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SOLID AND HAZARDOUS WASTE - Moore 2
Objectives for this Chapter
• A student reading this chapter will be able to:– 1. Discuss and explain the consequences of
improper solid waste disposal.– 2. List and characterize the typical municipal
waste stream. – 3. Describe and discuss the methods of
reducing the solid waste stream through reuse and recycling efforts.
SOLID AND HAZARDOUS WASTE - Moore 3
Objectives for this Chapter
• A student reading this chapter will be able to:– 4. Describe the methods of collection and
disposal of municipal solid wastes including the benefits and problems associated with landfills and incinerators.
– 5. Differentiate the types of hazardous waste, and discuss reasons for proper disposal, giving some case examples.
SOLID AND HAZARDOUS WASTE - Moore 4
Objectives for this Chapter
• A student reading this chapter will be able to: – 6. List and describe the various methods of
hazardous waste control emphasizing waste reduction, volume or hazard reduction, and long-term storage and disposal options.
SOLID AND HAZARDOUS WASTE - Moore 5
Objectives for this Chapter
• A student reading this chapter will be able to:– 7. Discuss the positive and negative aspects of
clean-up efforts under “Superfund” and some of the major concerns regarding its future operation.
SOLID AND HAZARDOUS WASTE - Moore 6
SOLID & HAZARDOUS WASTE
• INTRODUCTION– Cities have historically been centers for filth
and disease, and many have degraded because of overpopulation.
• Trash on the Yangtze river in China• Nairobi “The Stinking City in the Sun”• Western Europe up until the 19th Century
SOLID AND HAZARDOUS WASTE - Moore 8
Solid and Hazardous Waste
• Much of the world continues to inappropriately dispose of refuse which: – (1) invites the proliferation of rodents and
insects; – (2) becomes a source of contamination to
groundwater; – (3) pollutes ambient air when combusted;
SOLID AND HAZARDOUS WASTE - Moore 9
Solid and Hazardous Waste• Much of the world
continues to inappropriately dispose of refuse which: – (4) facilitates the
spread of debris around the dumping site;
– (5) lowers property values about the site; and
– (6) encourages the spread of disease from microorganisms and toxic chemicals.
Cambodia dump children
SOLID AND HAZARDOUS WASTE - Moore 10
Solid and Hazardous Waste
– The Resource Conservation and Recovery Act (RCRA) of 1976 forbade open dumping and introduced the concept of the sanitary landfill.
– Land fill siting and “NIMBY”
SOLID AND HAZARDOUS WASTE - Moore 11
Solid and Hazardous Waste
• The USEPA endorsed several different practices to Reduce Municipal Solid Waste (MSW) that include: – (1) source reduction (including reuse of products and
backyard composting of yard trimmings);– (2) recycling of materials (including composting); and– (3) waste combustion (preferably with energy recovery)
and landfilling.
SOLID AND HAZARDOUS WASTE - Moore 12
DEFINITION AND CHARACTERIZATION OF MSW
• Definition of MSW– Materials in MSW include paper and
paperboard, yard trimmings, food wastes, plastics, glass, metal, and wood wastes.
– Examples of the types of MSW in each of these categories is listed in Table 11-1.
SOLID AND HAZARDOUS WASTE - Moore 14
Characterization of MSW
– MSW does not include everything that is landfilled in Subtitle D landfills (RCRA Subtitle D), but excludes municipal sludge, industrial non-hazardous waste, construction and demolition waste, agricultural waste, oil and gas waste, and mining wastes (Fig 11-1).
SOLID AND HAZARDOUS WASTE - Moore 16
Characterization of MSW
– The total amount of MSW materials generated(thousands of tons) from 1960 to 1996 are shown in Figure 11-2.
SOLID AND HAZARDOUS WASTE - Moore 18
Characterization of MSW
– Paper and paperboard materials represented the largest component at 13 percent, followed by food wastes (10.4%), and plastics (9.4%) (Fig. 11-3).
– The amount of MSW generated in 1996 and categorized as products is shown as Figure 11-4.
