00:00:01 Municipal solid waste.

00:00:06 Trash.

00:00:09 Refuse.

00:00:12 No matter what you call it, it all means the same thing.

00:00:17 Garbage.

00:00:20 Tons of garbage.

00:00:24 Mountains of garbage.

00:00:25 Garbage is a topic that will not go away anytime soon.

00:00:32 As long as we make it, we will need to manage it.

00:00:36 And to do that, it is important to have a better understanding of what garbage is and how it is generated.

00:00:43 For as long as humans have inhabited the earth, we have made garbage.

00:00:59 We left bones, the remains of fires, human waste, other scraps, and then we moved on.

00:01:07 As hunters and gatherers, our numbers were small, and nature easily recycled everything we didn't use.

00:01:15 When we learned to grow food, we stayed in one place, and our problems with garbage began.

00:01:24 Villages grew, and methods of getting rid of it had to be found.

00:01:29 Archaeologists discovered that some prehistoric tribes in North America filled acres of land with clam and oyster shells collected from their feasts.

00:01:40 In fact, one enormous collection in what is now Maryland encompassed 30 acres, equal to 23 football fields, and was 10 feet deep, or as high as a basketball hoop.

00:01:53 In ancient Troy, most household garbage was simply dropped on the dirt floor.

00:01:59 When animal bones, vegetable peelings, and other debris made it too messy, it would be covered with a new layer of clay and soil.

00:02:08 As towns grew into cities, the need to deal with waste in more effective ways became essential.

00:02:15 Today, there's so much garbage that managing it has become an environmental science.

00:02:21 In 1998, the United States alone generated more than 220 million tons of municipal solid waste.

00:02:30 That's enough to fill the New Orleans Superdome almost 80 times.

00:02:34 That's the waste you and I create every day.

00:02:38 In fact, that's about four and a half pounds for each and every one of us, and that's quite a bit.

00:02:47 Included in municipal solid waste are packaging materials, some as small as a gum wrapper.

00:02:53 Also found are everyday items such as food scraps, furniture, clothing, bottles, newspapers, appliances, and other items we use every day.

00:03:08 Also found are everyday items such as food scraps, furniture, clothing, bottles, newspapers, appliances, and other items we use and then discard.

00:03:26 We live in a society where products are designed to be used once or twice and then thrown away.

00:03:33 Many of these items are packaged in attractive little containers with separate cartons holding individualized servings.

00:03:43 While this helps us to use only what we need, it also creates a great deal of waste that can cause pollution of the land, air, and water if not handled properly.

00:03:59 So where does it all come from?

00:04:01 Of the 220 million tons of waste we generate every year, 33%, 72 million tons is from containers and packaging from manufactured products like games, toys, and household items.

00:04:19 Another 13%, or 28 million tons, is from grass clippings and yard trimmings.

00:04:26 An additional 16%, or 35 million tons of waste, is composed of non-durable goods, items that don't last very long, such as old clothing, paperboard products, and other materials.

00:04:46 We call these different sources of garbage, and where they ultimately end up, the waste stream.

00:04:53 The term waste stream means the flow of residential and commercial garbage that can either be recycled, reused, or disposed of by being sent to a landfill or other disposal facilities.

00:05:10 As this animation demonstrates, the stream of waste forks to recycling facilities, which reduces the quantity and then continues downstream.

00:05:22 Eventually, portions of it will be directed to landfills, to waste-to-energy facilities, and in the future, to processing centers currently being developed by scientists.

00:05:37 But we're not finished with the numbers yet. Remember that 220 million tons of garbage a year?

00:05:44 Another way of looking at the waste stream is to realize that there are some things that last a long time, called durable goods, and other things that decompose or break down quickly.

00:05:57 Durable goods make up 27% of the total, or 60 million tons, and include metal, glass, and plastics, from items such as stereos, TVs, and household appliances, as well as rubber, leather, wood, and various textiles.

