Scientific arguments-or appeals to the authority of science and/or use of scientific and technical knowledge as evidence in arguments-play an important role in the deliberation of public controversies. This is evident across the many examples of environmental policy discussed in the rhetoric of science literature (e.g., Farrell & Goodnight, 1981; Fisher, 1987; Gross, 1984; Katz & Miller, 1996; Keränen, 2005; Lyne & Howe, 1986; Waddell, 1990). One area of particular interest in this body of literature is the research that has shown that scientific and technical knowledge is often valued over social, political, or pathos-based arguments in public deliberations, which results in a marginalization of these other ways of knowing (e.g., Fisher, 1987; Gross, 1984; Waddell, 1990), and in the preceding chapters of this book. This is notable because controversies over intelligent design, human genomics, and nuclear power often involve politically charged clashes that pit the authority of scientific knowledge against the authority of cultural knowledge, cultural beliefs, and religion and spirituality (see Chapters 1 and 2 in this volume). It is in this vein that this chapter examines the controversy surrounding plans to install a high-level nuclear waste site in the Yucca Mountains in Nevada (U.S. Department of Energy, 2008b). Although the details of this site will be discussed later in the chapter, it needs to be noted here that in this particular controversy, the Department of Energy (DOE) specified the scientific and technical suitability of the Yucca Mountain site as its only criterion in considering whether or not to proceed, as evidenced in a mandate in the Nuclear Waste Policy Act (NWPA) (Nuclear Waste Policy Act, 2004). As will be argued in this chapter, this specification artificially limited the scope of a controversy that essentially bridges the public and technical spheres of argument (Goodnight, 1982) and invokes ethical, spiritual, political, cultural, and scientific arguments. During the public hearing process, public participants-specifically American Indians-appealed to the authority of science as well as the authority of their own cultural knowledge, including the narrative-based knowledge of oral traditions and religious beliefs.