Water contamination associated with shale gas exploration and hydraulic fracturing in the U.S.: Wednesday, February 19th

Dr. Vengosh is a Professor of Geochemistry and Water Quality at the Nicholas School of Environment in Duke University.  He also is appointed at the Department of Civil and Environmental Engineering at Duke University.  Dr. Vengosh received his BS and MS from the Hebrew University of Jerusalem, Israel and his PhD from the Research School of Earth Sciences, Australian National University, Canberra, Australia.

Currently Dr. Vengosh’s research includes the energy industry’s impact on water quality, environmental health related to human exposure of naturally occurring contaminants in drinking water and the salinization of water resources from human activities and climate change.

After a snow delay Dr. Vengosh spoke to the One Health Intellectual Exchange beginning with an introduction to sources of energy in the USA.  He explained that Natural Gas has recently overtaken Coal as the most produced energy in the US.  Here’s a table of the percent of energy produced in the US.

Natural Gas        31%
Coal                     26%
Crude Oil            21%
Nuclear               10%
Renewables        16%  which include wind, solar, hydropower, biomass etc.

It is projected that as natural gas production increases the use of oil will decrease a bit.  Other sources will stay about the same.  As the US produces more natural gas, we will begin to export it to Mexico and Canada which may increase prices.
Water quality is affected by several of the different energy industries such as mountaintop and sub-surface coal mining, shale gas fracking, coal ash disposal sites, tar sands etc.

What is myth and what is reality?  Several mainstream movies such as Gasland and The Promise Land have stirred the public’s interest (and opposition) to fracking.  Dr. Vengosh explains that there are lots of other chemicals used in energy harvesting which are just as bad but receive no press or protest.

Why is gas so important?  Natural gas is everywhere in the United States and around the world.  Using more natural gas would cause a decrease of wood burning as a fuel source.

What is fracking? 



What are the environmental risks of fracking?
  • methane emissions in the air and water- methane causes more build-up of greenhouse gases
  • 7-15 million liters of water per well is used- this is an issue where water is scarce.  The industry is moving towards 100% water recycling.  (Forty per cent of water used in the US is in coal and nuclear plants.)
  • fracking chemical spills contaminate the immediate area
  • air and water pollution at different stages of gas production
  • disposal of the fracking fluids and the waste water
  • health implications on quality of life

Of the above mentioned risks, 99% of the issues are with the waste water disposal.  Waste water is state regulated, not federally regulated.  There is a question if the states have proper regulations to monitor deep injection wells or is the waste water moved to another state?  He adds that earthquakes are not a major issue.

Some results from his studies:
1.       Stray gas contamination is real.  Meaning that water does catch on fire, but not always.
2.       Need to establish tools to detect fracking fluids in the environment.
3.       Disposal of shale gas waste water results in contamination and with radioactivity build up.

Water becomes contaminated from gas leaking from well casings, surface spills and waste water treatment and storage.  It is determined that living close (<1km) to a drill site will increase the per cent of methane (also ethane and propane) in the water.  Living > 10km away reduces this risk.  There has been no evidence of fracking fluids found in active wells.

What are fracking fluids?  They are proprietary chemicals but they do contain high salinity, Bromide, Strontium, NORM (Naturally Occurring Radioactive Materials) and organics including benzene, toluene, ethlybenzene, xylene and many other chemicals.

How/where can we treat fracking fluids?
  • Municipal treatment facility- these are inadequate since the fluids will affect the domestic waste water.  Bromide in the water causes carcinogenic byproducts.
  • Brine treatment facility-inadequate for halogens and radioactivity
  • Deep well injection- this may induce seismicity
  • Recycle to fracking- limited by water chemistry causing scaling and radioactivity

What are the solutions?
  • Blend acid mine drainage and fracking fluids.  The SO4 from the acid will react with the Br, Sr and Rn capturing the radioactivity.
  • Completely recycle the fracking fluids.
  •  Must have a private well >1 km from a drilling site.



Submitted by Barbara A. Wujciak, OD

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