CHAPTER 21

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e- waste

ends up in landfills and incinerators. It includes high- quality plastics and valuable metals such as aluminum, copper, nickel, platinum, silver, and gold. E- waste is also a source of toxic and hazardous pollutants, including polyvinylchloride ( PVC), brominated flame retardants, lead, and mercury, which can contaminate air, surface water, groundwater, and soil and cause serious health problems and even early death for e- waste workers.

About 98.5% of all solid waste produced in the United States is industrial solid waste

from mining (76%), agriculture (13%), and industry (9.5%). The remaining 1.5% of U.S. solid waste is municipal solid waste (MSW), the largest categories of which are paper and cardboard (33% of total U.S. MSW), yard waste (13%), food waste (13%), plastics (12%), and metals (8%). This 1.5% of the overall U.S. solid waste problem is still huge. Each year, the United States generates enough MSW to fill a bumper-to-bumper convoy of garbage trucks encircling the globe almost eight times! About 67% of it is dumped in landfills or incinerated, but much of it ends up as litter.

Post-consumer/external waste

generated by consumer use of products.

Pre-consumer/internal waste

generated from a manufacturing process that is recycled

Disadvantages of recycling solid waste include

include burying in areas with ample landfill space, may lose money for items such as glass and some plastics, reduces profits for landfill and incinerator owners, and source separation is inconvenient for some people.

Hazardous or toxic waste

is poisonous, reactive, corrosive, or flammable Includes radioactive waste Examples include industrial solvents, hospital medical waste, car batteries (containing lead and acids), household pesticide products, dry-cell batteries (containing mercury and cadmium), and ash from incinerators and coal-burning power plants.

Biomimicry

is the science and art of discovering and using natural principles to solve human problems

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.

Industrial solid waste

produced by mines, agriculture, and industry.

Secondary recycling involves

waste materials converted into different products. For example, used tires can be shredded and turned into rubberized road surfacing, and newspapers can be reprocessed into cellulose insulation.

Burial on land is the most widely used method in the United States

-Deep-well disposal: liquid hazardous waste is pumped into porous rock formations beneath aquifers. -Surface impoundments: ponds that are lined. -Some highly toxic materials cannot be detoxified, destroyed, or safely buried. Reducing their use it the best solution. -Secure hazardous waste landfills: Hazardous wastes are put into containers and monitored.

To transition to a low-waste society, we need to understand that:

-Everything is connected. -There is no place to send wastes "away." -Polluters and producers should pay for the wastes they produce. -We should mimic nature by reusing/recycling the materials that we use.

The advantages and disadvantages of burning solid waste are

-High operating costs. -Air pollution concerns. -Citizen opposition to the process.

Factors that hinder reuse and recycling are:

-The cost of a product does not include harmful environmental health costs in its life cycle. -Resource-extracting industries receive government tax breaks and subsidies while recycle and reuse industries do not. -The demand and price for recycled materials fluctuates so there is less interest in committing to this method.

Waste reduction is based on the three Rs:

1. Reduce, reuse, recycle.

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.

The advantages of incineration

are that it reduces trash volume, produces energy, and concentrates hazardous substances into ash for burial.

Three ways to reduce hazardous waste include

avoiding the use of pesticides and other hazardous chemicals, using less harmful and substances, and avoiding the disposal of pesticides, paints, solvents, oil, antifreeze, or other hazardous chemicals by flushing them down the toilet, pouring them down the drain, burying them, throwing them into the garbage, or dumping them down storm drains.

How can we encourage reuse and recycling?

Proponents say that leveling the economic playing field is the best way to start. Governments can increase subsidies and tax breaks for reusing and recycling materials (the carrot) and decrease subsidies and tax breaks for making items from virgin resources (the stick).

Solid waste

any discarded material that is not liquid or gas

Advantages of phytoremediation include

easy to establish, inexpensive, can reduce material dumped into landfills and produces little air pollution compared to incineration.

Primary, or closed-loop, recycling

involves materials being recycled into new products of the same type. For example, used aluminum cans are turned into new aluminum cans.

Municipal solid waste (MSW)

is produced by homes and workplaces

Reusing products helps

reduce resource use, waste, and pollution; it also saves money. -Developing countries reuse their products; but there is a health hazard for the poor.

The disadvantages of incineration

that the facilities are expensive to build, they produce hazardous waste, emits some CO2 and other air pollutants and they may encourages waste production

The second law of thermodynamics dictates

that we should be never mix different types of waste that we may want to separate later.

cradle-to-grave system

to keep track of waste they transfer from a point of generation (cradle) to an approved off-site disposal facility (grave), and they must submit proof of this disposal to the EPA.

bioremediation

uses bacteria and enzymes to help destroy hazardous or toxic substances. They are converted to harmless compounds in the process.

Phytoremediation

uses natural or genetically engineered plants to absorb, filter, and remove contaminants from polluted water and soil.

Municipal solid waste

burned in waste-to-energy incinerators, which produce steam for heating or producing electricity. Examples include paper and cardboard, food wastes, cans, bottles, yard wastes, furniture, plastics, metals, glass, wood, and e-waste.

To cut waste production and promote sustainability, we must reduce consumption and redesign our products. These are the six priorities for doing so.