SOLID AND HAZARDOUS WASTE - Moore 21
COLLECTION AND DISPOSAL OF SOLID WASTE
• Collection of MSW– The removal of solid waste is the responsibility
of government which must develop and enforce regulations that protect the public health by proper collection and disposal of municipal waste.
SOLID AND HAZARDOUS WASTE - Moore 22
Collection of MSW
– Collection vehicles often include manually loaded compacting bodies which increases the weight (capacity) of the load that can be carried, and facilitates emptying at the disposal site (Fig 11-5, 6).
SOLID AND HAZARDOUS WASTE - Moore 25
Collection of MSW
• A transfer station is a site where solid waste is concentrated before taken to a processing facility or a sanitary landfill (Fig. 11-7).
SOLID AND HAZARDOUS WASTE - Moore 27
Collection of MSW
• The concentration most often involves compaction by placing the waste into a metal channel where a ram compresses the waste into a roll-off collection container (Fig. 11-8).
SOLID AND HAZARDOUS WASTE - Moore 29
Collection of MSW
• Some transfer stations also feature recycling bins where separated items such as metal cans, plastic milk bottles (HDPE), paper and cardboard, and glass containers may be collected and periodically removed for further processing and resale (Fig 11-9).
SOLID AND HAZARDOUS WASTE - Moore 31
Management of MSW
• Nationally, more than half (55 percent) of the total MSW collected is landfilled about 27.3 percent is recovered for recycling (or composted) and 17.2 percent is combusted with most combustion systems employing energy recovery (Fig. 11-10).
SOLID AND HAZARDOUS WASTE - Moore 33
Management of MSW
• Landfill Design– Historically landfills have been sources of
pollution, producers of methane gas and odors, and breeding sites for pests.
– The standards for landfill construction mandated under RCRA Subtitle D should prevent the above problems (Fig. 11-11).
SOLID AND HAZARDOUS WASTE - Moore 35
Management of MSW
• Landfill Design– The bottom liners may be composed of one or
more layers of clay or a synthetic flexible membrane(s) (or some combination of both) (Fig. 11-12).
SOLID AND HAZARDOUS WASTE - Moore 37
Landfills are not secure
• Landfill caps or covers are meant to be impermeable but can be disturbed by:– burrowing and soil-dwelling animals; roots of
vegetation;– precipitation; freeze-thaw cycles; wind;– uneven settling; migration of chemicals of
objects;– exposure to sunlight.
SOLID AND HAZARDOUS WASTE - Moore 38
Landfills are not secure
– There are less than 2,400 municipal solid waste landfills today although the total landfill capacity has not declined considerably.
– The Northeast United States has the fewest landfills (208) and the fewest remaining years of landfill capacity (Fig. 11-13).
SOLID AND HAZARDOUS WASTE - Moore 39
Fig. 11-13
Number of landfills by region Typical landfill operation
SOLID AND HAZARDOUS WASTE - Moore 40
Source Reduction
• Activities that reduce the amount of the toxicity of wastes prior to entering the waste stream are referred to as source reduction.– Products package reuse– Package or product redesign that reduces material
or toxicity– Reducing use by modifying practices (Fig. 11-14)
SOLID AND HAZARDOUS WASTE - Moore 42
Recovery for Recycling (Including Composting)
– The act of removing materials from MSW for a productive use is referred to as recycling or resource recovery.
SOLID AND HAZARDOUS WASTE - Moore 43
Recovery for Recycling (Including Composting)
• Recycling is perceived to: – (1) conserve resources by reducing the need for
virgin and nonrenewable materials; – (2) reduce the amount of pollution by using
secondary materials that require less energy to process; and
– (3) save energy by using recycled materials, since less is required for processing.
SOLID AND HAZARDOUS WASTE - Moore 44
Recovery for Recycling (Including Composting)
– The Northeast serves more than 43 million people or over 80 percent of its population with a curbside recyclables program (Fig. 11-15).
SOLID AND HAZARDOUS WASTE - Moore 46
Recovery for Recycling (Including Composting)
– Materials recycling facilities (MRFs) prepare recyclables for marketing (Fig. 11-16).
