Waste Generation and Waste Disposal

Waste Waste – nonuseful products generated within the system throw-away society Municipal Solid Waste (MSW) - everyday items that we use and then throw away (“trash, garbage”) - waste stream Waste stream – all products wear out, lose their value, or are discarded; this is the flow of solid waste that is recycled, incinerated, placed in a solid waste landfill or disposed of in another way

A – before recycling, paper makes up the majority of MSW B – containers and packaging make up the largest for MSW that is typically used once

The Three R’s “Reduce, Reuse, Recycle” Reduce a. optimal way of achieving a reduction in solid waste generation b. source reduction * Used to divert materials from the waste stream

Reuse a. allows material to cycle within a system longer before becoming an output b. no additional energy or resources needed Recycle a. MSW collected and converted into new objects b. closed-loop - aluminum cans c. open-loop - plastic bottles into fleece jackets d. requires more energy than the other R’s e. last choice among the 3 R’s

a. used for organic matter b. allows for controlled decomposition Compost a. used for organic matter b. allows for controlled decomposition c. produces material that enhances soil structure, CEC, and fertility d. layer dry (brown) with wet (green) material, rotate regularly - provides ideal C:N ratio If you put organic material in landfill, it decomposes anaerobically producing methane (CH4)

Landfills and Incineration a. hold MSW with very little contamination of the surrounding environment

a. clay or plastic lining at the bottom b. pipes collect leachate Structure of landfill a. clay or plastic lining at the bottom b. pipes collect leachate c. soil or clay is used to cover landfill when it reaches it’s capacity (can be reclaimed) d. must control inputs e. “tipping fee” 1. economic incentive 2. recyclables - no charge Rainfall or other water inputs is minimized because excess water can lead to anaerobic decomposition at a greater rate releasing larger amounts of methane Leachate that is not captured by the pipes can possible leach into nearby soils and groundwater Inputs a. best materials are ones that have the least possible impact on the environment meaning they are least likely to generate leachate and produce methane b. aluminum and copper should never go into a landfill c. glass and plastics are good as long as they are not able to be recycled or reused d. anything with large amounts of metals cannot be in landfill

Landfill siting a. soil rich in clay b. located away from sources of water and drinking supplies c. far from population centers d. consider amount of energy needed to get trucks there

Problems with landfills a. global problem – locating near populations that do not have the resources to object b. leachate contaminating water c. methane (CH4) - explosion hazard - can be used to generate electricity Landfills

Incineration a. burning waste to reduce volume and mass c. occasionally used for electricity d. volume – 90% weight – 75%

Structure of waste-to-energy incinerator a. MSW “tipped” onto platform b. transferred to furnace c. waste converted into CO2 and H2O and released into atmosphere d. ash - fly ash - bottom ash Ash can be disposed of but is dependent upon its concentration of toxic metals such as lead and cadmium. Ash can be used to fill in road construction as well as an ingredient in cement blocks and cement flooring If the heat isn’t released into the atmospere it is considered waste-to-energy

Problems with Incinerator a. tipping fees charged b. produce ash (very toxic) c. require large amounts of MSW in order to burn efficiently

Hazardous Waste “liquid, solid, gaseous, or sludge waste material that is harmful to humans or ecosystems” Textile production, cleaning of machinery, manufacturing of computer equipment * Only about 5% of hazardous waste produced is recycled in the US.

Handling hazardous waste a. must be treated before disposal b. treatment 1. making it less harmful to environment 2. altered through series of chemical procedures c. best option: substitute for other products or use less of product

Legislative action to hazardous waste a. Resource Conservation and Recovery Act (RCRA) - protect human health and natural environment by reducing/eliminating the generation of hazardous waste - EPA maintains list of hazardous wastes used by businesses, track it for proper disposal - modified by Hazardous and Solid Waste Amendment (HSWA) to encourage waste minimization and phase out disposal of hazardous waste on land; also increased law enforcement authorities (punishment)

b. Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) - “Superfund Act” - imposes tax on chemical and petroleum industries - revenue from tax used to cleanup abandoned and nonoperating hazardous waste sites - authorizes federal government to response directly to release of substances that may pose a threat to human health or environment - EPA maintains National Priorities List (NPL) of contaminated sites that are eligible for cleanup funds * Superfund Site – Love Canal, New York Love Canal Originally a landfill for hazardous waste and was filled and then used for a school and housing development later on there were large number of illnesses due to benzene and trichloroethylene that were found in the basements of the homes Atracted national attention and people were evacuated

c. Brownfields 1. used to assist state and local governments in cleaning up contaminated sites (actual program) 2. contaminated sites that require cleanup before being redeveloped or expanded ex) old factories, gas stations, dry cleaners 3. can sometimes remain used and contaminated Since they are ran by only state and local, the legislative actions can vary from region to region meaing that sometimes they don’t have liability controls making them remain used and contaminated

New Approaches to handling waste a. Life-Cycle analysis 1. “cradle-to-grave analysis” b. Integrated Waste Management 1.waste reduction management 2. disposal strategies 3. biggest emphasis – source reduction