2 Early Concepts of Water Disposal During the Industrial Revolution the volume of waste produced in the U.S. was relatively small and managed through “dilute and disperse”Factories were located near rivers for easy transport of materials by boat, sufficient water for processing and cooling, and easy disposal of waste in to the river.As urban areas expanded the concept of “concentrate and contain” was adopted
3 Problems with waste management: Containment is not always achieved because containers may leak or break and allow waste to escapeIt has been estimated that within the next few years approximately half the cities in the U.S. may run out of landfill spaceA decade ago the cost of disposal of 1 metric of urban refuse was approximately $5-$10Today the cost is about $32Disposal and treatment of liquid and solid waste costs about $20 billion per year
4 Modern TrendsThe environmentally correct concept with respect to waste management is to consider wastes as resources out of placeZero waste movement: waste wouldn’t exist because it would not be produced or if produced it would be a resource to be used again
5 Industrial ecology: the study of relationships among industrial systems and their links to natural systemsWaste from one part of the system would be a resource for another part.
6 Zero Waste ProductionCanberra, Australia and the Netherlands are both working towards the final goal of having zero waste.Much of the waste has already been removed from these areas by the implementation of pollution taxes.House hold level: the government is considering programs like “pay as you throw” that charges people by the volume of waste they produce.
7 Example of Industrial Ecology Many waste management programs involve moving waste from one site to another and not really managing it.Waste may be placed in landfills which produces methane gas, but if managed properly, the methane can be used as a resource and burned as fuel
8 Integrated Waste Management Defined as a set of management alternatives that includes reuse, source reduction, recycling, composting, landfill, and incinerationReduce, Reuse, and Recycle: ultimate objective is to reduce the amount of urban and other waste that is disposed of in landfills, incinerators, and other waste management facilitiesStudy of waste stream (waste produced) and areas that utilize IWM shows that disposed waste can be reduced by at least 50%, if not 70%Recycling is a huge factor in the reduction of the urban waste stream
9 Recycling Public support is key There has been an increase in the willingness of industry and business to support recyclingLess packaging for productsOn-site bins for recyclingInexpensive canvas shopping bags instead of plastic and paper bagsMore easily disassembled products that can be recycledConsumers are more likely to purchase products that can be recycled or containers that are more easily recycled or compostedMarkets and processing facilities must be developed to ensure that recycling is a sound financial venture
10 Recycling of Human Waste Use of human waste or “night soil” on crop lands is an ancient practiceLong history in Asia where Chinese agriculture was sustained for thousands of years through collection of human waste which was spread over agricultural fieldsThe practice spread and became one of the primary methods of disposal in many areasOccasionally spread infectious diseasesMajor problem with this practice is that thousands of chemicals and metals flow through our modern waste stream and can be toxic
11 Recycling of Human Waste Goals should be that sewage sludge contains no toxic materials at allThe problem is that the sewer lines from urban homes are the same ones used by industry so it is unlikely to produce a form of sludge that is safe for us and other living thingsSolutions:Separate urban waste from industrial wastePretreat waste from industrial sources to remove hazardous components before they enter the wastewater stream
12 Materials ManagementDefinition: To use more sustainable use of materials combines with resource conservation.Recycling, a type of Materials Management, has generated tens of thousands of jobs in the US and reduced the amount of urban waste sent from homes to landfills from 90% to 65% today.
13 Ways of Materials Management Eliminate subsidies for extraction of virgin materials such as minerals, oil, timber.;Establish “green building” incentives that encourage the use of recycled-content materials and products in new construction.Assess financial penalties for production that uses negative materials management practices.Increase the number of jobs in the new technology of reuse and recycling of resources.Provide financial incentives for industrial practices and products that benefit the environment by enhancing sustainability.
14 Great leaps in Management 50% of steel is now produced from scrap so many new steel mills have been made for the sole reason of using scrap.Similarly, new paper mills are constructed to use recycled paper near cities unlike their counterparts near forested areas.
