This thesis is about the controversies that engulfed TransCanada's Energy East pipeline project from the moment it emerged into the public sphere in 2013, and which led to its ultimate demise in 2017. As such, it is an investigation into how power, sovereignty, and agency were mobilized in the negotiation of a pipeline project in Canada. In the contemporary political and environmental climate, pipeline projects have had a rough go of it. Sweeping changes made to the legislative and regulatory framework by the Conservative federal government in 2012 were intended to expedite their approval but appear to have had a contrary effect. Rather than provide certainty to proponents, the changes further undermined the decisional infrastructure and distribution of constitutional authority. In this context, the contest has been less about substantive deliberation than infrastructural determination, as normative decisional frameworks became further unsettled. The controversy opened up a wide range of questions, such as: Who had power to decide? Which jurisdictions applied? How should democratic participation be delineated? Who was the public that the regulator purportedly spoke for? How were decisions justified? What counted as evidence? In other words, it was as much about which projects might be considered as being in the "national" interest as it was about the procedural and epistemological channels through which this determination should be made. My observation has been that stuck between growth imperatives, vested interests, democratic expectations, and a growing recognition of impending environmental crisis, governments and companies like TransCanada prefer determinate power relations: a clear and exclusive allocation of decision-making authority. They also prefer indeterminate substantive guidelines, writing as much discretionary power into the law as possible and leaving open the possibility of strict environmental protections in general while allowing for exceptions in the specific. Environmental assessment reformists, on the other hand, prefer indeterminate power — a shared and inclusive distribution of decision-making power — and determinate substantive legal guidelines. What substantive indeterminacy combined with centralized, exclusive power makes possible is framing contingent transgressions of overall political goals as exceptional. In the controversy over TransCanada’s pipeline project, the public was not just pushing back against oil and its potentially devastating effects. They were also pushing back against a regulatory infrastructure which evacuated too much of its political agency and normalized the particular interests of some as the inevitable future for all.