Chapter 30

Waste Management

Early Waste Disposal

• First part of Industrial Revolution: not much waste – relatively small

• “Dilute and Disperse”

• Factories were built near rivers for:– Easy transport of materials– Sufficient water for processing & cooling– Easy disposal of waste in river

Early – Cont’d

• As industry & urban areas expanded:

• “Concentrate and Contain”– Trenches in ground– Metal drums

• Leakages

• Major waste disposal problems

AS A RESULT

• Running out of landfill space --- existing sites are filling up and new sites are difficult to get approved

• NIMBY

• Cost- 10 yrs ago – 1 metric ton = $5-$10 now - $40 or even $75 in cities.

Modern Trends• Industrial Ecology

– The study of relationships among industrial systems and their links to natural systems

– Waste is a resource “Out of Place”

– “ZERO WASTE”

– Recycle waste for other uses.

Integrated Waste Management

• Includes:– Reduce, reuse, recycle– Composting– Landfill– Incineration

Reduce, Reuse Recycle

• Reduce the amt. of urban waste that is disposed in landfills, incinerated or disposed of in other ways.

• 50% reduction can be facilitated by:– Better design of packaging– Large scale composting– Recycling programs

• Today most areas recycle about 30% of waste

• With intense recycling it is thought that 80 – 90% of waste could be recycled.

Public support for Recycling

• Fast food restaurants use less packaging & on-site recycling for paper & plastic

• Grocery stores using paper and canvas shopping bags

• Companies redesigning products so that they are more easily disassembled. (Toasters, washing machines & automobiles)

ReUse

• Refillable water containers– Petroleum based– 1000 yrs to break down– 2,000,000 plastic bottles thrown away every

HOUR !!!

Materials Management

• A visionary goal requiring more sustainable use of materials combined with resource conservation– Eliminate subsides for extraction of virgin materials –

this doesn’t encourage recycling

– Establish “green building” incentives – use recycled materials

– Assess financial penalties – poor materials mgmt.

– Provide financial incentives – benefits to the environ.

– Increase new jobs

Examples:

• Steel Mills are located in California and Nebraska– Resource = scrap metal

• Paper Mill & Steel Mill in New Jersey– Resource = recycled paper and scrap metal

– 50% of steel currently comes from scrap

Recycling

• Primary: converted into new products of the same type. – Ex: aluminum cans are recycled to produce

more aluminum cans

• Secondary: converted to a different type of product.– Ex: rubber tires converted to rubberized road

surface material

Recycling• Advantages

– Reduces greenhouse gases– Reduces need for mining material– Decreases water pollution– Reduces solid waste production & disposal

• Disadvantages– Decreases jobs& profits at landfills and

incinerators– Expensive compared to landfills– Money generated from glass & plastic is

reduced

Solid-Waste Management

• Composition

• On-Site Disposal

• Composting

• Incineration

• Open Dumps

• Sanitary Landfills

Activity

Read : Case Study (pg. 645) and Summarize

COMPOSITION:

Copy Pie Chart on Page650 of the text

On-Site Disposal

• Garbage Disposal– Grinding kitchen waste

Composting

• Biochemical process in which organic materials decompose to rich, soil-like material

• Disadvantage: composting plant debris previously treated with herbicides or fertilizers.

Incineration• Combustible waste burned at temps high

enough (1650o – 1830o)to consume all combustible materials, leaving only ash & non-combustibles for disposal in landfills.

• Proposed to reduce the volume of waste by 90%. Actually reduces approx. 50%

• Produces heat that can then be used to produce electricity

Incineration Cont’d• Disadvantage:

– Creates greenhouse gas emissions – CO2– Releases air pollutants- nitrogen oxides, sulfur

dioxides, mercury & dioxins• Scrubbers are used to eliminate this…

– Creates large amts. of ash, that must be landfilled

– Expensive to build and operate. Cost is 2x that of landfills

Open Dumps• Refuse is piled up without being covered.

• Located wherever land is available w/o regard to safety, health hazards or aesthetic degradation.

• Common sites: abandoned mines/quarries, natural low lying areas or below towns.

• Unsightly, breeding ground for pests, air pollution, groundwater pollution

Sanitary Landfills• Municipal Solid Waste Landfill

• Designed to concentrate and contain refuse w/o creating a nuisance or hazard to public health or safety.

• Confine waste to smallest volume within the smallest area

• Cover with a thin layer of soil.– THIS IS WHAT MAKES IT SANITARY !!– Restricts access to the waste…

Sanitary Landfills• Must meet specific federal req. mandated

by the Resource Conservation and Recovery Act for location, design, operation, closure, monitoring and financial assurance.

• Constructed with special liners & impermeable soil layers to prevent leaching into local water supplies.

• Procedures must be in place to monitor and control leaks.

Sanitary Landfill Disadvantages• Landfills release greenhouse gases

(methane and CO2) as wastes decompose.

• Toxic materials leach out of landfill as liquid draws it downward. (LEACHATE)– Leachate can make its way to the groundwater

• Air Pollution is generated from the landfill and the trucks transporting the waste.

Landfills & Sustainability• Use clay and plastic liners to prevent leaks

• Use piping to collect leachate

• Have leachate storage tanks & treatment in place

• Collect methane for fuel for electrical generation

• Monitor groundwater for toxins from leachate.

Sanitary Landfill

– LOCATION, LOCATION, LOCATION !!!• CAN’T FIND ONE !!!

• Major drawback is a suitable location.

• Need landfills in highly populated areas– Land is scarce & expensive

• Best place is arid and away from surface or groundwater.

Landfill - Bottom line

• May not be sited on floodplains, wetlands, earthquake zones, unstable land or airports

• Must have liners

• Must have a leachate collection system

• Operators must monitor groundwater

• Monitoring must continue for 30 yrs after landfill is closed

Hazardous Waste

• Waste that is classified as definitely or potentially hazardous to the health of people

• Often corrosive, flammable or dangerously chemically reactive

Hazardous Waste Legislation– Know these acts, terms, places -

• Resource Conservation and Recovery Act• CERCLA High level radioactive• Environmental Audit waste• Secure Landfill• Land Application• Surface Impoundment• Deep-Well Disposal• Love Canal• Integrated Waste mgmt• Major classes of hazardous waste

Alternatives to Hazardous Waste

• Source reduction, Recycling and resources recovery, Treatment, Incineration

• Advantages– Chemicals can be reused– Less toxic = less problems– Smaller volume of waste– Less stress of waste disposal sites

Ocean Dumping

• Types of Waste– Dredge spoils

– Industrial wastes

– Sewage sludge

– Construction debris

– Solid waste

• The most seriously affected areas are near shore