Internalizing Externalities: Disclosure Regulation for Hydraulic Fracturing, Drilling Activity and Water Quality

The rise of shale gas and tight oil development has triggered a major debate about hydraulic fracturing (HF). In an effort to mitigate risks from HF in unconventional development, many U.S. states have introduced disclosure mandates for HF fluids. In this paper, we study the effects of this important regulatory initiative on HF activity and its environmental impact. We find significant improvements in water quality, examining salts that are considered signatures for HF impact, after the disclosure mandates are introduced. We document effects along the extensive margin (less HF activity) and the intensive margin (less per-HF well impact). Most of the improvement comes from the intensive margin. Supporting this interpretation, we find that, after the introduction of disclosure, operators pollute less per unit of production, use fewer toxic chemicals, and that there are fewer spills related to the handling of HF fluids and wastewater. We also explore possible mechanisms through which disclosure regulation can be effective and find that public pressure likely plays an important role. Taken together, our empirical assessment of a major regulatory initiative for HF provides novel evidence on how disclosure mandates can help to internalize negative and fairly widespread external effects.