Recycled text and risk communication in natural gas pipeline environmental impact assessments

Under the U.S. National Environmental Policy Act (NEPA), energy infrastructure projects that are permitted by federal agencies require preparation and publication of an environmental impact assessment. However, fifty years after the passage of NEPA, agencies’ compliance behaviors, and how these behaviors might shape the risks associated with energy infrastructure, remain largely unexplored. Here, we consider how assessment documents from forty-six of the largest U.S. natural gas pipeline mega-projects address landslide risks. Using a series of text mining and content analysis methods, we evaluate the prevalence of recycled text across assessments. We find that text similarity does not correspond closely to reported risk levels – in many cases, common verbiage is used and only project-specific details (e.g., locations, numeric figures) are substituted. While such approaches likely expedite preparation of assessments and facilitate knowledge transfer between projects, we argue that common text potentially hinders clear communication of differential risks to decision-makers and the public, who may lack the technical expertise to contextualize the magnitude and severity of reported figures. In light of ongoing policy efforts to streamline lengthy and costly energy infrastructure permitting processes under NEPA, it is vital that such efforts do not undermine the risk communication requirements of the review process.