APES CH21 Overview

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Chapter 21
Solid and Hazardous Waste
Chapter Outline
CORE CASE STUDY E-Waste—An Exploding Problem
21-1 What Are Solid Waste and Hazardous Waste, and Why Are They Problems?
CASE STUDY Solid Waste in the United States
SCIENCE FOCUS Garbology and Tracking Trash
21-2 How Should We Deal with Solid Waste?
21-3 Why Are Refusing, Reducing, Reusing, and Recycling So Important?
Individuals matter Mike Biddle’s Contribution to Plastics Recycling
SCIENCE FOCUS Bioplastics
21-4 What Are the Advantages and Disadvantages of Burning or Burying Solid Waste?
21-5 How Should We Deal with Hazardous Waste?
CASE STUDY Recycling E-waste
CASE STUDY Hazardous Waste Regulation in the United States
21-6 How Can We Make the Transition to a More Sustainable Low-Waste Society?
CASE STUDY Industrial Ecosystems: Copying Nature
TYING IT ALL TOGETHER E-Waste and Sustainability
Key Concepts
21-A Solid waste contributes to pollution and includes valuable resources that could be reused or
recycled.
21-B Hazardous waste contributes to pollution, as well as to natural capital degradation, health problems,
and premature deaths.
21-2 A sustainable approach to solid waste is first to reduce it, then to reuse or recycle it, and finally to
safely dispose of what is left.
21-3 By refusing and reducing resource use and by reusing and recycling what we use, we decrease our
consumption of matter and energy resources, reduce pollution and natural capital degradation, and save
money.
21-4 Technologies for burning and burying solid wastes are well developed, but burning contributes to air
and water pollution and greenhouse gas emissions, and buried wastes eventually contribute to the
pollution and degradation of land and water resources.
21-5 A more sustainable approach to hazardous waste is first to produce less of it, then to reuse or recycle
it, then to convert it to less-hazardous materials, and finally to safely store what is left.
21-6 Shifting to a low-waste society requires individuals and businesses to reduce resource use and to
reuse and recycle wastes at local, national, and global levels.
Key Questions and Concepts
CORE CASE STUDY: E-waste - an exploding problem. E-waste consists of discarded computers and
other electronic waste. E-waste contains many valuable metals as well as toxic pollutants. Much of this
waste is transferred from the developed world to the developing world, particularly China. Efforts are
underway to stop this trade, as well as encourage recycling.
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21-1 What Are Solid Waste and Hazardous Waste, and Why Are They Problems?
A. Solid waste is any discarded material that is not liquid or gas.
1. Industrial solid waste is produced by mines, agriculture, and industry.
2. Municipal solid waste (MSW) is produced by homes and workplaces.
B. Hazardous or toxic waste is poisonous, reactive, corrosive, or flammable.
1. Includes radioactive waste.
CASE STUDY: Solid waste in the United States. The United States has 4.6% of the world’s
population but produces about one-third of the world’s solid waste. The U.S. leads the world in trash
production per person.
SCIENCE FOCUS: Garbology and tracking trash. Garbologists study the composition of
landfills in the fashion of archaeologists. They have found that items in landfills can resist
decomposition for long periods of time due to compaction.
21-2 How Should We Deal with Solid Waste?
A. One method to reduce waste and pollution is to implement waste management. This high-waste
approach accepts waste production as a result of economic growth.
1. It attempts to reduce environmental harm.
2. It transfers the waste from one part of the environment to another.
B. One method is waste reduction. This low-waste approach sees solid waste as a potential resource,
which should be reused, recycled, or composted.
1. It discourages waste production in the first place.
2. It encourages waste reduction and prevention.
C. Waste reduction is based on the three Rs:
1. Reduce, reuse, and recycle.
D. To cut waste production and promote sustainability, we must reduce consumption and redesign
our products. These are the six priorities for doing so.
1. Redesign manufacturing processes and products to use less material and energy.
2. Develop products that are easily repaired, reused, remanufactured, composted, or recycled.
3. Eliminate or reduce unnecessary packaging.
4. Fee-per-bag system of waste collection.
5. Cradle to grave responsibility.
6. Restructure urban transportation systems.
21-3 Why Are Refusing, Reducing, Reusing and Recycling So Important?
