A recent study published in Environmental Science and Technology found “elevated levels of numerous metals and chemical compounds” from 550 groundwater samples collected from private and public supply water wells in Texas. The wells draw their water from aquifers throughout the 5,000 square miles Barnett shale formation of Texas. While the University of Texas Arlington (UTA) study did not directly attribute the contamination from hydraulic fracturing activities taking place in the area, the authors did conclude, “It is more likely that it (fracturing) has had an effect on water quality.[i]
“We detected multiple volatile organic carbon compounds throughout the region, including various alcohols, the BTEX family of compounds, and several chlorinated compounds. These data do not necessarily identify UOG activities as the source of contamination; however, they do provide a strong impetus for further monitoring and analysis of groundwater quality in this region as many of the compounds we detected are known to be associated with UOG techniques.”[ii]
Among the 10 different metals and 19 chemical compounds found in the water samples were BTEX, or benzene, toluene, ethyl benzene and xylenes. These compounds are carcinogens.
In June 2015, the Environmental Protection Agency released an assessment of the potential impacts of hydraulic fracturing on drinking water. The process, which has been used since the 1940s in vertical wells, has evolved with technology. It is now employed in more unconventional hydrocarbon formations to extract oil and gas, including shales, tight formations and coalbeds. The EPA estimates that between 25,000 and 30,000 new wells were drilled in the United States between 2011 and 2014. From 1990 to 2013, fracturing took place in 25 states with half of the wells in Texas. Approximately 9.4 million people resided within one mile of a hydraulic fracturing well between 2000 and 2013, and 6,800 sources of drinking water serving 8.6 million people were located within in the same distance in 2013.
The EPA concluded, “There are above and below ground mechanisms by which hydraulic fracturing activities have the potential to impact drinking water resources. These mechanisms include water withdrawals in times of, or in areas with, low water availability; spills of hydraulic fracturing fluids and produced water; fracturing directly into underground drinking water resources below ground migration of liquids and gases; and inadequate treatment and discharge of wastewater.”
The EPA “did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States.”[iii] Despite the EPA’s finding, environmentalists suggest that the UTA study proves that hydraulic fracturing is responsible for the pollution and that contamination from the process is a bigger problem than what the EPA suggests.
Teledyne Tekmar has published a few blogs relating to Hydraulic Fracturing. If you are interested in reading the other posts, click here Hydraulic Fracking Blog Posts.Tekmar has also published a couple application notes on RSK175.
Two Headspace Solutions for the Analysis of Dissolved Gases in Water by Method RSKSOP-175
An Alternative Method to RSK 175 using a Purge and Trap Concentrator and GC/FID
[i] http://www.star-telegram.com/news/business/barnett-shale/article24830848.html#storylink=cpy
[ii] http://pubs.acs.org/doi/pdf/10.1021/acs.est.5b01526
[iii] http://www2.epa.gov/sites/production/files/2015-07/documents/hf_es_erd_jun2015.pdf