APES – Chapter 30: Waste Management

Case Study – “e-waste”: A Growing Environmental Problem - The average computer life is 3 years > not constructed with recycling in mind - The U.S. produces most of the world’s e-waste; computer parts include small amounts of heavy

metals such as gold, tin, copper, calcium, and mercury which are toxic and can cause cancer if breathed/ingested

- The EPA has no protocol to make sure e-waste does not become a future problemo ‘Recycling’ is a very broad term when it comes to e-waste

- Most tech is exported to other countries like Nigeria and Chine > Guiyu (located in Hong Kong) processes more than 1 million tons of e-waste per year with little protection/protocol for workers

- Domestic recycling plants cannot recycle tech without charging a hefty fee > most companies simply ship the waste out of the country due to cheaper costs

o Guiyu makes $1 million dollars per year- The people of Guiyu and other areas simply are not aware of the dangers of the toxic materials

they sift through to find raw materials > the central government is reluctant to regulate/interfere because of the income

- The U.S. is the only major nation that has not ratified protocol banning exports or e-waste- Some companies are now processing materials in order to regain valuable materials > gold- The European Union is taking a more aggressive stance > hopefully….

Early Concepts of Waste Disposal Start of Industrial Revolution, the volume of waste produced in the US was relatively small.

o Managed through the concept of “dilute and disperse.” Factories located near water.

o Easy transport of materials by boato Sufficient water for processing and cooling o Easy disposal of waste into the river

Few factories and a sparse populationo Method was sufficient to remove the waste from the immediate environment.

As industrial and urban areas expanded, the concept became “concentrate and contain”o Containment not always achieved. o Containers leak or break and allow waste to escape.

People are facing a serious solid-waste disposal problem. o We are producing a great deal of waste and the acceptable space for permanent disposal is

limited.o Difficult to site new landfills (NIMBY).

Modern Trends Environmentally correct concept is to consider wastes as resources out of place.

o Waste would be a resource to be used again. o Referred to as the “zero waste” movement.

Industrial ecologyo Study of relationships among industrial systems and their links to natural systems. o Waste from one part of the system would be a resource for another part.

Countries have moved to cut waste by imposing taxes.

Tommy Hicks

APES – 6th period

o Taxation of waste in all its various forms, from emissions from smokestacks to solids delivered to landfills.

o As taxes increase people produce less waste. Landfills produce methane gas which can be burned as fuel.

Integrated Waste Management A set of management alternatives that includes:

o Reuseo Source reduction

o Recyclingo Compostingo Landfillo Incineration

Reduce, Reuse, Recycle Ultimate objective of the three R’s is to reduce. Study of the waste stream in areas that utilize IWM technology suggests that the amount of refuse

disposed of in landfills or incinerated can be reduced by at least 50% Reduction facilitated by

o Better design of packaging to reduce waste, an element of source reduction (10% reduction).o Large-scale composting programs (10% reduction).o Establishment of recycling programs (30% reduction).

Recycling is a major player in the reduction of urban waste stream.o Estimated that as much as 80-90% of the US waste stream might be recovered through intense

recycling.o Partial recycling can provide a significant reduction ~50%.o Simplified by single stream recycling.

Public Support for Recycling Encouraging signs

o An increase in the willingness of industry and business to support recycling on a variety of scales.

o People are now more likely to purchase products that can be recycled or that come in containers that are more easily recycled or composted.

Markets for Recycled Products In communities where recycling has been successfully implemented, it has resulted in glutted markets

for the recycled products. If recycling is to be successful,

o markets and processing facilities will also have to be developed to ensure that recycling is a sound financial venture.