00:06:18 The rest of those 220 million tons of garbage is made up of food and other miscellaneous organic and inorganic wastes.

00:06:32 Before garbage can be recycled, treated, or disposed of, it has to be collected, and the way it is collected has a lot to do with what happens to it next.

00:06:42 What used to be a process handled by men with horse-drawn carts, later evolved into fleets of trucks, specially designed for handling and compacting garbage.

00:06:57 In the 1940s and 50s, a container called a dumpster was developed and made the collection process much easier.

00:07:07 Today, we have specialized recycling collection equipment and nationwide programs for the residential collection of plastic, glass, metal, and paper.

00:07:21 The garbage collection vehicles we see in our neighborhoods are engineered to make the process safer and more efficient.

00:07:30 But keep in mind that how we set our garbage out at home affects how it's handled and where it ends up.

00:07:40 If recyclables are put into a recycling bin, they will not go to the same place as they would have placed in a garbage container.

00:07:49 In 1998, 63 million tons of new recyclables was collected.

00:07:55 That's enough to fill the Empire State Building 73 times.

00:08:02 That's pretty good, but I think you'll agree we can do more.

00:08:07 We'll discuss that in a moment, but first, even with all of our waste reduction and recycling efforts, the amount of waste we make has grown from 88 million tons per year in 1960 to more than 220 million tons per year today.

00:08:22 An increase caused, for the most part, by the growth in population and the increase of consumer goods.

00:08:31 Although many solutions exist to deal with solid waste, each has different benefits and concerns.

00:08:38 At present, about 125 million tons, or 55 percent of the municipal solid waste generated, goes into landfills.

00:08:46 Often the most efficient and secure way to get rid of garbage.

00:08:53 Landfills as we know them have been used for more than 30 years and dot the landscape from coast to coast.

00:09:00 For those who've never seen one before, a landfill, such as the one shown here, is a carefully engineered facility into which garbage is placed and covered and is cyclically disposed of.

00:09:13 Into which garbage is placed and covered and is scientifically designed to protect the environment.

00:09:21 Landfill sites are chosen with great care.

00:09:25 The land on which they are placed must meet strict standards so that the ecosystem and water sources are protected.

00:09:33 A landfill is specifically designed to make certain that a substance called leachate, sort of like garbage juice, does not leak into the ground.

00:09:44 Leachate is the liquid that forms when rainwater mixes with the buried and decomposing garbage.

00:09:51 Keeping leachate in is accomplished by lining the bottom and sides of the landfill with a thick plastic liner placed over varying depths of compacted clay.

00:10:04 Clay is used because it is non-porous, meaning it doesn't allow liquids to get through.

00:10:11 The waste is then placed in the landfill, compacted and covered daily with several inches of soil.

00:10:20 This reduces odor, controls litter, insects and rodents and protects public health.

00:10:28 The number of open landfills in the United States has decreased from about 8,000 in 1988 to approximately 2,300 in 1998.

00:10:39 This is due in part to government regulations that require landfills to be designed to better protect the environment and because today they are larger and more expensive to operate.

00:10:55 So although the actual numbers of landfills have decreased, the amount of garbage that goes into them and the amount each will hold has increased.

00:11:05 Although there are many success stories regarding landfill technology, ongoing scientific research still needs to be conducted to ensure the continuing protection of the environment as well as the health and safety of surrounding communities.

00:11:23 Now let's talk about another method of dealing with garbage.

00:11:27 The process known as waste-to-energy actually burns the garbage, which results in the generation or creation of electric power.

00:11:37 According to the Integrated Waste Services Association, in 1999, waste-to-energy facilities in the U.S. combusted approximately 15% of the nation's solid waste.

00:11:51 That's about 33 million tons or enough to fill an 18-wheeler 380,000 times.

00:11:59 Facilities similar to this one in Fort Lauderdale, Florida, have been disposing of garbage and generating electricity since the first one was built over 25 years ago.

