A retrospective case study of perceived water well interference by coal bed methane fracking

Although water well concerns are one of the most frequently cited concerns about hydraulic fracturing, few case histories are available.  A 2004 case study of perceived water well interference by ‘stimulation’ of a coal bed methane well is reviewed here to highlight the challenges for both the energy industry and domestic well owners contributing to a lack of a ‘social license to operate’ in parts of Canada.

The circumstances around the perceived water well interference were evaluated by reviewing relatedenvironmental consulting reports, water well records, baseline water well testing and energy well activities in the region, and through discussions with various individuals directly involved. The timeline of events suggest the water well could have been affected by the stimulation. The energy well perforations were unusually shallow when compared to other energy wells in the region, and similar in elevation to the domestic use aquifer.

Although the evidence suggests that the energy well stimulation may have been related to the perceiveddomestic water well interference, subsequent stimulation in energy wells located even closer to the rural residence (but perforated at greater depth) did not cause observed interference in a replaced domestic water well on the same property.

Appropriate evaluation of water well complaints is clearly challenging.  Dedicated monitoring systems are seldom used to evaluate hydraulic fracturing impacts in shallow groundwater. The industry reportedly deals with a large fraction of apparently invalid water well complaints. In part in an effort to minimize invalid water well complaints, they i) do not disclose details about confirmed water well complaints that are appropriately addressed and ii) do not provide any notification of energy activities in a given region. The latter can prevent the timely collection of appropriate information, with subsequent the difficulties in conducting a ‘post-­mortem’ analysis and perceived water impacts whose cause(s) are difficult to assess.