Shale gas was first used in the U.S. to light homes at Fredonia, New York in 1821.
The use of shale gas is not new.
Hydraulic fracturing was first used in Texas to stimulate oil-wells in the late 1940s.
Fracking is also not new.
What is new is the development of technical procedures that allow fracking to be used in shale to produce economic quantities of natural gas and additional oil.
Environmentalists have raised concerns about fracking, now that fracking has created an abundance of natural gas. Contamination of water supplies, specifically wells and aquifers, and the use of water are the major concerns raised by them.
Widely disseminated pictures of tap water catching fire have been used in an effort to scare people and stop fracking.
Does fracking cause natural gas to contaminate water supplies?
If there is a poor cement job around the drill pipe, it can allow natural gas to migrate to the surface. This gas can enter well water or aquifers. This has been the case with old natural gas wells that didn’t involve fracking, and possibly with new wells. Gas migration is not due to fracking, but rather to the cement seal around the drill pipe.
Gas migration can also occur when drilling water wells.
Gas migration can be prevented with proper cementing.
What about contaminating aquifers with the chemicals used in fracking?
The contamination of aquifers from fracking is virtually impossible since the shale is usually located thousands of feet below aquifers. Real time fracture propagation can be monitored using observations from instruments so that fractures can be prevented from growing beyond the shale. In addition, shale becomes more plastic as it gets shallower which reduces the potential for propagation of fractures into aquifers when shale is located closer to the surface.
A large quantity, 50% or more, of the fluids used in fracking are removed from the well. If these fluids are not stored properly on the surface or are not properly disposed of, they can contaminate surface waters. There have been reports of flow back fluids spilling from containment ponds onto fields or into surface waters such as creeks, ponds or tributaries.
Flow-back water contains sand, tiny amounts of chemicals, most of which are commonly used in and around homes, but where some are dangerous, and trace amounts of radioactive materials that occur naturally in shale. Thus far, tests have shown that radioactivity levels have been below federal standards for safe drinking water.
Preventing flow-back water from spilling is manageable, as is the proper disposal of the water. It’s in the self interest of drilling companies to prevent spilling flow-back water.
Fracking has also been criticized for its use of large quantities of fresh water. This should not be an issue east of the Mississippi where less than 10% of available fresh water from rainfall is actually used. There may be areas west of the Mississippi where water usage could become an issue. More importantly, efforts are underway to reuse fracking water which would largely eliminate this concern.
New developments to mitigate the above concerns are occurring constantly, and these developments could easily eliminate these concerns. There are reports that Canadian companies have used liquefied petroleum gas (LPG), consisting mostly of propane, instead of water for fracking. Poland is experimenting with vibration for fracking.
Technology is likely to improve fracking, its efficiency and safety.
Currently, fracking isn’t perfect, but the concerns are manageable and the benefits are huge.
Fracking has created an immense supply of low-cost natural gas. Low-cost natural gas reduces the cost of heating for people using natural gas to heat their homes. It provides low-cost electricity and a likely replacement for many older coal-fired power plants. It provides fuel for trucks and busses and possibly for cars.
Problems should be kept in perspective and balanced against the benefits provided by fracking.
Note: Sources include a strategy paper from the European Centre for Energy and Resource Security, and the 2004 EPA report on Coalbed Methane Fracking.
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