The emergence of hydraulic fracturing, or ‘fracking’, in the United States has generated a great deal of controversy and debate in recent years. I conduct a case study of the rulemaking process of Senate Bill 19-181 in Colorado in 2019-2020, which involves a devolution of power from the state to local level, as well as increased regulations on the oil and gas industry. This study addresses a gap in environmental governance and energy geographies literature by examining discourse dynamics in hydraulic fracturing-related rulemakings. Through a systematic analysis of public comments regarding SB 19-181, this study identifies distinct discourse coalitions within fracking debates, as well as key storylines, sources of evidence, and causal stories that are leveraged by stakeholder coalitions to influence rulemakings. This research explores the ways by which fracking debates are framed by stakeholders, the evidence sources of those arguments, and the ways by which stakeholders assert power using these arguments in pursuit of policy goals.