First a quick note.  Loyal readers will know that I generally publish every Sunday evening.  The steady routine suits my nature.  I had to leave town unexpectedly on the 13th and have just returned.   Therefore, I did not publish the fifth and final entry of my series on water on April 15 as scheduled.   You’ll have to wait until the 29th for that.  But not to worry, I did uncover something interesting while I was away.
 
I spent the last week and a half in central Pennsylvania, smack dab in the middle of the Marcellus shale formation, ground zero for fracking operations east of the Mississippi.  While there, I read an article on drilling and water contamination.  The article noted that local groups were pushing to have the regulations which had been recently enacted for hydraulically fractured gas wells to also be applied to oil wells.  The article went on to describe a number of documented cases of water contamination from oil drilling operations in the area over a long period of time.
 
Reading this article made a light go off in my head.  As I have noted in previous columns, hydraulic fracturing in the US began in 1947 and has been applied to approximately 90% of all oil and gas wells drilled since then.  Since fracking has been so common for so long, I couldn’t figure out why water contamination, based on reports in the media, seemed to be a more recent phenomenon.
 
So I have been looking for reasons why fracking of gas wells might lead to more water contamination than fracking of oil wells. Over the last 5-10 years the number of new gas wells has vastly increased in proportion to oil wells.  Since natural gas consists primarily of methane, a small molecule, a gas well could contaminate a water source through a smaller opening than an oil well.  I also thought that perhaps the gas companies may have been drilling at greater depths, requiring higher pressure which could lead to more problems.
 
However, as I learned more about incidents of water contamination from gas wells, I found the problems to be much more mundane than the esoteric issues I had been considering.  The root causes of the incidents were simple things like improper construction of the concrete well casing which protects the well bore or the spilling of waste water on the ground after extracting it from the well.  Just standard every day incompetence rather than something complex or sinister.
 
These types of shortcomings and errors would lead to water contamination whether the well was drilled for oil, gas, or both.  When I read the newspaper article last week, it became clear to me that the recent gas well bonanza did not create a new source of water contamination but merely brought attention to one which had been around for a long time.
 
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