If you pay attention to the television ads paid for by the oil and gas industry, fracking is the best thing since canned beer. Enhanced recovery techniques have led to a boom in domestic fossil fuel production, making the US first in natural gas production according to the ads. That ought to make the jingoists yell, "buyeh" and set off some seasonal fireworks.
The EPA meanwhile has issued an assessment of fracking and horizontal drilling effects on groundwater quality. The report is significant for the questions it does not answer, which are quite a few, because the industry would not submit to the rigorous testing the government wanted to determine if their is scientifically proven link to drinking water contamination. The study did say that the techniques do have the potential to contaminate drinking water. Duh. The greatest risks to drinking water are spills, water withdrawals, wastewater releases and migration of gas and oil underground. Thank you, Captain Obvious. The agency went so far as to say there is no evidence of widespread contamination by fracking or slant drilling. The number of cases of contamination or possible contamination are small compared to the estimated 25-30,000 enhanced recovery wells drilled between 2011 and 2014. The industry touts the EPA's failure to discover widespread contamination as confirmation of its safety record. Industry critics say it merely shows the agency's lack of before and after data on specific water sources. The report repeatedly cites the need for this type of comprehensive study. The agency, cowed by the powerful fossil fuel lobby, backed out of a well contamination study in Pavillion, Wyoming after its methods were critized by the industry, and dropped similar research in Texas and Pennsylvania. Despite the political pressure, EPA has found contamination linked to hydraulic fracturing in the past. A 2010 well blow-out in Killdeer, ND caused fracking fluids to contaminate the Killdeer aquifer with brine and tert-butyl alcohol.
Another source of pollution from all the drilling activity in the "Saudi Arabia of Gas" are methane releases to the atmosphere. Since 2010 according to the Pipeline and Hazardous Materials Administration 12.8 billion cubic feet of natural gas has escaped into the atmosphere from the nation's network of gas transmission and distribution lines--enough energy to heat 170,000 homes for a year. Burning natural gas for energy is less dirty than burning coal, emitting about half the amount of CO₂ per kilowatt of electricity with no particulates of mercury or sulfur dioxide. But methane has about 30 times the potential warming effect of CO₂ over a century. With the amount of leakage involved natural gas is loosing its greenhouse gas advantage over coal; according to the Environmental Defense Fund if only 3% of gas produced escapes, natural gas plants have no advantage over coal plants. If the industry will not clean up its act and invest in new infrastructure, government will have to require it.