Evaluating a groundwater supply contamination incident attributed to Marcellus Shale gas development

TLDR

High‑volume hydraulic fracturing is increasingly used to extract oil and gas from low‑permeability rocks, yet public concerns persist that the chemicals involved could migrate into aquifers. The authors aim to encourage the systematic analysis and public release of data on contamination incidents to prevent future problems through improved management practices. They report a Marcellus Shale gas development incident in which natural gas and organic contaminants migrated laterally across kilometers of rock, contaminating a potable aquifer at shallow to intermediate depths, with the contaminants traced to drilling or HVHF fluids and detected by specialized instrumentation.

Abstract

Significance New techniques of high-volume hydraulic fracturing (HVHF) are now used to unlock oil and gas from rocks with very low permeability. Some members of the public protest against HVHF due to fears that associated compounds could migrate into aquifers. We report a case where natural gas and other contaminants migrated laterally through kilometers of rock at shallow to intermediate depths, impacting an aquifer used as a potable water source. The incident was attributed to Marcellus Shale gas development. The organic contaminants—likely derived from drilling or HVHF fluids—were detected using instrumentation not available in most commercial laboratories. More such incidents must be analyzed and data released publicly so that similar problems can be avoided through use of better management practices.