– A magnet removes steel objects and recyclables are separated manually (Fig. 11-17).
SOLID AND HAZARDOUS WASTE - Moore 49
Recovery for Recycling (Including Composting)
– Glass bottles are separated into clear, brown, and green glass, and ground into small smooth pellets called cullet.
– An example of green glass cullet is shown in Fig. 11-18.
SOLID AND HAZARDOUS WASTE - Moore 51
Trends in Resource Recovery
– Recovery rates increased significantly from the mid-1980s to the present national level of over 27 percent (Fig. 11-19).
SOLID AND HAZARDOUS WASTE - Moore 53
Trends in Resource Recovery
– Most of the recovery appears to be in paper and paperboard, accounting for nearly 57 percent of the material recovered.
– This is followed by yard trimmings and food wastes which are composted (19.7 percent), and metals at 11.1 percent (Fig. 11-20).
SOLID AND HAZARDOUS WASTE - Moore 55
Composting
– Composting is a controlled process of degrading organic matter by microorganisms into a humus-like material.
– The composted material is often low in plant nutrients but is useful for conditioning soil by improving soil porosity and aeration, and increasing water retention.
SOLID AND HAZARDOUS WASTE - Moore 56
Composting
– In some sophisticated operations, the entire process from shredding to aeration, curing, and finishing are performed in an in-vessel composting system (Fig. 11-21a, b).
SOLID AND HAZARDOUS WASTE - Moore 59
Composting
• Most composting uses a windrow process in which rows of material are placed next to each other outdoors and periodically mixed to incorporate air into the mix (Fig. 11-22).
SOLID AND HAZARDOUS WASTE - Moore 61
Compost
• Compost is being used for wetlands mitigation, land reclamation, storm filtrates, soil amendments, mulches, and low-grade fertilizers.
• The market penetration of compost is likely to increase when combined with education on the benefits of compost use (Fig. 11-23).
SOLID AND HAZARDOUS WASTE - Moore 63
Combustion
• MSW can also be treated by combustion– Generally, combustion with the production of
energy is called waste-to-energy (WTE), while combustion of MSW without energy recovery is called incineration.
SOLID AND HAZARDOUS WASTE - Moore 64
Combustion
• WTE plants are generally mass burn, although many incorporate recycling activities that remove noncombustible items such as metals and glass prior to burning.
• The facility is designed in stages to minimize emissions (Fig. 11-24).
SOLID AND HAZARDOUS WASTE - Moore 66
HAZARDOUS WASTES
• Background– Love Canal– Times Beach, MO.– Woburn, MA.– Environmental Justice
SOLID AND HAZARDOUS WASTE - Moore 67
What is Hazardous Waste?
• The Resource Conservation and Recovery Act (RCRA) of 1976.– The definition of hazardous waste in RCRA
includes any discarded material that may pose a substantial threat or potential danger to human health or the environment when improperly handled.
SOLID AND HAZARDOUS WASTE - Moore 68
RCRA
• This process is called the “cradle-to-grave” system and is meant to protect public health by: – (1) defining what wastes are hazardous; – (2) tracking wastes to the point of disposal; – (3) assuring that treatment, storage, and
disposal (TSD) facilities meet minimum national standards;
SOLID AND HAZARDOUS WASTE - Moore 69
RCRA
• This process is called the “cradle-to-grave” system and is meant to protect public health by: – (4) and making certain TSDs are properly
maintained after closure, and that facility owner/operators are financially responsible for hazardous waste releases that may occur at their facility.
SOLID AND HAZARDOUS WASTE - Moore 70
Hazardous Waste Regulations
• Amendments were made to RCRA in 1984 that significantly expanded its regulatory powers.
• The amendments are known as the Hazardous and Solid Waste Amendments (HSWA).
