An expanding array of transnational Environmental, Social, and Governance (ESG) standards has emerged to mitigate harms across critical minerals supply chains. This proliferation of international, private governance standards is interacting with domestic, public regulations guiding mining activity in resource rich states. When private and public requirements duplicate, overlap, or diverge they can create inconsistent processes, administrative burden, and dilemmas through a patchwork of basic components in supply chain management (Cashore et al., 2021). Applying a typology of interactions between private authority and public policy to lithium mining in Argentina, we argue that private/public rules are loosely complementary in some respects and independently coexisting in others. Comparing a rigorous private standard, the Initiative for Responsible Mining Assurance (IRMA), to public regulations we find that both include similar provisions for environmental protection and public participation . IRMA provides better protections for indigenous peoples’ participation, though it lacks significant enforcement mechanisms. Questions remain over the private sector's ability to guarantee – in practice – the rights of indigenous and other affected communities, or to protect ecosystems in the rush for critical minerals. Resulting governance dilemmas illustrate an increasingly crowded regulatory space in lithium mining that indiscriminately presumes public regulatory gaps, while it privatizes accountability.