Well water contaminants highest near natural gas drilling: study

maximum concentration from an extraction area sample was 161 micrograms per liter, or sixteen times the EPA safety standard set for drinking water. According to the EPA, people who drink water containing arsenic well in excess of the safety standard for many years “could experience skin damage or problems with their circulatory system, and may have an increased risk of getting cancer.”

  • Selenium was found in ten samples near extraction sites, and all of those samples showed selenium levels were higher than the historical average. Two samples exceeded the standard for selenium set by the EPA. Circulation problems as well as hair or fingernail loss are some possible consequences of long-term exposure to high levels of selenium, according to the EPA.
  • Strontium was also found in almost all the samples, with concentrations significantly higher than historical levels in the areas of active gas extraction. A toxicological profile by the federal government’s Agency for Toxic Substances and Disease Registry recommends no more than 4,000 micrograms of strontium per liter in drinking water. Seventeen samples from the active extraction area and one from the non-active areas exceeded that recommended limit. Exposure to high levels of stable strontium can result in impaired bone growth in children, according to the toxic substances agency.

    • “After we put the word out about the study, we received numerous calls from landowner volunteers and their opinions about the natural gas drilling in their communities varied,” Hildenbrand said. “By participating in the study, they were able to get valuable data about their water, whether it be for household or land use.

    “Their participation has been incredibly important to this study and has helped us bring to light some of the important environmental questions surrounding this highly contentious issue.”

    The paper also recommends further research on levels of methanol and ethanol in water wells.

    Twenty-nine private water wells in the study contained methanol, with the highest concentrations in the active extraction areas. Twelve samples, four of which were from the non-active extraction sites, contained measurable ethanol. Both ethanol and methanol can occur naturally or as a result of industrial contamination. Historical data on methanol and ethanol was not available, researchers said in the paper.

    The release notes that many from the research team are now conducting well water sampling in the Permian Basin region of Texas, establishing a baseline set of data prior to gas well drilling activities there.

    That baseline will be used for a direct comparison to samples that will be collected during and after upcoming natural gas extraction. The team hopes that these efforts will shed further light on the relationship between natural gas extraction and ground water quality.

    — Read more in Brian E Fontenot et al., “An evaluation of water quality in private drinking water wells near natural gas extraction sites in the Barnett Shale Formation,” Environmental Science & Technology (25 July 2013) (DOI: 10.1021/es4011724)