock formations lie far beneath aquifers that are tapped for drinking and irrigation water. Theoretically, these liquids soak into the porous rock material and are isolated from overlying groundwater by essentially impermeable layers of clay and rock. The cost is low and the wastes can often be retrieved if problems develop.
However, there are a limited number of such sites and limited space within them. Sometimes the wastes leak into groundwater from the well shaft or migrate into groundwater in unexpected ways. Deep-well disposal also encourages the production rather than the reduction of hazardous waste.
In the United States, almost two-thirds of all liquid hazardous wastes are injected into deep disposal wells. This amount is increasing sharply with the use hydraulic fracking to produce natural gas and oil trapped in shale rock (
Figure 15.1
). Fracking produces large volumes of liquid hazardous waste, which when injected into deep disposal wells has the potential to contaminate groundwater and increase the risk of earthquakes (see
Science Focus 15.1
).
Many scientists view current regulations for deep-well disposal in the United States as inadequate (see the Case Study that follows).
Figure 21.21
lists the advantages and disadvantages of using deep-well disposal of liquid hazardous wastes.
Figure 21.21
Injecting liquid hazardous waste into deep underground wells has advantages and disadvantages.
Critical Thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
Case Study
Hazardous Waste Regulation in the United States
Several U.S. federal laws help regulate the management and storage of hazardous wastes. About 5% of all hazardous waste produced in the United State is regulated under the Resource Conservation and Recovery Act (RCRA), passed by the U.S. Congress in 1976 and amended in 1984.
Under RCRA, the EPA sets standards for the management of several types of hazardous waste. It also issues permits to companies that allow them to produce and dispose of a certain amount of those wastes by approved methods. Permit holders must use a cradle-to-grave system. This means tracking the transfer of waste from a point of generation (cradle) to an approved off-site disposal facility (grave), and submitting proof of this disposal to the EPA. RCRA is a good start, but 95% of the hazardous and toxic wastes produced in the United States, including e-waste, are not regulated.
Critical Thinking
1. Why do you think 95% of the hazardous waste produced in the United States is not regulated? Do you favor regulating such wastes? What do you think would be the economic consequences of doing so? Would this promote the cradle-to-cradle approach to reducing solid and hazardous wastes?
The Toxic Substances Control Act has also been in place since 1976. Its purpose is to regulate and ensure the safety of the thousands of chemicals used in the manufacturing of, or as ingredients in, many products. Under this law, companies must notify the EPA before introducing a new chemical into the marketplace, but they are not required to provide any data about its safety. In other words, any new chemical is viewed as safe unless the EPA can show it is harmful.
Under intense pressure from manufacturers, when the TSCA was passed in 1976, it allowed the approximately 62,000 chemicals then on the market to continue being used without being tested for safety. The law also made it very difficult for the EPA to demonstrate that a new chemical is hazardous enough to ban. In addition, the EPA has had limited funding for evaluating the safety of old or new chemicals.
As a result, since 1976, the EPA has used this act to ban only 5 of the at least 85,000 chemicals now in use. In 2016, Congress revised the TSCA, requiring the EPA to:
· Review all existing and new chemicals, identify those that pose unreasonable risks, and regulate or eliminate those risks;
· Quickly review chemicals known to persist in the environment and to build up in humans;
· Determine whether a new chemical meets certain safety standards before it enters the market;
· Consider a chemical’s effects on vulnerable populations such as infants, children, pregnant women, chemical workers, and the elderly; and
· Require companies to make data on their chemicals available.
These are helpful improvements but critics point out that the law does not require enough funding from the chemical industry for the EPA to evaluate thousands of chemicals. An analysis by the Environmental Working Group estimated that even with adequate funding, the EPA would need 28 years to evaluate the risks of 90 priority chemicals, 20 additional years to finalize regulations for those chemicals, and 35 more years to implement the resulting rules. The rules would then be subject to lengthy lawsuits from manufacturers. In other words, evaluating and regulating just 90 of the 85,000 chemicals in use under the 2016 update of this law will take an estimated 83 years.
