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Chapter 19.2 A History of Mismanagement worsening pollution (both chemical and sewage) through the 1950s and 1960s increased recognition of adverse health.

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Presentation on theme: "Chapter 19.2 A History of Mismanagement worsening pollution (both chemical and sewage) through the 1950s and 1960s increased recognition of adverse health."— Presentation transcript:

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2 Chapter 19.2 A History of Mismanagement worsening pollution (both chemical and sewage) through the 1950s and 1960s increased recognition of adverse health effects graphic example was fire on the Cuyahoga River which flows through Cleveland led to passage of Clean Air Act (1970) and Clean Water Act (1972) created dilemma-- if companies can’t vent waste into the atmosphere or flush into waterways, what should they do with it?

3 methods of land disposal in the early 1970s, there were three primary land-disposal methods: 1. deep-well injection 2. surface impoundment 3. landfills with use of safeguards, each of these methods has merits and each is still widely used for hazardous waste disposal

4 deep-well injection involves drilling a hole thousands of feet below groundwater into a porous geological formation or brine well consists of concentric pipes and casings that isolate the wastes as they are injected over time, the wastes will often undergo reactions with naturally occurring materials that make them less hazardous method is currently used for VOCs, pesticides, fuels, and explosives use has declined, but is better than most other methods for keeping toxic wastes from contaminating the hydrologic cycle and the food web

5 Resource Conservation and Recovery Act (1996) amendment in Act led EPA to conduct a study of surface impoundments ~18,000 surface impoundments in use at 7500 facilities at least 2/3 contained hazardous chemicals with carcinogenic and other human health concerns most impoundments were only a few meters above groundwater (more than ½ did not have adequate liners) more than 20 million people lived within 2 km of an impoundment 10% were located within 500 feet of drinking water wells

6 landfills RCRA sets rigid standards for the disposal of hazardous waste to landfills when hazardous wastes are in a concentrated liquid or solid form, they are commonly put into drums, then treated according to their chemical and physical characteristics treatment standards for waste are established by the EPA and characterized as best- demonstrated available technologies (BDATs) standards apply to all solid and liquid hazardous wastes and are used to reduce toxicity

7 midnight dumping and orphan sites with new waste disposal regulations came disreputable operators some would pocket disposal fee then unload wastes in any available location (abandoned warehouse, vacant lots, municipal landfills) other businesses skipped the hassle of waste disposal altogether and stored the materials on their own property when the company went out of business, the waste remained, leading to the name orphan site

8 scope of mismanagement problem of unregulated land disposal of hazardous waste came to the public’s attention thanks to an episode at Love Canal, near Niagara Falls, NY case ended in President Carter signing an emergency declaration in 1978 to relocate hundreds of residents Love Canal led government and independent researchers to begin surveying the extent of the problem around the country bad disposal practices were rampant cases of private well contamination often came to light after people experienced “unexplainable” illnesses over long periods of time

9 Chapter 19.3 Cleaning Up the Mess ensuring safe drinking water Congress passed the Safe Drinking Water Act (1974) to protect the public from the risk of toxic chemicals contaminating drinking water supplies EPA sets national standards to protect public health, including allowable levels of certain contaminants state and public water agencies are required to monitor drinking water to be sure that it meets the standards

10 groundwater remediation used when dumps, leaking storage tanks, or spills of toxic materials have contaminated groundwater to the point of threatening drinking water techniques involve drilling wells, pumping out the contaminated groundwater, purifying it, and reinjecting the purified water back into the ground or discharging it into surface water

11 Superfund for toxic sites our generation faces monumental task of cleaning up thousands of toxic sites resulting from years of mismanaged disposal of toxic materials Congress passed Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in 1980; known commonly as Superfund tax on chemical raw materials provides trust fund for identification of abandoned chemical waste sites, protection of groundwater near the site, remediation of groundwater if it has been contaminated, and cleanup of the site annual appropriations have continually decreased and since 2005, Congress has not renewed the tax

12 how Superfund works: setting priorities (resources are insufficient to clean up all sites at once) as sites are identified, their current and potential threat to groundwater supplies are assessed if a threat to human health exists, most expedient measures are taken immediately to protect the public may include digging deep trench, installing a concrete dike, or capping with impervious layers of plastic to isolate wastes worst sites are put on National Priorities List and scheduled for total cleanup site is reevaluated to determine most cost-effective method for cleanup cleanup begins with efforts to identify potential responsible parties

13 how Superfund works: technology biggest problem at many sites is soil contaminated by leakage one cleanup procedure involves excavating the soil and running it through an incinerator or kiln to burn off chemicals another method is to drill a ring of injection wells around the site and a suction well in the center water containing a harmless detergent is injected, then drawn into the suction well, cleansing the soil along the way withdrawn water is then treated to remove the pollutants and is then reused for injection bioremediation in this process, oxygen and organisms are injected into contaminated zones to breakdown biodegradable toxic organic compounds organisms feed on pollutants, then die when the pollutants are gone

