Chapter 4Chapter 4Land and Soil ResourcesLand and Soil Resources

Section 2Section 2

Solid WasteSolid Waste

Notes 4-2Notes 4-2

Trash FactsTrash FactsEach day, one American produces 10 kg Each day, one American produces 10 kg of trash.of trash.

Every hour, people throw away 2.5 million Every hour, people throw away 2.5 million plastic bottles.plastic bottles.

Every two week, there is enough glass Every two week, there is enough glass bottles and jars thrown away to fill the bottles and jars thrown away to fill the Twin Towers.Twin Towers.

Every year, people throw away 1.6 billion Every year, people throw away 1.6 billion pens, 2.9 million tons of paper towels and pens, 2.9 million tons of paper towels and 220 million tires.220 million tires.

Problem of Waste DisposalProblem of Waste Disposal

Solid Waste:Solid Waste: Things that people throw awayThings that people throw away Some can be liquidSome can be liquid Most is produced by agriculture, mining and Most is produced by agriculture, mining and

industryindustry

Municipal Waste:Municipal Waste: Produced by homes, business and institutionsProduced by homes, business and institutions

Can be buried, burned or maybe recycledCan be buried, burned or maybe recycled

Problem of Waste DisposalProblem of Waste Disposal

Landfills:Landfills: Old land fills were just holes in the groundOld land fills were just holes in the ground

Not safe and unsightlyNot safe and unsightly Sanitary LandfillsSanitary Landfills::

Constructed to hold wastes more safelyConstructed to hold wastes more safelyHolds solid waste, construction debris, agricultural Holds solid waste, construction debris, agricultural and industrial wastesand industrial wastesCovered with clay and soil, then grass and treesCovered with clay and soil, then grass and treesKeeps Keeps leachateleachate from forming from forming

Polluted water that filters through the waste and gets into Polluted water that filters through the waste and gets into drinking waterdrinking water

Problem of Waste DisposalProblem of Waste Disposal

Parts of a Landfill:Parts of a Landfill: Leachate collectionLeachate collection: polluted water collects at : polluted water collects at

the bottomthe bottom LinersLiners: thick layers of clay and plastic cover : thick layers of clay and plastic cover

the bottom and sides; keeps liquid from the bottom and sides; keeps liquid from leaking into the soilleaking into the soil

Solid waste LayersSolid waste Layers: compacted waste : compacted waste reduces volume; covered with soil or plasticreduces volume; covered with soil or plastic

Problems of Waste DisposalProblems of Waste DisposalParts of a Landfill (cont)Parts of a Landfill (cont) Gas recoveryGas recovery: bacteria break down wastes : bacteria break down wastes

and produce methane and carbon dioxide; and produce methane and carbon dioxide; gases can build up and cause explosions. gases can build up and cause explosions. Vent pipes collect the gases and release themVent pipes collect the gases and release them

Leachate treatmentLeachate treatment: leachate is pumped into : leachate is pumped into holding ponds and treated; then shipped to holding ponds and treated; then shipped to safe disposal sitessafe disposal sites

Monitoring wellsMonitoring wells: water wells are tested to : water wells are tested to make sure leachate is not escaping out of the make sure leachate is not escaping out of the landfilllandfill

Problems of Waste DisposalProblems of Waste Disposal

Incineration:Incineration: Burning of solid wastesBurning of solid wastes ProsPros

Incinerators take up less space than landfillsIncinerators take up less space than landfills

Don’t pose a risk of polluting the waterDon’t pose a risk of polluting the water

Heat can be used to produce electricityHeat can be used to produce electricity ConsCons

Can release some pollutants into the airCan release some pollutants into the air

Some wastes are left overSome wastes are left over

More expensive to build than landfillsMore expensive to build than landfills

RecyclingRecycling

Process of reclaiming raw materials and Process of reclaiming raw materials and reusing themreusing them Reduces the volume of solid wasteReduces the volume of solid waste Matter is naturally recycled in natureMatter is naturally recycled in nature

Biodegradable: broken down and recycled by Biodegradable: broken down and recycled by bacteria and other decomposersbacteria and other decomposers

Four major categories of wastes can be Four major categories of wastes can be recycledrecycled

