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Waste Generation and Waste Disposal

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1 Waste Generation and Waste Disposal
Chapter 16 Waste Generation and Waste Disposal

2 The Throw Away Society Until a society becomes relatively wealthy, it generates little waste. Every object that no longer serves it original purpose becomes useful for something else. 1900s US – Junk dealers or scrap metal dealers – no one called it recycling back then After World War II – rapid population growth in US led to increased consumption patterns Increasing industrialization and wealth, as well as cultural changes, made it possible for people to purchase household conveniences that could be used and thrown away. Planned Obsolescence – the design of a product so that it will need to be replaced within a few years Everything from toasters to cars TV dinners, throw-away napkins, disposable plates and forks United States became the leader of what came to be known as a “throw-away society.” Planned obsolescence – most significant contributor to this.

3 Municipal Solid Waste Municipal Solid Waste (MSW) - Refuse collected by municipalities from households, small businesses, and institutions such as schools, prisons, municipal buildings and hospitals. Residences – 60% Commercial – 40% Waste generation varies by season of the year, socioeconomic status of the individual, and geographic location within the country.

4 Containers and packaging comprise the greatest amount of MSW

5 E-Waste Electronic waste (E-waste) televisions, computers, cell phones that contain toxic metals. Older cathode-ray tube (CRT) television or computer monitors contains 1-2 kg ( lbs) of the heavy metal lead as well as other toxic metals such as mercury and cadmium. Costs more to recycle a computer than put it in a landfill In US, most electronic devices are not designed to be easily dismantled after they are discarded. Much E-waste from US is exported to China where adults and children separate valuable metals using fire and acids with no protective clothing or respiratory gear.

6 Reduce, Reuse, Recycle Reduce- waste minimization or prevention
Source reduction – seeks to reduce waste by reducing, in the early stages of design and manufacture, the use of materials – toxic and otherwise – destined to become MSW. A company that produces laundry detergent switches from distributing its product in plastic bottles to instead using flexible pouches that require 84% less packaging. Reuse- reusing something like a disposable cup more than once Flea markets, eBay, Craigslist, and Freecycle

7 Reduce, Reuse, Recycle Recycle- materials are collected and converted into raw materials and then used to produce new objects Closed-loop recycling – recycling of a product into the same product Aluminum cans Open-loop recycling – one product (plastic soda bottles) Is recycled into another product (polar fleece jackets). Avoids sending materials to the landfill, but does not reduce demand for raw materials (ex. Petroleum), to make new bottles Single stream or zero-sort recycling – allow residents to mix all types of recyclables in one container. Sorting facility workers sort materials in categories that are in the greatest demand at a given time and offer greatest economic return. Pine Grove Area School District - The recycling collected at your school goes to a transfer station in Coal Township. There it is loaded into a 53 foot trailer and transported to a facility in Philadelphia. One of the greatest problems with recycling – there is not always a market for recycled goods

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10 Composting Compost- organic material that has decomposed under controlled conditions to produce an organic-rich material. Roughly 33% of current MSW could be composted Benefits of Composting: reduced volume of material ending up in a landfill generation of rich organic fertilizer reduced amount of methane generated in landfills reduced amount of energy needed to transport material to a landfill

11 Landfills Sanitary landfills- engineered ground facilities designed to hold MSW with as little contamination of the surrounding environment as possible. Primary method of disposal for MSW in US Constructed with clay or plastic lining at the bottom Clay used because it can stop water flow and retain positively charged ions, like metals. Pipes constructed to collect leachate and methane Methane could be extracted and used as fuel or burned off Leachate- the water that leaches through the solid waste and removes various chemical compounds with which it comes into contact. Could be extracted and transported to a wastewater treatment facility Cover of soil and slay, called a cap, installed when landfill reaches capacity. MSW periodically compacted into cells – reduces the volume of solid waste – increases capacity of landfill. Closed landfill can be reclaimed – planted with shallow-rooted plants – parks, playgrounds, golf courses Tipping fees – each truck put on a scale, and after MSW is weighed it is tipped into the landfill Reimburses construction fee of landfill

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13 Choosing a Sanitary Landfill Site
Should be located in a soil rich in clay to reduce the migration of contaminants. Located away from rivers, streams, and other bodies of water and drinking water supplies. Far from population centers, however, as distance increases so does amount of energy required Regional landfills becoming more common – greatest economic advantage Siting – designation of a location – always controversial and sometimes politically charged Unsightliness and odor Have been the source of considerable environmental injustice NIMBY – “Not-in-my-backyard” attitude – People with financial resources or political influence A site may be chosen not because it meets safety criteria but because its neighbors lack the resources to mount a convincing opposition.

