Having to remove  groundwater from the subsurface as part of gas production in the Marcellus shale could have a number of interesting implications, both practical and legal/regulatory.  It turns out that it may very well be  necessary to remove  significant quantities of groundwater as part of getting the gas out.  As stated in a USGS Report

The amount of water produced from most CBM (coal-bed methane) wells is relatively high compared to conventional natural gas wells because coal beds contain many fractures and pores that can contain and transmit large volumes of water.

I want to get a greater comfort level in terms of comparing CBM gas production wells to those proposed for the Marcellus shale.  Nevertheless, there is a strong likelihood that Marcellus shale wells will likewise involve production of a lot of water, brought to the surface from natural and hydraulically produced fractures. There are a number of very interesting implications of  this groundwater removal.  This water could contain contaminants (naturally occurring ones,  those resulting from injection of fluids, or from other sources such as buried wastes or subsurface sources of radio-isotopes).  Once pumped out, the water must be either used,  possibly re-injected, or treated and discharged.    Thus, one  implication is expense of treating and disposing of this water.  As stated in the USGS Report noted above:

For any CBM field, the cost of handling coproduced water varies from a few cents per barrel to more than a dollar per barrel and can add significantly to the cost of gas production. In some areas, the volumes of water produced and the cost of handling may prohibit development of the resource. (My emphasis.)

I wonder how much information exists on quantities and levels of contamination (current and potential) in the areas proposed for drilling, and accompanying plans for handling water slated for removal. It is not unlikely that discussion of these factors is being held back for a number of reasons.  For one, there is just a lot going on, and it’s hard to keep an eye on all the balls in the air.  For another, these projects are very multidisciplinary.   Communications between regulators in different areas (energy, mining, groundwater, surface water, etc.) is important, but could be impeded by workload and other factors.  I’ll include discussion of other implications of this groundwater removal in upcoming posts.




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