A panel of geologists, toxicologists, engineers and doctors that will peer-review a high-profile Environmental Protection Agency study of hydraulic fracturing will include Michel Boufadel, professor of civil and environmental engineering at Temple, as well as five other scientists from Pennsylvania. Hydraulic fracturing, used in natural gas exploration, is the process of injecting a high-pressure mix of chemically-treated water and sand underground to break apart a rock formation and release the gas.