Despite the fact that there was a 2004 study by the U.S. Environmental Protection Agency (EPA) which was unable to found the evidence which would suggest frack drilling causes water pollution there are still many environmentalists and scientists who believe that frack drilling could easy become a source of major water pollution.
Frack drilling is the method of extracting natural gas by shooting chemical-laced water underground, and this can lead to poisoned water and major underground water pollution. In fact, there have been dozens of US landowners who have confirmed that their water become poisoned after the well operators started with frack drilling in nearby area.
Since the EPA 2004 frack drilling study was the subject of many controversies, EPA is already conducting its second, more comprehensive study, which should be completed by 2012.
Frack drilling has become very popular in many US states, and this has been one of the most important technological advances in drilling natural gas wells which has lead to significant decline in natural gas prices over the last few decades.
This issue could easily turn into technology vs ecology showdown, with the winner most likely to be decided by the outcome of the new EPA study. In the meantime it has to be said that in Ohio alone, in the last 10 years, there have been more than 14000 notices of violation against well operators.
Industries and well operators are of course denying any connection between frack drilling and water pollution saying that there hasn't been any study to confirm that frack drilling causes underground water pollution.
One thing is certain, in years to come we will certainly hear more about this issue. Especially if natural gas becomes the major part in new US energy policy.