A. Reusing products helps reduce resource use, waste, and pollution; it also saves money.
1. Developing countries reuse their products; but there is a health hazard for the poor.
B. Recycling collects waste materials, turns them into useful products, and sells the new products.
1. Recycling is one of two types—it involves reprocessing discarded solid materials into new,
useful products; secondary recycling involves converting materials into different products.
2. Pre-consumer/internal waste is generated from a manufacturing process that is recycled. Postconsumer/external waste is generated by consumer use of products.
C. Solid waste recycling can be done in a materials-recovery facility (MRF). The wastes are
recycled and/or burned to produce energy; but such plants are expensive. They also must process
a large input of garbage.
D. Source separation recycling relies on households and businesses to separate their trash; these are
collected and sold to other dealers.
1. This produces less air and water pollution.
2. This method has less startup costs and operating costs.
3. It saves more energy and provides more jobs than MRFs.
Instructor's Manual: Chapter 21
4. Pay-as-you-throw (PAUT) waste collection systems charge for the mixed waste that is picked
up, but not for the recycled, separated materials.
E. Composting biodegradable organic wastes is a great way to mimic nature.
F. Factors that hinder reuse and recycling are:
1. The cost of a product does not include harmful environmental health costs in its life cycle.
2. Resource-extracting industries receive government tax breaks and subsidies while recycle and
reuse industries do not.
3. The demand and price for recycled materials fluctuates so there is less interest in committing
to this method.
SCIENCE FOCUS: Bioplastics. Most of today’s plastics are derived from petrochemicals.
However, bioplastics date back to the early 1900s. Environmental problems associated with oil have
triggered a renewed interest in bioplastics. One advantage of bioplastics is that they have the
potential to be composted.
21-4 What Are the Advantages and Disadvantages of Burning or Burying Solid Waste?
A. Municipal solid waste is burned in waste-to-energy incinerators, which produce steam for heating
or producing electricity.
B. The advantages and disadvantages of burning solid waste are: (given in Figure 24-13)
1. High operating costs.
2. Air pollution concerns.
3. Citizen opposition to the process.
C. Most solid waste is buried in landfills, which will leak toxic liquids into the soil and water.
1. Open dumps in the ground hold garbage; sometimes these are covered with dirt.
2. Sanitary landfills spread the solid waste out in thin layers, compact it, and cover it daily with
clay/plastic foam. Modern landfills line the bottom with an impermeable liner, which collects
leachate; rainwater is contaminated as it percolates through the solid waste. The leachate is
collected, stored in tanks and then sent to a sewage treatment plant. But all landfills will
eventually leak contaminants.
21-5 How Should We Deal with Hazardous Waste?
A. Three levels of priority for dealing with hazardous waste: produce less, convert to less hazardous
substances, and put the rest in long-term safe storage.
CASE STUDY: Recycling e-waste. More than 70% of the world’s e-waste ends up in China. Over
30,000 workers toil in unsafe conditions and are exposed to toxins. Some computer companies now
offer recycling, though only 18% of the e-waste in the U.S. is recycled, 80% of which is shipped
overseas.
B. Chemical and biological methods can be used to reduce the toxicity of hazardous wastes or to
remove them.
1. One biological treatment, bioremediation, uses bacteria and enzymes to help destroy
hazardous or toxic substances. They are converted to harmless compounds in the process.
2. Phytoremediation uses natural or genetically engineered plants to absorb, filter, and remove
contaminants from polluted water and soil.
C. Hazardous waste can be incinerated to break them down and convert them to less harmful
chemicals.
D. Burial on land is the most widely used method in the United States.
1. Deep-well disposal: liquid hazardous waste is pumped into porous rock formations beneath
aquifers.
2. Surface impoundments: ponds that are lined.
3. Some highly toxic materials cannot be detoxified, destroyed, or safely buried. Reducing their
use it the best solution.
4. Secure hazardous waste landfills: Hazardous wastes are put into containers and monitored.
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CASE STUDY: Hazardous waste regulation in the United States. The Resource Conservation
and Recovery Act (RCRA) regulates about 5% of the U.S. hazardous waste. The Comprehensive
Environmental Response, Compensation, and Liability Act (CERLA/Superfund program) was
passed in 1980. The law identifies hazardous waste sites and provides for cleanup of these sites on a
priority basis. The worst sites go on a National Priorities List (NPL) and are scheduled for total
cleanup. There are also laws that provide for cleaning up brown fields, abandoned sites contaminated
with hazardous wastes like factories, gas stations, junkyards, etc.
