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2. Hazardous and Toxic Materials. Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment. At sites around the world, accidental or purposeful releases of hazardous and toxic chemicals are contaminating the land, air and water.In
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1. 1 Regulating Hazardous Materials Chapter 19
2. 2 Hazardous and Toxic Materials Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment.
At sites around the world, accidental or purposeful releases of hazardous and toxic chemicals are contaminating the land, air and water.
Increasingly, governments and international agencies are attempting to control the growing problem.
Heavy metal (lead, mercury, copper, etc.)
Benezene Dioxin
Fuel additives PCB
Cleaning fluids Pesticides/herbicides
Asbestos DDT
3. 3 Life Cycle of Toxic Substances
4. 4 Hazardous and Toxic - Some Definitions Hazardous - EPA defines hazardous materials as having one or more of the following characteristics:
Ignitability (Fire hazard)
Corrosiveness (Corrodes material)
Reactivity (Unstable)
Toxicity (May release toxins)
Some hazardous materials fall into several categories.
5. 5 Hazardous and Toxic - Some Definitions Terms are incorrectly used interchangeably.
Toxic - Commonly refers to a narrow group of substances that cause human injury or death.
Hazardous - Broader term; refers to all dangerous materials that create a human health, or environmental problem.
By-products of industrial, business, or household activities for which there is no immediate use.
Must be disposed of in an appropriate manner.
Stringent regulation pertaining to production, storage, and disposal.
6. 6 Definitions Persistent and Non-Persistent Pollutants
Non persistant toxins – break down readily and cause temporary problems (chlorine gas, organophosphates - Raid)
Many toxic organic materials can be destroyed by decomposer organisms.
Do not accumulate in food chain.
Persistent toxins remain in the environment, essentially unchanged, for long periods, and build-up leads to chronic problems.
Most are man-made.
Polychlorinated Biphenyls PCB’s
7. 7 Issues Involved in Setting Regulations Identification of Hazardous & Toxic Materials
List often limited to current offenders and substances already linked to adverse effects.
Asbestos
DDT
8. 8 Issues Involved in Setting Regulations Setting Exposure Limits
Nearly all substances are toxic in sufficient quantities.
People can be exposed in three ways:
Inhalation
Consumption
Absorption
9. 9 Setting Exposure Limits Typically the regulatory agency will determine the level of exposure at which test animals are affected (threshold level) and then set the exposure level longer to allow for a safety margin.
Must account for species-specific thresholds.
10. 10 Issues Involved in Setting Regulations Acute vs. Chronic Toxicity
Effects of massive doses at once (acute toxicity) and small doses over time (chronic toxicity) differ.
Chronic much harder to detect as effects may not surface for long periods of time.
Synergism
Assessing effects of chemical mixtures.
11. 11 What Environmental Problems are Caused by Hazardous Wastes? Hazardous wastes enter the environment in many ways:
Evaporation
Fugitive Emissions
Improper Disposal
Improper Labeling and Record-Keeping
12. 12 Health Risks Associated with Hazardous Wastes 1,000 new chemicals produced eaach year.
70,000 in use.
Industrial chemicals handled and disposed of improperly.
Pose health hazard.
Linking chemicals to specific diseases difficult
No toxicity data.
13. 13 Hazardous Waste Dumps: A Legacy of Abuse Prior to RCRA in 1976, hazardous waste was essentially unregulated.
Hazardous wastes were simply buried or dumped.
Sites typically located convenient to the industry and were often in environmentally sensitive areas.
In North America alone, currently over 25,000 abandoned or uncontrolled sites.
14. 14 U.S. Resource Conservation and Recovery Act (RCRA) 1976 Substances are considered toxic or hazardous if they:
Cause or significantly contribute to an increase in mortality or an increase in serious irreversible, or incapacitating reversible, illness; or pose a substantial present or potential hazard to human health or the environment when properly treated, stored, transported, disposed of, or otherwise managed.
Most toxicity studies done on a single compound.
15. 15 Comprehensive Environmental Response, Compensation and Liability Act CERCLA or “SUPERFUND” (1980)
Develop comprehensive program to set priority list.
