Research on Production and Disposal of Waste Materials from Gas and Oil Extraction in Pennsylvania Marcellus Shale
Posted: January 6, 2013
Advances in technology have opened the doors wide for natural gas exploration and extraction throughout the world. Little research has been done regarding the quantity, transport, and disposal methods of wastes produced during the extraction process. Research conducted by Kelly O. Maloney, US Geological Survey-Leetown Science Center and David A. Yoxtheimer, Penn State Marcellus Center for Outreach and Research, examined the quantity of water produced by gas extraction activities from Pennsylvania Marcellus for the 2011 year.
Maloney and Yoxtheimer’s research reviewed the Pennsylvania Department of Environmental Protection (PA DEP) production and waste reports. Amounts of gas, condensate and oil produced by county for 2011 were reviewed as well as major types of waste (basic sediment, brine, drill cuttings, drilling fluids, flowback fracturing sand, frac fluids and spent lubricants). Waste transfers between states and watershed basins (Chesapeake Bay, Delaware Bay, Ohio River, the Great Lakes, and the New York Bay) were examined as well.
Their study revealed that for the 2011 year, industry reused or recycled 71.6% of the generated flowback and brine water, the majority of it being managed in-state. Drilling fluids were also mainly managed in-state, with 70.7% through reuse and 19.8% through brine or industrial waste treatment facilities. About half of the drill cuttings (50.4%) were disposed of in the Commonwealth, mainly in landfills. Approximately 20.0% and 28.5% were disposed of in Ohio and New York respectively, mainly in landfills. While industry reuse of flowback alone is high (89.8%), brine water reuse with its higher salinity and other constituents was found to be about 55%. Interstate transfer of brine water was 28.2% for 2011, mainly to underground injection wells. In 2011, disposal of wastes in PA waste treatment facilities that couldn’t meet Chapter 95 of the PA Code was discouraged. The findings indicate that brine water disposal practices at 2011 levels need to be revisited to evaluate future waste generation and disposal capacity.
For an in-depth review of the research, the article can be found in the Environmental Practice December 2012 issue.