Fracking Fluid

Compound Purpose Common Application
Acids Helps dissolve minerals and initiate fissure in rock (pre-fracture) Swimming pool cleaner
Sodium Chloride Allows a delayed breakdown of the gel polymer chains Table salt
Polyacrylamide Minimizes the friction between fluid and pipe Water treatment, soil conditioner
Ethylene Glycol Prevents scale deposits in the pipe Automotive anti-freeze, deicing agent, household cleaners
Borate Salts Maintains fluid viscosity as temperature increases Laundry detergent, hand soap, cosmetics
Sodium/Potassium Carbonate Maintains effectiveness of other components, such as crosslinkers Washing soda, detergent, soap, water softener, glass, ceramics
Glutaraldehyde Eliminates bacteria in the water Disinfectant, sterilization of medical and dental equipment
Guar Gum Thickens the water to suspend the sand Thickener in cosmetics, baked goods, ice cream, toothpaste, sauces
Citric Acid Prevents precipitation of metal oxides Additive in food and beverages
Isopropanol Used to increase the viscosity of the fracture fluid Glass cleaner, antiperspirant, hair coloring
Source: DOE, GWPC: Modern Gas Shale Development in the United States: A Primer (2009).

After the wells on a pad are drilled, cased and cemented,
a device perforates the horizontal part of the production
pipe to make small holes in the casing, exposing the
wellbore to the shale. Then a mixture, commonly known
as fracking fluid, of water (90 percent), sand (9.5 percent)
and chemicals (0.5 percent) is pumped into the well
under high pressure to create micro-fractures in the shale
and free the natural gas or oil.

The sand in fracking fluid keeps the fractures open after
the pressure is released, and the chemicals are chiefly
agents to reduce friction and prevent corrosion.

The chemical disclosure registry provides
information on hydraulic fracturing fluid used in over
117,600 wells. Industry activity is subject to a number of
federal and state laws, including the Safe Drinking Water
Act, the Clean Water Act, the Clean Air Act and the
National Environmental Policy Act.