Fracking, which mines natural gas using horizontal, hydraulically fractured wells, is widespread across Pennsylvania, with high-volume horizontal hydraulic fracturing (HVHHF) from the Marcellus and Utica shales covering up to 280,000 km² of the Appalachian Basin.
A new paper in the Annals of the New York Academy of Sciences by Dr.Erik Kiviat, of the Hudsonia ecology group, says that natural gas wells are a threat to biodiversity, including pollution from toxic chemicals, the building of well pads and pipelines, and changes to wetlands.