Solid and Hazardous Waste

Chapter 22

Solid waste

Most solid waste in the US is produced by industry75% mining13% agriculture9.5% industrial1% sludge

Only 1.5% of waste is household waste

That’s a lot of trash

Municipal solid waste – household waste averaged about 1500 pounds per person in the US

This is two to three times other developed countries

Hazardous Waste

The legal definition:

Contains one of 39 toxic, carcinogenic, mutagenic, or teratogenic compounds above EPA limits

Catches fire easily Reactive or unstable Capable of corroding metal containers

Hazardous Waste What is not defined as hazardous

RadioactiveHousehold toxic chemicalsMining waste with heavy metalsOil drilling wasteLiquid waste with organic hydrocarbon compoundsCement dustSmall business hazardous waste if under 100 kilograms

per month

Hazardous!!

It is estimated that of the 5.5 billion metric tons produced each year, only 6% is defined as hazardous and monitored correctly

94% is discarded by homes and industry not defined as hazardous and is therefore not regulated

Two options

Waste management – develop methods for storing and neutralizing waste

Pollution prevention – find ways to decrease amount of waste producedThis is the four “R’s”

Waste prevention Reduce Reuse Recycle

Rot (compost) Redesign

These are listed in order of increasing energy required

Slide 6

Fig. 21.6, p. 529

Aluminum can, used once

Steel can used once

Recycled steel can

Glass drink bottle used once

Recycled aluminum can

Recycled glass drink bottle

Refillable drink bottle, used 10 times

0 8 16 24 32

Energy (thousands of kilocalories)

Our new goal

Reduce waste pollution Reuse as much as possible Recycle/compost as much as possible Chemically treat/incinerate the rest Bury the remaining material in a sanitary landfill

Slide 7

Fig. 21.7, p. 530

Reduces globalwarming

Reduces aciddeposition

Reduces urbanair pollution

Make fuelsupplies

last longer

Reducesair pollution

Savesenergy

Reducesenergy demand

Reduceswater pollution

Recycling

Reduces solidwaste disposal

Reducesmineraldemand

Protectsspecies

Reduceshabitat

destruction

Producing less waste best choice

Save energy and virgin resources Reduce environmental impact of acquiring

material Improve worker health and safety Decrease pollution control/waste management

costs Less long term costs associated with cleanup

Ways to produce less waste Decrease consumption Redesign manufacturing to use less virgin material Redesign products to be less polluting Redesign manufacturing to be more efficient Use less hazardous products at home Design products to last longer (non-disposable) Reduce packaging Trash tax – pay by the pound

Slide 10

Fig. 21.10, p. 536

Power plant

Steam

Turbine GeneratorElectricity

Crane

Furnace

Boiler

Wetscrubber

Electrostaticprecipitator

Conveyor

Water Bottomash

Conven-tionallandfill

Wastetreatment

HazardousWastelandfill

Dirtywater

Waste pit

Smokestack

Flyash

Slide 11

Fig. 21.11, p. 536

Advantages

Reduced trashvolume

Less need forlandfills

Low waterpollution

Disadvantages

High cost

Air pollution(especiallytoxic dioxins)

Produces ahighly toxic ash

Encourageswaste production

Slide 12

Fig. 21.12, p. 537

Topsoil

Sand

Clay

Garbage

Garbage

Sand

Synthetic liner

Sand

Clay

Subsoil

When landfill is full,layers of soil and clayseal in trash

Methane storageand compressor

building

Electricitygeneratorbuilding

Leachatetreatment system

Methane gasrecovery

Pipe collect explosivemethane gas used as fuel

to generate electricity

Compactedsolid waste

Leachatestorage tanks

Leachatemonitoringwell

Leachatemonitoringwell

GroundwaterGroundwater

Groundwatermonitoringwell

Groundwatermonitoringwell

Leachate pipesLeachate pipes Leachate pumped upto storage tanks for

safe disposal

Leachate pumped upto storage tanks for

safe disposal

Clay and plastic liningto prevent leaks; pipescollect leachate from

bottom of landfill

Slide 13

Fig. 21.13, p. 538

Advantages

No open burning

Little odor

Low groundwaterpollution if sitedproperly

Can be builtquickly

Low operatingcosts

Can handle largeamounts of waste

Filled land canbe used for otherpurposes

No shortage oflandfill space inmany areas

Disadvantages

Noise and traffic

Dust

Air pollution fromtoxic gases andvolatile organiccompoundsreleasegreenhousegases (methaneand CO2)

Groundwatercontamination

Slowdecompositionof wastes

Encourages waste production

Eventually leaksand cancontaminategroundwater

Slide 14

Fig. 21.14, p. 538

Advantages

Safe method ifsites are chosencarefully

Wastes can beretrieved ifproblemsdevelop

Low cost

Disadvantages

Leaks or spills atsurface

Leaks fromcorrosion of wellcasing

Existing fracturesor earth quakescan allow wastesto escape intogroundwater

Encourageswaste production

Slide 15

Fig. 21.15, p. 539

Advantages Disadvantages

Inexpensive

Can store wastesindefinitely withsecure doubleliners

Groundwatercontaminationfrom leaking liners(or no lining)

Air pollution fromvolatile organiccompounds

Overflow fromflooding

Disruption andleakage fromearthquakes

Promotes wasteproduction

Slide 16

Fig. 21.16, p. 539

Bulk waste

Imperviousclay

Earth

Water table

Groundwater

Clay cap

Gas vent

TopsoilEarth

Sand

Plastic cover

Impervious clay cap

Leakdetectionsystem

Reactionwastesin dreams

Double leachatecollection system

Plastic double liner

Groundwatermonitoringwell

Slide 17

Fig. 21.17, p. 540

Wastetransporter

Hazardous waste

Supportcolumn

Inspector

Elevator shaft

Slide 18

Fig. 21.18, p. 542

Lead in airfrom industrial

incinerationand past auto

emissions

Lead insoil and in streets

Waterservice

main

Lead inpaint

Lead glazeon ceramics

Lead in waterfrom pipes,

fixtures, andservice lines

Toy andfloor dust

Lead in dust

Lead in food

Service line

Undergroundpumpor well

or