00:12:12 Every year, the 102 waste-to-energy facilities in the United States generate 2,800 megawatts of electricity.

00:12:21 These facilities serve the trash disposal needs of more than 37 million people and generate enough electricity to power 2.5 million homes.

00:12:36 But what happens when the waste is burned?

00:12:38 To start, the garbage is burned at temperatures exceeding 2,000 degrees Fahrenheit or 240 degrees Celsius.

00:12:46 At those temperatures, the organic materials in the trash are completely burned.

00:12:52 And what is left is ash or noncombustible material like scrap metal and dirt.

00:12:58 The hot gases produced in turn heat tubes in the walls of the trash disposal.

00:13:03 The steam is then used to turn a turbine generator that produces electricity.

00:13:12 The burning of the waste also results in gases and smoke that rise to the top of the furnace.

00:13:20 Modern waste-to-energy plants use high-temperature gas to generate electricity.

00:13:25 Gas and smoke that rise to the top of the furnace.

00:13:31 Modern waste-to-energy plants use high-efficiency scrubbers and dust collectors to clean the gases before they are released.

00:13:41 In the scrubbers, a mixture of lime and water is sprayed into the hot gas stream to cool the gases and remove acids such as hydrogen chloride and sulfur dioxide.

00:13:53 Finally, a fabric filter called a bag house acts like a giant vacuum cleaner and removes dust and heavy metals such as mercury before they finally go up and out the chimney.

00:14:07 The gases are so clean at this point that the only thing you see exiting the chimney is water vapor.

00:14:14 As for the ash, scrap metal and dirt that is left over after the process, they ultimately make their way to landfills for safe disposal.

00:14:29 And since we're back at the landfill, let's talk about a similar technology that burns landfill gases to make electricity.

00:14:37 The gas is produced when organic waste in a landfill decays.

00:14:43 These gases are approximately 50% methane, which is the same as the natural gas found throughout the world and can be collected for energy.

00:14:53 The remainder of landfill gas is mostly carbon dioxide with varying amounts of nitrogen and oxygen.

00:15:02 As with all sectors of the solid waste industry, special care is taken to ensure that the gases are properly managed.

00:15:10 Unlike municipal solid waste which goes into landfills or can safely be treated in waste-to-energy programs like the one in Fort Lauderdale, hazardous waste such as some chemicals and paints pose a threat to people and the environment and must be handled even more carefully.

00:15:32 One way to manage such waste is bioremediation.

00:15:37 Using microorganisms such as yeast, fungi or bacteria to break down hazardous waste into less harmful substances.

00:15:48 These tiny creatures eat organic materials like fuels or solvents and turn them into harmless products like carbon dioxide and water.

00:15:58 After the food source is gone, the organisms die off and become part of the waste product.

00:16:06 Bioremediation is a cost-effective natural process and has proven successful in many areas around the country.

00:16:15 As we've seen, waste is a serious subject with many possible solutions.

00:16:21 Though the three R's, reducing, reusing and recycling, have made a big dent in the volume of waste needing to be disposed of, the tonnage continues to increase as the population grows.

00:16:36 While we can reduce it at the source, home, office, school, reuse it or recycle it, it is still difficult to reduce, reuse or recycle it all.

00:16:50 So for the foreseeable future, we will need safe methods of disposal.

00:16:55 Yes, the statistics show that we are recycling a greater portion of our discards than ever before.

00:17:02 But we are still burying and burning a great deal as well.

00:17:06 We all need to do more.

00:17:09 According to the Environmental Protection Agency, also known as the EPA, at least one area has been changed through the practice of reducing waste at the source.

00:17:20 Disposal of yard trimmings has been reduced significantly through the composting of leaves and tree trimmings and by simply leaving grass clippings on the lawn after the yard is cut.

00:17:32 Composting is the transformation of organic material, like plants and food waste, into a soil-like material called compost or loam that looks, feels and smells just like dirt.

