SOLID WASTE

Statistics

• Solid waste produced by one person – Each day…about 4.5-5 pounds– Each year… 1,825 pounds– In a 70 year lifespan…127,750 pounds

• 180 million metric tons of solid waste is disposed of per year in the U.S.

Solid Waste

•98.5% is from–1. Mining–2. Oil and gas production–3. Agriculture–4. Sewage treatment–5. Industry

•1.5% is municipal solid waste (MSW)

Waste Stream

• The steady flow of varied waste from domestic garbage and yard wastes to industrial, commercial and construction refuse.

• Municipal Solid Waste (MSW) is domestic waste & is composed of…

Composition of domestic waste in U.S.

Paper, 38%

Food, 7%

Glass, 7%Yard

Waste, 18%

Plastics, 8%

Metals, 8%

Misc., 14%

Most refuse is mixed…

• Makes separation an expensive process

• Mixes hazardous waste with normal waste, making disposal or burning dangerous

History of Garbage Disposal

• Hunters & gathers– ultimate composters– No packaging– All biodegradable

Open Dumps• 1st created in 500 B.C. in Athens,

Greece• Outlawed in U.S. & many other

MDC. Some illegal dumping still occurs

• Still in use by most developing countries.– Mexico city produces 10,000 tons

of trash each day.– Many poor families work these

dumps to get food or recyclables for $

• Garbage is simply dumped anywhere.

• Cons:– Attracts vermin & insects– Smells– Methane causes spontaneous fires

(Smokey Mtn in Phillipines)– Aesthetic degredation

Ocean Dumping

• 55 million lbs of bottles, cans, plastic are dumped at sea

• 330 million lbs of fishing gear- lines, nets, etc. lost each year

• New York did not stop dumping sewage until 1992!

Sanitary Landfills• #1 disposal method for majority of MSW in U.S.• Located on geologically stable areas- solid bedrock with impermeable soil

– Now try to avoid areas near rivers, lakes, floodplains & aquifer recharge zones• Dig a large pit• Layers of clay and/or plastic form base of landfill

– Prevents hazardous chemicals (oil, chemicals, metals, etc.) from leaching into soil

– Drainage pipes may be added to remove leachate • Trash is added, compacted, then covered with soil

– This deters vermin & reduces odor• Methane pipes & vents may be added to prevent methane build up that

might result in explosions• When landfill is full, final layers of dirt are added, trees & plants are planted

on mound.• Groundwater is monitored over time to check for leaking landfills

Sanitary Landfills

• Cons:– NIMBY: Not In My Back

Yard• Aesthetic degradation

– Rising land prices & shipping costs

– Running out of landfill space

• Many places having to pay large sums to ship garbage to other communities

– Demanding maintenance requirements/laws

– Becoming more expensive

Garbage Imperialism• Sending waste to LDC or poor

neighborhoods for disposal– Many communities try to sell waste to Indian

reservations b/c they are not under same fed. regulations

• Most MDC have agreed to stop shipping hazardous & toxic waste to LDC, but still occurs.

– EX: 1999, Bel Trang, Cambodia received 3000 tons of incinerated plastic waste. Happy residents used packaging from waste for rice storage, bedding, roofing. Ended up with mercury poisoning. Plastic company paid a $3 million bribe to Cambodian officials to dispose of their waste. Went back to pick it up, but damage already done.

• “Recycle” toxic material into something else.

– Ex: toxic waste recycled into asphalt or concrete filler for building highways; phosphogypsum from phosphate mining is sold as soil amendment (fertilizer) which does help plants grow but is radioacitve

Incineration• Garbage is burned• Also used as energy recovery

(waste to energy) when garbage burned to boil water, produce steam & create energy

• Pros:– Reduce landfill space– Only bury ash– Extends life of a landfill

• Cons:– Expensive– Air pollution– May be toxic ash residue- dioxin,

furans, lead, cadmium– If used to create energy must

have consistent stream of garbage so doesn’t work well in communities that recycle heavily.

