pknoerr wrote:
So before you worry about what is being introduced into petroleum bearing rock formations miles deep in the earth, spend a few minutes to go look at the known sites of environmental risks that have already been assessed by your State or Provincial Environmental Agency.
PK ... the main issue with fracking is not seepage from geologic formation miles deep (although this has not yet been ruled out), but a failure of well integrity (casing or cementing) with the high pressures, gas pockets, and large volumes of water and other fluids that are involved. Geological instability from low level earthquakes doesn't help matters any, either.
Quote:
Cementing is the obvious “weak link,” according to Anthony Gorody, a hydrogeologist and consultant to gas companies who has been a defender of fracking. Other scientists emphatically agree. “If you do a poor job of installing the well casing, you potentially open a pathway for the stuff to flow out,” explains ecologist and water resource expert Robert B. Jackson of Duke University's Nicholas School of the Environment.
http://dx.doi.org/10.1038/scientificamerican1111-80Flowback water is an additional concern:
Quote:
"horizontal fracking requires enormous volumes of water and chemicals. Huge ponds or tanks are also needed to store the chemically laden “flowback water” that comes back up the hole after wells have been fractured" ...
Then the flowback water has to be managed; up to 75 percent of what is blasted down comes back up. It is laden not only with a cocktail of chemicals—used to help the fracking fluid flow, to protect the pipe and kill bacteria, and many other purposes—but often with radioactive materials and salts from the underground layers. This toxic water must be stored on-site and later transported to treatment plants or reused. Most companies use open-air pits dug into the ground. Many states require the bottoms of the pits to be lined with synthetic materials to prevent leakage. Some also require the pits to be a sufficient distance from surface water. The problem is that even when proper precautions are taken, pit linings can tear, and in heavy rains the pits can overflow.
http://dx.doi.org/10.1038/scientificamerican1111-80If they regulated the industry better (see Cheney 2005 Energy Act exemptions), there would be fewer mistakes, better handling of waste, and fewer issues with groundwater contamination around fracking sites from leaky wastewater storage pools and well failures.
Add to this air quality concerns. And we are just starting to tackle this issue now as a result of a court decision in 2009 (and with mixed results).
Quote:
EPA altered the final regulations to offer a key concession to the natural-gas industry, which had raised concerns about being able to comply with the proposed regulations issued last year.
Under the final rules, companies can comply with the standards until 2015 using flaring, which reduces harmful emissions by burning off the gases that would otherwise escape during natural-gas drilling. After 2015, companies will need to install so-called “green completions,” which are technologies that capture harmful emissions.
http://thehill.com/blogs/e2-wire/e2-wir ... r-fracking