This thesis details a muonic investigation of the Canadian used fuel container design for long-term nuclear waste storage in a deep geological repository. The carbon steel container is Cu-coated by cold-spray and electrodeposition and forms a surface oxide in air. These layers guard against hazardous environmental species; protons sourced from aqueous or acidic ground conditions may diffuse into the container, combining with electrons to form atomic hydrogen, generating H2/H- and enabling hydrogen/hydride blistering, posing damage to the container. Muons are used as surrogate protons for atomic-level observations of proton dynamics and reactions, exploring environmental impacts on the container and on proton interactions within each layer, identifying conditions conducive to blistering and characterizing proton reaction pathways that evolve as materials undergo anticipated corrosion under radiolytic humid-air conditions. Atomic hydrogen is inferred to preferentially form near the Cu surface and within the surface oxide layer, pre- and post-corrosion by nitric acid.