15 Solid-Waste Management Solid-waste management continues to be a problem in not only the United States but world wide.Waste is being irresponsibly and poorly handled, which can cause pollution of the soil and waterPeople also illegally dump which has many implications on the environment.The keys to stopping illegal dumping prevention has been awareness, through educational programs.
16 Composition and Methods of Removal Composting: A biochemical process in which organic materials (like kitchen scraps and law clippings) decompose to a rich soil like material. It is popular in Asia and Europe, but a major drawback is the necessity to separate organic material from other waste.Incineration: A process that burns combustible waste (at 1, degrees Fahrenheit) to only ashes. Under Ideal conditions it could reduce waste volume by 75%-95%, but due to maintenance and water supply problems, it is only 50%. Although effective, Incinerating produces many toxins, which can lead to acid rain. They are also vey expensive to build and maintain.
17 Open Dumps Sanitary Landfills In the past, solid waste was disposed in open dumps-waste was piled up without being covered or protectedOpen dumps have been located wherever land is available without regard to safety, health or aesthetic degradationIn the U.S. thousands of open dumps have been closed and new open dumps are banned.Designed to concentrate and contain refuse without creating a nuisance or hazard to public health or safetyWaste is confined to the smallest practical area, reduced to the smallest volume and covered with soil everyday
18 LeachateThe most significant hazard from a sanitary landfill is pollution of groundwater or surface water.Leachate: noxious, mineralized liquid capable of transporting bacterial pollutantsIf waste buried in land fills comes into contact with water, leachate is producedThe nature and strength of the leachate depends on the makeup of the waste, the amount of water, and the amount of time the water is in contact with the refuse
19 Monitoring Pollution in Sanitary Landfills Once a site is chosen for a sanitary landfill, monitoring the movement of groundwater should begin.Monitoring is accomplished by periodically taking samples of water and gas from monitoring wells
20 How Pollutants Can Enter the Environment from Sanitary Landfills Methane, ammonia, hydrogen sulfide, and nitrogen can be produced from compounds in the soil and the waste and can enter the atmosphere.Heavy metals(lead, iron) can be retained in the soilSoluble materials(chloride, nitrate, sulfate) can readily pass through the waste and soil to the groundwater system.Overland runoff can pick up leachate and transport it into streams and rivers.Some plants growing near the site may take up heavy metals, which may then pass up the food chain and reach animals.If plant residue from crops contain toxic substances, these substance return to the soil.Streams, and rivers may become contaminated by waste from groundwater seeping into the channel or by surface runoff.Toxic materials can be transported to other areas by wind.
21 How Pollutants Can Enter the Environment from Sanitary Landfills Modern sanitary landfills are engineered to include multiple barriers:-Clay and plastic liners to limit the movement of leachate-Surface and subsurface drainage to collect leachate-Systems to collect methane gas-Groundwater monitoring detect leaks
22 Federal Legislation for Sanitary Landfills Resource Conservation and Recovery Act of 1980:intended to strengthen and standardize design, operation, and monitoring of sanitary landfillsStates must choose two options:1.Comply with federal standards.Landfills may not be sited on floodplains, wetlands, earthquake zones, unstable land, or near airportsLandfills must have linersLandfills must have a leachate collection systemLandfill operators must monitor groundwater for many specified toxic chemicalsLandfill operators must meet financial assurance criteria to ensure that monitoring continues for 30 years after closure2.Seek EPA approval of solid-waste management plans.Groundwater monitoring may be suspended if the landfill operator can demonstrate that hazardous materials are not migrating from the landfillAlternative types of daily cover over the wasteAlternative groundwater protection standard are allowed.Alternative schedules for documentation of groundwater monitoring are allowedUnder certain circumstances, landfills in wetlands and fault zones are allowedAlternative financial assurance mechanisms are allowed