Recycling of Human Waste The use of human waste or “night soil” on croplands is an ancient practice.

o Early uses of human waste for agriculture occasionally spread infectious diseases.o One of the major problems of recycling human waste today is that thousands of chemicals and

metals flow through our waste stream.o Because many toxic materials are likely to be present with the waste, we must be very skeptical

of utilizing sewage sludge for land application. Materials Management Futuristic waste management has the goal of zero production of waste.

o Consistent with the ideals of industrial ecology.o Goal will require more sustainable use of materials combined with resource conservation in

what is being termed materials management. The goal could be pursued in the following ways:

o Eliminate subsidies for extraction of virgin materials.o Establish “green building” incentives that encourage the use of recycled-content materials and

products in new construction.o Assess financial penalties for production that uses negative materials management practices.o Provide financial incentives for industrial practices and products that benefit the environment

by enhancing sustainability.o Increase the number of new jobs in the technology of reuse and recycling of resources.

Solid-Waste Management Continues to be a problem in many parts of the world.

o Many practices inadequate. Open dumps, illegal roadside dumping

o Social problem as much as a physical one, because many people are simply disposing of their waste as inexpensively and as quickly as possible.

Composition of Solid Waste Paper is by far the most abundant content. Excavations into modern landfills using archeological tools have cleared up some misconceptions

concerning other items. o Fast-food packaging accounts for about 0.25% of the average landfillo Disposable diapers, approximately 0.8%o Polystyrene products, about 0.9%

On-Site Disposal A common on-site disposal method in urban areas is the mechanical grinding of kitchen food waste.

o Garbage-disposal devices are installed at the kitchen sink, and the garbage is ground and flushed into the sewer system.

Composting Biochemical process in which organic materials decompose to a rich, soil-like material.

o The process involves rapid partial decomposition of moist solid organic waste by aerobic organisms.

As a waste management option, large-scale composting is generally carried out in the controlled environment of mechanical digesters.

Incineration

Combustible waste is burned at temperatures high enough (900°–1,000°C, or 1,650°–1,830°F) to consume all combustible material.

o Leaving only ash and non-combustibles to dispose of in a landfill. Process of incineration can be used to supplement other fuels and generate electrical power. In modern incineration facilities, smokestacks are fitted with special devices to trap pollutants. Open Dumps In the past, solid waste was often disposed of in open dumps, where the refuse was piled up without

being covered or otherwise protected.o Located wherever land is available, without regard to safety, health hazards, or aesthetic

degradation. Common sites

o Abandoned mines and quarries, natural low areas, such as swamps or floodplains; and hillside areas above or below towns.

Sanitary Landfills Designed to concentrate and contain refuse w/o creating a nuisance or hazard to public health or

safety. o Confined to the smallest practical areao Reduced to the smallest practical volume o Covered with a layer of compacted soil at the end of each day of operation.

Leachate The most significant hazard from a sanitary landfill is pollution of groundwater or surface water.

o If waste comes into contact with water, leachate is produced. noxious, mineralized liquid capable of transporting bacterial pollutants

Site Selection A number of factors must be taken into consideration when selecting a site, including:

o Topographyo Location of the groundwater tableo Amount of precipitationo Type of soil and rocko Location of the disposal zone in the surface water and groundwater flow system.

Best sites are arid sites The waste is buried above the water table in relatively impermeable clay and silt soils.

o Leachate produced remains in the vicinity of the site and degrades by natural filtering action. Site selection also involves important social considerations.

o Chosen where they expect local resistance to be minimal or where they perceive land to have little value.

o Frequently located in areas of low socioeconomic status Monitoring Pollution in Sanitary Landfills Once a site is chosen for a sanitary landfill and before filling starts, monitoring the movement of

groundwater should begin. o Accomplished by periodically taking samples of water and gas from specially designed

monitoring wells. o Monitoring the movement of leachate and gases should continue as long as there is any

possibility of pollution.

