The Occurrence of Methane in Shallow Groundwater from Extensive PreDrill Sampling

On behalf of a major shale gas operator, sampling of over 20,000 water wells has been conducted from 2009 to the present, from shale-gas development areas across Pennsylvania, Ohio, and West Virginia. Sampling was conducted prior to Marcellus/Utica Shale-related exploration, drilling, and production activities in the vicinity of these water wells. The predrill samples have been analyzed for methane, ethane, and propane, as well as many inorganic parameters.

This presentation will explore the occurrence and distribution of methane in groundwater prior to unconventional gas development. GIS-based mapping and statistics will be used to evaluate the geographic distribution and relationship to bedrock geology. The relationships between methane and other parameters can also help explain methane occurrence, including parameters such as ethane and propane, alkalinity, TDS and major ions, barium, etc. 

Better understanding of methane in shallow groundwater will lead to better decision-making when evaluating potential impacts of shale gas development on water supplies and stray gas occurrence.