Probabilistic modeling of shale gas containment pits for environmental and safety management

The Marcellus Shale formation contains large natural gas reserves, which are increasingly being extracted using horizontal drilling techniques. Concerns about environmental effects have prompted studies regarding Marcellus operations, including the safety of pits and impoundments containing frac fluids and freshwater. A subset of these structures in West Virginia was evaluated using a risk-based field data collection tool, which revealed recurring problems. A probability-based method was developed to determine the likelihood of these problems occurring in larger sample sizes. Applying this method to portfolios of pits and impoundments would benefit the industry by identifying areas of improvement for construction and inspection.