14 Problems with Landfills
Always a possibility that leachate will contaminate waterways. EPA estimates that virtually all landfills in the US have some leaching. When waste is compacted into cells and covered with soil, all the oxygen is used up. Anaerobic decomposition begins, which generates methane and CO2 – both greenhouse gases. Methane also creates an explosion hazard – landfills are vented so methane does not accumulate Professor William Rathje – University of Arizona – used bucket auger to obtain information on the decomposition rates of MSW in landfills. Found newspapers with headlines still legible 40 years after being deposited in landfills. Decomposition only takes place where correct mixture of air, moisture, and organic matter are present – most landfills do not contain this and will probably remain the sizes they were when capped.

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16 Incineration Incineration- the process of burning waste materials to reduce its volume and mass and sometimes to generate electricity and heat. Waste heat and fly ash formed as byproducts of incineration. Ash – residual nonorganic material that does not combust during incineration Bottom ash – collected underneath the furnace Fly ash – residue collected beyond the furnace Disposal of the ash is determined by concentration of toxic metals – lead and cadmium If deemed safe could be used as fill in road construction or as an ingredient in cement blocks and cement flooring Incineration of certain materials (plastic) could release acidic gases such as hydrogen chloride (HCl), which are recovered in a scrubber, neutralized and disposed of in a landfill. Waste heat – when heat generated by incineration is used rather than released to the atmosphere it is called a waste-to-energy system.

17 Incineration Problems
High tipping fees to cover construction and operation. Raises NIMBY and environmental justice issues May release pollutants, such as organic compounds from incomplete combustion of plastics and metals. Expensive to build so they require large quantities of daily MSW to be profitable. May not completely burn all waste Plant operators can monitor oxygen and temperature of the burn – everything lumped together – difficult for uniform burn

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19 Hazardous Waste Hazardous waste- liquid, solid, gaseous, or sludge waste material that is harmful to humans or ecosystems. According to EPA, over 20,000 hazardous waste generators in the US produce about 40 million tons of hazardous waste/year. By-product of industrial processes such as textile production, machinery cleaning, computer manufacturing, small businesses (dry cleaners), automobile service stations, and small farms. Collection sites for hazardous waste must be staffed with specially trained personnel. Hazardous waste must be treated before disposal.

20 Laws Resource Conservation and Recovery Act (RCRA)- designed to reduce or eliminate hazardous waste. Also know as “cradle-to-grave” tracking. RCRA ensures that hazardous waste is tracked and properly disposed of. Main goal is to protect human health and the natural environment by reducing or eliminating the generation of hazardous waste.

21 Laws Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)- also know as “Superfund”. Puts a tax on the chemical and petroleum industries. This revenue is used to cleanup abandoned and nonoperating hazardous waste sites where a responsible party cannot be found. Requires the federal government to respond directly to the release of substance that may pose a threat to human health or the environment EPA maintains the National Priorities List (NPL) of contaminated site eligible for cleanup funds. October 2010 – 1,282 Superfund sites – one in every state except North Dakota NJ has 114 followed by CA and PA with the next highest number. Love Canal, NY

22 Brownfields Contaminated industrial or commercial sites that may require environmental cleanup before they can be redeveloped or expanded. Old factories, industrial areas and waterfronts, dry cleaners, gas stations, landfills, and rail yards are some examples. Seattle’s Gasworks Park – previously used as a coal and oil gasification plant – purchased by the city in 1962 to rehabilitate the site into a park. Underwent chemical abatement and environmental cleanup – now distinctive landmark for the city Criticized as an inadequate solution – managed entirely by state and local governments – varies widely between regions Lacks legal liability controls to compel polluters to rehabilitate their properties Without legal recourse many brownfields sites remain unused and contaminated

23 International Consequences
Difficult to dispose of – hazardous waste often sent to countries with less stringent regulations Garbage and ash barges travel the oceans looking for a developing country willing to accept hazardous waste from the US in exchange for cash payment. Khian Sea – cargo vessel that left Philadelphia in 1986 with almost 13,000 metric tons of hazardous ash from an incinerator. Traveled to a number of countries in the Caribbean – some ash dumped in Haiti, some dumped in the ocean In 1996, US ordered that the ash be retrieved and removed from Haiti and returned to the US Held at a dock in FL – ash was deemed nonhazardous by the EPA and in 2002 was placed in a landfill in Franklin County, PA – not far from its source of origin.

24 Life Cycle Analysis Life-cycle Analysis – an important systems tool that looks at the materials used and released throughout the lifetime of a product – from the procurement of raw materials through their manufacture, use, and disposal. Often called cradle-to-grave analysis Paper vs. Styrofoam cup in opening story

25 Integrated Waste Management
A method that seeks to develop as many options as possible, to reduce environmental harm and cost. Reduction, recycling, composting, landfills, and incineration are some ways IWM is utilized. Behavior related to use and disposal is considered and possibly altered in order to obtain the desired outcome – LESS GENERATION OF MSW. Volkswagen – manufactures some of its cars so that they can be easily taken apart and materials of different composition easily separated to allow recycling.


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