Make responsible parties pay for clean-up when possible.
Set up $1.6 billion Hazardous Waste Trust Fund.
Advance scientific and technological capabilities in hazardous waste management, treatment, and disposal.
16. 16 CERCLA National Priority List
Under CERCLA, over 44,000 sites were evaluated, and about 11,000 were considered serious enough to warrant further investigation.
About 1,200 of those sites were placed on National Priority List.
17. 17 CERCLA Because any contributor to the site can be held responsible for entire clean-up costs, many companies find it cost-effective to hire lawyers and fight their inclusion into clean-up costs.
But by 2004, there were about 1,200 sites on the National Priorities list.
About 900 cleaned up.
Most of remaining sites in progress.
$27 billion in total expenditures.
18. 18 Toxic Chemical Releases In 1987, any industrial plant that released at least 23,000 kg of toxic pollutants into the environment was required to file a report.
Primarily manufacturing industries.
Allowed EPA to target specific industries for enforcement action.
19. 19 Toxic Chemical Releases About 2.8 billion kg of toxic chemicals reported released into the environment by industry in 2001.
Primary industries involved are mining, power generation, chemical, and metal manufacturing.
20. 20 Sources of Toxic Releases
21. 21 Hazardous Waste Management Choices In the past, management of hazardous waste was always added on to the end of the industrial process.
In recent years, EPA and other regulatory agencies have emphasized pollution prevention and waste minimization.
22. 22 Pollution-Prevention Hierarchy
23. 23 Reducing Waste at the Source Pollution Prevention
Encourage changes that prevent hazardous wastes from being produced.
U.S. army phasing out lead bullets.
Waste Minimization
Manufacturing changes to reduce waste.
Replace hazardous solvents.
Allow water to evaporate from waste to reduce volume.
24. 24 Recycling Wastes Use wastes for another purpose, thus eliminating them as “waste.”
Burn waste oils and solvents as fuel.
Incorporate ash or other solid wastes into concrete or other building materials. – Illinois Power Plant at Havana…
25. 25 Treating Wastes Reduce amounts of waste or modify hazardous nature.
Neutralization
Biodegradation
Air Stripping
Carbon Absorption
Precipitation
26. 26 Disposal Methods Currently, the two most common methods for disposing of hazardous wastes are incineration and land disposal.
Incineration (Thermal Treatment)
Burn wastes at high temperature. Can destroy 99.9999% of hazardous materials
High costs and concerns about emissions have kept incineration from becoming a major method in North America.
27. 27 Disposal Methods Land Disposal is the primary method used when all other options have been exhausted.
Deep-Well Injection
Discharge or Liquids Into Water Sources
Placement of Liquid Wastes into Surface Holding Areas
Storage of Solid Wastes in Hazardous Waste Landfills
28. 28 Disposal Methods Immobilization puts waste into a solid form that is easier handle, and is less likely to enter the surrounding area.
Fixation
Solidification
29. 29 The Love Canal Story Love Canal is a 16-acre landfill in the southeast corner of the City of Niagara Falls, New York, about 0.3 mile north of the Niagara River.
In the 1890s, a canal was excavated to provide hydroelectric power. Instead, it was later used by Hooker Electrochemical for disposal of over 21,000 tons of various chemical wastes.
Dumping ceased in 1952, and in 1953 the disposal area was covered and deeded to the Niagara Falls Board of Education.
Extensive development occurred near the site, including construction of an elementary school and numerous homes.
Problems with odors and residues, first reported at the site during the 1960s, increased in the 1970s as the water table rose, bringing contaminated ground water to the surface.
77,000 people affected
30. 30 Silent Spring Silent Spring describes how DDT entered the food chain, accumulated in the fatty tissues of animals causing cancer and genetic damage.
A single application on a crop killed insects for weeks and months, and not only the targeted insects but countless more, and remained toxic in the environment even after it was diluted by rainwater.
Carson concluded that DDT and other pesticides had irrevocably harmed birds and animals and had contaminated the entire world food supply.
31. 31 Superfund EPA Site Superfund site
http://www.epa.gov/superfund/
Using “tools” , investigate 5 cities in the US
32. 32