WASTECHAPTER 19

MS. NAPOLITANO & MRS. WARRENENVIRONMENTAL SCIENCE

PART I: SOLID WASTE

SOLID WASTE• Solid waste – any discarded solid material

• Includes junk mail, coffee grinds, cars, and other garbage

• ~10 billion metric tons of garbage each year in the US only

• Amount of solid waste doubled since 1960s

MUNICIPAL SOLID WASTE• Municipal solid

waste – waste produced by households & businesses• About 2% of US

solid waste

• ~210 million metric tons per year in US only

OTHER SOLID WASTE – MANUFACTURING, MINING, AGRICULTURE• 98% of US solid waste• Manufacturing = 56%

• Includes scrap metal, plastics, paper, sludge, & ash• Consumers indirectly create waste by purchasing from

manufacturers

• Mining waste leftover rock & minerals• Left in large heaps, dumped in oceans/rivers, or refilled into

abandoned mines

• Agricultural waste = 9%• Includes crop waste & manure• Most is biodegradable

WHERE DOES OUR TRASH GO?

LANDFILLS• Landfill – permanent waste-disposal facility

• Wastes are put in the ground & covered by soil, plastic, or both

• Contains buried waste• >50% of municipal & manufacturing waste

ends up in landfills• Requires caution: waste in a landfill cannot

come in contact with the surrounding soil or groundwater

PROBLEMS WITH LANDFILLS• Leachate – liquid that has passed through

solid waste in a landfill• May contain chemicals from paints, pesticides,

cleansers, cans, batteries, & appliances• May flow into nearby groundwater if not monitored

• Decomposing organic waste with no oxygen produces methane gas• Highly flammable• May be pumped out of landfills & used as fuel

SAFEGUARDING LANDFILLS• The Resource Conservation and Recovery

Act (1976, updated 1984)• New landfills must be built with safeguards to

reduce pollution• Lined with clay & plastic for collecting leachate• Vents carry methane out of landfill• Expensive!

BUILDING MORE LANDFILLS

INCINERATORS• Incinerators reduce solid weight

• Ash still has to be disposed of in landfills

• Materials that should/should not be burned are not separated• Cleansers, batteries, & paints should not be

burned but wind up in the atmosphere• Makes polluting gas

PART II: REDUCING SOLID WASTE

SOURCE REDUCTION• Source reduction – any change in design,

manufacture, purchase, or use of materials/products to reduce the amount of toxicity before becoming solid waste• Includes reuse of products/materials

HOW TO REDUCE SOLID WASTE• Consumers influence manufacturers

• Buy products that have less packaging or that last longer

• Ex: dish towels vs. paper towels

• Manufacturers could redesign products to use less materials

RECYCLING• Recycling – process of reusing or

recovering materials from waste or scrap

• Saves energy, water, & other resources

• Ex: 95% less energy needed to produce aluminum from recycled aluminum than from ore

https://www.youtube.com/watch?v=AOpGhAdQFEY

COMPOSTING• Compost –

decomposed plant & animal matter • Spread onto gardens

to enrich soil• Includes manure &

rotting plants

CHANGING USED MATERIALS• Be smart about purchases!

• Buy large-serving containers instead of individual-serving containers

• Recycle a combination of common household products• Ex: newspapers, magazines

• Some products can be recycled into other products• Ex: aluminum cans can make lawn chairs

DEGRADABLE PLASTICS• Photodegradable plastics – become weak

& brittle in the sun

• Green plastic – made from sugars (living)

• Problems:• Small pieces do not disappear completely• Pieces can spread around

PART III: HAZARDOUS WASTE

HAZARDOUS WASTE• Hazardous waste – any waste that is a risk to the

health of living things• May be solids, liquids, or gases• Often contain toxic, corrosive, or explosive materials• Examples:

• Dyes, cleaners, solvents• Pesticides• Radioactive wastes• Toxic heavy metals (lead, mercury, etc.)• PCBs (polychlorinated biphenyls)

THE RESOURCE CONSERVATION AND RECOVERY ACT (RCRA)

• Requires producers of hazardous waste to keep records of how wastes are handled

• Regulates hazardous waste treatment & disposal facilities

LOVE CANAL (NIAGARA FALLS)• Homes & schools were built on land that

was once a toxic waste dump site• Toxic chemicals found in sump pumps• Resulted in birth defects & miscarriages• Federal government relocated & reimbursed

over 800 families• Influenced passage of the Superfund Act

THE SUPERFUND ACT• AKA The Comprehensive Environmental

Response, Compensation, & Liability Act

• Gave the EPA the right to sue owners of hazardous waste sites who illegally dumped wastes

• EPA can also force owners to pay for cleanup

NUMBER OF SUPERFUND SITES

PREVENTING HAZARDOUS WASTE• Produce less (duh)

• Manufacturers can redesign methods to produce less/no hazardous waste

• Saves money by cutting costs of materials & waste disposal

• Find ways to reuse it• Programs can be set up between companies that can reuse

waste in other ways

• Some types of wastes can be treated with chemicals to make the wastes less hazardous• Ex: lime (base) can be mixed with acids to make neutrals

LAND DISPOSAL• Concentrated/solid wastes are put in barrels &

buried in landfills• Deep-well injections – wastes are pumped deep

into the ground• Covered with cement to prevent groundwater

contamination• Surface Impoundment – pond with a sealed

bottom• Waste settles to the bottom, water evaporates & leaves

room for more

LAND DISPOSAL (CONT’D)• Some wastes can be broken down with biological

& chemical agents• Broken down by bacteria, flowering plants, trees• Dispersants used in oil spills to break down oil

• May be incinerated• Expensive – requires a lot of energy• Must be monitored carefully• Ash still needs to be buried – hazmat landfills

• Before 1980, companies sent wastes to less-populated states or other countries

DISPOSING OF HAZARDOUS WASTE AT HOME• Some household products

should not be disposed of in general solid-waste landfills

• Many cities provide collections for household hazardous waste

MOTOR OIL• It is illegal to pour motor oil on the ground

or throw it in the trash• People in US throw away ~185 million gallons of

used motor oil each year• Instead, you should:

• Take it to a service station for recycling• Bring it to oil-collection receptacles (some cities

only)• Contact your local city government!