The need for greater citizen participation in EIA is well established, as are the numerous barriers to such participation. Yet there are still important gaps in understanding what political-economic power relations undermine participation. In particular, there are few studies linking (neo)colonialism, neoliberalism and austerity to EIA governance and citizen participation. Moreover, there are comparatively fewer studies of EIA from Latin America, and even less from the Caribbean. In this paper, we contribute to filling these two gaps by studying the connections between structural forms of power of colonial-neoliberal governance, and the experiences of EIA participation in the Caribbean island-nation of Puerto Rico. Despite having been a pioneer in EIA implementation, there are no English-language studies focused on Puerto Rico's EIA process. We find strong limitations to citizen participation in EIA, including lack of access to information, pro-forma participation for previously-made decisions, favoring of private economic interests over sustainability and justice, and a legal framework restricting participation and environmental protection. We argue that these limitations are produced through the colonial neoliberal transformations of environmental governance in Puerto Rico, in particular: policies of extreme deregulation and austerity, a permanent state of emergency and exception, and a highly corrupt corporatocracy.