In 1980, Congress passed the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as the Superfund Act and administered by the EPA. The goals of the act are to identify sites, called Superfund sites, where hazardous wastes have contaminated the environment (
Figure 21.25
), and to clean them up using EPA-approved methods. Superfund sites that represent an immediate and severe threat to human health are put on a National Priorities List and scheduled for the earliest possible cleanup.
Figure 21.25
Leaking barrels of toxic waste.
patrikslezak/Fotolia LLC
As of June of 2018, there were 1,338 sites on the Superfund list, along with 53 proposed new sites, and 412 sites had been cleaned up and removed from the list. The Waste Management Research Institute estimates that at least 10,000 sites should be on the priority list and that cleanup of these sites could cost about $1.7 trillion, not including legal fees. This shows why it is important to emphasize waste reduction and pollution prevention over the regulation and cleanup approach that the United States and most countries rely on.
In 1984, Congress amended the Superfund Act to give citizens the right to know what toxic chemicals are being stored or released in their communities. This required large manufacturing facilities to report their annual releases of any of nearly 650 toxic chemicals. If you live in the United States, you can find out what toxic chemicals are being stored and released in your neighborhood by going to the EPA’s Toxic Release Inventory website.
The Superfund Act, designed to make polluters pay for cleaning up abandoned hazardous waste sites, greatly reduced the number of illegal dumpsites around the country. It also forced waste producers fearful of liability claims to reduce their production of such waste and to recycle or reuse much more of it. However, in 1995, under pressure from polluters, the U.S. Congress did not renew the tax on oil and chemical companies, which financed the Superfund legislation. Since then, taxpayers, not polluters, have been paying for cleanups (with an average cost of $26 million) when responsible parties cannot be found. In addition, cleanups are taking longer, which increases the risks from environmental spills. Under pressure from polluters, Congress has not changed the act to make polluters pay—a key to the success of the original act.
Closely associated with CERCLA is the EPA’s Brownfields Program. A brownfield is an industrial or commercial property that is, or may be, contaminated with hazardous pollutants. The program is designed to help states, communities, and other stakeholders economically redevelop contaminated property. The program assists interested parties in assessing sites, cleaning up sites, or reusing land designated as a brownfield. Reclaiming these lands can increase local tax bases, promote job growth, enable a new facility to use existing infrastructure, and keep undeveloped land from being used.
Some liquid hazardous wastes are stored in lined ponds, pits, or lagoons, called surface impoundments. Sometimes impoundments include liners to help contain the waste. Where liners are not used or when liners leak, the concentrated wastes can seep into groundwater. Studies conducted by the EPA found that 70% of all U.S. hazardous waste storage ponds lack liners and could threaten groundwater supplies. The EPA warns that eventually, all impoundment liners are likely to leak.
Because surface impoundments are not covered, harmful chemicals can evaporate and pollute the air. In addition, flooding from heavy rains and storms can cause such ponds to overflow. Not all U.S. hazardous waste storage ponds have liners, and many liners are subject to leaks that could eventually contaminate groundwater.
Figure 21.22
lists the advantages and disadvantages of using this method.
Figure 21.22
Storing liquid hazardous wastes in surface impoundments has advantages and disadvantages.
Critical thinking:
1. Which single advantage and which single disadvantage do you think are the most important? Why?
Some highly toxic materials (such as mercury; Chapter 17, Core Case Study) cannot be destroyed, detoxified, or safely buried. Some of these materials must be stored in carefully designed and monitored secure hazardous waste landfills (
Figure 21.23
). This is the least-used method because of the expense involved.
Figure 21.24
lists some ways in which you can reduce your output of hazardous waste—the first step in dealing with it.
Figure 21.23
Solutions: Hazardous wastes can be isolated and stored in secure hazardous waste landfills.
Figure 21.24
Individuals matter: You can reduce your output of hazardous wastes.
Critical Thinking:
1. Which two of these measures do you think are the most important ones to take? Why?
Learning from Nature
Scientists are studying microbes called diatoms, which build protective silica shells, in order to find substitutes for the toxic chemicals used in manufacturing silicon-based computer chips.
