1. 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.
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2. High Volume, Slickwater Fracing from Long Laterals: The Concept
Not to scale
~ 5000 feet
Cap rock
The Lateral
Cap rock
~ 100 feet
Pay zone
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3. 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.
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Photo Courtesy T. Engelder

4. 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.
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5. 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
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6. Ideal Arrangement of Spacing Units
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8. 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.
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