SOLID AND HAZARDOUS WASTE - Moore 71
The Hazardous and Solid Waste Amendments (HSWA)
• The HSWA focuses on protecting groundwater by:– (1) restricting the treatment, storage, and
disposal of hazardous wastes in land management facilities;
– (2) mandating stricter requirements for landfills accepting hazardous waste;
SOLID AND HAZARDOUS WASTE - Moore 72
The Hazardous and Solid Waste Amendments (HSWA)
• The HSWA focuses on protecting groundwater by:– (3) requiring a schedule for determining if the
landfilling of untreated hazardous waste should be phased out;
– (4) increasing the numbers of people who fall under RCRA regulations by including small quantity generators; and
SOLID AND HAZARDOUS WASTE - Moore 73
The Hazardous and Solid Waste Amendments (HSWA)
• The HSWA focuses on protecting groundwater by:– (5) creating a new program for the detection,
control, and management of hazardous liquids (primarily petroleum) in underground storage tanks.
SOLID AND HAZARDOUS WASTE - Moore 74
Hazardous Waste Regulations
• Other efforts to control hazardous waste are:– The Pollution Prevention Act of 1990– Waste Minimization National Plan
SOLID AND HAZARDOUS WASTE - Moore 75
The Management of Hazardous Wastes
• The three major options for managing hazardous waste include: – (1) reducing the production of waste by
reducing the amount generated or recycling/reusing the hazardous material after its generation;
SOLID AND HAZARDOUS WASTE - Moore 76
The Management of Hazardous Wastes
• The three major options for managing hazardous waste include: – (2) reducing the volume and/or hazard off the
waste; and – (3) long-term storage or disposal (Fig. 11-25).
SOLID AND HAZARDOUS WASTE - Moore 78
Reduction of Generation of Hazardous Waste
• The generation of hazardous waste can be minimized by: – (1) eliminating or substituting raw materials for
less hazardous ones; – (2) changing the manufacturing process to
reduce or eliminate hazardous waste; and – (3) separating or segregating waste at the
source to prevent the contamination of non-hazardous waste.
SOLID AND HAZARDOUS WASTE - Moore 79
Technologies for Hazardous Waste Treatment
• Biological• Chemical• Physical• Solidification/Stabilization• Thermal Treatment
SOLID AND HAZARDOUS WASTE - Moore 80
Hazardous Waste Disposal
• Landfills • Deep-well Injection • Surface Impoundments• Figure 11-26
SOLID AND HAZARDOUS WASTE - Moore 82
Cleaning Up
• Before the 1980s, it was common practice for industries and municipalities to haul the wastes to a depression in the ground, dump them, and cover them over.
• In many cases, drums of toxic wastes were simply stored in piles on-site (Fig. 11-27).
SOLID AND HAZARDOUS WASTE - Moore 84
Cleaning Up
• In December of 1980, congress passed the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). – This Act, also known as “Superfund”,
authorized the federal government to spend $1.6 billion over a five year period for emergency clean-up activities.
SOLID AND HAZARDOUS WASTE - Moore 85
CERCLA
– The term “Superfund” is attributed to the fact that the bill created a trust fund financed primarily by excise taxes on chemicals and oil, and an environment tax on corporations.
SOLID AND HAZARDOUS WASTE - Moore 86
CERCLA
– The USEPA identifies Potentially Responsible Parties (PRPs).
– The liability rules applied include: retroactive liability, joint and several liability, and strict liability (Fig. 11-28).
SOLID AND HAZARDOUS WASTE - Moore 88
Superfund
• The USEPA established a hazard-ranking system (HRS) based on the estimated hazard potential of the hazardous waste site.
• The factors used to make this estimate include the waste characteristics; the distance to the local population, surface water, groundwater, and drinking water supplies.
SOLID AND HAZARDOUS WASTE - Moore 89
Superfund
• Environmental groups and concerned citizens charged that RCRA was not being vigorously enforced.
• Congress responded by passing the Superfund Amendments and Reauthorization Act of 1986 (SARA), which increased the program’s funding and provided new and stricter standards.
SOLID AND HAZARDOUS WASTE - Moore 90
Superfund
• There are nearly 33,000 hazardous waste sites that have come under Superfund authority.
• More than 1300 of these sites are on the USEPA’s National Priority List (NPL).
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Superfund
• In 1997, nearly 500 of the 1,405 sites listed were in the stage of construction completion with nearly 55 sites where remedial assessment had not yet started (Fig. 11-29).