This study examines the efforts of individuals and advocacy groups seeking to influence a state utilities commission's decisions regarding a large corporate merger and a nuclear power construction project. Such local engagements have wider significance as the nuclear industry attempts to expand its role in the global energy economy. Utilizing participatory field work and analysis of public documents, we extend the concept of rhetorical boundary work by examining two challenges faced by opponents of the merger and the nuclear project. First, the utilities commission's regulatory mandate is limited to economic risks rather than environmental, health, and safety risks. Second, expert authority is consistently privileged over local, vernacular arguments. We explore the rhetorical negotiation of these boundaries and the effects produced.