1 chapter 13 solid & hazardous waste. 2 outline: solid waste waste disposal methods shrinking the...
Post on 17-Jan-2016
Embed Size (px)
Chapter 13Solid & Hazardous Waste
Outline:Solid WasteWaste Disposal MethodsShrinking the Waste StreamRecyclingHazardous and Toxic WastesFederal LegislationRCRACERCLAManagement Options
WASTEAccording to EPA, U.S. produces 11 billion tons of solid waste annually.About half is agricultural waste.More than one-third is mining related.Industrial Waste - 400 million metric tons.Hazardous/Toxic - 60 million metric tons.Municipal Waste - 230 million metric tons.Two kg per person / per day.Waste Stream
U.S. Domestic Waste
WASTE DISPOSAL METHODSOpen DumpsOpen, unregulated dumps are 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.Five times volume of Exxon Valdez.
WASTE DISPOSAL METHODS CONTDLandfillsSanitary Landfills Refuse compacted and covered everyday with a layer of dirt.Dirt takes up as much as 20% of landfill space.Since 1994, all operating landfills in the U.S. have been required to control hazardous substances.
LandfillsHistorically, landfills have been a convenient, inexpensive waste-disposal option.Increasing land and shipping fees, and demanding construction and maintenance requirements are increasing costs.Suitable landfill sites are becoming scarce.Increasingly, communities are rejecting new landfills.Old landfills are quickly reaching capacity and closing.
Fresh Kills Landfill (1947 2001)Opened as a "temporary landfill" in 1947, The Fresh Kills Landfill covers 2200 acres, can be seen with the naked eye from space and is taller then the Statue of Liberty, at a height of 225 ft.
It is situated on the western shore of Staten Island and is made up of four sections which contain fifty plus years of landfill, mostly in the form of household waste.
The waste disposed at the Fresh Kills Landfill and the decomposition products of this waste contain numerous chemicals.
The chemicals can enter into the environment in a variety of ways: releases into the air from barge unloading and garbage trucks unloading; the cement crushing trucks releases chemical dust into the air; and into the local groundwater by leaching.
WASTE DISPOSAL METHODS CONTDExporting WasteAlthough most industrialized nations have agreed to stop shipping hazardous and toxic waste to less-developed countries, the practice still continues.Garbage imperialism also operates in wealthier countries.Indian reservations increasingly being approached to store wastes on reservations.
WASTE DISPOSAL METHODS CONTDIncineration and Resource RecoveryEnergy Recovery - Heat derived from incinerated refuse is a useful resource.Steam used for heating buildings or generating electricity.
Incinerator TypesRefuse-Derived Fuel - Refuse is sorted to remove recyclable and unburnable materials.Higher energy content than raw trash.Mass Burn - Everything smaller than major furniture and appliances loaded into furnace.Creates air pollution problems.Reduces disposal volume by 80-90%.Residual ash usually contains toxic material.
Mass-Burn Garbage Incinerator
Incinerator Cost and SafetyInitial construction costs are usually between $100 and $300 million for a typical municipal facility.Tipping fess are often much higher than tipping fees at landfills.EPA has found alarmingly high toxin levels in incinerator ash.Concentrated in fly ash.Pollution control methods are not guaranteed to be 100% effective.
SHRINKING THE WASTE STREAMRecyclingRecycling is the reprocessing of discarded materials into new, useful products.Currently, about two-thirds of all aluminum cans are recycled.Half of all aluminum cans on grocery shelves will be made into another can within two months.
RecyclingPotential ProblemsMarket prices fluctuate wildly.ContaminationMost of 24 billion plastic soft drink bottles sold annually in the U.S. are PET, which can be melted and remanufactured into many items.But a single PVC bottle can ruin an entire truckload of PET if melted together.
U.S. Recycling Rates
Recycling ContdBenefitsSaves money, raw materials, and land.Encourages individual responsibility.Reduces pressure on disposal systems.Japan recycles about half of all household and commercial wastes.Lowers demand for raw resources.Reduces energy consumption and air pollution.
