Why Is Shale Gas DevelopmentWhy Is Shale Gas Development“Unconventional”“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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HHigh igh VVolume, olume, SSlickwater lickwater FFracing from racing from LLong ong LLaterals: The Conceptaterals: The Concept

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~ 5000 feet

~ 100 feet Pay zone

Cap rock

Cap rock

Not to scale

The Lateral

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Early Joints at Taughannock Falls

J1

J2

Geneseo-Burket (Devonian black shale)Taughannock Falls State Park, Trumansburg, N.Y.

Photo Courtesy T. Engelder

Gas Producing Shales are Heavily Fractured Naturally

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Why Is Slickwater, High-Volume Fracing Why Is Slickwater, High-Volume Fracing from Long Laterals a Higher from Long Laterals a Higher

Risk to Human Health?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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Example: Dallas/Fort Worth Airport Property, Example: Dallas/Fort Worth Airport Property, Barnett Shale PlayBarnett 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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Ideal Ideal Arrangement of Spacing UnitsArrangement of Spacing Units

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Why Is Slickwater, High-Volume Fracing Why Is Slickwater, High-Volume Fracing from Long Laterals a Higher from Long Laterals a Higher

Risk to Human Health?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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