Types of Incinerators

• Refuse-derived fuel– Unburnable or recyclables are removed before

burning– More time consuming & expensive– Creates less harmful emissions

• Mass burn– Dump everything smaller than a sofa into burn pit– Less expensive, easier– Causes more air pollution & maintenance on

chimneys

How can we shrink the waste stream so we don’t have to rely on disposal methods?

• REDUCE!

• REUSE!

• RECYCLE!

• In that order…

REDUCE

• Reduce the amt of waste you generate- preferred method of waste reduction

• Buy foods with less packaging• Bring your own bags for carrying

groceries- no paper OR plastic• Bring your own bottles/cups• Look for products that use fewer

toxins• If choosing between glass, metal or

plastic- choose glass or metal• Preferred Hierarchy:

– No packaging– Minimal packaging– Reusable packaging– Recyclable packaging

• Compost your yard waste & kitchen scraps

• If using plastic use photodegradable or biodegradable plastic– Cons:

• Don’t go away completely• May add toxins to soil• Never decompose in sanitary

landfill• People may think littering is

OK

REDUCE

• Since 1977, the weight of 2-liter plastic soft drink bottles has been reduced from 68 grams each to 51 grams

• That means that 250 million pounds of plastic per year has been kept out of the waste stream

REUSE• Reuse/resell things that are still

good• Auto parts sold thru junkyards-

demanufacturing• Salvage parts (doors, stained glass)

from old buildings• Some areas provide money to

return bottles for refilling• Donate clothing/toys to charities

that will sell them for money• Preferred over recycling because

material doesn’t have to be reprocessed

RECYCLE• Reprocessing of discarded materials into

new, useful products.• Recycle glass into other glass products• Recycle tires into rubberized road

surfacing• Problems:

– Plastic recyclables can be contaminated by one PVC bottle in a truckload

– Plastic recycling is down 50% b/c so many people consume these bottles on the go.

• Benefits:– Saves water, energy, raw materials, land

space– Lowers demand for raw resources- less

deforestation, mining• Producing aluminum from scrap instead of

bauxite ore cuts energy need by 95%– Reduces pollution– Makes one think about waste they produce– Cut waste volumes & reduce pressure on

landfills– Reduces litter problems

% composition of recycled materials in U.S.

Paper & paper board, 71%

steel, 12%

aluminum, 4%

plastic, 6%

glass, 7%

COMPOSTING• Breakdown of organic cmpds with

aerobic bacteria• Can be used as organic fertilizer• Can include anything except meat

or dairy• Benefits:

– Keeps organic wastes out of landfills

– Provides nutrients to the soil– Increases beneficial soil

organisms (e.g., worms and centipedes)

– Suppresses certain plant diseases– Reduces the need for fertilizers

and pesticides– Protects soils from erosion

Energy from Waste

• “Every year we throw away the energy equivalent of 80 million barrels of oil in organic waste in the U.S.”

• Trap methane from landfill to use like natural gas

• Burn garbage to create steam to create energy

• Organic material can be digested in digester with bacteria that produce methane which can be used like natural gas (farms may use this with animal manure)

HAZARDOUS & TOXIC WASTE

Hazardous waste

• Any discarded material, liquid or solid that contains substances known to be…– Fatal to humans or lab

animals in low doses– Toxic, carcinogenic,

mutagenic, or teratogenic to humans or other life-forms

– Ignitable with a flash point less than 60°C

– Corrosive– Explosive or highly reactive

• Biggest source of toxins are chemical & petroleum industries

Household Hazardous Waste

• Common household items such as paints, cleaners, oils, batteries, and pesticides contain hazardous components

• Labels – danger, warning, caution, toxic, corrosive, flammable, or poison identify products that might contain hazardous materials

• Leftover portions of these products are called household hazardous waste (HHW)

• These products, if mishandled, can be dangerous to your health and the environment

Proper Handling of HHW• The best way to handle HHW

is to reduce the amount initially generated by giving leftover products to someone else to use

• Many communities have set up collection programs to prevent HHW from being disposed of in MSW landfills and combustors

• These programs ensure the safe disposal of HHW in facilities designed to treat or dispose of hazardous waste

• More than 3,000 HHW collection programs exist in the United States

Resource Conservation and Recovery Act (RCRA)

(all about prevention)

•The Resource Conservation and Recovery Act (RCRA) was enacted by Congress in 1976 and amended in 1984. •Primary goal- to protect human health and the environment from the potential hazards of waste disposal. •In addition, RCRA calls for

– conservation of energy and natural resources– reduction in waste generated– environmentally sound waste management practices.

