Hazardous wastes


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An overview of the environmental concerns from hazardous materials-includes regulation and disposal.

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Hazardous wastes

  1. 1. Hazardous Waste Special Stuff
  2. 2. Waste Categories
  3. 3. Some things CAN’T go in here: Topsoil Sand Clay Garbage Garbage Sand Synthetic liner Sand Clay Subsoil When landfill is full, layers of soil and clay seal in trash Methane storage and compressor building Electricity generator building Leachate treatment system Methane gas recovery Pipe collect explosive methane gas used as fuel to generate electricity Compacted solid waste Leachate storage tank Leachate monitoring well Groundwater monitoring well Leachate pipes Leachate pumped up to storage tanks for safe disposal Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Probes to detect methane leaks Groundwater
  4. 4. What can and can’t go in CharMeck new green bins… http://charmeck.org/city/charlotte/SWS/CurbIt/Recycling/Pages/Home.aspx
  5. 5. Largest Source of UN regulated Hazardous Wastes What Harmful Chemicals Are In Your Home? Cleaning • Disinfectants • Drain, toilet, and window cleaners • Spot removers • Septic tank cleaners Paint • Latex and oil-based paints • Paint thinners, solvents, and strippers • Stains, varnishes, and lacquers • Wood preservatives • Artist paints and inks General • Dry-cell batteries (mercury and cadmium) • Glues and cements Gardening • Pesticides • Weed killers • Ant and rodent killers • Flea powders Automotive • Gasoline • Used motor oil • Antifreeze • Battery acid • Solvents • Brake and transmission fluid • Rust inhibitor and rust remover
  6. 6. What Can You Do at Home? What Can You Do? Hazardous Waste <ul><li>Use pesticides in the smallest amount possible. </li></ul><ul><li>Use less harmful substances instead of commercial chemicals for most household cleaners. For example, use liquid ammonia to clean appliances and windows; vinegar to polish metals, clean surfaces, and remove stains and mildew; baking soda to clean household utensils, deodorize, and remove stains; borax to remove stains and mildew. </li></ul><ul><li>Do not dispose of pesticides, paints, solvents, oil, antifreeze, or other products containing hazardous chemicals by flushing them down the toilet, pouring them down the drain, burying them, throwing them into the garbage, or dumping them down storm drains. </li></ul>Reduce Dispose Of Properly Refuse to use Toxins
  7. 7. New Threat: E-Waste Main concern heavy metals… Lead Mercury Cadmium Arsenic Chromium
  8. 8. Recent Study in China Journal of Environmental Science and Health, Part A, Volume 45, Issue 7 June 2010 , pages 824 - 835
  9. 9. Mercury (Hg) <ul><li>Released into the atmosphere from burning coal (#1) , waste incineration , ore smelting. Released in landfills from breakdown of ewaste (leachate). </li></ul><ul><li>Converts into toxic inorganic Hg 2+ forms and methylmercury (CH 3 Hg + ) </li></ul><ul><li>Attacks nervous systems and brains of children </li></ul><ul><li>Bioaccumulates/biomagnifies in fish </li></ul><ul><ul><li>Fish advisories in place for many US waterways </li></ul></ul>
  10. 10. Mercury Poisoning Solutions Mercury Pollution Prevention Control Sharply reduce mercury emissions from coal burning plants and incinerators Tax each unit of mercury emitted by coal-burning plants and incinerators Collect and recycle mercury containing electric switches, relays, and dry-cell batteries Require labels on all products containing mercury Phase out waste incineration Remove mercury from coal before it is burned Convert coal to liquid or gaseous fuel Switch from coal to natural gas and renewable energy resources such as wind, solar cells, and hydrogen Phase out use of mercury in all products unless they are recycled
  11. 11. Lead (Pb) <ul><li>Potent neurotoxin </li></ul><ul><li>Banned in US gasoline (1976 with phase out by 1986) </li></ul><ul><li>Banned lead-based paints (1970-1978) </li></ul><ul><li>Especially harmful to children-still unsafe levels in the blood of many children </li></ul><ul><li>Lead still in paint and pipes of older buildings </li></ul><ul><li>Plumbing may still contain lead (used to solder pipes) </li></ul><ul><li>Found in cathode ray tubes of old TVs and computer screens (ewaste) and lead-acid car batteries (thus, a landfill issue) </li></ul><ul><li>Can be released into the atmosphere during incineration </li></ul>
  12. 12. Lead Poisoning Solutions Lead Poisoning Prevention Control Wash fresh fruits and vegetables Sharply reduce lead emissions from old and new incinerators Replace lead pipes and plumbing fixtures containing lead solder Remove leaded paint and lead dust from older houses and apartments Remove lead from TV sets and computer monitors before incineration or land disposal Test for lead in existing ceramicware used to serve food Test existing candles for lead Phase out leaded gasoline worldwide Phase out waste incineration Test blood for lead by age 1 Ban lead solder in plumbing pipes, fixtures, and food cans Ban lead glazing for ceramicware used to serve food Ban candles with lead cores
  13. 13. Characteristics of Hazardous Wastes (meets 1 or more characteristics) <ul><li>Toxic -harmful if ingested or absorbed, carcinogenic, teratogenic, mutagenic </li></ul><ul><ul><li>Ex. solvents, paint strippers, pesticides </li></ul></ul><ul><li>Ignitable -easily flammable </li></ul><ul><ul><li>Ex. Solvents, paint thinner, gasoline, used oil </li></ul></ul><ul><li>Corrosive -strong acids or bases </li></ul><ul><ul><li>Ex. Batteries (dissolve metal containers!) </li></ul></ul><ul><li>Reactive -unstable and can release toxic fumes </li></ul><ul><ul><li>Ex. Chlorine products, explosives </li></ul></ul>*Largest source of hazardous waste is industry*
