Escaping methane and vocs.
Drilling rig 35 metres high.
Lung-damaging ozone pollution when truck fumes mingle with vocs.
400 tanker trucks per site, carrying water and supplies.
Casing of steel (malleable) surrounded by cement (rigid). Critics point out the combination cannot have the permanency claimed by industry. Industry claims casing failure rates of under 1%; independent researchers 6-7 %. In the long run, all casings will fail.
Methane gas and toxic chemicals can contaminate the water supply.
Frack fluid rises again, now mixed with heavy metals (like lead and arsenic) and radioactive substances leached from the rocks. Methane concentrations are 17 times higher in drinking-water wells near frack sites.
Slickwater – what’s in frack fluid n 98.5% water n 1% sand n 0.5% chemicals
In the US over 600 chemicals have been tracked down by independent researchers – companies don’t disclose what they use. Known toxins, including carcinogens and neurotoxins, are among them.
Chemicals are used to reduce friction (that’s why it’s called slickwater); also acids, rust and scale inhibitors, anti-microbials, gelling agents and solvents.
If, say, 10 million litres of water are used to frack one well, then that makes 50,000 litres of chemicals. For a 1,000-well field, the amount of chemicals used is staggering, even allowing for recycling of frack fluid. Which is why industry is making promises (outside the US) of greatly reduced chemical use and even chemical-free fracking.
Natural gas is released from the cracked rock.
Natural gas flows from fissures into well
Sand keeps fissures open
Well Mixture of water, sand and chemical agents
Frack fluid pushed in great volumes at high pressure to crack the gasbearing shale.
Punctured casing allows fluid to burst through.
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