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Coal Ash Disposal

Coal Ash Disposal. By Nick Garlisch Nick.garlisch@gmail.com. What is Coal Ash?. Coal ash is what remains after coal is burned When coal is burned, roughly 10% of the coal remains as ash Coal ash is comprised of several types of ash including fly ash, bottom ash, and boiler slag.

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Coal Ash Disposal

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  1. Coal Ash Disposal By Nick Garlisch Nick.garlisch@gmail.com

  2. What is Coal Ash? • Coal ash is what remains after coal is burned • When coal is burned, roughly 10% of the coal remains as ash • Coal ash is comprised of several types of ash including fly ash, bottom ash, and boiler slag

  3. Fly Ash • Fly ash is the ash that rises up and is trapped by the stack filters • About 74% of the ash generated is fly ash • Stack filtration devices such as scrubbers reduce fly ash emissions by around 95% • Around 5% of the fly ash produced is released into the atmosphere

  4. Bottom Ash • Bottom ash is too heavy to rise so it settles at the bottom of the boiler • About 20% of the ash generated is bottom ash

  5. Boiler Slag • Boiler slag is formed when the ash melts under the intense heat • It is collected at the bottom of the boiler and at the exhaust stack filters • About 6% of the ash generated is boiler slag

  6. Coal Ash Constituents • Coal ash contains pollutants such as arsenic, cadmium, lead, selenium, and other toxic metals that can cause cancer and neurological harm in humans • Other constituents of potential concern include mercury, aluminum, antimony, barium, boron, and thallium

  7. Should We Be Concerned? • Pollution from coal ash dumps significantly increases both cancer and noncancer health risks and degrades water quality in groundwater supplies • Unlined coal ash waste ponds pose a cancer risk 900 times above what is defined as acceptable • At least 23 states have poisoned surface or groundwater supplies from improper disposal of coal ash

  8. Magnitude of Ash Generated • The US derives over half its electricity from coal fired power plants • Burning this much coal results in nearly 140 million tons of coal ash produced each year • What happens to all that ash?

  9. Where it goes • Around 40% of the ash is reused as an additive in a variety of applications such as a cement substitute in concrete and a filler for asphalt • Coal ash is also used in construction projects to level out uneven terrain • The remaining 60% is disposed of in landfills

  10. Beneficial Reuse • Allows for the ash to be recycled instead of disposed • Decreases demand for cement and overall energy requirements for certain projects • Recycling reduces water consumption and greenhouse gas emissions

  11. FGD Gypsum • One way coal ash is reused is to make FGD Gypsum • FGD Gypsum is a product produced from the sulfur dioxide emissions control scrubbers • FGD Gypsum has many uses including agriculture, highway construction, cement production, water treatment, and glass making

  12. Agriculture

  13. Sham Recycling? • Concerns that the industry is using the ash improperly and labeling it recycling • Consumer products such as bowling balls and carpets • Golf courses • Placing the ash in deserted mines where it might leach into into groundwater- groundwater

  14. Regulations • No uniform federal standards • State by state regulations • Each state must meet baseline federal standards • EPA does not currently consider coal ash a hazardous waste

  15. Disposal • Coal ash is disposed of in surface impoundments (aka coal ash pond) where the ash is suspended in water • There are up to 1,300 impoundments nationwide • Some states have recently started requiring liners for new impoundments scheduled to be built • Catastrophic spills have occurred

  16. TVA Spill • A retention wall collapsed at a coal ash pond at the Tennessee Valley Authority’s Kingston Plant • Around 5.4 million cubic yards of wet coal ash spilled out of the ash pond • The spill flooded more than 400 acres and entered water systems used for drinking water

  17. TVA Spill • Elevated levels of radiation from those typically found in coal ash • Levels of radium 228 and 226 around 8 picocuries per gram, most coal ash is around 5-6 • Fears over exposure to airborne particulate matter • An underwater dam was constructed to prevent ash from moving further downstream

  18. Illinois • Illinois EPA has required new surface impoundments built after the early 1990’s to be lined • Groundwater monitoring wells have been installed at some but not all of these new impoundments • The following is a table of power plants with surface impoundments permitted under the NPDES program

  19. Illinois • Illinois EPA Bureau of Water issues permits for surface impoundments that recently have started to require liners and groundwater monitoring • Surface impoundments must be in compliance with Illinois groundwater and surface water quality standards • IEPA Bureau of Land can issue a permit for coal ash to be disposed in special waste landfills

  20. Proposed Regulation • The EPA is currently engaged in a rule making process to regulate coal ash • EPA has proposed two separate options for how it would regulate coal ash • Regulation would be under the Resource Conservation and Recovery Act (RCRA) subtitle C or subtitle D • Public comments were due November 19th

  21. Subtitle C • Coal ash would be considered a hazardous waste • State and federal enforcement • Permits requirements • Phases out the use of existing and new surface impoundments • Industry contends a hazardous label would end beneficial reuse and cost 12-13 billion dollars more per year which would be pushed onto consumers • Industry contends coal ash is not a hazardous waste

  22. Subtitle D • Coal ash would not be considered a hazardous waste • Citizen suit enforcement where states can act as citizens • No permit requirements • Surface impoundments would continue to be used but would require liners • Environmental groups think subtitle D regulation would be too weak

  23. How a Waste Becomes Hazardous • Under RCRA, a waste can become hazardous two ways • 1) The EPA administrator can list it as hazardous • 2) The waste can exhibit certain statutorily defined characteristics such as ignitability or corrosivity • The characteristics are described in detail in 40 CFR 261.4

  24. Is Coal Ash Hazardous? • Each quantity of coal ash generated is different because different coal plants burn different kinds of coal • Testing is the only way to be sure if an individual amount of coal ash is hazardous • Although generators are obligated to test their waste to determine if it is hazardous, few coal ash generators actually test

  25. What Will EPA Do? • The public comment period ended November 19, 2010 • EPA must respond to the concerns in these comments • EPA’s final decision will not be overturned unless it is found to be arbitrary and capricious • Environmental groups contend subtitle D will continue to provide inadequate regulation • Industry contends subtitle C will end beneficial reuse and cost consumers more money • What will EPA choose?

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