Lower Kittanning Coal Seam, Clarion University Campus

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1 Coal

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5 Lower Kittanning Coal Seam, Clarion University Campus

6 Varieties of Coal Anthracite: "hard coal," anthracite is formed from bituminous coal when great pressures developed in folded rock strata during the creation of mountain ranges. Anthracite has the highest energy content of all coals and is used for space heating and generating electricity. Bituminous: Bituminous coal the type most commonly used for electric power generation in the U.S. Subbituminous: Subbituminous coal formed from the remains of trees, ferns and other plants that existed and died during the time of the dinosaurs. A dull black coal Lignite: Increased pressures and heat from overlying strata caused buried peat to dry and harden into lignite. Lignite is a brownish-black coal with generally high moisture and ash content and lower heating value.

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8 Where is coal mined? (millions of tons, 2004) 1980: Appalachia 438 Western 210

9 Coal 1994 Petroleum liquids 31.2 Units in table are billion kilowatt hours. Petroleum Coke 14.2 Natural gas Other gases 11.6 Nuclear 806 Other 10.4 Hydro Biomass 55.9 Geothermal 14.9 Solar/PV 0.8 Wind 52

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11 Coal Facts Total demand for U.S. coal reached 1.05 billion tons in Nearly half of U.S. electricity is generated from coal. 9 out of every 10 tons of coal mined each year in the U.S. is used for domestic electricity generation. Each person in the U.S. uses 3.4 tons of coal annually. There are approximately 600 coal generating facilities (1,470 generating units) and 1,100 manufacturing facilities using coal in the U.S., according to the U.S. Energy Information Administration (EIA). EIA estimates that 73% of all coal-based generating capacity was 30 years or older at the end of 2010.

12 More Coal Facts The U.S. has 261 billion tons of recoverable coal reserves That is a 235-year supply at current rate of use Coal accounts for approximately 94 percent of the nation's fossil energy reserve Coal is found in 38 states, under 458,600 square milesor about 13 percent of the nation's land area

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14 A historic shift in electric generation 331 recently announced closings of old coal fired power plants, mostly in 2015, and including 6 in Pennsylvania 258 new natural gas fired power plants currently under construction Coal market share has fallen from 52% in 2000 to 39% in 2011

15 Who to Thank for Healthier and Cleaner Air and Water? Interstate Toxics Rule (EPA) Interstate Toxins Rule (2012) Cross-state Air Pollution Rule (in progress) Marcellus Shale Industry (various corporations that people love to hate (while buying fuel from them))

16 Environmental Effects of Coal Use Water pollution Subsidence Loss of farmland and forests Air Pollution Waste Disposal Carbon flux

17 Methods of Mining Coal Deep Mines Longwall Mining Surface Mining

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23 Formation of acid mine drainage Fracturing of overburden allows groundwater to percolate through bedrock strata that were formerly impermeable These strata often contain high concentrations of pyrite (FeS 2 ) Groundwater leaches pyrite from the bedrock, carries it to the surface where it reacts with oxygen 4FeS 2 +15O 2 +14H 2 O > 4Fe(OH 3 ) + 8(SO 4 ) H +

24 Aluminum floc from AMD -

25 Scope of Problem: Pennsylvania Over 3,000 miles of stream have been degraded in PA Daily influx of more than 1 billion gallons of acid-mine drainage Economic cost associated with loss of recreational fisheries alone exceeds 67 million / yr Cleanup costs for PA estimated to exceed 15 billion

26 SMCRA: Surface Mine Control and Reclamation Act of 1977 Regulates current mining practices Permitting: A reclamation plan is developed for each mine at the time of permitting Bonding: Coal mining companies must post a bond to guarantee reclamation of land Regulatory: Created OSM, Office of Surface Mining Performance standards: regulations pertaining to operations and reclamation (restore natural vegetation) Land restrictions, no mining in parks, etc.