14 evaluating Superfund 11,300 sites remain on the Superfund list (13% of these are “federal facilities”…mostly military bases) as of 2006, 1244 sites were still on the NPL since CERCLA went into effect, 975 sites have received all necessary clean-up construction and 309 sites have been deleted from the list average clean-up takes 12 years and $20 million CERCLA is based on principle that “polluter pays” 70% of clean-up costs have been paid by polluters critics of the program claim that industries are unfairly blamed for pollution that occurred before CERCLA went into effect

15 brownfields defined as “abandoned, idled, or underused industrial and commercial facilities where expansion or redevelopment is complicated by real or perceived environmental contamination” Brownfield Act (2002) provides grants for the assessment of sites and remediation work many brownfield sites lie in economically disadvantaged communities rehabilitation contributes jobs and trades an unsightly blight in a neighborhood for a new, functional facility

16 leaking underground storage tanks one consequence of automobile-based society is millions of underground fuel storage tanks placing tanks underground minimizes risk of explosions and fires, but also hides leaks underground storage tank regulations (part of RCRA) now require strict monitoring of fuel supplies so that leaks can be detected early rules now require all new tanks to have interior lining and cathodic protection (prevents electrolytic corrosion)

17 Chapter 19.4 Managing Current Hazardous Wastes Clean Water Act requires any firm discharging more than a certain volume of waste into natural waterways to have a discharge permit Resource Conservation and Recovery Act are designed to prevent unsafe or illegal disposal of all solid wastes on land three main features: 1. requires that all disposal facilities, such as landfills, have a permit 2. requires that toxic wastes destined for landfills be pretreated to convert them to forms that will not leach 3. requires “cradle-to-grave” tracking of all hazardous waste

18 reduction of accidents and accidental exposures risks to personal and public health lie in exposures that occur as a result of leaks, accidents, and misguided uses of hazardous chemicals regulations: Department of Transportation regulations specifies containers and methods of packing requires placards identifying hazards on trucks and train cars Occupational Safety and Health Act (OSHA) amendments make up “workers right to know” this information often takes the form of material safety data sheets

19 reduction of accidents and accidental exposures regulations (cont.): Superfund Amendments and Reauthorization Act (SARA), Title III passed in response to Bhopal disaster in 1984 accident at Union Carbide plant in Bhopal, India exposed over 600,000 people to deadly fumes official death toll of 10,500, with at least 50,000 other individuals who suffered degrees of visual impairment, respiratory problems, or other injuries investigation revealed that plant officials had scaled back safety and alarm systems to cut costs most deaths and injuries could have been prevented if peopled had known that methyl isocyanite was soluble in water

20 reduction of accidents and accidental exposures regulations (cont.): better known as Emergency Planning and Community Right- to-Know Act requires companies that handle more than 5 tons of any hazardous material to provide “complete accounting” of storage sites, etc. information goes to local emergency planning committee, which is made up of local fire, police, hospital, and other community officials task of committee is to draw up scenarios for accidents involving the chemicals on site and to have a contingency plan for every case

21 reduction of accidents and accidental exposures regulations (cont.): Toxic Substances Control Act requires that manufacturers submit a “pre-manufacturing notice” to the EPA before manufacturing a new chemical in bulk notice includes potential environmental and human health impacts of substance REACH (Registration, Evaluation, and Authorization of Chemicals) policy of European Union regulation will conduct process of screening 30,000 chemical substances for toxicity approach is based on precautionary principle

22 Chapter 19.5 Broader Issues environmental justice and hazardous waste largest commercial hazardous waste landfill in U.S. is located in Emelle, Alabama African-Americans make up 90% of population Choctaw reservation in Philadelphia, Mississippi was targeted to become the home of a 466 acre hazardous waste landfill 870,000 U.S. federally subsidized housing units are within a mile of factories that report toxic emissions to the EPA pollution prevention for a sustainable society pollution control vs. pollution prevention

23 three strategies for pollution prevention 1. minimization or elimination 2. substitution 3. reuse

24 Michigan has 73 sites; only New Jersey (107), Pennsylvania (101), California (90), and New York (78) have more.

25 Five possible ways of managing hazardous waste… 1. PRODUCE LESS --best option --manufacturing methods can be redesigned to produce less waste or none at all --Ex. plastic beads for “sandblasting” metal parts, replacing toxic chemicals

26 2. REUSE --second best option --in the U.S., many programs have been set up to help get industries in touch with other companies that can use the materials that they normally throw away --Ex. company that can only use cleaning solvent once can pass it on to another company is product is not harmed by small amounts of contamination

27 Five possible ways of managing hazardous waste… 3. CONVERSION INTO NONHAZARDOUS SUBSTANCES --some types of waste can be treated chemically to make them less hazardous --Ex. add lime (base) to acids to neutralize them --Ex. some wastes can be treated biologically (add soil bacteria to oil)

28 Five possible ways of managing hazardous waste… 4. INCINERATION --if properly designed and maintained, incinerators can be a safe means of waste disposal --problems: expensive; require pollution-control devices and careful monitoring; not all wastes are burnable

29 Five possible ways of managing hazardous waste… 5. LAND DISPOSAL --most common method in the U.S --deep-well injection = wastes are pumped deep into the ground, where they are absorbed into a dry layer of rock below the level of groundwater --surface impoundment = basically a pond with a sealed bottom (wastes settle to bottom, while water evaporates from the top)


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