21.6aCitizen Action
In the United States, individuals have organized grassroots (bottom-up) campaigns to prevent the construction of hundreds of incinerators, landfills, treatment plants for hazardous and radioactive wastes, and chemical plants in or near their communities. These campaigns have organized sit-ins, concerts, and protest rallies. They have gathered signatures on petitions and presented them to lawmakers.
Health risks from incinerators and landfills, when averaged over the entire country, are quite low. However, the risks for people living near such facilities are higher. Manufacturers and waste industry officials point out that something must be done with the toxic and hazardous wastes created in the production of certain goods and services. They contend that even if local citizens adopt a “not in my back yard” (NIMBY) approach, the waste will always end up in someone’s back yard.
Many citizens do not accept this argument. Their view is that the best way to deal with most toxic and hazardous waste is to produce much less of it by focusing on pollution and waste prevention as suggested by the U.S. National Academy of Sciences (
Figure 21.18). They argue that the goal should be “not in anyone’s back yard” (NIABY) or “not on planet Earth” (NOPE).
21.6bInternational Treaties
For decades, some countries regularly shipped hazardous wastes to other countries for disposal or processing. Since 1992, an international treaty known as the Basel Convention has banned participating countries from shipping hazardous waste (including e-waste) through other countries without their permission.
By 2018, this agreement had been ratified (formally approved and implemented) by 183 countries. The United States has signed but has not ratified the convention. In 1995, the treaty was amended to outlaw all transfers of hazardous wastes from industrial countries to less-developed countries. This ban will help, but it will not do away with the highly profitable illegal shipping of hazardous wastes. Hazardous waste smugglers evade the laws by using an array of tactics, including bribes, false permits, and mislabeling of hazardous wastes as recyclable materials.
In 2001, delegates from 122 countries developed a global treaty known as the Stockholm Convention on Persistent Organic Pollutants (POPs). POPs are organic chemicals produced by manufacturers that persist in the environment. The treaty started by regulating the use of 12 widely used POPs that can accumulate in the fatty tissues of humans and other animals that occupy high trophic levels in food webs. Because they persist in the environment, POPs can also be transported long distances by wind and water.
The original list of 12 hazardous POPs chemicals, called the dirty dozen, includes DDT and eight other chlorine-containing persistent pesticides, PCBs, dioxins, and furans. Since then, other chemicals have been added. Based on blood tests and statistical sampling, medical researchers at New York City’s Mount Sinai School of Medicine concluded that nearly every person on earth likely has detectable levels of some POPs in their bodies, and the health effects of this presence are unknown. By 2016, 180 countries (not including the United States) had ratified a strengthened version of the treaty. The list of regulated POPs is expected to grow.
In 2000, the Swedish Parliament enacted a law that, starting in 2020, will ban all potentially hazardous chemicals that are persistent in the environment and that can accumulate in living tissue. This law also will require industries to perform risk assessments on the chemicals they use and to show that these chemicals are safe to use, as opposed to requiring the government to show that they are dangerous. In other words, chemicals are assumed to be guilty until proven innocent—the reverse of the current policy in the United States and most other countries. There is strong opposition to this approach in the United States, especially from most of the industries that produce and use potentially hazardous chemicals.
21.6cEncouraging Reuse and Recycling
Why don’t we have more reuse and recycling? First, these strategies must compete with the use of cheap, disposable products whose market prices do not include hidden harmful environmental and health costs. This is a violation of the full-cost pricing principle of sustainability.
Second, the economic playing field is uneven, because in most countries, resource extraction industries receive more government tax breaks and subsidies than reuse and recycling industries.
Third, the demand and thus the price paid for recycled materials fluctuates, mostly because it is not a high priority for most governments, businesses, and individuals to buy goods made of recycled materials.
How can we encourage reuse and recycling? Governments can increase subsidies and tax breaks for reusing and recycling materials, and decrease subsidies and tax breaks for making items from virgin resources.
