IMPACT OF OIL AND GAS INDUSTRY WASTEWATER ON WATER AND SEDIMENT CHEMISTRY IN ONE STREAM IN WEST-CENTRAL PENNSYLVANIA

Hydraulic fracturing fluid is composed of large volumes of water that contain roughly 1% chemical additives, and proppant. Fracking fluid is injected during shale gas development and returns to the land surface mixed with formation waters produced during gas extraction. These waters are treated several ways, including processing at centralized waste treatment (CWT) facilities. Treated wastewater from conventional oil and gas wells are discharged at Blacklick Creek, PA, according to recommended PA water standards. However, the treatment plant has been subject to fines from the EPA. Water and sediment chemistry near the discharge point were tested in several ways: direct measurement of electrical conductivity (EC), UV/visible spectrometry of in-stream water, and laboratory analysis. Laboratory analysis included dissolved organic carbon (DOC), major anions, and cations, and metals. Preliminary results indicated very high salt concentrations downstream from the treatment discharge, and spectral results suggest the presence of organic compounds in the effluent. Water analyses will be compared to chemical analyses of the sediments of the creek.