Why Is Shale Gas Development “Unconventional” Because it requires 3 technologies only recently combined to make gas production from shales technically and economically feasible. Directional drilling: needed to access a thin layer of shale with long laterals. High frac fluid volumes: needed to stimulate gas release from many existing fractures. Slickwater: needed to control the amount of power needed to pump large volumes of frac fluids, at high pressures, quickly, over long distances, through small diameter casing. CHE_Nov 9, 2010_Ingraffea

High Volume, Slickwater Fracing from Long Laterals: The Concept Not to scale ~ 5000 feet Cap rock The Lateral Cap rock ~ 100 feet Pay zone CHE_Nov 9, 2010_Ingraffea

Early Joints at Taughannock Falls Gas Producing Shales are Heavily Fractured Naturally J1 J2 Geneseo-Burket (Devonian black shale) Taughannock Falls State Park, Trumansburg, N.Y. CHE_Nov 9, 2010_Ingraffea Photo Courtesy T. Engelder

Why Is Slickwater, High-Volume Fracing from Long Laterals a Higher Risk to Human Health? Requires much higher well density, many wells per square mile. Requires much more industrial development over large areas, heavy equipment operating 24/7/365. Requires much higher volumes of fracing fluid, millions of gallons per well. Produces much higher volumes of waste fluids and solids containing hazardous materials: frac fluid chemicals, heavy metals, NORMS. Produces much higher volumes of fugitive emissions of methane. CHE_Nov 9, 2010_Ingraffea

Example: Dallas/Fort Worth Airport Property, Barnett Shale Play 53 pads on 18,076 acres Each red line is a well Almost complete coverage Patchwork, mostly ideal units One developer CHE_Nov 9, 2010_Ingraffea

Ideal Arrangement of Spacing Units CHE_Nov 9, 2010_Ingraffea

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Why Is Slickwater, High-Volume Fracing from Long Laterals a Higher Risk to Human Health? As number of wells and volumes of waste increase, probability of accidental releases of hazardous materials into air and groundwater increases. Cumulative effects on air and water from purposeful emissions into the atmosphere and releases into groundwater are unknown. Increased production and burning of natural gas and its liquid companions (e.g. ethane, propane, butane) increases emission of GHG’s. CHE_Nov 9, 2010_Ingraffea