•Cradle to grave law- must keep record of hazardous waste from time created to time disposed of.

About Superfund

• Years ago, people were less aware of how dumping chemical wastes might affect public health and the environment

• On thousands of properties where such practices were intensive or continuous, the result was uncontrolled or abandoned hazardous waste sites, such as abandoned warehouses and landfills

About Superfund

• Citizen concern over the extent of this problem led Congress to establish the Superfund Program in 1980 to locate, investigate, and clean up the worst sites nationwide

• The EPA administers the Superfund program in cooperation with individual states and tribal governments

• The office that oversees management of the program is the Office of Emergency and Remedial Response (OERR)

Superfund Legislation (all about the clean up)

• Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA); 1980– “Superfund” to clean up abandoned sites– Hazard Ranking System (HRS)– National Priority List (NPL)

• Qualifications…– Leaking or have potential for leaking toxins– Site contains: lead, trichloroethylene, toluene, benzene, PCB’s, chloroform,

phenol, arsenic, cadmium, chromium

– Reauthorized in 1986 (SARA)• Toxic Release Inventory- requires 20,000 manufacturing facilities to report

annually on releases of more than 300 toxic materials.

• Intended as a solution to those previously contaminated sites with no one to pay for clean up

• Two levels– Emergency response

• immediate threat to human health or environment

– Long term remediation• if Hazard Ranking System (HRS) shows a

score over 27.5, it is added to the National Priorities List (NPL) for Superfund cleanup

• 1300 sites on NPL in 1990, more to come

Superfund sites in Georgia

• http://www.epa.gov/superfund/sites/npl/ga.htm#Diamond_Shamrock_Corp._Landfill

Examples of Hazardous Waste Sites

• Old industrial plants- smelters, mills, oil refineries (esp. around Great Lakes & Gulf Coast)

• Mining districts, railyards, abandoned filling stations

• Old dumps- indiscriminate dumping of many items– Love Canal in Niagara Falls,

NY- community built on old dump holding 20,000 tons of toxins

– Hardeman, TN- 250,000 barrels of chemical waste buried in shallow pits, leaked into water

Cleaning up Hazardous Waste Sites

• Brownfields- areas of land that are not being used to potential b/c do have or may have pollutants in soil or water.

• Columbia, Mississippi– 81 acres contaminated

w/turpentine & pine tar– Concentrations of phenols above

federal standards– Added to Superfund NPL site– Some experts recommended

covering w/soil & enclosing w/fence

– Instead, EPA made Reichhold Chemical (last owner of property) to pay $4 million to remove 12,500 tons of soil and replace with clean soil so may be used for homes

– Took contaminated soil to a hazardous waste dump in Louisiana

Hazardous Waste Management & Disposal

• Source reduction- don’t buy it or buy items that include toxic chemicals• Recycling reduces need for harmful chemicals• Waste exchange- one company gets rid of waste which is a raw material for

another; both win- generator doesn’t pay disposal cost, recipient pays little for raw material

• Convert to Less Hazardous Substance– Physical Treatment- charcoal or resin filters absorb toxins, metals & radioactive

substances can be fused with silica to make stable, impermeable glass– Incineration- heating over 1000C for a period of time leads to complete

destruction; ash is safer to store or uses less space– Chemical Processing- makes toxic material non-toxic; neutralization, oxidation,

removal of metals– Bioremediation- microorganisms absorb, accumulate & detoxify; activated sludge

basins, oil spills; better to keep in reaction vessels instead of releasing to env.• Stored Permanently

– Retrievable Storage- secure building, salt mine, bedrock cavern (Yucca Mtn) so can accessed, checked on, removed If necessary; more expensive, must be guarded & monitored

– Secure Landfills- similar to regular landfill but may be located on industry property