The U.S. Department of Energy’s National Energy Technology Laboratory (NETL) has conducted a field study that monitored the induced fracturing of six horizontal Marcellus Shale gas wells in Greene County, Pennsylvania.
NETL conducted the study to determine the maximum height of fractures created by hydraulic fracturing at this specific location; and whether natural gas or fluids had migrated upward during or after hydraulic fracturing.
An Evaluation of Fracture Growth and Gas/Fluid Migration as Horizontal Marcellus Shale Gas Wells are Hydraulically Fractured in Greene County, Pennsylvania found no evidence of upward gas migration or brine migration.
(NETL) has released a technical report on the results of a limited field study that monitored a hydraulic fracturing operation in Greene County, PA for upward fracture growth out of the target zone and upward gas and fluid migration. Results indicate that under the conditions of this study, for this specific location, fracture growth ceased more than 5,000 feet below drinking water aquifers and there was no detectable upward migration of gas or fluids from the hydraulically-fractured Marcellus Shale.
NETL's results - though limited and site-specific - reinforce those of a study I blogged about yesterday. Fracking does not, so far, appear to threaten groundwater. Poor well integrity, however, does - along with surface leaks and spills.