  14. 14. U.S. Federal Regulations on Hazardous Wastes <ul><li>Resource Conservation and Recovery Act (RCRA) 1976 </li></ul><ul><ul><li>Bans all open dumping of wastes--encouraged source reduction (Rs) </li></ul></ul><ul><ul><li>Also sets standards for non-hazardous solid disposal (landfills) </li></ul></ul><ul><ul><li>Defines hazardous wastes (previous slide) </li></ul></ul><ul><ul><li>Sets standards/regulations for management/disposal </li></ul></ul><ul><ul><li>Permits must be issued to producers who must insure “cradle-to-grave” tracking of waste (only if more than 100 kg/month) </li></ul></ul><ul><ul><li>Thought to only cover about 5% of actual hazardous wastes </li></ul></ul><ul><li>Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or Superfund) 1980 </li></ul><ul><ul><li>Funds cleanup of hazardous waste sites (the “Superfund”) </li></ul></ul><ul><ul><li>Establishes a National Priority List (NPL) for cleanup--1,280 current sites listed (1,100 completed) </li></ul></ul><ul><ul><li>Has shifted from polluter-pays to taxpayer pays (1995) </li></ul></ul>
  15. 15. National Priorities List
  16. 16. Hazardous Waste Priorities Produce Less Waste Manipulate processes to eliminate or reduce production Recycle and reuse Convert (treat) to Less Hazardous or Nonhazardous Substances Incineration Chemical, physical, and biological treatment Put in Perpetual Storage (LAST choice!) Secure Landfill Underground injection Surface impoundments
  17. 17. Hazardous Wastes Strategies <ul><li>Prevention is better than disposal or cleanup (Cradle to Cradle)! </li></ul><ul><li>Bioremediation (with bacteria) /Phytoremediation (with plants) </li></ul><ul><li>Incineration </li></ul><ul><li>Deep-well disposal </li></ul><ul><li>Surface impoundments </li></ul><ul><li>Secure landfills </li></ul>
  18. 18. Phytoremediation Inorganic metal contaminants Organic contaminants Radioactive contaminants Brake fern Poplar tree Indian mustard Oil spill Groundwater Soil Polluted groundwater in Polluted leachate Decontaminated water out Landfill Willow tree Phytoextraction Roots of plants can absorb toxic metals such as lead, arsenic, and others and store them in their leaves. Plants can then be recycled or harvested and incinerated. Phytodegradation Plants can absorb toxic organic chemicals and break them down into less harmful compounds which are stored or released into the air. Phytostabilization Plants can absorb chemicals and keep them from reaching groundwater or nearby surface water. Rhizofiltration Roots of plants with dangling roots can absorb pollutants such as radioactive strontium-90 and cesium-137 and various organic chemicals. Sunflower Groundwater Soil
  19. 19. Tradeoffs of Phytoremediation Trade-Offs Phytoremediation Advantages Disadvantages Easy to establish Inexpensive Can reduce material dumped into land fills Produces little air pollution compared to incineration Low energy use Slow (can take several growing seasons) Effective only at depth plant roots can reach Some toxic organic chemicals may evaporate from plant leaves Some plants can become toxic to animals
  20. 20. Tradeoffs of Deep Underground Wells Advantages Safe method if sites are chosen carefully Wastes can be retrieved if problems develop Easy to do Low cost Disadvantages Leaks or spills at surface Leaks from corrosion of well casing Existing fractures or earthquakes can allow wastes to escape into groundwater Encourages waste production Trade-Offs Deep Underground Wells
  21. 21. Tradeoffs of Surface Impoundments Trade-Offs Surface Impoundments Advantages Disadvantages Low construction costs Low operating costs Can be built quickly Wastes can be easily retrieved if necessary Can store wastes indefinitely with secure double liners Groundwater contamination from leaking liners (or no lining) Air pollution from volatile organic compounds Overflow from flooding Disruption and leakage from earthquakes Promotes waste production
  22. 22. Secure Hazardous Waste Landfill Bulk waste Impervious clay Earth Water table Groundwater Clay cap Gas vent Topsoil Earth Sand Plastic cover Impervious clay cap Leak detection system Reactive wastes in drums Double leachate collection system Plastic double liner Groundwater monitoring well
  23. 23. Transition to a Low-Waste Society <ul><li>Recognizing that everything is connected…air, land, water, life. </li></ul><ul><li>There is no “away” as in “to throw away” (it goes somewhere) </li></ul><ul><li>Dilution is not always the solution to pollution (bioaccumulation is the reason why!) </li></ul><ul><li>Mimic nature: reuse, recycle, compost </li></ul><ul><li>Industrial Ecology (the “new” industrial revolution) a focus on pollution prevention by refusing to use toxins and reduction by by better design (waste = food) </li></ul>
  24. 24. Achieving a Low-Waste Society <ul><li>Grass-roots action is needed </li></ul><ul><li>Environmental justice must be considered (location of waste treatment and storage sites) </li></ul><ul><li>“ Not In My Backyard” (NIMBY) attitudes shift to “Not in Anyone’s Backyard” (NAMBY) or “Not On Planet Earth” (NOPE) </li></ul><ul><li>International treaties on Persistent Organic Pollutants (POPs) that should be avoided (notably the “Dirty Dozen”) </li></ul><ul><li>The Precautionary Principle is a good guide </li></ul>