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WASTE

THE WASTE PROBLEM

More than 30 million tons of waste are generated worldwide yearly 2 % of it is exported

Contaminated waste sites are a problem Short term profit interests, lack of regulation and weak law enforcement

promote problems ongoing Issues of environmental justice are key

Health hazards Infectious disease risks from poorly managed solid waste Contamination of drinking water and soil by biological, chemical, and

mining wastes Gas migration and leachate discharges from landfills Emissions of air pollutants from incinerators Contamination of food by waste chemicals that escape into the

environment

WHAT IS WASTE?Waste Stream: everything we throw away.

Typically divided into three broad categories:Municipal solid waste

Special waste

Hazardous waste

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SPECIAL WASTES

Medical waste Generated from health care treatment or research facilities

(human and nonhuman) Have come into contact with body fluids or other materials

that may contain infectious agents and may cause disease Mining waste

The extraction of metals, coal, and oil from the Earth’s crust The volume of wastes from mining operations exceeds the

volume of wastes from all other categories combined Regulated both by solid waste laws and regulations and by

water pollution control and land use and reuse laws and regulations

Sewage sludge

E-WASTE

Disassembly and recycling of obsolete appliances and electronics The preferred strategies are to reuse the

equipment, recycle the materials, properly dispose of the equipment in an approved landfill

Heavy metals such as mercury, lead, and cadmium cause dangerous exposure as the electronics are processed unprotected70% of heavy metal contamination (lead,

cadmium, mercury) comes from e-wasteMuch being shipped to developing world-

environmental justice issue In Europe, manufacturers have “cradle to grave”

responsibility for their products

A CHINESE WOMAN EXTRACTS VALUABLE METALS FROM E-WASTE

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WASTE MANAGEMENT STRATEGIES

LANDFILLS

Most common waste method for disposal worldwide Historically, landfills have been a convenient, inexpensive

waste-disposal option. Rising land prices and shipping fees, and demanding

construction and maintenance requirements, are increasing costs.Suitable landfill sites are become scarce

1,200 - 1,500 landfills have closedCommunities are rejecting new landfills.

Positive trend in landfills is methane recovery

WASTE DISPOSAL METHODS

Sanitary Landfills Site selection is complicated

Cost of the land, insurance of an adequate area to provide waste disposal capacity for a reasonable time period, an adequate elevation or separation to protect regional ground water, available or appropriate soil for daily soil cover requirements, and an adequate buffer from surrounding populations

Refuse compacted and covered every day with a layer of dirtDirt takes up as much as 20% of landfill spaceMany now becoming “sanitary”

.

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INCINERATION

Reduces disposal volume by 80-90% Energy Recovery - heat derived from incinerated refuse is a

useful resource• Over 1000 waste to energy plants worldwide

Problems- Expensive Residual ash usually contains toxic material (dioxins, lead, cadmium)

Types of incinerators: Refuse-Derived Fuel Mass Burn Small scale incineration- Burn in backyard barrels, open dumps, and crude incinerators

DEEP WELL INJECTION AND OPEN DUMPING

Deep well injection: A liquid waste disposal technology

Open dumping Releases hazardous material Still the predominant method of waste disposal in

developing countries Most developed countries forbid open dumping.

Estimated 200 million liters of motor oil are poured into the sewers or soak into the ground each year in the U.S.

OCEAN DUMPING

Every year 20 million tons of plastic debris are dumped at sea

Significant impact on wildlife

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SHRINKING THE WASTE STREAM- PRIMARY MANAGEMENT

RECYCLING

Reprocessing of discarded materials into new, useful productsDeveloped world-

Aluminum cans, copperDeveloping world

Old tires for road surface, newspapers for insulationMunicipal level

Compost yard waste Construction waste can be recycledGasifiers convert biomass (food-soaked paper) to

natural gas

RECYCLING Benefits of recycling

Saves money, raw materials, and landfill spaceCosts $35/ton as opposed to $80/ton to landfill

Encourages individual responsibilityReduces pressure on disposal systems Lowers demand for raw resourcesReduces energy consumption and air pollution

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REUSE AND PRODUCE LESS

Reuse Auto parts, brass fittings, woodwork, bricks, are routinely

reused Glass and plastic bottles are washed and refilled Scavenging, sorting and reprocessing scraps from dumps

Produce less Individual responsibility Reduce excess packaging Paper, plastic, glass, and metal packaging material make up

50% of domestic trash

HAZARDOUS WASTE

HAZARDOUS WASTE

Legally, hazardous waste is any discarded liquid or solid that contains substances known to be: Fatal to humans or laboratory animals in low doses Toxic, carcinogenic, mutagenic, or teratogenic to humans or

other life-forms Ignitable with a flash point less than 60o C Corrosive Explosive or highly reactive

U.S. industries alone generate 265 million metric tons of officially classified hazardous wastes annually At least 40 million metric tons of toxic and hazardous

wastes are released into the environment

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HAZARDOUS WASTE MANAGEMENT OPTIONS

Produce Less Waste

Convert to Less Hazardous Substances Physical treatment, incineration, chemical processing,

bioremediation

Store Permanently Retrievable Storage

Can be inspected and periodically retrieved if necessary Secure Landfills

Multiple liners, covered by a cap,leachate is processed and monitored

TRANSPORT OF TOXIC WASTE

Transportation of hazardous wastes to disposal sites is dangerous

RADIOACTIVE WASTE

Contains radioactive chemical elements

Two subcategories Low-level waste: used protective clothing and other items

that contain low levels of radioactivity per mass or volume High-level : spent nuclear fuel and waste materials left

after spent fuel is reprocessed

Decommissioning of old nuclear plants 60 % of Americans support nuclear energy many plants

are oldWill cost 200 billion to 1 trillion dollars for all in US

Storage is a big problem

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WASTE REGULATION

REGULATION

UN Human Rights Commission is now monitoring illicit movement and dumping of toxic waste

Some international focus and collaboration Basel Convention on Control of Trans-boundary Movement

of Hazardous Waste and Disposal (1989) Stockholm Convention on Persistent Organic Pollutants

(2001) Strategic Approach to International Chemicals Management

(2006) Control and clean up measures have potential for

building confidence and collaboration in former conflict regions

FUTURE WASTE MANAGEMENT NEEDS

Avoidance of dumping Ongoing research on cause and effect interactions

between chemicals and human health Improved technology for risk assessment International strength to enforce regulation Corporate and social responsibility Increased participation of those affected by waste

sites Education Participation in governance process