Recycling ContdBenefits ExampleRecycling 1 ton of aluminum saves 4 tons of bauxite, 700 kg of petroleum coke and pitch, and keeps 35 kg of aluminum fluoride out of the air.Producing aluminum from scrap instead of bauxite ore cuts energy use by 95%.Yet still throw away more than a million tons of aluminum annually.
SHRINKING THE WASTE STREAMCompostingBiological degradation of organic material under aerobic conditions.DemanufacturingDisassembly and recycling of obsolete consumer products.ReuseReusable glass container makes an average of 15 round-trips between factory and customer before it has to be recycled.
Earthworms are entirely good (beneficial) animals performing important functions in the soil that increase its fertility and improve its structure and aeration. They are valuable in treating waste, combating pollution and generally help to tidy the garden of leaves and other rotting vegetation. Worms take plant material and leaves into the soil where it rots and is eaten to form humus (humus contains nutrients). This aids soil structure. The burrows formed by worms aerate and break-up the soil helping drainage and creating space for plant root growth.An Active Compost Heap
Turning Over the Compost Heap
SHRINKING THE WASTE STREAM CONTDProducing Less WasteExcess packaging of food and consumer products is one of our greatest sources of unnecessary waste.Paper, plastic, glass, and metal packaging material make up 50% of domestic trash by volume.Increase use of photodegradable and biodegradable plastics.Too much emphasis on recycling?
HAZARDOUS AND TOXIC WASTESEPA estimates U.S. industries 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 each year.
Hazardous WasteLegally, 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.CorrosiveExplosive or highly reactive.
Hazardous Waste DisposalFederal LegislationResource Conservation and Recovery Act (RCRA) - 1976.Comprehensive program requiring rigorous testing and management of toxic and hazardous substances.Cradle to grave accounting.
Cradle to Grave
Federal LegislationComprehensive Environmental Response, Compensation and Liability Act (CERCLA).Modified in 1984 by Superfund Amendments and Reauthorization Act.Aimed at rapid containment, cleanup, or remediation of abandoned toxic waste sites.Toxic Release Inventory - Requires 20,000 manufacturing facilities to report annually on releases of more than 300 toxic materials.
CERCLAGovernment does not have to prove anyone violated a law, or what role they played in a superfund site.Liability under CERCLA is strict, joint, and several, meaning anyone associated with a site can be held responsible for the entire clean-up cost.
Superfund SitesEPA estimates 36,000 seriously contaminated sites in the U.S.By 2004, 1,671 sites had been placed on the National Priority List for cleanup with with Superfund financing.Superfund is a revolving pool designed to:Provide immediate response to emergency situations posing imminent hazards.Clean-up abandoned or inactive sites.
Superfund Sites ContdTotal costs for hazardous waste cleanup in the U.S. are estimated between $370 billion and $1.7 trillion.For years, most of the funding has gone to legal fees, but this situation has improved over past several years.Studies of Superfund sites reveal minorities tend to be over-represented in these neighborhoods.
How Clean is CleanBrownfields - Contaminated properties that have been abandoned or are not being used up to potential because of pollution concerns.Up to one-third of all commercial industrial sites in urban core of many big cities fall into this category.In many cases, property owners complain that unreasonably high purity levels are demanded in remediation programs.
Hazardous Waste Management OptionsProduce Less WasteAvoid creating wastes in the first placeRecycle and ReuseConvert to Less Hazardous SubstancesPhysical Treatment (Isolation)Incineration Chemical Processing (Transformation)Bioremediation (Microorganisms)
Hazardous Waste Management Options ContdStore PermanentlyRetrievable StorageCan be inspected and periodically retrieved.Secure LandfillsModern, complex landfills with multiple liners and other impervious layers and monitoring systems.
Summary:Solid WasteWaste Disposal MethodsShrinking the Waste StreamRecyclingHazardous and Toxic WastesFederal LegislationRCRACERCLAManagement Options