Metal, glass, paper and plasticMetal, glass, paper and plastic

RecyclingRecycling

Metal:Metal: Metals can be melted and reusedMetals can be melted and reused Saves money and causes less pollution Saves money and causes less pollution

No ore needs to be mined, transported to factories No ore needs to be mined, transported to factories and then processesand then processes

Conserves nonrenewable resourcesConserves nonrenewable resources

RecyclingRecycling

Glass:Glass: Made from sand, soda ash and limestone Made from sand, soda ash and limestone

mixed and then heatedmixed and then heated One of the easiest products to recycleOne of the easiest products to recycle

Can be broken down and reheatedCan be broken down and reheated Less expensive to recycle than make newLess expensive to recycle than make new

Old pieces melt at lower temps and uses less Old pieces melt at lower temps and uses less energyenergy

Less environmental damage caused by mining Less environmental damage caused by mining new materialsnew materials

RecyclingRecyclingPaper:Paper: Takes 17 trees to make one metric ton of Takes 17 trees to make one metric ton of

paperpaper Turn wood into pulp: thick, liquid Turn wood into pulp: thick, liquid Pulp is spread and dried to make paperPulp is spread and dried to make paper Can use old paper (recycle)Can use old paper (recycle)

Washed first then mixed with water and chemicals Washed first then mixed with water and chemicals to form pulpto form pulp

Paper can only be recycled so many timesPaper can only be recycled so many timesEach time the paper becomes weaker, rougher Each time the paper becomes weaker, rougher and darkerand darker

RecyclingRecycling

Plastic:Plastic: Resin: solid left over when oil is refined to Resin: solid left over when oil is refined to

make gasoline and other petroleum productsmake gasoline and other petroleum productsHeated, stretched and molded to make plastic Heated, stretched and molded to make plastic productsproducts

Number on bottom of plastic container tells Number on bottom of plastic container tells what the plastic is made ofwhat the plastic is made of

Numbers 1 & 2 are often recycledNumbers 1 & 2 are often recycledMake milk jugs, detergent containers and soda Make milk jugs, detergent containers and soda bottlesbottles

RecyclingRecycling

Should we recycle?Should we recycle? Conserves resources and saves energyConserves resources and saves energy

Can save 90-97% energy by recycling aluminumCan save 90-97% energy by recycling aluminum 4-32% energy by recycling glass4-32% energy by recycling glass 23-74% energy by recycling paper23-74% energy by recycling paper

Not all materials can be recycled Not all materials can be recycled Some can’t be recycled (we don’t know how to)Some can’t be recycled (we don’t know how to)

Some we don’t have a need for after they are Some we don’t have a need for after they are recycledrecycled

Does produce some pollution and uses Does produce some pollution and uses energyenergy

RecyclingRecycling

Recycling Facts:Recycling Facts: http://www.recycling-revolution.com/recycling-

facts.html http://recyclingfacts.org/ http://www.environment-green.com/

Solid Waste ManagementSolid Waste Management

Most municipal wastes still go to landfillsMost municipal wastes still go to landfills

Recycling is becoming more popularRecycling is becoming more popular When materials are brought back, the people When materials are brought back, the people

are paid a deposit fee.are paid a deposit fee. Encourages people to recycleEncourages people to recycle Supermarkets recycle their bags and often Supermarkets recycle their bags and often

have bins for other materials as wellhave bins for other materials as well Get money for recycling metalsGet money for recycling metals

““Three R’s”Three R’s”

Reduce:Reduce: Creating less waste Creating less waste

Reuse:Reuse: Finding another use for the object instead of Finding another use for the object instead of

throwing it outthrowing it out

Recycle:Recycle: Reclaiming raw materials to create new Reclaiming raw materials to create new

productsproducts

CompostingComposting

Process of helping the natural Process of helping the natural decomposition process break down many decomposition process break down many forms of wasteforms of waste Yard trashYard trash

Leaves, grass clippingsLeaves, grass clippings Food wasteFood waste

Fruit, coffee grounds, egg shells, vegetablesFruit, coffee grounds, egg shells, vegetables Paper (shredded)Paper (shredded)

Excellent natural fertilizer for plantsExcellent natural fertilizer for plants