00:17:45 When added to gardens, compost enhances the quality of the soil.

00:17:53 Composting is far from new and can be traced back to Marco Cato, a farmer and scientist who lived in Rome 2,000 years ago.

00:18:02 He felt using compost was essential for maintaining healthy and productive land. And he was right.

00:18:10 Today, there are several reasons why composting remains an important practice.

00:18:16 Yard and food waste make up 27 percent, almost 60 million tons of the solid waste created in the United States, or enough to fill a two-lane highway from Houston to Dallas to a height of 100 feet.

00:18:30 Composting as much of this type of waste as possible will reduce landfill use by almost one-fourth.

00:18:40 In addition, it provides a byproduct that is useful for gardening, landscaping, agriculture and public works projects, such as beautifying parks, city streets and highways.

00:18:53 The home composting process is actually quite simple. You just put organic material in a pile and let it decompose or break down into smaller matter.

00:19:09 One composting process that's easy to set up at home or in school uses worms.

00:19:16 The worms eat the food scraps, which then become compost after being digested and passed through its body.

00:19:23 So all you need to get started is some plant and food waste, a secure container and some hungry worms.

00:19:31 And yes, the worms will even eat cafeteria food.

00:19:36 As you watch this video, you're probably wondering what you can do to help.

00:19:42 For starters, at home you can use cloth rags instead of paper towels.

00:19:48 Or you can reuse water and soda bottles, after a good cleansing of course.

00:19:54 And things that can't be reused, but can be recycled, should be placed in the proper bins.

00:20:01 You can also ask your parents to purchase canvas grocery bags that can be used over and over.

00:20:09 There is a lot that can be done using a little thought, imagination and the internet.

00:20:16 There are many websites, including ForMyWorld.com and Keep America Beautiful, which is located at kav.org.

00:20:25 These organizations, and many others like them, can provide innovative ideas for starting recycling programs in your community.

00:20:34 And in the case of ForMyWorld, the site even lists community programs by zip code so you can find one near you.

00:20:42 So the next time you're online, do a search at google.com with the word recycling and you'll be amazed at what comes up.

00:20:51 Your whole family can help too, by purchasing products that are packaged with recycled materials.

00:20:57 Or from companies who make an effort to reduce the amount of packaging they use.

00:21:04 There are other ways to help out at home, such as reusing the Sunday comics as wrapping paper.

00:21:10 Cutting down milk jugs and using them as scoops for your coffee.

00:21:14 Or by cutting a hole in the side and using the jugs to store plastic bags.

00:21:20 The point is to be creative and find new uses for things you'd normally throw away.

00:21:26 Just use your imagination.

00:21:32 By recycling, we preserve natural resources and save money.

00:21:38 By recycling, we preserve natural resources and save the energy we would normally use to manufacture things from raw materials.

00:21:48 We also generate less pollution and save ourselves millions of dollars in disposal costs by cutting down on the amount of garbage we throw out every day.

00:21:59 Waste is expensive.

00:22:02 It's expensive to collect.

00:22:04 It's expensive to collect, to transport, and to treat.

00:22:10 Landfills and waste-to-energy facilities are effective and safe, but they are only a part of the solution.

00:22:19 We have evolved into a large and complex society that uses materials and resources in great quantities.

00:22:27 This results in vast amounts of waste that needs to be dealt with in a responsible way.

00:22:35 Since we can no longer just pile it up and move on, we must continue our scientific research to create methods of disposal and recycling that are safe for everyone.

00:22:47 Especially the environment, which we need to safeguard for future generations.

00:22:53 Managing waste has become an important issue.

00:22:57 We each need to look at the impact we're having on the environment and how we can use our natural resources more efficiently while reducing the amount of waste each and every one of us creates on a daily basis.

00:23:10 If everyone does their part, we can help ensure a safer, cleaner, and healthier planet for us all.

00:23:23 NASA Jet Propulsion Laboratory, California Institute of Technology