Another strategy is to ramp up use of the fee-per-bag waste collection system that charges households for the trash they throw away by weight but not for their recyclable and reusable wastes. When Fort Worth, Texas, instituted such a program, the proportion of households recycling their trash went from 21% to 85%. The city went from losing $600,000 in its recycling program to making $1 million a year because of increased sales of recycled materials to industries.
One way to include some of the harmful environmental costs of products in their prices, while encouraging recycling, is to attach a small deposit fee to the price of recyclable items, as is done in many European countries, several Canadian provinces, and 10 U.S. states that have bottle bills. Such laws place a deposit fee of 5 or 10 cents on each beverage container, and consumers can recover that fee by returning their empty containers to the store. In states with bottle bills, 98% of bottles are recycled compared to a national average of roughly 33%.
Governments can also pass laws requiring companies to take back and recycle or reuse packaging and electronic waste discarded by consumers. Japan and some European Union countries have such laws. Another strategy is to encourage or require government purchases of recycled products to help increase the demand for and lower the prices of these products. Citizens can also pressure governments to require product labeling listing the recycled content of products, as well as the types and amounts of any hazardous materials they contain. This would help consumers to make more informed choices about the environmental consequences of buying certain products. It would also help to expand the market for recycled materials by spurring demand for them.
21.6eLow-Waste Economies
According to physicist Albert Einstein, “A clever person solves a problem; a wise person avoids it.” Many people are taking these words seriously. A growing number of school cafeterias, restaurants, national parks, and corporations are participating in a “zero waste” movement to reduce, reuse, and recycle, and some have lowered their waste outputs by up to 80%, with the ultimate goal of eliminating their waste outputs.
Many environmental scientists argue that we can prevent pollution, reduce waste, and make a transition to a low-waste economy by understanding and following these key principles:
1. Everything is connected.
2. There is no away, as in to throw away, for the wastes we produce.
3. Producers and polluters should pay for the wastes they produce.
4. We can mimic nature by reusing, recycling, composting, or exchanging most of the municipal solid wastes we produce (see the Case Study that follows).
Case Study
Industrial Ecosystems: Biomimicry
An important goal for a more sustainable society is to make its industrial manufacturing processes cleaner and more sustainable by redesigning them to mimic the way nature deals with wastes—an approach called biomimicry (see
Chapter 1, Core Case Study). According to the chemical cycling principle of sustainability, the waste outputs of one organism become the nutrient inputs of another organism, so that all of the earth’s nutrients are endlessly recycled. This explains why there is essentially no waste in nature.
One way for industries to mimic nature is to reuse or recycle most of the minerals and chemicals they use, instead of burying them or burning them or shipping them somewhere else. Industries can set up resource exchange webs, in which the wastes of one manufacturer become the raw materials for another. This approach is similar to food webs in natural ecosystems and is an application of the cradle-to-cradle concept (Core Case Study).
This is happening in Kalundborg, Denmark, where an electric power plant and nearby industries, farms, and homes are collaborating to save money and to reduce their outputs of waste and pollution within what is called an ecoindustrial park, or industrial ecosystem. They exchange waste outputs and convert them into resources, as shown in
Figure 21.26
. This cuts pollution and waste and reduces the flow of nonrenewable mineral and energy resources through the local economy.
Figure 21.26
Solutions: This industrial ecosystem in Kalundborg, Denmark, reduces waste production by mimicking a natural ecosystem’s food web. The wastes of one business become the raw materials for another, thus mimicking the way that nature recycles chemicals.
Ecoindustrial parks provide many economic benefits for businesses. By encouraging recycling and waste reduction prevention, they reduce the costs of managing solid wastes, controlling pollution, and complying with pollution regulations. They also reduce a company’s chances of being sued because of damages, to people or to the environment, caused by their actions. In addition, companies improve the health and safety of workers by reducing their exposure to toxic and hazardous materials, thereby reducing company health insurance costs. Biomimicry also encourages companies to come up with new, environmentally beneficial, and less resource-intensive chemicals, processes, and products that they can sell worldwide. Today, more than 100 such parks operate in various places around the world, including the United States and China, and more are being built.
Learning from Nature
The food web serves as a natural model for responding to the growing problems of solid and hazardous wastes. The ecoindustrial park and many applications of cradle-to-cradle design and manufacturing (
Core Case Study) follow this model.