27 SMCRA: Surface Mine Control and Reclamation Act of 1977 Created the abandoned mine lands (AML) fund for reclamation work Taxes coal sales (35 cents/ ton) to fund reclamation work (AML fund) Reauthorized in 2006 for 15 years Current expenditures about 500 million per year PA DEP commits to spending 30% of the 1.4 B it will receive for water quality restoration PA has spent some 650 M on restoration, total price is as high as 15 B

28 Methods of Remediating AMD Diversion of surface and ground water Chemical (Active) Treatment Passive Treatment

29 Water Diversion Groundwater diversions drains Revegetation, Restoration of soil profiles Surface contouring Surface caps

30 Chemical Treatment addition of: Calcium cabonate (lime) Calcium hydroxide Sodium carbonate (quicklime) Sodium hydroxide (caustic soda) to mine effluent Calcium compounds cost less, but are less soluble and require mixing aid

31 Precipitates Formed Through Chemical Reaction The goal of chemical treatment systems is to allow alkaline material to combine with the mineral acidity to precipitate the metals out of the AMD. This neutralizes the effluent so it can be released without causing harm to the environment.

32 Passive Treatment Systems Designed to: Generate Alkalinity Neutralize Acid Precipitate Metals Resulting in overall improvement in water quality of discharge before entering stream.

33 Components of passive treatment Anoxic Limestone Drains (ALD) Settling Ponds-aerobic wetlands Vertical Flow Wetlands / Successive Alkalinity Producing Systems (SAPS) Function: add alkalinity, allow metals to settle out of solution

34 REM Passive Treatment System near Corsica, PA

35 Strattanville-Reed Treatment System

36 Recycling Iron Hydroxide

37 Issues Cost-effectiveness Longevity Compliance with Clean Water Regs

38 Mill Creek Watershed

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40 8 Right SysDys Left SysDys 7 Field ph Year Figure 6: Howe Bridge Discharge ph over Time

41 Acidity Fe Mn % Removal Figure 5. Removal efficiency for acidity, iron, and manganese at the Howe Bridge passive treatment system over time.

42 Additional Environmental Issues Associated With Coal Mining Longwall mining and subsidence Loss of farmland for forests Mountain Top removal Disposal of Fly-ash

43 Longwall Mining 100 Operations in US, mostly in Appalachia 31% US Coal production

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51 Damage to homes Types of damage Cracked masonary Damaged foundations Cracked plaster Lost water supply (wells) Damage to roads and railways Subsiding streams, loss of surface water

52 Mountaintop Removal Up to 1000 of overburden moved into adjoining valley

53 Broad extent in Appalachia, with more than 400,000 acres affected

54 Valley Fill

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56 Websites

57 Legal protection against mountaintop removal SMCRA 1977 prohibits surface mining within 100 ft. of perennial or intermittent streams 2006 EPA proposed changing this rule to minimize the destruction of fish and wildlife to the extent possible 2010 EPA changed rule to strictly regulate water quality 300 mg/l TDS

58 Legal protection against mountaintop removal Clean Water Act of prohibits industries from dumping waste into waterways EPA 2006 rule change states that debris from the mountaintop is not waste and therefore, companies are free to dump material into valleys

59 Waste Disposal Flyash the ash captured from Chimney of coal fired boilers Bottom ash captured from bottom of furnace Silicon dioxide, aluminum oxide, iron oxide, calcium oxide arsenic, beryllium, boron, cadmium, chromium, chromium VI, cobalt, lead, manganese, mercury, molybdenum, selenium, strontium, thallium, and vanadium, along with dioxins and PAH compounds Nearly half is recycled (portland cement, bricks, roadbeds) Often stored on site, eventually remainder is placed into landfills

60 Flyash wasteproduct of burning coal

61 Kingston TN million cubic yards 1.4 Billion cleanup

62 Minerals Fast Facts Every American uses an average of nearly 40,000 pounds of newly mined materials each year Telephones are made from as many as 42 different minerals, including aluminum, beryllium, coal, copper, gold, iron, limestone, silica, silver, talc and wollastonite. A television requires 35 different minerals, and a computer requires 30 minerals The construction industry accounts for approximately 51 percent of US copper demand. Silver's largest market use is for industrial applications, particularly as an electrical connector. Jewelry is the second largest use of silver. The Toyota Prius plug-in-hybrid requires about 50 pounds of rare earth metals for its motor and battery.

63 Gold Mines (Zortman-Landusky)

64 Cyanide Heap-Leach Gold Mining Began in 1970 s Allows the processing of low grade ore 35 tons of ore per ounce of gold

65 Iron Mines

66 Kennecott Mine, Utah Copper Mines

67 Bartow, FL Phosphate Mines

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