How Pollutants Can Enter the Environment from Sanitary Landfillso 1. Methane, ammonia, hydrogen sulfide, and nitrogen gases can be produced from compounds

in the soil and the waste and can enter the atmosphere.o 2. Heavy metals, such as lead, chromium, and iron, can be retained in the soil.o 3. Soluble materials, such as chloride, nitrate, and sulfate, can readily pass through the waste

and soil to the groundwater system.o 4. Overland runoff can pick up leachate and transport it into streams and rivers.o 5. Plants growing in the disposal area can selectively take up heavy metals and other toxic

materials. o Passed up the food chain as people and animals eat the plants.o 6. If plant residue return toxic substances to the soil.o 7. Streams and rivers may become contaminated by waste from groundwater seeping into the

channel (3) or by surface runoff (4).o 8. Toxic materials can be transported to other areas by the wind.

Modern sanitary landfills are engineered to include multiple barriers: o Clay and plastic liners to limit the movement of leachateo Surface and subsurface drainage to collect leachateo Systems to collect methane gas o Groundwater monitoring to detect leaks of leachate below and adjacent to the landfill.

Federal Legislation for Sanitary Landfills

Resource Conservation and Recovery Act of 1980. o Legislation intended to strengthen and standardize design, operation, and monitoring of

sanitary landfills. Landfills that cannot comply with regulations face closure. States may choose between two options:

o 1. Comply with federal standards.o 2. Seek EPA approval of solid-waste management plans, which allows greater flexibility.

Provisions of federal standards include the following:o Landfills may not be sited on floodplains, wetlands, earthquake zones, unstable land, or near

airports.o Landfills must have liners.o Landfills must have a leachate collection system.o Landfill operators must monitor groundwater for many specified toxic chemicals.o Landfill operators must meet financial assurance criteria to ensure that monitoring continues

for 30 years after the landfill is closed. EPA approval of its landfill program:

o Groundwater monitoring may be suspended.o Alternative types of daily cover over the waste.o Alternative groundwater protection standards and schedules for documentation are allowed.o Under certain circumstances, landfills in wetlands and fault zones are allowed.o Alternative financial assurance mechanisms are allowed.

Hazardous Waste In the US, approximately 1,000 new chemicals are marketed each year, and about 70,000 chemicals are

currently on the market. o 35,000 chemicals used are classified as definitely or potentially hazardous to the health of

people or ecosystems. The US currently produces about 700 million metric tons of hazardous chemical waste per year,

referred to more commonly as hazardous waste. Uncontrolled dumping of chemical waste has polluted soil and groundwater in several ways:

o Chemical waste may be stored in barrels.The barrels eventually corrode and leak.o When liquid chemical waste is dumped into an unlined lagoon, contaminated water may

percolate through soil and rock to the groundwater table.o Liquid chemical waste may be illegally dumped in deserted fields or even along roads.

Resource Conservation and Recovery act Passed in 1976

o Identification of hazardous wastes and their life cycles.o “Cradle to grave” management

The act classifies hazardous wastes in several categories: o Materials highly toxic to people and other living things; o Wastes that may ignite when exposed to air;o Extremely corrosive wasteso Reactive unstable wastes that are explosive or generate toxic gases or fumes when mixed with

water. Comprehensive Environmental Response, Compensation, and Liability Act

Passed in 1980o Act defined policies and procedures for release of hazardous substances into the environment.o Mandated development of a list of the sites where hazardous substances were likely to or

already had produced the most serious environmental problemso Established a revolving fund (Superfund) to clean up the worst abandoned hazardous-waste

sites. Strengthened by amendments that made the following changes:

o Improved and tightened standards for disposal and cleanup of hazardous waste.o Banned land disposal of certain hazardous chemicals.o Initiated a timetable for phasing out disposal of all untreated liquid hazardous waste in landfills

or surface impoundments.o Increased the size of the Superfund.

Hazardous-Waste Management Land Disposal Management of hazardous chemical waste involves several options, including:

o Recyclingo On-site processing to recover by-products with commercial valueo Microbial breakdowno Chemical stabilizationo High-temperature decompositiono Incinerationo Disposal by secure landfill or deep-well injection

Secure Landfill A secure landfill for hazardous waste is designed to:

o Confine the waste to a particular location

o Control the leachate that drains from the wasteo Collect and treat the leachateo Detect possible leaks

This type of landfill is similar to the modern sanitary landfill.