21-6 How Can We Make the Transition to a More Sustainable Low-Waste Society?
A. Individuals have organized to protest the construction of many treatment and storage facilities.
B. Environmental justice means that every person is entitled to protection from environmental
hazards regardless of race, gender, age, national origin income, social class, or any other factors.
1. Studies show that a disproportionate share of polluting facilities are located in minority
communities.
C. The Basel Convention is an international treaty banning developed countries from shipping
hazardous waste to other countries without their permission.
D. In 2000, a global treaty to control 12 persistent organic pollutants (POPs) was developed. To be
made effective, 50 countries must ratify the treaty.
1. POPs are toxic chemicals stored in the fatty tissue of humans and other organisms.
2. Twelve chemicals, the dirty dozen, need to be phased out, detoxified, and/or isolated.
E. To transition to a low-waste society, we need to understand that:
1. Everything is connected.
2. There is no place to send wastes “away.”
3. Polluters and producers should pay for the wastes they produce.
4. We should mimic nature by reusing/recycling the materials that we use.
CASE STUDY: Industrial ecosystems: copying nature. Biomimicry is the science and art of
discovering and using natural principles to solve human problems. An important goal for a more
sustainable society is to make its industrial manufacturing processes cleaner and more sustainable by
redesigning them to mimic how nature deals with wastes.
Teaching Tips
Large Lecture Courses:
Bring a list of items that can be recycled in your local community, either curb-side or at special locations
or facilities. Ask you students to first brainstorm all of the products that are recyclable. Then question
them about items that may remain on the list (for example, motor oil or batteries). Next get them to
generate ideas as to why some of these items are not recycled when they are indeed recyclable. Are
people not aware? Is it too difficult or time-consuming?
Smaller Lecture Courses:
Suppose a large city is looking to develop a landfill either near your town, or near a valued location in
your vicinity. An example would be the landfill that the city of Los Angeles has tried for years to develop
on the border of Joshua Tree National Park. Remind students that places like New York City ship their
garbage quite far away, so it does not matter if there is no metropolis in your region. Have the students
divide on the issue and debate whether or not: (a) the landfill should be developed, and (b) cities should
be allowed to ship their trash to other locations. What are the alternatives?
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Key Terms
biomimicry
environmental justice
hazardous (toxic) waste
industrial solid waste
integrated waste management
municipal solid waste
open dump
primary recycling
recycle
reduce
reuse
sanitary landfills
secondary recycling
solid waste
waste management
waste reduction
Term Paper Research Topics
1.
Solid waste: what should NYC do with its solid waste?
2.
Epidemiology studies of different hazardous substances such as lead and dioxins.
3.
Alternatives to hazardous chemicals.
4.
The history of synthetic organic chemicals.
5.
Individual: reduce, reuse, recycle, rethink; garage sales; source separation of household wastes;
appliances built to last; what consumers can do about excessive packaging; recycling centers;
resource recovery plants: the Saugus model; reduction of lead exposure; reduction of dioxins in the
environment; businesses that have invested in pollution prevention.
6.
City/county: municipal resource recovery plants; recycling industrial wastes; scrapyards; antilitter
campaigns; hazardous-waste landfills; hazardous-waste incineration; deep-well disposal.
7.
State: bottle bills.
8.
National Policy: Resource Conservation and Recovery Act; Superfund; strategies for treating
hazardous chemicals; strategies for recycling hazardous chemicals; strategies for preventing
hazardous chemicals; the ecojustice movement; Not On Planet Earth.
9.
International: recycling programs in Sweden and Switzerland; Germany's tough packaging law; the
international hazardous-waste trade.
Discussion Topics
1.
Trace the roots of the throwaway mentality.
2.
Should disposable goods and built-in obsolescence be discouraged by legislation and economic
means (such as taxes)?
3.
Are solid waste landfills the least desirable solution to our solid waste disposal problem?
4.
Should urban incinerators be encouraged as an alternative to sanitary landfills?
5.
Should more substances be regulated as hazardous wastes?
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6.
What benefits did we gain as a society for the lead effects we have suffered?
7.
Should the precautionary principle prevail?
Instructor's Manual: Chapter 21
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