Local participation in environmental decision making is a fundamental tenet of environmental justice. This essay examines the participation process for nuclear waste siting decisions and suggests that the lack of a viable means for discussion of competing values is a flaw in the currently used model of participation. Through analysis of the Yucca Mountain high-level nuclear waste site in the USA, I show how the lack of discussion of values occludes participation by marginalized American Indians. In particular, I examine the incommensurability between American Indian nations that value Yucca Mountain as sacred land and the federal government that values Yucca Mountain as a national sacrifice zone. I argue that Yucca Mountain acts as a polysemous value term in the controversy. My findings suggest that an environmentally just model of participation in environmental decision making must include a way to account for incommensurable values and cultural differences. Further, I highlight the lessons we can learn from the Yucca Mountain project as we deliberate about what to do with nuclear waste.