Big Ideas
· The order of priorities for dealing with solid waste should be first to minimize production of it, then to reuse and recycle as much of it as possible, and finally to safely burn or bury what is left.
· The order of priorities for dealing with hazardous waste should be first to minimize production of it, to reuse or recycle it, to convert it to less-hazardous material, and to safely store what is left.
· We can view solid wastes as wasted resources, and hazardous wastes as materials that we want to avoid producing in the first place.
· Tying It All TogetherThe Cradle-to-Cradle Approach and Sustainability
·
· The cradle-to-cradle approach to design, manufacture, and use of materials is an important strategy for reducing the amount of solid and hazardous wastes we produce. By mimicking nature, this approach views all discarded materials and substances as nutrients that circulate within industrial and natural cycles. It also allows us the opportunity to convert the harmful environmental impacts of human activities to beneficial impacts. The challenge is to make the transition from an unsustainable high-waste, throwaway economy to a more sustainable low-waste, reducing–reusing–recycling economy as soon as possible.
·
Such a transition will require applying the six principles of sustainability. We can reduce our outputs of solid and hazardous waste by relying much less on fossil fuels and nuclear power (which produced long-term, hazardous radioactive wastes) while relying much more on renewable energy from the sun, wind, and flowing water. We can mimic nature’s chemical cycling processes by reusing and recycling materials as much as possible. Integrated waste management, which uses a diversity of approaches and emphasizes waste reduction and pollution prevention, is a way to mimic nature’s use of biodiversity and implement the cradle-to-cradle approach. Including more of the harmful environmental and health costs of the consumer economy in market prices helps apply the full-cost pricing principle of sustainability while encouraging people to refuse, reduce, reuse, and recycle. Doing this benefits the environment, creates new jobs and businesses capitalizing on the four Rs, and provides health and environmental benefits for us, thus finding win-win solutions. This could also lead to lower levels of resource use per person, and thus lower levels of solid and hazardous waste production. All these measures together would help us to pass along to future generations a world that is at least as livable as, or even more so than, the one we now enjoy.
Critical Thinking
1. Find three products that you regularly use that could be made using cradle-to-cradle design and manufacturing (Core Case Study). For each of these products, sketch out a rough plan for how you would design and build it so that its parts could be reused many times or recycled in such a way that they would not harm the environment.
2. Do you think that manufacturers of computers, television sets, cell phones, and other electronic products should be required to take their products back at the end of their useful lives for repair, remanufacture, or recycling in a manner that is environmentally responsible and that does not threaten the health of recycling workers? Explain. Would you be willing to pay more for these products to cover the costs of such a take-back program? If so, what percentage more per purchase would you be willing to pay for these products?
3. Think of three items that you regularly use once and then throw away. Are there reusable items that you could use in place of these disposable items? For each item, calculate and compare the cost of using the disposable option for a year versus the cost of using the reusable alternative. Write a brief report summarizing your findings.
4. Do you think that you could consume less by refusing to buy some of the things you regularly buy? If so, what are three of those things? Do you think that this is something you ought to do? Explain.
5. A company called Changing World Technologies has built a pilot plant to test a process it has developed for converting a mixture of discarded computers, old tires, turkey bones and feathers, and other wastes into oil by mimicking and speeding up natural processes for converting biomass into oil. Explain how this recycling process, if it turns out to be technologically and economically feasible, could lead to increased waste production.
6. Would you oppose having
1. a sanitary landfill,
2. a hazardous waste surface impoundment,
3. a hazardous waste deep-injection well, or
4. a solid waste incinerator in your community? For each of these facilities, explain your answer. If you oppose having such facilities in your community, how do you think the solid and hazardous wastes generated in your community should be managed?
7. How does your school dispose of its solid and hazardous wastes? Does it have a recycling program? How well does it work? Does your school encourage reuse? If so, how? Does it have a hazardous waste collection system? If so, describe it. List three ways in which you would improve your school’s waste reduction and management systems.