Land Application: Microbial Breakdown Intention application of waste materials to surface soil.

o May be a desirable method of treatment for certain biodegradable industrial wastes.o A good indicator of the usefulness of land application for a particular waste is the

biopersistence of the waste. How long the material remains in the biosphere. Greater the biopersistence, the less suitable for land application

Land application of biodegradable waste works because, o when materials are added to the soil, they are attacked by microflora that decompose the

waste material in a process known as microbial breakdown. Surface Impoundment Both natural topographic depressions and human-made excavations formed primarily of soil or other

surface materials but lined with manufactured materials such as plastic. o Examples include aeration pits and lagoons at hazardous-waste facilities.o Prone to seepage, resulting in pollution of soil and groundwater.o Evaporation from surface impoundments can also produce an air pollution problem.

Deep Well Disposal A deep well penetrates to a depth below and completely isolated from all freshwater aquifers.

o Waste is injected into a permeable rock layer several thousand meters below the surface in geologic basins.

o Capped by relatively impervious, fracture-resistant rock such as shale or salt deposits. Important control of water pollution in oil fields.

o Injection of oil field brine. Should not be viewed as a quick and easy solution to industrial waste problems. Alternatives to Land Disposal of Hazardous Wastes Advantages to source reduction, recycling, treatment, and incineration include the following:

o Useful chemicals can be reclaimed and reused.o Treatment of wastes may make them less toxic and therefore less likely to cause problems in

landfills.o The actual waste that must eventually be disposed of is reduced to a much smaller volume.o Because a reduced volume of waste is finally disposed of, there is less stress on the dwindling

capacity of waste-disposal sites. Source Reduction

o The object is to reduce the amount of hazardous waste generated by manufacturing or other processes.

Recycling and resource Recoveryo May contain materials that can be recovered for future use.

Treatmento Waste can be treated by a variety of processes to change the physical or chemical composition

of the waste and so to reduce its toxic or hazardous characteristics. Incineration

o Destroyed by high-temperature incineration. Incineration is considered a waste treatment rather than a disposal method because the process

produces an ash residue, which must then be disposed of in a landfill. Ocean Dumping Oceans have long been dumping grounds for many types of waste, including industrial waste,

construction debris, urban sewage, and plastics Many locations in the world’s oceans are

o Accumulating pollution continuouslyo Have intermittent pollution problemso Or have potential for pollution from ships in the major shipping lanes

Marine pollution has a variety of specific effects on oceanic life, including the following:o Death or retarded growth, vitality, and reproductivity of marine organisms.o Reduction in the dissolved oxygen content necessary for marine life because of increased BOD.o Eutrophication caused by nutrient-rich waste in shallow waters of estuaries, bays, and parts of

the continental shelf.o Habitat change caused by waste-disposal practices that subtly or drastically change entire

marine ecosystems. Microlayer

o The upper 3 mm of ocean water.o Planktonic life abundant (base of the marine food chain)o Home to young fish and shellfish in the early stages of their life.

Microlayer also tends to concentrate pollutants, such as toxic chemicals and heavy metals. Fear that disproportionate pollution will have especially serious effects on marine organisms. Marine pollution can have major impacts on people and society.

o Contaminated marine organisms may transmit toxic elements or diseases to people who eat them.

o When beaches and harbors become polluted there may be damage to marine life as well as a loss of visual appeal and other amenities.

o Economic loss is considerable. Tourism and fishing industry

Pollution Prevention Involves identifying ways to prevent the generation of waste rather than finding ways to dispose of it. Approaches include:

o Purchasing the proper amount of raw materials so that no excess remains to be disposed of.o Exercising better control of materials used in manufacturing processes so that less waste is

produced.o Substituting nontoxic chemicals for hazardous or toxic materials currently in use.

o Improving engineering and design of manufacturing processes so that less waste is produced.