-Redesign manufacturing processes and products to use less material and energy. -Develop products that are easily repaired, reused, remanufactured, composted, or recycled. -Eliminate or reduce unnecessary packaging. -Fee-per-bag system of waste collection. -Cradle to grave responsibility. -Restructure urban transportation systems.

open dumps

are essentially fields or holes in the ground where garbage is deposited and sometimes burned. They are rare in developed countries, but are widely used near major cities in many developing countries.

Bioplastics

are plastics made from biologically based chemicals

POPs

are toxic chemicals stored in the fatty tissue of humans and other organisms.

A 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.

Advantages of surface impoundments include

low construction costs, low operating costs, can be built quickly, wastes can often be retrieved if necessary and can store wastes indefinitely with secure double liners.

Waste management attempts to

manage wastes in ways that reduce their environmental harm without seriously trying to reduce the amount of waste produced. It typically involves mixing wastes together and then transferring them from one part of the environment to another, usually by burying them, burning them, or shipping them to another location.

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.

Advantages of deep-well disposal include

safe method if sites are chosen carefully, wastes can often be retrieved if problems develop, easy to do and low cost.

disadvantages of phytoremediation include

slow (can take several growing seasons), effective only at depth plant roots can reach, some toxic organic chemicals may evaporate from plant leaves and some plants can become toxic to animals.

sanitary landfills

solid wastes are spread out in thin layers, compacted, and covered daily with a fresh layer of clay or plastic foam, which helps to keep the material dry and reduces leakage of contaminated water.

plasma arc torch

somewhat similar to a welding torch, to incinerate them at very high temperatures. This process decomposes liquid or solid hazardous organic waste into ions and atoms that can be converted into simple molecules, cleaned up, and released as a gas.

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.

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. 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.

Disadvantages of deep-well disposal include

Leaks or spills at surface, leaks from corrosion of well casing, existing fractures or earthquakes can allow wastes to escape into groundwater and output approach that encourages waste production.

Disadvantages of burying waste in such landfills include:

Noise and traffic, dust, air pollution from toxic gases and trucks, releases greenhouse gases (methane and CO2) unless they are collected, slow decomposition of wastes, output approach that encourages waste production, eventually leaks and can contaminate groundwater.

There are two reasons for sharply reducing the amount of solid and hazardous wastes we produce

One reason is that at least three-fourths of these materials represent an unnecessary waste of the earth's resources -A second reason is that the production of the products we use and often discard creates huge amounts of air pollution, greenhouse gases, water pollution, land degradation, and ocean pollution.

Waste reduction based on three Rs:

Reduce: consume less and live a simpler lifestyle. Reuse: rely more on items that can be used repeatedly instead of on throwaway items, and buy necessary items secondhand or borrow or rent them. Recycle: separate and recycle paper, glass, cans, plastics, metal, and other items, and buy products made from recycled materials.

Three factors hinder reuse and recycling

The market prices of almost all products do not include the harmful environmental and health costs associated with producing, using, and discarding them. The economic playing field is uneven, because in most countries, resource-extracting industries receive more government tax breaks and subsidies than reuse and recycling industries. The demand, and thus the price paid, for recycled materials fluctuates, mostly because buying goods made with recycled materials is not a priority for most governments, businesses, and individuals.

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.

One method is waste reduction

This low-waste approach sees solid waste as a potential resource, which should be reused, recycled, or composted. -It discourages waste production in the first place. -It encourages waste reduction and prevention.

Hazardous waste

can be incinerated to break them down and convert them to less harmful chemicals.

Recycling

collects waste materials, turns them into useful products, and sells the new products. -it involves reprocessing discarded solid materials into new, useful products - secondary recycling involves converting materials into different products.

Disadvantages of incinerating solid include

expensive to build, costs more than short-distance hauling to landfills, difficult to site because of citizen opposition, some air pollution and CO2 emissions, older or poorly managed facilities can release large amounts of air pollution, output approach encourages waste production, and can compete with recycling for burnable materials such as newspaper.

Disadvantages of surface impoundments include

groundwater contamination from leaking liners ( or no lining), air pollution from volatile organic compounds, overflow from flooding, disruption and leakage from earthquakes and output approach that encourages waste production.

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.

resource exchange webs

in which the wastes of one manufacturer become the raw materials for another.

Composting

is a form of recycling that mimics nature's recycling of nutrients. It involves using decomposer bacteria to recycle yard trimmings, food scraps, and other biodegradable organic wastes. The resulting organic material can be added to soil to supply plant nutrients, slow soil erosion, retain water, and improve crop yields.

The Basel Convention

is an international treaty banning developed countries from shipping hazardous waste to other countries without their permission.

Waste reduction tries to

produce much less waste and pollution, and the wastes that are produced are considered to be potential resources that can be reused, recycled, or composted.

Advantages of recycling solid waste include

reduces air and water pollution, saves energy, reduces mineral demand, reduces greenhouse gas emissions, reduces solid waste production and disposal, helps protect biodiversity, can save landfill space, and serves as an important part of economy

Advantages of burying waste in such landfills include

reduces trash volume, less need for landfills, low water pollution, concentrates hazardous substances into ash for burial, sale of energy reduces cost, modern controls reduce air pollution, and some facilities recover and sell metals.

Advantages of incinerating solid include

reduces trash volume, less need for landfills, low water pollution, concentrates hazardous substances into ash for burial, sale of energy reduces cost, modern controls reduce air pollution, and some facilities recover and sell metals.


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