8. Congratulations! You are in charge of the world. List the three most important components of your strategy for dealing with
1. solid waste and
2. hazardous waste.
9. Doing Environmental Science
10. Collect the trash (excluding food waste) that you generate in a typical week. Measure its total weight and volume. Sort it into major categories such as paper, plastic, metal, and glass. Then weigh each category and calculate its percentage by weight of the total amount of trash that you have measured. What percentage by weight of this waste consists of materials that could be recycled? What percentage consists of materials for which you could have used a reusable substitute, such as a coffee mug instead of a disposable cup? What percentage by weight of the items could you have done without? Compare your answers to these questions with those of your classmates. Together with your classmates, combine all the results and do the same analysis for the entire class. Use these results to estimate the same values for the entire student population at your school.
11. Chapter Review
12. Ecological Footprint Analysis
13. Researchers estimate that the average daily municipal solid waste production per person in the United States is 2 kilograms (4.4 pounds). Use the data in the pie chart below to get an idea of a typical annual MSW ecological footprint for each American by calculating the total weight in kilograms (and pounds) for each category generated during 1 year . Calculate the annual MSW footprint per person for each category in the table below.
14. Composition of a typical sample of U.S. municipal solid waste, 2015.
15.
16. (Compiled by the authors using data from the U.S. Environmental Protection Agency.)
|
Waste Category |
Annual MSW Footprint per Person |
|
Paper and paperboard |
|
|
Yard trimmings |
|
|
Food |
|
| Plastics | |
|
Metals |
|
|
Wood |
|
|
Rubber, leather, and textiles |
|
| Glass | |
|
Other/miscellaneous |
21.1a
Solid Waste Is Piling
Up
Think about what you have tossed in the trash today. Perhaps it was
leftovers from lunch, an empty can or plastic bottle, or something you no
longer needed. People throw away all sorts of items, and they all add up to
huge amounts of solid waste.
In the natural world, there is essentially no waste because the wastes
of one
organism become nutrients or raw materials for others in food
chains and food webs. This natural cycling of nutrients is the basis of the
chemical cycling
principles of sustainability
We violate this principle by producing huge amounts of waste materials
that are burned or buried in landfills or that end up as litter. For example,
the manufacturing of a desktop computer requires 700 or more different
materials obtained from mines, oil wells, and chemical factories all over the
world. For every 0.5 kilogram
(1 pound) of electronics it contains,
approximately 3,600 kilograms (8,000 pounds) of waste were created
—
an
amount roughly equal to the weight of a large pickup truck.
Because of the law of conservation of matter (
Chapter 2
,
Law of
Conservation of Matter
) and the nature of human lifestyles, we will always
produce some waste. However, studies and experience indicate that by
mimicking nature, through strategies such as cradle
–
to
–
cradle design (
Core
Case Study
), we could reduce this waste of potential resources and the
resulting environmental harm by up to 80%.
One major category of waste is
solid waste
—
any unwanted or discarded
material people produce that is not a liquid or a gas. There are two major
types of solid waste. The first is
industrial solid waste
produced by mines,
farms, and industries that supply us with goods
and services. The second
is
municipal solid waste (MSW)
, often called
garbage
or
trash
. It consists
of the combined solid wastes produced by homes and workplaces other
than factories. Examples of MSW include paper, cardboard,
food wastes,
cans, bottles, yard wastes, furniture, plastics, glass, wood, and electronics
or
e
–
waste
(see chapter
–
opening photo).
Much of the world’s MSW ends up as litter in rivers, lakes, the ocean, and
natural landscapes (
Figure 21.2
). One of the major symbols of such waste is
the single
–
use plastic bag. Laid end
–
to
–
end, the 100 billion plastic bags used
in the United States each year would reach to the moon and back 60 times.
In many countries, the landscape, lakes, and r
ivers are littered with plastic
bags, as are the oceans. Plastic bags can take 400 to 1,000 years to degrade.
21.1aSolid Waste Is Piling
Up
Think about what you have tossed in the trash today. Perhaps it was
leftovers from lunch, an empty can or plastic bottle, or something you no
longer needed. People throw away all sorts of items, and they all add up to
huge amounts of solid waste.
