<p>A multimodal, critical approach to Discourse allows us to understand contemporary environmental debates in a nuanced way. Fossil fuel mining has become especially controversial due to the environmental, health, and social impacts, as well as the substantial economic dependence on such development. Wider discussions surrounding mining projects tend to diverge into two major oppositions: that of the industry itself, and that of local activists protesting development on their lands. Research in these areas has leaned towards a focus on the use of environmental language by polluting industries, termed ‘greenwash’, missing to some degree the ways in which these and other Discourses are articulated multimodally through interaction. This thesis brings a critical, multimodal analysis to controversial mining debates which go ‘beyond greenwash’, in order to track how Discourses are appropriated, resisted, and re-entextualised. In this thesis I adopt overlapping critical, multimodal, and ethnographic theoretical lenses to view interaction surrounding two controversial mining case studies: the Athabasca tar sands in Alberta, Canada and a lignite coal mine expansion in Southland, Aotearoa/New Zealand. Drawing upon an understanding of human communication as inherently multimodal, I include video-recorded interviews with both activists and industry representatives, as well as relevant artefacts (such as pamphlets, photographs, signs, etc) in my dataset. Using mediated action as the unit of analysis, I employ Multimodal Interaction Analysis to examine interview interaction, coupled with methods from Social Semiotics to interrogate designed artefacts. These analytical frameworks, viewed through combined theoretical lenses, provide a unique perspective on the way Discourses are appropriated and creatively resisted in debates about resource development. In both case studies, Discourses of the environment and the economy are appropriated by activists and industry actors, forming the basic ‘Environment v. Economy’ Discourse. This dichotomy is expanded through the appropriation of additional Discourses, such as regional identity in both Southland and Alberta. Activist groups subsequently resist and re-appropriate these regional Discourses by multimodally re-contextualising them. In Alberta, additional Discourses of Indigenous and LGBTQ+ identities are appropriated by industry actors in attempts to legitimise mining expansion. While some of these appropriations draw upon ideas of intersecting oppressions, mining industries fail to adequately address the ways in which resource extraction contributes to those oppressions. However, these actions are both recognised and resisted by local anti-tar sands activists, who use public events and designed artefacts to display their opposition and reappropriate Discourses. Although both case studies are concerned with similar types of fossil fuel extraction, there are notable differences. Whereas Discourses of the environment, the economy, and regional identity are both appropriated and resisted in Southland and Alberta, it appears that in Alberta, industry actors draw upon a wider variety of Discourses. This may be due, in part, to the fact that the Athabasca tar sands controversy has had a longer development period and more international resistance, meaning there is more pressure to legitimise new and ongoing projects. This has led to a type of ‘discursive arms race’, where wider Discourses are appropriated as other, more directly-linked, Discourses are exhausted (e.g. the environment). In response, activists in both Southland and Alberta make use of creativity and humour in mundane performances to enact satirical representations of powerful industry actors. While these performances occur regularly in many of my interviews, activists in Alberta also tend to stage elaborate and humorous theatrics in order to criticise government and industry approaches to fossil fuel development. The unique framework employed in this thesis has resulted in a number of research implications. These include the combination of Critical Discourse Analysis with a multimodal, ethnographic approach, and the coupling of Multimodal Interaction Analysis with Social Semiotics to expand my analytical reach. Additionally, I have made use of a variety of modes in this thesis’ presentation, in order to exploit each mode’s affordances and better represent the complexity of my dataset. Finally, from a critical perspective, this research offers an agenda of empowerment for environmental justice activist groups struggling to protect their lands.</p>