An Evaluation of the Toxicity of Hydraulic Fracturing Injectants∗

In the past 10–15 years, innovations in hydraulic fracturing and horizontal drilling have fueled a boom in the production of natural gas from geological formations that were previously unprofitable. The rapid deployment of fracking has been accompanied by concerns about negative externalities. In response, a regulatory regime has emerged that requires disclosure of chemical additives, but preserves a loophole by which firms can claim that such disclosure imperils “trade secrets.” To shed light on the importance of such a disclosure rule, we combine data from wells drilled in two significant gas fields in Wyoming with disclosure data from FracFocus about injected chemicals and materials. We explore the relation between toxicity of injectants, tendency to use the trade secrets shield, and identity of the well operator and the service company that performed the frac job. Our results have implications for the impact on social net benefits of the recently reported merger between two major service companies. JEL Codes: L71, Q35, Q53