In the natural world, there is essentially no waste because the wastes
of one organism become nutrients or raw materials for others in food
chains and food webs. This natural cycling of nutrients is the basis of the
chemical cycling principles of sustainability
We violate this principle by producing huge amounts of waste materials
that are burned or buried in landfills or that end up as litter. For example,
the manufacturing of a desktop computer requires 700 or more different
materials obtained from mines, oil wells, and chemical factories all over the
world. For every 0.5 kilogram (1 pound) of electronics it contains,
approximately 3,600 kilograms (8,000 pounds) of waste were created—an
amount roughly equal to the weight of a large pickup truck.
Because of the law of conservation of matter (Chapter 2, Law of
Conservation of Matter) and the nature of human lifestyles, we will always
produce some waste. However, studies and experience indicate that by
mimicking nature, through strategies such as cradle-to-cradle design (Core
Case Study), we could reduce this waste of potential resources and the
resulting environmental harm by up to 80%.
One major category of waste is solid waste—any unwanted or discarded
material people produce that is not a liquid or a gas. There are two major
types of solid waste. The first is industrial solid waste produced by mines,
farms, and industries that supply us with goods and services. The second
is municipal solid waste (MSW), often called garbage or trash. It consists
of the combined solid wastes produced by homes and workplaces other
than factories. Examples of MSW include paper, cardboard, food wastes,
cans, bottles, yard wastes, furniture, plastics, glass, wood, and electronics
or e-waste (see chapter-opening photo).
Much of the world’s MSW ends up as litter in rivers, lakes, the ocean, and
natural landscapes (Figure 21.2). One of the major symbols of such waste is
the single-use plastic bag. Laid end-to-end, the 100 billion plastic bags used
in the United States each year would reach to the moon and back 60 times.
In many countries, the landscape, lakes, and rivers are littered with plastic
bags, as are the oceans. Plastic bags can take 400 to 1,000 years to degrade.
Livingin the Environment (MindTap Course List)
20th Edition
ISBN-13: 978-0357142202, ISBN-10: 0170291502
Compose
a 300
–
word
(
minimum
)
essay on the topic below. Essays must be double
–
spaced
and use
A
PA
–
style in
–
text citations to reference ideas or quotes that are not your own. You
must include a separate bibliography.
What would be accomplished if government
s passed laws requiring manufacturers to
take back and reuse or recycle all packaging waste, appliances, electronic equipment,
and motor vehicles at the end of their useful lives? Would you support such a law?
Explain why or why not.
You should cite and
quote from assigned readings, AVP’s, videos, and module activities to
support the ideas in your essay.
(A
link tha
t was in this weeks reading
)
https://www.nobelprize.org/mediaplayer/?id=796&view=1
Compose a 300
–
word (minimum) essay on the topic below. Essays must be double
–
spaced
and use APA
–
style in
–
text citations to reference ideas or quotes that are not your own. You
must include a separate bibliography.
What would be accomplished if government
s passed laws requiring manufacturers to
take back and reuse or recycle all packaging waste, appliances, electronic equipment,
and motor vehicles at the end of their useful lives? Would you support such a law?
Explain why or why not.
You should cite and
quote from assigned readings, AVP’s, videos, and module activities to
support the ideas in your essay.
(
A
link tha
t was in this weeks reading
)
https://www.nobelprize.org/mediaplayer/?id=796&view=1
Compose a 300-word (minimum) essay on the topic below. Essays must be double-spaced
and use APA-style in-text citations to reference ideas or quotes that are not your own. You
must include a separate bibliography.
What would be accomplished if governments passed laws requiring manufacturers to
take back and reuse or recycle all packaging waste, appliances, electronic equipment,
and motor vehicles at the end of their useful lives? Would you support such a law?
Explain why or why not.
You should cite and quote from assigned readings, AVP’s, videos, and module activities to
support the ideas in your essay.
(A link that was in this weeks reading)https://www.nobelprize.org/mediaplayer/?id=796&view=1
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Formatting
Title Page
Citation
Outline
